ILLINOIS POLLUTION CONTROL BOARD
April 17, 1997
IN THE MATTER OF:
TIERED APPROACH TO CORRECTIVE
ACTION OBJECTIVES (TACO): 35 ILL.
ADM. CODE PART 742
)
)
)
)
)
R97-12 (A)
(Rulemaking - Land)
Proposed Rule.
Second Notice.
OPINION AND ORDER OF THE BOARD (by M. McFawn and J. Yi):
On September 16, 1996 the Illinois Environmental Protection Agency (Agency) filed a
proposal to add a new Part 742 to the Board’s rules, which would create a tiered approach to
establishing corrective action objectives (also known as TACO). The Board accepted this
matter for hearing on September 19, 1996. On November 7, 1996, the Board sent this matter
to First Notice without commenting on the merits of the proposal. By today’s action, the
Board sends the proposal to Second Notice, pursuant to the Administrative Procedure Act (5
ILCS 100/1-1
et seq.
(1994)), for consideration by the Joint Committee on Administrative
Rules.
The proposed rules create a tiered approach to establishing corrective action,
i.e
.
remediation objectives, based on risks to human health and the environment, allowing
consideration of the proposed land use at a subject site. Although this approach is premised
upon the statutory mandates in the Site Remediation Program legislation (P.A. 89-431, as
amended by P.A. 89-443), it is intended to apply to all types of remediation programs under
the Act, including not only the Site Remediation Program, but also the Underground Storage
Tank and the Resource Conservation and Recovery Act programs.
PROCEDURAL HISTORY
The proposed rules are required by P.A. 89-431, which was signed and became
effective December 15, 1995, as amended by P.A. 89-443, effective July 1, 1996. P.A. 89-
431, as amended by P.A. 89-443, added Title XVII to the Environmental Protection Act
(Act)(415 ILCS 5/1
et seq.
(1994)), also known as the Site Remediation or Brownfield
legislation. Title XVII is intended to achieve five objectives. Those objectives are to: 1)
establish a risk-based system of remediation based on the protection of human health and the
environment relative to present and future use of the land; 2) assure that the land use for which
remedial action was undertaken will not be modified without consideration of the adequacy of
such remedial action for the new land use; 3) provide incentives for the private sector to
undertake remedial action; 4) establish expeditious alternatives for the review of site
investigation and remedial activities, including a privatized review process; and 5) assure that
2
the resources of the Hazardous Waste Fund are used in a manner that is protective of human
health and the environment relative to present and future uses of the site and surrounding area.
The proposed TACO rules are intended to achieve the first two of these objectives.
As noted by the Board in its September 19, 1996 order, the Agency filed two additional
rulemaking petitions when it filed this rulemaking: a proposal for a new Part 740, In the
Matter of:
Site Remediation Program and Groundwater Quality
, establishing procedures for
the Site Remediation Program, docketed as R97-11; and In the matter of:
Leaking
Underground Storage Tanks
docketed as R97-10, a proposal to amend the regulations
governing underground storage tanks. Like the TACO rules in the instant docket, the Site
Remediation Program was mandated by P.A. 89-431, while the underground storage tank
amendments were mandated by P.A. 89-457, effective May 22, 1996. The TACO rules
provide the acceptable methodologies for determining site-specific, risk-based remediation
objectives. The programs to which TACO applies govern the scope and extent of the site
investigation preceding the application of TACO, as well as the no further remediation
determination made by the Agency after the TACO derived remediation objectives are
achieved.
Docket B
Today the Board also adopts a separate opinion and order creating a Docket B. The
Board finds it necessary to propose for First Notice new rules concerning a single issue. The
Agency has requested that the Board adopt a “mixture” rule,
i.e.
, a rule which requires that an
applicant consider the cumulative effect of similar-acting contaminants at a site when
developing the appropriate remediation objectives. For the most part, the Agency’s request
was developed in a series of filings subsequent to the public hearings in this matter, and with
minimum justification in support of such rules. Initially, the Agency only requested a mixture
rule under Tier 2 for noncarcinogenic chemicals. In its later filings, the Agency requests that
the Board also adopt a mixture rule applicable to the development of groundwater remediation
objectives under Tier 1 for both carcinogenic and noncarcinogenic chemicals, and further
requests that the Tier 2 rule be applicable to carcinogenic chemicals in groundwater. There is
insufficient information in the record for the Board to adopt in its entirey the mixture rule
ultimately requested by the Agency. The justification provided in support of expanding the
rule’s applicability however does indicate that absent such a rule, remediation objectives
determined using TACO may not be protective of human health at sites with multiple, similar-
acting chemicals. Therefore, the Board finds it necessary to clearly examine the “mixture
rule” proposed by the Agency to determine to what extent it is necessary to insure that the
remediation objectives developed under TACO are protective of human health in all
circumstances. Docket B is opened for that purpose.
The Board has a statutory deadline of June 16, 1997 to finalize the TACO proposal
presented by the Agency on September 16, 1996. Because this issue was introduced so late in
this rulemaking process, it cannot be fully examined and resolved within that timeframe. In
order to meet the statutory deadline for adopting rules based upon the Agency’s proposal, the
Board finds it necessary to bifurcate this rulemaking. As expeditiously as possible, the Board
3
will hold hearings under the new Docket B and proceed to final adoption of a mixture rule, to
the extent such is demonstrated to be necessary.
Development of the Proposal
Section 58.11 of the Act, adopted as part of the Site Remediation Program legislation,
created the Site Remediation Advisory Committee (SRAC) to advise the Agency in developing
the mandated TACO and the Site Remediation Program regulatory proposals. The SRAC
consists of one member from each of the following organizations: the Illinois State Chamber of
Commerce, the Illinois Manufacturers Association, the Chemical Industry Council of Illinois,
the Consulting Engineers Council of Illinois, the Illinois Bankers Association, the Community
Bankers Association of Illinois, and the National Solid Waste Management Association. In
addition, representatives from the Illinois Petroleum Council, the Illinois Petroleum Marketers
Association, and the City of Chicago participated. The Agency met with the SRAC, or
subgroups thereof, ten times between March 14, 1996 and August 30, 1996, to discuss both
the instant proposal and the proposed rules for the Part 740 Site Remediation Program. The
Agency testified that, although minor differences may exist, consensus was reached on all
major issues. (See Exh. 1 at 11.)
The Agency filed its proposal for rulemaking on September 16, 1996, accompanied by
a motion for acceptance of proposal, the statement of reasons, and a motion regarding
incorporations by reference. On September 19, 1996, the Board accepted this matter for
hearing and granted the motion regarding incorporations by reference. Additionally, the Board
directed the Agency to file a completed copy of the economic impact form required by the
Joint Committee on Administrative Rules. The Agency submitted its economic impact form
on October 28, 1996. On November 7, 1996, the Board sent this matter to First Notice
without commenting on the merits of the proposal. Subsequently, on December 6, 1996 the
proposal was published in the
Illinois Register
(20 Ill. Reg. 15429).
Two sets of hearings were held in this matter during First Notice. The first set of
hearings, held on December 2 and 3, 1996, in Chicago, and on December 10, 1996 in
Springfield, was reserved for the Agency’s presentation of its proposal and questions for
Agency witnesses. The second set of hearings, held on January 15 and 16, 1997 in
Springfield, was for the purpose of addressing remaining questions for the Agency, allowing
the presentation of testimony by other interested participants, and allowing questions directed
to those testifying.
At the first hearing, the Agency presented the testimony of four witnesses: Mr. Gary
King, who provided an overview of the proposal, and testified concerning Subpart A
(Introduction), Subpart C (Exposure Route Evaluation), Subpart J (Institutional Controls) and
Subpart K (Engineered Barriers); Mr. John Sherrill, who testified concerning Subpart B
(General), Subpart E (Tier 1 Evaluation), Subpart F (Tier 2 General Evaluation), Subpart G
(Tier 2 Soil Evaluation), Subpart H (Tier 2 Groundwater Evaluation), Appendix A (General),
Appendix B (Tier 1 Tables and Illustrations), Appendix C (Tier 2 Tables and Illustrations),
and Appendix D (Procedures for Determination of Class II Groundwater); Dr. Thomas
4
Hornshaw, who testified concerning Subpart D (Determining Area Background), Subpart E
(Tier 1 Evaluation), Subpart F (Tier 2 General Evaluation), and Subpart H (Tier 2
Groundwater Evaluation); and Ms. Tracey Virgin, who testified concerning Subpart I (Tier 3
Evaluation). Additionally, the Agency had four additional personnel available throughout the
proceedings to respond to questions: Messrs. Ken Liss, Douglas Clay, Jim O’Brien, and
Lawrence Eastep.
At the second set of hearings, the following persons presented testimony concerning the
rulemaking proposal: 1) Mr. Harry Walton, on behalf of the Illinois State Chamber of
Commerce, the Illinois Manufacturers Association, and the Illinois Environmental Regulatory
Group; 2) Ms. Karen Lyons, on behalf of the Illinois Petroleum Council; 3) Mr. John Watson
and Ms. Linda Huff, on behalf of Gardner Carton & Douglas, and a coalition of clients
including B.F. Goodrich Company, Commonwealth Company, Hydrosol Inc., INX
International Ink Company, Northern Illinois Gas Company, William Wrigley Jr. Company,
and Woodward Governor Company (the Site Remediation Coalition); 4) Mr. Ray Reott, on
behalf of Jenner & Block; and 5) Mr. David Rieser, on behalf of the Illinois Steel Group.
The following exhibits were submitted at hearing:
Exhibit No.
Exhibit Name
1.
Pre-filed Testimony of Gary King re: Legislation and Regulatory Development,
submitted December 2, 1996.
2.
Pre-filed Testimony of Gary King re: Subparts A and C, submitted December 2, 1996.
3.
Pre-filed Testimony of Gary King re: Subparts J and K, submitted December 2, 1996.
4.
Pre-filed Testimony of John Sherrill re: Subparts B, E, F, G, and H, and Appendices
A, B, C, and D with Attachments A through H , submitted December 2, 1996.
5.
Pre-filed Testimony of Dr. Thomas Hornshaw re: Subparts D, E, F, and H, with
Attachments A through D, submitted December 2, 1996.
6.
Pre-filed Testimony of Tracey Virgin re: Subpart I, submitted December 2, 1996.
7.
Agency Errata Sheet No. 1, submitted December 2, 1996.
8.
Agency’s Revised 742.Appendix A though Appendix D, submitted December 2, 1996.
9.
Agency Table: Comparison of Physical/Chemical Constants Used in ASTM’s Risk
Based Corrective Action Example Look-up Table (Table X2.1) and Part 742 Tier I
Tables (Appendix B, Tables A and B).
10.
Agency 3-page Handout: 742.600(e) - (g) Tier 2 Examples 1 - 3.
5
11.
Agency Errata Sheet No. 2.
12.
Pre-filed Testimony of Harry Walton.
13.
Pre-filed Testimony of Karen Lyons, with Attachments A, B, and C.
14.
Pre-filed Testimony of John Watson, with Attachments A and B.
15.
Pre-filed Testimony of Linda L. Huff, with Attachments A and B.
16.
Group Exhibit 16, Attachments C, D, E, F, and G to Pre-filed Testimony of Linda
Huff.
17.
Group Exhibit 17 from Pre-filed Testimony of Linda Huff - Documents from other
states’ programs: Michigan (Documents A and D), Massachusetts (Document B), and
Indiana (Document C).
18.
Pre-filed Testimony of Ray Reott of Jenner & Block.
19.
Group Exhibit 19, Attachments A, B, and C to Pre-filed Testimony of Ray Reott of
Jenner & Block.
20.
Agency’s Rebuttal Testimony.
21.
Agency’s Second Revised Appendices A, B, C, and D.
In addition to the testimony presented at hearing and the exhibits submitted at hearing,
the following public comments were submitted into the record:
PC No.
Public Comment
Date
1.
Comment of Robert L. Johnson, P.E.
1/2/97
2.
Technical Assistance Document for complying with the TC rule
and Implementing the Toxicity Characteristic Leaching Procedure
(TCLP), submitted by Ray Reott of Jenner & Block.
1/24/97
3.
Letter to Doug Clay, Bureau of Land, Illinois Environmental Protection
Agency.
1/27/97
4.
Post-Hearing comments of the Illinois Environmental Regulatory Group,
submitted by Whitney Wagner Rosen.
2/20/97
5.
Post-Hearing comments of the Site Remediation Advisory Committee,
submitted by Whitney Wagner Rosen.
2/20/97
6
6.
Post-Hearing Comments submitted by Scott R. Green, C.P.G. Chicago,
Illinois.
2/20/97
7.
Post-Hearing Comments of the Illinois Steel Group, submitted by David
L. Rieser.
2/20/97
8.
Post-Hearing Comments of the Illinois Petroleum Council, submitted by
David L. Rieser.
2/20/97
9.
Final Comments of Gardner Carton & Douglas, submitted by Lewis
Putman.
2/21/97
10.
Final Comments of the Illinois Environmental Protection Agency,
including final errata changes.
2/24/97
11.
Comments of Mayer, Brown & Platt, submitted by Patricia F. Sharkey.
2/24/97
12.
Pre-filed testimony of Roy O. Ball on behalf of the Illinois Steel
Group.
1
12/24/96
13.
Comments of the City of Chicago submitted by Henry L. Henderson,
Commissioner.
3/13/97
14.
Comment from SEECO Environmental Services, Inc. submitted by
Collin w. Gray, S.E., P.E., President.
3/13/97
15.
Additional Comments of the Illinois Environmental Protection Agency
submitted by Kimberly A. Robinson.
3/13/97
16.
Statement of the Site Remediation Advisory Committee submitted by
Whitney Wagner Rosen.
3/13/97
17.
Comment of the Illinois Environmental Protection Agency submitted by
Kimberly A. Robinson as a Motion to File Instanter Additional Language
2/13/97
1
Roy O. Ball’s comments were originally, submitted as pre-filed testimony; however Mr. Ball
was unavailable for hearing, and his pre-filed testimony was admitted into the record as a
public comment.
7
18.
Post-Hearing Comments of Jenner & Block submitted by Raymond
Reott.
3/13/97
19
Public Comment submitted by Jeffery L. Pope, P.E., Director,
Environmental Management and Remediation, Clayton Environmental
Consultants.
3/13/97
20.
Additional Comments of the Illinois Petroleum Council submitted by
David L. Rieser.
3/13/97
21.
Site Remediation Advisory Committee’s Motion to File Instanter;
Additional Comments of the Site Remediation Advisory Committee.
3/27/97
22.
Follow-Up Comments of the Illinois Environmental Protection Agency
submitted by Kimberly A. Robinson.
3/27/97
OVERVIEW OF THE TACO PROCESS
The proposed rules establish procedures for developing remediation objectives for soil and
groundwater at remediation sites based on risks to human health, taking into account the existing
pathways for human exposure and current and future use of the remediation site. The proposed
methodology consists of a three tiered approach for establishing remediation objectives. The tiers
can operate fully independent of each other, and it is not necessary to perform a Tier 1 analysis
before performing a Tier 2 or Tier 3 analysis, or to perform a Tier 2 analysis before performing a
Tier 3 analysis. Each successive tier allows the person conducting a remedial investigation pursuant
to the Act (hereinafter referred to as the “applicant”) to rely on more site-specific information, and
requires a concomitant increase in the level of site-specific investigation and analysis under Part
742.
As a prerequisite to using the tiered approach to establish remediation objectives, the
applicant must determine the contaminants of concern at the site. This is done by conducting a site
investigation under the applicable remediation program; such investigation is not part of the TACO
process. Again, the programs with which TACO is to be used include the Leaking Underground
Storage Tank program at Parts 731 and 732, the Site Remediation Program proposed at Part 740,
and the RCRA Part B Permits and Closure Plans at Parts 724 and 725. As mentioned at the outset,
these programs govern the activities at the site which address the contamination, including the scope
of the site investigation and ultimately the no further remediation determination made by the
Agency. (Hereinafter in the opinion, these programs are referred to as the “governing programs.”)
The specific requirements of the governing program control how TACO is applied to determine the
applicable remediation objective.
After identifying the contaminants of concern, the applicant can use the TACO process to
establish remediation objectives. Each tier of the TACO process requires the applicant to consider
up to four potential exposure routes for each contaminant of concern: 1) the inhalation exposure
8
route; 2) the soil ingestion route; 3) the dermal contact exposure route;
2
and 4) the groundwater
ingestion route. The groundwater ingestion route is further subdivided into two components: 1) the
migration to groundwater, or soil component which must be investigated to establish a soil
remediation objective; and 2) the direct ingestion of groundwater, or groundwater component,
which must be investigated to establish a groundwater remediation objective. (Hereinafter each
component of the groundwater ingestion route is referred to as the “soil component” or the
“groundwater component”). Alternatively, as described in greater detail below, the applicant can:
1) demonstrate that a particular exposure route is not available for a contaminant of concern, and
thereby exclude further consideration of that exposure route for that contaminant, or 2) rely on area
background concentrations in establishing remediation objectives or to demonstrate that further
remediation is not warranted.
A Tier 1 analysis requires the applicant to compare levels of contaminants of concern at the
remediation site to pre-determined remediation objectives. The pre-determined remediation
objectives are listed in the rules at Appendix B, Tables A through E. Separate remediation
objectives are established for properties designated for residential use and for industrial/commercial
use. The residential levels are the most stringent and are considered protective for all uses. The
industrial/commercial levels are less stringent and must be accompanied by an institutional control,
such as a deed restriction, in order to assure that the site is used only for industrial/commercial
purposes. Additionally, if the site is to be remediated to industrial/commercial levels, the applicant
must assure that the remediation levels established for construction workers are also achieved. If
any contaminants of concern at a remediation site are found to exceed the applicable pre-determined
levels, the applicant is required to remediate the contamination until the remediation objectives are
achieved, or alternatively, to develop site-specific remediation objectives using a Tier 2 or Tier 3
analysis. Under Tier 1, if multiple noncarcinogenic chemicals with similar-acting properties are
present in the groundwater, their cumulative effect must be evaluated as part of the development of
remediation objectives.
A Tier 2 analysis uses equations set forth in the proposed rules to develop alternative
remediation objectives for contaminants of concern using site-specific information. The equations
used to develop site-specific remediation objectives are from the United States Environmental
Protection Agency’s (USEPA) Soil Screening Levels Guidance (SSL) and the American Society of
Testing and Material’s (ASTM) Risk Based Corrective Action (RBCA). The equations are set forth
in the proposed rules at Appendix C, Tables A and C, respectively. If any contaminants of concern
are found to exceed the remediation objectives developed using the Tier 2 equations, the applicant
is required to remediate the contamination until the objectives are achieved or to develop alternative
objectives using a Tier 3 analysis. The mixture rule for noncarcinogens is also applicable under
Tier 2. Unlike a Tier 1 analysis, however, it is applicable when developing both soil and
groundwater remediation objectives.
A Tier 3 analysis allows the applicant to develop remediation objectives using alternative
parameters not found in Tier 1 or Tier 2. It allows the applicant great flexibility in developing
2
The dermal contact exposure route need only be considered if the applicant elects to use the
Tier 2 Risk Based Corrective Action (RBCA) equations set forth in Appendix C, Table C, or a
Tier 3 formal risk assessment, to establish remediation objectives.
9
remediation objectives appropriate for a particular site based upon site-specific information rather
than relying on general categories of information. The options available under Tier 3 include: use
of modified parameters in the Tier 2 equations; use of alternative models; conducting a site-specific
risk assessment; assessment of impractical remediation; and variation of the target risk level. If any
contaminants of concern are found to exceed the remediation objectives developed using the Tier 3
analysis, the applicant is required to remediate the contamination until the objectives are achieved.
At this time, the mixture rule is not specifically applicable to a Tier 3 analysis.
Outside of the individual tiers of analysis, there are two alternative means for addressing the
presence of contamination: exclusion of pathways and reliance on area background. The first
option, exclusion of pathways, is based on the premise that an exposure pathway must exist for
contamination to present a threat to human health. If it can be shown that a pathway does not exist
for any contaminants of concern, the applicant need not address that exposure pathway for those
contaminants. The methods for evaluating and excluding exposure routes are set forth at Subpart
C. The second option, reliance on area background, is based on Section 58.5(b)(1) of the Act,
which provides that applicants shall not be required to remediate contaminants of concern to levels
that are less than area background levels. If it can be shown that a contaminant of concern is
present at levels that do not exceed area background levels for the site, the applicant need not
further address that contaminant. Under appropriate circumstances, the applicant can also use
background levels as remediation objectives. The methods for determining area background
concentrations are set forth in Subpart D.
The applicant can use any combination of tiers if multiple contaminants of concern are
present at a site. Remediation objectives established under any tier are considered equally health
protective for a particular land use. Upon completion of remedial activities which achieve the
established remediation objectives, the applicant is entitled to a no further remediation
determination in accordance with the terms of the governing program. The TACO rules themselves
do not provide for the no further remediation determination; they provide only the process for
determining site-specific remediation objectives based upon risk. The no further remediation
determination is made at the conclusion of the process by the Agency pursuant to the governing
program. For example, the Agency’s no further remediation determination in the Site Remediation
Program is effected through a No Further Remediation Letter. The same instrument is used in the
Underground Storage Tank Program.
The following section contains a more detailed summary of the components of the rules. A
third section of the opinion beginning at page 33 contains a detailed summary of the major issues
raised concerning various components of the TACO rules.
SUMMARY OF THE SECOND NOTICE PROPOSAL
Subpart A: Introduction
This subpart contains sections concerning intent and purpose, applicability, overview and
key elements of the tiered approach, and the requirements for site characterization. Section
742.100, entitled “Intent and Purpose,” states that Part 742, the TACO process, is intended to
establish procedures for use in evaluating risks to human health posed by environmental conditions,
and procedures for use in developing objectives for remediation which assure that risks are at
10
acceptable levels. Furthermore, Section 742.100(b) states that the procedures are intended to
provide adequate protection of human health and the environment based on risks to human health
posed by environmental conditions while incorporating site-related information.
Section 742.105 sets forth the situations in which the rules are intended to apply. The
applicant may use the Part 742 procedures to the extent allowed by state and federal law. The
procedures must be used in accordance with the requirements of the program pursuant to which the
remediation is being conducted. Section 742.105 specifically references the Leaking Underground
Storage Tank program, the proposed Site Remediation Program, and the RCRA Part B Permits and
Closure Plans. The use of Part 742 is subject to the limitation that it cannot be used where there is
an imminent and substantial endangerment to human health and the environment. Section 742.105
also makes clear that groundwater remediation objectives established pursuant to the TACO process
can exceed the groundwater quality standards set forth at 35 Ill. Adm. Code Part 620. This
exception is based upon a statutory provision; the record does not otherwise support such a rule.
Section 58.5 of the Act authorizes the use of groundwater remediation objectives for contaminants
of concern that are greater than the groundwater quality standards established by the Board at 35 Ill.
Adm. Code 620 pursuant to the Illinois Groundwater Protection Act. (415 ILCS 55/1
et seq
.) The
Board has made clarifying changes to Section 742.105 to notify the applicant that remediation
objectives greater than the Part 620 standards may be developed only under Tier 3.
The Agency also proposed a rule to the effect that a no further remediation determination
constitutes
prima facie
evidence that the contaminants of concern addressed at a site do not cause or
tend to cause water pollution pursuant to Section 12(a) of the Act, or create a water pollution
hazard pursuant to Section 12(d) of the Act. Such a statement would be particularly critical at sites
remediated to groundwater objectives greater than the State’s groundwater quality standards because
those groundwater quality standards were adopted as being the minimum levels protective of human
health and the environment pursuant to the Illinois Groundwater Protection Act. (Id.) As
explained above, Section 58.5 of the Act allows an applicant to propose and the Agency to approve
pursuant to Tier 3 of TACO, remediation objectives greater than the State’s groundwater quality
standards. Therefore, once such a remediation objective is achieved, the Agency’s no further
remediation determination in effect deems the levels of contamination remaining at the site as
protective of human health. Yet, the programs used in conjunction with TACO govern the scope
and extent of the legal protection provided by a No Further Remediation Letter or any other type of
no further remediation determination made by the Agency. Therefore, the Board will not adopt
under TACO the rule proposed by the Agency addressing the effect of a no further remediation
determination.
Section 742.110 contains an overview of the tiered approach, which is similar to the
summary of the rules set forth above. We will not repeat that discussion here. The applicant is
well advised to consult the illustrations in the Appendices when trying to understand the TACO
process generally, and any particular provisions. The illustrations provide road maps and “decision
trees” which work well to explain the TACO process. Generally, Illustrations A and B of
Appendix A provide decision trees for developing soil and groundwater remediation objectives,
respectively. Illustration A of Appendix B provides such a road map for Tier 1, and Illustrations A
and B of Appendix C provides the same for Tier 2. However, none of the illustrations include the
effect of the mixture rule adopted today.
11
Moreover, Section 742.115 addresses the “Key Elements of the Tiered Approach.” It sets
forth the exposure routes that must be evaluated, the factors that must be considered in determining
the remediation objectives for contaminants of concern, and the potential land use classifications for
the site. Section 742.115(a) sets forth the potential exposure routes that must be addressed at a
remediation site, specifically: inhalation, soil ingestion, groundwater ingestion, and dermal contact
with soil. The groundwater ingestion route is further divided into two components: the soil
component and the groundwater component. The dermal contact exposure route need only be
addressed if the applicant develops remediation objectives using RBCA equations set forth in
Appendix C, Table C, or through a formal risk assessment under Tier 3. For each contaminant of
concern, the applicant must develop remediation objectives for each applicable exposure pathway or
demonstrate that a pathway has been excluded from consideration.
Section 742.115(b) sets forth the factors that must be considered when identifying the
contaminants of concern at the remediation site. These factors include: 1) the materials and wastes
managed at the site; 2) the extent of the no further remediation determination which the applicant is
seeking from the Agency under the governing program,
e.g
., under the Site Remediation Program,
a comprehensive or focused No Further Remediation Letter; and 3) the general requirements
applicable under the governing program. In the Site Remediation Program or a Section 4(y)
voluntary cleanup, the applicant determines the scope of the remediation and the contaminants of
concern that will be addressed. In other programs, the scope of the remediation and contaminants
of concern will be dictated by the governing program’s requirements. At the conclusion of the
process, the Agency will make a determination about whether further remediation is necessary
under the governing program. If the Agency determines that no further remediation is necessary,
the scope of the determination will extend only to the scope of the remediation performed.
Section 742.115(c) sets forth the possible land use classifications under the TACO process.
The rules allow the proposed land use to be characterized as one of the following: residential,
conservation, agricultural, or industrial/commercial. The land use classification determines the
expected exposure scenario at the site, which is a principal factor in establishing health protective
remediation objectives.
Tier 1 sets forth separate remediation objectives for residential and industrial/commercial
used. Similarly, Tier 2 has separate equations for developing remediation objectives for residential
and industrial/commercial uses which reflect the different exposure rates expected for each land
use. The remediation objectives for industrial/commercial property are premised upon a lower
exposure rate, and therefore are less stringent than those established for residential property.
Accordingly, an industrial/commercial designation under any tier requires an accompanying
institutional control to assure that the land use is appropriately restricted to that property
classification. Furthermore, because the rules as currently proposed do not reflect consideration of
the appropriate exposure expected for a conservation or agricultural land use designation, these
designations require a Tier 3 demonstration based on individual site use characteristics to assure
appropriate protection of human health and the environment.
Section 742.120 sets forth the requirement that the applicant perform a site characterization
prior to developing remediation objectives pursuant to TACO in order to establish the extent and
concentrations of contamination at the site. The site investigation must be conducted in accordance
12
with the requirements of the governing program. The TACO rules therefore do not set forth a
separate site investigation procedure.
Subpart B: General
Subpart B of the rules contains general sections including definitions, a severability clause,
and incorporations by reference. Additionally, Subpart B sets forth procedures for determining the
soil attenuation capacity, the soil saturation limit, and demonstrating compliance with remediation
objectives. These procedures apply across the entire TACO process. Finally, Subpart B contains
the general rule that submittals to the Agency and subsequent review and approval by the Agency
are to be done in accordance with the governing program’s rules.
Definitions. Section 742.200 sets forth the definitions of terms used in these proposed
rules. Most of these are self-explanatory, however several warrant further discussion.
The definition of the term “carcinogen” repeats the statutory language from Section 58.2 of
the Act. This definition requires that contaminants that fall into any of the following categories be
considered carcinogens: 1) Category A1 or A2 carcinogens, as defined by the American
Conference of Governmental Industrial Hygienists, 2) Category 1 or 2A/2B carcinogens, as defined
by the World Health Organization’s International Agency for Research on Cancer; 3) a “Human
Carcinogen” or “Anticipated Human Carcinogen,” as defined by the United States Department of
Health and Human Service National Toxicological Program; or 4) a Category A or B1/B2
carcinogen as defined by the United States Environmental Protection Agency in its Integrated Risk
Information System (IRIS), or a final rule issued in a Federal Register notice by the USEPA.
Because the USEPA Soil Screening Level Guidance, which the Agency relied upon in developing
the Tier 1 Tables for soil remediation objectives, includes Category C carcinogens within its
definition of “carcinogens,” the Agency recalculated the soil remediation objectives for those
contaminants classified as Category C carcinogens by USEPA. The Board agrees that this properly
reflects the statutory intent.
At the Board’s request, the Illinois Department of Transportation (IDOT) introduced into
the record the definitions of the terms “highway,” “highway authority,” and “right of way” from
the Illinois Highway Code. (See Dec. 10, 1996 Transcript at 114 - 115.) The Agency proposed
that these definitions be included in the proposed rules in its Errata Sheet No. 2. The Board
believes that including these definitions in the rules clarifies these terms and ensures consistency in
their application and, therefore, adopts the proposed definitions into the proposal.
The definition of “residential property” proposed by the Agency paraphrased the statutory
language for Section 58.2 of the Act. The Agency’s proposed definition reads:
“Residential Property” means any real property that is used for habitation by individuals or
properties where children have the opportunity for exposure to contaminants through
ingestion or inhalation at educational facilities, health care facilities, child care facilities or
playgrounds.
Based upon the reasons further explained at pages 33-35,
supra,
the Board finds that the
Agency’s proposed definition requires further clarification. The Board adopts today a slightly
13
modified definition for Part 742, as well as in Part 740 in the R97-11 rulemaking, to more closely
reflect the statutory intent. The Board’s definition adds to the Agency’s definition the term “soil”
as a modifier to “ingestion, and replaces “playgrounds” with “outdoor recreational areas”. The
Board’s definition reads as follows:
“Residential Property” MEANS ANY REAL PROPERTY THAT IS USED FOR
HABITATION BY INDIVIDUALS, or where children have an opportunity for
exposure to contaminants through soil ingestion or inhalation at an educational
facilities, health care facilities, child care facilities, or outdoor recreational areas.
Soil Attenuation Capacity and Saturation Limit. Section 742.215 requires that the
concentrations of organic contaminants remaining in the soil not exceed the attenuation capacity of
the soil and sets forth the method for determining soil attenuation capacity.
The requirement that the soil attenuation capacity not be exceeded is intended to insure the
integrity of the soil remediation objectives established under the tiered approach, since the models
which are used to derive the soil remediation objectives do not account for the existence of free
product. Contaminant transport models generally assume equilibrium between contaminants that
adhere to soil particles and contaminants that dissolve in water in the soil pores. This assumption is
violated if the soil attenuation capacity is exceeded; then the models cannot accurately predict the
behavior and movement of contaminants. (See Exh. 4 at 3-5.) Furthermore, John Sherrill testified
that the requirement that the soil attenuation capacity not be exceeded will achieve three objectives.
First, it will ensure that there will be no migration of mobile free products. Second, it will protect
against potentially unacceptable health risks from accidental exposure to contamination left in place
which might occur if an engineered barrier or institutional control is breached. Finally, it will
provide a ceiling on the level of exposure from high contaminant concentrations from multiple
organic contaminants. (Dec. 2, 1996 Transcript at 151-152.)
Similarly, because the models which are used to derive the soil remediation objectives do
not account for the existence of free product, Section 742.220 provides two circumstances under
which remediation objectives cannot exceed the soil saturation limit (C
sat
). The soil saturation limit
is defined in Section 742.200 as “the contaminant concentration at which soil pore air and pore
water are saturated with the chemical and the adsorptive limits of the soil particles have been
reached.” Pursuant to Section 742.220, the applicant must ensure that the soil saturation limit is
not exceeded when establishing a Tier 2 or Tier 3 remediation objective for the inhalation exposure
route for an organic contaminant with a melting point below 30
o
C, or when establishing a Tier 2 or
Tier 3 remediation objective for the soil component of the groundwater ingestion exposure route for
any organic contaminant.
Section 742.220 establishes three methods for determining the soil saturation limit. These
methods are: 1) use of the chemical-specific default values set forth in Appendix A, Table A; 2)
use of a value derived from Equation S29 in Appendix C, Table A; or 3) use of a value derived
from another method approved by the Agency.
Compliance with Remediation Objectives. Section 742.225 sets forth the method for
demonstrating compliance with remediation objectives. For groundwater remediation objectives,
14
compliance with remediation objectives is demonstrated by comparing discrete samples to the
applicable groundwater remediation objective. The location of groundwater sampling points is
determined in accordance with the requirements of the governing program pursuant to which
remediation is being conducted.
Similarly, compliance with soil remediation objectives can be demonstrated by comparing
discrete samples of contaminant concentrations to the applicable soil remediation objective, unless
the applicant elects to composite or average soil samples in accordance with subsections (c) and (d)
of this section, as explained below. Again, the number of locations is determined by the governing
program.
Subsection (c) of Section 742.225 sets forth the requirements and limitations applicable to
compositing or averaging soil samples for the soil component of the groundwater ingestion
exposure route. For contaminants other than volatile organic compounds (VOCs), discrete samples
from the same boring may be composited or averaged. For VOCs, discrete samples from the same
boring may be averaged but compositing of samples is not allowed. This is because compositing
would tend to allow VOCs to volatilize and escape and the sampling would thus underestimate the
presence of volatile contaminants of concern in the soil. A minimum of two sampling locations for
every 0.5 acres of contaminated area is required, with discrete samples at each location taken at
every two feet of depth, beginning six inches below the ground surface, and continuing through the
zone of contamination. Samples may not be taken from below the water table.
Subsection (d) of Section 742.225 sets forth the requirements and limitations applicable to
compositing or averaging soil samples for the inhalation or ingestion exposure routes. As proposed
at First Notice, this section contained detailed requirements for the number and location of samples
to be taken. However, in response to comments, the Agency proposed that the detailed
compositing and averaging requirements be replaced with a requirement that each applicant submit
a sampling plan for the Agency to approve based upon site-specific information. This was much
the same as the alternative approach originally provided at Section 742.225(f). Accordingly, the
Agency proposed that the latter be deleted as redundant.
The Board accepts both modifications proposed by the Agency. The reasons for that
decision are set forth at pages 35-36
,
supra
. With the revisions to Section 742.225, the
compositing and averaging requirements will be established on a site-specific basis, based upon a
sampling protocol approved by the Agency.
Pursuant to Section 742.225(e), for the purposes of calculating averages under Section
742.225, if no more than 50 percent of the samples are reported as non-detect or below detection
limits, such results must be included in the sampling results as one-half of the reported detection
limit for the contaminant. If more than 50 percent are reported as non-detect, the applicant must
obtain Agency approval for an alternate procedure which is statistically valid for determining the
average.
Section 742.230 returns to the more general format of Subpart B. An omnibus provision,
Section 742.230 addresses Agency review and approval of submittals. This section makes clear
that the applicant must submit documents and requests in accordance with the governing program
15
under which the remediation is being addressed and the Agency will review and approve the same
in accordance with the governing program.
Subpart C: Exposure Route Evaluations
Subpart C sets forth the requirements and methodologies for determining and evaluating the
following exposure routes: inhalation, soil ingestion, and groundwater ingestion. The rules allow
the applicant to exclude from consideration contaminants of concern for one or more exposure
routes if the applicant demonstrates that the identified exposure route is not available for that
contaminant. The principle underlying the pathway exclusion is different from that underlying the
development of numeric remediation objectives. It is premised on the concept that an exposure
route must exist which enables a contaminant to reach a receptor for the contaminant to present a
threat to human health. Thus, Agency witness Mr. Gary King testified that pathway exclusion is
based on effective source control, coupled with site conditions and an appropriate institutional
control that effectively prohibits human exposure through a given pathway. (Exh. 2 at 4.) The
rules set forth five general criteria, as well as exposure route-specific criteria, which must be
satisfied to exclude an exposure route for a particular contaminant of concern.
General Criteria for Exclusion of Pathways. There are five general criteria which must be
satisfied before any exposure route may be excluded from consideration. These criteria are
intended to insure that the contamination left in place when the pathway is excluded will not present
a threat to human health. The first two criteria, set forth in Sections 742.305(a) and (b), require
that the soil attenuation capacity and the soil saturation limit capacity not be exceeded, as set forth
in Section 742.215 and 742.220, respectively. These criteria are intended to insure that there is no
free product present and to insure that the behavior of the contaminants can be accurately modeled.
Criteria three through five, set forth in Sections 742.305(c) through (e), require the
applicant to insure that the contaminated soil which remains in place will not exhibit the hazardous
characteristics of reactivity, corrosivity, or toxicity. Section 742.305(c) requires that any soil that
contains contaminants of concern cannot exhibit any of the characteristics for reactivity for
hazardous waste, as determined under 35 Ill. Adm. Code 721.123. Section 742.305(d) requires
that any soil that contains contaminants of concern cannot exhibit a pH less than or equal to 2.0, or
greater than or equal to 12.5. Finally, Section 742.305(e) requires that any soil that contains one or
more of the inorganic chemicals arsenic, barium, cadmium, chromium, lead, mercury, selenium,
silver, or the salts of any of these chemicals cannot exhibit characteristics of toxicity. The toxicity
determination is made pursuant to the methods set forth at 35 Ill. Adm. Code 721.124.
Jenner & Block expressed concern regarding the proposed pathway exclusion
requirements. The Agency disagreed with Jenner & Block and asked that the Board not make
any changes to Subpart C. Each of these concerns is addressed in detail at pages 36-38,
supra
.
For the reasons given there, the Board adopts Subpart C as proposed by the Agency without
the modifications advocated by Jenner & Block. Additionally, the Board has made a number
of non-substantive format changes in Sections 742.310 and 742.315 for purposes of clarity.
Specific Criteria for Exclusion of Pathways. Sections 742.310, 742.315 and 742.320 set
forth the specific criteria which must be satisfied to exclude from consideration each particular
16
pathway,
i.e.
, inhalation, soil ingestion, and groundwater ingestion respectively. These criteria
must be satisfied in order to exclude the applicable exposure route, in addition to the five general
criteria set forth in Section 742.305.
Section 742.310 sets forth additional criteria which must be satisfied in order to exclude the
inhalation exposure route for contaminants of concern. In order to exclude this exposure route, the
concentration of any contaminant of concern within ten feet of the land surface or any man-made
pathway cannot exceed the Tier 1 remediation objective for the inhalation exposure route.
Alternatively, the applicant can install an engineered barrier, as set forth in Subpart K, which is
approved by the Agency. The applicant must also obtain an institutional control, in accordance
with the requirements of Subpart J, which ensures compliance with these requirements and ensures
the safety of construction workers.
Section 742.315 sets forth additional criteria which must be satisfied in order to exclude the
soil ingestion exposure route for contaminants of concern. To exclude this pathway, the applicant
must demonstrate that the concentration of any contaminant of concern within three feet of the land
surface does not exceed the applicable Tier 1 remediation objective or that an engineered barrier has
been installed, in accordance with the requirements of Subpart K and approved by the Agency.
Furthermore, the applicant must obtain an institutional control which ensures that these
requirements are met and ensures the safety of construction workers.
Section 742.320 sets forth the additional criteria which must be satisfied in order to exclude
the groundwater ingestion exposure route from consideration. These criteria include location and
groundwater quality demonstrations, as well as a requirement that an institutional control,
i.e.
an
ordinance adopted by the local government, be in place. Taken together, these criteria are intended
to ensure that potable drinking water supplies will not be impacted by contamination left in place.
Specifically, the applicant must demonstrate that corrective action measures have been
completed to remove any free product. The applicant must also demonstrate that the source of the
release is not located within the minimum or designated maximum setback zone or within a
regulated recharge area of a potable water supply well. The applicant must also demonstrate that
the concentration of any contaminant of concern in the groundwater within the minimum or
designated maximum setback zone of an existing water supply well meets the applicable Tier 1
groundwater remediation objectives. Finally, the applicant must demonstrate that the concentration
of any contaminant of concern in groundwater which discharges to a surface water will meet the
applicable surface water quality standards under 35 Ill. Adm. Code 302. These last two
demonstrations must be made using Equation R26 in Appendix C, Table C.
In order to exclude the direct ingestion of groundwater pathway, in addition to satisfying the
location and groundwater quality demonstrations, the applicant must demonstrate, in accordance
with Subpart J: Institutional Controls, that the unit of local government has adopted an ordinance
that effectively prohibits the installation or use of groundwater as a potable supply of water. Such
an ordinance must be in effect for any area within 2500 feet of the source of the release. As
originally proposed by the Agency, the ordinance did not have to prohibit the use of the potable
water supply well by the unit of local government. Subsequent to hearing, the Agency explained its
belief that the rule needs to be modified to insure that public potable water supply wells, as well as
17
private wells, do not unwittingly tap into a contaminated source. The Agency proposed that unit of
local government must enter into a Memorandum of Understanding (MOU) with the Agency if the
local ordinance used as an institutional control does not prohibit the local government from
installing and using a potable water supply well. The MOU must commit the local government to:
1) keep a registry of sites within its boundaries that have received no further remediation
determinations; 2) consider whether groundwater contamination from those sites may be present at
potential public well sites; and 3) take appropriate protective measures if wells are sited near such
locations. (PC 15 at 5-6; Errata Sheet No. 2.)
The Board agrees with the revisions proposed by the Agency. Subsection (d) of Section
742.320 now cross-references Section 742.1015 of Subpart J, and the modifications proposed by
the Agency at that section still allow ordinances which do not prohibit the installation or use of
potable water supply wells by local governments to be used as institutional controls, but only if the
local government has entered into a MOU with the Agency. (See pages 31-32,
supra
, for a further
discussion of the ordinance requirements under Section 742.1015.)
Subpart D: Determining Area Background
This subpart sets forth the procedures for determining area background concentrations
for contaminants of concern. As set forth in Section 58.5(b) of the Act, applicants shall not be
required to remediate contaminants of concern to levels that are less than area background
levels, subject to two statutory exceptions which have been included in the rules at Section
742.415. First, if the contaminant concentration is equal to or less than the area background
level, yet it exceeds the Tier 1 residential level, the property cannot be converted to residential
use unless that remediation level or an alternative developed under Tier 2 or Tier 3 is
achieved. (Section 58.5(b)(2) of the Act.) Second, if the Agency determines in writing that
the area background level poses an acute threat to human health or the environment in
consideration of the post-remedial land use, appropriate risk-based remediation levels must be
developed. (Section 58.5(b)(3) of the Act.) If neither of these exceptions applies, and the
applicant can demonstrate that contaminant concentrations are at area background levels, no
further remediation is required. Another use of area background levels is for the applicant to
demonstrate that area background levels should be used as the remediation objectives for
contaminants of concern. This alternative is limited to industrial/commercial properties only,
and accordingly requires the use of an institutional control.
Determination of Area Background for Soils. Section 742.405 sets forth the method
for determining area background for soils. Subsection (a) sets forth the sampling
requirements. Section 742.405(b) sets forth the two options available to the applicant for
determining the area background level for inorganics. The first option is referred to as the
statewide area background approach. This approach relies upon data previously compiled by
the Agency concerning area background concentrations throughout the State, which is set forth
in Appendix A, Table G. Under the statewide area background approach, the applicant must
set the upper limit of the area background concentration for the site at the value of the
concentrations of inorganic chemicals in background soils listed in Appendix A, Table G. The
applicant’s second option is to use another method which is statistically valid for the
characteristics of the data set and which has been approved by the Agency.
18
Determination of Area Background for Groundwater. Section 742.410 sets forth the
method for determining area background concentrations for groundwater. Subsection (a) sets
forth the sampling requirements and is intended to ensure that the sampling points are of
sufficient quantity and appropriately located so as to be representative of actual background
concentrations. Section 742.410(b) sets forth the two options available to the applicant for
determining background levels for groundwater. The first option is referred to as the
“Prescriptive Approach”; the second option is the use of another statistically valid approach
which is appropriate for the data set and approved by the Agency.
Under the Prescriptive Approach, the upper limit of the area background concentration
for the site is set at the Upper Tolerance Limit (UTL) for sample sets of ten samples or more,
or at the maximum value of the sample set for sets of less than ten samples. The Prescriptive
Approach establishes the method for determining the UTL of a normally distributed sample. If
the sample set contains less than fifty (50) samples, the applicant must use the Shapiro-Wilke
Test of Normality to determine whether the sample set is normally distributed. The
Prescriptive Approach can only be used if the samples are determined to be normally
distributed.
The Prescriptive Approach cannot be used if more than 15 percent of the groundwater
sampling results for any chemical are less than the appropriate detection limit for that
chemical. If 15 percent or less are less than the appropriate detection limit, a concentration
equal to one-half the detection limit must be used for that chemical in the calculations.
Additionally, the Prescriptive Approach cannot be used for determining area background for
pH. For these exceptions and in any case, Section 742.410(b) concludes with the provision
that another statistically valid approach may be used on a site-specific basis if approved by the
Agency.
Pursuant to Section 742.415, area background concentrations can be used in two ways.
First, an area background concentration can be used to support a request to exclude a chemical
as a contaminant of concern from further remediation due to its presence as a result of
background conditions. Second, an area background concentration can be used as the
remediation objective for a contaminant of concern. For either of these to occur the applicant
must submit the request to the Agency. Again, however, pursuant to Section 58.5(b)(3) of the
Act, area background cannot be used in either manner if the Agency determines, in writing,
that the background level poses an acute threat to human health or the environment taking into
consideration the post-remedial land use of the site.
At hearing, three issues were raised regarding area background. The three issues are:
1) exclusion of a contaminant of concern based on area background; 2) substitution of area
background for Tier 1 residential objectives if the naturally occurring background level of a
contaminant of concern is greater than the Tier 1 residential level; and 3) the propriety of
changing Appendix A, Table G to use the 50
th
percentile values versus the 90
th
percentile
values from the Agency’s area background database. For further discussion on each of these
19
issues, see pages 40-43,
supra.
The Board will adopt the area background requirements as
proposed by the Agency and modified pursuant to its subsequent filings.
Subpart E: Tier 1 Evaluation
A Tier 1 evaluation compares the concentrations of contaminants of concern to
established baseline remediation objectives which are set forth in Appendix B, Tables A
through E. The Tier 1 objectives are numerical chemical concentrations that represent a level
of contamination at or below which there are no human health concerns for the designated land
use. The Tier 1 objectives for individual chemical contaminants do not exceed an excess
cancer risk of 1 in 1,000,000 for carcinogens (also referred to as 1 x 10
-6
), or a hazard
quotient
3
of 1 for noncarcinogens. The pre-established remediation objectives under Tier 1 are
based upon the SSL and the screening levels therein are designed to insure that contaminants of
concern individually will not present a greater risk. However, in some instances where
multiple contaminants are present at a site, the cumulative effect of similar-acting chemicals
may cause the target risk of 1 x 10
-6
or the hazard quotient of 1 to be exceeded. To correct
this, the rules adopted today include a mixture rule which provides that remediation objectives
developed under Tier 1 for the groundwater ingestion exposure route must take into account
the cumulative effect of noncarcinogens affecting the same target organs at a site.
In order to allow consideration of the proposed land use for the site, different
objectives are set forth for different receptor populations: residential, industrial/commercial,
and construction workers. Where the remediation objectives are based on an
industrial/commercial property use, institutional controls must be adopted in accordance with
Subpart J to ensure that the land use is appropriately restricted. The applicant need not further
evaluate an exposure route if all contaminants of concern are below Tier 1 values for that
exposure route, with the one exception for groundwater remediation objectives.
The Tier 1 remediation objectives are set forth in Appendix B, Tables A through E.
These tables set forth remediation objectives for 117 chemicals. The tables are generally
divided into two groups: those applicable to soil remediation objectives, and those applicable
to groundwater remediation objectives. The groundwater component and the soil component
of the groundwater ingestion route are further divided into objectives for Class I or Class II
groundwater.
Tier 1 Soil Remediation Objectives. Under Tier 1, the applicant must consider two
different direct exposure routes for soil when establishing remediation objectives pursuant to
the TACO approach: the inhalation exposure route and the ingestion exposure route.
3
“Hazard Quotient” is defined as the ratio of a single substance exposure level over a specified
time period to a reference dose for that substance derived from a similar exposure period. The
reference dose, which is derived for noncarcinogens as an acceptable daily chemical exposure,
is that dose at which no harmful consequences occur. A hazard quotient greater than 1
signifies a potential adverse effect, since a value greater than one occurs when a chemical
exposure is measured to be greater than the reference dose.
20
Additionally, the applicant must consider the soil component of the groundwater ingestion
route. Because these objectives are considered sufficiently protective, the applicant need not
examine the dermal contact exposure route under Tier 1. The Tier 1 soil remediation
objectives are set forth in Appendix B, Tables A, B, C, and D. The mixture rule adopted
today for similar-acting chemicals is not applicable to these remediation objectives.
Appendix B, Table A sets forth the soil remediation objectives based upon residential
property use, for the soil ingestion exposure route, the inhalation exposure route, and the soil
component of the groundwater ingestion exposure route. Where appropriate, Table A also sets
forth the Acceptable Detection Limit (ADL).
4
Because the Tier 1 residential levels are based
upon protection in a residential exposure scenario, they are considered sufficiently protective
that it is not necessary to establish separate remediation objectives for construction workers.
Appendix B, Table B sets forth the Tier 1 soil remediation objectives based upon
industrial/commercial property use. As for the residential remediation objectives in Table A,
separate remediation objectives are established for the soil ingestion exposure route, the
inhalation exposure route, and the soil component of the groundwater ingestion exposure
route. For the soil ingestion exposure route and the inhalation exposure route, separate
remediation objectives are established for two receptor populations: the industrial/commercial
population and the construction worker population. For the soil component of the groundwater
ingestion exposure route, separate remediation objectives are established for Class I and Class
II groundwaters.
The Tier 1 objectives for the soil ingestion and inhalation pathways were derived using
the SSL with modifications as necessary to comply with Illinois law. The SSL was developed
by USEPA for use in the Superfund program as a mechanism for screening out sites which do
not require further study or action. The screening levels in the SSL are soil concentrations at
or below which there is no concern in the Superfund program that some type of further action
is required. They were developed based on a conceptual site model of a one-half acre site,
with contamination extending to the water table, upon which a future residence with a private
well would be built. (December 2, 1996 Transcript at pages 52-54; Exh. 5 at 11.)
Again, the screening levels in the SSL are designed to insure that the contaminants of
concern individually will not present a greater than 1 in a million excess cancer risk for
carcinogens or have a hazard quotient greater than 1. Since the SSL is based on an anticipated
residential use, the Tier 1 remediation objectives for the industrial/commercial and
construction workers had to be calculated from the SSL equations using the different exposure
assumptions appropriate for these populations.
4
ADL is defined at Section 742.200 to mean the detectable concentration of a substance which
is equal to the lowest appropriate Practical Quantitation Limit (PDL). PDL is defined as the
lowest concentration that can be reliably measured within specified limits of precision and
accuracy for a specific laboratory analytical method during routine laboratory operating
conditions. See Section 742.200 for these definitions in their entirety.
21
The Tier 1 objectives for the soil component of the groundwater ingestion route were
derived from two different sources. For organic chemical contaminants, the Tier 1 objectives
were derived using SSL equations with separate objectives established for Class I and Class II
groundwaters. For inorganics, the proposed Tier 1 objectives establish two alternative
approaches to setting soil objectives for the soil component of the groundwater ingestion route.
As proposed by the Agency, the first alternative is based on the Toxicity Characteristic
Leaching Procedure (TCLP) test. The second alternative is to allow pH-specific remediation
objectives. The Board notes that the rules as proposed by the Agency, do not contain any
requirement that the TCLP test be used. Reference to this test is limited to footnote “m” in
the Tier 1 tables at Appendix B, Tables A and B.
The TCLP method was carried over by the Agency from the Underground Storage
Tank program. Under this approach, the remediation objective is the same as the Part 620
groundwater quality standard for the chemical of concern for the applicable groundwater
classification. As proposed at First Notice, these remediation objectives were listed as mg/L
concentrations for the TCLP test. The applicant must perform a TCLP analysis on a soil
sample from the site and compare the concentration of the inorganic chemical of concern in the
TCLP extract to the applicable groundwater standard.
Jenner & Block questioned the propriety of the TCLP in this context, and presented
testimony in support of a different test, the Synthetic Precipitation Leaching Procedure
(SPLP). This test has been adopted by the USEPA for determining compliance with
remediation objectives. It is designed to mimic the pH of rainwater that percolates through a
contaminated site. Jenner & Block gave several other reasons why it prefers to use the SPLP
over the TCLP.
(January 15, 1997 Transcript and January 16, 1997 Transcript at pages 237-
250; Exh. 18 at 7.)
After studying the issue, the Board finds either test is acceptable. Accordingly, Section
742.510(a)(4) has been added which allows the use of the SPLP or
the TCLP to evaluate the
soil component of the groundwater ingestion exposure route. This language also removes the
ambiguity in the Agency proposal due to the lack of any straightforward requirement that the
TCLP test be used for the listed inorganics. Additionally, an applicant still may evaluate the
soil component on the basis of the total amount of contaminant in the soil sample result. This
alternative has been relocated to subsection (a)(5) of Section 742.510.
The second alternative for establishing soil objectives for the soil component of the
groundwater ingestion allows the applicant to establish pH-specific remediation objectives
appropriate for the conditions at the site. (Exh. 5 at 20.) In addition to inorganics, this
alternative may be used to establish remediation objectives for certain ionizable organics. The
pH-specific objectives for Class I and Class II groundwaters are set forth in Appendix B,
Tables C and D, respectively. These alternative remediation objectives allow the applicant to
elect to evaluate the soil component of the groundwater ingestion exposure route based on the
total amount of contaminant in a soil sample result, rather than the TCLP or SPLP analysis.
In order to use this alternative approach, the applicant must determine the soil pH at the site
and then select the appropriate soil remediation objectives based on Class I and Class II
22
groundwaters. This method cannot be used if the soil pH is less than 4.5 or greater than 8.0.
This alternative now appears at Section 742.510(a)(5) with minor modifications to the
language originally proposed by the Agency.
The Agency proposed separate soil remediation objectives based on pH for identified
ionizable organics or inorganics because the solubility of metals in water is highly dependent
on pH of the solution. (See Section 742.505(a)(3)(C).) Generally, at lower pH, all metals are
more soluble than at higher pH. To account for this phenomenon, the proposed standards have
tables (Appendix B, Tables C and D) that list inorganic and ionizable organic compounds for
pH values ranging from 4.5 to 8.0 in nine intervals of 0.25 increments. There are 15 metals
and eight organic compounds listed in each table. There are separate tables for Class I and
Class II groundwater.
Finally, pursuant to Section 742.510(a)(6), the applicant must review the soil
remediation objectives determined for each remaining exposure routes, and select the most
stringent of those remediation objectives, and then compare that one to the soil concentrations
measured at the site. When using Appendix B, Table B for evaluating industrial/commercial
properties, the remediation objectives for the ingestion and inhalation exposure routes shall be
the more stringent of the industrial/commercial populations and the construction worker
populations. If the soil remediation objective for a chemical is less than the ADL, the ADL
shall serve as the remediation objective. Based upon this analysis, the applicant will be able to
identify the applicable soil remediation objective under a Tier 1 evaluation.
Tier 1 Groundwater Remediation Objectives. Identifying the applicable groundwater
remediation objective is more straightforward. Appendix B, Table E contains the groundwater
remediation objectives for the groundwater component of the groundwater ingestion exposure
route. The table contains separate values for Class I and Class II groundwaters and therefore
the applicant must determine the Part 620 classification for groundwater at the site. The
applicant must then compare the concentrations of groundwater contaminants at the site to the
applicable Tier 1 groundwater remediation objectives set forth in Table E. Because this
exposure route is based on direct ingestion of groundwater, an exposure route which is not
impacted by the land use at the site, no distinction is made between residential and
industrial/commercial use.
For any contaminants of concern not listed in Appendix B, Tables A through E, the
applicant may request site-specific remediation objectives from the Agency, or propose site-
specific objectives in accordance with 35 Ill. Adm. Code 620, Tier 3 at Subpart I of TACO, or
both.
The Agency proposed, in its final comments, the addition of a new provision at Section
742.505(b)(3) to address the effect of mixture of similar-acting chemicals under Tier 1. The
new provision, which applies only to remediation of Class I groundwater, states that for
mixtures of similar-acting chemicals listed in Appendix A Tables E (noncarcinogens) and
23
Table F (carcinogens), the requirements of 35 Ill. Adm. Code 620.615 regarding mixture of
chemicals need to be met at the point of human exposure.
5
(PC 10 at 11.)
Subsequent to filing its final comments, in a filing entitled “Motion to File Instanter
Additional Language”, the Agency suggested the addition of certain procedures under Section
742.505(b)(3) to be used to show that mixtures of similar-acting chemicals in Class I
groundwater do not present unacceptable risks to users of the groundwater. (February 25, 1997
Transcript at 1; PC 17; Exh. 1.)
The Agency’s arguments on this issue convince the Board that a more limited version
of the mixture rule is necessary at this time. A more detailed discussion of the arguments in
support of a mixture rule and the Board’s consideration of the same appears below at pages 46-
50. At this time, the Board concludes that such a mixture rule,
for noncarcinogenic chemicals
only
, is necessary to protect human health and the environment. Accordingly, the Board
incorporates such a rule at Section 742.505(b) applicable only to groundwater remediation
objectives.
Subpart F: Tier 2 General Evaluation
Under Tier 2, the applicant can develop soil and groundwater remediation objectives
applying site-specific information to pre-established modeling equations. The Tier 2 equations
are set forth in Appendix C, Tables A and C. These equations are from the SSL and the
RBCA approaches. See Appendix C, Tables A and C, respectively for the equations to be
used. The values to be used in the calculations, and the appropriate units are found at
Appendix C, Tables B and D. Table B contains the values for use in the SSL equations, and
Table D contains the values for the RBCA equations. These tables also contain the acceptable
exposure factors for the residential, industrial/commercial and construction worker populations
when the present and post-remediation land uses are evaluated. As in Tier 1, the remediation
objectives in Tier 2 cannot exceed an excess cancer risk of 1 in 1,000,000 for carcinogens, or
a hazard quotient of 1 for noncarcinogens. Additionally, as in Tier 1, there is a mixture rule
requiring that the cumulative effect of similar-acting noncarcinogenic chemical be evaluated in
developing remediation objectives. However, unlike Tier 1, this rule is applicable to soil as
well as groundwater remediation objectives.
The rules generally applicable to a Tier 2 evaluation are set forth at Section 742.600.
Similar to a Tier 1 analysis, the soil saturation and soil attenuation capacity restrictions found
at Subpart B: Sections 742.215 and 742.220 apply. In other words, free product must be
removed. See subsections (d)(1) and (3) of Section 742.600. Section 742.600 also instructs
the applicant about how to choose the correct remediation objective if there is more than one
exposure route requiring a remediation objective. This selection process is described at
5
The Agency also added a provision at Section 742.805(c), which requires the consideration of
the effect of mixtures of similar-acting chemicals in determining Tier 2 groundwater
remediation objectives. Section 742.805(c) provides a cross-reference to the provisions of
Section 742.505(b)(3). Section 742.805(c) is adopted today under Tier 2.
24
Section 742.600(e), (f), and (g), and presumes that the applicant has chosen to forgo the Tier 1
fixed numerical remediation objectives.
At the December 3, 1996 hearing, John Sherrill, a witness for the Agency, gave
examples demonstrating when to use a Tier 1 or 2 remediation objective. For the purposes of
illustration, the remediation objectives for benzene are used. The groundwater is Class I, none
of the exposure routes are excluded and the numbers from Appendix B, Table A are used.
The remediation objective for benzene for the ingestion route is 22 mg/kg, for the inhalation
route is 0.8 mg/kg, and the migration to groundwater route is 0.03 mg/kg. The migration to
groundwater remediation objective applies as the Tier 1 soil remediation objective because it is
the most stringent out of the three values. If the calculated Tier 2 soil remediation objective
for an exposure route is more stringent than the Tier 1 remediation objective for the same
exposure route, then the Tier 1 remediation objective applies. In the hypothetical, within Tier
2, the applicant calculates a soil remediation objective of 0.02 mg/kg. The remediation
objective would then be 0.03 mg/kg because it is less stringent than the calculated Tier 2 soil
remediation objective.
If the calculated Tier 2 soil remediation objective for an exposure route is more
stringent than one or more of the Tier 1 soil remediation objective(s) for a different exposure
route, then the calculated Tier 2 soil remediation objective applies and the Tier 2 remediation
objective for other exposure routes do not need to be calculated. For example, within Tier 2,
the applicant calculates a migration to groundwater remediation objective of 0.1 mg/kg. The
remediation objective would then be 0.1 because it is more stringent than the Tier 1 ingestion
and inhalation remediation objectives (22 mg/kg and 0.8 mg/kg respectively).
If the calculated Tier 2 soil remediation objective is less stringent than one or more of
the Tier 1 soil remediation objectives for the remaining exposure routes, then the other Tier 2
remediation objectives are calculated and the most stringent calculated Tier 2 value applies.
Within Tier 2, the applicant calculates a migration to groundwater remediation objective of 1.2
mg/kg. This is less stringent than the inhalation soil remediation objective in Tier 1. So the
applicant then calculates the Tier 2 ingestion and inhalation remediation objectives. The
applicant calculates an ingestion remediation objective of 30 mg/kg and an inhalation
remediation objective of 11 mg/kg. Since the Tier 2 migration to groundwater remediation
objective is the most stringent (1.2 is less than 30 and 11), 1.2 mg/kg is the remediation
objective.
As in Tier 1, the proposed land use for the site is considered in establishing Tier 2 soil
remediation objectives. In a Tier 2 evaluation, the proposed land use for the site will
determine the appropriate exposure factors contained in the applicable equation. The
appropriate exposure factors for residential, industrial/commercial, and construction worker
populations are set forth in Appendix C, Tables B and D. The established exposure factors
can only be varied in a Tier 3 analysis. If a Tier 2 evaluation is based on an
industrial/commercial property use, the construction worker scenario must also be evaluated.
Additionally, the applicant must obtain an institutional control in accordance with the
requirements of Subpart J.
25
Finally, the Agency requested that the mixture rule originally proposed for Tier 2 as a
single rule be replaced with two separate sections, one addressing soil remediation objectives
and the other addressing groundwater remediation objectives. The Board accepts these
revisions as nonsubstantive. Accordingly, the Board deletes Section 742.610 and replaces it
with a mixture rule for soil at Section 742.720 and for groundwater at Section 742.805. For
further discussion of the mixture rules adopted for Tier 2, see pages 46-50
supra.
Subpart G: Tier 2 Soil Evaluation
Tier 2 provides the applicant with two options for establishing soil remediation
objectives: reliance on the SSL equations or on the RBCA equations. Because the RBCA
equations combine the soil ingestion, inhalation of vapors and particulates, and dermal contact
exposure routes, while the SSL equations treat the soil ingestion, inhalation of volatiles, and
inhalation of fugitive dust exposure routes separately, the applicant must choose only one of
these approaches, and the two approaches cannot be combined. However, both methods treat
the soil component of the groundwater exposure route separately, so the applicant can choose
to use either method to calculate the remediation objectives for this exposure route, no matter
which approach was used to establish the other soil objectives.
SSL Equations. The SSL equations are set forth in Appendix C, Table A. The
parameters for these equations are set forth in Appendix C, Table B. The equations are
divided into separate categories by exposure route: ingestion, inhalation of volatiles, inhalation
of fugitive dust, and to groundwater.
Within each exposure route’s set of equations, there are separate sets of equations for
noncarcinogens and carcinogens. The equations for carcinogens reflect an expected excess
cancer risk of 1 in 1,000,000, while the equations for noncarcinogens reflect a hazard quotient
of 1. Within these categories, separate equations are set forth for residential,
industrial/commercial, and construction worker populations. The different equations for each
type of land use reflects the expected differences in the exposure factor, exposure duration,
averaging time, and ingestion rate. Default values and parameters for these equations are
listed in Appendix C, Table B.
RBCA Equations. Appendix C, Table C contains the RBCA equations used in Tier 2.
The RBCA equations for establishing soil remediation objectives are separated into three
categories. The first two categories examine the combined exposures of soil ingestion,
inhalation of vapors and particulates, or dermal contact with soil, and ambient vapor inhalation
(outdoor) route from subsurface soils. The third category is for the migration to groundwater
pathway. Within each of these categories, separate equations are set forth for noncarcinogens
and carcinogens. Since RBCA offers two different ways to evaluate the soil remediation
objectives, the smaller, or more stringent, of the two values will be the remediation objective
(either equation R1 or R7 for carcinogens and equation R2 or R8 for noncarcinogens).
26
Unlike the SSL approach, which sets forth separate equations for each exposure route
for each type of land use, RBCA does not have separate equations for each type of land use.
Instead, RBCA allows for differences in the type of land use to be reflected in the values of
certain parameters. Because RBCA groups ingestion and inhalation into the same equations,
one model is to be used in Tier 2 for the inhalation and ingestion exposure routes. Either the
RBCA or SSL models can be used for the soil component of the groundwater exposure route.
The Board adopts the requirements originally proposed at Section 742.610 concerning
the cumulative effect of noncarcinogenic chemicals for soil remediation objectives at Section
742.720. Appendix A, Table E sets forth groups of chemicals from Appendix B, Tables A
and B, that have remediation objectives based on noncarcinogenic toxicity, and that affect the
same target organ. If more than one chemical detected at the site affects the same target
organ, the applicant must correct the initially calculated remediation value for each chemical in
the group.
Subpart H: Tier 2 Groundwater Evaluation
Subpart H contains the procedures for developing Tier 2 groundwater remediation
objectives. If the contaminants of concern exceed the applicable Tier 1 remediation objectives,
an applicant has several choices. As preliminary to a Tier 1 analysis, the applicant can as a
preliminary matter, demonstrate that the pathway is excluded, that the contamination is at or
below the area background concentration in accordance with Subpart D, or conduct Tier 3
analysis. There are also two alternatives distinctive to groundwater remediation objectives
available. An applicant can seek from the Board reclassification of the contaminated
groundwater pursuant to 35 Ill. Adm. Code 620.260, or an adjusted standard pursuant to
Section 28.1 of the Act. However, should an applicant choose to develop Tier 2 groundwater
remediation objectives, the applicant must use RBCA Equation R26. Using this equation, the
applicant can develop remediation objectives which exceed the applicable Part 620
groundwater standards at the site, but which will meet the applicable groundwater standards at
the point of human exposure.
Pursuant to Section 742.805, before developing a Tier 2 groundwater remediation
objective, the applicant must first identify the horizontal and vertical extent of the
contamination, and, to the extent practicable, take remedial action to remove any free product.
The applicant can then use RBCA Equation R26 to demonstrate that the applicable
groundwater standards will be achieved at the point of human exposure. The basis and
application of Equation R26 to predict impacts from remaining groundwater contamination are
explained in Section 742.810.
Equation R26 predicts the concentration of a contaminant along the centerline of a
plume, taking into account the three dimension dispersion and biodegradation. Using Equation
R26, the applicant can demonstrate that, although the concentration of a contaminant exceeds
the applicable Tier 1 objective at the source, the concentration at the point of human exposure
will meet either the applicable Tier 1 groundwater remediation objective, or if no Tier 1
objective exists, the applicable Health Advisory concentration as determined in accordance
with the procedures set forth in 35 Ill. Adm. Code 620, Subpart F. If the applicant determines
27
that the applicable Tier 1 objective will be exceeded at the point of human exposure, the
applicant can back-calculate the concentration that must be achieved at the source in order for
the compliance to be achieved.
In addition to demonstrating that the applicable Tier 1 objective will be achieved at the
point of human exposure, in order to demonstrate compliance pursuant to Tier 2, the applicant
must demonstrate that five additional requirements are satisfied. First, using Equation R26,
the applicant must demonstrate that the concentration of any contaminant in groundwater
within the minimum or designated maximum setback zone of an existing potable water supply
well will meet the applicable Tier 1 groundwater objective or the Health Advisory
concentration
6
. Second, the applicant must demonstrate that the source of the release is not
located within the minimum or designated maximum setback zone of a potable water supply
well. Third, the applicant must use Equation R26 to demonstrate that the concentration of any
contaminant in groundwater discharging into surface water will meet the applicable water
quality standard pursuant to 35 Ill. Adm. Code 302. Fourth, the applicant must demonstrate
that any groundwater remediation objective established pursuant to this procedure does not
exceed the water solubility for that contaminant. Finally, if the remediation relies on an
engineered barrier, the applicant must demonstrate that an institutional control is in place
requiring that the barrier remain in place. These requirements are set forth at Section 742.805
and illustrated at Appendix C: Illustration B.
During the public comment period, the Board received a public comment questioning
whether the R26 equation in the RBCA guidelines has been properly adapted for use in
establishing risk based remediation objectives under Tier 2. The commentator urged the Board
to change the last
erf
(error function) term in the denominator of Equation R26 from 4 to 2.
(PC 6.) The Agency supports the change. (PC 10 at 12-13; PC 22.)
The Board has reviewed the comments received on this issue and the various documents
supporting the R26 Equation. A more detailed discussion of the comments in support and
against changing Equation R26 at this time and the relevant guidance documents is set forth at
pages 50-52,
supra.
Since the supporting documents indicate that the use of the incorrect
number (4) for the vertical dispersion
erf
results in under-prediction of concentrations of
contaminants along centerline of a plume, the Board will correct Equation R26 by changing the
constant value for the
erf
relating to vertical dispersion from 4 to 2. Equation R15, which is
essentially the same equation, is also changed where it appears in the rules.
Section 742.810 contains another provision regarding the distance between an existing
potable water supply well and the source of contamination which was the subject of change
proposed first by the Agency, and later in public comments by IERG and ISG. The Agency
proposed in Errata Sheet No.1, in each subsequent errata sheet and in changes attached to its
public comments, that Section 742.810(b)(1) be revised as follows:
6
Health Advisory concentrations are established in accordance with 35 Ill. Adm. Code 620,
Subpart F for contaminants that do not have a groundwater quality standard under Part 620,
Subpart D.
28
To demonstrate that no existing potable water supply well is
adversely impacted, X shall be the distance from the down-gradient
edge of the source of contamination at the site to the nearest
water supply well minimum or maximum setback zone of an
existing potable water supply well...
In response, IERG proposes that the word “designated” be inserted prior to the word
“maximum” to convey that the minimum setback zone will be used unless a maximum setback
zone is determined. Minimum setback zones are established pursuant to Section 14.2(g) of the
Act and maximum setback zones are established on a site-specific basis. IPC and ISG state
that with the addition of that one word the presumption is clear that either the minimum or
maximum setback zone can be used, whichever is closer.
The Agency has no objection with the inclusion of the word “designated” prior to
“maximum”. Again, the Agency did not give a reason for the change it proposed in Errata
Sheet No. 1. Both believe that the minimum setback zone which is an established number in
the Act or a maximum setback zone which is ascertained from procedures set out in the Act
would be more correct to use given the purposes of setback zones. After reviewing the
Agency’s proposed language and the comments submitted by it and IERG, IPC, and ISG, the
Board will add the word “designated” before the word “maximum” to provide the desired
clarification.
In addition to the above change, the Board has modified the proposed language at
Section 742.810(b)(1) to clarify the procedure for demonstrating that no existing potable water
supply is adversely impacted by a remediation site. The Board notes that the initially proposed
language did not have any limitations regarding the location of potable water supply wells.
Essentially, the revisions to subsection (b)(1) require an applicant to calculate the distance “X”
from the downgradient edge of the source to the point where the contaminant concentration is
equal to the Tier 1 groundwater remediation objective or Health Advisory concentration. If
there are any potable water supply wells located within the distance X downgradient of the
source, then the applicable groundwater remediation objectives must be met at the edge of the
minimum or designated maximum setback zone. If no potable water supply wells exist within
the calculated distance X, then it can be determined that no potable water supply wells are
adversely impacted.
Subpart I: Tier 3 Evaluation
Tier 3 allows the applicant to develop remediation objectives using alternative parameters
not found in Tier 1 or Tier 2. It allows the applicant great flexibility in developing remediation
objectives appropriate for a particular site based upon site-specific information, rather than relying
on general categories of information. The options available under Tier 3 include: use of modified
parameters in the Tier 2 equations, use of alternative models, conducting a site-specific risk
assessment, use of probabilistic analysis and sophisticated fate and transport models, assessment of
impractical remediation, and variation of the target risk level. If any contaminants of concern are
found to exceed the remediation objectives developed using the Tier 3 analysis, the applicant would
29
be required to remediate the contamination until the objectives are achieved. The applicant must
provide appropriate justification for the use and application of any alternative parameters, models,
or analysis relied upon in a Tier 3 evaluation.
Under the Agency’s proposal, Tier 1 remediation objectives and Tier 2 equations are
based upon a one-in-a-million individual excess cancer risk for carcinogens and a hazard
quotient of one for noncarcinogens. (Exh. 4 at 12 & 21.) The Agency’s proposal allows for
changes in the target risk levels under Tier 3. As proposed by the Agency in Errata Sheet No.
2, Section 742.900(d) clearly set forth that requests for changes in target risk levels at the
point of human exposure level must be supported with a formal risk assessment conducted in
accordance with Section 742.915.
A number of the participants representing the regulated community expressed concerns
regarding the target risk levels. The main issue concerning the target risk levels is whether or
not the regulations should allow the determination of remediation objectives based on target
risk levels greater than 1 x 10
-6
(carcinogens) or greater than hazard quotient of 1
(noncarcinogens) only under Tier 3, as proposed by the Agency, or allow such determinations
under Tiers 1 and 2. They argue that the regulations do not comply with the Act because a
range of target risk levels is not available, and they advocate that Tier 1 and 2 specifically
allow for target risk levels greater than 1 x 10
-6
. Their arguments in support of such an
approach and the Agency’s response are summarized below at pages 52-56.
These concerns gave rise to a discussion about the risk assessment which must be
performed under Tier 3 to demonstrate a greater target risk level is protective of human health.
The Agency and a number of the commentators offered lists of the factors they believe must be
addressed in such a risk assessment. Ultimately, the Agency gleamed from those lists the four
factors it believes critical in such a risk assessment. Those factors are: 1) the presence of
sensitive populations; 2) the number of receptors potentially impacted; 3) the duration of risk
at the differing target levels; and 4) the characteristics of the chemicals of concern. See
Section 742.915(h).
The Board finds that the Agency’s proposal provides a balanced approach for determining
remediation objectives that are protective of human health. Allowing higher risk levels under Tiers
1 or 2, as proposed by some participants, could result in overall risk levels at sites with certain
multiple contaminants to fall outside the acceptable range specified in Section 58.5 of the Act. The
Board agrees with the Agency that any changes in risk levels must be supported by formal risk
assessment under Tier 3. The Board also agrees that Section 742.915 needs to be modified to list
the elements which must be addressed by such a risk assessment if the applicant is seeking to
modify the target risk level. Accordingly, subsection (h) as proposed by the Agency is included in
this Second Notice.
Pursuant to Section 58.5(d)(4) of the Act, an applicant can seek site-specific remediation
objectives which exceed the Tier 1 remediation objectives,
i.e.
, the Board’s groundwater quality
standards at Part 620, under Tier 3. To obtain such an exception, the Act requires two
demonstrations. First, the applicant must demonstrate that the exceedence of the groundwater
quality standard has been minimized and the beneficial use of the groundwater has been returned,
30
and that any threat to human health has also been minimized. These two statutory requirements are
incorporated verbatim into the rules at Section 742.900(c )(9). Since the right to exceed
groundwater quality standards, adopted by the Board as the level at which human health is
protected, is available only due to this statutory exception, it is most important that the
demonstration to obtain such a right comply with the these statutory requirements.
Subpart J: Institutional Controls
Institutional controls are defined under the proposed rules as “a legal mechanism for
imposing a restriction on land use.” The Agency testified that institutional controls are a
fundamental part of the proposal, and are the key to assuring long-term protection of human health,
while providing flexibility in developing practical, risk-based remediation objectives. (Exh.
3 at 1.)
The applicant must obtain an institutional control whenever the applicant seeks to take any of the
following measures, or any combination thereof: 1) restrict a property to industrial/commercial use;
2) establish remediation objectives based on a target cancer risk greater than 1 in 1,000,000; 3)
establish a target hazard quotient greater than 1 for a noncarcinogen under a Tier 3 analysis; 4) rely
on an engineered barrier; 5) set the point of human exposure at a location other than at the source;
or 6) exclude exposure pathways under Subpart C.
Pursuant to Subpart J, the following types of institutional controls are recognized under
these rules: 1) No Further Remediation Letters; 2) restrictive covenants, deed restrictions, and
negative easements; 3) ordinances adopted and administered by a unit of local government; and 4)
agreements between a property owner and a highway authority with respect to any contamination
remaining under highways. The requirements for each of these categories are set forth in a separate
section.
Whether an institutional control is transferable with the property was an issue raised at
hearing. The Agency and interested participants agreed that it should be transferable. During the
public comment period, the Board received several comments in support of transferability. The
Board examined the issue and concludes that an institutional control is transferred with the property.
Therefore, the Board adopts the following at Section 742.1000(d): “An institutional control is
transferred
with the property.” For further discussion of this issue, see pages
56-58,
supra
.
The requirements for a No Further Remediation Letter is set forth at Section 742.1005. As
originally proposed at First Notice, this section included detailed conditions concerning the
recording of No Further Remediation Letters, their effectiveness, and their voidance. However, in
its Errata Sheet No. 3, the Agency proposed deleting these provisions, and leaving only the
language in subsection (b) which states that “a request for approval of a No Further Remediation
Letter as an institutional control shall follow the requirements applicable to the remediation program
under which the remediation is performed.” The Board finds that the modification to Section
742.1005 in Errata Sheet No. 3 should be adopted. The TACO rules are intended to establish a
method for deriving corrective action objectives for remedial programs. Specific provisions
concerning the effectiveness and limitations on No Further Remediation Letters and other
instruments memorializing a no further remediation determination by the Agency are more
appropriately set forth in the specific programs pursuant to which the such a determination is made.
31
The requirements for restrictive covenants, deed restrictions, and negative easements are set
forth at Section 742.1010. At hearing, the Agency testified that it anticipates that these measures
will be used only in situations where a No Further Remediation Letter is not available, and that it is
not necessary to obtain restrictive covenants, deed restrictions, or negative easements which
duplicate conditions set forth in a No Further Remediation Letter that is appropriately recorded.
Restrictive covenants, deed restrictions, and negative easements approved by the Agency in
accordance with this Section must be appropriately recorded, together with the instrument
memorializing the Agency’s no further remediation determination,
e.g.
, a No Further Remediation
Letter.
Section 742.1015 sets forth the requirements for ordinances used as an institutional control.
The use of an ordinance as an institutional control is specifically limited to ordinances that
effectively prohibit the installation of potable water supply wells in order to meet the requirements
of Section 742.320(c) or 742.805(a)(3). Unless the Agency and the unit of local government have
entered into a Memorandum of Understanding (MOU), this section places the burden on the owner
or successor in interest for monitoring the local governments activities with respect to the
ordinance. If the ordinance is modified, or if a variance or other site-specific request is granted that
allows use of the groundwater at the site as a potable water supply, or if the terms of another
institutionally control at the site are violated, the use of the ordinance as an institutional control can
be voided.
In Errata Sheet No. 2, the Agency proposed that this Section be modified to provide that
ordinances which do not prevent the unit of local government from installing or using such wells
may still be relied upon as an institutional control, if the unit of local government enters into a
MOU with the Agency and the MOU satisfies certain requirements designed to assure that the local
government will protect the water supply from contamination left in place.
Section 742.1015 sets forth procedures for ordinances that ensures that neighboring
landowners are placed on notice relative to contamination that may have moved towards or
under their property. (Exh. 3 at 4.) In order to address concerns raised at hearings, the
Agency made changes to Section 742.1015 in Errata Sheet No. 2. IPC has expressed concerns
regarding those revisions. (PC 8 at 8.) IPC believes that the revisions are overly broad in
requiring a MOU in all instances where the ordinance does not prohibit the unit of local
government from installing new wells. In this regard, IPC notes that the revisions proposed
by the Agency would preclude the use of a vast majority of existing ordinances which do not
expressly prohibit the unit of local government from installing new wells, unless the
government took the additional step of entering into an MOU with the Agency. IPC provides
language changes that address its concerns.
The Agency clarified its position concerning the MOU in its additional comments. (PC
15 at 3-7.) The Agency notes that, from the standpoint of human health and safety, it is not
reasonable for the ordinance to allow public water supply systems to tap groundwater where
contamination above Tier 1 levels has been allowed to remain. However, the Agency contends
that the regulations will not prohibit all public uses of affected groundwater. The Agency
states that the proposed provisions resolve the conflicting principles by allowing the use of
ordinances that expressly do not prohibit the installation of a public water supply well by a unit
32
of local government so long as they enter into a MOU with the Agency. The Agency believes
that entering the MOU and abiding by the commitments contained therein will forewarn
communities of the existence of contamination plumes and may prevent costly mistakes in
siting, construction, and use of public potable water supply wells. (PC 15 at 7.)
The proposed requirements concerning the MOU at Section 742.1015(i) require the unit
of local government to make a commitment to: maintain a registry of all sites within its
boundaries which have received a No Further Remediation Letter and review the registry of
sites prior to siting potable water supply well; consider if groundwater contamination from the
sites on the registry may be present at potential well sites; and take appropriate protective
measures if wells are sited in the vicinity of such locations.
Given the potential human health risk and the cost of groundwater remediation and
installation of potable water supply wells, it makes sense to be forewarned about potential
problems concerning a groundwater source. Moreover, as noted by the Agency, most of the
existing ordinances were not enacted by considering environmental concerns. In this regard,
the proposed regulation provides an opportunity to a unit of local government to adopt an
ordinance based upon the consideration of environmental concerns. For these reasons, the
Board proposes to adopt the changes proposed at Section 742.1015 and sections cross-
referencing it at Sections 742.320(d) and 742.805(a)(3).
Finally, Sec
tion 742.1020 sets forth the requirements applicable to highway authority
agreements used as an institutional control. When contamination level of the groundwater exceed
the Tier 1 residential levels, the highway authority must agree to prohibit the use of groundwater
under the highway right-of-way as a potable water supply. When the contamination of the soil
under the highway right of way exceeds the Tier 1 residential level, the highway authority must
agree to limit access to soil contamination, and in the event access is allowed, human health and the
environment must be protected.
33
Subpart K: Engineered Barriers
An engineered barrier is defined in Section 742.200 as a barrier designed or verified using
engineering practices that limits exposure to or controls migration of the contaminants of concern.
Mr. King testified that, in addition to including man-made structures designed using engineering
practices, engineered barriers could include native or
in-situ
materials if their effectiveness is
verified using engineering practices. (Exh. 3 at 7) The use and maintenance of an engineered
barrier must be accompanied by an institutional control in accordance with Subpart J.
Furthermore, any no further remediation determination by the Agency based on the use of the
engineered barrier must be conditioned upon maintenance of the engineered barrier, and the
institutional control must address provisions for temporary breaches of the engineered barrier.
Failure to maintain an engineered barrier in accordance with the terms of the no further remediation
determination constitutes grounds for voidance of that determination.
Section 742.1105 sets forth the requirements for engineered barriers and limitations on their
use in achieving remediation objectives. It makes clear that natural attenuation, access controls and
point of use treatment do not fall within the definition of engineered barriers, and that engineered
barriers cannot be relied upon in determining compliance with Tier 1 remediation objectives.
Subsection (c) of this Section sets forth a list of engineered barriers accepted for each exposure
route. For the soil component of the groundwater ingestion exposure route, these include caps
constructed of clay, asphalt, or concrete, and permanent structures, such as buildings or highways.
For the soil ingestion and inhalation exposure routes, the acceptable engineered barriers include
clean soil at least three feet in depth, as well as caps and permanent structures. Finally, for the
groundwater component, the acceptable engineered barriers include slurry walls and hydraulic
control of groundwater. Subsection (d) of this Section makes it clear that the list of accepted
measures is not intended to be exhaustive and that other methods will be accepted by the Agency if
they are shown to be as effective as the listed options.
RESOLUTION OF MAJOR ISSUES
Subpart B: Definition of Residential Property and Compliance Demonstration for Two
Exposure Routes
Section 742.200: Definition of “Residential Property.” As explained above, the Board
modified the definition of “residential property” originally proposed by the Agency. That
decision was made after considering the arguments raised by Gardner Carton & Douglas
concerning the originally proposed definition, the revised definition proposed by Gardner
Carton & Douglas, the Agency’s disagreement with that revised definition, and the public
comments about this definition received by the Board in the Site Remediation Program
rulemaking, R97-11.
In this rulemaking, Gardner Carton & Douglas contends that the Agency’s proposed
definition needs to be modified to eliminate unnecessary confusion, and suggests the
following. (Exh. 15 at 3.)
34
“Residential Property” means any real property that is used for habitation by
individuals or where children have the opportunity for exposure to contaminants
through ingestion or inhalation at any educational facilities, or playgrounds where soil
ingestion or inhalation pathways for children are found to exist.
Gardner Carton & Douglas argues that it is critically important that this definition be
clear and not subject to varying interpretations since the definition of “residential property”
provides the basis for the imposition of differing cleanup standards. Further, Gardner Carton
& Douglas asserts that the revisions it proposes are intended only for the purpose of
clarification and are not intended to change the intent. (December 10, 1996 Transcript at page
53.)
The Agency objects to the revisions since the changes do not account for a complete
exposure pathway. (Exh. 20 at 1.) The Agency contends that whether the pathway is
complete is not clear under Gardner Carton & Douglas’ proposed revision, since the revision
deletes the language “..have the opportunity for exposure to contaminants.” Additionally, the
Agency states that Gardner Carton & Douglas’ revisions are limited to what is “found to exist”
at the time of the investigation and not what may occur in post-remediation uses. (Exh. 20 at
1.) Finally, the Agency notes that the Board upheld the Agency’s definition of “residential
property” in its First Notice opinion concerning the Site Remediation Program. (PC 10 at 4.)
(See R97-11 Opinion of February 6, 1997 at pages 13-14.)
As noted by the Agency, the Board did not accept the revisions suggested by Gardner
Carton & Douglas in its First Notice opinion concerning the Site Remediation Program. The
Board found the revisions inappropriate for the reasons stated by the Agency. (Id.) However,
in the First Notice opinion for the proposed Site Remediation Program, the Board expressed
concerns regarding two other aspect of the Agency’s proposed definition. First, the Board
questioned whether the Agency’s proposed definition reflects the statutory intent. Section 58.2
of the Act defines “residential property” as any “real property that is used for habitation by
individuals and other property uses defined by Board rules such as education, health care, child
care and related uses.” The Board observed that by equating “playgrounds” with “related
uses,” the Agency may have constructed “related uses” too narrowly. Additionally, the Board
also asked for clarification about the phrase “by ingestion or inhalation” in describing
exposure to children.
Thereafter, the Board received several comments concerning this definition in the R97-
11 rulemaking. After examining those comments and the definition closely, the Board
concluded in R97-11 that the Agency’s definitions required nine modifications. In sum, the
Board concluded therein that the term “playgrounds’ was too narrow, to encompass many
areas where children regularly lay, and substituted it with the term “outdoor recreational
areas”. The modifier “outdoor” precludes the term “recreational areas’ from encompassing
those recreational areas where there is little threat of exposure e.g. indoor recreational
facilities. For an expanded discussion on the modified definition adopted by the Board, see the
R97-11 Opinion for Second Notice, at pages 11-14 (April 17, 1997).
35
The definition adopted today by the Board in this rulemaking, as well as in the R97-11
rulemaking, reads:
“Residential Property” MEANS ANY REAL PROPOERTY THAT IS USED FOR
HABITATION BY INDIVIDUALS, or where children have an opportunity for
exposure to contaminants through soil ingestion or inhalation at an educational
facilities, health care facilities, child care facilities, or outdoor recreational areas.
Section 742.225: Compliance with Remediation Objectives. At Section 742.225(d), as
originally proposed by the Agency, detailed compositing and averaging requirements were set
forth for demonstrating compliance for the inhalation and soil ingestion exposure routes. At
hearing, Gardner Carton & Douglas stated that the proposed compliance requirements at
Section 742.225(d) were not consistent with the exposure route evaluation requirements set
forth in Sections 742.310 and 742.315, which specify pathway exclusion requirements for the
inhalation and soil ingestion exposure routes. (Exh. 15 at 4-5.) These requirements include a
criterion based on the depth of contamination. Specifically, Section 742.310(b) provides that
“the concentration of any contaminant of concern within ten feet of the land surface or any
man-made pathway shall not exceed the Tier 1 remediation objective under Subpart E for the
inhalation exposure route,” and Section 742.315(b) provides that “the concentration of any
contaminant of concern within three feet of the land surface shall not exceed the Tier 1
remediation objective under Subpart E for the ingestion of soil exposure route.” Alternatively,
both rules would allow the applicant to rely on an engineered barrier installed in accordance
with Subpart K. (Section 742.310(b)(2) and 742.315(b)(2).) Gardner Carton & Douglas
contends that the compliance requirements proposed at Section 742.225(d) do not incorporate
these depth criteria and asserts that such criteria should be incorporated into the compliance
requirements set forth in Section 742.225. (Exh. 15 at 5.)
In response to Gardner Carton & Douglas’ comments, the Agency proposed in Errata Sheet
No. 2 that this Section be modified to allow greater flexibility for the applicant in developing a
proposed sampling scheme. (January 15, 1997 Transcript at pages 103-110.) The Agency
proposed that the specific sampling protocols at Section 742.222(d) be deleted and that a new
provision be added that requires each applicant to submit a sampling plan for Agency approval
based upon a site-specific evaluation. The prohibition against compositing of VOC samples is
retained, as is the requirement that all samples be collected within the contaminated area. As a
result of the changes to this subsection, the Agency also proposed deleting Section 742.225(f),
because it originally provided for the use of an alternative method approved by the Agency, and
Section 742.225(d) now incorporates the same flexibility.
The Board believes that Gardner Carton & Douglas’ testimony raised valid concerns
regarding the proposed requirements at Section 742.225(d). Based on the Agency’s initial
testimony, if the contamination extends below one foot from the surface, then Section 742.225(d)
would require soil sampling below one foot from the surface to show compliance for the inhalation
and ingestion exposure routes. (December 10, 1996 Transcript at pages 208-218.) However, the
Agency’s proposed changes to Section 742.225(d) provide greater flexibility for the applicant to
develop an appropriate sampling scheme for compositing or averaging soil samples when
36
determining compliance with objectives for these exposure routes. Even though the changes in
Errata Sheet No.2 do not incorporate the depth criteria suggested by Gardner Carton & Douglas,
they address Gardner Carton & Douglas’ concerns by allowing the applicant to submit a sampling
plan based on site-specific conditions. The Board therefore accepts the Agency’s proposed changes
to Section 742.225(d) and finds no need for the additional changes suggested by Gardner Carton &
Douglas. Furthermore, as a result of these amendments, the Board adopts the Agency’s proposed
deletion of Section 742.225(f).
Subpart C: Objections to General Criteria and Specific Criteria for Pathway Exclusions
Section 742.305: Objections to Point of Human Exposure as Compliance Point and
Prohibition of Source Material Exhibiting Hazardous Characteristics. Jenner & Block
contends that the proposed provisions, which are linked to stringent cleanup levels for risk of
migration to groundwater in Tier 1 and include the requirement of an institutional control if
any pathway is excluded, will create a form of environmental zoning. Jenner & Block
suggested two changes to the general criteria for exclusion of pathways. The first concerns the
location of the point of human exposure and the second concerns the applicability of the
general exclusion criteria to the migration to groundwater pathway.
Concerning the location of the point of human exposure, Jenner & Block states that the
proposed rules are based on the assumption that the point of human exposure is the source of
the material and that using any other point of exposure would require a deed restriction. (Exh.
18 at 18.) Jenner & Block states that Agency’s proposal under Subpart C assumes that there is
someone with a groundwater well, drinking water directly from the source of contamination,
and that individuals are at the source ingesting and inhaling vapors from the contamination. In
this regard, Jenner & Block notes that an owner/operator under the Underground Storage Tank
program may move the point of exposure up to 200 feet because that is a statutory point of
compliance. As a result, Jenner & Block suggests that the Board set a point of compliance at
the closer of the downgradient property line boundary or 200 feet from the source.
In response, the Agency urges the Board to adopt the requirements for pathway
exclusions as proposed, including the proposed limits on contaminant concentration. The
Agency notes that the proposed regulations under Tier 3 allow for pathway exclusion without
any limits on contaminant concentrations. (See Section 742.300)
As noted by the Agency, the basic premise of pathway exclusion is effective control of
the source, coupled with site conditions and an appropriate institutional control that effectively
prohibits human exposure through a given pathway. The underlying assumption that the point
of human exposure is at the source of the material is justified since the exclusion of a pathway
under Section 742.Subpart C is intended to demonstrate that the site does not pose a threat to
human health through that pathway. If the point of exposure is moved away from the source
without engineered barriers and institutional controls, then the potential risk of exposure would
still exist. Additionally, for those sites that do not qualify for pathway exclusion under
Subpart C, the applicant may pursue pathway exclusion under Tier 3. (PC 10 at 6; Exh. 20 at
3.) Finally, the compliance point is not defined under the TACO regulations and it is more
37
appropriately addressed under the regulations pertaining to the specific remediation programs.
The Board therefore does not make any changes concerning the compliance point.
Concerning its second issue, Jenner & Block argues that the general limits on pathway
exclusions at Section 742.305(c) through (e), which require the applicant to insure that the
contaminated soil remaining in place does not exhibit the hazardous characteristics of
reactivity, corrosivity, or toxicity, do not relate to the risk of migration to groundwater
pathway. Jenner & Block contends that these proposed limits potentially relate to the
ingestion and inhalation pathways. Moreover, Jenner & Block asserts that these restrictions
act as additional cleanup standards that every site must meet if it wishes to exclude any
pathway, even one which is not affected by these three limitations. (Exh. 18 at 20.) Jenner
& Block maintains that the limits on exclusions are inappropriately placed and that they should
be proposed as independent remediation objectives.
The Agency urges that the Board not make any changes to Section 742.305. The
Agency notes that pathway exclusion allows source material to be left in place if it is
determined that the particular exposure route is not a concern. Therefore, the Agency
believes that it is critical to place limits on how much contamination may be left behind under
Subpart C. (PC 10 at 5.) The Agency did admit that should the source material fail these
three criteria, there might not necessarily be an increased risk to groundwater. However, the
Agency reiterated that if a source material fails these criteria, the material would be
aggressively reactive and toxic. Furthermore, the Agency states that, if the limits are
exceeded, it may be impossible to model the behavior of the contaminants, and the
contaminants may pose unacceptable health risks including: serious dermal effects from even
brief contact with contamination; absorption of contaminants through the skin into the blood
stream; immediate danger to human health and life or organ damage (skin, lungs, kidneys)
from exposure to high concentrations; immediate danger to skin and eyes from exposure to
extreme pH ranges; and fires or explosions resulting from seepage of free product into
basements, parking garages, or utility trenches. (PC 10 at 5.)
In addition, the Agency states that there is always a risk for unintentional or accidental
exposure to contamination left in place should the engineered barriers and institutional
controls fail, or should responsible persons not fulfill their obligations to perform ongoing
maintenance. (Exh. 20 at 2.) The Agency contends that the limits proposed at Section
742.305 provide a “ceiling” or “control” mechanism to limit the level of exposure from high
contaminant concentrations.
The Board does not agree with Jenner & Block that these three criteria are not
applicable to the migration to groundwater pathway. Soils with a very low pH promote
mobility of metals, which in turn may result in an increased threat of groundwater
contamination
.
Additionally, the levels of the inorganic chemicals or their salts as measured
using the TCLP test have a direct bearing on the migration to groundwater pathway since the
regulations, for a number of inorganic chemicals, require the TCLP results to be compared
with the Tier 1 remediation objectives for the migration to groundwater pathway in Part
742.Appendix B, Tables A and B. The Board therefore finds it reasonable to require the above
38
limits to be generally applicable to the evaluation of all exposure routes. However, as the
Agency clarified, site-specific information will dictate how the Section 742.305 limits are
addressed. (December 10, 1996 Transcript at pages 230-232.) Actual sampling may not be
required if it is possible to address one or more of the limits on the basis of site characteristics.
The Board therefore declines the suggestions made by Jenner & Block and adopts for second
notice the general pathway exclusions requirements as proposed by the Agency at Section
742.305.
Sections 742.310, 742.315 and 742.320: Specific Requirements for Excluding
Pathways. Jenner & Block raises three concerns about the specific criteria applicable to the
pathway exclusion process. These issues concern: (1) the exceptions from the depth limitation
requirements at Sections 742.310(b)(1) and 742.315(b)(1); (2) the requirements at Sections
742.310(b) and 742.315(b) for an institutional control in all instances where the contaminant
levels exceed the allowable levels for inhalation or ingestion routes; and (3) the requirement at
Section 742.320(d) that an ordinance be adopted by a unit of local government within 2500
feet of the source restricting use of groundwater.
First, Jenner & Block recommends that the regulations allow exceptions from the limit
for contamination within the first three feet of the surface for the risk of ingestion pathway,
and the first ten feet of the surface for the inhalation exposure route. In this regard, Jenner &
Block asks that the regulations allow evaluation of deeper contamination within the 200-foot
radius of the source. (Exh. 18 at 19.) The Agency did not specifically address Jenner &
Block’s concerns regarding depth limitations. However, the Agency’s statement concerning
Section 742.305 that Tier 3 is available to those sites where removal of all source
contamination and free product is not achievable appears to touch upon this issue. (Exh. 20 at
3.)
The limitations that Jenner & Block refers to are set forth at Sections 742.310(b)(1) and
742.315(b)(1). For the inhalation exposure route, Section 742.310(b)(1) requires that the
concentration of any contaminant of concern within 10 feet of land surface or any man-made
pathway not to exceed the applicable Tier 1 remediation objectives. A similar requirement for
the soil ingestion exposure route is set forth at Section 742.315(b)(1), with a depth limitation
of 3 feet. If an applicant cannot show compliance within these depths, the applicant can seek to
use an engineered barrier to exclude a pathway.
The depth criterion for the inhalation exposure route is drawn from the RBCA
guidelines. The 10-foot thick layer of soil is intended to provide sufficient distance for
attenuation of vapors to concentrations below levels of concern. (Exh. 13 at 9.) The depth
limitation concerning ingestion is also drawn from the RBCA guidelines. The 3-foot soil
thickness provides sufficient protection against contact and ingestion by people and allows for
some mixing and disturbance of shallow soils over time. (Exh. 13 at 8.) In effect, the depth
criteria under Subpart C are intended to protect human health.
According to the testimony given by the SRAC, Subpart C is intended to provide
pathway exclusion procedures which are preliminary to any tier analysis. Therefore, the
39
pathway exclusion process is necessarily prescriptive in order to ensure that a qualifying site
does not present risk to a receptor. (Exh.
12
at 7.). The Board agrees. The requirements are
intended to ensure that, for a given pathway, a site which meets the applicable requirements
does not pose a threat to human health. The exception proposed by Jenner & Block from the
requirements under Subpart C would be contrary to this purpose and the safeguards the depth
limitations provide. As noted by the Agency in regards to Section 742.305, should an
applicant believe that such an exception is valid on a site specific basis, then the exception and
its impact to human health is best evaluated under Tier 3. Section 742.300 provides for that
type of analysis in lieu of the pathway exclusion process provided under Subpart C. For these
reasons, the Board will not adopt Jenner & Block’s recommendation to allow exceptions from
the depth limitations of Section 742.310(b) and 742.315(b).
Next, Jenner & Block recommends that the institutional control provision at Sections
742.310 and 742.315 be modified. Specifically, Jenner & Block suggests that the Board delete
the requirements at Sections 742.310(b) and 742.315(b) that require an institutional control in
all instances where the contaminant levels exceed the allowable levels for inhalation or
ingestion routes. Jenner & Block states that there would be little practical reason to require an
institutional control for the inhalation route when contamination is located deeper than 10 feet
from the surface or for ingestion route when contamination is located deeper than 3 feet.
(Exh. 18 at 20-21.) Jenner & Block argues that the likely risk posed by deeper soils is related
to construction workers and that such risks are addressed by Occupational Safety & Health
Administration restrictions. (Exh. 18 at 21.)
In response, the Agency states that it does not understand Jenner & Block’s concern.
The Agency believes that the institutional control will provide future owners the information
necessary to correctly manage the remaining contamination, and unless the necessary land use
restriction, management, and access requirements are effectively imposed, the traditional
process of remediating sites to meet the most restrictive use requirements would be required.
(Exh. 20 at 7.)
We agree with the Agency that Jenner & Block’s concern about the institutional
controls is not clear. The pathway exclusion procedures of Subpart C are based on effective
source control and an institutional control which, together, effectively prohibit human
exposure through a given pathway. Absent an institutional control, it is not clear how the
management requirements pertaining to remaining contamination would be implemented by
future owners. This is especially critical since contamination remains in place. The Board
believes that Jenner & Block has not justified its request to delete the institutional control
requirements. Accordingly, the institutional control requirements at Sections 742.310 and
742.315 are adopted for second notice.
Finally, Jenner & Block expressed concern about the requirement at Section 742.320(d)
that an ordinance be in place,
i.e.
, adopted by a unit of local government to prohibit the
installation or use of potable water supply wells within 2500 feet of the source of the release.
Jenner & Block states that this requirement is overly conservative since it includes
communities located both upgradient and downgradient from the source. (Exh. 18 at 21.)
40
Jenner & Block proposes that the ordinance requirement be applied only to communities that
are downgradient of the source with respect to the direction of groundwater flow. In this
regard, Jenner & Block notes that the Agency’s position is that the rule should also apply to
upgradient because the direction of groundwater flow may change. (Exh. 18 at 22.)
At first, Jenner & Block’s downgradient argument appears valid, since a contaminant
plume, if present, generally moves along the direction of groundwater flow. However, to
require ordinances only in communities located downgradient of the source, a detailed site
hydrogeological characterization would be needed to ensure protection of the upgradient
groundwater resource. Site characterization requirements are not addressed in TACO;
instead, site characterization requirements are program specific. Therefore there is no
assurance that the site characterization would provide sufficient detail to provide a clear
picture of the site hydrogeological conditions. Considering that contamination may remain in
place under Subpart C and that there is always a potential for changes in groundwater flow,
the proposed requirement at Section 742.320(d) ensures that groundwater in the vicinity of the
source will be excluded from potable uses. The Board therefore will not limit the
applicability of this subsection to downgradient communities.
Subpart D: Three Issues Concerning Use and Determination of Area Background
Three issues were raised regarding area background at hearing. The three issues are:
1) exclusion of a contaminant of concern based on area background; 2) substitution of area
background for Tier 1 residential objectives if the naturally occurring background level of a
contaminant of concern is greater than Tier 1 residential level; and 3) the propriety of
changing Appendix A, Table G to use the 50
th
percentile values versus the 90
th
percentile
values from the Agency’s area background database.
Section 742.415: Use of Area Background to Exclude a Contaminant. The first issue,
excluding a contaminant of concern based on area background, was raised because in Errata
Sheet No.2, the Agency deleted the originally proposed rule which allowed a contaminant of
concern present as a result of area background to be excluded from further consideration. The
Illinois Steel Group (ISG) disagreed with such a change, arguing that the Agency was
interpreting the Act too narrowly. ISG contends that remediation objectives and cleaning up
any contaminant which meets the statutory definition of area background is required only in
the case of the two exceptions found in the Act: 1) at residential property, or 2) when the
Agency makes a written finding that the regulated substance may cause an acute threat to
human health. ISG wanted the new language in Errata Sheet No. 2 withdrawn and the original
language returned. (PC 7 at 4.)
The first issue is resolved because the Agency has agreed that contaminants can be
excluded if they are equal to or below area background levels subject to the two statutory
limitations set from further consideration at Section 742.415. Section 742.415(b)(1) allows
the exclusion of a contaminant of concern based upon the area background subject to the two
statutory limitations found in Section 58.5 of the Act. Area background concentrations cannot
be used to exclude a contaminant from further concern if (1) the Agency has made a finding
41
that the area background level poses an acute threat to human health or the environment, or (2)
the area background level exceeds the residential remedial objective at residential property.
Section 742.415: Use of Area Background Concentration as Remediation Objective.
The second issue was raised by Ms. Linda Huff who testified on behalf of the Site
Remediation Coalition, represented by Gardner Carton & Douglas. In her pre-filed testimony,
Ms.Huff stated that there are sites in Illinois where the area background of naturally occurring
chemicals are greater than the Tier 1 residential remediation objectives listed in Appendix B,
Table A. (Exh.15 at 11.) As an example she cited arsenic which has a Tier 1 value of 0.4
mg/kg and the area background level is 5.2 mg/kg for counties outside the metropolitan
statistical areas and 7.2 mg/kg for counties inside the statistical areas. She believed that the
rules as modified would require all sites that have an area background greater than the Tier 1
residential value would have to be limited to industrial/commercial uses. She also questioned
how property currently being used as residential would be handled if this proposal is not
changed.
The proposed regulations now allow area background levels to replace Tier 1
remediation objectives which are less than area background levels for sites that are specified as
something other than residential. In essence, Garner Carton & Douglas wants the Agency to
allow area background levels to replace Tier 1 residential levels.
Regarding the use of area background concentrations in place of Tier 1 remediation
objectives, the Agency states that the entire premise upon which its position is drawn stems
from the statutory definition of “area background
7
.” (PC. 15 at 6-7.) The Agency concludes
that even though area background is not limited to pristine conditions, contaminants of concern
resulting solely from one release cannot be considered as background for another release,
whether on-site or off-site. With regards to the limitation that land use should be limited to
industrial/commercial sites where the area background levels are greater than the Tier 1 value,
the Agency notes that the requirement is statutory. In order to clarify the proposed intent, the
Agency has proposed, in its final comments, the addition of statutory language at Section
742.415(d) that prohibits the conversion of property’s land use to residential land use if
concentrations of contaminants of concern at the site exceeds the residential remediation
objectives. The Agency also stated in its rebuttal that studies have established carcinogenic
effects from naturally occurring levels of arsenic. Consequently, it would not allow the area
background level to replace any Tier 1 residential remediation objective. The Agency cited
Section 58.5(b)(2) in support of belief that background area levels cannot be substituted for
residential values even if the substance was naturally occurring as urged by Gardner Carton &
Douglas.
The Board agrees with the Agency that the Act prohibits background levels being
substituted for residential levels but with one caveat. Section 58.5(b)(2) of the Act prohibits
property being converted to residential property unless the residential remediation objective
adopted by the Board is first achieved, but provides that property may be converted to
residential use if an alternative risk-based remediation objective is achieved. Therefore, the
7
“Area Background” is defined as the concentrations of regulated substances that are
consistently present in the environment in the vicinity of a site that are the result of natural
conditions or human activities, and not the result solely of releases at the site.
42
Board will adopt the language proposed by the Agency at Section 742.415(d) taken from
Section 58.5(b)(2) of the Act. Finally, if the land use is restricted to something other than
residential, an institutional control is required by the last sentence in Section 742.415(d).
Section 742.405: Choice of 50
th
Percentile Values for Statewide Background Levels.
The third issue was raised in the second set of hearings because the Agency changed its
original proposal. Initially a range of values was proposed based on the 90th percentile from
the Agency’s database. When determining the statewide area background. In Errata Sheet
No. 2, the Agency changed its range to the 50
th
percentile because it does not believe that its
database is sufficiently reliable for the values to be based on the 90
th
percentile. Gardner
Carton & Douglas questioned the Agency’s decision to use the 50
th
percentile values in
Appendix A, Table G instead of the range that was initially proposed. Table G in Appendix A
contains the concentration of inorganic chemicals in background soils. This change was made
in the Agency’s Errata Sheet 2. Gardner Carton & Douglas contends that the Agency did no
analysis on the concentration distribution of area background, and cites several other states
which use the 90
th
percentile for their area background.
The Agency responded within its rebuttal that using a range of values from the database
is not dependable enough to replace any remediation objectives because: 1) of the
anthropogenic effects on some samples; 2) “the data set is not a product of a scientifically
designed and statistically valid survey;” 3) the samples came from numerous sites so there may
be differing levels of quality assurance/quality control; and 4) “most likely does not contain a
uniform degree of diligence.” (Exh. 20
at 4.) Therefore, the Agency chose to use the 50
th
percentile. In the Agency’s additional comments, it further addresses issues brought up by
Gardner Carton & Douglas on this topic. (PC 15 at 11.) In response to Gardner Carton &
Douglas’ comments, the Agency again disagrees. The Agency reiterates that the inorganic
background database is deficient in so many ways that it should not be considered reliable for
establishing area background based on 90
th
percentile. (PC 15 at 17.)
Gardner Carton & Douglas cites a Massachusetts document about their background soil
concentrations. The Agency states that within that document, the authors state that their
samples mostly came from rural and suburban locations and that they have some concerns
about elevated concentrations being considered as background. Therefore the Agency believes
that using the median from its database is preferable to the 90
th
percentile because of the urban
samples and other deficiencies. Finally, the Agency states that it would prefer Section
742.405(b)(1) and Appendix A, Table G be deleted and that site-specific information be the
only method for determining area background concentrations if the Board chooses not to use
the 50
th
percentile.
We are persuaded by the Agency’s arguments that the database is not sufficiently
reliable for the statewide area background level to be based upon a maximum value in the
range versus the median value. The Board agrees with the Agency to use the 50
th
percentile
instead the 90
th
percentile.
Subpart E: Two Alternatives for Setting Remediation Objectives for Inorganics
43
There are two alternatives for setting soil remediation objectives for the soil component
of the groundwater exposure route. The first alternative is based upon the TCLP test (Method
1311). The Board modified this alternative to allow use of the SPLP test (Method 1312) in
lieu of the TCLP test. The choice is the applicant’s. The second alternative for establishing
inorganic soil remediation objectives is based upon the total amount of contaminant in the soil
sample instead of either the TCLP or SPLP test. These remediation objectives are pH specific
and the appropriate soil remediation objective for Class I and Class II groundwater is to be
selected from Appendix B, Tables C and D, respectively. This second alternative cannot be
used if the soil pH is outside the range of 4.5 to 8.0. Based upon the following discussion, the
Board decided to allow the use of the SPLP test, and to limit the use of the second alternative
only to sites with soils having a pH within the 4.5 to 8.0 range only.
Section 742.510(a)(4): Use of the SPLP Test. The Agency supports its choice of
TCLP for three main reasons. First, the TCLP test is widely available and used routinely.
Second, the pH of the extract solution is appropriate for expected acid rain pH levels in
Illinois. Third, the extraction solution has enough buffering capacity to maintain its acidity
during the 18 hour static test. (PC 10 at 7.) The Agency states that the TCLP and the SPLP,
the alternative procedure proposed by Jenner & Block, are very similar in nature. However,
the Agency prefers the TCLP because the extraction solution used in the test is better buffered
to preclude a dramatic pH change and is sufficiently low that the static extraction will not
occur at unrealistically high pH levels after it is attenuated by the alkalinity of the soil at the
start of the test. (PC 10 at 10.) The Agency’s testimony also indicates that it decided to
propose this approach since the Board had previously upheld this procedure in the original
underground storage tank regulation, R94-2(A). (Exh. 5 at 20.)
Jenner & Block testified that the TCLP test is designed to mimic the highly acidic
conditions that occur in a municipal sanitary landfill. Further, Jenner & Block maintains that
the test was developed to assess whether wastes could be safely placed in a municipal landfill
and co-mingled with typical municipal waste streams in a highly acidic environment. Jenner &
Block also asserts that TCLP extraction solution is far more acidic than typical acid rain, and
points out that a contaminated site is exposed to rain water and not landfill leachate and
therefore a test that best mimics actual conditions at a contaminated site should be adopted.
(Exh. 18 at 6.)
Consequently, Jenner & Block recommends that the Board adopt SPLP, the test that
USEPA promulgated for determining compliance with cleanup objectives. Further, Jenner &
Block asserts that the USEPA rejects the use of TCLP test for risk assessment at any site other
than a municipal landfill. (Id.) For these reasons, Jenner & Block urges the Board adopt the
SPLP test which assumes that rain water, not laboratory grade acid falls from the sky, as a
more appropriate testing method for testing methods for metals. (Exh. 18 at 7.)
The TCLP test is generally used to determine if a waste is hazardous or to characterize
a waste to determine proper disposal. The TCLP procedure assesses risk to groundwater when
potentially hazardous toxic characteristic waste is co-disposed with solid waste in sanitary
44
landfills. The Agency proposes to use the TCLP test to assess whether certain metals in
contaminated soils meet the Tier 1 remediation objectives. The TCLP test and SPLP test are
essentially similar, differing only in the nature of the extraction fluid employed in the test.
The TCLP uses a more acidic extraction fluid than the SPLP, since TCLP is attempting to
mimic acidic conditions in a municipal landfill. Regarding this, the USEPA technical
assistance document for TCLP notes that:
When determining whether to use the TCLP for risk assessment it
is important to remember that the TCLP simulates worst case
management of hazardous waste in a landfill. Much caution must
be used before the TCLP data are used in risk assessment because
the TCLP conditions rarely reflect actual site conditions. EPA’s
Science Advisory Board Report Outlines many limitation of using
the TCLP for risk assessment at industrial sites. The [USEPA’s
Science Advisory] Board recommends developing leachate tests
which are appropriate to site condition.
(PC 3 at 2-9.)
When the Board adopted the use of the TCLP procedure in the original underground
storage tank rulemaking, R94-2 (A), it stated that the use of this method in the context of the
site remediation must be evaluated further. (Second Notice Opinion, R94-2(A)(August 11,
1994)
at 26). Based on the discussion above, the Board will allow the SPLP test as an
acceptable alternative to the TCLP test. The SPLP (Method 1312) is a USEPA promulgated
method and it is essentially similar to the TCLP (Method 1311). The USEPA technical
support document identifies the limitations involved in using the TCLP. According to it, the
TCLP is designed to mimic the conditions within a sanitary landfill where low pH conditions
exist as a result of anaerobic decomposition of wastes. On the other hand the SPLP is
intended to mimic the pH of rain water that percolates through a contaminated site and thus,
leaching the inorganic metals from the soil. The SPLP method appears well suited for use in
risk-based analysis, and since it is also a USEPA promulgated method, its availability and cost
should be comparable to that of the TCLP. To provide for this alternative, language is added
at Section 742.510(a)(4) of the rules proposed for Second Notice. This change also serves to
clarify that TCLP method is an acceptable method for establishing soil remediation objectives
for migration to groundwater. See Section 742.510(a)(4).
Section 742.510(a)(5): Soil Remediation Objectives Limited to pH Range. The Agency
and Gardner Carton & Douglas disagree about the range of the pH values limiting the use of
the second alternative to establishing soil objectives for the groundwater ingestion pathway.
The Agency states that the pH range of 4.5 to 8.0 is supported by the SSL. The Agency states
that it “does not believe that it is scientifically appropriate to extrapolate beyond the data that
was set forth in the USEPA SSL document because there can be dramatic changes over a
narrow pH range.” In response to Gardner Carton & Douglas’ comment, the Agency
provided justification based on the USDA soil database. Based on the USDA database, the
Agency further states that only a small proportion of sites (5%) would fall outside the range
45
already covered by Section 742.510(a)(5). The Agency believes that it is not burdensome to
defer those sites to a Tier 3 analysis. (Exh. 20 at 9.)
Gardner Carton & Douglas believes that the information upon which the Agency is
relying does not address urban areas. Gardner Carton & Douglas notes that the Agency’s
justification for considering the proposed pH range of 4.5 to 8.0 to be appropriate is based on
the characterization of shallow agricultural soil. Gardner Carton & Douglas further notes that
the acreage of the State is about 35.5 million acres, while the Agency’s soil survey data covers
34.04 million acres. Gardner Carton & Douglas infers that there are over one million acres
not represented in the Agency’s data. Gardner Carton & Douglas asserts that the remediation
experience in the urban locations suggests that pH conditions in urban soils routinely exist
above 8.0. Gardner Carton & Douglas also points out that the soil survey of DuPage and parts
of Cook County show pH range up to 8.4. Gardner Carton & Douglas states that its
consultant, Huff and Huff, Inc., has listed seven projects that it conducted where soil pH that
ranges over 8.0 was encountered. Gardner Carton & Douglas provided an extensive
discussion to conclude that at higher pH (between 8 and 11), metals such as copper, nickel and
cadmium precipitate out of solution and are therefore less mobile in the soil. For these
seasons, Gardner Carton & Douglas believes that the pH range should be expanded to include
higher pH levels. (PC 9 at 21-24)
We agree with the Agency that the SSL data supports the proposed pH range of 4.5 to
8.0. We note that the USEPA guidance documents do not address ranges for soils with pH
greater than 8.0. The Agency’s position indicates that the proposed rule would cover the 95%
of the sites and remaining 5% could develop remediation objectives under Tier 3. Developing
site specific remediation levels under Tier 3 at those sites where the soils have pH value of
greater than 8.0 seems at an appropriate course of action. We are not persuaded by Gardner
Carton & Douglas’ arguments. Gardner Carton & Douglas tries to differentiate between urban
soils and agricultural soils. It assumes that over one million acres not covered by the Agency’s
data are all urban areas. Gardner Carton & Douglas appears to conclude that the urban soils
have pH over 8.0, yet, it has not provided any scientific literature in support of this
hypothesis. The only fact supported by the record is that pH increases with increasing depth
of soil. (PC 9, Attachment B.) Ms. Huff cites seven instances where the pH range was over
8.0; however, she does not identify the total number of sites from which the seven sites were
chosen. Without such information, it is impossible to determine the relative occurrence of pH
greater than 8.0.
To conclude, the pH range of 4.5 to 8.0 is well supported by the record. Therefore,
this limitation upon the use of Appendix B, Tables C and D shall remain. We note that for
sites that have pH value greater than 8.0, site-specific remediation objectives may be
established under Tier 3.
46
Sections 742.505(b)(3) and 742. 610: Cumulative Effect of Similar-Acting
Chemicals.
8
The Agency’s initial proposal required the consideration of the noncarcinogenic
effect of mixtures of similar-acting chemicals under the Tier 2 evaluation. The Agency relied
on the SSL to support the proposed requirements pertaining to mixtures. In this regard, the
Agency notes that the SSL recommends that cumulative effect of chemicals that affect the
same target organs must be addressed, since the objectives are calculated to pose no more than
a 1 in 1,000,000 risk or hazard quotient of 1 for individual carcinogen or noncarcinogen,
respectively
9
. (Exh. 5 at 28-29.) The Agency states that if there are multiple chemicals at a
site that affect the same target organ, then the potential exists to exceed an acceptable exposure
for that target organ.
For carcinogens, the Agency states that the proposal affords a “built-in” protection.
Even if there are ten carcinogens at a site that affect the same target organ, the cumulative
cancer risk for a particular target organ if each chemical is present at its Tier 1 or Tier 2
remediation objective is 1 in 100,000, or midway within the acceptable risk range
10
of 1 in
10,000 to 1 in 1,000,000. (Exh. 5 at 29.)
However for noncarcinogens, the Agency states that there is no “built-in” safeguard for
cumulative risks, since there is no corresponding range of acceptable hazard quotients.
Therefore, if even two chemicals affecting the same target organ are present at their
remediation objective, the cumulative hazard quotient could be 2.0. (Exh. 5 at 29.) In light
of this, the Agency’s initial proposal addressed only noncarcinogenic effects.
As initially proposed, the requirements of Section 742.610 would have applied only
under Tier 2 evaluation when determining soil and groundwater remediation objectives for
noncarcinogenic chemicals. Regarding Tier 1, the Agency testified that even though there is
no built in safeguards for noncarcinogens, the consideration of the effects of similar-acting
chemicals is not a concern due to the built in conservatism of the Tier 1 remediation
objectives. (Exh. 5 at 29.) However, in its final comments, the Agency clarified that the
consideration of the effect of mixture of similar-acting chemicals is unnecessary only with
regards to Tier 1 soil remediation objectives. (PC 10 at 11.)
Accordingly, the Agency proposed the addition of a new provision at Section
742.505(b)(3) that requires the evaluation of the effect of similar-acting chemicals in
determining the Tier 1 groundwater remediation objectives. (PC 10 at 11.) This provision,
which applies only to Class I groundwater remediation, requires the consideration of the both
carcinogenic and noncarcinogenic
effects of similar-acting chemicals in determining Tier 1
groundwater remediation objectives. The Agency states that since it has taken a position that
Part 742 should rely on the State’s groundwater quality standards as closely as possible, the
8
As adopted for Second Notice, this section has been modified and now appears at Section
742.720 and 742.805(c).
9
Tier 1 values and Tier 2 equations are based upon a one-in-a-million individual excess cancer
risk for carcinogens and a hazard quotient of one for non-carcinogens. (Exh. 4 at 12 & 21.)
10
The acceptable risk range is set forth at Section 58.5 of the Act.
47
additional provision accounts for Class I groundwater. (PC 10 at 11.) However, the Agency
does not provide any rational for requiring the evaluation of carcinogenic effect of mixture of
similar-acting carcinogenic chemicals in determining groundwater remediation objectives.
The changes proposed in Errata Sheet No. 3 also clarify the scope of the proposed
requirements for mixture of similar-acting chemicals under Tier 2. These changes include
moving Section 742.610 requirements to Section 742.720 and the addition of a separate
provision under Section 742.805 to address remediation objectives for soil and groundwater,
respectively. So, in effect, the changes proposed by the Agency require the effect of mixtures
of similar-acting chemicals to be considered as follows:
Tier
Soil RO
*
Groundwater RO
**
1
NA
Yes
2
Yes
Yes
* - Noncarcinogenic effect
** - Carcinogenic and noncarcinogenic effect only for Class 1 groundwater
The SRAC, IERG, ISG and IPC strongly urge the Board not to accept the proposed
changes. IERG believes that the new addition at Section 742.505(b)(3) makes Tier 1 not “user
friendly.” (PC 4.) The SRAC states that it is unnecessary to address mixtures of similar-
acting chemicals for carcinogens and noncarcinogens in groundwater under Tier 1 and Tier 2.
In this regard, SRAC contends that Tier 1 remediation objectives and Tier 2 formulae have
safety factors built into them which will necessarily result in very conservative remediation
objectives. The SRAC believes that the conservative nature of the remediation objectives and
the manner in which they are used adequately assure equivalent protection should mixtures of
similar-acting chemicals be present within a given exposure pathway. (PC 21 at 6.)
IERG states that the complexity of site specific conditions and the need to search
through the appendices makes Tier 1 no longer straight forward or user friendly as it was
designed to be. ISG and IPC also state that Tier 1 tables are intended to be used as look-up
tables to determine appropriate remedial values. (PC 7 & 8.) They contend that with the new
reference to Section 620.615 that is no longer possible. Both ISG and IPC state that the
Agency never brought this subject up within the hearings, and they note that any discussions
the Agency had with the SRAC is not on the record. Additionally, ISG and IPC state that
Section 620.615 do not directly specify how the remediation objectives are to be determined.
(PC 7 & 8.)
In its additional comments, IPC gives an example of how the proposed new provision
may have a significant impact on UST sites. (PC 20.) At UST sites two of the BETX
compounds, ethylbenzene and toluene, target the liver and the kidney. Under the proposed
changes, all UST sites with groundwater issues would have to be evaluated using the new
equation. This may render Tier 1 to be unavailable for most UST sites.
48
As noted above, the main concern regarding the proposed changes relates to the
evaluation of the effect of mixtures of similar-acting chemicals under Tier 1. If the Board
accepts the proposed changes, then the process of determining Tier 1 groundwater remediation
objectives would require an additional step beyond the Tier 1 look-up tables if: the
contaminants of concern include mixtures of two or more similar-acting chemicals listed in
Appendix A, Table E and Table F; and Class I groundwater is contaminated by such
chemicals.
The additional step involves the correction of the remediation objective for each
chemical in the mixture to account for the cumulative effect. The Agency has provided two
optional procedures for performing this additional analysis under Section 742.505(b)(3)(C)
(which is now at Section 742.505(b)(3).) These procedures, which are essentially the same as
those that were initially proposed under Tier 2 evaluation, are described below by considering
a hypothetical site contaminated with BETX.
It is assumed that BETX are present at concentrations equal to their respective Tier 1
remediation objectives, namely, Benzene - 0.005 mg/L, Ethylbenzene - 0.7 mg/L, Toluene -
1.0 mg/L, Xylenes - 10 mg/L. According to Appendix A, Table E, Ethylbenzene and
Toluene, which are noncarcinogens, affect the same target organs,
i.e.
kidney and liver.
Therefore, their remediation objectives must be corrected for cumulative effects. The first
option at Section 742.505(b)(3) requires the calculation of weighted average as follows:
W
x
CUO
x
CUO
x
CUO
W
W
AVE
x
x
a
x
AVE
AVE
a
=
+
+
+
=
+
=
1
2
1
2
10
10
0 7
0 7
2
.....
.
.
.
.
where,
x
1
, x
2
, .. = concentration of contaminants
W
ave
= weighted average
CUO
x1
, CUOx
x2
, ..= Tier 1 remediation objective
According to Section 742.505(b)(3), remediation objectives are met if W
ave
is less than or
equal to 1. If the W
ave
value is greater than 1, more remediation must be carried out until the
W
ave
is less than or equal to 1.
Alternatively, the procedure under Section 742.505(b)(3) may be used to address
cumulative effect. Under this procedure, the individual remediation objective is divided by the
number of chemicals detected in groundwater that affect specific target organs or organ
49
system. For the hypothetical site, as noted above Ethylbenzene and Toluene affect kidney and
liver. Therefore, the individual remediation objective must be divided by two. Thus, the
corrected remediation objectives now become 0.5 mg/L and 0.35 mg/L for Toluene and
Ethylbenzene, respectively. As shown below, the corrected remediation objectives are
acceptable since their weighted average is equal to one.
W
W
AVE
AVE
=
+
=
0 5
10
0 35
0 7
1
.
.
.
.
The above illustration shows that if similar-acting chemicals are present in Class I
groundwater underlying a remediation site, the Tier 1 remediation objectives in Appendix B,
Tables E may not be used without accounting for the cumulative effect. In light of this, the
commentators’ contention that the Tier 1 tables are no longer “user friendly” is true.
Especially, for the UST sites where BETX are the common contaminants of concern.
However, as noted earlier, the Agency justifies proposed changes concerning
noncarcinogenic effect of similar-acting substances on the basis of hazard quotient which is
protective of human health. The individual remediation objectives for noncarcinogens are
based upon a hazard quotient of 1. Further, the cumulative effect of a mixture of two or more
similar-acting chemicals at their respective remediation objectives could result in a hazard
quotient greater than 1, thus, posing a threat to human health. The provision proposed by the
Agency would ensure that the hazard quotient for a mixture of similar-acting chemicals to be
less than or equal to 1.
Even though the new provision proposed by the Agency appears to be justified with
regard to the noncarcinogenic effect of mixtures of similar-acting chemicals, there are a few
issues that remain unresolved because the Agency submitted the new language at the close of
the hearings and comment period. First, the Agency has not explained why it is necessary to
consider the effect of similar-acting chemicals in determining Tier 1
groundwater remediation
objectives
in light of its position that Tier 1 remediation objectives are very conservative. In
this regard, the Agency states that consideration of the effect similar-acting chemicals is
unnecessary when determining Tier 1
soil remediation objectives
. Second, the Agency also
does not provide an explanation as to why both carcinogenic and noncarcinogenic effects of
mixtures of similar-acting chemicals must be considered in determining groundwater
remediation objectives, whereas only noncarcinogenic effect needs to evaluated in determining
soil remediation objectives. The Agency asserted that even if multiple carcinogens are present
at their respective remediation objectives the cumulative risk would be within the acceptable
risk range. However, this rationale appears to be equally applicable to groundwater
remediation objectives.
The Board finds that the record does not contain adequate information to decide
whether or not to adopt all the new provisions concerning mixtures of similar-acting
chemicals. In light of this, the Board decided to open a new docket to consider the merits of
50
the proposed changes. However, for purposes of this docket, the issue of similar-acting
chemicals needs to be addressed, since based upon the information before us, the Tier 1
groundwater remediation objectives for such chemicals may not be protective of human health.
This is illustrated by the example given above concerning a site with BETX present.
Therefore, on an interim basis, the Board adopts the changes proposed pertaining only to the
noncarcinogenic effect of mixtures of similar-acting chemicals in groundwater objectives under
Tier 1. Under Tier 2, the Board accepts the Agency’s proposed language concerning the
cumulative effect of noncarcinogens under Tier 2 for soil and groundwater remediation
objectives, reformatted into two separate rules. This rule was originally proposed by the
Agency on September 16, 1996, and through the course of the hearings no participants
objected to these requirements. However, the Board does not adopt the Agency proposal that
the mixture rule be applied to both carcinogenic and noncarcinogenic contaminants in
groundwater under Tiers 1 and 2. Instead, the Board reserves this issue for Docket B as
discussed at the outset of this opinion.
Subpart H: Correction RBCA Equations R26 and R15
RBCA Equations R26 and R15 are used by an applicant to demonstrate that the
concentration of any contaminant in groundwater will meet the applicable remediation
objectives in two situations. First, they are used to demonstrate that the contaminant
concentration in groundwater within the minimum or designated maximum setback zone of an
existing potable water supply well will meet the applicable Tier 1 groundwater objective or the
Health Advisory concentration. Second, they are used to demonstrate that any groundwater
discharging into surface water meets the applicable water quality standard pursuant to 35 Ill.
Adm. Code 302.
Mr. Scott R. Green, a consultant from Conestoga-Rovers & Associates with over 12
years of environmental consulting experience, pointed out an error within the ASTM RBCA
equation R26 (Appendix C, Table C). (PC. 6.) He notes that in the last
erf
(error function)
term in the denominator of Equation R26, the constant 4 must be a 2 with their pre-established
site conditions. This error was pointed out to Mr. Green by Mr. Michael J. Ungs, a principal
scientist from Tetra Tech, Inc. with over 10 years of experience. Mr. Ungs actually found the
mistake in 1996 when ASTM published RBCA guidelines. The ASTM guidance document
credits this equation to a 1987 paper authored by Patrick A. Domenico
11
. Within Domenico’s
1987 paper, Equation R26 can have either a 4 or a 2 depending upon site conditions. ASTM
used a 4 for site conditions that warrant a 2. Mr. Ungs notes that in other written works by
Domenico (a 1985 paper and a 1990 textbook)
12
, a value 2 is used in the
erf term
instead of 4.
11
Domenico, P. 1987. An Analytical Model for Multidimensional transport of a decaying
contaminant species. Journal of Hydrology, Vol. 91, pp. 49-58.
12
Domenico, P. and G. Robbins. 1985. A New Method of Contaminant Plume Analysis.
Ground Water, Vol. 23, No. 4, pp. 476-485.
Domenico, P. and F. Schwartz. 1990. Physical and Chemical Hydrogeology. John Wiley &
Sons. New York, page 824.
51
Mr. Ungs has informed ASTM about the apparent error, but ASTM will not consider any
changes to the equation until the RBCA guidelines (ASTM E-1739-95) comes up for review.
In its public comments, the Agency agrees that that the Equation R26 should be
changed from the original ASTM model. (PC 10 and 22.) The Agency states that the vertical
dispersion assumption made in the model will be violated if Equation R26 is used in situations
where upward vertical dispersion is restricted by a water table or an impermeable geologic
layer. (PC 22 at 2.) The Agency notes that it ran Equation R26 to predict concentration of
Benzene with both 2 and 4 in the last
erf
for three distances. The modeling runs indicate that
using number 2 instead of 4 results in predicted concentrations approximately twice as much as
the concentrations when using 4 for each distance. The Agency advocates that the Board make
the change in equation R26.
IPC and ISG believe because this matter was brought up during the public comment
period and not the hearings, that the change should not be made because there has been no
opportunity for examination and rebuttal. Clayton Environmental agrees with IPC and ISG
that the Board should not make the change at this time. (PC 19.) In their additional
comments, IPC and the SRAC state that Equation R26 should be changed only when it has
been changed nationally by ASTM. (PC 20 and PC 21.)
The Equation R26 is used to model the contaminant concentration along the centerline
of a plume. The two
erf
terms in the equation predict dispersion in lateral and vertical planes.
The equation adopted by the Board is as follows:
C
C
X
U
erf
S
erf
S
X
x
source
x
x
w
y
X
d
z
(
)
exp
=
•
•
−
+
•
•
•
•
•
•
•
2
1
1
4
4
2
a
l a
a
a
In the equation originally proposed by the Agency, the value in the last
erf
term was 4.
Using the number 4 as the last
erf
term, which accounts for dispersion in the vertical plan is
incorrect. Since Equation R26 is a groundwater equation, the contamination is within the
aquifer or at least at the water table. The upward vertical direction is limited in distance. The
contaminant is not going to seep back into the soil. There cannot be infinite dispersion in the
vertical direction because of the restricted upward distance. Thus, using the number 4 in the
last
erf
denominator under-predicts the concentration of the contaminant at the centerline of a
plume at any distance downgradient. The correct form of the Domenico equation uses 2 in the
denominator to account for the lack of dispersion in the upward vertical direction.
Based on a review of all the comments and attachments, the Board concludes that the
value of the constant in the
erf
relating to vertical dispersion in the proposed Equation R26 is
not applicable when applied to most sites. Review of the written works of Domenico (see
footnotes) indicates that if the upper surface of the contaminant plume is restricted so as to
provide only downward vertical dispersion, the last
erf
value must be 2. Apparently, when
52
ASTM incorporated the equation from Domenico’s 1987 paper it did not give consideration to
vertical dispersion being limited by water table or a confining layer. In light of this, Equation
R26 is an incorrect application of Domenico’s equation.
The Board choose to change the equation now rather than await a correction by ASTM
for two reasons. First, if the correction is not implemented now, sites may be remediated to a
level less than protective of human health. Second, the need for this correction concerns the
mechanics of the equation, not the methodology. The methodology remains unchanged from
that originally proposed by the Agency after discussion with the SRAC prior to submitting its
proposal. That the need for this correction only arose during the First Notice public comment
period is regretful, but does demonstrate the effectiveness of First Notice. In this regard, the
Board notes that we have made similar corrections to certain equations in the ASTM guidelines
in: In the Matter of:
Regulation of
Petroleum Leaking Underground Storage Tanks
, R94-2
Second Notice (August 11, 1994) at pages 32 and 86.
Finally, since Equation R15 is the same equation, it is also corrected. We note that
under Tier 3 an applicant can request that the Agency approve an
erf
value of 4 when site
conditions warrant its use,
i.e.
, there is upward vertical dispersion.
Subpart I: Target Risk Level under Tier 1, Tier 2 and Tier 3 Evaluations
Section 742.915: Modifying Target Risk under Tier 3. In public comments, many of
the participants sought to allow risk levels greater than a target risk level of 10
-6
for
industrial/commercial properties under Tiers 1 and 2, as well as Tier 3. The Agency objected
on the grounds that Tier 2 is premised upon RBCA and SSL equations which also established
the pre-determined values under Tier 1. The Agency disagrees with those commentators
seeking such a relaxation arguing that the TACO process is for the most part premised on the
target risk level being 10
-6
, and any modification of the same should be demonstrated by a Tier
3 evaluation. The Agency does not believe that the beginning target risk level under Tiers 1 or
2 should be anything greater than 1 x 10
-6
because, at a minimum, this allows for the
cumulative effect of multiple contaminants without any other adjustment.
As stated above, the Board agrees with the Agency that the individual remediation
objectives established pursuant to Tiers 1 and 2 for industrial/commercial property, as well as
residential property, should not be greater than 1 x 10
-6
. Section 58.5(d) of the Act allows for
the cumulative effect to be factored in automatically since it provides a range of 1 x 10
-6
and 1
x 10
-4
for target risk. However, we agree with the Agency and the commentators that Tier 3
should allow for modifications of the target risk level, and that the requirements for such a
demonstration should be articulated in the Tier 3 rules. The following is a more detailed
discussion of this issue and the modifications proposed to define the requirements for a target
risk modification under Tier 3.
Both Gardner Carton & Douglas and Jenner & Block contend that the General
Assembly intended the adoption of different risk levels for residential and
industrial/commercial sites. In this regard, Section 58.5(d) provides in pertinent part:
53
….For carcinogens, soil and groundwater remediation objectives shall be established at
exposures that represent an excess upper-bound lifetime risk between 1 in 10,000 and 1
in 1,000,000 as appropriate for the post remedial action use, except that remediation
objectives protecting residential use shall be based on exposures that represent an
excess upper-bound lifetime risk of 1 in 1,000,000…
Gardner Carton & Douglas contends that the Agency failed to recognize the distinction made
by the General Assembly between residential properties and other industrial sites.
Gardner Carton & Douglas believes that the Agency’s position on using a risk level of
1 x 10
-6
for carcinogens is too conservative. Gardner Carton & Douglas states that using 1 x
10
-6
is more restrictive than the intent of the Title XVII and what USEPA and other states use.
Gardner Carton & Douglas also asserts that Section 58.5(d) of the Act allows exposure risks
between 1 x 10
-4
to 1 x 10
-6
depending on the post remedial use and that the proposed
regulations violate that provision of the Act. Gardner Carton & Douglas wants the Agency to
consider allowing the use of risk levels greater than 1 x 10
-6
for certain industrial/commercial
sites. Gardner Carton & Douglas cites a letter from Ann Wentz, of USEPA Underground
Storage Tank Section, to Doug Clay at the Agency, suggesting that the Agency take into
account higher risk standards for industrial sites. (PC 3.)
Jenner & Block agrees with Gardner Carton & Douglas that risk levels should be
changed for industrial/commercial sites to 10
-5
. (PC No. 18.) Jenner & Block also contends
that the General Assembly adopted different risk levels for residential and
industrial/commercial sites. Jenner & Block argues that industrial/commercial sites have other
programs to protect workers from exposure such as worker right to know laws, the
Occupational Safety and Hazard Act, and other state and local programs. Jenner & Block
also provided a list of other states who have adopted or proposed using a risk level of 1 x 10
-5
for one or more programs. Jenner & Block advocates that, at a minimum, Tier 2
industrial/commercial sites should be allowed to shift the risk level as a standard matter,
contending that if industrial/commercial sites are not allowed to use a greater risk level, they
will incur increased cleanup costs or cleanup process costs to conduct expensive risk
assessments.
IERG agrees with the Agency’s position regarding the use of the target risk levels. (PC
4 at 8.) IERG believes that allowing the risk levels to be changed only under Tier 3 by using
the risk assessment framework set forth in Section 742.915 is appropriate. However, IERG
states that the risk assessment framework fails to establish some of the factors that should be
considered when proposing or evaluating requests for changes in target risk levels. (PC 4 at
9.) IERG suggests the inclusion of the following additional requirement under Section
742.915 that provides additional guidance to the regulated community when submitting such
requests:
h) For requests modifying the target risk consistent with Section 742.900(d),
submittals may consider factors including, but not limited, to the following:
54
1) The probability of actual impact on receptors;
2) The presence of potential, rather than actual, receptors;
3) The number of receptors potentially impacted;
4) The duration of risk at the differing target levels; and
5) The impracticality or cost of remediation to achieve differing target levels.
(PC 8 at 5.)
ISG believes that within Tiers 2 and 3 the target risk level should be 1 x 10
-5
for non-
residential property. ISG states that ASTM, USEPA, and other states use a target risk level
of 1 x 10
-5
in their programs. However, ISG agrees with IERG that the Agency’s decision to
allow the change of target risk within Tier 3 with an appropriate risk assessment is acceptable.
ISG suggests that addition of the following provision to Section 742.915 to clarify the risk
assessment methodology:
h) Proposals seeking to modify the target risk consistent with Section 742.900(d)
may address factors including but not limited to one or more of the following: the
probability of actual impact on receptors, the presence of sensitive populations,
the number of receptors potentially impacted, the duration of risk at the differing
target levels, characteristics of the chemical of concern, and the technical
impracticality or cost of remediation to achieve differing target risk levels.
IPC states that shifting the target risk from 1 x 10
-6
to 1 x 10
-4
is a valid approach to
considering remedial objectives under Tier 3 and should not be automatically discounted. (PC.
8 at 6.) Further, IPC maintains that since the determination of a shift in target risk is placed in
Tier 3 so that it may be given a more thorough Agency review, the Board should consider
identifying criteria which can be used in making this decision. In this regard, IPC provides
language for an additional subsection under Section 742.915 that is essentially the same as the
additional language proposed by ISG and quoted above.
Clayton Environmental also agrees that the use of a greater than a 1 x 10
-6
risk level
should be available for industrial/commercial sites. Clayton Environmental contends that other
states have accepted 1 x 10
-4
as target risk levels for industrial/commercial property. Clayton’s
rationale is that the SSL and RBCA equations are inherently conservative, which results in
overestimating the risk from contaminants left in the soil. Finally, Clayton asks that the Tier 3
regulations outline the procedures for demonstrating that a greater target risk level at a
particular site. (PC 19 at 3 and 4.)
First, the Agency strongly disagrees with Gardner Carton & Douglas’ position that the
proposed regulations do not comply with Title XVII of the Act. The Agency maintains that
the proposed Part 742 regulations allow for a total risk greater than 1 x 10
-6
because the
regulations take into account the cumulative effects of mixtures of similar-acting chemicals,
and since most sites contain more than one contaminant that may have the same effects,
multiple pathways and multiple contaminants are generally an issue. The Agency notes that
Gardner Carton & Douglas never mentions apportionment and cumulative factors. (PC 15 at
55
9.)
Next, the Agency objects to the claims by Gardner Carton & Douglas that the General
Assembly mandated different risk levels for residential and industrial sites. The Agency
argues that Title XVII neither provides for changing the risk level in Tiers 1 or 2, nor specify
how risk ranges are to be used. The Agency insists that the General Assembly mandated
distinct treatment, but it did not specify how that was to be accomplished. The Agency feels
that the proposed regulations fulfill this mandate by the different exposure rates and exposure
duration within the tiered approach to identifying risk based remediation objectives.
Furthermore, if the Tier 2 numbers were allowed to use a target cancer risk of 1 x 10
-5
or 1 x
10
-4
, then the cumulative risk could be 1 x 10
-4
or 1 x 10
-3
which is unacceptable.
Concerning the differing risk levels for industrial/commercial sites advocated by Jenner
& Block, the Agency states that different exposures have already been considered for
industrial/commercial sites, and consequently the industrial/commercial sites have different
values for certain variables in the SSL equations and their own set of Tier 1 numbers. The
Agency stands by its position that someone working at a site should be afforded the same
protection as someone who might live there. The Agency also notes that recently, Oregon and
New Jersey agreed with Illinois in testifying in a hearing in front of the U.S. House of
Representatives on Superfund reauthorization issues that they use a 10
-6
risk goal. (PC 15 at
14.) Regarding Gardner Carton & Douglas’ claims that the USEPA Risk Assessment
Guidance for Superfund (RAGS) does not mandate the use of 1 x 10
-6
risk levels at all sites,
the Agency asserts that RAGS requires a complete risk assessment at every site which is
allowable in Tier 3. (PC 9 at 8-9.)
In response to concerns expressed by IERG, ISG and IPC, the Agency states, in its
additional comments, that it has no objections to including additional language under Section
742.915. (PC 15 at 3.) However, the Agency has made certain changes to the additional
language submitted by these participants. First, the Agency explained that it deleted the phrase
“the probability of actual impact on receptors”, since the phrase implies a probabilistic risk
assessment is necessary. The Agency notes that USEPA has found that a probabilistic risk
assessment is very difficult to use in a regulatory context. Next, the Agency also believes that
“the technical impracticality or cost of remediation to achieve differing target risk level”
should not be included because this is already covered under Section 742.920. The Agency
suggests the following be added at Section 742.915(h):
h) Proposals seeking to modify the target risk consistent with Section 742.900(d)
shall address the following factors:
1)
the presence of sensitive populations;
2)
the number of receptors potentially impacted;
3)
the duration of risk at the differing target levels; and
4)
the characteristics of the chemical of concern.
In sum, the Agency stands by its position that a target risk level greater than 1 x 10
-6
or
a hazard quotient greater than 1 may be used in Tier 3 after doing a risk assessment in
accordance with Section 742.915. The Agency also argues using the same risk level for
56
residential and industrial/commercial property under Tier 1 and Tier 2. The Agency asserts
that just because someone is working at a site instead of living there that they should not be
subject to a less protective risk level.
The Board finds that the Agency’s proposal is based on the concept of providing the
same level protection to an individual working at a site and to an individual residing at a site
under Tier 1 and Tier 2. As the Agency argued, the proposed regulations do provide for
differing remediation objectives for industrial/commercial sites under Tier 1 or Tier 2 by
considering different exposure factors. The Agency is also correct in arguing that the
proposed regulations address the additive effect of mixtures of similar-acting chemicals that
renders the overall target risk level to be higher than 1x10
-6
at a number of sites contaminated
with multiple chemicals.
Finally, the Agency’s proposal allows for the consideration of higher target risk levels
for carcinogens or hazard quotient greater than 1 for noncarcinogens under Tier 3. Section
742.900 requires any requests for changes in risk levels to be supported by a formal risk
assessment performed in accordance with Section 742.915. By doing so, the proposal ensures
that a decision to approve such changes will be based on a thorough evaluation of all relevant
factors.
Subpart J: Transfer of Institutional Controls
In their public comments, ISG and IPC raised a concern that institutional controls be
transferable. (PC 7 at 10-11 and PC 8 AT 8, respectively). They would like some clarifying
language added to Section 742.1000 to insure that these instruments are transferable. They
propose to add a subsection (d) which would say: “Institutional controls are transferable with
the property to which they apply”. They state that this issue was brought up in the January
15, 1997 hearing and that the Agency agreed that institutional controls are transferable. They
also noted that a change with respect to engineered barriers in Section 742.1100(d) was made
to allow the transfer of the responsibility for maintaining engineered controls, which are
required to be memorialized in the applicable institutional controls.
The City of Chicago agrees with ISG and IPC. (PC 13 at 3.) The Agency also agrees
and has no objection to add the above language to the proposed regulations. (PC 15 at 3.)
The Board notes that institutional controls must be recorded in the chain of title and
therefore “run with the land.” As a result, a transferee of a remediation site subject to an
institutional control takes its interest subject to the institutional control, and no action is
necessary to transfer the institutional control to the transferee. This is confirmed by Section
58.10(d), which states that a No Further Remediation Letter (which may contain institutional
controls) shall apply in favor of various entities, including a successor-in-interest of the owner
of the site; an heir or devisee of the owner of the site; a transferee of the owner of the site,
whether the transfer was by sale, bankruptcy proceeding, partition, dissolution by marriage,
settlement or adjudication of any civil action, charitable gift or bequest; and various other
entities. If the terms of an institutional control are violated, an No Further Remediation letter
57
is voidable whether or not a subsequent owner agreed to accept “transfer” of the institutional
control.
This is further confirmed by Section 58.10(e) of the Act, that states that specific acts
that may result in voidance of an NFR Letter include “the failure of the owner, operator, RA,
or any subsequent transferee
to operate or maintain preventive or engineering controls or
comply with a groundwater monitoring plan, if applicable . . . .” (415 ILCS 5/58.10(e)(2)
(emphasis supplied).)
Therefore, the Board does not believe that it is necessary to insert the language
suggested by ISG and others to allow for example, the transfer of an institutional control from
a seller to a purchaser. That transfer occurs by operation of law, and accordingly the Board
has added a provision that “Institutional controls are transferred with the property to which
they apply.” (35 Ill. Adm. Code 742.1000(d).) For the same reason, the Board has stricken a
portion of Section 742.1100(d) (in Subpart K) regarding engineered barriers:
A no further remediation determination based upon the use of engineered barriers shall
require effective maintenance of the engineered barrier. The maintenance requirements
shall be included in an institutional control under Subpart J. and are to be maintained
by the owner of the site. This responsibility shall be transferable with the property.
The stricken language is not necessary because the maintenance requirements, which must be
contained in an institutional control, run with the land, just as does the institutional control.
The Board notes that nothing in the Act precludes private arrangements between
transferors and transferees regarding the maintenance of institutional controls. For example, a
purchaser and seller may agree that the seller will retain responsibility for maintaining an
engineered barrier, and that the seller indemnify the purchaser for any damages resulting from
the seller’s failure to maintain the engineered barrier. Alternatively, it may be in a seller’s
interest to obtain a covenant from the purchaser that the purchaser will maintain an engineered
barrier and will indemnify the seller from any damages resulting from the purchaser’s failure
to maintain the engineered barrier. In addition, nothing in the Act prohibits an owner from
contracting with a consulting engineering firm for the maintenance of an engineered barrier. If
the terms of the institutional control are violated, however, a No Further Remediated Letter or
no further remediation determination is voidable, regardless of the private arrangements among
those with an interest in the property.
Determination of Class II Groundwater and other Groundwater Issues
The Agency proposed that the Board adopt procedures about how an applicant is to
demonstrate that the groundwater beneath a site is not Class I groundwater so that the
remediation objectives are designed to meet the Class II groundwater quality objectives.
There was little discussion about Appendix D on the record. However, Jenner & Block did
raise two issues related to groundwater. First, Jenner & Block questioned the need to filter
groundwater samples. Second, Jenner & Block asked that the Board define to which
58
groundwater class straddling groundwaters should be assigned. All three topics are discussed
below.
Appendix D: Procedures for Determination of Class II Groundwater. The Board has
examined the language proposed at Appendix D which describes in great detail the procedures
and criteria an applicant should use to determine and demonstrate that groundwater beneath the
site is Class II groundwater. The Board finds that these procedures, in fact, are rules. While
they may be helpful to applicants using TACO, the Board cannot adopt such rules in an
appendix. Furthermore, the Board cannot adopt rules which define which groundwaters are
Class II groundwaters without conducting rulemaking on this issue which did not occur in this
docket because the Agency offered no explanation of the procedures proposed at Appendix D.
Finally, such rules are more appropriately considered in the context of Part 620. The Board
would welcome a proposal for rules such as these by the Agency.
Use of Unfiltered Groundwater Samples. In the first set of hearings, Jenner & Block
asked the Agency whether groundwater samples should have to be filtered. The Agency
responded that it would be a site specific or a program specific determination. Filtering
groundwater samples would remove any particulate matter that may have contaminants of
concern adhered to it. The Agency believes that since the Department of Public Health does
not require residential wells to be filtered, any sites that would be designated residential
property which plans to have a well would not necessarily be fully protected.
Mr. Ray Reott of Jenner & Block provided testimony on this subject. He cites 35 Ill.
Adm. Code Section 620.510(b) which addresses the use of filtering of samples for analysis of
metals. Mr. Reott states that the Agency’s witnesses in hearings for the Part 620 rulemaking
endorsed filtering groundwater samples prior to metals analysis. (Exh. 18 at 11.) USEPA has
acknowledged that it is the dissolved metals which pose the most health risk. The Agency
states in its rebuttal and public comment that there are situations where samples will be filtered
because of high turbidity making the water unpalatable. There are also situations where
groundwater is not restricted. Therefore requiring groundwater samples to be filtered would
not be an accurate representation for all sites. If determination of whether to filter or not was
done on a case by case basis then every site would be investigated properly.
After reviewing the testimony and comments, the Board agrees with the Agency.
Filtering groundwater samples should be a site-specific or a program-specific determination.
Although the water quality criteria is based on filtered samples and the USEPA states that
drinking water suitability samples must be filtered before analysis, there is always a possibility
that the site in the future will not have restrictions concerning groundwater. Therefore, the
Board finds no need to amend the TACO rules or the Part 620 rules.
Straddling Groundwater Units. The requirement for classification of groundwater are
set forth at 35 Ill Adm. Code 620. The Part 620 rules classify groundwater into four classes.
Class I is designated as potable resource groundwater, Class II is general resource
groundwater, Class III is special resource groundwater and Class IV is other groundwater.
Based on Part 620 rules, the proposed regulations set forth a procedure to classify groundwater
59
as Class II in Appendix D. Jenner & Block expressed concerns regarding the proposed
procedures to classify Class II groundwater. There is a boundary of 10 feet below surface
beyond which all groundwater is designated to be Class I groundwater if certain
hydrogeological characteristics are met. Jenner & Block’s concern revolves around this 10
foot boundary line.
Jenner & Block interprets the Part 620 rules to mean that there can be no Class I
groundwater within 10 feet of surface, and proposes that the Board consider a proportionally
based classification system. If the majority of a water bearing unit lies within 10 feet below
the surface but crosses the 10 foot boundary line, then the water bearing unit would be
classified as Class II groundwater. Conversely, if the majority of a water bearing unit lies
below the10 foot boundary line but crosses the 10 foot line, then the water bearing unit would
be classified as Class I groundwater. Alternatively, Jenner & Block proposes that the Board
consider a classification scheme based on the location of screens within the well. Under this
scheme, all new wells would be screened that lie entirely above the 10 foot boundary line for
Class II groundwater or entirely below the 10 foot boundary line for Class I groundwater. The
crux of this scheme is to collect all of the water either above the 10 feet boundary and compare
its quality with Class II standards or below 10 foot boundary line and compare its quality to
Class I standards.
The Agency has not specifically addressed this issue in any of its comments. However,
the following discussion about proposed Appendix D reflects the Agency’s position:
Although it may be possible, it is unrealistic to try to designate two distinct classes of
groundwater within the same saturated hydrogeological unit. But, if the person conducting
the remediation can demonstrate that by cleaning the groundwater within ten feet of the
surface to Class II specifications will not degrade the groundwater greater than 10 feet below
the ground surface above Class I standards, the Agency may approve both Class I and II
standards in accordance with the location of the groundwater.
(December 10, 1996 Transcript at pages 149-167.)
Mr. Reott’s assertion that “groundwater within 10 feet of the surface cannot be Class I
groundwater is erroneous. The issue of “straddling groundwater” is not new. The Board
resolved this issue in most certain terms when it adopted the groundwater quality standards under
In the Matter of:
Groundwater Quality Standards
, R89-14(B). (November 7, 1991) The criteria
for groundwater classification is established at 35 Ill Adm. Code 620.Subpart B. Specifically,
Class I groundwater criteria is set forth at Section 620.210. In order to address the issue of
straddling groundwater, the Board added a note under Section 620.210:
Board Note: Any portion of the thickness associated with the geologic materials
as described in subsections 620.210(a)(2), (a)(3) or (a)(4) should be designated as
Class I: Potable Resource Groundwater if located 10 feet or more below the land
surface.
35 Ill. Adm. Code 620.210
60
This note clearly states that there can be Class I groundwater above the ten foot
boundary line, if it is associated with a geologic unit containing Class I groundwater. The
Board explained this point in its accompanying opinion as follows:
As a further observation on the “10-foot” rule, the Board notes that the question
has been raised whether potable groundwaters found below 10 feet but located in
geologic units that meets one of the thickness criteria only because part of the unit
is at a less than 10 feet, would still be considered Class I water (R3 at 300). The
Board intends that the answer to this question is “yes”.
(R89-14(B), (November 7, 1991) at page 12.)
Clearly, the Board resolved the issue of straddling when it adopted the
groundwater classification system under Part 620. Accordingly, the Board finds no need
to amend the TACO or Part 620 rules to address this issue.
SUMMARY
The Board hereby orders the new Part 742 to Second Notice for review by the
Joint Committee on Administrative Rules. The Board has examined the substantive issues
concerning the proposal by the Agency and the record develop during First Notice, and
accepts many of the modifications proposed by the Agency and participants. The Board
has reserved one issue for a separate Docket B. That issue is to what extent the mixture
rule adopted today should be extended to insure that risk based remediation objectives
determined using TACO are protective of human health. The Board concludes that the
rules set forth in the attached order provide a tiered approach for assessing risk to human
health when determining remediation objectives and the methodologies acceptable for
doing so on a site-specific bases. The Board further finds that these rules are
economically reasonable and technically feasible.
ORDER
The Board hereby directs that the second notice of the following revised proposal
be submitted to the Joint Committee on Administrative Rules.
TITLE 35: ENVIRONMENTAL PROTECTION
SUBTITLE G: WASTE DISPOSAL
CHAPTER I: POLLUTION CONTROL BOARD
SUBCHAPTER f: RISK BASED CLEANUP OBJECTIVES
PART 742
TIERED APPROACH TO CORRECTIVE ACTION OBJECTIVES
SUBPART A: INTRODUCTION
61
Section
742.100
Intent and Purpose
742.105
Applicability
742.110
Overview of Tiered Approach
742.115
Key Elements
742.120
Site Characterization
SUBPART B: GENERAL
Section
742.200
Definitions
742.205
Severability
742.210
Incorporations by Reference
742.215
Determination of Soil Attenuation Capacity
742.220
Determination of Soil Saturation Limit
742.225
Determination Demonstration of Compliance with Remediation Objectives
742.230
Agency Review and Approval
SUBPART C: EXPOSURE ROUTE EVALUATIONS
Section
742.300
General Exclusion of Exposure Route
742.305
Contaminant Source EvaluationContaminant Source and Free Product
Determination
742.310
Inhalation Exposure Route
742.315
Soil Ingestion Exposure Route
742.320
Groundwater Ingestion Exposure Route
SUBPART D: DETERMINING AREA BACKGROUND
Section
742.400
GeneralArea Background
742.405
Determination of Area Background for Soil
742.410
Determination of Area Background for Groundwater
742.415
Use of Area Background Concentrations
SUBPART E: TIER 1 EVALUATION
Section
742.500
Introduction Tier 1 Overview
742.505
Tier 1 Soil and Groundwater Groundwater and Soil Remediation Objectives
742.510
Tier 1 Remediation Objectives Tables
SUBPART F: TIER 2 GENERAL EVALUATION
62
Section
742.600
Introduction Tier 2 Overview
742.605
Land Use
742.610 Chemicals with Cumulative Noncarcinogenic Effects
742.615610
Chemical and Site Properties
SUBPART G: TIER 2 SOIL EVALUATION
Section
742.700
Tier 2 Soil Overview
742.705
Parameters for Soil Remediation Objective Equations
742.710
SSL Soil Equations
742.715
RBCA Soil Equations
742.720 Chemicals with Cumulative Noncarcinogenic Effects
SUBPART H: TIER 2 GROUNDWATER EVALUATION
Section
742.800
Tier 2 Groundwater Overview General
742.805
Tier 2 Groundwater Remediation Objectives
742.810
Calculations to Predict Impacts from Remaining Groundwater Contamination
SUBPART I: TIER 3 EVALUATION
Section
742.900
Tier 3 Overview Introduction
742.905
Modifications of Parameters
742.910
Alternative Models
742.915
Formal Risk Assessments
742.920
Impractical Remediation
742.925
Exposure Routes
742.930
Derivation of Toxicological Data
742.935 Agricultural Uses and Ecological Receptors (Reserved)
SUBPART J: INSTITUTIONAL CONTROLS
Section
742.1000
Institutional Controls General
742.1005
No Further Remediation Letters
742.1010
Restrictive Covenants, Deed Restrictions and Negative Easements
742.1015
Ordinances
742.1020
Highway Authority Agreements
SUBPART K: ENGINEERED BARRIERS
63
Section
742.1100
Engineered BarriersGeneral
742.1105
Engineered Barrier Requirements
742.APPENDIX A
General
Table A
Soil Saturation Limits (C
sat
) for Chemicals Whose Melting Point is Less
Than 30
0
C
Table B
Tolerance Factor (K)
Table C
Coefficients {A
N-I+1
} for W Test of Normality, for N=2(1)50
Table D
Percentage Points of the W Test for N=3(1)50
Table E
SSL Chemicals with Noncarcinogenic Toxic Effects on Specific Target
Organs/Organ Systems or Similar Modes of Action
Table F
Chemicals with Carcinogenic Toxic Effects on Specific Target
Organs/Organ Systems or Similar Modes of Action
Table F G
Range of Concentrations of Inorganic Chemicals in Background Soils
IllustrationILLUSTRATION A
Developing Soil Remediation Objectives Under the
Tiered Approach
IllustrationILLUSTRATION B
Developing Groundwater Remediation Objectives
Under the Tiered Approach
742.APPENDIX B
Tier 1 Tables and Illustrations
Table A
Tier 1 Soil Remediation Objectives for Residential Properties
Table B
Tier 1 Soil Remediation Objectives for Industrial/Commercial Properties
Table C
pH Specific Soil Remediation Objectives for Inorganics and Ionizing
Organics for the Migration to GroundwaterSoil Component Portion of the
Groundwater Ingestion Route (Class I Groundwater)
Table D
pH Specific Soil Remediation Objectives for Inorganics and Ionizing
Organics for the Migration to GroundwaterSoil Component Portion of the
Groundwater Ingestion Route (Class II Groundwater)
Table E
Tier 1 Groundwater Remediation Objectives for the Direct Ingestion of the
Groundwater Component Portion of the Groundwater Ingestion Route
Table F
Values Used to Calculate the Tier 1 Soil Remediation Objectives for the
Migration to Groundwater Soil Component Portion of the Groundwater
Ingestion Route
IllustrationILLUSTRATION A
Tier 1 Evaluation
742.APPENDIX C
Tier 2 Tables and Illustrations
Table A
SSL Equations
Table B
SSL Parameters
Table C
RBCA Equations
Table D
RBCA Parameters
Table E
Default Physical and Chemical Parameters
Table F
Methods for Determining Physical Soil Parameters
Table G
Error Function (erf)
Table H
Q/C Values by Source Area
64
Table I
K
oc
Values for Ionizing to be Substituted for k
s
When Evaluating Organics
as a Function of pH
Table J
Values to be Substituted for k
s
When Evaluating Inorganics as a Function
of pH
Table K
Parameter Estimates for Calculating Water-Filled Soil Porosity (
θ
w
)
IllustrationILLUSTRATION A
Tier 2 Evaluation for Soil
IllustrationILLUSTRATION B
Tier 2 Evaluation for Groundwater
IllustrationILLUSTRATION C
US Department of Agriculture Soil Texture
Classification
742.APPENDIX D Procedures for Determination of Class II Groundwater
AUTHORITY: Implementing Sections 22.4, 22.12, Title XVI, and Title XVII and 57 57.17 and
58.1 58.12 andauthorized by Sections 27, 57.14, and 58.5 of the Environmental Protection Act
[415 ILCS 5/22.4, 22.12, Title XVI and Title VII 57 57.17, 57.14 and 58.5] (see P.A. 88-496,
effective September 13, 1993 and P.A. 89-0431, effective December 15, 1995).
SOURCE: Adopted at 21 Ill. Reg. ______________ , effective __________________.
NOTE: Capitalization indicates statutory language.
SUBPART A: INTRODUCTION
Section 742.100
Intent and Purpose
a)
This Part sets forth procedures for use in evaluating the risk to human health posed
by environmental conditions and in developing remediation objectives for
remediation that assure such risks that achieve acceptable risk levels.
b)
The purpose of these procedures is to provide for the adequate protection of
human health and the environment based on the risks to human health posed by
environmental conditions while incorporating site related information,. to the
extent practicable, which may allow for more cost-effective site remediation.
Section 742.105
Applicability
a)
Any person, including a person required to perform investigation pursuant to the
Illinois Environmental Protection Act (415 ILCS 5/1 et seq.) (Act), may elect to
proceed under this Part to the extent allowed by State or federal law and
regulations and the provisions of this Part. A person proceeding under this Part
may do so to the extent such actions are consistent with the requirements of the
program under which site remediation is being addressed.
b)
This Part is intended to be used in conjunction with following the procedures and
requirements applicable to the following programs:
65
1)
Leaking Underground Storage Tanks (35 Ill. Adm. Code 731 and 732);
2)
Site Remediation Program (35 Ill. Adm. Code 740); and
3)
RCRA Part B Permits and Closure Plans (35 Ill. Adm. Code 724 and 725).
c)
The procedures in this Part may not be used if their use would delay response
action when timeliness is critical to address imminent and substantial threats to
human health and the environment. This Part may only be used after actions to
address such threats have been completed.
d)
Consistent with the regulation of other programs, and as approved by the Agency,
this Part may be used to develop remediation objectives to protect surface water,
sediments, or ecological concerns.This Part may be used to develop remediation
objectives to protect surface waters, sediments, or ecological concerns, when
consistent with the regulations of other programs, and as approved by the Agency.
e)
A no further remediation determination issued by the Agency prior to the effective
date of this Part pursuant to Section 4(y) of the Act or one of the programs listed
in subsection (b) of this Section that approves completion of remedial action
relative to a release shall remain in effect in accordance with the terms of the that
determination.
f)
Site specific groundwater remediation objectives determined under this Part for
contaminants of concern may exceed the groundwater quality standards established
pursuant to the rules promulgated under the Illinois Groundwater Protection Act
(415 ILCS 55/1
et seq.
) as long as done in accordance with Sections 742.805(a)
and 742.900(c)(9). (415 ILCS 5/58.5(d)(4))[415 ILCS 55].
BOARD NOTE: Sections 58.5 and 57.7 of the Act authorize the use of groundwater
remediation objectives for contaminants of concern that are greater than the groundwater
quality standards established pursuant to the Illinois Groundwater Protection Act and rules
promulgated thereunder.
g) The Agency’s issuance of a “No Further Remediation” determination pursuant to
the requirements applicable to the program under which the remediation is
performed shall be considered, while the determination is in effect,
prima facie
evidence that the contaminants of concern at the site do not, relative to
groundwater, cause or tend to cause water pollution under Section 12 (a) of the
Act or create a water pollution hazard under Section 12(d) of the Act.
g)h)
Where contaminants of concern include polychlorinated biphenyls (PCBs), a
person may need to evaluate the applicability of regulations adopted under the
Toxic Substances Control Act. (15 U.S.C. 2601) (1976).
66
Section 742.110
Overview of Tiered Approach
a)
This Part presents an approach to for developingment of remediation objectives
(see Appendix A, Illustrations A and B) that includes an option for exclusion of
pathways from further consideration, use of area background concentrations as
remediation objectives, and three tiers for selecting applicable remediation
objectives. An understanding of human exposure routes is necessary to properly
conduct an evaluation under this approach. In some cases, applicable human
exposure route(s) can be excluded from further consideration prior to any tier
evaluation. The option of Sselecting which tier or combination of tiers shall to be
used to develop remediation objectives will be is dependent on the site-specific
conditions and remediation goals. Tier 1 evaluations and Tier 2 evaluations are
not prerequisites to conducting Tier 3 evaluations.
b)
Tier 1.A Tier 1 evaluation compares the concentration of contaminants detected at
a site to the corresponding remediation objectives for residential and
industrial/commercial properties contained in Appendix B, Tables A, B, C, D, and
E. To complete a Tier 1 evaluation, the extent and concentrations of the
contaminants of concern, the groundwater class, the land use classification, human
exposure routes at the site, and, if appropriate, soil pH must be known. If
remediation objectives are developed based on industrial/commercial property use,
then institutional controls under Subpart J are required.
c)
Tier 2.A Tier 2 evaluation uses the risk based equations from the Soil Screening
Level (SSL) and Risk Based Corrective Action (RBCA) approaches' risk-based
equations listed in Appendix C, Tables A and C, respectively. In addition to the
information that is required for a Tier 1 evaluation, site-specific information is used
to calculate Tier 2 remediation objectives. As in Tier 1, Tier 2 evaluates
residential and industrial/commercial properties only. Tier 2 remediation
objectives are equally protective of human health based on identified risks and site-
specific conditions at the site. Tier 2 also considers the use of institutional controls
or engineered barriers and institutional controls in accordance with Subparts J and
K. If remediation objectives are developed based on industrial/commercial
property use, then institutional controls under Subpart J are required.
d)
Tier 3.A Tier 3 evaluation allows alternative parameters and factors, not available
under a Tier 1 evaluation or a Tier 2 evaluation, to be considered when developing
remediation objectives. A Tier 3 evaluation can be simple or complex depending
on the remediation method and the site conditions.Remediation objectives
developed for conservation and agricultural properties can only be developed
under Tier 3.
e)
Remediation objectives may be developed using area background concentrations
or any of the three tiers may be used if the evaluation is conducted in accordance
with applicable requirements in Subparts D through I. When contaminant
67
concentrations do not exceed area background concentrations or remediation
objectives developed under one of the tiers or area background procedures under
Subpart D, further evaluation under any of the other tiers is not required.
Section 742.115
Key Elements
To develop remediation objectives under this Part, the following key elements shall be addressed.
a)
Exposure Routes
1)
This Part identifies the following as potential exposure routes to be
addressed:
A)
Inhalation;
B)
Soil Iingestion;
C)
Groundwater Iingestion; and
D)
Dermal contact with soil.
2)
The evaluation of exposure routes under subsections (a)(1)(A),(a)(1)(B),
and (a)(1)(C) of this Section is required for all sites when developing
remediation objectives or excluding exposure pathways. Evaluation of the
dermal contact exposure route is required for use of RBCA equations in
Appendix C, Table C or use of formal risk assessment under Section
742.915.
3)
The groundwater ingestion exposure route is comprised of two
components portions:
A)
Migration from soil to Ggroundwater (Ssoil Ccomponent); and
B)
Direct Iingestion of Ggroundwater (Ggroundwater Ccomponent).
b)
Contaminants of Concern
The contaminants of concern to be remediated depend on the following:
1)
The materials and wastes managed at the site;
2)
The extent of the no further remediation determination being requested
from the Agency pursuant to a specific program; and
68
3)
The requirements applicable to the specific program, as listed at Section
742.105(b) ,under which the remediation is being performed.
c)
Land Use
The present and post-remediation uses of the site where exposures may occur shall
be evaluated. The land use of a site, or portion thereof, shall be classified as one of
the following:
1)
Residential property;
2)
Conservation property;
3)
Agricultural property; or
4)
Industrial/commercial property.
Section 742.120
Site Characterization
Characterization of the extent and concentrations of contamination at a site shall be performed
before beginning development of remediation objectives. The actual steps and methods taken to
characterize a site are determined by the requirements applicable to the specific program under
which site remediation is being addressed.
69
SUBPART B: GENERAL
Section 742.200
Definitions
Except as stated in this Section, or unless a different meaning of a word or term is clear from the
context, the definition of words or terms in this Part shall be the same as that applied to the same
words or terms in the Act.
"Act" means the Illinois Environmental Protection Act [(415 ILCS 5/1 et seq.)].
"ADL" means Acceptable Detection Limit, which is the detectable concentration
of a substance which is equal to the lowest appropriate Practical Quantitation
Limit (PQL) as defined in this Section.
"Agency" means the Illinois Environmental Protection Agency.
"Agricultural Property" means any real property for which its present or post-
remediation use is for planned to consist of the growing of agricultural crops for
food or feed either as harvested crops, cover crops, or as pasture. This definition
includes, but is not limited to, properties used for confinement or grazing of
livestock or poultry and for silviculture operations. Excluded from this definition
are farm residences, farm outbuildings, and agrichemical facilities.
"Area Background" means CONCENTRATIONS OF REGULATED
SUBSTANCES THAT ARE CONSISTENTLY PRESENT IN THE
ENVIRONMENT IN THE VICINITY OF A SITE THAT ARE THE RESULT
OF NATURAL CONDITIONS OR HUMAN ACTIVITIES, AND NOT THE
RESULT SOLELY OF RELEASES AT THE SITE. (Section 58.2 of the Act)
"ASTM" means the American Society for Testing and Materials.
"Board" means the Illinois Pollution Control Board.
"Cancer Risk" means a unitless probability of an individual developing cancer from
a defined exposure rate and frequency.
"Cap" means a barrier designed to prevent the infiltration of precipitation or other
surface water, or impede the ingestion or inhalation of contaminants.
"Carcinogen" means A CONTAMINANT THAT IS CLASSIFIED AS (1) A
CATEGORY A1 OR A2 CARCINOGEN BY THE AMERICAN CONFERENCE
OF GOVERNMENTAL INDUSTRIAL HYGIENISTS; OR (2) A CATEGORY
1 OR 2A/2B CARCINOGEN BY THE WORLD HEALTH ORGANIZATION'S
INTERNATIONAL AGENCY FOR RESEARCH ON CANCER; OR (3) A
"HUMAN CARCINOGEN" OR "ANTICIPATED HUMAN CARCINOGEN"
BY THE UNITED STATES DEPARTMENT OF HEALTH AND HUMAN
70
SERVICE NATIONAL TOXICOLOGICAL PROGRAM; OR (4) A
CATEGORY A OR B1/B2 CARCINOGEN BY THE UNITED STATES
ENVIRONMENTAL PROTECTION AGENCY IN the INTEGRATED RISK
INFORMATION SYSTEM OR A FINAL RULE ISSUED IN A FEDERAL
REGISTER NOTICE BY THE USEPA. (Section 58.2 of the Act)
"Class I Groundwater" means groundwater that meets the Class I: Potable
Resource Groundwater criteria set forth in 35 Illinois Administrative Code 620.
"Class II Groundwater" means groundwater that meets the Class II: General
Resource Groundwater criteria set forth in 35 Illinois Administrative Code 620.
"Conservation Property" means any real property for which present or post-
remediation use is primarily for wildlife habitat.
"Construction Worker Population" means a situation where persons who are is
engaged on a temporary basis to perform work involving invasive construction
activities including, but not limited to, personnel performing demolition, earth-
moving, building, and routine and emergency utility installation or repair activities.
"Contaminant of Concern" or "Regulated Substance of Concern" means ANY
CONTAMINANT THAT IS EXPECTED TO BE PRESENT AT THE SITE
BASED UPON PAST AND CURRENT LAND USES AND ASSOCIATED
RELEASES THAT ARE KNOWN TO THE person conducting a remediation
BASED UPON REASONABLE INQUIRY. (Section 58.2 of the Act)
"Engineered Barrier" means a barrier designed or verified using engineering
practices that limits exposure to or controls migration of the contaminants of
concern.
"Exposure Route" means the transport mechanism by which a contaminant of
concern reaches a receptor.
"Free Product" means a contaminant that is present as a non-aqueous phase liquid
for chemicals whose melting point is less than 30
o
C (e.g., liquid not dissolved in
water).
"GROUNDWATER" MEANS UNDERGROUND WATER WHICH OCCURS
WITHIN THE SATURATED ZONE AND GEOLOGIC MATERIALS WHERE
THE FLUID PRESSURE IN THE PORE SPACE IS EQUAL TO OR GREATER
THAN ATMOSPHERIC PRESSURE. (Section 3.64 of the Act)
"Groundwater Quality Standards" means the standards for groundwater as set
forth in 35 Illinois Administrative Code 620.
71
"Hazard Quotient" means the ratio of a single substance exposure level during a
specified time period to a reference dose for that substance derived from a similar
exposure period.
“Highway” means ANY PUBLIC WAY FOR VEHICULAR TRAVEL WHICH
HAS BEEN LAID OUT IN PURSUANCE OF ANY LAW OF THIS STATE, OR
OF THE TERRITORY OF ILLINOIS, OR WHICH HAS BEEN ESTABLISHED
BY DEDICATION, OR USED BY THE PUBLIC AS A HIGHWAY FOR 15
YEARS, OR WHICH HAS BEEN OR MAY BE LAID OUT AND CONNECT A
SUBDIVISION OR PLATTED LAND WITH A PUBLIC HIGHWAY AND
WHICH HAS BEN DEDICATED FOR THE USE OF THE OWNERS OF THE
LAND INCLUDED IN THE SUBDIVISION OR PLATTED LAND WHERE
THERE HAS BEEN AN ACCEPTANCE AND USE UNDER SUCH
DEDICATION BY SUCH OWNERS, AND WHICH HAS NOT BEEN
VACATED IN PURSUANCE OF LAW. THE TERM “HIGHWAY”
INCLUDES RIGHTS OF WAY, BRIDGES, DRAINAGE STRUCTURES,
SIGNS, GUARD RAILS, PROTECTIVE STRUCTURES AND ALL OTHER
STRUCTURES AND APPURTENANCES NECESSARY OR CONVENIENT
FOR VEHICULAR TRAFFIC. A HIGHWAY IN A RURAL AREA MAY BE
CALLED A “ROAD”, WHILE A HIGHWAY IN A MUNICIPAL AREA MAY
BE CALLED A “STREET”. (Illinois Highway Code, 605 ILCS 5/2-202)
“Highway Authority” means THE DEPARTMENT of Transportation WITH
RESPECT TO A STATE HIGHWAY; THE COUNTY BOARD WITH
RESPECT TO A COUNTY HIGHWAY OR A COUNTY UNIT DISTRICT
ROAD IF A DISCRETIONARY FUNCTION IS INVOLVED AND THE
COUNTY SUPERINTENDENT OF HIGHWAYS IF A MINISTERIAL
FUNCTION IS INVOLVED; THE HIGHWAY COMMISSIONER WITH
RESPECT TO A TOWNSHIP OR DISTRICT ROAD NOT IN A COUNTY
UNIT ROAD DISTRICT; OR THE CORPORATE AUTHORITIES OF A
MUNICIPALITY WITH RESPECT TO A MUNICIPAL STREET. (Illinois
Highway Code, 605 ILCS 5/2-213)
"Human Exposure Pathway" means a physical condition which may allow for a
risk to human health based on the presence of all of the following: contaminants of
concern; an exposure route; and a receptor activity at the point of exposure that
could result in contaminant of concern intake.
"Industrial/Commercial Property" means any real property that does not meet the
definition of residential property, conservation property, or agricultural property.
"Infiltration" means the amount of water entering into the ground as a result of
precipitation.
72
"Institutional Control" means a legal mechanism for imposing a restriction on land
use, as described in Subpart J.
"Man-Made Pathways" means CONSTRUCTED physical conditions THAT MAY
ALLOW FOR THE TRANSPORT OF REGULATED SUBSTANCES
INCLUDING, BUT NOT LIMITED TO, SEWERS, UTILITY LINES, UTILITY
VAULTS, BUILDING FOUNDATIONS, BASEMENTS, CRAWL SPACES,
DRAINAGE DITCHES, OR PREVIOUSLY EXCAVATED AND FILLED
AREAS. (Section 58.2 of the Act)
"Natural Pathways" means NATURAL physical conditions that may allow FOR
THE TRANSPORT OF REGULATED SUBSTANCES INCLUDING, BUT
NOT LIMITED TO, SOIL, GROUNDWATER, SAND SEAMS AND LENSES,
AND GRAVEL SEAMS AND LENSES. (Section 58.2 of the Act)
"Negative Easement" means a right in of the owner of the dominant or benefitted
estate or property to restrict the property rights of the owner of the servient or
burdened estate or property.
"Person" means an INDIVIDUAL, TRUST, FIRM, JOINT STOCK COMPANY,
JOINT VENTURE, CONSORTIUM, COMMERCIAL ENTITY,
CORPORATION (INCLUDING A GOVERNMENT CORPORATION),
PARTNERSHIP, ASSOCIATION, STATE, MUNICIPALITY, COMMISSION,
POLITICAL SUBDIVISION OF A STATE, OR ANY INTERSTATE BODY
INCLUDING THE UNITED STATES GOVERNMENT AND EACH
DEPARTMENT, AGENCY, AND INSTRUMENTALITY OF THE UNITED
STATES. (Section 58.2 of the Act)
"Point of Human Exposure" means the point(s) at which human exposure to a
contaminant of concern may reasonably be expected to occur. The point of human
exposure is at the source, unless an institutional control limiting human exposure
for the applicable exposure route has been or will be in place, in which case the
point of human exposure will be the boundary of the institutional control. Point of
human exposure may be at a different location than the point of compliance.
"PQL" means Practical Quantitation Limit or eEstimated qQuantitation lLimit,
which is the lowest concentration that can be reliably measured within specified
limits of precision and accuracy for a specific laboratory analytical method during
routine laboratory operating conditions in accordance with "Test Methods for
Evaluating Solid Wastes, Physical/Chemical Methods", EPA Publication No. SW-
846, incorporated by reference in Section 742.210. When applied to filtered water
samples, PQL includes the mMethod dDetection lLimit or eEstimated dDetection
lLimit in accordance with the applicable method revision in: "Methods for the
Determination of Organic Compounds in Drinking Water", Supplement II", EPA
Publication No. EPA/600/4-88/039; "Methods for the Determination of Organic
73
Compounds in Drinking Water, Supplement III", EPA Publication No.
EPA/600/R-95/131, all of which are incorporated by reference in Section 742.210.
"RBCA" means Risk Based Corrective Action as defined in ASTM E-1739-95, as
incorporated by reference in Section 742.210.
"RCRA" means the Resource Conservation and Recovery Act of 1976 (as
amended). (42 U.S.C. Sec. 6921 et seq.)
"Reference Concentration (RfC)" means an estimate of a daily exposure, in units of
milligrams of chemical per cubic meter of air (mg/m
3
), to the human population
(including sensitive subgroups) that is likely to be without appreciable risk of
deleterious effects during a portion of a lifetime (up to approximately seven years,
subchronic) or for a lifetime (chronic).
"Reference Dose (RfD)" means an estimate of a daily exposure, in units of
milligrams of chemical per kilogram of body weight per day (mg/kg/d), to the
human population (including sensitive subgroups) that is likely to be without
appreciable risk of deleterious effects during a portion of a lifetime (up to
approximately seven years, subchronic) or for a lifetime (chronic).
"Regulated Substance" means ANY HAZARDOUS SUBSTANCE AS DEFINED
UNDER SECTION 101(14) OF THE COMPREHENSIVE ENVIRONMENTAL
RESPONSE, COMPENSATION, AND LIABILITY ACT OF 1980 (P.L. 96-510)
AND PETROLEUM PRODUCTS INCLUDING CRUDE OIL OR ANY
FRACTION THEREOF, NATURAL GAS, NATURAL GAS LIQUIDS,
LIQUEFIED NATURAL GAS, OR SYNTHETIC GAS USABLE FOR FUEL
(OR MIXTURES OF NATURAL GAS AND SUCH SYNTHETIC GAS).
(Section 58.2 of the Act)
"Residential Property" MEANS ANY REAL PROPERTY THAT IS USED FOR
HABITATION BY INDIVIDUALS, OR properties where children have the
opportunity for exposure to contaminants through soil ingestion or inhalation at
educational facilities, health care facilities, child care facilities, or outdoor
recreational areas playgrounds.
"Restrictive Covenant or Deed Restriction" means a provision placed in a deed
limiting the use of the property and prohibiting certain uses. (Black's Law
Dictionary, 5th Edition)
“Right of Way” means THE LAND, OR INTEREST THEREIN, ACQUIRED
FOR OR DEVOTED TO A HIGHWAY. (Illinois Highway Code, 605 ILCS 5/2-
217)
74
"Site" means ANY SINGLE LOCATION, PLACE, TRACT OF LAND OR
PARCEL OF PROPERTY, OR PORTION THEREOF, INCLUDING
CONTIGUOUS PROPERTY SEPARATED BY A PUBLIC RIGHT-OF-WAY.
(Section 58.2 of the Act)
"Slurry Wall" means a man-made barrier made of geologic material which is
constructed to prevent or impede the movement of contamination into a certain
area.
"Soil Saturation Limit (C
sat
)" means the contaminant concentration at which soil
pore air and pore water are saturated with the chemical and the adsorptive limits of
the soil particles have been reached.
"Solubility" means a chemical specific maximum amount of solute that can dissolve
in a specific amount of solvent (groundwater) at a specific temperature.
“SPLP” means Synthetic Precipitation Leaching Procedure (Method 1312) as
published in “Test Methods for Evaluating Solid Waste, Physical/Chemical
Methods”, USEPA Publication number SW-846, as incorporated by reference in
Section 742.210.
"SSL" means Soil Screening Levels as defined in USEPA's Soil Screening
Guidance: User's Guide and Technical Background Document, as incorporated by
reference in Section 742.210.
"Stratigraphic Unit" means a site-specific geologic unit of native deposited material
and/or bedrock of varying thickness (e.g., sand, gravel, silt, clay, bedrock, etc.). A
change in stratigraphic unit is recognized by a clearly distinct contrast in geologic
material or a change in physical features within a zone of gradation. For the
purposes of this Part, a change in stratigraphic unit is identified by one or a
combination of differences in physical features such as texture, cementation, fabric,
composition, density, and/or permeability of the native material and/or bedrock.
"TCLP" means Toxicity Characteristic Leaching Procedure (Method 1311) as
published in "Test Methods for Evaluating Solid Waste, Physical/Chemical
Methods," U.S.EPAUSEPA Publication number SW-846, as incorporated by
reference in Section 742.210.
"Total Petroleum Hydrocarbon (TPH)" means the additive total of all petroleum
hydrocarbons found in an analytical sample.
"Volatile Organic Compounds (VOCs)" means organic chemical analytes identified
as volatiles as published in "Test Methods for Evaluating Solid Waste,
Physical/Chemical Methods," U.S.EPAUSEPA Publication number SW-846
(incorporated by reference in Section 742.210), method numbers 8010, 8011,
75
8015, 8020, 8021, 8030, 8031, 8240, 8260, 8315, and 8316. For analytes not
listed in any category in those methods, those analytes which have a boiling point
less than 200
0
C and a vapor pressure greater than 0.1 Torr (mm Hg) at 20
0
C.
Section 742.205
Severability
If any provision of this Part or its application to any person or under any circumstances is
adjudged invalid, such adjudication shall not affect the validity of this Part as a whole or any
portion not adjudged invalid.
Section 742.210
Incorporations by Reference
a)
The Board incorporates the following material by reference:
ASTM. American Society for Testing and Materials, 1916 Race Street,
Philadelphia, PA 19103, (215) 299-5400
ASTM D 2974-87, Standard Test Methods for Moisture, Ash and Organic
Matter of Peat and Other Organic Soils, approved May 29, 1987,
(reapproved 1995).
ASTM D 2488-93, Standard Practice for Description and Identification of
Soils (Visual-Manual Procedure), approved September 15, 1993.
ASTM D 1556-90, Standard Test Method for Density and Unit Weight of
Soil in Place by the Sand-Cone Method, approved June 29, 1990.
ASTM D 2167-94, Standard Test Method for Density and Unit Weight of
Soil in Place by the Rubber Balloon Method, approved March 15, 1994.
ASTM D 2922-91, Standard Test Methods for Density of Soil and Soil-
Aggregate in Place by Nuclear Methods (Shallow Depth), approved
December 23, 1991.
ASTM D 2937-94, Standard Test Method for Density of Soil in Place by
the Drive-Cylinder Method, approved June 15, 1994.
ASTM D 854-92, Standard Test Method for Specific Gravity of Soils,
approved November 15, 1992.
ASTM D 2216-92, Standard Method for Laboratory Determination of
Water (Moisture) Content of Soil and Rock, approved June 15, 1992.
76
ASTM D 4959-89, Standard Test Method for Determination of Water
(Moisture) Content of Soil by Direct Heating Method, approved June 30,
1989 (reapproved 1994).
ASTM D 4643-93, Standard Test Method for Determination of Water
(Moisture) Content of Soil by the Microwave Oven Method, approved July
15, 1993.
ASTM D 5084-90, Standard Test Method for Measurement of Hydraulic
Conductivity of Saturated Porous Materials Using a Flexible Wall
Permeameter, approved June 29, 1990.
ASTM D 422-63, Standard Test Method for Particle-Size Analysis of
Soils, approved November 21, 1963 (reapproved 1990).
ASTM D 1140-92, Standard Test Method for Amount of Material in Soils
Finer than the No. 200 (75
μ
m) Sieve, approved November 15, 1992.
ASTM D 3017-88, Standard Test Method for Water Content of Soil and
Rock in Place by Nuclear Methods (Shallow Depth), approved May 27,
1988.
ASTM D 4525-90, Standard Test Method for Permeability of Rocks by
Flowing Air, approved May 25, 1990.
ASTM D 2487-93, Standard Test Method for Classification of Soils for
Engineering Purposes, approved September 15, 1993.
ASTM E 1527-93, Standard Practice for Environmental Site Assessments:
Phase I Environmental Site Assessment Process, approved March 15,
1993. Vol. 11.04.
ASTM E 1739-95, Standard Guide for Risk-Based Corrective Action
Applied at Petroleum Release Sites, approved September 10, 1995.
Barnes, Donald G. and Dourson, Michael. (1988). Reference Dose (RfD):
Description and Use in Health Risk Assessments.
Regulatory Toxicology and
Pharmacology
. 8, 471-486.
GPO. Superintendent of Documents, U.S. Government Printing Office,
Washington, DC 20401, (202) 783-3238.
USEPA Guidelines for Carcinogenic Risk Assessment, 51 Fed. Reg.
33992-34003, (September 24, 1986).
77
"Test Methods for Evaluating Solid Waste, Physical/Chemical Methods,"
U.S.EPAUSEPA Publication number SW-846 (Third Edition, November,
1986), as amended by Updates I and IIA (Document Number 955-001-
00000-1)(contact U.S.EPAUSEPA, Office of Solid Waste, for Update
IIA).
"Methods for the Determination of Organic Compounds in Drinking
Water", EPA Publication No. EPA/600/4-88/039 (December 1988
(Revised July 1991)).
"Methods for the Determination of Organic Compounds in Drinking Water,
Supplement II", EPA Publication No. EPA/600/R-92/129 (August 1992).
"Methods for the Determination of Organic Compounds in Drinking Water,
Supplement III", EPA Publication No. EPA/600/R-95/131 (August 1995).
IRIS. Integrated Risk Information System, National Center for Environmental
Assessment, U.S. Environmental Protection Agency, 26 West Martin Luther King
Drive, MS-190, Cincinnati, OHhio 45268. (513) 569-7254.
"Reference Dose (RfD): Description and Use in Health Risk
Assessments", Background Document 1A, (March 15, 1993).
"EPA Approach for Assessing the Risks Associated with Chronic
Exposures to Carcinogens", Background Document 2, (January 17, 1992).
Nelson, D.W., and L.E. Sommers. 1982. Total carbon, organic carbon, and
organic matter. In: A.L. Page (ed.),
Methods of Soil Analysis. Part 2. Chemical
and Microbiological Properties. 2nd Edition
, p.p pp. 539-579, American Society
of Agronomy. Madison, WI.
NTIS. National Technical Information Service, 5285 Port Royal Road,
Springfield, VA 22161, (703) 487-4600.
"Dermal Exposure Assessment: Principales and Applications", EPA
Publication No. EPA/600/8-91/011B, (January 1992).
"Exposure Factors Handbook", EPA Publication No. EPA/600/8-89/043,
(July 1989).
"Risk Assessment Guidance for Superfund, Vol. I; Human Health
Evaluation Manual, Supplemental Guidance: Standard Default Exposure
Factors", OSWER Directive 9285.6-03, (March 1991).
78
“Rapid Assessment of Exposure to Particulate Emissions from Surface
Contamination Sites,” EPA Publication No. EPA/600/8-85/002 (February
1985), PB 85-192219.
"Risk Assessment Guidance for Superfund, Volume I; Human Health
Evaluation Manual (Part A)", Interim Final, EPA Publication No.
EPA/540/1-89/002, (December 1989).
"Risk Assessment Guidance for Superfund, Volume I; Human Health
Evaluation Manual, Supplemental Guidance, Dermal Risk Assessment
Interim Guidance", Draft, (August 18, 1992).
"Soil Screening Guidance: Technical Background Document", EPA
Publication No. EPA/540/R-95/128, PB96-963502 (May 1996).
"Soil Screening Guidance: User's Guide", EPA Publication No.
EPA/540/R-96/018, PB96-963505 (April 1996).
"Superfund Exposure Assessment Manual", EPA Publication No.
EPA/540/1-88/001, (April 1988).
RCRA Facility Investigation Guidance, Interim Final, developed by USEPA (EPA
530/SW-89-031), 4 volumes, (May 1989).
b)
CFR (Code of Federal Regulations). Available from the Superintendent of
Documents, U.S. Government Printing Office, Washington, D.C. 20402 (202)
783-3238:
40 CFR 761.120 (1993).
c)
This Section incorporates no later editions or amendments.
Section 742.215
Determination of Soil Attenuation Capacity
a)
The concentrations of organic contaminants of concern remaining in the soil shall
not exceed the attenuation capacity of the soil, as determined under subsection (b)
of this Section.
b)
The soil attenuation capacity is not exceeded if:
1)
The sum of the organic contaminant residual concentrations analyzed for
the purposes of the remediation program for which the analysis is
performed, at each discrete sampling point, is less than the natural organic
carbon fraction of the soil. If the information relative to the concentration
of other organic contaminants is available, such information shall be
79
included in the sum. The natural organic carbon fraction (
f
oc
) shall be
either:
A)
A default value of 6000 mg/kg for soils within the top meter and
2000 mg/kg for soils below one meter of the surface; or
B)
A site-specific value as measured by ASTM D2974-87, Nelson and
Sommers, or by SW-846 Method 9060: Total Organic Carbon, as
incorporated by reference in Section 742.210;.
2)
The total petroleum hydrocarbon concentration is less than the natural
organic carbon fraction of the soil as demonstrated using a method
approved by the Agency. The method selected shall be appropriate for the
contaminants of concern to be addressed; or
3)
Another method, approved by the Agency, shows that the soil attenuation
capacity is not exceeded.
Section 742.220
Determination of Soil Saturation Limit
a)
For any organic contaminant that has a melting point below 30
0
C, the remediation
objective for the inhalation exposure route developed under Tier 2 or Tier 3 shall
not exceed the soil saturation limit, as determined under subsection (c) of this
Section.
b)
For any organic contaminant, the remediation objective under Tier 2 or Tier 3 for
the migration to groundwater portion soil component of the groundwater ingestion
exposure route shall not exceed the soil saturation limit, as determined under
subsection (c) of this Section.
c)
The soil saturation limit shall be:
1)
The value listed in Appendix A, Table A for that specific contaminant;
2)
A value derived from Equation S29 in Appendix C, Table A; or
3)
A value derived from another method approved by the Agency.
80
Section 742.225
Demonstration Determination of Compliance with Remediation Objectives
Compliance is achieved if each sample result does not exceed that respective remediation
objective unless a person elects to proceed under subsections (c), (d) and (e) of this Section.
a)
Compliance with groundwater remediation objectives developed under Subparts D
through F and H through I shall be demonstrated determined by comparing the
contaminant concentrations of discrete samples at each sample point to the
applicable groundwater remediation objective. Sample points shall be determined
by the program under which remediation is performed.
b)
Unless the person elects to composite samples or average sampling results as
provided in subsections (c) and (d) of this Section, compliance with soil
remediation objectives developed under Subparts D through G and I shall be
demonstrated determined by comparing the contaminant concentrations of discrete
samples to the applicable soil remediation objective.
Compliance is achieved if each sample result does not exceed that respective
remediation objective.
1)
Except as provided in subsections (c) and (d) of this Section, compositing
of samples is not allowed.
2)
Except as provided in subsection (c) and (d) of this Section, averaging of
sample results is not allowed.
3)
Notwithstanding subsections (c) and (d) of this Section, compositing of
samples and averaging of sample results is not allowed for the construction
worker population.
4)
The number of sampling points required to demonstrate compliance is
determined by the requirements applicable to the program under which
remediation is performed.
c)
If a person chooses to composite soil samples or average soil sample results to
demonstrate determine compliance relative to the migration to groundwater soil
component of the groundwater ingestion exposure route, the following
requirements apply:
1)
A minimum of two sampling locations for every 0.5 acre of contaminated
area is required, with discrete samples at each sample location obtained at
every two feet of depth, beginning at six inches below the ground surface
and continuing through the zone of contamination. Alternatively, a
sampling method may be approved by the Agency based on an
appropriately designed site-specific evaluation. Samples obtained at or
below the water table shall not be used in compositing or averaging.
81
2)
For contaminants of concern other than volatile organic contaminants:
A)
Discrete samples from the same boring may be composited.
B)
Discrete sample results from the same boring may be averaged.
3)
For volatile organic contaminants:
A)
Compositing of samples is not allowed.
B)
Discrete sample results from the same boring may be averaged.
d)
If a person chooses to composite soil samples or average soil sample results to
determine compliance relative to the inhalation exposure route or the soil ingestion
exposure route, the following requirements apply:
1)
Unless an alternative method is approved by the Agency, a minimum of
twenty-four (24) aliquots per 0.5 acre, to be collected within the area of
contamination, is required. No more than 6 aliquots of equal volume shall
be composited into one sample. Samples composited must be located
proximate to each other. Each discrete sample shall be obtained at a depth
of one foot or less.
2)
Unless an alternative method is approved by the Agency based on an
appropriately designed site-specific evaluation, for contaminants of concern
other than volatile organic contaminants:
A)
Each 0.5 acre portion of contaminated area of a site may be divided
into quadrants of equal size and shape. The samples within the
quadrant may be composited.
B)
Averaging of sample results taken from separate quadrants is not
allowed.
3)
For volatile organic contaminants compositing of samples is not allowed.
Discrete sample results from the same quadrant may be averaged.
If a person chooses to composite soil samples or average soil sample results to
demonstrate compliance relative to the inhalation exposure route or ingestion
exposure route, the following requirements apply:
1)
A person shall submit a sampling plan for Agency approval, based upon a
site-specific evaluation;
82
2)
For volatile organic compounds, compositing of samples is not allowed;
and
3)
All samples shall be collected within the contaminated area.
e)
For purposes of calculatingWhen averaging under this Section, if no more than 50
percent of sample results are reported as "non-detect", "no contamination", "below
detection limits", or similar terms, such results shall be included in the averaging
calculation as one-half of the reported analytical detection limit for the
contaminant. If more than 50 percent of sample results are "non-detect", another
statistically valid procedure acceptable approved to by the Agency may be used to
determine an average.
f)
A person may propose an alternative method for determining compliance with
remediation objectives.
Section 742.230
Agency Review and Approval
a)
Documents and requests filed with the Agency under this Part shall be submitted in
accordance with the procedures applicable to the specific program under which
remediation is performed.
b)
Agency review and approval of documents and requests under this Part shall be
performed in accordance with the procedures applicable to the specific program
under which the remediation is performed (e.g., 35 Ill. Adm. Code 732, Subpart E
for petroleum leaking underground storage tanks).
SUBPART C: EXPOSURE ROUTE EVALUATIONS
Section 742.300
Exclusion of Exposure Route General
a)
This Subpart sets forth requirements to demonstrate that an actual or potential
impact to a receptor or potential receptor from a contaminant of concern can be
excluded from consideration from one or more exposure routes. As an alternative
to the use of the requirements in this Part, a person may use the procedures for
evaluation of exposure routes under Tier 3 as set forth in Section 742.925. If an
evaluation under this Part demonstrates the applicable requirements for excluding
an exposure route are met, then the exposure route is excluded from consideration
and no remediation objective(s) need be developed for that exposure route.
ab)
No exposure route may be excluded from consideration until characterization of
the extent and concentrations of contaminants of concern at a site has been
performed. The actual steps and methods taken to characterize a site shall be
determined by the specific program requirements under which the site remediation
is being addressed.
83
b) The inhalation exposure route may be excluded from consideration if the
requirements of Sections 742.305 and 742.310 are met.
c)
As an alternative to the use of the requirements in this Part, a person may use the
procedures for evaluation of exposure routes under Tier 3 as set forth in Section
742.925.The soil ingestion exposure route may be excluded from consideration if
the requirements of Sections 742.305 and 742.315 are met.
d) The groundwater ingestion exposure route may be excluded from consideration if
the requirements of Sections 742.305 and 742.320 are met.
Section 742.305
Contaminant Source and Free Product Determination
No exposure route shall be excluded from consideration relative to a contaminant of concern
unless the following requirements are met:
a)
The sum of the concentrations of all organic contaminants of concern shall not
exceed the attenuation capacity of the soil as determined under Section 742.215;
b)
The concentrations of any organic contaminants of concern remaining in the soil
shall not exceed the soil saturation limit as determined under Section 742.220;
c)
Any soil which contains contaminants of concern shall not exhibit any of the
characteristics of reactivity for hazardous waste as determined under 35 Ill. Adm.
Code 721.123;
d)
Any soil which contains contaminants of concern shall not exhibit a pH less than or
equal to 2.0 or greater than or equal to 12.5, as determined by SW-846 Method
9040B:pH Electrometric for soils with 20 percent or greater aqueous (moisture)
content or by SW-846 Method 9045C:Soil pH for soils with less than 20 percent
aqueous (moisture) content as incorporated by reference in Section 742.210; and
e)
Any soil which contains contaminants of concern in the following list of inorganic
chemicals or their salts shall not exhibit any of the characteristics of toxicity for
hazardous waste as determined by 35 Ill. Adm. Code 721.124, or an alternative
method approved by the Agency: arsenic, barium, cadmium, chromium, lead,
mercury, selenium, or silver.
84
Section 742.310
Inhalation Exposure Route
The inhalation exposure route may be excluded from consideration if:
a)
The requirements of Sections 742.300 and 742.305 are met; and
b)
An institutional control, in accordance with Subpart J, is in place that meets the
following requirements:
1) Requires compliance with the requirements of subsection (c ) of this
section, andThe concentration of any contaminant of concern within ten
feet of the land surface or within ten feet of any man-made pathway shall
not exceed the Tier 1 remediation objective under Subpart E for the
inhalation exposure route; or
2) An engineered barrier, as set forth in Subpart K and approved by the
Agency, is in place; and
3)
Requires safety precautions for the construction worker populations if the
Tier 1 construction worker remediation objectives are exceeded. (e.g., use
of appropriate personal protective equipment, if applicable).
c1) The concentration of any contaminant of concern within ten feet of the land
surface or within ten feet of any man-made pathway shall not exceed the
Tier 1 remediation objective under Subpart E for the inhalation exposure
route; or
2) An engineered barrier, as set forth in Subpart K and approved by the
Agency, is in place.
Section 742.315
Soil Ingestion Exposure Route
The soil ingestion exposure route may be excluded from consideration if:
a)
The requirements of Sections 742.300 and 742.305 are met; and
b)
An institutional control, in accordance with Subpart J, is in place that meets the
following requirements:
1)
Requires compliance with the requirements of subsection (c ) of this
section andThe concentration of any contaminant of concern within three
feet of the land surface shall not exceed the Tier 1 remediation objective
85
under Subpart E for the ingestion of soil exposure route; or
2) An engineered barrier, as set forth in Subpart K and approved by the
Agency, is in place; and
32)
Requires safety precautions for the construction worker population if the
Tier 1 construction worker remediation objectives are exceeded. (e.g., use
of appropriate personal protective equipment, if applicable).
c1) The concentration of any contaminant of concern within ten feet of the land
surface or within ten feet of any man-made pathway shall not exceed the
Tier 1 remediation objective under Subpart E for the inhalation exposure
route; or
2) An engineered barrier, as set forth in Subpart K and approved by the
Agency, is in place.
Section 742.320
Groundwater Ingestion Exposure Route
The groundwater ingestion exposure route may be excluded from consideration if:
a)
The requirements of Sections 742.300 and 742.305 are met;
b) To the maximum extent practicable, The corrective action measures have been
completed to remove any free product to the maximum extent practicable.
bc)
The source of the release is not located within the minimum or designated
maximum setback zone as a potable water supply well nor or within a regulated
recharge area of a potable water supply well;
d)
As demonstrated in accordance with Section 742.1015Subpart J, for any area
within 2500 feet from the source of the release, an ordinance adopted by a unit of
local government is in place that effectively prohibits the installation of potable
water supply wells (and the use of such wells);. under Section 742.1015 of this
Part; the use of groundwater as a potable supply of water, except at points of
withdrawal by the unit of local government, is in place;
d e)
As demonstrated using Equation R26, in Appendix C, Table C, in accordance with
Section 742.810, the concentration of any contaminant of concern in groundwater
within the minimum or designated maximum setback zone of an existing potable
water supply well will meet the applicable Tier 1 groundwater remediation
objective; and
e f)
As demonstrated using Equation R26, in Appendix C, Table C, in accordance with
Section 742.810, the concentration of any contaminant of concern in groundwater
86
discharging into a surface water will meet the applicable surface water quality
standard under 35 Ill. Adm. Code 302.
SUBPART D: DETERMINING AREA BACKGROUND
Section 742.400
Area Background General
This Subpart provides procedures for determining area background concentrations for
contaminants of concern. Except as described in Section 742.415(c) and (d) of this Subpart, area
background concentrations may be used as remediation objectives for contaminants of concern at
a site.
Section 742.405
Determination of Area Background for Soil
a)
Soil sampling results shall be obtained for purposes of determining area
background levels in accordance with the following procedures:
1)
For volatile organic contaminants, sample results shall be based on discrete
samples;
2)
Unless an alternative method is approved by the Agency, for contaminants
other than volatile organic contaminants, sample results shall be based on
discrete samples or composite samples. If a person elects to use composite
samples, each 0.5 acre of the area to be sampled shall be divided into
quadrants and 5 aliquots of equal volume per quadrant shall be composited
into 1 sample;
3)
Samples shall be collected from similar depths and soil types, which shall be
consistent with the depths and soil types in which maximum levels of
contaminants maxima are found in the areas of known or suspected
releases; and
4)
Samples shall be collected from areas of the site or adjacent to the site that
are unaffected by known or suspected releases at or from the site. If the
sample results show an impact from releases at or from the site, then the
sample results shall not be included in determining area background levels
under this Part.
b)
Area background shall be determined according to one of the following
approaches procedures:
1)
Statewide Area Background Approach:
A)
The maximum value of the range of concentrations of inorganic
chemicals in background soils listed in Appendix A, Table F G may
87
be used as the upper limit of the area background concentration for
the site. The first column to the right of the chemical name presents
the range of concentrations of inorganic chemicals in background
soils for counties within Metropolitan Statistical Areas. Counties
within Metropolitan Statistical Areas are identified in Appendix A,
Table F G, Footnote a. Sites located in counties outside
Metropolitan Statistical Areas shall use the range of concentrations
of inorganic chemicals in background soils shown in the second
column to the right of the chemical name.
B)
Soil area background concentrations determined according to this
statewide area background approach shall be used as provided in
Section 742.415(b) of this Part(1). For each parameter whose
sampling results demonstrate concentrations above those in
Appendix A, Table F G, the person shall develop appropriate soil
remediation objectives in accordance with this Part, or may
determine area background in accordance with the procedures
specified in subsection (b)(2) of this Section.
2)
A statistically valid approach for determining area background
concentrations appropriate for the characteristics of the data set, and
approved by the Agency.
Section 742.410
Determination of Area Background for Groundwater
a)
Groundwater sampling results shall be obtained for purposes of determining area
background in accordance with the following procedures:
1)
Samples shall be collected from areas of the site or adjacent to the site that
are unaffected by releases at the site;
2)
The background monitoring wells, as determined in consultation with the
Agency, shall be sufficient in number to account for the spatial and
temporal variability, size, and number of known or suspected off-site
releases of contaminants of concern, and the hydrogeological setting of the
site;
3)
The samples shall be collected in consecutive quarters for a minimum of
one year for each well unless or another sample schedule is approved by
the Agency;
4)
The samples shall be collected from the same stratigraphic unit(s) as the
groundwater contamination at the site; and
88
5)
The background monitoring wells shall be located hydraulically upgradient
from the release(s) of contaminants of concern, unless a person
demonstrates to the Agency approves that the upgradient location is
undefinable or infeasible.
b)
Area background shall be determined according to one of the following
approachesprocedures:
1)
Prescriptive Approach:
A)
If more than 15 percent of the groundwater sampling results for a
chemical obtained in accordance with Section 742.410(a) are less
than the appropriate detection limit for that chemical, the
Prescriptive Approach may not be used for that chemical. If 15
percent or less of the sampling results are less than the appropriate
detection limit, a concentration equal to one-half the detection limit
shall be used for that chemical in the calculations contained in this
Prescriptive Approach.
B)
The groundwater sampling results obtained in accordance with
Section 742.410(a) shall be used to determine if the sample set is
normally distributed. The Shapiro-Wilk Test of Normality shall be
used to determine whether the sample set is normally distributed, if
the sample set for the background well(s) contains 50 or fewer less
samples, to determine whether the sample set is normally
distributed. Values necessary for the Shapiro-Wilk Test of
Normality shall be determined using Appendix A, Tables E and F C
and D. If the computed value of W is greater than the 5 percent
Critical Value in Appendix A, Table D, the sample set shall be
assumed to be normally distributed, and the Prescriptive Approach
is allowed. If the computed value of W is less than 5 percent
Critical Value in Appendix A, Table D, the sample set shall be
assumed to not be normally distributed, and the Prescriptive
Approach shall not be used.
C)
If the sample set contains at least ten sample results, the Upper
Tolerance Limit (UTL) of a normally distributed sample set may be
calculated using the mean (x) and standard derration deviation(s),
from:
UTL = x + (K
•
s),
where K = the one-sided normal tolerance factor for estimating the
95 percent upper confidence limit of the 95th percentile of a normal
89
distribution. Values for K shall be determined using Appendix A,
Table B.
D)
If the sample set contains at least ten sample results, the UTL shall
be the upper limit of the area background concentration for the site.
If the sample set contains less than ten sample results, the maximum
value of the sample set shall be the upper limit of the area
background concentration for the site.
E)
This Prescriptive Approach shall not be used for determining area
background for the parameter pH.
2)
Another statistically valid approach for determining area background
concentrations appropriate for the characteristics of the data set, and
approved by the Agency.
Section 742.415
Use of Area Background Concentrations
a)
A person may request that area background concentrations determined pursuant to
Sections 742.405 and 742.410 be used according to the provisions of Section
742.415(b)subsection (b) of this Section. Such request shall address the following:
1)
The natural or man-made pathways of any suspected off-site contamination
reaching the site;
2)
Physical and chemical properties of suspected off-site contaminants of
concern reaching the site; and
3)
The location and justification of all background sampling points.
b)
Except as specified in Section 742.415 subsections (c) and (d) of this Section, an
area background concentrations may be used as follows:
1)
If determined under Sections 742.405 or 742.410, to To support a request
to exclude a chemical as a contaminant of concern from further
consideration for remediation at a site due to its presence as a result of
background conditions; or
2)
If determined under Sections 742.405 or 742.410, as As a remediation
objectives for a contaminants of concern at a site in lieu of an remediation
objectives developed pursuant to the other procedures of this Part.
c)
An aArea background concentrations shall not be used IN THE EVENT THAT
THE AGENCY HAS DETERMINED IN WRITING THAT THE
BACKGROUND LEVEL FOR A REGULATED SUBSTANCE POSES AN
90
ACUTE THREAT TO HUMAN HEALTH OR THE ENVIRONMENT AT THE
SITE WHEN CONSIDERING THE POST-REMEDIAL ACTION LAND USE.
(Section 58.5(b)(3) of the Act)
d)
IN THE EVENT THAT THE CONCENTRATION OF A REGULATED
SUBSTANCE OF CONCERN ON THE SITE EXCEEDS A REMEDIATION
OBJECTIVE ADOPTED BY THE BOARD FOR RESIDENTIAL LAND USE,
THE PROPERTY MAY NOT BE CONVERTED TO RESIDENTIAL USE
UNLESS SUCH REMEDIATION OBJECTIVE OR AN ALTERNATIVE RISK-
BASED REMEDIATION OBJECTIVE FOR THAT REGULATED
SUBSTANCE OF CONCERN IS FIRST ACHIEVED. If the land use is
restricted, there shall be an institutional control in place in accordance with
Subpart J. (Section 58.5(b)(2) of the Act)
SUBPART E: TIER 1 EVALUATION
Section 742.500
Tier 1 Evaluation Overview Introduction
a)
A Tier 1 evaluation compares the concentration of each contaminants of concern
detected at a site to the baseline remediation objectives provided in Appendix B,
Tables A, B, C, D, and E. Use of Tier 1 remediation objectives requires only
limited site-specific information: concentrations of contaminants of concern,
groundwater classification, land use classification, and, if appropriate, soil pH.
(sSee Appendix B, Illustration A).
b)
Although Tier 1 allows for differentiation between residential and
industrial/commercial property use of a site, an institutional control under Subpart
J is are required where remediation objectives are based on an
industrial/commercial property use.
c)
Any given exposure route is not a concern if the concentrations of each
contaminants of concern detected at the site is are all below the Tier 1 values of
that given route. In a such cases, no further evaluation of that route is necessary.
Section 742.505
Tier 1 Soil and Groundwater Remediation Objectives
a)
Soil
1)
Inhalation Exposure Route
A)
The Tier 1 soil remediation objectives for this exposure route based
upon residential property use are listed in Appendix B, Table A.
91
B)
The Tier 1 soil remediation objectives for this exposure route based
upon industrial/commercial property use are listed in Appendix B,
Table B. Soil remediation objective determinations relying on this
table require use of institutional controls in accordance with
Subpart J.
2)
Ingestion Exposure Route
A)
The Tier 1 soil remediation objectives for this exposure route based
upon residential property use are listed in Appendix B, Table A.
B)
The Tier 1 soil remediation objectives for this exposure route based
upon industrial/commercial property use are listed in Appendix B,
Table B. Soil remediation objective determinations relying on this
table require use of institutional controls in accordance with
Subpart J.
3)
Migration to Groundwater Soil Component Portion of the Groundwater
Ingestion Route
A)
The Tier 1 soil remediation objectives for this exposure route based
upon residential property use are listed in Appendix B, Table A.
B)
The Tier 1 soil remediation objectives for this exposure route based
upon industrial/commercial property use are listed in Appendix B,
Table B.
C)
The pH-dependent Tier 1 soil remediation objectives for identified
ionizable organics or inorganics for the migration to groundwater
soil component portion of the groundwater ingestion exposure
route (based on the total amount of contaminants present in the soil
sample results and groundwater classification) are provided in
Appendix B, Tables C and D.
D) Values used to calculate the Tier 1 soil remediation objectives for
this exposure route are listed in Appendix B, Table F.
4)
Evaluation of the dermal contact with soil exposure route is not required
under Tier 1.
b)
Groundwater
1)
The Tier 1 groundwater remediation objectives for the direct ingestion of
groundwater component portion of the groundwater ingestion route are
listed in Appendix B, Table E.
92
2)
The Tier 1 groundwater remediation objectives for this exposure route are
given for Class I and Class II groundwaters, respectively.
3) The Class I groundwater remediation objectives set forth in Appendix B,
Table E shall be corrected for cumulative effect of mixtures of similar-
acting noncarcinogenic chemicals in accordance with the methodologies set
forth in either subsection (A) or (B), if more than one chemical listed in
Appendix A, Table E is detected at a site and if such chemicals affect the
same target organ (
i.e
., has the same critical effect as defined by the RfD):
A) Calculate the weighted average using the following equations:
W
ave =
x
CUO
x
CUO
x
CUO
x
CUO
x
x
x
a
x
a
1
2
3
1
2
3
+
+
+
+
K
where:
W
ave
= Weighted Average
x
1
through x
a
= Concentration of each individual contaminant at the
location of concern. Note that, depending on the
target organ/mode of action, the actual number of
contaminants will range from 2 to 14.
CUO
x
a
= A Tier 1 remediation objective each x
a
from
Appendix B, Table E.
ii) If the value of the weighted average calculated in
accordance with the equations above is less than or equal to
1.0, then the remediation objectives are met for those
chemicals.
ii) If the value of the weighted average calculated in
accordance with the equations above is greater than 1.0,
then additional remediation must be carried out until the
level of contaminants remaining in the remediated area have
a weighted average calculated in accordance with the
equation above less than or equal to one;
B) Divide each individual chemical's remediation objective by the
number of chemicals in that specific target organ group that were
detected at the site. Each of the contaminant concentrations at the
site is then compared to the remediation objectives that have been
adjusted to account for this potential additivity
93
Section 742.510
Tier 1 Remediation Objectives Tables
a)
Soil remediation objectives are listed in Appendix B, Tables A, B, C, and D.
1)
Appendix B, Table A is based upon residential property use.
A)
The first column to the right of the chemical name lists soil
remediation objectives for the soil ingestion exposure route.
B)
The second column lists the soil remediation objectives for the
inhalation exposure route.
C)
The third and fourth columns list soil remediation objectives for the
migration to groundwater soil component portionof the
groundwater ingestion exposure route for the respective classes of
groundwater:
i)
Class I groundwater; and
ii)
Class II groundwater.
D)
The final column lists is the Acceptable Detection Limit (ADL),
only where applicable.
2)
Appendix B, Table B is based upon industrial/commercial property use.
A)
The first and third columns to the right of the chemical name list the
soil remediation objectives for the soil ingestion exposure route
based on two receptor populations:
i)
Industrial/commercialpopulation; and
ii)
Construction workerpopulation.
B)
The second and fourth columns to the right of the chemical name
list the soil remediation objectives for the inhalation exposure route
based on two receptor populations:
i)
Industrial/commercialpopulation; and
ii)
Construction workerpopulation.
C)
The fifth and sixth columns to the right of the chemical name list
the soil remediation objectives for the migration to groundwater
94
soil component portionof the groundwater ingestion exposure route
based on TCLP analyses for two classes of groundwater:
i)
Class I groundwater; and
ii)
Class II groundwater.
3)
Appendix B, Tables C and D set forth pH specific soil remediation
objectives for inorganic and ionizing organic chemicals for the soil
component of the groundwater ingestion route.
A) Table C sets forth remediation objectives based on Class I
groundwater and Table D sets forth remediation objectives based
on Class II groundwater.
B) The first column in Tables C and D lists the chemical names.
C) The second through ninth columns to the right of the chemical
names list the pH based soil remediation objectives.
4)
For the inorganic chemicals listed in Appendix B, Tables A and B, the soil
component of the groundwater ingestion exposure route shall be evaluated
using TCLP (SW846 Method 1311) or SPLP (SW 846 Method 1312),
incorporated by reference at Section 742.210 unless a person chooses to
evaluate the soil component on the basis of the total amount of
contaminant in a soil sample result in accordance with subsection (a)(5) of
this Section.
53)
For those inorganic and ionizing organic chemicals listed in Appendix B,
Tables C and D, if a person elects to evaluate the migration to groundwater
portion soil component of the groundwater ingestion exposure route based
on the total amount of contaminant in a soil sample result (rather than
TCLP or SPLP analysis), the person shall determine the soil pH at the site
and then select the appropriate soil remediation objectives based on Class I
and Class II groundwaters using from Tables C and D, respectively. If the
soil pH is less than 4.5 or greater than 8.0, then Tables C and D cannot be
used.
46)
Unless one or more exposure routes are excluded from consideration under
Subpart C, the most stringent soil remediation objective of the exposure
routes (
i.e
., soil ingestion exposure route, inhalation exposure route, and
migration to groundwater soil component portionof the groundwater
ingestion exposure route) shall be compared to the concentrations of soil
contaminants of concern measured at the site. When using Appendix B,
Table B to select soil remediation objectives for the ingestion exposure
95
route and inhalation exposure route, the remediation objective shall be the
more stringent soil remediation objective of the industrial/commercial
populations and construction worker populations.
57)
Confirmation sample results may be averaged or soil samples may be
composited in accordance with Section 742.225.
68)
If a soil remediation objective for a chemical is less than the ADL, the ADL
shall serve as the soil remediation objective.
b)
Groundwater remediation objectives for the direct ingestion of groundwater
component portion of the groundwater ingestion exposure route are listed in
Appendix B, Table E. However, Appendix B, Table E must be corrected for
cumulative effect of mixtures of similar-acting noncarcinogenic chemicals as set
forth in Section 742.505(b)(3).
1)
The first column to the right of the chemical name lists groundwater
remediation objectives for Class I groundwater, and the second column
lists the groundwater remediation objectives for Class II groundwater.
2)
To use Appendix B, Table E of this Part, the Part 620 classification for
groundwater at the site shall be determined. The concentrations of
groundwater contaminants of concern at the site are compared to the
applicable Tier 1 groundwater remediation objectives for the direct
ingestion of groundwater component portionof the groundwater ingestion
exposure route in Appendix B, Table E. Appendix D describes the
procedures to be used in determining whether groundwater is Class II.
c)
For contaminants of concern not listed in Appendix B, Tables A, B, and E, a
person may request site-specific remediation objectives from the Agency or
propose site-specific remediation objectives in accordance with 35 Ill. Adm. Code
620, Subpart I of this Part, or both.
SUBPART F: TIER 2 GENERAL EVALUATION
Section 742.600
Tier 2 Overview Introduction
a)
Tier 2 remediation objectives are developed through the use of equations which
allow site-specific data to be used. (sSee Appendix C, Illustrations A and B). The
equations, identified in Appendix C, Tables A and C may be used to develop Tier 2
remediation objectives.
b)
Tier 2 evaluation is only required for contaminants of concern and corresponding
exposure routes (except where excluded from further consideration under Subpart
C) exceeding the Tier 1 remediation objectives. When conducting Tier 2
96
evaluations, the values used in the calculations must have the appropriate units of
measure as identified in Appendix C, Tables B and D.
c)
Any development of remediation objectives using site-specific information or
equations outside the Tier 2 framework shall be evaluated under Tier 3.
d)
Any development of a remediation objective under Tier 2 shall not use a target
hazard quotient greater than one at the point of human exposure or a target cancer
risk greater than 1 in 1,000,000 at the point of human exposure.
d e)
In conducting a Tier 2 evaluation, the following conditions shall be met:
1)
For each discrete sample, the total soil contaminant concentration of either
a single contaminant or multiple contaminants of concern shall not exceed
the attenuation capacity of the soil as provided in Section 742.215.
2)
Remediation objectives for noncarcinogenic compounds which affect the
same target organ, organ system or similar mode of action shall meet the
requirements of Section 742.720610
3)
The soil remediation objectives based on the inhalation and migration to
groundwater the soil component portionof the groundwater ingestion
exposure routes shall not exceed the soil saturation limit as provided in
Section 742.220.
e f)
If the calculated Tier 2 soil remediation objective for an applicable exposure route
is more stringent than the corresponding Tier 1 remediation objective, then the
Tier 1 remediation objective applies.
f g)
If the calculated Tier 2 soil remediation objective for an exposure route is more
stringent than the Tier 1 soil remediation objective(s) for the other exposure
routes, then the Tier 2 calculated soil remediation objective applies and Tier 2 soil
remediation objectives for the other exposure routes are not required.
g h)
If the calculated Tier 2 soil remediation objective is less stringent than one or more
of the soil remediation objectives for the remaining exposure routes, then the Tier
2 values are calculated for the remaining exposure route(s) and the most stringent
Tier 2 calculated value applies.
Section 742.605
Land Use
a)
Present and post-remediation land use is evaluated in a Tier 2 evaluation.
Acceptable exposure factors for the Tier 2 evaluation for residential,
industrial/commercial, and construction worker populations are provided in the far
right column of both Appendix C, Tables B and D. Use of exposure factors
97
different from those in Appendix C, Tables B and D must be approved by the
Agency as part of a Tier 3 evaluation.
b)
If a Tier 2 evaluation is based on an industrial/commercial property use, then:
1)
Construction worker populations shall also be evaluated; and
2)
Institutional controls are required in accordance with Subpart J.
Section 742.610 Chemicals with Cumulative Noncarcinogenic Effects
Appendix A, Table E lists the groups of chemicals from Appendix B, Tables A and B that have
remediation objectives based on noncarcinogenic toxicity and that affect the same target organ. If
more than one chemical detected at a site affects the same target organ (i.e., has the same critical
effect as defined by the RfD), the initially calculated remediation value for each chemical in the
group shall be corrected for cumulative effects by one of the following two methods:
a) Calculate the weighted average using the following equations:
W
ave =
x
CUO
x
CUO
x
CUO
x
CUO
x
x
x
a
x
a
1
2
3
1
2
3
+
+
+
+
K
where:
W
ave
= Weighted Average
x
1
through x
a
= Concentration of each individual contaminant at the
location of concern. Note that, depending on the
target organ/mode of action, the actual number of
contaminants will range from 2 to 14.
CUO
x
a
= A Tier 2 remediation objective must be developed
for each x
a
.
If the value of the weighted average calculated in accordance with the equations
above is less than or equal to 1.0, then the remediation objectives are met for those
chemicals.
If the value of the weighted average calculated in accordance with the equations
above is greater than 1.0, then additional remediation must be carried out until the
level of contaminants remaining in the remediated area have a weighted average
calculated in accordance with the equation above less than or equal to one;
b) Divide each individual chemical's remediation objective by the number of chemicals
in that specific target organ group that were detected at the site. Each of the
98
contaminant concentrations at the site is then compared to the remediation
objectives that have been adjusted to account for this potential additivity. For the
noncarcinogenic contaminants listed in Appendix A, Table E, a respective soil
remediation objective need be no lower than the respective value listed in
Appendix B, Tables A or B.
Section 742.615610 Chemical and Site Properties
a)
Physical and Chemical Properties of Contaminants
Tier 2 evaluations require information on the physical and chemical properties of
the contaminants of concern. The physical and chemical properties used in a Tier
2 evaluation are contained in Appendix C, Table E. If the site has contaminants
not included in this table, a person may request the Agency to provide the
applicable physical and chemical input values or may propose input values under
Subpart I. If a person proposes to apply values other than those in Appendix C,
Table E, or those provided by the Agency, the evaluation shall be considered under
Tier 3.
b)
Soil and Groundwater Parameters
1)
A Tier 2 evaluation requires examination of soil and groundwater
parameters. The parameters that may be varied, and the conditions under
which these parameters are determined as part of Tier 2, are summarized in
Appendix C, Tables B and D. If a person proposes to vary site-specific
parameters outside of the framework of these tables, the evaluation shall be
considered under Tier 3.
2)
To determine site-specific physical soil parameters, a minimum of one
boring per 0.5 acre of contamination shall be collected. This boring must
be deep enough to allow the collection of the required field measurements.
The site-specific physical soil parameters must be determined from the
portion of the boring representing the stratigraphic unit(s) being evaluated.
For example, if evaluating the migration to groundwatersoil component
portionof the groundwater ingestion exposure route, two samples from the
boring will be required:
A)
A sample of the predominant soil type for the vadose zone; and
B)
A sample of the predominant soil type for the saturated zone.
3)
A site-specific SSL dilution factor (used in developing soil remediation
objectives based upon the protection of groundwater) may be determined
by substituting site information in Equation S22 in Appendix C, Table A.
To make this demonstration, a minimum of three (3) monitoring wells shall
99
be used to determine the hydraulic gradient. As an alternative, the default
dilution factor value listed in Appendix C, Table B may be isused. If
monitoring wells are used to determine the hydraulic gradient, the soil
taken from the borings shall be visually inspected to ensure there are no
significant differences in the stratigraphy. If there are similar soil types in
the field, one boring shall be used to determine the site-specific physical
soil parameters. If there are significant differences, all of the borings shall
be evaluated before determining the site-specific physical soil parameters
for the site.
4)
Not all of the parameters identified in Appendix C, Tables B and D need to
be determined on a site-specific basis. A person may choose to collect
partial site-specific information and use default values as listed in Appendix
C, Tables B and D for the rest of the parameters.
5) Appendix D describes the procedures to be used in determining whether
groundwater is Class II.
SUBPART G: TIER 2 SOIL EVALUATION
Section 742.700
Tier 2 Soil Overview
a)
Tier 2 remediation objectives are developed through the use of models which allow
site-specific data to be considered. Appendix C, Tables A and C list equations that
shall be used under a Tier 2 evaluation to calculate soil remediation objectives
prescribed by SSL and RBCA models, respectively. (Ssee also Appendix C,
Illustration A).
b)
Appendix C, Table A lists equations that are used under the SSL model. (Ssee
also Appendix C, Illustration A). The SSL model has equations to evaluate the
following human exposure routes:
1)
Soil ingestion exposure route;
2)
Inhalation exposure route for:
A)
Volatiles;
B)
Fugitive dust; and
3)
Migration to groundwaterSoil component portionof the groundwater
ingestion exposure route.
c)
Evaluation of the dermal exposure route is not required under the SSL model.
100
d)
Appendix C, Table C lists equations that are used under the RBCA model. (Ssee
also Appendix C, Illustration A). The RBCA model has equations to evaluate
human exposure based on the following:
1)
The combined exposure routes of inhalation of vapors and particulates, soil
ingestion, and dermal contact with soil;
2)
The ambient vapor inhalation (outdoor) route from subsurface soils;
3)
Migration to groundwaterSoil component portionof the groundwater
ingestion route; and
4)
Groundwater ingestion exposure route.
e)
The equations in either Appendix C, Tables A or C may be used to calculate
remediation objectives for each contaminant of concern under Tier 2, if the
following requirements are met:
1)
The Tier 2 soil remediation objectives for the ingestion and inhalation
exposure routes shall use the applicable equations from the same approach
(i.e., SSL equations in Appendix C, Table C).
2)
The equations used to calculate soil remediation objectives for the
migration to groundwater soil component portionof the groundwater
ingestion exposure route are not dependent on the approach utilized to
calculate soil remediation objectives for the other exposure routes. For
example, it is acceptable to use the SSL equations for calculating Tier 2
soil remediation objectives for the ingestion and inhalation exposure routes,
and the RBCA equations for calculating Tier 2 soil remediation objectives
for the migration to groundwatersoil component portionof the groundwater
ingestion exposure route.
3)
Combining equations from Appendix C, Tables A and C to form a new
model is not allowed. In addition, Appendix C, Tables A and C must use
their own applicable parameters identified in Appendix C, Tables B and D,
respectively.
f)
In calculating soil remediation objectives for industrial/commercial property use,
applicable calculations shall be performed twice: once using industrial/commercial
population default values and once using construction worker population default
values. The more stringent soil remediation objectives derived from these
calculations must be used for further Tier 2 evaluations.
101
g)
Tier 2 data sheets provided by the Agency shall be used to present calculated Tier
2 remediation objectives, if required by the particular program for which
remediation is being performed.
h)
The RBCA equations which rely on the parameter Soil Water Sorption Coefficient
(k
s
) can only be used for ionizing organics and inorganics by substituting values for
k
s
from Appendix C, Tables I and J, respectively. This will also require the
determination of a site-specific value for soil pH.
Section 742.705
Parameters for Soil Remediation Objective Equations
a)
Appendix C, Tables B and D list the input parameters for the SSL and RBCA
equations, respectively. The first column lists each symbol as it is presented in the
equation. The next column defines the parameters. The third column shows the
units for the parameters. The fourth column identifies where information on the
parameters can be obtained (i.e., field measurement, applicable equation(s),
reference source, or default value). The last column identifies how the parameters
can be generated. A discussion of each parameter group follows.
b)
Default Values
Default values are numerical values specified for use in the Tier 2 equations. The
fourth column of Appendix C, Tables B and D denotes if the default values are
from the SSL model, RBCA model, or some other source. The last column of
Appendix C, Tables B and D lists the numerical values for the default values used
in the SSL and RBCA equations, respectively.
c)
Site-specific Information
Site-specific information is a parameter measured, obtained, or determined from
the site to calculate Tier 2 remediation objectives. The fourth column of Appendix
C, Tables B and D identifies those site-specific parameters that may require direct
field measurement. For some parameters, numerical default inputs have been
provided in the last column
of Appendix C, Tables B and D to substitute for site-
specific information. In some cases, information on the receptor or soil type is
required to select the applicable numerical default inputs. Site-specific information
includes:
1)
Physical soil parameters identified in Appendix C, Table F. The second
column identifies the location where the sample is to be collected.
Acceptable methods for measuring or calculating these soil parameters are
identified in the last column of Appendix C, Table F;
2)
Engineered barriers or institutional controlsInstitutional controls or
engineered barriers,which can affect the target cancer risk. pursuant to
102
Subparts J and K, describe applicable institutional controls and engineered
barriers under a Tier 2 evaluation.; and
3)
Land use classificationReceptor classification (i.e., residential,
industrial/commercial, and construction worker populations).
d)
Toxicological-specific Information
1)
Toxicological-specific information is used to calculate Tier 2 remediation
objectives for the following parameters if applicable:
A)
Oral Chronic Reference Dose (RfD
o
, expressed in mg/kg-d);
B)
Oral Subchronic Reference Dose (RfD
s
, expressed in mg/kg-d, shall
be used for construction worker remediation objective
calculations);
C)
Oral Slope Factor (SF
o
, expressed in (mg/kg-d)
-1
);
D)
Inhalation Unit Risk Factor (URF expressed in (ug/m
3
)
-1
);
E)
Inhalation Chronic Reference Concentration (RfC, expressed in
mg/m
3
);
F)
Inhalation Subchronic Reference Concentration (RfC
s
, expressed in
mg/m
3
, shall be used for construction worker remediation objective
calculations);
G)
Inhalation Chronic Reference Dose (RfD
i
, expressed in mg/kg-d);
H)
Inhalation Subchronic Reference Dose (RfD
is
, expressed in mg/kg-
d, shall be used for construction worker remediation objective
calculations); and
I)
Inhalation Slope Factor (SF
i
, expressed in (mg/kg-d)
-1
);
2)
Toxicological information can be obtained from IRIS, as incorporated by
reference in Section 742.210, or the program under which the remediation
is being performed.
e)
Chemical-specific Information
Chemical-specific information used to calculate Tier 2 remediation objectives is
listed in Appendix C, Table E.
103
f)
Calculations
Calculating numerical values for some parameters requires the use of equations
listed in Appendix C, Tables A or C.
The parameters that are calculated are listed
in Appendix C, Tables B and D.
Section 742.710
SSL Soil Equations
a)
This Section sets forth the equations and parameters used to develop Tier 2 soil
remediation objectives for the three exposure routes using the SSL approach.
b)
Soil Ingestion Exposure Route
1)
Equations S1 through S3 form the basis for calculating Tier 2 remediation
objectives for the soil ingestion exposure route using the SSL approach.
Equation S1 is used to calculate soil remediation objectives for
noncarcinogenic contaminants. Equations S2 and S3 are used to calculate
soil remediation objectives for carcinogenic contaminants for residential
populations and industrial/commercial and construction worker
populations, respectively.
2)
For Equations S1 through S3, the SSL default values cannot be modified
with site-specific information.
3)
For Equations S2 and S3, the only parameter that can be modified is the
target cancer risk. A target cancer risk of more than 1 in 1,000,000 may
be used if the applicable exposure routes have been managed through the
use of institutional controls. The remaining parameters in Equations S2
and S3 are default values, and the corresponding numerical values in
Appendix C, Table B must be used to calculate the Tier 2 SSL ingestion
exposure route remediation objectives.
c)
Inhalation Exposure Route
1)
Equations S4 through S16, S26, and S27 are used to calculate Tier 2 soil
remediation objectives for the inhalation exposure route using the SSL
approach. To address this exposure route, volatiles must be evaluated
separately from fugitive dust using their own equations set forth in
subsections (c)(2) and (c)(3) of this Section, respectively.
2)
Volatiles
A)
Equations S4 through S10 are used to calculate Tier 2 soil
remediation objectives for volatile contaminants based on the
inhalation exposure route. Equation S4 is used to calculate soil
104
remediation objectives for noncarcinogenic volatile contaminants in
soil for residential and industrial/commercial populations. Equation
S5 is used to calculate soil remediation objectives for
noncarcinogenic volatile contaminants in soil for construction
worker populations. Equation S6 is used to calculate soil
remediation objectives for carcinogenic volatile contaminants in soil
for residential and industrial/commercial populations. Equation S7
is used to calculate soil remediation objectives for carcinogenic
volatile contaminants in soil for construction worker populations.
Equations S8 through S10, S27, and S28 are used for calculating
numerical values for some of the parameters in Equations S4
through S7.
B)
For Equation S4, a numerical value for the Volatilization Factor
(VF) can be calculated in accordance with subsection (c)(2)(F) of
this Section. The remaining parameters in Equation S4 have either
SSL default values listed in Appendix C, Table B or toxicological-
specific information (i.e., RfC), which can be obtained from IRIS or
requested from the program under which the remediation is being
performed.
C)
For Equation S5, a numerical value for the Volatilization Factor
adjusted for Agitation (VF') can be calculated in accordance with
subsection (c)(2)(G) of this Section. The remaining parameters in
Equation S5 have either SSL default values listed in Appendix C,
Table B or toxicological-specific information (i.e., RfC), which can
be obtained from IRIS or requested from the program under which
the remediation is being performed.
D)
For Equation S6, a numerical value for VF can be calculated in
accordance with subsection (c)(2)(F) of this Section. The
remaining parameters in Equation S6 have either default values
listed in Appendix C, Table B or toxicological-specific information
(i.e., URF), which can be obtained from IRIS or requested from the
program under which the remediation is being performed.
E)
For Equation S7, a numerical value for VF' can be calculated in
accordance with subsection (c)(2)(G) of this Section. The
remaining parameters in Equation S7 have either default values
listed in Appendix C, Table B or toxicological-specific information
(i.e., URF), which can be obtained from IRIS or requested from the
program under which the remediation is being performed.
F)
The VF can be calculated for residential and commercial/industrial
industrial/commercial populations using one of the following
105
equations based on the information known about the contaminant
source and receptor population:
i)
Equation S8, in conjunction with Equation S10, is used to
calculate VF assuming an infinite source of contamination.
or
ii)
If the area and depth of the contaminant source are known
or can be estimated reliably, mass limit considerations may
be used to calculate VF using Equation S26.
G)
The VF' can be calculated for the construction worker populations
using one of the following equations based on the information
known about the contaminant source:
i)
Equation S9 is used to calculate VF' assuming an infinite
source of contamination. or
ii)
If the area and depth of the contaminant source are known
or can be estimated reliably, mass limit considerations may
be used to calculate VF' using Equation S27.
3)
Fugitive Dust
A)
Equations S11 through S16 are used to calculate Tier 2 soil
remediation objectives using the SSL fugitive dust model for the
inhalation exposure route. Equation S11 is used to calculate soil
remediation objectives for noncarcinogenic contaminants in fugitive
dust for residential and industrial/commercial populations.
Equation S12 is used to calculate soil remediation objectives for
noncarcinogenic contaminants in fugitive dust for construction
worker populations. Equation S13 is used to calculate soil
remediation objectives for carcinogenic contaminants in fugitive
dust for residential and industrial/commercial populations.
Equation S14 is used to calculate soil remediation objectives for
carcinogenic contaminants in fugitive dust for construction worker
populations. Equations S15 and S16 are used for calculating
numerical quantities for some of the parameters in Equations S11
through S14.
B)
For Equation S11, a numerical value can be calculated for the
Particulate Emission Factor (PEF) using Equation S15. This
equation relies on various input parameters from a variety of
sources. The remaining parameters in Equation S11 have either
SSL default values listed in Appendix C, Table B or toxicological-
106
specific information (i.e., RfC), which can be obtained from IRIS or
requested from the program under which the remediation is being
performed.
C)
For Equation S12, a numerical value for the Particulate Emission
Factor for Construction Worker (PEF') can be calculated using
Equation S16. The remaining parameters in Equation S12 have
either SSL default values listed in Appendix C, Table B or
toxicological-specific information (i.e., RfC), which can be obtained
from IRIS or requested from the program under which the
remediation is being performed.
D)
For Equation S13, a numerical value for PEF can be calculated
using Equation S15. The remaining parameters in Equation S13
have either default values listed in Appendix C, Table B or
toxicological-specific information (i.e., URF), which can be
obtained from IRIS or requested from the program under which the
remediation is being performed.
E)
For Equation S14, a numerical value for PEF' can be calculated
using Equation S16. The remaining parameters in Equation S14
have either default values listed in Appendix C, Table B or
toxicological-specific information (i.e., URF), which can be
obtained from IRIS or requested from the program under which the
remediation is being performed.
d)
Migration to GroundwaterSoil Component Portionof the Groundwater Ingestion
Exposure Route
The Tier 2 remediation objective for the migration to groundwater soil component
portionof the groundwater ingestion exposure route can be calculated using one of
the following equations based on the information known about the contaminant
source and receptor population:
1)
Equation S17 is used to calculate the remediation objective assuming an
infinite source of contamination.
A)
The numerical quantities for four parameters in Equation S17, the
Target Soil Leachate Concentration (C
w
), Soil-Water Partition
Coefficient (K
d
) for non-ionizing organics, Water-Filled Soil
Porosity (
θ
w
), and Air-Filled Soil Porosity (
θ
a
) are calculated using
Equations S18, S19, S20, and S21, respectively. Equations S22,
S23, S24, and S25 are also needed to calculate numerical values for
Equations S18 and S21. The pH-dependent K
d
values for ionizing
107
organics can be calculated using Equation S19 and the pH-
dependent K
oc
values in Appendix C, Table I.
B)
The remaining parameters in Equation S17 are Henry's Law
Constant (H'), a chemical specific value listed in Appendix C, Table
E and Dry Soil Bulk Density (
ρ
b
), a site-specific based value listed
in Appendix C, Table B.
C)
The default value for GW
obj
is the Tier 1 groundwater objective.
For chemicals for which there is no Tier 1 groundwater remediation
objective, the value for GW
obj
shall be the Health Advisory
concentration determined according to the procedures specified in
35 Ill. Adm. Code 620, Subpart F. As an alternative to using the
Tier 1 groundwater remediation objectives or Health Advisories, a
target risk for carcinogens greater than 1 in 1,000,000 may be used
to calculate GW
obj
using Equation S23, and a Target Hazard
Quotient greater than 1.0 may be used to calculate GW
obj
using the
procedures of Subpart I, if approved institutional controls are in
place as may be required in Subpart J. As an alternative to using
Tier 1 groundwater remediation objectives or Health Advisory
concentrations, GW
obj
may be developed using Equations R25 and
R26, if approved institutional controls are in place as required in
Subpart J.
2)
If the area and depth of the contaminant source are known or can be
estimated reliably, mass limit considerations may be used to calculate the
remediation objective for this exposure route using Equation S28. The
parameters in Equation S28 have default values listed in Appendix C, Table
B.
Section 742.715
RBCA Soil Equations
a)
This Section presents the RBCA model and describes the equations and
parameters used to develop Tier 2 soil remediation objectives.
b)
Ingestion, Inhalation, and Dermal Contact
1)
The two sets of equations in subsections (b)(2) and (b)(3) of this Section
shall be used to generate Tier 2 soil remediation objectives for the
combined ingestion, inhalation, and dermal contact with soil exposure
route.
2)
Combined Exposure Routes of Soil Ingestion, Inhalation of Vapors and
Particulates, and Dermal Contact with Soil
108
A)
Equations R1 and R2 form the basis for deriving Tier 2 remediation
objectives for the set of equations that evaluates the combined
exposure routes of soil ingestion, inhalation of vapors and
particulates, and dermal contact with soil using the RBCA
approach. Equation R1 is used to calculate soil remediation
objectives for carcinogenic contaminants. Equation R2 is used to
calculate soil remediation objectives for noncarcinogenic
contaminants. Soil remediation objectives for the ambient vapor
inhalation (outdoor) route from subsurface soils must also be
calculated in accordance with the procedures outlined in subsection
(b)(3) of this Section and compared to the values generated from
Equations R1 or R2. The smaller value (i.e., R1 and R2 compared
to R7 and R8, respectively) from these calculations is the Tier 2 soil
remediation objective for the combined exposure routes of soil
ingestion, inhalation, and dermal contact with soil.
B)
In Equation R1, numerical values are calculated for two
parameters:
i)
The volatilization factor for surficial soils (VF
ss
) using
Equations R3 and R4; and
ii)
The volatilization factor for subsurface soils regarding
particulates (VF
p
) using Equation R5.
C)
VF
ss
uses Equations R3 and R4 to derive a numerical value.
Equation R3 requires the use of Equation R6. Both equations must
be used to calculate the VF
ss
. The lowest calculated value from
these equations must be substituted into Equation R1.
D)
The remaining parameters in Equation R1 have either default values
listed in Appendix C, Table D or toxicological-specific information
(i.e., SF
o
, SF
i
), which can be obtained from IRIS or requested from
the program under which the remediation is being performed.
E)
For Equation R2, the parameters VF
ss
and VF
p
are calculated. The
remaining parameters in Equation R2 have either default values
listed in Appendix C, Table D or toxicological-specific information
(i.e., RfD
o
, RfD
i
) , which can be obtained from IRIS or requested
from the program under which the remediation is being performed.
F)
For chemicals other than inorganics which do not have default
values for the dermal absorption factor (RAF
d
) in Appendix C,
Table D, a dermal absorption factor of 0.5 shall be used for
109
Equations R1 and R2. For inorganics, dermal absorption may be
disregarded (i.e., RAF
d
=0).
3)
Ambient Vapor Inhalation (outdoor) route from Subsurface Soils (soil
below one meter)
A)
Equations R7 and R8 form the basis for deriving Tier 2 remediation
objectives for the ambient vapor inhalation (outdoor) route from
subsurface soils using the RBCA approach. Equation R7 is used to
calculate soil remediation objectives for carcinogenic contaminants.
Equation R8 is used to calculate soil remediation objectives for
noncarcinogenic contaminants.
B)
For Equation R7, the carcinogenic risk-based screening level for air
(RBSL
air
) and the volatilization factor for soils below one meter to
ambient air (VF
samb
) have numerical values that are calculated using
Equations R9 and R11, respectively. Both equations rely on input
parameters from a variety of sources.
C)
The noncarcinogenic risk-based screening level for air (RBSL
air
)
and the volatilization factor for soils below one meter to ambient air
(VF
samb
) in Equation R8 have numerical values that can be
calculated using Equations R10 and R11, respectively.
c)
Migration to GroundwaterSoil Component Portionof the Groundwater Ingestion
Exposure Route
1)
Equation R12 forms the basis for deriving Tier 2 remediation objectives for
the migration to groundwatersoil component portionof the groundwater
ingestion exposure route using the RBCA approach. The parameters,
groundwater at the source (GW
source
), and Leaching Factor (LF
sw
), have
numerical values that are calculated using Equations R13 and R14,
respectively.
2)
Equation R13 requires numerical values that are calculated using Equation
R15.
3)
Equation R14 requires numerical values that are calculated using Equations
R21, R22, and R24. For non-ionizing organics, the Soil Water Absorption
Sorption Coefficient (k
s
) shall be calculated using Equation R20. For
ionizing organics and inorganics, the values for k
s
are listed in Appendix C,
Tables I and J, respectively. The pH-dependent k
s
values for ionizing
organics can be calculated using Equation R20 and the pH-dependent K
oc
values in Appendix C, Table I. The remaining parameters in Equation R14
are field measurements or default values listed in Appendix C, Table D.
110
d)
The default value for GW
comp
is the Tier 1 groundwater remediation objective. For
chemicals for which there is no Tier 1 groundwater remediation objective, the
value for GW
comp
shall be the Health Advisory concentration determined according
to the procedures specified in 35 Ill. Adm. Code 620, Subpart F. As an alternative
to using the Tier 1 groundwater remediation objectives or Health Advisoryies
concentrations, a target risk for carcinogens greater than 1 in 1,000,000 may be
used to calculate GW
comp
using Equation R25, and a Target Hazard Quotient
greater than 1.0 may be used to calculate GW
comp
using the procedures of Subpart
I, GW
comp
may be developed
using Equations R25 and R26, if approved
institutional controls are in place as may be required in Subpart J.
Section 742.720 Chemicals with Cumulative Noncarcinogenic Effects
Appendix A, Table E lists the groups of chemicals from Appendix B, Tables A and B that have
remediation objectives based on noncarcinogenic toxicity and that affect the same target organ. If
more than one chemical detected at a site affects the same target organ (i.e., has the same critical
effect as defined by the RfD), the initially calculated remediation value for each chemical in the
group shall be corrected for cumulative effects by one of the following two methods:
a) Calculate the weighted average using the following equations:
W
ave =
x
CUO
x
CUO
x
CUO
x
CUO
x
x
x
a
x
a
1
2
3
1
2
3
+
+
+
+
K
where:
W
ave
= Weighted Average
x
1
through x
a
= Concentration of each individual contaminant at the
location of concern. Note that, depending on the
target organ/mode of action, the actual number of
contaminants will range from 2 to 14.
CUO
x
a
= A Tier 2 remediation objective must be developed
for each x
a
.
If the value of the weighted average calculated in accordance with the equations
above is less than or equal to 1.0, then the remediation objectives are met for those
chemicals.
If the value of the weighted average calculated in accordance with the equations
above is greater than 1.0, then additional remediation must be carried out until the
level of contaminants remaining in the remediated area have a weighted average
calculated in accordance with the equation above less than or equal to one;
111
b) Divide each individual chemical's remediation objective by the number of chemicals in that
specific target organ group that were detected at the site. Each of the contaminant concentrations
at the site is then compared to the remediation objectives that have been adjusted to account for
this potential additivity. For the noncarcinogenic contaminants listed in Appendix A, Table E, a
respective soil remediation objective need be no lower than the respective value listed in Appendix
B, Tables A or B.
SUBPART H: TIER 2 GROUNDWATER EVALUATION
Section 742.800
Tier 2 Groundwater Overview General
If the contaminant concentrations in the groundwater exceed
the applicable Tier 1 remediation
objectives, a person has the following options:
a)
Demonstrate that the groundwater ingestion exposure route is excluded from
consideration pursuant to Subpart C;
b)
Demonstrate that the groundwater contamination is
at or below area background
concentrations in accordance with Subpart D
and, if necessary, an institutional
control restricting usage of the groundwater is in place in accordance with Subpart
J;
c)
Remediate to Tier 1 remediation objectives;
d)
Develop Propose and obtain approval of Tier 2 groundwater remediation
objectives in accordance with Section 742.805 and remediate to that level, if
necessary;
e)
Conduct a Tier 3 evaluation in accordance with Subpart I; or
f)
Obtain approval from the Board to:
1)
Reclassify the groundwater pursuant to 35 Ill. Adm. Code 620.260;
or
2)
Use an adjusted standard pursuant to Section 28.1 of the Act. (415 ILCS
5/28.1).
Section 742.805
Tier 2 Groundwater Remediation Objectives
a)
To develop a groundwater remediation objective under this Section that exceeds
the applicable Tier 1 groundwater remediation objective, a person may request
approval from the Agency if the person has performed the following:
112
1)
Identified the horizontal and vertical extent of groundwater for which the
Tier 2 groundwater remediation objective is sought;
2)
Taken corrective action, to the maximum extent practicable to remove any
free product;
3)
Using Equation R26 in accordance with Section 742.810, demonstrated
that the concentration of any contaminant of concern in groundwater will
meet:
A)
The applicable Tier 1 groundwater remediation objective at the
point of human exposure; or
B)
For any contaminant of concern for which there is no Tier 1
groundwater remediation objective, the Health Advisory
concentration determined according to the procedures specified in
35 Ill. Adm. Code 620, Subpart F at the point of human exposure.
A person may request the Agency to provide these concentrations
or may propose these concentrations under Subpart I;.
4)
Using Equation R26 in accordance with Section 742.810, demonstrated
that the concentration of any contaminant of concern in groundwater
within the minimum or designated maximum setback zone of an existing
potable water supply well will meet the applicable Tier 1 groundwater
remediation objective or if there is no Tier 1 groundwater remediation
objective, the Health Advisory concentration;
5)
Using Equation R26 in accordance with Section 742.810, demonstrated
that the concentration of any contaminant of concern in groundwater
discharging into a surface water will meet the applicable surface water
quality standard under 35 Ill. Adm. Code 302;
6)
Demonstrated that the source of the release is not located within the
minimum or designated maximum setback zone of potable water supply
well nor or within a regulated recharge area of an existing potable water
supply well; and
7)
If the selected corrective action includes an engineered barrier as set forth
in Subpart K to minimize migration of contaminant of concern from the soil
to the groundwater, demonstrated that the engineered barrier will remain in
place for post-remediation land use through an institutional control as set
forth in Subpart J.
113
b)
A groundwater remediation objective that exceeds the water solubility of that
chemical (refer to Appendix C, Table E for solubility values) is not allowed.
c) Groundwater remediation objectives for chemicals which affect the same target
organ, organ system or similar mode of action shall meet the requirements of
Section 742.505(b)(3). Contaminants of concern for which a Tier 1 or Tier 3
remediation objective has been developed shall be included in any mixture of
similar-acting substances under consideration in Tier 2.
Section 742.810
Calculations to Predict Impacts from Remaining Groundwater Contamination
a)
Equation R26 predicts the contaminant concentration along the centerline of a
plume emanating from a vertical planar source in the aquifer (dimensions S
w
wide
and S
d
deep). This model accounts for both three-dimensional dispersion (x is the
direction of groundwater flow, y is the other horizontal direction, and z is the
vertical direction) and biodegradation.
1)
The parameters in this equation are:
A)
X =
distance from the planar source to the location of
concern, along the centerline of the plume (i.e., y=0,
z=0)
B)
C
(x)
=
the concentration of the contaminant at a distance X
from the source, along the centerline of the plume
C)
C
(source)
=
the greatest potential concentration of the contaminant
of concern in the groundwater at the source of the
contamination, based on the concentrations of
contaminants in groundwater due to the release and the
projected concentration of the contaminant migrating
from the soil to the groundwater. As indicated above,
the model assumes a planar source discharging
groundwater at a concentration equal to C
(source)
D)
α
x
=
dispersivity in the x direction (i.e., Equation R16)
E)
α
y
=
dispersivity in the y direction (i.e., Equation R17)
F)
α
z
=
dispersivity in the z direction (i.e., Equation R18)
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G)
U =
specific discharge (i.e., actual groundwater flow velocity
through a porous medium; takes into account the fact
that the groundwater actually flows only through the
pores of the subsurface materials), where the aquifer
hydraulic conductivity (Kk), the infiltration rate (I), the
hydraulic gradient (i), and the total soil porosity (
θ
T
)
must be known (i.e., Equation R19).
H)
λ
=
first order degradation constant obtained from Appendix
C, Table E or from measured groundwater data.
I)
S
w
=
width of planar source in the y direction
J)
S
d
=
depth of planar source in the z direction
2)
The following
parameters are determined through field measurements: U,
Kk, I i,
θ
T
, S
w
, S
d
.
A)
The determination of values for U, Kk, I i, and
θ
T
can be obtained
through the appropriate laboratory and field techniques;
B)
From the immediate down-gradient edge of the source of the
groundwater contamination values for S
w
and S
d
shall be
determined. S
w
is defined as the width of groundwater at the
source which exceeds the Tier 1 groundwater remediation
objective. S
d
is defined as the depth of groundwater at the source
which exceeds the Tier 1 groundwater remediation objective; and .
C)
Total soil porosity can also be calculated using Equation R23.
3)
The value of C
(source)
equals the greatest concentration of the contaminant in
the groundwater at the source of the contamination.
b)
Once values are obtained for all the input parameters identified in subsection (a) of
this Section, the contaminant concentration along the centerline of the plume at a
distance X from the source shall be calculated such that that distance from the
down-gradient edge of the source of the contamination at the site to the point
where the contaminant concentration is equal to the Tier 1 groundwater
remediation objective or Health Advisory concentration.
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1)
To demonstrate that no existing potable water supply well is adversely
impacted, X shall be the distance from the down-gradient edge of the
source of the contamination at the site to the nearest water supply well.
This calculation must show that the contaminant in the groundwater at this
location (C
(x)
), does not exceed the applicable Tier 1 groundwater
remediation objective or Health Advisory concentration.If there are any
potable water supply wells located within the calculated distance X, then
the Tier 1 groundwater remediation objective or Health Advisory
concentration shall be met at the edge of the minimum or designated
maximum setback zone of the nearest potable water supply well down-
gradient of the source. If no potable water supply wells exist within the
calculated distance X, then it can be determined that no existing potable
water supply wells are adversely impacted.
2)
To demonstrate that no surface water is adversely impacted, X shall be the
distance from the down-gradient edge of the source of the contamination at
the site to the nearest surface water body. This calculation must show that
the contaminant in the groundwater at this location (C
(x)
), does not exceed
the applicable surface water quality standard.
SUBPART I: TIER 3 EVALUATION
Section 742.900
Tier 3 Overview Introduction
a)
Tier 3 sets forth a flexible framework to develop remediation objectives outside of
the requirements of Tiers 1 and 2. Although Tier 1 evaluations and Tier 2
evaluations are not prerequisites to conduct Tier 3 evaluations, data from Tier 1
and Tier 2 can assist in developing remediation objectives under a Tier 3
evaluation.
b)
The level of detail required to adequately characterize a site depends on the
particular use of Tier 3. Tier 3 can require additional investigative efforts beyond
those described in Tier 2 to characterize the physical setting of the site. However,
in situations where remedial efforts have simply reached a physical obstruction
(e.g., a building), additional investigation may not be necessary for a Tier 3
submittal.
c)
Situations that can be considered for a Tier 3 evaluation include, but are not
limited to:
1)
Modification of parameters not allowed under Tier 2 (e.g., a target hazard
quotient greater than 1 is requested) ;
2)
Use of models different from those used in Tier 2;
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3)
Use of additional site data to improve or confirm predictions of exposed
receptors to contaminants of concern;
4)
Analysis of site-specific risks using formal risk assessment, probabilistic
data analysis, and sophisticated fate and transport models (e.g., requesting
a target hazard quotient greater than 1 or a target cancer risk greater than 1
in 1,000,000) ;
5)
Requests for site-specific remediation objectives because an "common
sense" assessment indicates further remediation is not practical (e.g., the
remaining contamination is under a structure such as a permanent building);
6)
Incomplete human exposure pathway(s) not excluded under Subpart C;
7)
Use of toxicological-specific information not available from the sources
listed in Tier 2; and
8)
Land uses which are substantially different from the assumed residential or
industrial/commercial property uses of a site (e.g., a s site will be used for
recreation in the future and cannot be evaluated in Tiers 1 or 2).
9)
Requests for site-specific remediation objectives which exceed Tier 1
groundwater remediation objectives so long as the following is
demonstrated:
A) TO THE EXTENT PRACTICAL, THE EXCEEDANCE OF THE
GROUNDWATER QUALITY STANDARD HAS BEEN
MINIMIZED AND BENEFICIAL USE APPROPRIATE TO THE
GROUNDWATER THAT WAS IMPACTED HAS BEEN
RETURNED; AND
B) ANY THREAT TO HUMAN HEALTH OR THE ENVIRONMENT
HAS BEEN MINIMIZED. (Section 58.5(D)(4)(A))
d)
For requests of a target cancer risk ranging between 1 in 1,000,000 and 1 in
10,000 at the point of human exposure or a target hazard quotient greater than 1 at
the point of human exposure, the requirements of Section 742.915 shall be
followed. Requests for a target cancer risk exceeding 1 in 10,000 at the point of
human exposure are not allowed.
de)
Requests for approval of a Tier 3 evaluation must be submitted to the Agency for
review under the specific program under which remediation is performed. When
reviewing a submittal under Tier 3, the Agency shall consider WHETHER THE
INTERPRETATIONS AND CONCLUSIONS REACHED ARE SUPPORTED
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BY THE INFORMATION GATHERED. (Section 58.7(e)(1) of the Act) The
Agency shall approve a Tier 3 evaluation if the person submits the information
required under this Part and establishes through such information that public health
is protected and that specified risks to human health and the environment have
been minimized.
Section 742.905
Modifications of Parameters
Any proposed changes to Tier 2 parameters which are not provided for in Tier 2 shall be
submitted to the Agency for review and approval.
A submittal under this Section shall include the
following information:
a)
The justification for the modification; and
b)
The technical and mathematical basis for the modification.
Section 742.910
Alternative Models
Any proposals for the use of models other than those specified in Tier 2 shall be submitted to the
Agency for review and approval. A submittal under this Section shall include the following
information:
a)
Physical and chemical properties of contaminants of concern;
b)
Contaminant movement properties;
c)
Contaminant availability to receptors;
d)
Receptor exposure to the contaminants of concern;
e)
Mathematical and technical justification for the model proposed;
f)
A licensed copy of the model, if the Agency does not have a licensed copy of the
model currently available for use; and
g)
Demonstration that the models were correctly applied.
Section 742.915
Formal Risk Assessments
A comprehensive site-specific risk assessment shall demonstrate that contaminants of concern at a
site do not pose a significant risk to any human receptor. All site-specific risk assessments shall
be submitted to the Agency for review and approval. A submittal under this Section shall address
the following factors:
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a)
Whether the risk assessment procedure used is nationally recognized and accepted
including, but not limited to, those procedures incorporated by reference in Section
742.210;
b)
Whether the site-specific data reflect actual site conditions;
c)
The adequacy of the investigation of present and post-remediation exposure routes
and risks to receptors identified at the site;
d)
The appropriateness of the sampling and analysis;
e)
The adequacy and appropriateness of toxicity information;
f)
The extent of contamination; and
g)
Whether the calculations were accurately performed; and.
h) Proposals seeking to modify the target risk consistent with Section 742.900(d)
shall address the following factors:
1) the presence of sensitive populations;
2) the number of receptors potentially impacted;
3) the duration of risk at the differing target levels; and
4) the characteristics of the chemical of concern.
Section 742.920
Impractical Remediation
Any request for site-specific remediation objectives due to impracticality of remediation shall be
submitted to the Agency for review and approval. A submittal under this Section shall include the
following information:
a)
The reason(s) why the remediation is impractical;
b)
The extent of contamination;
c)
Geology, including soil types;
d)
The potential impact to groundwater;
e)
Results and locations of sampling events;
f)
Map of the area, including all utilities and structures; and
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g)
Present and post-remediation uses of the area of contamination, including human
receptors at risk.
Section 742.925
Exposure Routes
Technical information may demonstrate that there is no actual or potential impact of contaminants
of concern to receptors from a particular exposure route. In these instances, a demonstration
excluding an exposure route shall be submitted to the Agency for review and approval. A
submittal under this Section shall include the following information:
a)
A description of the route evaluated;
b)
Technical support including a discussion of the natural or man-made barriers to
exposure through that route, calculations, and modeling results;
c)
Physical and chemical properties of contaminants of concern;
d)
Contaminant migration properties;
e)
Description of the site and physical site characteristics; and
f)
Discussion of the result and possibility of the route becoming active in the future.
Section 742.930
Derivation of Toxicological Data
If toxicological-specific information is not available for one or more contaminants of concern
from the sources incorporated by reference in Section 742.210, the derivations of toxicological-
specific information shall be submitted for Agency review and approval.
Section 742.935 Agricultural Uses and Ecological Receptors (Reserved)
SUBPART J: INSTITUTIONAL CONTROLS
Section 742.1000
Institutional ControlsGeneral
a)
Any person who develops remediation objectives under this Part based on an
industrial/commercial property use or based on engineered barriers under Subpart
K shall meet the requirements of this Subpart relative to institutional controls.
Institutional controls in accordance with this Subpart must be in place placed on
the property when remediation objectives are based on any of the following
assumptions:
1)
Industrial/Commercial property use;
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2)
Target cancer risk greater than 1 in 1,000,000;
3)
Target hazard quotient greater than 1;
4)
Engineered barrier(s); or
5)
Any combination of the above.The point of human exposure is located at a
place other than at the source;
6)
Exclusion of exposure routes under Subpart C; or
5 7)
Any combination of the above.
b)
The Agency shall not approve any remediation objective under this Part that is
based on the use of institutional controls unless the person has proposed
institutional controls meeting the requirements of this Subpart and the
requirements of the specific program under which the institutional control is
proposed. A proposal for approval of institutional controls shall provide
identification of the selected institutional controls from among the types
recognized in this Subpart.
c)
The following instruments types of may be institutional controls, subject to the
requirements of this Subpart J and the requirements of the specific program under
which the institutional control is proposed are recognized under this Subpart:
1)
No Further Remediation Letters;
2)
Restrictive covenants and deed restrictions;
3)
Negative easements;
4)
Ordinances adopted and administered by a unit of local government; and
5)
Agreements between a property owner and a highway authority with
respect to any contamination remaining under highways.
BOARD NOTE: Definition in the Illinois Highway Code for “highway authority”,
“highway”, and “right of way” are applicable to this Part.
d) An institutional control is transferred with the property.
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Section 742.1005
No Further Remediation Letters
a)
A No Further Remediation Letter issued by the Agency under Part 732 or 742 may
be used as an institutional control under this Part if the requirements of subsection
(b) of this Section are metand the Agency has determined that no further
remediation is required as to the property(ies) to which the letter is to apply.
b)
A request for approval of a No Further Remediation Letter as an institutional
control shall follow shall meet the requirements applicable to the remediation
specific program under which the remediation is performed.
c) The recipient of the letter shall submit the letter to the Office of the Recorder or
the Registrar of Titles of the county in which the site is located within 45 days of
receipt of the letter in such a manner that it forms a permanent part of the chain of
title for the site. Proper recording of the "No Further Remediation" letter shall
consist of adding the letter and an Environmental Notice form to other public
documents that would normally be examined during a title search.
d) A "No Further Remediation" letter shall not become effective until officially
recorded in accordance with subsection (c) of this Section. The recipient of the
letter shall obtain and submit to the Agency a copy of the letter demonstrating that
it has been recorded.
e) At no time shall any site for which land use has been restricted under a "No
Further Remediation" letter be used in a manner inconsistent with such land use
limitation unless further investigation or remedial action has been conducted that
documents the attainment of objectives appropriate for the new land use and a new
letter is obtained and recorded in accordance with subsection (c) of this Section.
f) Violation of the terms of a No Further Remediation Letter shall be grounds for
voidance of the Letter and the Agency's "No Further Remediation" determination
in accordance with the procedures applicable to the remediation program under
which the remediation is performed.
Section 742.1010
Restrictive Covenants, Deed Restrictions, and Negative Easements
a)
A restrictive covenant, deed restriction, or negative easement may be used as an
institutional control under this Part if the requirements of this Section are met and
the Agency has determined that " no further remediation" is required as to the
property(ies) to which the institutional control is to apply.
b)
A request for approval of a restrictive covenant, deed restriction, or negative
easement as an acceptable institutional control, shall provide the following:
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1)
A copy of the restrictive covenant, deed restriction, or negative easement
in the form it will be recorded with the Office of the Recorder or Registrar
of Titles in the county where the site is located. The restrictive covenant,
deed restriction, or negative easement shall reference or incorporate the
terms of the “No Further Remediation determination so as to require any
current owners and all successors in interest to meet the requirements of
the "No Further Remediation" determination as a condition of use of the
property;
2)
A scaled map showing the horizontal extent of contamination above the
applicable remediation objectives;
3)
Information showing the concentration of contaminants of concern in
which the applicable remediation objectives are exceeded;
4)
A scaled map showing the legal boundaries of all properties under which
contamination is located that exceeds the applicable remediation objectives
and which are subject to the restrictive covenant, deed restriction, or
negative easementsubject to the restrictive covenant, deed restriction, or
negative easement under which contamination is located that exceeds the
applicable remediation objectives;
5)
Information identifying the current owner(s) of each property identified in
subsection (b)(4) of this Section; and
6)
Authorization by the current owner(s), or person authorized by law to act
on behalf of the owner, of each property identified in subsection (b)(5) of
this Section to record the restrictive covenant or deed restriction.
c)
Any restrictive covenant, deed restriction, or negative easement approved by the
Agency pursuant to this Section shall be recorded in the Office of the Recorder or
Registrar of Titles of the county in which the site is located together with the
instrument memorializing the Agency’s no further remediation determination
pursuant to the specific program within 45 days after receipt of the Agency’s no
further remediation determination.Any restrictive covenant, deed restriction, or
negative easement approved by the Agency pursuant to this Part shall be recorded
with the "No Further Remediation" determination in the Office of the Recorder or
the Registrar of Titles of the county in which the site is located within 45 days of
receipt of the Agency approval in accordance with Section 742.1005(c)
d)
An institutional control approved under this Section shall not become effective
until officially recorded in accordance with subsection (c) of this Section. The
person receiving the approval shall obtain and submit to the Agency within 30 days
after recording a copy of the institutional control demonstrating that is it has been
recorded.
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e)
At no time shall any site for which land use has been restricted under an
institutional control approved under this Section be used in a manner inconsistent
with such land use limitation unless further investigation or remedial action has
been conducted that documents the attainment of remediation objectives
appropriate for such land use and a new institutional control, if necessary, is
approved and recorded in accordance with subsection (c) of this Section.
f)
Violation of the terms of an institutional control approved under this Section shall
be grounds for voidance of the institutional control and the instrument
memorializing the Agency's "Nno Ffurther Rremediation" determination pursuant
to Section 58.10 of Act.
Section 742.1015
Ordinances
a)
An ordinance adopted by a unit of local government that effectively prohibits the
installation of potable water supply wells (and the use of such wells) use of
groundwater as a potable supply of water, except at points of withdrawal by the
unit of local government, may be used as an institutional control to meet the
requirements of Sections 742.320(d) or 742.805(a)(3) if the requirements of this
Section are met. Ordinances prohibiting the installation of potable water supply
wells (and the use of such wells) that do not expressly prohibit the installation of
potable water supply wells (and the use of such wells) by units of local government
may be acceptable as institutional controls if the requirements of this Section are
met and a Memorandum of Understanding (MOU) is entered into under subsection
(i) of this Section.
b)
A request for approval of a local ordinance as an institutional control shall provide
the following:
1)
A copy of the ordinance restricting groundwater use certified by an official
of the unit of local government in which the site is located, that it is the
latest, most current copy of the ordinance, unless the Agency and the unit
of local government have entered an agreement under subsection (i) of this
Section, in which case the request may alternatively reference the
Memorandum of Understanding (MOU). The ordinance must demonstrate
that potable use of groundwater from potable water supply wells is
prohibited;
2)
A scaled map(s) delineating the areal extent of groundwater contamination
(measured or modeled) above the applicable remediation objectives;
3)
Information showing the concentration of contaminants of concern in
which the applicable remediation objectives are exceeded;
124
4)
A scaled map delineating the boundaries of all properties under which
groundwater is located which exceeds the applicable groundwater
remediation objectives;
5)
Information identifying the current owner(s) of each property identified in
subsection (b)(4) of this Section; and
6)
A copy of the proposed submission of the information to the current
owners identified in subsection (b)(5) of this Section of the information
required in subsections (b)(1) through (b)(5) of this Section and proof that
the notification required in subsection (c) of this Section has been
submitted.
c)
Each of the property owners identified in subsection (b)(5) of this Section and the
unit of local government must receive written notification from the party desiring
to use the institutional control that groundwater remediation objectives have been
approved by the Agency. Written proof of this notification shall be submitted to
the Agency within 45 days from the date of the instrument memorializing the
Agency’s “Nno Ffurther Rremediation” Letter or determination. The notification
shall include:
1)
The name and address of the unit of local government;
2)
The citation to the ordinance;
3)
A description of the property being sent notice by adequate legal
description or by reference to a plat showing the boundaries;
4)
A statement that the ordinance restricting groundwater use has been used
by the Agency in reviewing a request for a groundwater remediation
objective;
5)
A statement as to the nature of the release and response action with the site
name, address, and Agency site number or Illinois inventory identification
number; and
6)
A statement as to where more information may be obtained regarding the
ordinance.
d)
Unless the Agency and the unit of local government have entered into a MOUan
agreement under subsection (i) of this Section, the current owner or successors in
interest of a site who have received approval of use of an ordinance as an
institutional control under this Section shall:
125
1)
Monitor activities of the unit of local government relative to variance
requests or changes in the ordinance relative to the use of potable
groundwater at properties identified in subsection (b)(4) of this Section;
and
2)
Notify the Agency of any approved variance requests or ordinance changes
within thirty (30) days after the date such action has been approved.
e)
The information required in subsections (b)(1) through (b)(6) of this Section and
the Agency letter approving the groundwater remediation objective shall be
submitted to the unit of local government. Proof that the information has been
filed with the unit of local government shall be provided to the Agency.
f)
Any ordinance or MOU used as an institutional control pursuant to this Section
shall be recorded in the Office of the Recorder or Registrar of Titles of the county
in which the site is located together with the instrument memorializing the
Agency’s no further remediation determination pursuant to the specific program
within 45 days after receipt of the Agency’s no further remediation
determinationUnless the Agency and the unit of local government have entered an
agreement under subsection (i) of this Section, a site owner who has received
approval of use of an ordinance as an institutional control under this Section shall
record as an institutional control under Section 742.1005 or Section 742.1010, as
applicable, the site owner's duties under subsection (d) of this Section to monitor
activities of the unit of local government.
g)
An institutional control approved under this Section shall not become effective
until the site owner's duties under subsection (d) of this Section are officially
recorded in accordance with subsection (f) of this Section. The person receiving
the approval shall obtain and submit to the Agency within 30 days after recording a
copy of the institutional control demonstrating that it has been recorded.
h)
The following shall be grounds for voidance of the ordinance as an institutional
control and the instrument memorializing the Agency's “Nno Ffurther
Rremediation" determination:
1)
Modification of the ordinance by the unit of local government to allow
potable use of groundwater;
2)
Approval of a site-specific request, such as a variance, to allow potable use
of groundwater at a site identified in subsection (b)(4) of this Section; or
and
3)
Violation of the terms of an institutional control recorded under Section
742.1005 or Section 742.1010.
126
i)
The Agency and a unit of local government may enter into a memorandum of
understanding(MOU) under this Section if the unit of local government has
adopted an ordinance satisfying subsection (a) of this Section that effectively
prohibits the use of groundwater as a potable supply of water, except at points of
withdrawal by the unit of local government, and if the requirements of this
subsection are met. The MOU shall include the following:
1)
Identification of the authority of the unit of local government to enter the
MOU;
2)
Identification of the legal boundaries, or equivalent, under which the
ordinance is applicable;
3)
A certified copy of the ordinance;
4)
A commitment by the unit of local government to notify the Agency of any
variance requests or proposed ordinance changes at least thirty (30) days
prior to the date the local government is scheduled to take action on the
request or proposed change; and
5)
A commitment by the unit of local government to maintain a registry of all
sites within the unit of local government that have received "Nno Ffurther
Rremediation" determinations pursuant to specific programsunder this Part;
and.
6)
If the ordinance does not expressly prohibit the installation of potable water
supply wells (and the use of such wells) by units of local government, a
commitment by the unit of local government:
A)
To review the registry of sites established under subsection (i)(5) of
this Section prior to siting potable water supply wells within the
area covered by the ordinance;
B)
To determine whether the potential source of potable water may be
or has been affected by contamination left in place at those sites;
and
C)
To take whatever steps are necessary to ensure that the potential
source of potable water is protected from the contamination or
treated before it is used as a potable water supply.
Section 742.1020
Highway Authority Agreements
a)
An agreement with a highway authority may be used as an institutional control
where the requirements of this Section are met and the Agency has determined that
127
“no further remediation” is required as to the property(ies) to which the agreement
is to apply.
b)
As part of the agreement the highway authority shall agree to:
1)
Prohibit the use of groundwater under the highway right of way that is
contaminated above residential Tier 1 remediation objectives from the
release as a potable supply of water.
2)
Limit access to soil contamination under the highway right of way that is
contaminated above residential Tier 1 remediation objectives from the
release. Access to soil contamination may be allowed if, during and after
any access, public health and the environment are protected.
c)
A request for approval of an agreement as an institutional control shall provide the
following:
1)
A copy of the agreement executed by the highway authority and the owner
of the property from which the release occurred;
2)
A scaled map delineating the areal extent of soil and groundwater
contamination above the applicable Tier 1 remediation objectives;
3)
Information showing the concentration of contaminants of concern within
the zone in which the applicable Tier 1 remediation objectives are
exceeded;
4)
A stipulation of the information required by subsection (b) of this Section
in the agreement if it is not practical to obtain the information by sampling
the highway right-of-way; and
5)
Information identifying the current fee owner of the highway right-of-way
and highway authority having jurisdiction.
d)
Violation of the terms of an Agreement approved by the Agency as an institutional
control under this Section shall be grounds for voidance of the Agreement as an
institutional control and the instrument memorializing the Agency's “Nno Ffurther
Rremediation" determination.
SUBPART K: ENGINEERED BARRIERS
Section 742.1100
Engineered BarriersGeneral
128
a)
Any person who develops remediation objectives under this Part based on
engineered barriers shall meet the requirements of this Subpart and the
requirements of Subpart J relative to institutional controls.
b)
The Agency shall not approve any remediation objective under this Part that is
based on the use of engineered barriers unless the person has proposed engineered
barriers meeting the requirements of this Subpart.
c)
The use of engineered barriers can be recognized in calculating remediation
objectives only if the engineered barriers are intended for use as part of the final
corrective action.
d)
Any "Nno Ffurther Rremediation" determination based upon the use of engineered
barriers shall require effective maintenance of the engineered barrier. The
maintenance requirements shall be included in an institutional control under
Subpart J. and are to be maintained by the owner of the site. This responsibility
shall be transferable with the property. This institutional control shall address
provisions for temporary breaches of the barrier by requiring the following if
intrusive construction work is to be performed in which the engineered barrier is to
be temporarily breached:
1)
The construction workers shall be notified by the site owner/operator in
advance of intrusive activities. Such notification shall enumerate the
contaminant of concern known to be present; and
2)
The site owner/operator shall require construction workers to implement
protective measures consistent with good industrial hygiene practice.
e)
Failure to maintain an engineered barrier in accordance with the "Nno Ffurther
Rremediation" determination shall be grounds for voidance of theat determination
and the instrument memorializing the Agency’s no further remediation
determination.
Section 742.1105
Engineered Barrier Requirements
a)
Natural attenuation, access controls, and point of use treatment shall not be
considered engineered barriers. Engineered barriers may not be used to prevent
direct human exposure to groundwater without the use of institutional controls.
b)
For purposes of determining remediation objectives under Tier 1, engineered
barriers are not recognized.
c)
The following engineered barriers are recognized for purposes of calculating
remediation objectives that exceed residential remediation objectives:
129
1)
For the migration to groundwatersoil component portionof the
groundwater ingestion exposure route, the following engineered barriers
are recognized:
A)
Caps, covering the contaminated media, constructed of compacted
clay, asphalt, concrete or other material approved by the Agency;
and
B)
Permanent structures such as buildings and highways.
2)
For the soil ingestion exposure route, the following engineered barriers are
recognized:
A)
Caps, covering the contaminated media, constructed of compacted
clay, asphalt, concrete, or other material approved by the Agency;
B)
Permanent structures such as buildings and highways; and
C)
Clean soil, covering the contaminated media, that is a minimum of
one (1) meter 3 feet in depth.
3)
For the inhalation exposure route, the following engineered barriers are
recognized:
A)
Caps, covering the contaminated media, constructed of compacted
clay, asphalt, concrete, or other material approved by the Agency;
and
B)
Permanent structures such as buildings and highways. ; and
C)
Clean soil covering the contaminated media, that is a minimum of
ten (10) feet in depth and not within ten (10) feet of any manmade
pathway.
4)
For the ingestion of groundwater exposure route, the following engineered
barriers are recognized:
A)
Slurry walls; and
B)
Hydraulic control of groundwater.
d)
Unless otherwise prohibited under Section 742.1100, any other type of engineered
barrier may be proposed if it will be as effective as the options listed in subsection (c)
of this Section.
130
Section 742.APPENDIX A:
General
TABLE A:
Soil Saturation Limits (C
sat
) for Chemicals Whose Melting Point is Less than 30
°
°
C.
CAS No.
Chemical Name
C
sat
(mg/kg)
67-64-1
Acetone
100,000
71-43-2
Benzene
870
111-44-4
Bis(2-chloroethyl)ether
3,300
117-81-7
Bis(2-ethylhexyl)phthalate
31,000
75-27-4
Bromodichloromethane (
Dichlorobromomethane)
3,000
75-25-2
Bromoform
1,900
71-36-3
Butanol
10,000
85-68-7
Butyl
benzyl phthalate
930
75-15-0
Carbon disulfide
720
56-23-5
Carbon tetrachloride
1,100
108-90-7
Chlorobenzene (
Monochlorobenzene)
680
124-48-1
Chlorodibromomethane (
Dibromochloromethane)
1,300
67-66-3
Chloroform
2,900
96-12-8
1,2-Dibromo-3-chloropropane
1,400
106-93-4
1,2-Dibromoethane (Ethylene
dibromide)
2,800
84-74-2
Di-
n
-butyl phthalate
2,300
95-50-1
1,2-Dichlorobenzene (o-
Dichlorobenzene)
560
75-34-3
1,1-Dichloroethane
1,700
107-06-2
1,2-Dichloroethane (Ethylene dichloride)
1,800
75-35-4
1,1-Dichloroethylene
1,500
156-59-2
cis
-1,2-Dichloroethylene
1,200
156-60-5
trans
-1,2-Dichloroethylene
3,100
78-87-5
1,2-Dichloropropane
1,100
542-75-6
1,3-Dichloropropene (1,3-Dichloropropylene,
cis
+
trans
)
1,400
131
CAS No.
Chemical Name
C
sat
(mg/kg)
84-66-2
Diethyl phthalate
2,000
117-84-0
Di-
n
-octyl phthalate
10,000
100-41-4
Ethylbenzene
400
77-47-4
Hexachlorocyclopentadiene
2,200
78-59-1
Isophorone
4,600
74-83-9
Methyl bromide (
Bromomethane)
3,200
75-09-2
Methylene chloride (
Dichloromethane)
2,400
98-95-3
Nitrobenzene
1,000
100-42-5
Styrene
1,500
127-18-4
Tetrachloroethylene (Perchloroethylene)
240
108-88-3
Toluene
650
120-82-1
1,2,4-Trichlorobenzene
3,200
71-55-6
1,1,1-Trichloroethane
1,200
79-00-5
1,1,2-Trichloroethane
1,800
79-01-6
Trichloroethylene
1,300
108-05-4
Vinyl acetate
2,700
75-01-4
Vinyl chloride
1,200
108-38-3
m-Xylene
420
95-47-6
o-Xylene
410
106-42-3
p-Xylene
460
1330-20-7
Xylenes (total)
410
Ionizable Organics
95-57-8
2-Chlorophenol
53,000
132
Section 742.APPENDIX A:
General
TABLE B:
Tolerance Factor (K)
Tolerance factors (K) for one-sided normal tolerance intervals with probability level (confidence
factor) Y = 0.95 and coverage P = 95%. n = number of samples collected.
n
K
n
K
3
7.655
4
5.145
5
4.202
6
3.707
7
3.399
8
3.188
9
3.031
10
2.911
11
2.815
12
2.736
13
2.670
14
2.614
15
2.566
16
2.523
17
2.486
18
2.543
19
2.423
20
2.396
21
2.371
22
2.350
23
2.329
24
2.309
25
2.292
30
2.220
35
2.166
40
2.126
45
2.092
50
2.065
55
2.036
60
2.017
65
2.000
70
1.986
75
1.972
100
1.924
125
1.891
150
1.868
175
1.850
200
1.836
225
1.824
250
1.814
275
1.806
300
1.799
325
1.792
350
1.787
375
1.782
400
1.777
425
1.773
450
1.769
475
1.766
500
1.763
525
1.760
550
1.757
575
1.754
600
1.752
625
1.750
650
1.748
675
1.746
700
1.744
725
1.742
750
1.740
775
1.739
800
1.737
825
1.736
850
1.734
875
1.733
900
1.732
925
1.731
950
1.729
975
1.728
1000
1.727
Section 742.APPENDIX A:
General
TABLE C:
Coefficients {A
N-I+1
} for W Test of Normality, for N=2(1)50
i/n
2
3
4
5
6
7
8
9
10
1
0.7071
0.7071
0.6872
0.6646
0.6431
0.6233
0.6052
0.5888
0.5739
2
---
.0000
.1677
.2413
.2806
.3031
.3164
.3244
.3291
3
---
---
---
.0000
.0875
.1401
.1743
.1976
.2141
4
---
---
---
---
---
.0000
.0561
.0947
.1224
5
---
---
---
---
---
---
---
.0000
.0399
i/n
11
12
13
14
15
16
17
18
19
20
1
0.5601
0.5475
0.5359
0.5251
0.5150
0.5056
0.4968
0.4886
0.4808
0.4734
2
.3315
.3325
.3325
.3318
.3306
.3290
.3273
.3253
.3232
.3211
3
.2260
.2347
.2412
.2460
.2495
.2521
.2540
.2553
.2561
.2565
4
.1429
.1586
.1707
.1802
.1878
.1939
.1988
.2027
.2059
.2085
5
.0695
.0922
.1099
.1240
.1353
.1447
.1524
.1587
.1641
.1686
6
0.0000
0.0303
0.0539
0.0727
0.0880
0.1005
0.1109
0.1197
0.1271
0.1334
7
---
---
.0000
.0240
.0433
.0593
.0725
.0837
.0932
.1013
8
---
---
---
---
.0000
.0196
.0359
.0496
.0612
.0711
9
---
---
---
---
---
---
.0000
.0163
.0303
.0422
10
---
---
---
---
---
---
---
---
.0000
.0140
i/n
21
22
23
24
25
26
27
28
29
30
1
0.4643
0.4590
0.4542
0.4493
0.4450
0.4407
0.4366
0.4328
0.4291
0.4254
2
.3185
.3156
.3126
.3098
.3069
.3043
.3018
.2992
.2968
.2944
3
.2578
.2571
.2563
.2554
.2543
.2533
.2522
.2510
.2499
.2487
4
.2119
.2131
.2139
.2145
.2148
.2151
.2152
.2151
.2150
.2148
5
.1736
.1764
.1787
.1807
.1822
.1836
.1848
.1857
.1864
.1870
6
0.1399
0.1443
0.1480
0.1512
0.1539
0.1563
0.1584
0.1601
0.1616
0.1630
7
.1092
.1150
.1201
.1245
.1283
.1316
.1346
.1372
.1395
.1415
8
.0804
.0878
.0941
.0997
.1046
.1089
.1128
.1162
.1192
.1219
9
.0530
.0618
.0696
.0764
.0823
.0876
.0923
.0965
.1002
.1036
10
.0263
.0368
.0459
.0539
.0610
.0672
.0728
.0778
.0822
.0862
11
0.0000
0.0122
0.0228
0.0321
0.0403
0.0476
0.0540
0.0598
0.0650
0.0697
12
---
---
.0000
.0107
.0200
.0284
.0358
.0424
.0483
.0537
13
---
---
---
---
.0000
.0094
.0178
.0253
.0320
.0381
14
---
---
---
---
---
---
.0000
.0084
.0159
.0227
15
---
---
---
---
---
---
---
---
.0000
.0076
i/n
31
32
33
34
35
36
37
38
39
40
1
0.4220
0.4188
0.4156
0.4127
0.4096
0.4068
0.4040
0.4015
0.3989
0.3964
2
.2921
.2898
.2876
.2854
.2834
.2813
.2794
.2774
.2755
.2737
3
.2475
.2463
.2451
.2439
.2427
.2415
.2403
.2391
.2380
.2368
4
.2145
.2141
.2137
.2132
.2127
.2121
.2116
.2110
.2104
.2098
5
.1874
.1878
.1880
.1882
.1883
.1883
.1883
.1881
.1880
.1878
i/n
31
32
33
34
35
36
37
38
39
40
6
0.1641
0.1651
0.1660
0.1667
0.1673
0.1678
0.1683
0.1686
0.1689
0.1691
7
.1433
.1449
.1463
.1475
.1487
.1496
.1503
.1513
.1520
.1526
8
.1243
.1265
.1284
.1301
.1317
.1331
.1344
.1356
.1366
.1376
9
.1066
.1093
.1118
.1140
.1160
.1179
.1196
.1211
.1225
.1237
10
.0899
.0931
.0961
.0988
.1013
.1036
.1056
.1075
.1092
.1108
11
0.0739
0.0777
0.0812
0.0844
0.0873
0.0900
0.0924
0.0947
0.0967
0.0986
12
.0585
.0629
.0669
.0706
.0739
.0770
.0798
.0824
.0848
.0870
13
.0435
.0485
.0530
.0572
.0610
.0645
.0677
.0706
.0733
.0759
14
.0289
.0344
.0395
.0441
.0484
.0523
.0559
.0592
.0622
.0651
15
.0144
.0206
.0262
.0314
.0361
.0404
.0444
.0481
.0515
.0546
16
0.0000
0.0068
0.0131
0.0187
0.0239
0.0287
0.0331
0.0372
0.0409
0.0444
17
---
---
.0000
.0062
.0119
.0172
.0220
.0264
.0305
.0343
18
---
---
---
---
.0000
.0057
.0110
.0158
.0203
.0244
19
---
---
---
---
---
---
.0000
.0053
.0101
.0146
20
---
---
---
---
---
---
---
---
.0000
.0049
i/n
41
42
43
44
45
46
47
48
49
50
1
0.3940
0.3917
0.3894
0.3872
0.3850
0.3830
0.3808
0.3789
0.3770
0.3751
2
.2719
.2701
.2684
.2667
.2651
.2635
.2620
.2604
.2589
.2574
3
.2357
.2345
.2334
.2323
.2313
.2302
.2291
.2281
.2271
.2260
4
.2091
.2085
.2078
.2072
.2065
.2058
.2052
.2045
.2038
.2032
5
.1876
.1874
.1871
.1868
.1865
.1862
.1859
.1855
.1851
.1847
i/n
41
42
43
44
45
46
47
48
49
50
6
0.1693
0.1694
0.1695
0.1695
0.1695
0.1695
0.1695
0.1693
0.1692
0.1691
7
.1531
.1535
.1539
.1542
.1545
.1548
.1550
.1551
.1553
.1554
8
.1384
.1392
.1398
.1405
.1410
.1415
.1420
.1423`
.1427
.1430
9
.1249
.1259
.1269
.1278
.1286
.1293
.1300
.1306
.1312
.1317
10
.1123
.1136
.1149
.1160
.1170
.1180
.1189
.1197
.1205
.1212
11
0.1004
0.1020
0.1035
0.1049
0.1062
0.1073
0.1085
0.1095
0.1105
0.1113
12
.0891
.0909
.0927
.0943
.0959
.0972
.0986
.0998
.1010
.1020
13
.0782
.0804
.0824
.0842
.0860
.0876
.0892
.0906
.0919
.0932
14
.0677
.0701
.0724
.0745
.0775
.0785
.0801
.0817
.0832
.0846
15
.0575
.0602
.0628
.0651
.0673
.0694
.0713
.0731
.0748
.0764
16
0.0476
0.0506
0.0534
0.0560
0.0584
0.0607
0.0628
0.0648
0.0667
0.0685
17
.0379
.0411
.0442
.0471
.0497
.0522
.0546
.0568
.0588
.0608
18
.0283
.0318
.0352
.0383
.0412
.0439
.0465
.0489
.0511
.0532
19
.0188
.0227
.0263
.0296
.0328
.0357
.0385
.0411
.0436
.0459
20
.0094
.0136
.0175
.0211
.0245
.0277
.0307
.0335
.0361
.0386
21
0.0000
0.0045
0.0087
0.0126
0.0163
0.0197
0.0229
0.0259
0.0288
0.0314
22
---
---
.0000
.0042
.0081
.0118
.0153
.0185
.0215
.0244
23
---
---
---
---
.0000
.0039
.0076
.0111
.0143
.0174
24
---
---
---
---
---
---
.0000
.0037
.0071
.0104
25
---
---
---
---
---
---
---
---
.0000
.0035
Section 742.APPENDIX A:
General
TABLE D:
Percentage Points of the W Test for N=3(1)50
n
0.01
0.05
3
0.753
0.767
4
0.687
0.748
5
0.686
0.762
6
0.713
0.788
7
0.730
0.803
8
0.749
0.818
9
0.764
0.829
10
0.781
0.842
11
0.792
0.850
12
0.805
0.859
13
0.814
0.866
14
0.825
0.874
15
0.835
0.881
16
0.844
0.887
17
0.851
0.892
18
0.858
0.897
19
0.863
0.901
20
0.868
0.905
21
0.873
0.908
22
0.878
0.911
23
0.881
0.914
24
0.884
0.916
25
0.888
0.918
26
0.891
0.920
27
0.894
0.923
28
0.896
0.924
29
0.898
0.926
30
0.900
0.927
31
0.902
0.929
32
0.904
0.930
33
0.906
0.931
34
0.908
0.933
35
0.910
0.934
Section 742.APPENDIX A:
General
TABLE E:
Chemicals with Noncarcinogenic Toxic Effects on Specific Target Organs/Organ
Systems or Similar Modes of Action
Kidney
Acetone
Cadmium (Ingestion only)
Chlorobenzene
Dalapon
1,1-Dichloroethane
Di-n-octyl phthalate
Endosulfan
Ethylbenzene
Fluoranthene
Nitrobenzene
Pyrene
Toluene
2,4,5-Trichlorophenol
Vinyl acetate
Liver
Acenaphthene
Acetone
Butylbenzyl phthalate
1,1-Dichloroethylene
Chlorobenzene
Di-n-octyl phthalate
Endrin
Ethylbenzene
Fluoranthene
Nitrobenzene
Picloram
Styrene
2,4,5-TP (
Silvex)
Toluene
2,4,5-Trichlorophenol
Central Nervous System
Butanol
Cyanide
(amendable)
(amenable)
2,4-Dimethylphenol
Endrin
Manganese
2-Methylphenol
Mercury
Styrzene
Xylenes
Circulatory System
Antimony
Barium
2,4-D
cis-1,2-Dichloroethylene
Nitrobenzene
trans 1,2-Dichloroethylene
2,4-Dimethylphenol
Fluoranthene
Fluorene
Styrene
Zinc
Gastrointestinal System
Endothall
Hexachlorocyclopentadiene
Methyl bromide
Reproductive System
Barium
Boron
Carbon disulfide
2-Chlorophenol
1,2 Dibromo-3-Chloropropane (Inhalation only)
Dinoseb
Methoxychlor
Phenol
Cholinesterase Inhibition
Aldicarb
Carbofuran
Decreased Body Weight Gains
and Circulatory System Effects
Atrazine
Simazine
Adrenal Gland
Nitrobenzene
1,2,4-Trichlorobenzene
Respiratory System
1,2-Dichloropropane
Hexachlorocyclopentadiene
Methyl bromide
Vinyl acetate
Immune System
2,4-Dichlorophenol
p-Chloroaniline
Section 742.APPENDIX A: General
TABLE F:
Chemicals With Carcinogenic Toxic Effects on Specific Target Organs/Organ Systems
or Similar Modes of Action
Kidney
Bromodichloromethane
Chloroform
1,2-Dibromo-3-chloropropane
2,4-Dinitrotoluene
2,6-Dinitrotoluene
Hexachlorobenzene
Liver
Aldrin
Bix(2-chloroethyl)ether
Bis(2-ethylhexyl)phthalate
Carbazole
Carbon tetrachloride
Chlordane
Chloroform
DDD
DDE
DDT
1,2-Dibromo-3-chloropropane
1,2-Dibromoethane
3,3
0
-Dichlorobenzidine
1,2-Dichloroethane
1,3-Dichloropropane (Ingestion only)
1,3-Dichloropropylene
Dieldrin
2,4-Dinitrotoluene
2,6-Dinitortoluene
Heptachlor
Heptachlor
epoxide
Hexachlorobenzene
alpha-HCH
gamma-HCH (Lindane)
Methylene chloride
N-Nitrosodiphenylamine
N-Nitrosodi-n-propylamine
Pentachlorophenol
Tetrachloroethylene
Trichloroethylene
2,4,6-Trichlorophenol
Toxaphene
Vinyl chloride
Circulatory System
Benzene
2,4,6-Trichlorophenol
Gastrointestinal System
Benzo(a)anthracene
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Benzo(a)pyrene
Chrysene
Dibenzo(a,h)
anthracene
Indeno(1,2,3-c,d)
pyrene
Bromodichloromethane
Bromoform
1,2-Dibromo-3-chloropropane
1,2-Dibromoethane
1,3-Dichloropropylene
Lung
Arsenic
Beryllium (Inhalation only)
Cadmium (Inhalation only)
Chromium,
hexavalent (Inhalation only)
1,3-Dichloropropylene
Methylene
chroride
N-Nitrosodi-n-propylamine
Vinyl chloride
Nasal Cavity
1,2-Dibromo-3-chloropropane
(Inhalation only)
1,2-Dibromoethane (Inhalation only)
N-Nitrosodi-n-propylamine
Bladder
3,3
0
-Dichlorobenzidine
1,3-Dichloropropylene
N-Nitrosodiphenylamine
Section 742.APPENDIX A:
General
TABLE G:
Concentrations of Inorganic Chemicals in Background Soils
Chemical Name
Counties Within
Metropolitan
Statistical Areas
a
(mg/kg)
Counties Outside
Metropolitan
Statistical Areas
(mg/kg)
Aluminum
9,500
9,200
Antimony
4.0
3.3
Arsenic
7.2
5.2
Barium
110`
122
Beryllium
0.59
0.56
Cadmium
0.6
0.50
Calcium
9,300
5,525
Chromium
16.2
13.0
Cobalt
8.9
8.9
Copper
19.6
12.0
Cyanide
0.51
0.50
Iron
15,900
15,000
Lead
36.0
20.9
Magnesium
4,820
2,700
Manganese
636
630
Mercury
0.06
0.05
a
Counties within Metropolitan Statistical Areas: Boone, Champaign, Clinton, Cook, DuPage,
Grundy, Henry, Jersey, Kane, Kankakee, Kendall, Lake, Macon, Madison, McHenry, McLean,
Menard, Monroe, Peoria, Rock Island, Sangamon, St. Clair, Tazewell, Will, Winnebago, and
Woodford.
b
ND=Below the Detection Limit
Chemical Name
Counties Within
Metropolitan
Statistical Areas
a
(mg/kg)
Counties Outside
Metropolitan
Statistical Areas
(mg/kg)
Nickel
18.0
13.0
Potassium
1,268
1,100
Selenium
0.48
0.37
Silver
0.55
0.50
Sodium
130
130.0
Sulfate
85.5
110
Sulfide
3.1
2.9
Thallium
0.32
0.42
Vanadium
25.2
25.0
Zinc
95.0
60.2
Section 742.APPENDIX A:
General
Illustration A:
Developing Soil Remediation Objectives Under the Tiered Approach
Tier 1
Use look-up tables
Tier 2
Develop objectives
for those
contaminants which
did not meet the Tier
1 objectives.
Tier 3
Develop Tier 3
objectives based on
methods other than
those allowed in
Tier 1 or Tier 2.
Remediate to
Tier 1 objectives
(Instutional controls
may be required)
No Further
Remediation
Remediate to
Tier 2 objectives
(Institutional controls
may be required)
No Further
Remediation
Do you meet the
Tier 3
objectives?
No Further Remediation
(Institutional controls may be required)
Are the Tier 1
remediation
objectives met?
No Further Remediation
(Institutional controls may be required)
No
Develop Tier 2
remediation
objectives
(May include the use of
instutional controls and
engineered barriers)
No Further Remediation
(Institutional controls may be required)
Yes
Develop Tier 3
remediation
objectives
(May include the use of
instutional controls and
engineered barriers)
No
No
Are the Tier 2
objectives met?
Yes
Yes
No
Yes
Remediate to the
Tier 3 objectives.
No
Site
Characterization
and Exposure
Route Evaluation
No
Section 742.APPENDIX A:
General
Illustration B:
Developing Groundwater Remediation Objectives Under the Tiered Approach
Tier 1
Use look-up tables
Tier 2
For contaminants
which did not meet
the Tier 1 objectives
Tier 3
For contaminants
that do not meet the
Tier 1 or Tier 2
remediation
objectives
Remediate to
Tier 1 Levels
(Institutional controls
may be required)
No Further
Remediation
Remediate to the
Tier 2 objective
No Further Remediation
(Institutional controls may be required)
Are the Tier 3
remediation objectives
achieved?
No Further
Remediation
Are the Tier 1
remediation
objectives met?
No Further Remediation
(Institutional controls may be required)
Yes
No
Demonstrate and
calculate onsite and
offsite groundwater
impacts
Develop Tier 3
objectives based on
methods other than
those allowed in Tier
1 or Tier 2
No
No
Are the Tier 2
objectives met?
Yes
No
Develop a Tier 2
groundwater
remediation
objective
Yes
No
Yes
No
Remediate to
objectives
Site
Characterization,
Groundwater
Classification and
Exposure Route
Evaluation
Section 742.APPENDIX B:
Tier 1 Tables and Illustrations
TABLE A:
Tier 1 Soil Remediation Objectives
a
for Residential Properties
Exposure Route-Specific Values for Soils
SoilMigration to
ComponentGroundwater Portion of
the Groundwater Ingestion
Exposure Route
Values
CAS No.
Chemical Name
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Class I
(mg/kg)
Class II
(mg/kg)
ADL
(mg/kg)
83-32-9
Acenaphthene
4,700
b
---
c
570
b
2,900
*
67-64-1
Acetone
7,800
b
100,000
d
16
b
16
*
15972-60-8
Alachlor
o
8
e
---
c
0.04
0.2
NA
116-06-3
Aldicarb
o
78
b
---
c
0.013
0.07
NA
309-00-2
Aldrin
0.04
e
3
e
0.5
e
2.5
*
120-12-7
Anthracene
23,000
b
---
c
12,000
b
59,000
*
1912-24-9
Atrazine
o
2700
b
---
c
0.066
0.33
NA
71-43-2
Benzene
22
e
0.8
e
0.03
0.17
*
56-55-3
Benzo(
a
)anthracene
0.9
e
---
c
2
8
*
205-99-2
Benzo(
b
)fluoranthene
0.9
e
---
c
5
25
*
Exposure Route-Specific Values for Soils
SoilMigration to
ComponentGroundwater Portion of
the Groundwater Ingestion
Exposure Route
Values
CAS No.
Chemical Name
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Class I
(mg/kg)
Class II
(mg/kg)
ADL
(mg/kg)
207-08-9
Benzo(
k
)fluroanthene
9
e
---
c
49
250
*
50-32-8
Benzo(
a
)pyrene
0.09
e,f
---
c
8
82
*
111-44-4
Bis(2-chloroethyl)ether
0.6
e
0.2
e,f
0.0004
e,f
0.0004
0.66
117-81-7
Bis(2-ethylhexyl)phthalate
46
e
31,000
d
3,600
31,000
d
*
75-27-4
Bromodichloromethane
(Dichlorobromomethane)
10
e
3,000
d
0.6
0.6
*
75-25-2
Bromoform
81
e
53
e
0.8
0.8
*
71-36-3
Butanol
7,800
b
10,000
d
17
b
17
NA
85-68-7
Butyl benzyl phthalate
16,000
b
930
d
930
d
930
d
*
86-74-8
Carbazole
32
e
---
c
0.6
e
2.8
NA
1563-66-2
Carbofuran
o
390
b
---
c
0.22
1.1
NA
75-15-0
Carbon disulfide
7,800
b
720
d
32
b
160
*
Exposure Route-Specific Values for Soils
SoilMigration to
ComponentGroundwater Portion of
the Groundwater Ingestion
Exposure Route
Values
CAS No.
Chemical Name
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Class I
(mg/kg)
Class II
(mg/kg)
ADL
(mg/kg)
56-23-5
Carbon tetrachloride
5
e
0.3
e
0.07
0.33
*
57-74-9
Chlordane
0.5
e
20
e
10
48
*
106-47-8
4-Chloroaniline
(p
-Chloroaniline)
310
b
---
c
0.7
b
0.7
1.3
108-90-7
Chlorobenzene
(Monochlorobenzene)
1,600
b
130
b
1
6.5
*
124-48-1
Chlorodibromomethane
(Dibromochloromethane)
1,600
b
1,300
d
0.4
0.4
*
67-66-3
Chloroform
100
e
0.3
e
0.6
2.9
*
218-01-9
Chrysene
88
e
---
c
160
800
*
94-75-7
2,4-D
780
b
---
c
1.5
7.7
*
75-99-0
Dalapon
2,300
b
---
c
0.85
8.5
1.2
72-54-8
DDD
3
e
---
c
16
e
80
*
72-55-9
DDE
2
e
---
c
54
e
270
*
Exposure Route-Specific Values for Soils
SoilMigration to
ComponentGroundwater Portion of
the Groundwater Ingestion
Exposure Route
Values
CAS No.
Chemical Name
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Class I
(mg/kg)
Class II
(mg/kg)
ADL
(mg/kg)
50-29-3
DDT
2
e
---
g
32
e
160
*
53-70-3
Dibenzo(
a,h
)anthracene
0.09
e,f
---
c
2
7.6
*
96-12-8
1,2-Dibromo-3-chloropropane
0.46
e
11
b
0.002
0.002
*
106-93-4
1,2-Dibromoethane
(Ethylene dibromide)
0.0075
e
0.17
e
0.0004
0.004
0.005
84-74-2
Di-
n
-butyl phthalate
7,800
b
2,300
d
2,300
d
2,300
d
*
95-50-1
1,2-Dichlorobenzene
(
o
- Dichlorobenzene)
7,000
b
560
d
17
43
*
106-46-7
1,4-Dichlorobenzene
(
p
- Dichlorobenzene)
---
c
---
g
2
11
*
91-94-1
3,3'-Dichlorobenzidine
1
e
---
c
0.007
e,f
0.033
1.3
75-34-3
1,1-Dichloroethane
7,800
b
1,300
b
23
b
110
*
Exposure Route-Specific Values for Soils
SoilMigration to
ComponentGroundwater Portion of
the Groundwater Ingestion
Exposure Route
Values
CAS No.
Chemical Name
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Class I
(mg/kg)
Class II
(mg/kg)
ADL
(mg/kg)
107-06-2
1,2-Dichloroethane
(Ethylene dichloride)
7
e
0.4
e
0.02
0.1
*
75-35-4
1,1-Dichloroethylene
700
b
1,500
d
0.06
0.3
*
156-59-2
cis
-1,2-Dichloroethylene
780
b
1,200
d
0.4
1.1
*
156-60-5
trans
-1,2-Dichloroethylene
1,600
b
3,100
d
0.7
3.4
*
78-87-5
1,2-Dichloropropane
9
e
15
b
0.03
0.15
*
542-75-6
1,3-Dichloropropene
(1,3-Dichloropropylene,
cis
+
trans
)
4
e
0.1
e
0.004
e
0.02
0.005
60-57-1
Dieldrin
n
0.04
e
1
e
0.004
e
0.02
*
84-66-2
Diethyl phthalate
63,000
b
2,000
d
470
b
470
*
105-67-9
2,4-Dimethylphenol
1,600
b
---
c
9
b
9
*
121-14-2
2,4-Dinitrotoluene
0.9
e
---
c
0.0008
e,f
0.0008
0.013
Exposure Route-Specific Values for Soils
SoilMigration to
ComponentGroundwater Portion of
the Groundwater Ingestion
Exposure Route
Values
CAS No.
Chemical Name
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Class I
(mg/kg)
Class II
(mg/kg)
ADL
(mg/kg)
606-20-2
2,6-Dinitrotoluene
0.9
e
---
c
0.0007
e,f
0.0007
0.0067
117-84-0
Di-
n
-octyl phthalate
1,600
b
10,000
d
10,000
d
10,000
d
*
115-29-7
Endosulfan
470
b
---
c
18
b
90
*
145-73-3
Endothall
o
1,600
b
---
c
0.4
0.4
NA
72-20-8
Endrin
23
b
---
c
1
5
*
100-41-4
Ethylbenzene
7,800
b
400
d
13
19
*
206-44-0
Fluoranthene
3,100
b
---
c
4,300
b
21,000
*
86-73-7
Fluorene
3,100
b
---
c
560
b
2,800
*
76-44-8
Heptachlor
0.1
e
0.1
e
23
110
*
1024-57-3
Heptachlor epoxide
0.07
e
5
e
0.7
3.3
*
118-74-1
Hexachlorobenzene
0.4
e
1
e
2
11
*
319-84-6
alpha
-HCH (
alpha
-BHC)
0.1
e
0.8
e
0.0005
e,f
0.003
0.002
Exposure Route-Specific Values for Soils
SoilMigration to
ComponentGroundwater Portion of
the Groundwater Ingestion
Exposure Route
Values
CAS No.
Chemical Name
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Class I
(mg/kg)
Class II
(mg/kg)
ADL
(mg/kg)
58-89-9
gamma
-HCH (Lindane)
n
0.5
e
---
c
0.009
0.047
*
77-47-4
Hexachlorocyclopentadiene
550
b
10
b
400
2,200
d
*
67-72-1
Hexachloroethane
78
b
---
c
0.5
b
2.6
*
193-39-5
Indeno(1,2,3-
c,d
)pyrene
0.9
e
---
c
14
69
*
78-59-1
Isophorone
15,600
b
4,600
d
8
b
8
*
72-43-5
Methoxychlor
390
b
---
c
160
780
*
74-83-9
Methyl bromide
(Bromomethane)
110
b
10
b
0.2
b
1.2
*
75-09-2
Methylene chloride
(Dichloromethane)
85
e
13
e
0.02
e
0.2
*
95-48-7
2-Methylphenol
(
o
- Cresol)
3,900
b
---
c
15
b
15
*
91-20-3
Naphthalene
3,100
b
---
c
84
b
420
*
98-95-3
Nitrobenzene
39
b
92
b
0.1
b,f
0.1
0.26
Exposure Route-Specific Values for Soils
SoilMigration to
ComponentGroundwater Portion of
the Groundwater Ingestion
Exposure Route
Values
CAS No.
Chemical Name
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Class I
(mg/kg)
Class II
(mg/kg)
ADL
(mg/kg)
86-30-6
N
-Nitrosodiphenylamine
130
e
---
c
1
e
5.6
*
621-64-7
N
-Nitrosodi-
n
-propylamine
0.09
e,f
---
c
0.00005
e,f
0.00005
0.66
108-95-2
Phenol
47,000
b
---
c
100
b
100
*
1918-02-1
Picloram
o
5,500
b
---
c
2
20
NA
1336-36-3
Polychlorinated biphenyls
(PCBs)
n
1; 10
h
---
c,h
---
h
---
h
*
129-00-0
Pyrene
2,300
b
---
c
4,200
b
21,000
*
122-34-9
Simazine
o
390
b
---
c
0.04
0.37
NA
100-42-5
Styrene
16,000
b
1,500
d
4
18
*
127-18-4
Tetrachloroethylene
(Perchloroethylene)
12
e
11
e
0.06
0.3
*
108-88-3
Toluene
16,000
b
650
d
12
29
*
Exposure Route-Specific Values for Soils
SoilMigration to
ComponentGroundwater Portion of
the Groundwater Ingestion
Exposure Route
Values
CAS No.
Chemical Name
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Class I
(mg/kg)
Class II
(mg/kg)
ADL
(mg/kg)
8001-35-2
Toxaphene
n
0.6
e
89
e
31
150
*
120-82-1
1,2,4-Trichlorobenzene
780
b
3,200
b
5
53
*
71-55-6
1,1,1-Trichloroethane
---
c
1,200
d
2
9.6
*
79-00-5
1,1,2-Trichloroethane
310
b
1,800
d
0.02
0.3
*
79-01-6
Trichloroethylene
58
e
5
e
0.06
0.3
*
108-05-4
Vinyl acetate
78,000
b
1,000
b
170
b
170
*
75-01-4
Vinyl chloride
0.3
e
0.03
e
0.01
f
0.07
*
108-38-3
m-Xylene
160,000
b
420
d
210
210
*
95-47-6
o-Xylene
160,000
b
410
d
190
190
*
106-42-3
p-Xylene
160,000
b
460
d
200
200
*
Exposure Route-Specific Values for Soils
SoilMigration to
ComponentGroundwater Portion of
the Groundwater Ingestion
Exposure Route
Values
CAS No.
Chemical Name
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Class I
(mg/kg)
Class II
(mg/kg)
ADL
(mg/kg)
1330-20-7
Xylenes (total)
160,000
b
410
d
150
150
*
Ionizable Organics
65-85-0
Benzoic Acid
310,000
b
---
c
400
b,i
400
i
*
95-57-8
2-Chlorophenol
390
b
53,000
d
4
b,i
420
i
*
120-83-2
2,4-Dichlorophenol
230
b
---
c
1
b,i
1
i
*
51-28-5
2,4-Dinitrophenol
160
b
---
c
0.2
b,f
0.2
3.3
88-85-7
Dinoseb
o
78
b
---
c
0.34
b,i
3.4
i
*
87-86-5
Pentachlorophenol
3
e,j
---
c
0.03
f,i
0.14
i
2.4
93-72-1
2,4,5-TP
(Silvex)
630
b
---
c
11
i
55
i
*
95-95-4
2,4,5-Trichlorophenol
7,800
b
---
c
270
b,i
1,400
i
*
88-06-2
2,4,6 Trichlorophenol
58
e
200
e
0.2
e,f,i
0.77
i
0.43
Exposure Route-specific Values for Soils
SoilMigration to
ComponentGroundwater Portion of
the Groundwater Ingestion
Exposure Route
Values
CAS No.
Chemical Name
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Class I
(mg/L)
TCLP
Class II
(mg/L)
TCLP
ADL
(mg/kg)
Inorganics
7440-36-0
Antimony
31
b
---
c
0.006
m
0.024
m
*
7440-38-2
Arsenic
l,n
0.4
e,t
750
e
0.05
m
0.2
m
*
7440-39-3
Barium
5,500
b
690,000
b
2.0
m
2.0
m
*
7440-41-7
Beryllium
0.1
e,t
1,300
e
0.004
m
0.5
m
*
7440-42-8
Boron
7,000
b
---
g
2.0
m
2.0
m
*
7440-43-9
Cadmium
l,n
78
b, r
1,800
e
0.005
m
0.05
m
*
16887-00-6
Chloride
---
c
---
c
200
m
200
m
*
7440-47-3
Chromium, total
390
b
270
e
0.1
m
1.0
m
*
16065-83-1
Chromium, ion, trivalent
78,000
b
---
c
---
g
---
g
*
18540-29-9
Chromium, ion, hexavalent
390
b
270
e
---
---
*
7440-48-4
Cobalt
4,700
b
---
c
1.0
m
1.0
m
*
Exposure Route-specific Values for Soils
SoilMigration to
ComponentGroundwater Portion of
the Groundwater Ingestion
Exposure Route
Values
CAS No.
Chemical Name
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Class I
(mg/L)
TCLP
Class II
(mg/L)
TCLP
ADL
(mg/kg)
7440-50-8
Copper
n
2,900
b
---
c
0.65
m
0.65
m
*
57-12-5
Cyanide (amenable)
1,600
b
---
c
0.2
q
0.6
q
*
7782-41-4
Fluoride
4,700
b
---
c
4.0
m
4.0
m
*
15438-31-0
Iron
---
c
---
c
5.0
m
5.0
m
*
7439-92-1
Lead
400
k
---
c
0.0075
m
0.1
m
*
7439-96-5
Manganese
3,700
b
69,000
b
0.15
m
10.0
m
*
7439-97-6
Mercury
l,n
23
b,s
10
b,i
0.002
m
0.01
m
*
7440-02-0
Nickel
l
1,600
b
13,000
e
0.1
m
2.0
m
*
14797-55-8
Nitrate as N
p
130,000
b
---
c
10.0
q
100
q
*
7782-49-2
Selenium
l,n
390
b
---
c
0.05
m
0.05
m
*
Exposure Route-specific Values for Soils
SoilMigration to
ComponentGroundwater Portion of
the Groundwater Ingestion
Exposure Route
Values
CAS No.
Chemical Name
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Class I
(mg/L)
TCLP
Class II
(mg/L)
TCLP
ADL
(mg/kg)
7440-22-4
Silver
390
b
---
c
0.05
m
---
*
14808-79-8
Sulfate
---
c
---
c
400
m
400
m
*
7440-28-0
Thallium
6.3
b,u
---
c
0.002
m
0.02
m
*
7440-62-2
Vanadium
550
b
---
c
0.049
m
---
*
7440-66-6
Zinc
l
23,000
b
---
c
5.0
m
10
m
*
"*" indicates that the ADL is less than or equal to the specified cleanup objective.
NA means not available; no PQL or EQL available in USEPA analytical methods.
Chemical Name and Soil RemediationCleanup Objective Notations
a
Soil remediationcleanup objectives based on human health criteria only.
b
Calculated values correspond to a target hazard quotient of 1.
c
No toxicity criteria available for the route of exposure.
d
Soil saturation concentration (C
sat
) = the concentration at which the absorptive limits of the soil particles, the solubility limits of the available soil
moisture, and saturation of soil pore air have been reached. Above the soil saturation concentration, the assumptions regarding vapor transport to air
and/or dissolved phase transport to groundwater (for chemicals which are liquid at ambient soil temperatures) have been violated, and alternative
modeling approaches are required.
e
Calculated values correspond to a cancer risk level of 1 in 1,000,000.
f
Level is at or below Contract Laboratory Program required quantitation limit for Regular Analytical Services (RAS).
g
Chemical-specific properties are such that this route is not of concern at any soil contaminant concentration.
h
A preliminary goal of 1 ppm has been set for PCBs based on
Guidance on Remedial Actions for Superfund Sites with PCB Contamination
, EPA/540G-
90/007, and on USEPA efforts to manage PCB contamination. See 40 CFR 761.120 - USEPA "PCB Spill Cleanup Policy." This regulation goes on to
say that the cleanup goal for an unrestricted area is 10 ppm and 25 ppm for a restricted area, provided both have at least 10 inches of clean cover.
i
Soil remediationcleanup objective for pH of 6.8. If soil pH is other than 6.8, refer to Appendix B, Tables C and D of this Part.
j
Ingestion soil remediationcleanup objective adjusted by a factor of 0.5 to account for dermal route.
k
A preliminary remediation goal of 400 mg/kg has been set for lead based on
Revised Interim Soil Lead Guidance for CERCLA Sites and RCRA Corrective
Action Facilities
, OSWER Directive #9355.4-12.
l
Potential for soil-plant-human exposure.
m
Concentration in mg/L determined by the Toxicity Characteristic Leaching Procedure (TCLP). The person conducting the remediation has the option to
use: 1) TCLP or SPLP test results to compare with the remediation objectives cleanup objectives listed in this Table; or 2) the total amount of
contaminant in the soil sample results to compare with pH specific remediation objectivesthe applicable pH-specific soil cleanup objectiveslisted in
Appendix B, Tables C or D of this Part. (See Section 742.510) If the person conducting the remediation wishes to calculate soil remediationcleanup
objectives based on background concentrations, this should be done in accordance with Subpart D of this Part.
n
The Agency reserves the right to evaluate the potential for remaining contaminant concentrations to pose significant threats to crops, livestock, or
wildlife.
o
For agrichemical facilities, remediationcleanup objectives for surficial soils which are based on field application rates may be more appropriate for
currently registered pesticides. Consult the Agency for further information.
p
For agrichemical facilities, soil remediationcleanup objectives based on site-specific background concentrations of Nitrate as N may be more
appropriate. Such determinations shall be conducted in accordance with the procedures set forth in Subparts D and I of this Part.
q
For Cyanide the TCLP extraction must be done using water at a pH of 7.0.
r
Value based on dietary Reference Dose.
s
Value based on Reference Dose for Mercuric chloride (CAS No. 7487-94-7).
t
Note that Table value is likely to be less than background concentration for this chemical; screening or remediation concentrations using the procedures
of Subpart D of this Part may be more appropriate.
u
Value based on Reference Dose for thallium sulfate (CAS No. 7446-18-6)
Section 742.APPENDIX B:
Tier 1 Tables and Illustrations
Table B:
Tier 1 Soil Remediation Objectives
a
for Industrial/Commercial Properties
Exposure Route-Specific Values for Soils
SoilMigration to
ComponentGroundwa
ter
Portion of the
Groundwater
Ingestion Exposure
Route
Industrial-
Commercial
Construction
Worker
Values
CAS No.
Chemical
Name
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Class I
(mg/kg)
ClassII
(mg/kg)
ADL
(mg/kg)
83-32-9
Acenaphthene
120,000
b
-----
c
120,000
b
-----
c
570
b
2,900
*
67-64-1
Acetone
200,000
b
100,000
d
200,000
b
100,000
d
16
b
16
*
15972-60-8
Alachlor
o
72
e
-----
c
1,600
e
-----
c
0.04
0.2
NA
116-06-3
Aldicarb
o
2,000
b
-----
c
200
b
-----
c
0.013
0.07
NA
309-00-2
Aldrin
0.3
e
6.6
e
6.1
b
9.3
e
0.5
e
2.5
*
120-12-7
Anthracene
610,000
b
-----
c
610,000
b
-----
c
12,000
b
59,000
*
1912-24-9
Atrazine
o
72,000
b
-----
c
7,100
b
-----
c
0.066
0.33
NA
71-43-2
Benzene
200
e
1.5
e
4,300
e
2.1
e
0.03
0.17
*
Exposure Route-Specific Values for Soils
SoilMigration to
ComponentGroundwa
ter
Portion of the
Groundwater
Ingestion Exposure
Route
Industrial-
Commercial
Construction
Worker
Values
CAS No.
Chemical
Name
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Class I
(mg/kg)
Class II
(mg/kg)
ADL
(mg/kg)
56-55-3
Benzo(
a
)anthracene
8
e
-----
c
170
e
-----
c
2
8
*
205-99-2
Benzo(
b
)fluoranthene
8
e
-----
c
170
e
-----
c
5
25
*
207-08-9
Benzo(
k
)fluroanthene
78
e
-----
c
1,700
e
-----
c
49
250
*
50-32-8
Benzo(
a
)pyrene
0.8
e
-----
c
17
e
-----
c
8
82
*
111-44-4
Bis(2-chloroethyl)ether
5
e
0.47
e
75
e
0.66
e
0.0004
e,f
0.0004
0.66
117-81-7
Bis(2-ethylhexyl)phthalate
410
e
31,000
d
4,100
b
31,000
d
3,600
31,000
d
*
75-27-4
Bromodichloromethane
(Dichlorobromomethane)
92
e
3,000
d
2,000
e
3,000
d
0.6
0.6
*
75-25-2
Bromoform
720
e
100
e
16,000
e
140
e
0.8
0.8
*
71-36-3
Butanol
200,000
b
10,000
d
200,000
b
10,000
d
17
b
17
NA
85-68-7
Butyl benzyl phthalate
410,000
b
930
d
410,000
b
930
d
930
d
930
d
*
86-74-8
Carbazole
290
e
-----
c
6,200
e
-----
c
0.6
e
2.8
NA
Exposure Route-Specific Values for Soils
SoilMigration to
ComponentGroundwa
ter
Portion of the
Groundwater
Ingestion Exposure
Route
Industrial-
Commercial
Construction
Worker
Values
CAS No.
Chemical
Name
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Class I
(mg/kg)
Class II
(mg/kg)
ADL
(mg/kg)
1563-66-2
Carbofuran
o
10,000
b
-----
c
1,000
b
-----
c
0.22
1.1
NA
75-15-0
Carbon disulfide
200,000
b
720
d
20,000
b
9.0
b
32
b
160
*
56-23-5
Carbon tetrachloride
44
e
0.64
e
410
b
0.90
e
0.07
0.33
*
57-74-9
Chlordane
4
e
38
e
12
b
53
e
10
48
*
106-47-8
4 - Chloroaniline
(p
-Chloroaniline)
8,200
b
-----
c
820
b
-----
c
0.7
b
0.7
1.3
108-90-7
Chlorobenzene
(Monochlorobenzene)
41,000
b
210
b
4,100
b
1.3
b
1
6.5
*
124-48-1
Chlorodibromomethane
(Dibromochloromethane)
41,000
b
1,300
d
41,000
b
1,300
d
0.4
0.4
*
67-66-3
Chloroform
940
e
0.54
e
2,000
b
0.76
e
0.6
2.9
*
218-01-9
Chrysene
780
e
-----
c
17,000
e
-----
e
160
800
*
94-75-7
2,4-D
20,000
b
-----
c
2,000
b
-----
c
1.5
7.7
*
Exposure Route-Specific Values for Soils
SoilMigration to
ComponentGroundwa
ter
Portion of the
Groundwater
Ingestion Exposure
Route
Industrial-
Commercial
Construction
Worker
Values
CAS No.
Chemical
Name
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Class I
(mg/kg)
Class II
(mg/kg)
ADL
(mg/kg)
75-99-0
Dalapon
61,000
b
-----
c
6,100
b
-----
c
0.85
8.5
1.2
72-54-8
DDD
24
e
-----
c
520
e
-----
c
16
e
80
*
72-55-9
DDE
17
e
-----
c
370
e
-----
c
54
e
270
*
50-29-3
DDT
17
e
1,500
e
100
b
2,100
e
32
e
160
*
53-70-3
Dibenzo(
a,h
)anthracene
0.8
e
-----
c
17
e
-----
c
2
7.6
*
96-12-8
1,2-Dibromo-3-chloropropane
4
e
17
b
89
e
0.11
b
0.002
0.002
*
106-93-4
1,2-Dibromoethane
(Ethylene dibromide)
0.07
e
0.32
e
1.5
e
0.45
e
0.0004
0.004
0.005
84-74-2
Di-
n
-butyl phthalate
200,000
b
2,300
d
200,000
b
2,300
d
2,300
d
2,300
d
*
95-50-1
1,2-Dichlorobenzene
(
o
- Dichlorobenzene)
180,000
b
560
d
18,000
b
310
b
17
43
*
106-46-7
1,4-Dichlorobenzene
(
p
- Dichlorobenzene)
-----
c
17,000
b
-----
c
340
b
2
11
*
Exposure Route-Specific Values for Soils
SoilMigration to
ComponentGroundwa
ter
Portion of the
Groundwater
Ingestion Exposure
Route
Industrial-
Commercial
Construction
Worker
Values
CAS No.
Chemical
Name
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Class I
(mg/kg)
Class II
(mg/kg)
ADL
(mg/kg)
91-94-1
3,3'-Dichlorobenzidine
13
e
-----
c
280
e
-----
c
0.007
e,f
0.033
1.3
75-34-3
1,1-Dichloroethane
200,000
b
1,700
d
200,000
b
130
b
23
b
110
*
107-06-2
1,2-Dichloroethane
(Ethylene dichloride)
63
e
0.70
e
1,400
e
0.99
e
0.02
0.1
*
75-35-4
1,1-Dichloroethylene
18,000
b
1,500
d
1,800
b
1,500
d
0.06
0.3
*
156-59-2
cis
-1,2-Dichloroethylene
20,000
b
1,200
d
20,000
b
1,200
d
0.4
1.1
*
156-60-5
trans
-1,2-Dichloroethylene
41,000
b
3,100
d
41,000
b
3,100
d
0.7
3.4
*
78-87-5
1,2-Dichloropropane
84
e
23
b
1,800
e
0.50
b
0.03
0.15
*
542-75-6
1,3-Dichloropropene
(1,3-Dichloropropylene,
cis
+
trans
)
33
e
0.23
e
610
b
0.33
e
0.004
e
0.02
0.005
60-57-1
Dieldrin
n
0.4
e
2.2
e
7.8
e
3.1
e
0.004
e
0.02
0.0013
84-66-2
Diethyl phthalate
1,000,000
b
2,000
d
1,000,000
b
2,000
d
470
b
470
*
Exposure Route-Specific Values for Soils
SoilMigration to
ComponentGroundwa
ter
Portion of the
Groundwater
Ingestion Exposure
Route
Industrial-
Commercial
Construction
Worker
Values
CAS No.
Chemical
Name
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Class I
(mg/kg)
Class II
(mg/kg)
ADL
(mg/kg)
105-67-9
2,4-Dimethylphenol
41,000
b
-----
c
41,000
b
-----
c
9
b
9
*
121-14-2
2,4-Dinitrotoluene
8.4
e
-----
c
180
e
-----
c
0.0008
e,f
0.0008
0.013
606-20-2
2,6-Dinitrotoluene
8.4
e
-----
c
180
e
-----
c
0.0007
e,f
0.0007
0.0067
117-84-0
Di-
n
-octyl phthalate
41,000
e
10,000
d
4,100
b
10,000
d
10,000
d
10,000
d
*
115-29-7
Endosulfan
12,000
b
-----
c
1,200
b
-----
c
18
b
90
*
145-73-3
Endothall
o
41,000
c
-----
c
4,100
b
-----
c
0.4
0.4
NA
72-20-8
Endrin
610
b
-----
c
61
b
-----
c
1
5
*
100-41-4
Ethylbenzene
200,000
b
400
d
20,000
b
58
b
13
19
*
206-44-0
Fluoranthene
82,000
b
-----
c
82,000
b
-----
c
4,300
b
21,000
*
86-73-7
Fluorene
82,000
b
-----
c
82,000
b
-----
c
560
b
2,800
*
76-44-8
Heptachlor
1
e
11
e
28
e
16
e
23
110
*
Exposure Route-Specific Values for Soils
SoilMigration to
ComponentGroundwa
ter
Portion of the
Groundwater
Ingestion Exposure
Route
Industrial-
Commercial
Construction
Worker
Values
CAS No.
Chemical
Name
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Class I
(mg/kg)
Class II
(mg/kg)
ADL
(mg/kg)
1024-57-3
Heptachlor epoxide
0.6
e
9.2
e
2.7
b
13
e
0.7
3.3
*
118-74-1
Hexachlorobenzene
4
e
1.8
e
78
e
2.6
e
2
11
*
319-84-6
alpha
-HCH (
alpha
-BHC)
0.9
e
1.5
e
20
e
2.1
e
0.0005
e,f
0.003
0.002
58-89-9
gamma
-HCH (Lindane)
n
4
e
-----
c
96
e
-----
c
0.009
0.047
*
77-47-4
Hexachlorocyclopentadiene
14,000
b
16
b
14,000
b
1.1
b
400
2,200
d
*
67-72-1
Hexachloroethane
2,000
b
-----
c
2,000
b
-----
c
0.5
b
2.6
*
193-39-5
Indeno(1,2,3-
c,d
)pyrene
8
e
-----
c
170
e
-----
c
14
69
*
78-59-1
Isophorone
410,000
b
4,600
d
410,000
b
4,600
d
8
b
8
*
72-43-5
Methoxychlor
10,000
b
-----
c
1,000
b
-----
c
160
780
*
74-83-9
Methyl bromide
(Bromomethane)
2,900
b
15
b
1,000
b
3.9
b
0.2
b
1.2
*
Exposure Route-Specific Values for Soils
SoilMigration to
ComponentGroundwa
ter
Portion of the
Groundwater
Ingestion Exposure
Route
Industrial-
Commercial
Construction
Worker
Values
CAS No.
Chemical
Name
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Class I
(mg/kg)
Class II
(mg/kg)
ADL
(mg/kg)
75-09-2
Methylene chloride
(Dichloromethane)
760
e
24
e
12,000
b
34
e
0.02
e
0.2
*
95-48-7
2-Methylphenol
(
o
- Cresol)
100,000
b
-----
c
100,000
b
-----
c
15
b
15
*
86-30-6
N
-Nitrosodiphenylamine
1,200
e
-----
c
25,000
e
-----
c
1
e
5.6
0.66
621-64-7
N
-Nitrosodi-
n
-propylamine
0.8
e
-----
c
18
e
-----
c
0.00005
e,f
0.00005
0.66
91-20-3
Naphthalene
82,000
b
-----
c
8,200
b
-----
c
84
b
420
*
98-95-3
Nitrobenzene
1,000
b
140
b
1,000
b
9.4
b
0.1
b,f
0.1
0.26
108-95-2
Phenol
1,000,000
b
-----
c
120,000
b
-----
c
100
b
100
*
1918-02-1
Picloram
o
140,000
b
-----
c
14,000
b
-----
c
2
20
NA
1336-36-3
Polychlorinated biphenyls (PCBs)
n
1; 10; 25
h
-----
c,h
1
h
-----
c,h
-----
h
-----
h
*
129-00-0
Pyrene
61,000
b
-----
c
61,000
b
-----
c
4,200
b
21,000
*
Exposure Route-Specific Values for Soils
SoilMigration to
ComponentGroundwa
ter
Portion of the
Groundwater
Ingestion Exposure
Route
Industrial-
Commercial
Construction
Worker
Values
CAS No.
Chemical
Name
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Class I
(mg/kg)
Class II
(mg/kg)
ADL
(mg/kg)
122-34-9
Simazine
o
10,000
b
-----
c
1,000
b
-----
c
0.04
0.37
NA
100-42-5
Styrene
410,000
b
1,500
d
41,000
b
430
b
4
18
*
127-18-4
Tetrachloroethylene
(Perchloroethylene)
110
e
20
e
2,400
e
28
e
0.06
0.3
*
108-88-3
Toluene
410,000
b
650
d
410,000
b
42
b
12
29
*
8001-35-2
Toxaphene
n
5.2
e
170
e
110
e
240
e
31
150
*
120-82-1
1,2,4-Trichlorobenzene
20,000
b
3,200
d
2,000
b
920
b
5
53
*
71-55-6
1,1,1-Trichloroethane
-----
c
1,200
d
-----
c
1,200
d
2
9.6
*
79-00-5
1,1,2-Trichloroethane
8,200
b
1,800
d
8,200
b
1,800
d
0.02
0.3
*
79-01-6
Trichloroethylene
520
e
8.9
e
1,200
b
12
e
0.06
0.3
*
108-05-4
Vinyl acetate
1,000,000
b
1,600
b
200,000
b
10
b
170
b
170
*
Exposure Route-Specific Values for Soils
SoilMigration to
ComponentGroundwa
ter
Portion of the
Groundwater
Ingestion Exposure
Route
Industrial-
Commercial
Construction
Worker
Values
CAS No.
Chemical
Name
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Class I
(mg/kg)
Class II
(mg/kg)
ADL
(mg/kg)
75-01-4
Vinyl chloride
3
e
0.06
e
65
e
0.08
e
0.01
f
0.07
*
108-38-3
m-Xylene
1,000,000
420
d
410,000
b
420
d
210
210
*
95-47-6
o-Xylene
1,000,000
410
d
410,000
b
410
d
190
190
*
106-42-3
p-Xylene
1,000,000
460
d
410,000
b
460
d
200
200
*
1330-20-7
Xylenes (total)
1,000,000
b
410
d
410,000
b
410
d
150
150
*
Ionizable Organics
65-85-0
Benzoic Acid
1,000,000
b
-----
c
820,000
b
-----
c
400
b,i
400
i
*
95-57-8
2-Chlorophenol
10,000
b
53,000
d
10,000
b
53,000
d
4
b,i
20
i
*
120-83-2
2,4-Dichlorophenol
6,100
b
-----
c
610
b
-----
c
1
b,i
1
i
*
51-28-5
2,4-Dinitrophenol
4,100
b
-----
c
410
b
-----
c
0.2
b,f,i
0.2
i
3.3
88-85-7
Dinoseb
o
2,000
b
-----
c
200
b
-----
c
0.34
b,i
3.4
i
*
Exposure Route-Specific Values for Soils
SoilMigration to
ComponentGroundwa
ter
Portion of the
Groundwater
Ingestion Exposure
Route
Industrial-
Commercial
Construction
Worker
Values
CAS No.
Chemical
Name
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Class I
(mg/kg)
Class II
(mg/kg)
ADL
(mg/kg)
87-86-5
Pentachlorophenol
24
e,j
-----
c
520
e,j
-----
c
0.03
f,i
0.14
i
2.4
93-72-1
2,4,5-TP
(Silvex)
16,000
b
-----
c
1,600
b
-----
c
11
i
55
i
*
95-95-4
2,4,5-Trichlorophenol
200,000
b
-----
c
200,000
b
-----
c
270
b,i
1,400
i
*
88-06-2
2,4,6- Trichlorophenol
520
e
390
e
11,000
e
540
e
0.2
e,f,i
0.77
i
0.43
Exposure Route-Specific Values for Soils
SoilMigration to
ComponentGroundwat
er
Portion of the
Groundwater
Ingestion Exposure
Route
Industrial-
Commercial
Construction
Worker
Values
CAS No.
Chemical
Name
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Class I
(mg/L)
Class II
(mg/L)
Inorganics
7440-36-0
Antimony
820
b
-----
c
82
b
-----
c
0.006
m
0.024
m
*
7440-38-2
Arsenic
l,n
3
e,t
1,200
e
61
b
25,000
e
0.05
m
0.2
m
7440-39-3
Barium
140,000
b
910,000
b
14,000
b
870,000
b
2.0
m
2.0
m
*
7440-41-7
Beryllium
1
e,t
2,100
e
29
e
44,000
e
0.004
m
0.5
m
*
7440-42-8
Boron
180,000
b
1,000,000
18,000
b
1,000,000
2.0
m
2.0
m
*
7440-43-9
Cadmium
l,n
2,000
b,r
2,800
e
200
b,r
59,000
e
0.005
m
0.05
m
*
16887-00-6
Chloride
-------
c
-----
c
-----
c
-----
c
200
m
200
m
*
7440-47-3
Chromium, total
10,000
b
420
e
4,100
b
8,800
e
0.1
m
1.0
m
*
16065-83-1
Chromium, ion, trivalent
1,000,000
b
-----
c
330,000
b
-----
c
-----
g
-----
g
*
18540-29-9
Chromium, ion, hexavalent
10,000
b
420
e
4,100
b
8,800
e
-----
-----
*
Exposure Route-Specific Values for Soils
SoilMigration to
ComponentGroundwat
er
Portion of the
Groundwater
Ingestion Exposure
Route
Industrial-
Commercial
Construction
Worker
Values
CAS No.
Chemical
Name
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Class I
(mg/L)
Class II
(mg/L)
7440-48-4
Cobalt
120,000
b
-----
c
12,000
b
-----
c
1.0
m
1.0
m
*
7440-50-8
Copper
n
82,000
b
-----
c
8,200
b
-----
c
0.65
m
0.65
m
*
57-12-5
Cyanide (amenable)
41,000
b
-----
c
4,100
b
-----
c
0.2
q
0.6
q
*
7782-41-4
Fluoride
120,000
b
-----
c
12,000
b
-----
c
4.0
m
4.0
m
*
15438-31-0
Iron
-----
c
-----
c
-----
c
-----
c
5.0
m
5.0
m
*
7439-92-1
Lead
400
k
-----
c
400
k
-----
c
0.0075
m
0.1
m
*
7439-96-5
Manganese
96,000
b
91,000
b
9,600
b
8,700
b
0.15
m
10.0
m
*
7439-97-6
Mercury
l,n
610
b
540,000
b
61
b,s
52,000
b
0.002
m
0.01
m
*
7440-02-0
Nickel
l
41,000
b
21,000
e
4,100
b
440,000
e
0.1
m
2.0
m
*
14797-55-8
Nitrate as N
p
1,000,000
b
-----
c
330,000
b
-----
c
10.0
q
100
q
*
7782-49-2
Selenium
l,n
10,000
b
-----
c
1,000
b
-----
c
0.05
m
0.05
m
*
Exposure Route-Specific Values for Soils
SoilMigration to
ComponentGroundwat
er
Portion of the
Groundwater
Ingestion Exposure
Route
Industrial-
Commercial
Construction
Worker
Values
CAS No.
Chemical
Name
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Ingestion
(mg/kg)
Inhalation
(mg/kg)
Class I
(mg/L)
Class II
(mg/L)
7440-22-4
Silver
10,000
b
-----
c
1,000
b
-----
c
0.05
m
-----
*
14808-79-8
Sulfate
-----
c
-----
c
-----
c
-----
c
400
m
400
m
*
7440-28-0
Thallium
160
b,u
-----
c
160
b,u
-----
c
0.002
m
0.02
m
*
7440-62-2
Vanadium
14,000
b
-----
c
1,400
b
-----
c
0.049
m
-----
*
7440-66-6
Zinc
l
610,000
b
-----
c
61,000
b
-----
c
5.0
m
10
m
*
"*" indicates that the ADL is less than or equal to the specified cleanup objective.
NA means Not Available; no PQL or EQL available in USEPA analytical methods.
Chemical Name and Soil RemediationCleanup Objective Notations (2nd, 5th thru 8th Columns)
a
Soil remediationcleanup objectives based on human health criteria only.
b
Calculated values correspond to a target hazard quotient of 1.
c
No toxicity criteria available for this route of exposure.
d
Soil saturation concentration (C
sat
) = the concentration at which the absorptive limits of the soil particles, the solubility limits of the available soil moisture, and
saturation of soil pore air have been reached. Above the soil saturation concentration, the assumptions regarding vapor transport to air and/or dissolved phase
transport to groundwater (for chemicals which are liquid at ambient soil temperatures) have been violated, and alternative modeling approaches are required.
e
Calculated values correspond to a cancer risk level of 1 in 1,000,000. Site-specific conditions may warrant use of a greater risk level but not to exceed 1 in 10,000.
f
Level is at or below Contract Laboratory Program required quantitation limit for Regular Analytical Services (RAS).
g
Chemical-specific properties are such that this route is not of concern at any soil contaminant concentration.
h
A preliminary goal of 1 ppm has been set for PCBs based on
Guidance on Remedial Actions for Superfund Sites with PCB Contamination
, EPA/540G-90/007, and on
USEPA efforts to manage PCB contamination. See 40 CFR 761.120 for USEPA "PCB Spill Cleanup Policy." This regulation goes on to say that the cleanup goal for
an unrestricted area is 10 ppm and 25 ppm for a restricted area, provided both have at least 10 inches of clean cover.
Ii
Soil remediationcleanup objective for pH of 6.8. If soil pH is other than 6.8, refer to Appendix B, Tables C and D in this Part.
j
Ingestion soil remediationcleanup objective adjusted by a factor of 0.5 to account for dermal route.
k
A preliminary remediation goal of 400 mg/kg has been set for lead based on
Revised Interim Soil Lead Guidance for CERCLA Sites and RCRA Corrective Action
Facilities
, OSWER Directive #9355.4-12.
l
Potential for soil-plant-human exposure.
m
Concentration in mg/L determined by the Toxicity Characteristic Leaching Procedure (TCLP). The person conducting the remediation has the option to use: 1) TCLP
or SPLP test results to compare with the remediation objectives cleanup objectives listed in this Table; or 2) the total amount of contaminant in the soil sample results
to compare with pH specific remediation objectives of the applicable pH-specific soil cleanup objectives listed in Appendix B, Tables C or D of this Part. (See
Section 742.510). If the person conducting the remediation wishes to calculate soil remediation cleanup objectives based on background concentrations, this should be
done in accordance with Subpart D of this Part.
n
The Agency reserves the right to evaluate the potential for remaining contaminant concentrations to pose significant threats to crops, livestock, or wildlife.
o
For agrichemical facilities, cleanup remediation objectives for surficial soils which are based on field application rates may be more appropriate for currently
registered pesticides. Consult the Agency for further information.
p
For agrichemical facilities, soil remediation cleanup objectives based on site-specific background concentrations of Nitrate as N may be more appropriate. Such
determinations shall be conducted in accordance with the located in Subparts D and I of this Part.
q
For Cyanide the TCLP extraction must be done using water at a pH of 7.0.
r
Value based on dietary Reference Dose.
s
Value based on Reference Dose for Mercuric chloride (CAS No. 7487-94-7).
t
Note that Table value is likely to be less than background concentration for this chemical; screening or remediation concentrations using the procedures of Subpart D
of this Part.
u
Value based on Reference Dose for thallium sulfate (CAS No. 7446-18-6)
Section 742.APPENDIX B:
Tier 1 Tables and Illustrations
Table C:
pH Specific Soil Remediation Objectives for Inorganics and Ionizing Organics for the SoilMigration to
ComponentGroundwater Portion of the Groundwater Ingestion Route (Class I Groundwater)
Chemical (totals)
(mg/kg)
pH 4.5 to
4.74
pH 4.75
to 5.24
pH 5.25
to 5.74
pH 5.75
to 6.24
pH 6.25
to 6.64
pH 6.65
to 6.89
pH 6.9
to 7.24
pH 7.25
to 7.74
pH 7.75
to 8.0
Inorganics
Antimony
5
5
5
5
5
5
5
5
5
Arsenic
25
26
27
28
29
29
29
30
31
Barium
260
490
850
1,200
1,500
1,600
1,700
1,800
2,100
Beryllium
1.1
2.1
3.4
6.6
22
63
140
1,000
8,000
Cadmium
1.0
1.7
2.7
3.7
5.2
7.5
11
59
430
Chromium (+6)
70
62
54
46
40
38
36
32
28
Copper
330
580
2,100
11,000
59,000
130,000
200,000
330,000
330,000
Cyanide
40
40
40
40
40
40
40
40
40
Mercury
0.01
0.01`
0.03
0.15
0.89
2.1
3.3
6.4
8.0
Nickel
20
36
56
76
100
130
180
700
3,800
Selenium
24
17
12
8.8
6.3
5.2
4.5
3.3
2.4
Silver
0.24
0.33
0.62
1.5
4.4
8.5
13
39
110
Chemical (totals)
(mg/kg)
pH 4.5 to
4.74
pH 4.75
to 5.24
pH 5.25
to 5.74
pH 5.75
to 6.24
pH 6.25
to 6.64
pH 6.65
to 6.89
pH 6.9
to 7.24
pH 7.25
to 7.74
pH 7.75
to 8.0
Thallium
1.6
1.8
2.0
2.4
2.6
2.8
3.0
3.4
3.8
Vanadium
980
980
980
980
980
980
980
980
980
Zinc
1,000
1,800
2,600
3,600
5,100
6,200
7,500
16,000
53,000
Organics
Benzoic Acid
440
420
410
400
400
400
400
400
400
2-Chlorophenol
4.0
4.0
4.0
4.0
3.9
3.9
3.9
3.6
3.1
2,4-Dichlorophenol
1.0
1.0
1.0
1.0
1.0
1.0
1.0
0.86
0.69
Dinoseb
8.4
4.5
1.9
0.82
0.43
0.34
0.31
0.27
0.25
Pentachlorophenol
0.54
0.32
0.15
0.07
0.04
0.03
0.02
0.02
0.02
2,4,5-TP (Silvex)
26
16
12
11
11
11
11
11
11
2,4,5-Trichlorophenol
400
390
390
370
320
270
230
130
64
2,4,6-Trichlorophenol
0.37
0.36
0.34
0.26
0.20
0.15
0.13
0.09
0.07
Section 742.APPENDIX B
Table D:
pH Specific Soil Remediation Objectives for Inorganics and Ionizing Organics for the SoilMigration to
ComponentGroundwater Portion of the Groundwater Ingestion Route (Class II Groundwater)
Chemical (totals)
(mg/kg)
pH 4.5 to
4.74
pH 4.75
to 5.24
pH 5.25
to 5.74
pH 5.75
to 6.24
pH 6.25
to 6.64
pH 6.65
to 6.89
pH 6.9
to 7.24
pH 7.25
to 7.74
pH 7.75
to 8.0
Inorganics
Antimony
20
20
20
20
20
20
20
20
20
Arsenic
100
100
100
110
110
120
120
120
120
Barium
260
490
850
1,200
1,500
1,600
1,700
1,800
2,100
Beryllium
140
260
420
820
2,800
7,900
17,000
130,000
1,000,000
Cadmium
10
17
27
37
52
75
110
590
4,300
Chromium (+6)
No Data
No Data
No Data
No Data
No Data
No Data
No Data
No Data
No Data
Copper
330
580
2,100
11,000
59,000
130,000
200,000
330,000
330,000
Cyanide
120
120
120
120
120
120
120
120
120
Mercury
0.05
0.06
0.14
0.75
4.4
10
16
32
40
Nickel
400
730
1,100
1,500
2,000
2,600
3,500
14,000
76,000
Selenium
24
17
12
8.8
6.3
5.2
4.5
3.3
2.4
Thallium
16
18
20
24
26
28
30
34
38
Zinc
2,000
3,600
5,200
7,200
10,000
12,000
15,000
32,000
110,000
Chemical (totals)
(mg/kg)
pH 4.5 to
4.74
pH 4.75
to 5.24
pH 5.25
to 5.74
pH 5.75
to 6.24
pH 6.25
to 6.64
pH 6.65
to 6.89
pH 6.9
to 7.24
pH 7.25
to 7.74
pH 7.75
to 8.0
Organics
Benzoic Acid
440
420
410
400
400
400
400
400
400
2-Chlorophenol
20
20
20
20
20
20
19
3.6
3.1
2,4-Dichlorophenol
1.0
1.0
1.0
1.0
1.0
1.0
1.0
0.86
0.69
Dinoseb
84
45
19
8.2
4.3
3.4
3.1
2.7
2.5
Pentachlorophenol
2.7
1.6
0.75
0.33
0.18
0.15
0.12
0.11
0.10
2,4,5-TP (Silvex)
130
79
62
57
55
55
55
55
55
2,4,5-Trichlorophenol
2,000
2,000
1,900
1,800
1,600
1,400
1,200
640
64
2,4,6-Trichlorophenol
0.37
0.36
0.34
0.26
0.20
0.15
0.13
0.09
0.07
Section 742.APPENDIX B:
Tier 1 Tables and Illustrations
TABLE E:
Tier 1 Groundwater Remediation Objectives for the Direct Ingestion of
Groundwater ComponentGroundwater Portion of the Groundwater Ingestion
Route
Groundwater
Remediation
Cleanup Objective
CAS No.
Chemical Name
Class I
(mg/L)
Class II
(mg/L)
83-32-9
Acenaphthene
0.42
2.1
67-64-1
Acetone
0.7
0.7
15972-60-8
Alachlor
0.002
c
0.01
c
116-06-3
Aldicarb
0.003
c
0.015
c
309-00-2
Aldrin
0.00004
a
0.0002
120-12-7
Anthracene
2.1
10.5
1912-24-9
Atrazine
0.003
c
0.015
c
71-43-2
Benzene
0.005
c
0.025
c
56-55-3
Benzo(
a
)anthracene
0.00013
a
0.00065
205-99-2
Benzo(
b
)fluoranthene
0.00018
a
0.0009
207-08-9
Benzo(
k
)fluroanthene
0.00017
a
0.00085
50-32-8
Benzo(
a
)pyrene
0.0002
a,c
0.002
c
111-44-4
Bis(2-chloroethyl)ether
0.01
a
0.01
117-81-7
Bis(2-ethylhexyl)phthalate
0.006
a,c
0.06
c
75-27-4
Bromodichloromethane
(Dichlorobromomethane)
0.00002
a
0.00002
75-25-2
Bromoform
0.0002
a
0.0002
71-36-3
Butanol
0.7
0.7
85-68-7
Butyl
benzyl phthalate
1.4
7.0
86-74-8
Carbazole
---
---
1563-66-2
Carbofuran
0.04
c
0.2
c
75-15-0
Carbon disulfide
0.7
3.5
56-23-5
Carbon tetrachloride
0.005
c
0.025
c
57-74-9
Chlordane
0.002
c
0.01
c
Groundwater
Remediation
Cleanup Objective
CAS No.
Chemical Name
Class I
(mg/L)
Class II
(mg/L)
108-90-7
Chlorobenzene
(Monochlorobenzene)
0.1
c
0.5
c
124-48-1
Chlorodibromomethane
(Dibromochloromethane)
0.14
0.14
67-66-3
Chloroform
0.00002
a
0.0001
218-01-9
Chrysene
0.0015
a
0.0075
94-75-7
2,4-D
0.07
c
0.35
c
75-99-0
Dalapon
0.2
c
2.0
c
72-54-8
DDD
0.00011
a
0.00055
72-55-9
DDE
0.00004
a
0.0002
50-29-3
DDT
0.00012
a
0.0006
53-70-3
Dibenzo(
a,h
)anthracene
0.0003
a
0.0015
96-12-8
1,2-Dibromo-3-chloropropane
0.0002
c
0.0002
c
106-93-4
1,2-Dibromoethane
(Ethylene
dibromide)
0.00005
a,c
0.0005
c
84-74-2
Di-
n
-butyl phthalate
0.7
3.5
95-50-1
1,2-Dichlorobenzene
(
o
-
Dichlorobenzene)
0.6
c
1.5
c
106-46-7
1,4-Dichlorobenzene
(
p
-
Dichlorobenzene)
0.075
c
0.375
c
91-94-1
3,3'-Dichlorobenzidine
0.02
a
0.1
75-34-3
1,1-Dichloroethane
0.7
3.5
107-06-2
1,2-Dichloroethane
(Ethylene dichloride)
0.005
c
0.025
c
75-35-4
1,1-Dichloroethylene
b
0.007
c
0.035
c
156-59-2
cis
-1,2-Dichloroethylene
0.07
c
0.2
c
156-60-5
trans
-1,2-Dichloroethylene
0.1
c
0.5
c
78-87-5
1,2-Dichloropropane
0.005
c
0.025
c
542-75-6
1,3-Dichloropropene
(1,3-Dichloropropylene,
cis
+
trans
)
0.001
a
0.005
Groundwater
Remediation
Cleanup Objective
CAS No.
Chemical Name
Class I
(mg/L)
Class II
(mg/L)
60-57-1
Dieldrin
0.00002
a
0.0001
84-66-2
Diethyl phthalate
5.6
5.6
121-14-2
2,4-Dinitrotoluene
a
0.00002
0.00002
606-20-2
2,6-Dinitrotoluene
a
0.0001
0.0001
88-85-7
Dinoseb
0.007
c
0.07
c
117-84-0
Di-
n
-octyl phthalate
0.14
0.7
115-29-7
Endosulfan
0.042
0.21
145-73-3
Endothall
0.1
c
0.1
c
72-20-8
Endrin
0.002
c
0.01
c
100-41-4
Ethylbenzene
0.7
c
1.0
c
206-44-0
Fluoranthene
0.28
1.4
86-73-7
Fluorene
0.28
1.4
76-44-8
Heptachlor
0.0004
c
0.002
c
1024-57-3
Heptachlor
epoxide
0.0002
c
0.001
c
118-74-1
Hexachlorobenzene
0.00006
a
0.0003
319-84-6
alpha
-HCH (
alpha
-BHC)
0.00003
a
0.00015
58-89-9
gamma
-HCH (Lindane)
0.0002
c
0.001
c
77-47-4
Hexachlorocyclopentadiene
0.05
c
0.5
c
67-72-1
Hexachloroethane
0.007
0.035
193-39-5
Indeno(1,2,3-
c,d
)pyrene
0.00043
a
0.00215
78-59-1
Isophorone
1.4
1.4
72-43-5
Methoxychlor
0.04
c
0.2
c
74-83-9
Methyl bromide
(Bromomethane)
0.0098
0.049
75-09-2
Methylene chloride
(Dichloromethane)
0.005
c
0.05
c
91-20-3
Naphthalene
2
0.025
0.039
98-95-3
Nitrobenzene
2
0.0035
0.0035
Groundwater
Remediation
Cleanup Objective
CAS No.
Chemical Name
Class I
(mg/L)
Class II
(mg/L)
1918-02-1
Picloram
0.5
c
5.0
c
1336-36-3
Polychlorinated
biphenyls (PCBs)
n
0.0005
c
0.0025
c
129-00-0
Pyrene
0.21
1.05
122-34-9
Simazine
0.004
c
0.04
c
100-42-5
Styrene
0.1
c
0.5
c
93-72-1
2,4,5-TP
(Silvex)
0.05
c
0.25
c
127-18-4
Tetrachloroethylene
(Perchloroethylene)
0.005
c
0.025
c
108-88-3
Toluene
1.0
c
2.5
c
8001-35-2
Toxaphene
0.003
c
0.015
c
120-82-1
1,2,4-Trichlorobenzene
0.07
c
0.7
c
71-55-6
1,1,1-Trichloroethane
2
0.2
c
1.0
c
79-00-5
1,1,2-Trichloroethane
0.005
c
0.05
c
79-01-6
Trichloroethylene
0.005
c
0.025
c
108-05-4
Vinyl acetate
7.0
7.0
75-01-4
Vinyl chloride
0.002
c
0.01
c
1330-20-7
Xylenes (total)
10.0
c
10.0
c
Ionizable Organics
65-85-0
Benzoic Acid
28
28
106-47-8
4-Chloroaniline
(p
-Chloroaniline)
0.028
0.028
95-57-8
2-Chlorophenol
0.035
0.175
120-83-2
2,4-Dichlorophenol
0.021
0.021
105-67-9
2,4-Dimethylphenol
0.14
0.14
51-28-5
2,4-Dinitrophenol
0.014
0.014
95-48-7
2-Methylphenol
(
o
- Cresol)
0.35
0.35
86-30-6
N
-Nitrosodiphenylamine
0.01
a
0.05
Groundwater
Remediation
Cleanup Objective
CAS No.
Chemical Name
Class I
(mg/L)
Class II
(mg/L)
621-64-7
N
-Nitrosodi-
n
-propylamine
0.01
a
0.01
87-86-5
Pentachlorophenol
0.001
a,c
0.005
c
108-95-2
Phenol
0.1
c
0.1
c
95-95-4
2,4,5-Trichlorophenol
0.7
3.5
88-06-2
2,4,6
Trichlorophenol
0.0064
a
0.032
Inorganics
7440-36-0
Antimony
0.006
c
0.024
c
7440-38-2
Arsenic
0.05
c
0.2
c
7440-39-3
Barium
2.0
c
2.0
c
7440-41-7
Beryllium
0.004
c
0.5
c
7440-42-8
Boron
2.0
c
2.0
c
7440-43-9
Cadmium
0.005
c
0.05
c
16887-00-6
Chloride
200
c
200
c
7440-47-3
Chromium, total
0.1
c
1.0
c
18540-29-9
Chromium, ion,
hexavalent
---
---
7440-48-4
Cobalt
1.0
c
1.0
c
7440-50-8
Copper
0.65
c
0.65
c
57-12-5
Cyanide
0.2
c
0.6
c
7782-41-4
Fluoride
4.0
c
4.0
c
15438-31-0
Iron
5.0
c
5.0
c
7439-92-1
Lead
0.0075
c
0.1
c
7439-96-5
Manganese
0.15
c
10.0
c
7439-97-6
Mercury
0.002
c
0.01
c
7440-02-0
Nickel
0.1
c
2.0
c
14797-55-8
Nitrate as N
10.0
c
100
c
7782-49-2
Selenium
0.05
c
0.05
c
7440-22-4
Silver
0.05
c
---
14808-79-8
Sulfate
400
c
400
c
Groundwater
Remediation
Cleanup Objective
CAS No.
Chemical Name
Class I
(mg/L)
Class II
(mg/L)
7440-28-0
Thallium
0.002
c
0.02
c
7440-62-2
Vanadium
2
0.049
---
7440-66-6
Zinc
5.0
c
10
c
Chemical Name and Groundwater
Remediation
Cleanup Objective Notations
a
The groundwater Health Advisory concentration is equal to ADL for carcinogens.
b
Oral Reference Dose and/or Reference Concentration under review by USEPA. Listed values subject to change.
c
Value listed is also the Groundwater Quality Standard for this che
mical pursuant to 35 Ill. Adm. Code 620.410 for
Class I Groundwater or 35 Ill. Adm. Code 620.420 for Class II Groundwater.
Section 742.APPENDIX B:
Tier 1 Tables and Illustrations
TABLE F:
Values Used to Calculate the Tier 1 Soil Remediation Objectives for the
SoilMigration to ComponentGroundwater Portion of the Groundwater Ingestion
Route
GW
obj
Concentration used to Calculate
Tier 1 Soil
Rememdiation
Objectives
a
CAS No.
Chemical Name
Class I
(mg/L)
Class II
(mg/L)
83-32-9
Acenaphthene
2.0
b
10
67-64-1
Acetone
4.0
b
4.0
15972-60-8
Alachlor
0.002
c
0.01
c
116-06-3
Aldicarb
0.003
c
0.015
c
309-00-2
Aldrin
5.0E-6
b
2.5E-5
120-12-7
Anthracene
10
b
50
1912-24-9
Atrazine
0.003
c
0.015
c
71-43-2
Benzene
0.005
c
0.025
c
56-55-3
Benzo(
a
)anthracene
0.0001
b
0.0005
205-99-2
Benzo(
b
)fluoranthene
0.0001
b
0.0005
207-08-9
Benzo(
k
)fluroanthene
0.001
b
0.005
50-32-8
Benzo(
a
)pyrene
0.0002
a,c
0.002
c
111-44-4
Bis(2-chloroethyl)ether
8.0E-5
b
8.0E-5
117-81-7
Bis(2-ethylhexyl)phthalate
0.006
a,c
0.06
c
75-27-4
Bromodichloromethane
(Dichlorobromomethane)
0.1
b
0.1
75-25-2
Bromoform
0.1
b
0.01
71-36-3
Butanol
4.0
b
4.0
85-68-7
Butyl
benzyl phthalate
7.0
b
35
86-74-8
Carbazole
0.004
b
0.02
1563-66-2
Carbofuran
0.04
c
0.2
c
75-15-0
Carbon disulfide
4.0
b
20
56-23-5
Carbon tetrachloride
0.005
c
0.025
c
57-74-9
Chlordane
0.002
c
0.01
c
GW
obj
Concentration used to Calculate
Tier 1 Soil
Rememdiation
Objectives
a
CAS No.
Chemical Name
Class I
(mg/L)
Class II
(mg/L)
108-90-7
Chlorobenzene
(Monochlorobenzene)
0.1
c
0.5
c
124-48-1
Chlorodibromomethane
(Dibromochloromethane)
0.06
b
0.06
67-66-3
Chloroform
0.1
b
0.5
218-01-9
Chrysene
0.1
b
0.05
94-75-7
2,4-D
0.07
c
0.35
c
75-99-0
Dalapon
0.2
c
2.0
c
72-54-8
DDD
0.0004
b
0.002
72-55-9
DDE
0.0003
b
0.0015
50-29-3
DDT
0.0003
b
0.0015
53-70-3
Dibenzo(
a,h
)anthracene
1.0E-5
b
5.0E-5
96-12-8
1,2-Dibromo-3-chloropropane
0.0002
c
0.0002
c
106-93-4
1,2-Dibromoethane
(Ethylene
dibromide)
0.00005
a,c
0.0005
c
84-74-2
Di-
n
-butyl phthalate
4.0
b
20
95-50-1
1,2-Dichlorobenzene
(
o
-
Dichlorobenzene)
0.6
c
1.5
c
106-46-7
1,4-Dichlorobenzene
(
p
-
Dichlorobenzene)
0.075
c
0.375
c
91-94-1
3,3'-Dichlorobenzidine
0.0002
b
0.001
75-34-3
1,1-Dichloroethane
4.0
b
20
107-06-2
1,2-Dichloroethane
(Ethylene dichloride)
0.005
c
0.025
c
75-35-4
1,1-Dichloroethylene
0.007
c
0.035
c
156-59-2
cis
-1,2-Dichloroethylene
0.07
c
0.2
c
156-60-5
trans
-1,2-Dichloroethylene
0.1
c
0.5
c
78-97-5
1,2-Dichloropropane
0.005
c
0.025
c
542-75-6
1,3-Dichloropropene
(1,3-Dichloropropylene,
cis
+
trans
)
0.0005
b
0.0025
GW
obj
Concentration used to Calculate
Tier 1 Soil
Rememdiation
Objectives
a
CAS No.
Chemical Name
Class I
(mg/L)
Class II
(mg/L)
60-57-1
Dieldrin
5.0E-6
b
2.5E-5
84-66-2
Diethyl phthalate
30
b
30
121-14-2
2,4-Dinitrotoluene
0.0001
b
0.0001
606-20-2
2,6-Dinitrotoluene
0.0001
0.0001
88-85-7
Dinoseb
0.007
c
0.07
c
117-84-0
Di-
n
-octyl phthalate
0.7
b
3.5
115-29-7
Endosulfan
0.2
b
1.0
145-73-3
Endothall
0.1
c
0.1
c
72-20-8
Endrin
0.002
c
0.01
c
100-41-4
Ethylbenzene
0.7
c
1.0
c
206-44-0
Fluoranthene
1.0
b
5.0
86-73-7
Fluorene
1.0
b
5.0
76-44-8
Heptachlor
0.0004
c
0.002
c
1024-57-3
Heptachlor
epoxide
0.0002
c
0.001
c
118-74-1
Hexachlorobenzene
0.001
b
0.005
319-84-6
alpha
-HCH (
alpha
-BHC)
1.0E-5
b
5.0E-5
58-89-9
gamma
-HCH (Lindane)
0.0002
c
0.001
c
77-47-4
Hexachlorocyclopentadiene
0.05
c
0.5
c
67-72-1
Hexachloroethane
0.007
0.035
193-39-5
Indeno(1,2,3-
c,d
)pyrene
0.0001
b
0.0005
78-59-1
Isophorone
1.4
1.4
72-43-5
Methoxychlor
0.04
c
0.2
c
74-83-9
Methyl bromide
(Bromomethane)
0.05
b
0.25
75-09-2
Methylene chloride
(Dichloromethane)
0.005
c
0.05
c
91-20-3
Naphthalene
1.0
b
5.0
98-95-3
Nitrobenzene
0.02
b
0.02
GW
obj
Concentration used to Calculate
Tier 1 Soil
Rememdiation
Objectives
a
CAS No.
Chemical Name
Class I
(mg/L)
Class II
(mg/L)
1918-02-1
Picloram
0.5
c
5.0
c
1336-36-3
Polychlorinated
biphenyls (PCBs)
---
---
129-00-0
Pyrene
1.0
b
5.0
122-34-9
Simazine
0.004
c
0.04
c
100-42-5
Styrene
0.1
c
0.5
c
93-72-1
2,4,5-TP
(Silvex)
0.05
c
0.25
c
127-18-4
Tetrachloroethylene
(Perchloroethylene)
0.005
c
0.025
c
108-88-3
Toluene
1.0
c
2.5
c
8001-35-2
Toxaphene
0.003
c
0.015
c
120-82-1
1,2,4-Trichlorobenzene
0.07
c
0.7
c
71-55-6
1,1,1-Trichloroethane
2
0.2
c
1.0
c
79-00-5
1,1,2-Trichloroethane
0.005
c
0.05
c
79-01-6
Trichloroethylene
0.005
c
0.025
c
108-05-4
Vinyl acetate
40
b
40
75-01-4
Vinyl chloride
0.002
c
0.01
c
1330-20-7
Xylenes (total)
10.0
c
10.0
c
Ionizable Organics
65-85-0
Benzoic Acid
100
b
100
106-47-8
4-Chloroaniline
(p
-Chloroaniline)
0.1
b
0.1
95-57-8
2-Chlorophenol
0.2
b
1.0
120-83-2
2,4-Dichlorophenol
0.1
b
0.1
105-67-9
2,4-Dimethylphenol
0.7
b
0.7
51-28-5
2,4-Dinitrophenol
0.04
b
0.04
95-48-7
2-Methylphenol
(
o
- Cresol)
2.0
b
2.0
86-30-6
N
-Nitrosodiphenylamine
0.02
b
0.1
GW
obj
Concentration used to Calculate
Tier 1 Soil
Rememdiation
Objectives
a
CAS No.
Chemical Name
Class I
(mg/L)
Class II
(mg/L)
621-64-7
N
-Nitrosodi-
n
-propylamine
1.0E-5
b
1.0E-5
87-86-5
Pentachlorophenol
0.001
a,c
0.005
c
108-95-2
Phenol
0.1
c
0.1
c
95-95-4
2,4,5-Trichlorophenol
4.0
b
20
88-06-2
2,4,6
Trichlorophenol
0.008
b
0.04
Inorganics
7440-36-0
Antimony
0.006
c
0.024
c
7440-38-2
Arsenic
0.05
c
0.2
c
7440-39-3
Barium
2.0
c
2.0
c
7440-41-7
Beryllium
0.004
c
0.5
c
7440-42-8
Boron
2.0
c
2.0
c
7440-43-9
Cadmium
0.005
c
0.05
c
16887-00-6
Chloride
200
c
200
c
7440-47-3
Chromium, total
0.1
c
1.0
c
18540-29-9
Chromium, ion,
hexavalent
---
---
7440-48-4
Cobalt
1.0
c
1.0
c
7440-50-8
Copper
0.65
c
0.65
c
57-12-5
Cyanide
0.2
c
0.6
c
7782-41-4
Fluoride
4.0
c
4.0
c
15438-31-0
Iron
5.0
c
5.0
c
7439-92-1
Lead
0.0075
c
0.1
c
7439-96-5
Manganese
0.15
c
10.0
c
7439-97-6
Mercury
0.002
c
0.01
c
7440-02-0
Nickel
0.1
c
2.0
c
14797-55-8
Nitrate as N
10.0
c
100
c
7782-49-2
Selenium
0.05
c
0.05
c
7440-22-4
Silver
0.05
c
---
14808-79-8
Sulfate
400
c
400
c
GW
obj
Concentration used to Calculate
Tier 1 Soil
Rememdiation
Objectives
a
CAS No.
Chemical Name
Class I
(mg/L)
Class II
(mg/L)
7440-28-0
Thallium
0.002
c
0.02
c
7440-62-2
Vanadium
0.049
---
7440-66-6
Zinc
5.0
c
10
c
Chemical Name and Groundwater
Remediation
Cleanup Objective Notations
a
The Equation S17 is used to calculate the Soil Remediation Objective for the
Soil
Migration to
ComponentGroundwater portion
of the Groundwater Ingestion Route; this equation requires calculation of the
Target Soil Leachate Concentration (
C
w
) from Equation S18:
C
w
= DF x
GW
obj
.
b
Value listed is the Water Health Based Limit (HBL) for this chemical from Soil Screening Guidance: User’s Guide,
incorporated by reference at Section 742.210; for carcinogens, the HBL is equal to a cancer risk of 1.0E-6, and
for noncarcinogens is equal to a Hazard Quotient of 1.0. NOTE: These
GW
obj
concentrations are not equal to
the Tier 1 Groundwater Remediation Objectives for the Direct Ingestion of
Groundwater
ComponentGroundwater
portion
of the Groundwater Ingestion Route, listed in Section 742.Appendix B, Table E.
c
Value listed is also the Groundwater Quality Standard for this chemical pursuant to 35 Ill. Adm. Code 620.410 for
Class I Groundwater or 35 Ill. Adm. Code 620.420 for Class II Groundwater.
Section 742.APPENDIX B:
Tier 1 Tables and Illustrations
Illustration A: Tier 1 Evaluation
Site
Characterization
Agricultural or
Conservation
Receptors
Tier 3
Evaluation
Residential Property
Appendix B, Table A
and Table E
Objectives
Industrial or
Commercial Property
Appendix B, Table B
and Table E
Objectives
Appendix B, Tables C & D
Soil pH determination if COC's
have pH dependent solubility
(Optional)
Determine Tier 1 remediation
objectives
(i.e., most restrictive value
from the three exposure
routes)
Compare site data to remediation objectives
and determine:
1. Which COC's are below the Tier 1 objectives
2. Which COC's are still of concern
3. Can soil averaging or compositing be used
Remediate to
Tier 1
objectives
Tier 2 evaluation for
all COC's not
eliminated in all
applicable pathways
Tier 3 evaluation
for various
situations
No Further Remediation
if all COC'c are eliminated
(Institutional controls required for
industrial/commercial objectives)
Section 742.APPENDIX C:
Tier 2 Tables and Illustrations
Table A:
SSL Equations
Equations for Soil
Ingestion Exposure
Route
Remediation Objectives for
Noncarcinogenic
Contaminants
(mg/kg)
THQ
BW
AT
d
yr
RfDo
kg
mg
EF
ED
IR
soil
•
•
•
•
−
•
•
•
365
1
10
6
S1
Remediation Objectives for
Carcinogenic Contaminants -
Residential
(mg/kg)
TR
AT
d
yr
SF
kg
mg
EF
IF
c
o
soil
adj
•
•
•
•
•
−
−
365
10
6
S2
Remediation Objectives for
Carcinogenic
Contaminants - Industrial/
Commercial, Construction
Worker
(mg/kg)
TR
BW
AT
d
yr
SF
kg
mg
EF
ED
IR
c
o
soil
•
•
•
•
•
•
•
−
365
10
6
S3
Equations for
Inhalation Exposure
Route (Volatiles)
Remediation Objectives for
Noncarcinogenic
Contaminants - Residential,
Industrial/Commercial
(mg/kg)
THQ
AT
d
yr
EF
ED
RfC
VF
•
•
•
•
•
365
1
1
S4
Remediation Objectives for
Noncarcinogenic
Contaminants - Construction
Worker (mg/kg)
THQ
AT
d
yr
EF
ED
RfC
VF
•
•
•
•
•
365
1
1
'
S5
Remediation Objectives for
Carcinogenic Contaminants -
Residential, Industrial/
Commercial (mg/kg)
TR
AT
d
yr
URF
ug
mg
EF
ED
VF
c
•
•
•
•
•
•
365
1 000
1
,
S6
Remediation Objectives for
Carcinogenic Contaminants -
Construction Worker
(mg/kg)
TR
AT
d
yr
URF
ug
mg
EF
ED
VF
c
•
•
•
•
•
•
365
1 000
1
,
'
S7
Equation for Derivation of
the Volatilization Factor -
Residential, Industrial/
Commercial, VF (m
3
/kg)
(
)
(
)
VF
Q
C
DA
T
b
DA
m
cm
=
•
•
•
•
•
•
−
314
1 2
2
10
4
2
2
.
/
r
S8
Equation for Derivation of
the Volatilization Factor -
Construction Worker, VF
′
(m
3
/kg)
VF
VF
′ =
10
S9
Equation for Derivation
of Apparent Diffusivity, D
A
(cm
2
/s)
(
)
(
)
(
)
(
)
DA
a
Di
H
w
Dw
b
K
d
w
a
H
=
•
•
+
•
•
•
+
+
•
q
q
r
q
q
3 33
333
2
1
.
'
.
'
η
S10
Equations for
Inhalation Exposure
Route (Fugitive
Dusts)
Remediation Objectives for
Noncarcinogenic
Contaminants - Residential,
Industrial/Commercial
(mg/kg)
THQ
AT
d
yr
EF
ED
RfC
PEF
•
•
•
•
•
365
1
1
S11
Remediation Objectives for
Noncarcinogenic
Contaminants - Construction
Worker (mg/kg)
THQ
AT
d
yr
EF
ED
RfC
PEF
•
•
•
•
•
365
1
1
'
S12
Remediation Objectives for
Carcinogenic Contaminants -
Residential, Industrial/
Commercial (mg/kg)
TR
ATc
d
yr
URF
ug
mg
EF
ED
PEF
•
•
•
•
•
•
365
1 000
1
,
S13
Remediation Objectives for
Carcinogenic Contaminants -
Construction Worker
(mg/kg)
TR
AT
c
d
yr
URF
ug
mg
EF
ED
PEF
•
•
•
•
•
•
365
1 000
1
,
'
S14
Equation for Derivation of
Particulate Emission Factor,
PEF (m
3
/kg)
(
)
PEF
Q
C
s
hr
V
Um
Ut
F
x
=
•
•
−
•
•
3 600
0 036
1
3
,
.
(
)
S15
Equation for Derivation of
Particulate Emission Factor,
PEF
′
- Construction Worker
(m
3
/kg)
PEF
PEF
'
=
10
NOTE: PEF must be the industrial/commercial value
S16
Equations for the
SoilMigration to
ComponentGroundwa
ter Portion of the
Groundwater
Ingestion Exposure
Route
Remediation Objective
(mg/kg)
(
)
C
K
H
w
d
w
a
b
•
+
+
•
′
q
q
r
NOTE: This equation can only be used to model contaminant migration not in the
water bearing unit.
S17
Target Soil Leachate
Concentration, C
w
(mg/L)
C
DF
GW
w
obj
=
•
S18
Soil-Water Partition
Coefficient, K
d
(cm
3
/g)
K
K
f
d
oc
oc
=
•
S19
Water-Filled Soil Porosity,
θ
w
(L
water
/L
soil
)
q
h
w
s
b
I
K
=
•
+
1
2
3)
/(
S20
Air-Filled Soil Porosity,
θ
a
(L
air
/L
soil
)
q
h
q
a
w
=
−
S21
Dilution Factor, DF
(unitless)
DF
K
i
d
I
L
=
+
•
•
•
1
S22
Groundwater Remediation
Objective for Carcinogenic
Contaminants, GW
obj
(mg/L)
TR
BW
AT
d
yr
SF
IR
EF
ED
c
o
w
•
•
•
•
•
•
365
S23
Total Soil Porosity,
η
(L
pore
/L
soil
)
h
r
r
=
−
1
b
s
S24
Equation for Estimation of
Mixing Zone Depth, d
(m)
(
)
(
)
(
)
d
L
d
L
I
K
i
d
a
a
=
•
+
−
−
•
•
•
0 0112
1
2
0 5
.
exp
.
S25
Mass-Limit
Equations for
Inhalation Exposure
Route and
SoilMigration to
ComponentGroundwa
ter Portion of the
Groundwater
Ingestion Exposure
Route
Mass-Limit Volatilization
Factor for the Inhalation
Exposure Route -
Residential, Industrial/
Commercial, VF (m
3
/kg)
VF
Q
C
T
s
yr
b
ds
g
mg
M
L
M
L
−
−
=
•
•
•
•
•
315
10
7
10
6
.
r
NOTE: This equation may be used when area and depth of contaminant source are
known or can be estimated reliably.
S26
Mass-Limit Volatilization
Factor for Inhalation
Exposure Route -
Construction Worker, VF
′
-
(m
3
/kg)
VF
VF
M
L
M
L
−
−
=
'
10
S27
Mass-Limit Remediation
Objective for SoilMigration
to ComponentGroundwater
Portion of the Groundwater
Ingestion Exposure Route
(mg/kg)
(
)
Cw
I M
L
EDM
L
b
ds
•
−
•
−
•
r
NOTE: This equation may be used when area and depth of contaminant source are
known or can be estimated reliably.
S28
Equation for Derivation of the Soil Saturation Limit,
C
sat
(
)
(
)
[
]
C
S
K
H
sat
b
d
b
w
a
=
•
•
+
+
′ •
r
r
q
q
S29
Section 742.APPENDIX C:
Tier 2 Tables and Illustrations
Table B:
SSL Parameters
Symbol
Parameter
Units
Source
Parameter Value(s)
AT
Averaging Time for
Noncarcinogens in
Ingestion Equation
yr
Residential = 6
Industrial/Commercial = 25
Construction Worker = 0.115
AT
Averaging Time for
Noncarcinogens in
Inhalation Equation
yr
Residential = 30
Industrial/Commercial = 25
Construction Worker = 0.115
AT
c
Averaging Time for
Carcinogens
yr
SSL
70
BW
Body Weight
kg
Residential = 15, noncarcinogens
70, carcinogens
Industrial/Commercial = 70
Construction Worker = 70
C
sat
Soil Saturation
Concentration
mg/kg
Appendix A, Table A or
Equation S29 in
Appendix C, Table A
Chemical-Specific or
Calculated Value
C
w
Target Soil Leachate
Concentration
mg/L
Equation S18 in
Appendix C, Table A
Groundwater Standard, Health Advisory
concentration, or
Calculated Value
d
Mixing Zone Depth
m
SSL or
Equation S25 in
Appendix C, Table A
2 m or
Calculated Value
d
a
Aquifer Thickness
m
Field Measurement
Site-Specific
Symbol
Parameter
Units
Source
Parameter Value(s)
d
s
Depth of Source
m
Field Measurement or
Estimation
Site-Specific
D
A
Apparent Diffusivity
cm
2
/s
Equation S10 in
Appendix C, Table A
Calculated Value
D
i
Diffusivity in Air
cm
2
/s
Appendix C, Table E
Chemical-Specific
D
w
Diffusivity in Water
cm
2
/s
Appendix C, Table E
Chemical-Specific
DF
Dilution Factor
unitless
Equation S22 in
Appendix C, Table A
20 or Calculated Value
ED
Exposure Duration for
Ingestion of
Carcinogens
yr
Industrial/Commercial = 25
Construction Worker = 1
ED
Exposure Duration for
Inhalation of
Carcinogens
yr
Residential = 30
Industrial/Commercial = 25
Construction Worker = 1
ED
Exposure Duration for
Ingestion of
Noncarcinogens
yr
Residential = 6
Industrial/Commercial = 25
Construction Worker = 1
ED
Exposure Duration for
Inhalation of
Noncarcinogens
yr
Residential = 30
Industrial/Commercial = 25
Construction Worker = 1
ED
Exposure Duration for
the Direct Ingestion of
Groundwater
yr
Residential = 30
Industrial/Commercial = 25
Construction Worker = 1
Symbol
Parameter
Units
Source
Parameter Value(s)
ED
M-L
Exposure Duration for
Migration to
Groundwater Mass-
Limit Equation S28
yr
SSL
70
EF
Exposure Frequency
d/yr
Residential = 350
Industrial/Commercial = 250
Construction Worker = 30
F(x)
Function dependent on
U
m
/U
t
unitless
SSL
0.194
f
oc
Organic Carbon
Content of Soil
g/g
SSL or
Field Measurement
(See Appendix C, Table F)
Surface Soil = 0.006
Subsurface soil = 0.002, or
Site-Specific
GW
obj
Groundwater Cleanup
Objective
mg/L
Appendix B, Table E,
35 IAC 620.Subpart F, or
Equation S23 in
Appendix C, Table A
Chemical-Specific or Calculated
H'
Henry's Law Constant
unitless
Appendix C, Table E
Chemical-Specific
i
Hydraulic Gradient
m/m
Field Measurement
(See Appendix C, Table F)
Site-Specific
I
Infiltration Rate
m/yr
SSL
0.3
I
M-L
Infiltration Rate for
Migration to
Groundwater Mass-
Limit Equation S28
m/yr
SSL
0.18
Symbol
Parameter
Units
Source
Parameter Value(s)
IF
soil-adj
(residential)
Age Adjusted Soil
Ingestion Factor for
Carcinogens
(mg-yr)/(kg-d)
SSL
Residential = 114
IR
soil
Soil Ingestion Rate
mg/d
Residential = 200
Industrial/Commercial = 50
Construction Worker = 480
IR
W
Daily Water Ingestion
Rate
L/d
Residential = 2
Industrial/Commercial = 1
K
Aquifer Hydraulic
Conductivity
m/yr
Field Measurement
(See Appendix C, Table F)
Site-Specific
K
d
Soil-Water Partition
Coefficient
cm
3
/g or L/kg
Equation S19 in
Appendix C, Table A
Calculated Value
K
oc
Organic Carbon
Partition Coefficient
cm
3
/g or L/kg
Appendix C, Table E
or Appendix C, Table I
Chemical-Specific
K
s
Saturated Hydraulic
Conductivity
m/yr
Appendix C, Table K
Appendix C, Illustration C
Site-Specific
L
Source Length Parallel
to Groundwater Flow
m
Field Measurement
Site-Specific
PEF
Particulate Emission
Factor
m
3
/kg
SSL or Equation S15 in
Appendix C, Table A
Residential = 1.32
•
10
9
or Site-Specific
Industrial/Commercial = 1.24
•
10
9
or
Site-Specific
PEF
′
Particulate Emission
Factor adjusted for
Agitation (construction
worker)
m
3
/kg
Equation S16 in Appendix
C, Table A using PEF
(industrial/commercial)
1.24
•
10
8
or Site-Specific
Symbol
Parameter
Units
Source
Parameter Value(s)
Q/C
(used in VF equations)
Inverse of the mean
concentration at the
center of a square
source
(g/m
2
-s)/(kg/m
3
)
Appendix C, Table H
Residential = 68.81
Industrial/Commercial = 85.81
Construction Worker = 85.81
Q/C
(used in PEF
equations)
Inverse of the mean
concentration at the
center of a square
source
(g/m
2
-s)/(kg/m
3
)
SSL or Appendix C, Table
H
Residential = 90.80
Industrial/Commercial = 85.81
Construction Worker = 85.81
RfC
Inhalation Reference
Concentration
mg/m
3
IEPA (IRIS/HEAST
a
)
Toxicological-Specific
(Note: for Construction Workers use
subchronic reference concentrations)
RfD
o
Oral Reference Dose
mg/(kg-d)
IEPA (IRIS/HEAST
a
)
Toxicological-Specific
(Note: for Construction Worker use
subchronic reference doses)
S
Solubility in Water
mg/L
Appendix C, Table E
Chemical-Specific
SF
o
Oral Slope Factor
(mg/kg-d)
-1
IEPA (IRIS/HEAST
a
)
Toxicological-Specific
T
Exposure Interval
s
Residential = 9.5
•
10
8
Industrial/Commercial = 7.9
•
10
8
Construction Worker = 3.6
•
10
6
T
M-L
Exposure Interval for
Mass-Limit
Volatilization Factor
Equation S26
yr
SSL
30
THQ
Target Hazard
Quotient
unitless
SSL
1
Symbol
Parameter
Units
Source
Parameter Value(s)
TR
Target Cancer Risk
unitless
Residential = 10
-6
at the point of human
exposure
Industrial/Commercial = 10
-6
at the point
of human exposure
Construction Worker = 10
-6
at the point
of human exposure
U
m
Mean Annual
Windspeed
m/s
SSL
4.69
URF
Inhalation Unit Risk
Factor
(ug/m
3
)
-1
IEPA (IRIS/HEAST
a
)
Toxicological-Specific
U
t
Equivalent Threshold
Value of Windspeed at
7 m
m/s
SSL
11.32
V
Fraction of Vegetative
Cover
unitless
SSL or Field Measurement
0.5 or Site-Specific
VF
Volatilization Factor
m
3
/kg
Equation S8 in
Appendix C, Table A
Calculated Value
VF
′
Volatilization Factor
adjusted for Agitation
m
3
/kg
Equation S9 in
Appendix C, Table A
Calculated Value
VF
M-L
Mass-Limit
Volatilization Factor
m
3
/kg
Equation S26 in
Appendix C, Table A
Calculated Value
VF
′
M-L
Mass-Limit
Volatilization Factor
adjusted for Agitation
m
3
/kg
Equation S27 in
Appendix C, Table A
Calculated Value
Symbol
Parameter
Units
Source
Parameter Value(s)
η
Total Soil Porosity
L
pore
/L
soil
SSL or
Equation S24 in
Appendix C, Table A
0.43, or
Gravel = 0.25
Sand = 0.32
Silt = 0.40
Clay = 0.36, or
Calculated Value
θ
a
Air-Filled Soil Porosity
L
air
/L
soil
SSL or
Equation S21 in
Appendix C, Table A
Surface Soil (top 1 meter) = 0.28
Subsurface Soil (below 1 meter) = 0.13,
or
Gravel = 0.05
Sand = 0.14
Silt - 0.24
Clay = 0.19, or
Calculated Value
θ
w
Water-Filled Soil
Porosity
L
water
/L
soil
SSL or
Equation S20 in
Appendix C, Table A
Surface Soil (top 1 meter) = 0.15
Subsurface Soil (below 1 meter) = 0.30,
or
Gravel = 0.20
Sand = 0.18
Silt = 0.16
Clay = 0.17, or
Calculated Value
Symbol
Parameter
Units
Source
Parameter Value(s)
ρ
b
Dry Soil Bulk Density
kg/L or g/cm
3
SSL or
Field Measurement
(See Appendix C, Table F)
1.5, or
Gravel = 2.0
Sand = 1.8
Silt = 1.6
Clay = 1.7, or
Site-Specific
ρ
s
Soil Particle Density
g/cm
3
SSL or
Field Measurement
(See Appendix C, Table F)
2.65, or
Site-Specific
ρ
w
Water Density
g/cm
3
SSL
1
1/(2b+3)
Exponential in
Equation S20
unitless
Appendix C, Table K
Appendix C, Illustration C
Site-Specific
a
HEAST = Health Effects Assessment Summary Tables. USEPA, Office of Solid Waste and Emergency Response. EPA/SQO/R-95/036. Updated Quarterly.
Section 742.Appendix C:
Tier 2 Tables and Illustrations
Table C:
RBCA Equations
Equations for
the combined
exposures
routes of soil
ingestion
Remediation
Objectives for
Carcinogenic
Contaminants
(mg/kg)
(
)
(
)
(
)
TR
BW
ATc
d
yr
EF
ED
SF
kg
mg
IR
RAF
SA
M
RAF
SF
IR
VF
VF
o
soil
o
d
i
air
ss
p
•
•
•
•
•
•
•
•
+
•
•
+
•
•
+
−
?
365
10
6
R1
inhalation of
vapors and
particulates,
and dermal
contact with
soil
Remediation
Objectives for Non-
carcinogenic
Contaminants
(mg/kg)
(
)
(
)
[
]
THQ
BW
AT
n
d
yr
EF
ED
kg
mg
IR
RAF
SA
M
RAF
RfD
IR
VF
ss
VF
p
RfD
soil
o
d
o
air
i
•
•
•
•
•
•
+
•
•
+
•
+
−
365
10
6
R2
Volatilization Factor
for Surficial Soils,
VF
ss
(kg/m
3
)
Whichever is less
between R3 and R4
(
)
(
)
[
]
W
cm
m
g
D
H
H
s
air
s
eff
s
s
•
•
⋅
⋅
•
•
•
+
+
′
•
10
3
3
3
r
d
p
q
r
q
t
R3
VF
W
d
cm
kg
m
g
U
ss
s
air
air
=
•
•
•
⋅
⋅
•
•
r
d
t
10
3
3
3
R4
Volatilization Factor
for Surficial Soils
Regarding
Particulates, VF
p
(kg/m
3
)
VF
P
W
cm
kg
m
g
U
p
e
air
air
=
•
•
⋅
⋅
•
10
3
3
3
d
R5
Effective Diffusion
Coefficient in Soil
Based on Vapor-
Phase Concentration
D
s
eff
(cm
2
/s)
D
D
D
H
s
eff
air
as
T
water
ws
T
=
•
+
•
′•
q
q
q
q
3 33
2
3 33
2
.
.
R6
Equations for
the ambient
vapor
inhalation
(outdoor)
Remediation
Objectives for
Carcinogenic
Contaminants
(mg/kg)
RBSL
VF
air
samb
•
−
10
3
R7
route from
subsurface
soils
Remediation
Objectives for Non-
carcinogenic
Contaminants
(mg/kg)
RBSL
VF
air
samb
•
−
10
3
R8
Carcinogenic Risk-
Based Screening
Level for Air,
RBSL
air
(ug/m
3
)
RBSL
TR
BW
AT
d
yr
ug
mg
SF
IR
EF
ED
air
c
i
air
=
•
•
•
•
•
•
•
365
10
3
R9
Noncarcinogenic
Risk-Based
Screening Level for
Air, RBSL
air
(ug/m
3
)
RBSL
THQ
RfD
BW
AT
d
yr
ug
mg
IR
EF
ED
air
i
n
air
=
•
•
•
•
•
•
•
365
10
3
R10
Volatilization Factor
- Subsurface Soil to
Ambient Air, VF
samb
(mg/m
3
)/(mg/kg
soil
)
(
)
(
)
[
]
(
)
(
)
VF
H
cm
kg
m
g
k
H
U
L
D
W
samb
s
ws
s
s
as
air
air
s
s
eff
=
′•
•
⋅
⋅
+
•
+
′•
•
+
•
•
•
r
q
r
q
d
10
1
3
3
3
R11
Equations for
the
SoilMigration
to
ComponentGr
oundwater
Portion of the
Groundwater
Remediation
Objective
(mg/kg)
GW
LF
source
sw
NOTE: This equation can only be used to model contaminant migration not in the
water bearing unit.
R12
Ingestion
Exposure
Route
Groundwater at the
source, GW
source
(mg/L)
(
)
GW
GW
C
C
source
comp
x
source
=
R13
Leaching Factor,
LF
sw
(mg/L
water
)/(mg/kg
soil
)
(
)
(
)
[
]
(
)
(
)
LF
cm
kg
L
g
k
H
U
I
W
sw
s
ws
s
s
as
gw
gw
=
•
⋅
⋅
+
•
+
′ •
•
+
•
•
r
q
r
q
d
3
1
R14
Steady-State
Attenuation Along
the Centerline of a
Dissolved Plume,
C
(x)
/C
source
(
)
C
C
X
U
erf
S
X
erf
S
X
x
source
x
x
w
y
d
z
=
•
−
+
•
•
•
•
•
•
•
exp
2
1
1
4
4
2
a
l a
a
a
NOTE:
1. This equation does not predict the contaminant flow within bedrock.
2. If the value of the First Order Degradation Constant (
λ
) is not readily available, then set
λ
= 0.
R15
Longitudinal
Dispersivity,
α
x
(cm)
a
x
X
=
•
010
.
R16
Transverse
Dispersivity,
α
y
(cm)
a
a
y
x
=
3
R17
Vertical
Dispersivity,
α
z
(cm)
a
a
z
x
=
20
R18
Specific Discharge,
U
(cm/d)
U
K
i
T
=
•
q
R19
Soil-Water Sorption
Coefficient, k
s
k
K
f
s
oc
oc
=
•
R20
Volumetric Air
Content in Vadose
Zone Soils,
θ
as
(cm
3
air
/cm
3
soil
)
(
)
q
q
r
r
as
T
s
w
w
=
−
•
R21
Volumetric Water
Content in Vadose
Zone Soils,
θ
ws
(cm
3
water
/cm
3
soil
)
q
r
r
ws
s
w
w
=
•
R22
Total Soil Porosity,
θ
T
(cm
3
/cm
3
soil
)
q
q
q
T
as
ws
=
+
R23
Groundwater Darcy
Velocity, U
gw
(cm/yr)
U
K
i
gw
=
•
R24
Equations for
the
Groundwater
Ingestion
Exposure
Route
Remediation
Objective for
Carcinogenic
Contaminants
(mg/L)
TR
BW
AT
d
yr
SF
IR
EF
ED
c
o
w
•
•
•
•
•
•
365
R25
Dissolved
Hydrocarbon
Concentration along
Centerline, C
(x)
(g/cm
3
water
)
C
x
Csource
X
x
x
U
erf
Sw
y
X
erf
Sd
z
X
(
)
exp
=
•
•
−
+
•
•
•
•
•
•
•
2
1
1
4
4
2
a
l
a
a
a
NOTE:
1.
This equation does not predict the contaminant flow within bedrock.
2.
If the value of the First Order Degradation Constant (
λ
) is not readily available, then set
λ
= 0.
R26
Section 742.APPENDIX C:
Tier 2 Tables and Illustrations
Table D:
RBCA Parameters
Symbol
Parameter
Units
Source
Parameter Value(s)
AT
c
Averaging Time for
Carcinogens
yr
RBCA
70
AT
n
Averaging Time for
Noncarcinogens
yr
RBCA
Residential = 30
Industrial/Commercial = 25
Construction Worker = 0.115
BW
Adult Body Weight
kg
RBCA
70
C
source
The greatest potential
concentration of the
contaminant of concern in the
groundwater at the source of
the contamination, based on
the concentrations of
contaminants in groundwater
due to the release and the
projected concentration of the
contaminant migrating from
the soil to the groundwater.
mg/L
Field Measurement
Site-Specific
C
(x)
Concentration of Contaminant
in Groundwater at Distance X
from the source
mg/L
Equation R26 in
Appendix C, Table C
Calculated Value
Symbol
Parameter
Units
Source
Parameter Value(s)
C
(x)
/C
source
Steady-State Attenuation
Along the Centerline of a
Dissolved Plume
unitless
Equation R15 in
Appendix C, Table C
Calculated Value
d
Lower Depth of Surficial Soil
Zone
cm
Field Measurement
100 or
Site-Specific (not to exceed 100)
D
air
Diffusion Coefficient in Air
cm
2
/s
Appendix C, Table E
Chemical-Specific
D
water
Diffusion Coefficient in Water
cm
2
/s
Appendix C, Table E
Chemical-Specific
D
s
eff
Effective Diffusion Coefficient
in Soil Based on Vapor-Phase
Concentration
cm
2
/s
Equation R6 in
Appendix C, Table C
Calculated Value
ED
Exposure Duration
yr
RBCA
Residential = 30
Industrial/Commercial = 25
Construction Worker = 1
EF
Exposure Frequency
d/yr
RBCA
Residential = 350
Industrial/Commercial = 250
Construction Worker = 30
erf
Error Function
unitless
Appendix C, Table G
Mathematical Function
Symbol
Parameter
Units
Source
Parameter Value(s)
f
oc
Organic Carbon Content of
Soil
g/g
RBCA or
Field Measurement
(See Appendix C, Table F)
Surface Soil = 0.006
Subsurface Soil = 0.002 or
Site-Specific
GW
comp
Groundwater Objective at the
Compliance Point
mg/L
Appendix B, Table E,
35 IAC 620.Subpart F, or
Equation R25 in Appendix C, Table
C
Site-Specific
GW
source
Groundwater Concentration at
the Source
mg/L
Equation R13 in
Appendix C, Table C
Calculated Value
H’
Henry’s Law Constant
cm
3
water
/cm
3
air
Appendix C, Table E
Chemical-Specific
i
Hydraulic Gradient
cm/cm (unitless)
Field Measurement
(See Appendix C, Table F)
Site-Specific
I
Infiltration Rate
cm/yr
RBCA
30
IR
air
Daily Outdoor Inhalation Rate
m
3
/d
RBCA
20
IR
soil
Soil Ingestion Rate
mg/d
RBCA
Residential = 100
Industrial/Commercial = 50
Construction Worker = 480
IR
w
Daily Water Ingestion Rate
L/d
RBCA
Residential = 2
Industrial/Commercial = 1
Symbol
Parameter
Units
Source
Parameter Value(s)
K
Aquifer Hydraulic
Conductivity
cm/d for
Equations R15,
R19 and R26
cm/yr for
Equation R24
Field Measurement
(See Appendix C, Table F)
Site-Specific
K
oc
Organic Carbon Partition
Coefficient
cm
3
/g or L/kg
Appendix C, Table E or
Appendix C, Table I
Chemical-Specific
k
s
(non-ionizing
organics)
Soil Water Sorption
Coefficient
cm
3
water
/g
soil
Equation R20 in
Appendix C,Table C
Calculated Value
k
s
(ionizing
organics)
Soil Water Sorption
Coefficient
cm
3
water
/g
soil
Equation R20 in Appendix C, Table
C
Chemical-Specific
k
s
(inorganics)
Soil Water Sorption
Coefficient
cm
3
water
/g
soil
Appendix C,Table J
Chemical-Specific
L
s
Depth to Subsurface Soil
Sources
cm
RBCA
100
LF
sw
Leaching Factor
(mg/L
water
)/
(mg/kg
soil
)
Equation R14 in
Appendix C, Table C
Calculated Value
M
Soil to Skin Adherence Factor
mg/cm
2
RBCA
0.5
Symbol
Parameter
Units
Source
Parameter Value(s)
Pe
Particulate Emission Rate
g/cm
2
-s
RBCA
6.9
•
10
-14
RAF
d
Dermal Relative Absorption
Factor
unitless
RBCA
0.5
RAF
d
(PNAs)
Dermal Relative Absorption
Factor
unitless
RBCA
0.05
RAF
d
(inorganics)
Dermal Relative Absorption
Factor
unitless
RBCA
0
RAF
o
Oral Relative Absorption
Factor
unitless
RBCA
1.0
RBSL
air
Carcinogenic
Risk-Based Screening Level
for Air
ug/m
3
Equation R9 in
Appendix C, Table C
Chemical-, Media-, and Exposure Route-
Specific
RBSL
air
Noncarcinogenic
Risk-Based Screening Level
for Air
ug/m
3
Equations R10 in
Appendix C, Table C
Chemical-, Media-, and Exposure Route-
Specific
RfD
i
Inhalation Reference Dose
mg/kg-d
IEPA (IRIS/HEAST
a
)
Toxicological-Specific
RfD
o
Oral Reference Dose
mg/(kg-d)
IEPA (IRIS/HEAST
a
)
Toxicological-Specific
(Note: for Construction Worker use
subchronic reference doses)
SA
Skin Surface Area
cm
2
/d
RBCA
3,160
Symbol
Parameter
Units
Source
Parameter Value(s)
S
d
Source Width Perpendicular to
Groundwater Flow Direction
in Vertical Plane
cm
Field Measurement
For Migration to Groundwater Route:
Use 200 or Site-Specific
For Groundwater cleanup objective:
Use Site-Specific
S
w
Source Width Perpendicular to
Groundwater Flow Direction
in Horizontal Plane
cm
Field Measurement
Site-Specific
SF
i
Inhalation Cancer Slope Factor
(mg/kg-d)
-1
IEPA (IRIS/HEAST
a
)
Toxicological-Specific
SF
o
Oral Slope Factor
(mg/kg-d)
-1
IEPA (IRIS/HEAST
a
)
Toxicological-Specific
THQ
Target Hazard Quotient
unitless
RBCA
1
TR
Target Cancer Risk
unitless
RBCA
Residential = 10
-6
at the point of human
exposure
Industrial/Commercial = 10
-6
at the point of
human exposure
Construction Worker = 10
-6
at the point of
human exposure
U
Specific Discharge
cm/d
Equation R19 in
Appendix C, Table C
Calculated Value
Symbol
Parameter
Units
Source
Parameter Value(s)
U
air
Average Wind Speed Above
Ground Surface in Ambient
Mixing Zone
cm/s
RBCA
225
U
gw
Groundwater Darcy Velocity
cm/yr
Equation R24 in
Appendix C, Table C
Calculated Value
VF
p
Volatilization Factor for
Surficial Soils Regarding
Particulates
kg/m
3
Equation R5 in
Appendix C, Table C
Calculated Value
VF
samb
Volatilization Factor
(Subsurface Soils to Ambient
Air)
(mg/m
3
air
)/(mg/k
g
soil
) or
kg/m
3
Equation R11 in
Appendix C, Table C
Calculated Value
VF
ss
Volatilization Factor for
Surficial Soils
kg/m
3
Use Equations R3 and R4 in
Appendix C, Table C
Calculated Value from Equation R3 or R4
(whichever is less)
W
Width of Source Area Parallel
to Direction to Wind or
Groundwater Movement
cm
Field Measurement
Site-Specific
Symbol
Parameter
Units
Source
Parameter Value(s)
w
Average Soil Moisture Content
g
water
/g
soil
RBCA or
Field Measurement
(See Appendix C, Table F)
0.1, or
Surface Soil (top 1 meter) = 0.1
Subsurface Soil (below 1 meter) = 0.2, or
Site-Specific
X
Distance along the Centerline
of the Groundwater Plume
Emanating from a Source. The
x direction is the direction of
groundwater flow
cm
Field Measurement
Site-Specific
α
x
Longitudinal Dispersitivity
cm
Equation R16 in
Appendix C, Table C
Calculated Value
α
y
Transverse Dispersitivity
cm
Equation R17 in
Appendix C, Table C
Calculated Value
α
z
Vertical Dispersitivity
cm
Equation R18 in
Appendix C, Table C
Calculated Value
δ
air
Ambient Air Mixing Zone
Height
cm
RBCA
200
Symbol
Parameter
Units
Source
Parameter Value(s)
δ
gw
Groundwater Mixing Zone
Thickness
cm
RBCA
200
θ
as
Volumetric Air Content in
Vadose Zone Soils
cm
3
air
/cm
3
soil
RBCA or
Equation R21 in
Appendix C, Table C
Surface Soil (top 1 meter) = 0.28
Subsurface Soil (below 1 meter)= 0.13,
or
Gravel = 0.05
Sand = 0.14
Silt = 0.16
Clay = 0.17, or
Calculated Value
θ
ws
Volumetric Water Content in
Vadose Zone Soils
cm
3
water
/cm
3
soil
RBCA or
Equation R22 in
Appendix C, Table C
Surface Soil (top 1 meter) = 0.15
Subsurface Soil (below 1 meter) =
0.30,
or
Gravel = 0.20
Sand = 0.18
Silt = 0.16
Clay = 0.17, or
Calculated Value
Symbol
Parameter
Units
Source
Parameter Value(s)
θ
T
Total Soil Porosity
cm
3
/cm
3
soil
RBCA or
Equation R23 in
Appendix C, Table C
0.43, or
Gravel = 0.25
Sand = 0.32
Silt = 0.40
Clay = 0.36, or
Calculated Value
λ
First Order Degradation
Constant
d
-1
Appendix C, Table E
Chemical-Specific
π
pi
3.1416
ρ
s
Soil Bulk Density
g/cm
3
RBCA or
Field Measurement
(See Appendix C, Table F)
1.5, or
Gravel = 2.0
Sand = 1.8
Silt = 1.6
Clay = 1.7, or
Site-Specific
ρ
w
Water Density
g/cm
3
RBCA
1
τ
Averaging Time for Vapor
Flux
s
RBCA
9.46
•
10
8
a
HEAST = Health Effects Assessment Summary Tables. USEPA, Office of Solid Waste and Emergency Response. EPA/540/R-95/036. Updated
Quarterly.
Section 742.APPENDIX C:
Tier 2 Tables and Illustrations
Table E:
Default Physical and Chemical Parameters
CAS No.
Chemical
Solubility in
Water (S)
(mg/L)
Diffusivity in
Air (Di)
(cm
2
/s)
Diffusivity in
Water (D
w
)
(cm
2
/s)
Dimensionless
Henry's Law
Constant (H')
(25
o
C)
Organic
Carbon
Partition
Coefficient
(K
oc
)
(L/kg)
First
Order
Degradation
Constant
(
λ
)
(d
-1
)
Neutral Organics
83-32-9
Acenaphthene
4.24
0.0421
7.69E-6
0.00636
7,080
0.0034
67-64-1
Acetone
1,000,000
0.124
1.14E-5
0.00159
0.575
0.0495
15972-60-8
Alachlor
242
0.0198
5.69E-6
0.00000132
394
No Data
116-06-3
Aldicarb
6,000
0.0305
7.19E-6
0.0000000574
12
0.00109
309-00-2
Aldrin
0.18
0.0132
4.86E-6
0.00697
2,450,000
0.00059
120-12-7
Anthracene
0.0434
0.0324
7.74E-6
0.00267
29,500
0.00075
1912-24-9
Atrazine
70
0.0258
6.69E-6
0.00000005
451
No Data
71-43-2
Benzene
1,750
0.088
9.80E-6
0.228
58.9
0.0009
CAS No.
Chemical
Solubility in
Water (S)
(mg/L)
Diffusivity in
Air (Di)
(cm
2
/s)
Diffusivity in
Water (D
w
)
(cm
2
/s)
Dimensionless
Henry's Law
Constant (H')
(25
o
C)
Organic
Carbon
Partition
Coefficient
(K
oc
)
(L/kg)
First
Order
Degradation
Constant
(
λ
)
(d
-1
)
56-55-3
Benzo(a)anthracene
0.0094
0.0510
9.00E-6
0.000137
398,000
0.00051
205-99-2
Benzo(b)fluoranthene
0.0015
0.0226
5.56E-6
0.00455
1,230,000
0.00057
207-08-9
Benzo(k)fluoranthene
0.0008
0.0226
5.56E-6
0.000034
1,230,000
0.00016
65-85-0
Benzoic Acid
3,500
0.0536
7.97E-6
0.0000631
0.600
No Data
50-32-8
Benzo(a)pyrene
0.00162
0.043
9.00E-6
0.0000463
1,020,000
0.00065
111-44-4
Bis(2-chloroethyl)ether
17,200
0.0692
7.53E-6
0.000738
15.5
0.0019
117-81-7
Bis(2-ethylhexyl)phthalate
0.34
0.0351
3.66E-6
0.00000418
15,100,000
0.0018
75-27-4
Bromodichloromethane
6,740
0.0298
1.06E-5
0.0656
55.0
No Data
75-25-2
Bromoform
3,100
0.0149
1.03E-5
0.0219
87.1
0.0019
71-36-3
Butanol
74,000
0.0800
9.30E-6
0.000361
6.92
0.01283
85-68-7
Butyl Benzyl Phthalate
2.69
0.0174
4.83E-6
0.0000517
57,500
0.00385
86-74-8
Carbazole
7.48
0.0390
7.03E-6
0.000000626
3,390
No Data
CAS No.
Chemical
Solubility in
Water (S)
(mg/L)
Diffusivity in
Air (Di)
(cm
2
/s)
Diffusivity in
Water (D
w
)
(cm
2
/s)
Dimensionless
Henry's Law
Constant (H')
(25
o
C)
Organic
Carbon
Partition
Coefficient
(K
oc
)
(L/kg)
First
Order
Degradation
Constant
(
λ
)
(d
-1
)
1563-66-2
Carbofuran
320
0.0249
6.63E-6
.00377
37
No Data
75-15-0
Carbon Disulfide
1,190
0.104
1.00E-5
1.24
45.7
No Data
56-23-5
Carbon Tetrachloride
793
0.0780
8.80E-6
1.25
174
0.0019
57-74-9
Chlordane
0.056
0.0118
4.37E-6
0.00199
120,000
0.00025
106-47-8
p-Chloroaniline
5,300
0.0483
1.01E-5
0.0000136
66.1
No Data
108-09-7
Chlorobenzene
472
0.0730
8.70E-6
0.152
219
0.0023
124-48-1
Chlorodibromomethane
2,600
0.0196
1.05E-5
0.0321
63.1
0.00385
67-66-3
Chloroform
7,920
0.104
1.00E-5
0.15
39.8
0.00039
95-57-8
2-Chlorophenol
22,000
0.0501
9.46E-6
0.016
388
No Data
218-01-9
Chrysene
0.0016
0.0248
6.21E-6
0.00388
398,000
0.00035
94-75-7
2,4-D
680
0.0231
7.31E-6
0.00000041
451
0.00385
72-54-8
4,4'-DDD
0.09
0.0169
4.76E-6
0.000164
1,000,000
0.000062
CAS No.
Chemical
Solubility in
Water (S)
(mg/L)
Diffusivity in
Air (Di)
(cm
2
/s)
Diffusivity in
Water (D
w
)
(cm
2
/s)
Dimensionless
Henry's Law
Constant (H')
(25
o
C)
Organic
Carbon
Partition
Coefficient
(K
oc
)
(L/kg)
First
Order
Degradation
Constant
(
λ
)
(d
-1
)
72-55-9
4,4'-DDE
0.12
0.0144
5.87E-6
0.000861
4,470,000
0.000062
50-29-3
4,4'-DDT
0.025
0.0137
4.95E-6
0.000332
2,630,000
0.000062
75-99-0
Dalapon
900,000
0.0414
9.46E-6
0.00000264
5.8
0.005775
53-70-3
Dibenzo(a,h)anthracene
0.00249
0.0202
5.18E-6
0.000000603
3,800,000
0.00037
96-12-8
1,2-Dibromo-3-chloropropane
1,200
0.0212
7.02E-6
0.00615
182
0.001925
106-93-4
1,2-Dibromoethane
4,200
0.0287
8.06E-6
0.0303
93
0.005775
84-74-2
Di-n-butyl Phthalate
11.2
0.0438
7.86E-6
0.0000000385
33,900
0.03013
95-50-1
1,2-Dichlorobenzene
156
0.0690
7.90E-6
0.0779
617
0.0019
106-46-7
1,4-Dichlorobenzene
73.8
0.0690
7.90E-6
0.0996
617
0.0019
91-94-1
3,3-Dichlorobenzidine
3.11
0.0194
6.74E-6
0.000000164
724
0.0019
CAS No.
Chemical
Solubility in
Water (S)
(mg/L)
Diffusivity in
Air (Di)
(cm
2
/s)
Diffusivity in
Water (D
w
)
(cm
2
/s)
Dimensionless
Henry's Law
Constant (H')
(25
o
C)
Organic
Carbon
Partition
Coefficient
(K
oc
)
(L/kg)
First
Order
Degradation
Constant
(
λ
)
(d
-1
)
75-34-3
1,1-Dichloroethane
5,060
0.0742
1.05E-5
0.23
31.6
0.0019
107-06-2
1,2-Dichloroethane
8,520
0.104
9.90E-6
0.0401
17.4
0.0019
75-35-4
1,1-Dichloroethylene
2,250
0.0900
1.04E-5
1.07
58.9
0.0053
156-59-2
cis-1,2-Dichloroethylene
3,500
0.0736
1.13E-5
0.167
35.5
0.00024
156-60-5
trans-1,2-Dichloroethylene
6,300
0.0707
1.19E-5
0.385
52.5
0.00024
120-83-2
2,4-Dichlorophenol
4,500
0.0346
8.77E-6
0.00013
147
0.00027
78-87-5
1,2-Dichloropropane
2,800
0.0782
8.73E-6
0.115
43.7
0.00027
542-75-6
1,3-Dichloropropylene
(cis + trans)
2,800
0.0626
1.00E-5
0.726
45.7
0.061
60-57-1
Dieldrin
0.195
0.0125
4.74E-6
0.000619
21,400
0.00032
84-66-2
Diethyl Phthalate
1,080
0.0256
6.35E-6
0.0000185
288
0.00619
105-67-9
2,4-Dimethylphenol
7,870
0.0584
8.69E-6
0.000082
209
0.0495
51-28-5
2,4-Dinitrophenol
2,790
0.0273
9.06E-6
0.0000182
0.01
0.00132
CAS No.
Chemical
Solubility in
Water (S)
(mg/L)
Diffusivity in
Air (Di)
(cm
2
/s)
Diffusivity in
Water (D
w
)
(cm
2
/s)
Dimensionless
Henry's Law
Constant (H')
(25
o
C)
Organic
Carbon
Partition
Coefficient
(K
oc
)
(L/kg)
First
Order
Degradation
Constant
(
λ
)
(d
-1
)
121-14-2
2,4-Dinitrotoluene
270
0.203
7.06E-6
0.0000038
95.5
0.00192
606-20-2
2,6-Dinitrotoluene
182
0.0327
7.26E-6
0.0000306
69.2
0.00192
88-85-7
Dinoseb
52
0.0215
6.62E-6
0.0000189
1,120
0.002817
117-84-0
Di-n-octyl Phthalate
0.02
0.0151
3.58E-6
0.00274
83,200,000
0.0019
115-29-7
Endosulfan
0.51
0.0115
4.55E-6
0.000459
2,140
0.07629
145-73-3
Endothall
21,000
0.0291
8.07E-6
0.0000000107
0.29
No Data
72-20-8
Endrin
0.25
0.0125
4.74E-6
0.000308
12,300
0.00032
100-41-4
Ethylbenzene
169
0.0750
7.80E-6
0.323
363
0.003
206-44-0
Fluoranthene
0.206
0.0302
6.35E-6
0.00066
107,000
0.00019
86-73-7
Fluorene
1.98
0.0363
7.88E-6
0.00261
13,800
0.000691
76-44-8
Heptachlor
0.18
0.0112
5.69E-6
60.7
1,410,000
0.13
1024-57-3
Heptachlor epoxide
0.2
0.0132
4.23E-6
0.00039
83,200
0.00063
CAS No.
Chemical
Solubility in
Water (S)
(mg/L)
Diffusivity in
Air (Di)
(cm
2
/s)
Diffusivity in
Water (D
w
)
(cm
2
/s)
Dimensionless
Henry's Law
Constant (H')
(25
o
C)
Organic
Carbon
Partition
Coefficient
(K
oc
)
(L/kg)
First
Order
Degradation
Constant
(
λ
)
(d
-1
)
118-74-1
Hexachlorobenzene
6.2
0.0542
5.91E-6
0.0541
55,000
0.00017
319-84-6
alpha-HCH (alpha-BHC)
2.0
0.0142
7.34E-6
0.000435
1,230
0.0025
58-89-9
gamma-HCH (Lindane)
6.8
0.0142
7.34E-6
0.000574
1,070
0.0029
77-47-4
Hexachlorocyclo-
pentadiene
1.8
0.0161
7.21E-6
1.11
200,000
0.012
67-72-1
Hexachloroethane
50
0.0025
6.80E-6
0.159
1,780
0.00192
193-39-5
Indeno(1,2,3-c,d)pyrene
0.000022
0.0190
5.66E-6
0.0000656
3,470,000
0.00047
78-59-1
Isophorone
12,000
0.0623
6.76E-6
0.000272
46.8
0.01238
7439-97-6
Mercury
---
0.0307
6.30E-6
0.467
---
No Data
72-43-5
Methoxychlor
0.045
0.0156
4.46E-6
0.000648
97,700
0.0019
74-83-9
Methyl Bromide
15,200
0.0728
1.21E-5
0.256
10.5
0.01824
75-09-2
Methylene Chloride
13,000
0.101
1.17E-5
0.0898
11.7
0.012
95-48-7
2-Methylphenol
26,000
0.0740
8.30E-6
0.0000492
91.2
0.0495
CAS No.
Chemical
Solubility in
Water (S)
(mg/L)
Diffusivity in
Air (Di)
(cm
2
/s)
Diffusivity in
Water (D
w
)
(cm
2
/s)
Dimensionless
Henry's Law
Constant (H')
(25
o
C)
Organic
Carbon
Partition
Coefficient
(K
oc
)
(L/kg)
First
Order
Degradation
Constant
(
λ
)
(d
-1
)
91-20-3
Naphthalene
31.0
0.0590
7.50E-6
0.0198
2,000
0.0027
98-95-3
Nitrobenzene
2,090
0.0760
8.60E-6
0.000984
64.6
0.00176
86-30-6
N-Nitrosodiphenylamine
35.1
0.0312
6.35E-6
0.000205
1,290
0.01
621-64-7
N-Nitrosodi-n-propylamine
9,890
0.0545
8.17E-6
0.0000923
24.0
0.0019
87-86-5
Pentachlorophenol
1,950
0.0560
6.10E-6
0.000001
592
0.00045
108-95-2
Phenol
82,800
0.0820
9.10E-6
0.0000163
28.8
0.099
1918-02-1
Picloram
430
0.0255
5.28E-6
0.00000000166
1.98
No Data
1336-36-3
Polychlorinated biphenyls
(PCBs)
0.7
-------
a
-------
a
-------
a
309,000
No Data
129-00-0
Pyrene
0.135
0.0272
7.24E-6
0.000451
105,000
0.00018
122-34-9
Simazine
5
0.027
7.36E-6
0.0000000133
133
No Data
100-42-5
Styrene
310
0.0710
8.00E-6
0.113
776
0.0033
93-72-1
2,4,5-TP (Silvex)
31
0.0194
5.83E-6
0.0000000032
5,440
No Data
CAS No.
Chemical
Solubility in
Water (S)
(mg/L)
Diffusivity in
Air (Di)
(cm
2
/s)
Diffusivity in
Water (D
w
)
(cm
2
/s)
Dimensionless
Henry's Law
Constant (H')
(25
o
C)
Organic
Carbon
Partition
Coefficient
(K
oc
)
(L/kg)
First
Order
Degradation
Constant
(
λ
)
(d
-1
)
127-18-4
Tetrachloroethylene
200
0.0720
8.20E-6
0.754
155
0.00096
108-88-3
Toluene
526
0.0870
8.60E-6
0.272
182
0.011
8001-35-2
Toxaphene
0.74
0.0116
4.34E-6
0.000246
257,000
No Data
120-82-1
1,2,4-Trichlorobenzene
300
0.0300
8.23E-6
0.0582
1,780
0.0019
71-55-6
1,1,1-Trichloroethane
1,330
0.0780
8.80E-6
0.705
110
0.0013
79-00-5
1,1,2-Trichloroethane
4,420
0.0780
8.80E-6
0.0374
50.1
0.00095
79-01-6
Trichloroethylene
1,100
0.0790
9.10E-6
0.422
166
0.00042
95-95-4
2,4,5-Trichlorophenol
1,200
0.0291
7.03E-6
0.000178
1,600
0.00038
88-06-2
2,4,6-Trichlorophenol
800
0.0318
6.25E-6
0.000319
381
0.00038
108-05-4
Vinyl Acetate
20,000
0.0850
9.20E-6
0.021
5.25
No Data
57-01-4
Vinyl Chloride
2,760
0.106
1.23E-6
1.11
18.6
0.00024
108-38-3
m-Xylene
161
0.070
7.80E-6
0.301
407
0.0019
CAS No.
Chemical
Solubility in
Water (S)
(mg/L)
Diffusivity in
Air (Di)
(cm
2
/s)
Diffusivity in
Water (D
w
)
(cm
2
/s)
Dimensionless
Henry's Law
Constant (H')
(25
o
C)
Organic
Carbon
Partition
Coefficient
(K
oc
)
(L/kg)
First
Order
Degradation
Constant
(
λ
)
(d
-1
)
95-47-6
o-Xylene
178
0.087
1.00E-5
0.213
363
0.0019
106-42-3
p-Xylene
185
0.0769
8.44E-6
0.314
389
0.0019
1330-20-7
Xylenes (total)
186
0.0720
9.34E-6
0.25
260
0.0019
Chemical Abstracts Service (CAS) registry number. This number in the format xxx-xx-x, is unique for each chemical and allows
efficient searching on computerized data bases.
a
Soil Remediation objectives are determined pursuant to 40 CFR 761.120, as incorporated by reference at Section 732.104 (the
USEPA "PCB Spill Cleanup Policy"), for most sites; persons remediating sites should consult with BOL if calculation of Tier 2 soil
remediation objectives is desired.
Section 742.APPENDIX C:
Tier 2 Tables and Illustrations
Table F:
Methods for Determining Physical Soil Parameters
Methods for Determining Physical Soil Parameters
Parameter
Sampling
Location
a
Method
ρ
b
(soil bulk density)
Surface
ASTM - D 1556-90
Sand Cone Method
b
ASTM - D 2167-94
Rubber Balloon
Method
b
ASTM - D 2922-91
Nuclear
Method
b
Subsurface
ASTM - D 2937-94
Drive Cylinder
Method
b
ρ
s
(soil particle density)
Surface or Subsurface
ASTM - D 854-92
Specific Gravity of
Soil
b
w (moisture content)
Surface or Subsurface
ASTM - D 4959-89
(Reapproved 1994)
Standard
b
ASTM - D 4643-93
Microwave
Oven
b
ASTM - D2216-92
Laboratory
Determination
b
ASTM - D3017-88
(Reapproved 1993)
Nuclear
Method
b
Equivalent USEPA Method (e.g.,
sample preparation procedures
described in methods 3541 or 3550)
f
oc
(organic carbon content)
Surface or Subsurface
Nelson and
Sommers (1982)
ASTM - D 2974-87
(Reapproved 1995)
Moisture, Ash, and Organic
Matter
b
USEPA Method 9060A
Total Organic Content
Methods for Determining Physical Soil Parameters
Parameter
Sampling
Location
a
Method
η
or
θ
T
(total soil porosity)
Surface or Subsurface
(calculated)
Equation S24 in Appendix C, Table A
for SSL Model, or Equation R23 in
Appendix C, Table C for RBCA Model
θ
a
or
θ
as
(air-filled soil porosity)
Surface or Subsurface
(calculated)
Equation S21 in Appendix C, Table A
for SSL Model, or Equation R21 in
Appendix C, Table C for RBCA Model
θ
w
or
θ
ws
(water-filled soil porosity)
Surface or Subsurface
(calculated)
Equation S20 in Appendix C, Table A
for SSL Model, or Equation R22 in
Appendix C, Table C for RBCA Model
ASTM - D 5084-90
Flexible Wall
Permeameter
K (hydraulic conductivity)
Surface or Subsurface
Pump Test -
Appendix D
Slug Test -
Appendix D
i (hydraulic gradient)
Surface or Subsurface
Field Measurement
a
This is the location where the sample is collected
b
As incorporated by reference in Section 742.120.
Section 742.APPENDIX C:
Tier 2 Tables and Illustrations
Table G:
Error Function (erf)
(
)
erf
e
d
b
p
e
e
b
=
−
⌠
2
2
0
b
erf
(
β
)
0
0
0.05
0.056372
0.1
0.112463
0.15
0.167996
0.2
0.222703
0.25
0.276326
0.3
0.328627
0.35
0.379382
0.4
0.428392
0.45
0.475482
0.5
0.520500
0.55
0.563323
0.6
0.603856
0.65
0.642029
0.7
0.677801
0.75
0.711156
0.8
0.742101
0.85
0.770668
0.9
0.796908
0.95
0.820891
1.0
0.842701
1.1
0.880205
1.2
0.910314
1.3
0.934008
1.4
0.952285
1.5
0.966105
1.6
0.976348
1.7
0.983790
1.8
0.989091
1.9
0.992790
2.0
0.995322
2.1
0.997021
2.2
0.998137
2.3
0.998857
2.4
0.999311
2.5
0.999593
2.6
0.999764
2.7
0.999866
2.8
0.999925
2.9
0.999959
3.0
0.999978
742.APPENDIX C: Tier 2 Tables and Illustrations
Table H:
Q/C Values by Source Area
Source
(Acres)
Area Q/C Value
(g/m
2
-s per kg/m
3
)
0.5
97.78
1
85.81
2
76.08
5
65.75
10
59.16
30
50.60
Section 742.APPENDIX C:
Tier 2 Tables and Illustrations
TABLE I:
Koc Values for Ionizing Organics as a Function of pH (cm
3
/g or L/kg)
pH
Benzoic Acid
2-Chloro-
phenol
2,4-
Dichloro-
phenol
Pentachloro-
phenol
2,4,5-
Trichloro-
phenol
2,4,6-
Trichloro-
phenol
Dinoseb
2,3,5-TP
(Silvex)
4.5
1.07E+01
3.98E+02
1.59E+02
1.34E+04
2.37E+03
1.06E+03
3.00E+03
1.28E+04
4.6
9.16E+00
3.98E+02
1.59E+02
1.24E+04
2.37E+03
1.05E+03
2.71E+03
1.13E+04
4.7
7.79E+00
3.98E+02
1.59E+02
1.13E+04
2.37E+03
1.05E+03
2.41E+03
1.01E+04
4.8
6.58E+00
3.98E+02
1.59E+02
1.02E+04
2.37E+03
1.05E+03
2.12E+03
9.16E+03
4.9
5.54E+00
3.98E+02
1.59E+02
9.05E+03
2.37E+03
1.04E+03
1.85E+04
8.40E+03
5.0
4.64E+00
3.98E+02
1.59E+02
7.96E+03
2.36E+03
1.03E+03
1.59E+04
7.76E+03
5.1
3.88E+00
3.98E+02
1.59E+02
6.93E+03
2.36E+03
1.02E+03
1.36E+04
7.30E+03
5.2
3.25E+00
3.98E+02
1.59E+02
5.97E+03
2.35E+03
1.01E+03
1.15E+04
6.91E+03
5.3
2.72E+00
3.98E+02
1.59E+02
5.10E+03
2.34E+03
9.99E+02
9.66E+03
6.60E+03
5.4
2.29E+00
3.98E+02
1.58E+02
4.32E+03
2.33E+03
9.82E+02
8.10E+03
6.36E+03
5.5
1.94E+00
3.97E+02
1.58E+02
3.65E+03
2.32E+03
9.62E+02
6.77E+03
6.16E+03
5.6
1.65E+00
3.97E+02
1.58E+02
3.07E+03
2.31E+03
9.38E+02
5.65E+03
6.00E+03
5.7
1.42E+00
3.97E+02
1.58E+02
2.58E+03
2.29E+03
9.10E+02
4.73E+03
5.88E+03
5.8
1.24E+00
3.97E+02
1.58E+02
2.18E+03
2.27E+03
8.77E+02
3.97E+03
5.78E+03
5.9
1.09E+00
3.97E+02
1.57E+02
1.84E+03
2.24E+03
8.39E+02
3.35E+03
5.70E+03
pH
Benzoic Acid
2-Chloro-
phenol
2,4-
Dichloro-
phenol
Pentachloro-
phenol
2,4,5-
Trichloro-
phenol
2,4,6-
Trichloro-
phenol
Dinoseb
2,3,5-TP
(Silvex)
6.0
9.69E-01
3.96E+02
1.57E+02
1.56E+03
2.21E+03
7.96E+02
2.84E+03
5.64E+03
6.1
8.75E-01
3.96E+02
1.57E+02
1.33E+03
2.17E+03
7.48E+02
2.43E+03
5.59E+03
6.2
7.99E-01
3.96E+02
1.56E+02
1.15E+03
2.12E+03
6.97E+02
2.10E+03
5.55E+03
6.3
7.36E-01
3.95E+02
1.55E+02
9.98E+02
2.06E+03
6.44E+02
1.83E+03
5.52E+03
6.4
6.89E-01
3.94E+02
1.54E+02
8.77E+02
1.99E+03
5.89E+02
1.62E+03
5.50E+03
6.5
6.51E-01
3.93E+02
1.53E+02
7.81E+02
1.91E+03
5.33E+02
1.45E+03
5.48E+03
6.6
6.20E-01
3.92E+02
1.52E+02
7.03E+02
1.82E+03
4.80E+02
1.32E+03
5.46E+03
6.7
5.95E-01
3.90E+02
1.50E+02
6.40E+02
1.71E+03
4.29E+02
1.21E+03
5.45E+03
6.8
5.76E-01
3.88E+02
1.47E+02
5.92E+02
1.60E+03
3.81E+02
1.12E+03
5.44E+03
6.9
5.60E-01
3.86E+02
1.45E+02
5.52E+02
1.47E+03
3.38E+02
1.05E+03
5.43E+03
7.0
5.47E-01
3.83E+02
1.41E+02
5.21E+02
1.34E+03
3.00E+02
9.96E+02
5.43E+03
7.1
5.38E-01
3.79E+02
1.38E+02
4.96E+02
1.21E+03
2.67E+02
9.52E+02
5.42E+03
7.2
5.32E-01
3.75E+02
1.33E+02
4.76E+02
1.07E+03
2.39E+02
9.18E+02
5.42E+03
7.3
5.25E-01
3.69E+02
1.28E+02
4.61E+02
9.43E+02
2.15E+02
8.90E+02
5.42E+03
7.4
5.19E-01
3.62E+02
1.21E+02
4.47E+02
8.19E+02
1.95E+02
8.68E+02
5.41E+03
7.5
5.16E-01
3.54E+02
1.14E+02
4.37E+02
7.03E+02
1.78E+02
8.50E+02
5.41E+03
7.6
5.13E-01
3.44E+02
1.07E+02
4.29E+02
5.99E+02
1.64E+02
8.36E+02
5.41E+03
pH
Benzoic Acid
2-Chloro-
phenol
2,4-
Dichloro-
phenol
Pentachloro-
phenol
2,4,5-
Trichloro-
phenol
2,4,6-
Trichloro-
phenol
Dinoseb
2,3,5-TP
(Silvex)
7.7
5.09E-01
3.33E+02
9.84E+01
4.23E+02
5.07E+02
1.53E+02
8.25E+02
5.41E+03
7.8
5.06E-01
3.19E+02
8.97E+01
4.18E+02
4.26E+02
1.44E+02
8.17E+02
5.41E+03
7.9
5.06E-01
3.04E+02
8.07E+01
4.14E+02
3.57E+02
1.37E+02
8.10E+02
5.41E+03
8.0
5.06E-01
2.86E+02
7.17E+01
4.10E+02
2.98E+02
1.31E+02
8.04E+02
5.41E+03
Section 742.APPENDIX C:
Tier 2 Tables and Illustrations
TABLE J:
Values to be Substituted for k
s
when Evaluating Inorganics as a Function of pH (cm
3
water
/g
soil
)
pH
As
Ba
Be
Cd
Cr (+3)
Cr (+6)
Hg
Ni
Ag
Se
Tl
Zn
4.9
2.5E+01
1.1E+01
2.3E+01
1.5E+01
1.2E+03
3.1E+01
4.0E-02
1.6E+01
1.0E-01
1.8E+01
4.4E+01
1.6E+01
5.0
2.5E+01
1.2E+01
2.6E+01
1.7E+01
1.9E+03
3.1E+01
6.0E-02
1.8E+01
1.3E-01
1.7E+01
4.5E+01
1.8E+01
5.1
2.5E+01
1.4E+01
2.8E+01
1.9E+01
3.0E+03
3.0E+01
9.0E-02
2.0E+01
1.6E-01
1.6E+01
4.6E+01
1.9E+01
5.2
2.6E+01
1.5E+01
3.1E+01
2.1E+01
4.9E+03
2.9E+01
1.4E-01
2.2E+01
2.1E-01
1.5E+01
4.7E+01
2.1E+01
5.3
2.6E+01
1.7E+01
3.5E+01
2.3E+01
8.1E+03
2.8E+01
2.0E-01
2.4E+01
2.6E-01
1.4E+01
4.8E+01
2.3E+01
5.4
2.6E+01
1.9E+01
3.8E+01
2.5E+01
1.3E+04
2.7E+01
3.0E-01
2.6E+01
3.3E-01
1.3E+01
5.0E+01
2.5E+01
5.5
2.6E+01
2.1E+01
4.2E+01
2.7E+01
2.1E+04
2.7E+01
4.6E-01
2.8E+01
4.2E-01
1.2E+01
5.1E+01
2.6E+01
5.6
2.6E+01
2.2E+01
4.7E+01
2.9E+01
3.5E+04
2.6E+01
6.9E-01
3.0E+01
5.3E-01
1.1E+01
5.2E+01
2.8E+01
5.7
2.7E+01
2.4E+01
5.3E+01
3.1E+01
5.5E+04
2.5E+01
1.0E-00
3.2E+01
6.7E-01
1.1E+01
5.4E+01
3.0E+01
5.8
2.7E+01
2.6E+01
6.0E+01
3.3E+01
8.7E+04
2.5E+01
1.6E-00
3.4E+01
8.4E-01
9.8E+00
5.5E+01
3.2E+01
5.9
2.7E+01
2.8E+01
6.9E+01
3.5E+01
1.3E+05
2.4E+01
2.3E-00
3.6E+01
1.1E+00
9.2E+00
5.6E+01
3.4E+01
6.0
2.7E+01
3.0E+01
8.2E+01
3.7E+01
2.0E+05
2.3E+01
3.5E-00
3.8E+01
1.3E+00
8.6E+00
5.8E+01
3.6E+01
6.1
2.7E+01
3.1E+01
9.9E+01
4.0E+01
3.0E+05
2.3E+01
5.1E-00
4.0E+01
1.7E+00
8.0E+00
5.9E+01
3.9E+01
6.2
2.8E+01
3.3E+01
1.2E+02
4.2E+01
4.2E+05
2.2E+01
7.5E-00
4.2E+01
2.1E+00
7.5E+00
6.1E+01
4.2E+01
6.3
2.8E+01
3.5E+01
1.6E+02
4.4E+01
5.8E+05
2.2E+01
1.1E+01
4.5E+01
2.7E+00
7.0E+00
6.2E+01
4.4E+01
6.4
2.8E+01
3.6E+01
2.1E+02
4.8E+01
7.7E+05
2.1E+01
1.6E+01
4.7E+01
3.4E+00
6.5E+00
6.4E+01
4.7E+01
6.5
2.8E+01
3.7E+01
2.8E+02
5.2E+01
9.9E+05
2.0E+01
2.2E+01
5.0E+01
4.2E+00
6.1E+00
6.6E+01
5.1E+01
6.6
2.8E+01
3.9E+01
3.9E+02
5.7E+01
1.2E+06
2.0E+01
3.0E+01
5.4E+01
5.3E+00
5.7E+00
6.7E+01
5.4E+01
pH
As
Ba
Be
Cd
Cr (+3)
Cr (+6)
Hg
Ni
Ag
Se
Tl
Zn
6.7
2.9E+01
4.0E+01
5.5E+02
6.4E+01
1.5E+06
1.9E+01
4.0E+01
5.8E+01
6.6E+00
5.3E+00
6.9E+01
5.8E+01
6.8
2.9E+01
4.1E+01
7.9E+02
7.5E+01
1.8E+06
1.9E+01
5.2E+01
6.5E+01
8.3E+00
5.0E+00
7.1E+01
6.2E+01
6.9
2.9E+01
4.2E+01
1.1E+03
9.1E+01
2.1E+06
1.8E+01
6.6E+01
7.4E+01
1.0E+01
4.7E+00
7.3E+01
6.8E+01
7.0
2.9E+01
4.2E+01
1.7E+03
1.1E+02
2.5E+06
1.8E+01
8.2E+01
8.8E+01
1.3E+01
4.3E+00
7.4E+01
7.5E+01
7.1
2.9E+01
4.3E+01
2.5E+03
1.5E+02
2.8E+06
1.7E+01
9.9E+01
1.1E+02
1.6E+01
4.1E+00
7.6E+01
8.3E+01
7.2
3.0E+01
4.4E+01
3.8E+03
2.0E+02
3.1E+06
1.7E+01
1.2E+02
1.4E+02
2.0E+01
3.8E+00
7.8E+01
9.5E+01
7.3
3.0E+01
4.4E+01
5.7E+03
2.8E+02
3.4E+06
1.6E+01
1.3E+02
1.8E+02
2.5E+01
3.5E+00
8.0E+01
1.1E+02
7.4
3.0E+01
4.5E+01
8.6E+03
4.0E+02
3.7E+06
1.6E+01
1.5E+02
2.5E+02
3.1E+01
3.3E+00
8.2E+01
1.3E+02
7.5
3.0E+01
4.6E+01
1.3E+04
5.9E+02
3.9E+06
1.6E+01
1.6E+02
3.5E+02
3.9E+01
3.1E+00
8.5E+01
1.6E+02
7.6
3.1E+01
4.6E+01
2.0E+04
8.7E+02
4.1E+06
1.5E+01
1.7E+02
4.9E+02
4.8E+01
2.9E+00
8.7E+01
1.9E+02
7.7
3.1E+01
4.7E+01
3.0E+04
1.3E+03
4.2E+06
1.5E+01
1.8E+02
7.0E+02
5.9E+01
2.7E+00
8.9E+01
2.4E+02
7.8
3.1E+01
4.9E+01
4.6E+04
1.9E+03
4.3E+06
1.4E+01
1.9E+02
9.9E+02
7.3E+01
2.5E+00
9.1E+01
3.1E+02
7.9
3.1E+01
5.0E+01
6.9E+04
2.9E+03
4.3E+06
1.4E+01
1.9E+02
1.4E+03
8.9E+01
2.4E+00
9.4E+01
4.0E+02
8.0
3.1E+01
5.2E+01
1.0E+05
4.3E+03
4.3E+06
1.4E+01
2.0E+02
1.9E+03
1.1E+02
2.2E+00
9.6E+01
5.3E+02
Section 742.APPENDIX C:
Tier 2 Tables and Illustrations
TABLE K:
Parameter Estimates for Calculating Water-Filled Soil Porosity (
θ
θ
w
)
Soil Texture
a
Saturated Hydraulic
Conductivity, K
s
(m/yr)
1/(2b+3)
b
Sand
1,830
0.090
Loamy Sand
540
0.085
Sandy Loam
230
0.080
Silt Loam
120
0.074
Loam
60
0.073
Sandy Clay Loam
40
0.058
Silt Clay Loam
13
0.054
Clay Loam
20
0.050
Sandy Clay
10
0.042
Silt Clay
8
0.042
Clay
5
0.039
a
The appropriate texture classification is determined by a particle size analysis by ASTM
D2488-93 as incorporated by reference in Section 742.210 and the U.S. Department of
Agriculture Soil Textural Triangle shown in Appendix C, Illustration C.
b
Where b is the soil-specific exponential parameter (
unitless)
Section 742.APPENDIX C:
Tier 2 Tables and Illustrations
Illustration A: Tier 2 Evaluation for Soil
Determine the
contaminants that exceed
Tier 1 objectives
Select equations and site
specific information to be
utilized.
Determine
objectives for
Inhalation
Determine
objectives for
Migration to
Groundwater
Determine
objectives for
Ingestion
If the industrial/commercial
assumptions are used, the
calculations must be run for
construction workers also.
Is the lowest objective
developed from the
three routes achieved?
No Further Remediation
(Institution controls may be required)
Remediate to the
objective developed
Go to Tier 3
No
Yes
No
No Further Remediation
(Institutional controls may be required)
Section 742.APPENDIX C:
Tier 2 Tables and Illustrations
Illustration B: Tier 2 Evaluation for Groundwater
Identify contaminants of concern which
exceed the Tier 1 groundwater
remediation objectives
Determine the horizontal and vertical
extent of the area the Tier 2 objective
is to be applied
Take action to remove any free product
Demonstrate all of the following:
contaminant
level will not
exceed the
Tier 1 level or
health
advisory at the
point of
human
exposure
contaminant
level will not
exceed Tier
1 levels
within a
setback
zone
contaminant
level will not
exceed surface
water quality
standards at any
discharge point
the source of
the release is
not within a
setback zone
or regulated
recharge area
institutional
controls are
in place if
engineered
barriers are to
be used
Develop a Tier 2 groundwater
remediation objective
(cannot not exceed the water
solubility of the contaminant)
Are the Tier 2
remediation objectives
achieved?
No Further Remediation
Yes
No
Conduct remediation
or a Tier 3 evaluation
Section 742.APPENDIX C:
Tier 2 Tables and Illustrations
Illustration C: U.S. Department of Agriculture Soil Texture Classification
10
20
30
40
50
60
70
80
90
100
10
20
30
40
50
60
70
80
90
100
10
20
30
40
50
60
70
80
90
100
Clay
Sandy
Clay
Sandy Clay Loam
Clay Loam
Silty
Clay
Silty Clay
Loam
Sandy Loam
Sand
Silt Loam
Silt
Loam
Loamy
Sand
Percent Clay
Percent Silt
Percent Sand
Criteria Used with the Field Method for Determining Soil Texture Classes
Criterion
1.
Individual grains
visible to eye
2. Stability of dry
clods
3. Stability of wet
clods
4. Stability of
"ribbon" when
wet soil rubbed
between thumb
and fingers
Sand
Yes
Do not form
Unstable
Does not
form
Sandy loam
Yes
Do not form
Slightyl stable
Does not form
Loam
Some
Easily
broken
Moderately
stable
Does not form
Slit loam
Few
Moderately
easily broken
Stable
Broken
appearance
Clay loam
No
Hard and
stable
Very stable
Thin, will
break
Clay
No
Very hard
and stable
Very stable
Very long,
flexible
Particle Size, mm
0.002
Clay
Silt
0.05
Very Fine
Fine
Med.
Coarse
Very Coarse
Gravel
Sand
0.10
0.25
0.5
1.0
2.0
249
Section 742.APPENDIX D: Procedures for Determination of Class II Groundwater
The following is a procedure to demonstrate that groundwater beneath a site does not meet the
Class I criteria set forth in 35 Ill. Adm. Code 620.210 and therefore, need only meet the Class
II groundwater quality standards. Groundwater is classified in 35 Ill. Adm. Code 620 as a
Class II, general resource groundwater when it:
1) Does not meet the provisions of 35 Ill. Adm. Code 620.230 (Class III) or 35
Ill. Adm. Code 620.240 (Class IV); (Determining whether the groundwater is
Class III or Class IV is relatively straight forward, as is the requirement to
determine if the groundwater has previously been classified as Class II
groundwater by the Illinois Pollution Control Board (Board).) or,
2) Has been found by the Board to be a Class II groundwater, pursuant to the
petition procedures set forth in 35 Ill. Adm. Code 620.260; (if a continuous
zone containing groundwater begins within 10 feet of the ground surface and
extends greater than ten feet below the ground surface it will not be considered
a Class II groundwater if an additional criterion is met under 35 Ill. Adm. Code
620.210, in this case it would be considered Class I groundwater. Although it
may be possible, it is unrealistic to try to designate two distinct classes of
groundwater within the same saturated hydrogeologic unit. But, if the person
conducting the remediation can demonstrate that by cleaning the groundwater
within ten feet of the surface to Class II specifications will not degrade the
groundwater greater than 10 feet below the ground surface above Class I
standards, the Agency may approve both Class I and II standards in accordance
with the location of the groundwater.) or,
3) Is located less than ten feet below the ground surface; or,
4) Does not meet the provisions of 35 Ill. Adm. Code 620.210, which is further
discussed in paragraphs (A) through (D) below.
Initially, the sources of information listed below should be considered to determine the
appropriate classification of groundwater:
1) Published data concerning regional and local geologic and hydrogeologic
conditions (i.e. geologic surveys, former site investigations, etc.).
2) The locations of all potable water wells located within one mile of the site with
the logs and/or dates of well completion attached.
3) Available data on-site boring logs which characterize the geology from ground
surface to the first saturated unit or, if a perched zone is present, the first
saturated unit below the perched zone.
250
If after collecting and reviewing the above information the groundwater is clearly not a Class
II groundwater and one still wishes to pursue classification as Class II groundwater, further
investigation including site-specific information must be utilized to make a determination that
the groundwater is subject to the Class II standards. If the site geology or hydrogeologic
properties pass all criteria listed below, the groundwater is a Class II groundwater. The
information requirements listed describe the minimum documentation which should be
provided to the Agency.
A) Groundwater cannot be located within the minimum setback of a well which serves as a
potable water supply and to the bottom of such well;
The minimum setback zone of a well extends from the land surface to the bottom of the
well as determined by the screen depth. This establishes a three-dimensional zone of
protection around the well.
Section 14 of the Environmental Protection Act (Act) established setback requirements
for potable water supply wells and potential sources/routes of contamination. Unless
regulatory relief consistent with this Section of the Act has been sought and received,
no new sources/routes may be located within 200 feet of a potable water supply well or
400 feet of a vulnerable community water supply well. Further, the converse of this
statement also applies (e.g., no new potable water supply well may locate within 200
feet of a current or future source/route). A 400 foot separation is required for a
vulnerable community water supply well. In addition, a community water supply may
establish maximum setback zones of up to 1,000 feet around the wells. This may cause
further siting restrictions for new activities as well as require technology controls under
35 Ill. Adm. Code 615/616 for existing and new activities.
This requirement may be satisfied by the submission of a scaled map delineating the
site and all potable water wells located within a one mile radius from the unit(s) of
concern. The Illinois State Water Survey and/or the Division of Public Water Supplies
of the Agency should be contacted, as well as other appropriate state and federal
entities, to obtain this information. A copy of the state or federal agency’s response to
an information inquiry should be included with the information submitted by the person
conducting the remediation. Also, a visual inspection of the area within 200 feet of the
unit(s) of concern should be conducted when possible to detect unplugged private wells.
B) Formations beneath the site cannot consist of unconsolidated sand, gravel, or sand and
gravel which is 5 feet or more in thickness and that contains 12 percent or less in fines
(i.e. fines which pass through a No. 200 sieve tested according to ASTM Standard
Practice D2488-93);
This criterion is specific to the type of formations listed. If a zone of saturation fails
this Class II criterion, Class II may still apply pursuant to D below.
251
This criterion may be satisfied by the submission of, at a minimum, one site-specific,
continuously sampled boring log which clearly identifies the saturated interval from
which a representative sample was obtained. Sieve test analysis should be conducted
on several samples from each saturated interval which is at least five feet in thickness
and composed of sand-sized grains or greater. In addition, the person conducting the
remediation should submit the sieve data sheet, plot, and a scaled map which identifies
the location of each boring.
C) Formations beneath the site cannot consist of sandstone which is 10 feet or more in
thickness, or fractured carbonate which is 15 feet or more in thickness; or
This requirement may be satisfied by the submission of, at a minimum, one site-
specific, continuously sampled boring log with a description of the geologic material
present. This boring log should extend from the ground surface to a depth which is 10
feet into the uppermost water-bearing unit subject to Class I standards or bedrock,
whichever is shallower. The boring(s) should be continuously sampled and located on
a scaled site map. A representative sample, as used previously, is a sample obtained
from each distinctive saturated unit within the boring. Also, a literature search of
regional and local geologic conditions should be conducted with the results submitted to
the Agency.
D) Class II shall not include any geologic material which is shown capable of either of the
following:
•
Sustained groundwater yield, from up to a 12 inch borehole, of 150 gallons per
day or more from a thickness of 15 feet or less; or
This requirement may be satisfied by the submission of continuously sampled
boring logs which demonstrate aquifer thickness. In addition, as-built well
construction diagrams should also be submitted to the Agency for review.
Furthermore, a pump test or equivalent must be conducted to determine the
yield of the geologic material. Methodology, assumptions, and any calculations
performed should also be submitted to meet this requirement. If the aquifer
geometry and transmissivity have been obtained through a site-specific field
investigation, an analytical solution may be used to estimate well yield. The
person conducting the remediation must demonstrate the appropriateness of an
analytical solution to estimate well yield versus an actual field test. Well yield
should be determined for either confined or unconfined conditions.
The pump test should consider some minimum pumping rate during the test; the
following criteria should be used:
i) If all areas within 200 feet of the site have access to a water main to
provide drinking water from a public water supply system, then a
252
minimum pumping rate of 4 gallons per minute should be used when
performing this test.
ii) If all areas within 200 feet of the site do not have access to a water main
to provide drinking water from a public water supply system, then a
minimum pumping rate of 0.5 gallons per minute should be used when
performing this test.
•
Hydraulic conductivity of 1 x 10
-4
cm/sec or greater using one of the following
test methods or its equivalent:
This requirement may be satisfied by performing field and/or lab tests such as a
permeameter, slug test, and/or pump test.
An appropriate method of evaluation should be chosen based on the type of
wells, the length of time over which data may need to be collected and, if
known, the characteristics of the targeted aquifer. Such methods and the
suggested information to be submitted to the Agency are outlined below and
shall include at least one of the following:
i) Permeameter
If this method is chosen, samples of unconsolidated materials should be
left in the field-sampling tubes which then become the permeameter
sample chamber. Proceeding in this manner should allow as little
disruption to the sample as possible. Unconsolidated samples should not
be repacked into the sample chamber. An outline of the laboratory test
method used and a description of the steps followed (including any
calculations) should be submitted to the Agency for review.
ii) Slug tests
This information to be submitted to the Agency should include a
description of the slug test method utilized and a discussion of the
procedures followed during the tests, including any calculations
performed.
A significant drawback to performing a slug test is that it is heavily
dependent on a high-quality intake. If a well point is clogged or
corroded, measured values may be inaccurate. Also, if a well is
developed by surging or backwashing prior to testing, the measured
values may reflect increased conductivities in the artificially included
gravel pack around the intake. If slug tests are chosen, a sufficient
number of tests should be run to ensure that representative measures of
253
hydraulic conductivities have been obtained and that lateral variations at
various depths are documented.
iii) Pump tests
Preliminary or short-term drawdown tests should be performed initially
to assess the appropriate pumping rate for the constant-rate tests.
Several methods and/or equations may be used in evaluating data
generated from pump tests such as Theis, Hantush-0Jacob, Hvorslev
and/or Theim equations. The method(s) of evaluation selected should be
provided to the Agency with justification for their use, (explanations of
any assumptions made and examples of all calculations performed along
with a description of the physical tests performed including the type of
pump used.)
NOTE: It may be beneficial to use laboratory evaluation methods to further
support results of field tests; however, field methods provide the best definition
of the hydraulic conductivity in most cases. The most appropriate method to
determine hydraulic conductivity for most sites will be the pump test, provided
proper evaluation of the data obtained from the test is utilized. Pump tests
provide in-situ measurements that are averaged over a large aquifer volume and
are preferred since they are able to characterize a greater portion of the
subsurface compared to the other aquifer tests. Slug tests provide in-situ values
representative of a small volume of porous media in the immediate vicinity of a
piezometer tip, providing point values only, and may be more appropriate in
very low-permeability materials in which conductivity is too small to conduct a
pump test.
IT IS SO ORDERED.
I, Dorothy M. Gunn, Clerk of the Illinois Pollution Control Board, hereby certify that
the above opinion and order was adopted on the ________ day of ___________, 1997, by a
vote of _______.
__________________________
Dorothy M. Gunn, Clerk
Illinois Pollution Control Board