ILLINOIS POLLUTION CONTROL BOARD

SUBPART A: GENERAL WATER QUALITY PROVISIONS

Section 302.102
Allowed Mixing, Mixing Zones and ZIDs

a)	Whenever a water quality standard is more restrictive than its corresponding effluent standard, or where there is no corresponding effluent standard specified at 35 Ill. Adm. Code 304, an opportunity shall be allowed for compliance with 35 Ill. Adm. Code 304.105 by mixture of an effluent with its receiving waters, provided the discharger has made every effort to comply with the requirements of 35 Ill. Adm. Code 304.102.

b)	The portion, volume and area of any receiving waters within which mixing is allowed pursuant to subsection (a) shall be limited by the following:

1)	Mixing must be confined in an area or volume of the receiving water no larger than the area or volume which would result after incorporation of outfall design measures to attain optimal mixing efficiency of effluent and receiving waters. Such measures may include, but are not limited to, use of diffusers and engineered location and configuration of discharge points.

2)	Mixing is not allowed in waters which include a tributary stream entrance if such mixing occludes the tributary mouth or otherwise restricts the movement of aquatic life into or out of the tributary.

3)	Mixing is not allowed in water adjacent to bathing beaches, bank fishing areas, boat ramps or dockages or any other public access area.

4)	Mixing is not allowed in waters containing mussel beds, endangered species habitat, fish spawning areas, areas of important aquatic life habitat, or any other natural features vital to the well being of aquatic life in such a manner that the maintenance of aquatic life in the body of water as a whole would be adversely affected.

5)	Mixing is not allowed in waters which contain intake structures of public or food processing water supplies, points of withdrawal of water for irrigation, or watering areas accessed by wild or domestic animals.

6)	Mixing must allow for a zone of passage for aquatic life in which water quality standards are met. However, a zone of passage is not required in receiving streams that have zero flow for at least seven consecutive days recurring on average in nine years out of ten.

7)	The area and volume in which mixing occurs, alone or in combination with other areas and volumes of mixing, must not intersect any area of any body of water in such a manner that the maintenance of aquatic life in the body of water as a whole would be adversely affected.

8)	The area and volume in which mixing occurs, alone or in combination with other areas and volumes of mixing must not contain more than 25% of the cross-sectional area or volume of flow of a stream except for those streams where the dilution ratio is less than 3:1. In streams where the dilution ratio is less than 3:1, the volume in which mixing occurs, alone or in combination with other volumes of mixing, must not contain more than 50 % of the volume flow unless an applicant for an NPDES permit demonstrates, pursuant subsection (d) of this section, that an adequate zone of passage is provided for pursuant to Section 302.102(b)(6). ~~Mixing is not allowed in receiving waters which have a zero minimum seven day low flow which occurs once in ten years~~.

9)	No mixing is allowed where the water quality standard for the constituent in question is already violated in the receiving water.

10)	No body of water may be used totally for mixing of single outfall or combination of outfalls, except as provided in Section 302.102(b)(6).

11)	Single sources of effluents which have more than one outfall shall be limited to a total area and volume of mixing no larger than that allowable if a single outfall were used.

12)	The area and volume in which mixing occurs must be as small as is practicable under the limitations prescribed in this subsection, and in no circumstances may the mixing encompass a surface area larger than 26 acres.

c)	All water quality standards of this Part must be met at every point outside of the area and volume of the receiving water within which mixing is allowed. The acute toxicity standards of Sections 302.208 and 302.210 must be met within the area and volume within which mixing is allowed, except as provided in subsection (e).

d)	Pursuant to the procedures of Section 39 of the Act and 35 Ill. Adm. Code 309, a person may apply to the Agency to include as a condition in an NPDES permit formal definition of the area and volume of the waters of the State within which mixing is allowed for the NPDES discharge in question. Such formally defined area and volume of allowed mixing shall constitute a "mixing zone" for the purposes of 35 Ill. Adm. Code: Subtitle C. Upon proof by the applicant that a proposed mixing zone conforms with the requirements of Section 39 of the Act, this Section and any additional limitations as may be imposed by the Clean Water Act (CWA) (33 USC ~~U.S.C~~ 1251 et seq.), the Act or Board regulations, the Agency shall, pursuant to Section 39(b) of the Act, include within the NPDES permit a condition defining the mixing zone.

e)	Pursuant to the procedures of Section 39 of the Act and 35 Ill. Adm. Code 309, a person may apply to the Agency to include as a condition in an NPDES permit a ZID as a component portion of a mixing zone. Such ZID shall, at a minimum, be limited to waters within which effluent dispersion is immediate and rapid. For the purposes of this subsection, "immediate" dispersion means an effluent's merging with receiving waters without delay in time after its discharge and within close proximity of the end of the discharge pipe, so as to minimize the length of exposure time of aquatic life to undiluted effluent, and "rapid" dispersion means an effluent's merging with receiving waters so as to minimize the length of exposure time of aquatic life to undiluted effluent. Upon proof by the applicant that a proposed ZID conforms with the requirements of Section 39 of the Act and this Section, the Agency shall, pursuant to Section 39(b) of the Act, include within the NPDES permit a condition defining the ZID.

f)	Pursuant to Section 39 of the Act and 35 Ill. Adm. Code 309.103, an applicant for an NPDES permit shall submit data to allow the Agency to determine that the nature of any mixing zone or mixing zone in combination with a ZID conforms with the requirements of Section 39 of the Act and of this Section. A permittee may appeal Agency determinations concerning a mixing zone or ZID pursuant to the procedures of Section 40 of the Act and 35 Ill. Adm. Code 309.181.

g)	Where a mixing zone is defined in an NPDES permit, the waters within that mixing zone, for the duration of that NPDES permit, shall constitute the sole waters within which mixing is allowed for the permitted discharge. It shall not be a defense in any action brought pursuant to 35 Ill. Adm. Code 304.105 that the area and volume of waters within which mixing may be allowed pursuant to subsection (b) is less restrictive than the area or volume or waters encompassed in the mixing zone.

h)	Where a mixing zone is explicitly denied in a NPDES permit, no waters may be used for mixing by the discharge to which the NPDES permit applies, all other provisions of this Section notwithstanding.

i)	Where an NPDES permit is silent on the matter of a mixing zone, or where no NPDES permit is in effect, the burden of proof shall be on the discharger to demonstrate compliance with this Section in any action brought pursuant to 35 Ill. Adm. Code 304.105.

OPINION AND ORDER OF THE BOARD (by G.T. Girard):

	The Illinois Environmental Protection Agency (IEPA) proposed rules to update existing general use water quality standards for sulfate and total dissolved solids (TDS) by amending or repealing certain sections and parts of 35 Ill. Adm. Code Parts 302, 309, 405, 406, and 407 of the Board’s water and mine-related pollution rules. On September 20, 2007, the Board proposed, for first notice, the rule as proposed by IEPA with certain specific changes. Those changes included the addition of language reflecting current IEPA practice to the rules on mixing zones and the amendment of mixing zone regulations to allow mixing in certain small streams when adequate dilution is not available.

	On June 19, 2008, the Board proposed for second notice the rule, amending the language from first notice. Specifically, the Board amended the rule by clarifying: 1) how the sulfate standard for waters where chloride concentrations are above 500 milligrams per liter (mg/L) and hardness is 500 mg/L or lower would be set and, 2) how much of the steam volume may be used for mixing when the dilution ration is less than 3:1.

	Today the Board proceeds to final notice making only slight changes as suggested by the Joint Committee on Administrative Rules (JCAR). JCAR voted to issue a certificate of no objection on August 19, 2008.

	The Board will briefly describe the procedural background and then summarize the rule. Next, the Board will discuss the reasons for proceeding to final notice.

PROCEDURAL BACKGROUND

	On May 1, 2008, the Board adopted a proposed second notice to allow for comment on changes to the first notice proposal proposed at second notice. The Board allowed comments to be filed until June 2, 2008. On June 2, 2008, the Environmental Groups filed a comment (PC 13).

	On June 19, 2008, the Board adopted the rule for second notice and filed the rule with JCAR. On August 19, 2008, JCAR voted a certificate of no objection to the rule.

SUMMARY OF THE RULE

	IEPA’s proposed rule set forth a sulfate standard for general use waters that varied from 500 milligrams per liter (mg/L) to 2,500 mg/L, depending on the associated chloride and hardness levels measured in the water. The sulfate standard in waters used for livestock watering had a maximum level of 2,000 mg/L. The proposal eliminated the total dissolved solids (TDS) water quality standard for general use waters. The proposal also amended the mixing zone regulations to allow for mixing in 7Q1.1 zero flow streams ² , and in streams with less than a 3:1 dilution ratio. Finally, the proposal deleted the provisions addressing separate sulfate and chloride water quality standards for discharges from mining operations. Discharges from mining operations would be subject to the general use water quality standards under the proposed regulations. The Board requested additional comment on several of the provisions proposed for first notice, particularly regarding the economic reasonableness of the proposal to delete a special sulfate water quality standard for coal mines.

	In response to the comments, the Board made changes to Section 302.208(h)(3)(C) and Section 309.102(b)(8). Specifically, the Board amended Section 302.208(h)(3)(C) to establish a standard for sulfate where chlorides exceed 500 mg/L and hardness is at or below 500 mg/L, according to Section 303(c) of the Clean Water Act and federal regulations at 40 C.F.R. 131.10(j)(2). Section 309.102(b)(8) was amended to require an NPDES permit applicant seeking a mixing zone more than 50% of the volume flow in streams where the dilution ratio is less than 3:1 to demonstrate the provision of an adequate zone of passage.

DISCUSSION

	Section 27 of the Act obligates IEPA to provide an economic analysis to the Board and requires the Board to determine that the rule is economically reasonable and technically feasible. 415 ILCS 5/27 (2006). Specifically, the Act requires a person filing a proposed rule with the Board to “describe, to the extent reasonably practicable, the universe of affected sources and facilities and the economic impact of the proposed rule.” 415 ILCS 5/27(a) (2006). The Board finds that IEPA has described affected sources including “19 active coal mines in Illinois at the present time.” PC 2 at 2. Further, IEPA has described the economic reasonableness of the proposed sulfate standards. Specifically, IEPA analyzed point sources (including mining operations) within three categories (PC 11 at 3) concluding that only a small number of existing mines would need to employ additional controls such as best management practices.

	The Illinois Coal Association (ICA) submitted as Hearing Exhibit 2 a technical report, dated May 1, 2004 through April 30, 2005, on the economic impact for coal mines. No other group has provided specific cost estimates. ICA’s report estimated that the total annualized cost (capital and operating) for all coal mines in Illinois for compliance with a 2000 mg/L sulfate standard would be $730 million over a ten-year period. Exhibit 2 at 11. For compliance with a 500 mg/L standard, the report estimated a total annualized cost of $7.5 billion over a ten-year period. Id.

	The Board carefully reviewed ICA’s report and the rest of the record, and found that the record supported proceeding to first notice with the proposed sulfate standard as amended by the Board. The Board concluded that ICA’s economic analysis was based on an assumption that additional treatment would be required for coal mines to achieve compliance, but that the Board’s proposed changes to mixing provisions would allow mixing as a means of compliance, thus significantly reducing the proposed rules’ economic impact upon industrial dischargers and coal mines. See Triennial Review of Sulfate and Total Dissolved Solids Water Quality Standards: Proposed Amendments to 35 Ill. Adm. Code 302.102(b)(6), 302.102(b)(8), 302.102(b)(10), 302.208(g), 309.103(c)(3), 405.109(b)(2)(A), 405.109(b)(2)(B), 406.100(d); Repealer of 35 Ill. Adm. Code 406.203 and Part 407; and Proposed New 35 Ill. Adm. Code 302.206(h) (Triennial Review), R07-9, slip op. at 30-31 (Sept. 20, 2007) (first notice).

	The Board notes that, in accordance with Section 27(b) of the Act (415 ILCS 5/27(b) (2006)), the Board conducted a public hearing on the economic impact of the proposed rules and notified the public at least 20 days before the hearing. 415 ILCS 5/27(b)(2) (2008). The Board requested that the Department of Commerce and Economic Opportunity conduct a study of the economic impact of the proposed rules. Id. at (b)(1).

	No additional hearings were requested, and no participant besides the ICA has submitted any additional economic data regarding the economic reasonableness of the proposed sulfate standard. The Board again carefully reviewed the record and considered all evidence in the record regarding the economic reasonableness of the proposed rules including sulfate standards on mining operations, before proceeding to second notice. The Board found that the record supports proceeding to second notice with the rule including the sulfate standards as proposed by IEPA. Triennial Review of Sulfate and Total Dissolved Solids Water Quality Standards: Proposed Amendments to 35 Ill. Adm. Code 302.102(b)(6), 302.102(b)(8), 302.102(b)(10), 302.208(g), 309.103(c)(3), 405.109(b)(2)(A), 405.109(b)(2)(B), 406.100(d); Repealer of 35 Ill. Adm. Code 406.203 and Part 407; and Proposed New 35 Ill. Adm. Code 302.206(h) (Triennial Review), R07-9, slip op. at 30-31 (June 19, 2008) (second notice).

	During the proposed second notice period, only one comment was received (PC 13) and the Board amended the rulemaking language to address those concerns before proceeding to second notice.

	The Board therefore finds that the rule is technically feasible and economically reasonable. Further, the Board finds that the record supports proceeding to adoption with the rule as proposed at second notice making only the changes suggested by JCAR.

CONCLUSION

	The Board finds that the record supports proceeding to final notice with IEPA’s proposal as amended by the Board. The Board finds the record establishes that the rulemaking is technically feasible and economically reasonable. Therefore the Board will proceed with final adoption of this rule.

ORDER

	The Board adopts the proposed amendments set forth below for final notice and directs the Clerk to cause the rules to be filed with the Secretary of State for publication in the Illinois Register for final adoption.

302.553	Determining the Lake Michigan Aquatic Toxicity Criteria or Values - General Procedures
302.555	Determining the Tier I Lake Michigan Acute Aquatic Toxicity Criterion (LMAATC): Independent of Water Chemistry
302.560	Determining the Tier I Lake Michigan Basin Acute Aquatic Life Toxicity Criterion (LMAATC): Dependent on Water Chemistry
302.563	Determining the Tier II Lake Michigan Basin Acute Aquatic Life Toxicity Value (LMAATV)
302.565	Determining the Lake Michigan Basin Chronic Aquatic Life Toxicity Criterion (LMCATC) or the Lake Michigan Basin Chronic Aquatic Life Toxicity Value (LMCATV)

302.575	Procedures for Deriving Tier I Water Quality Criteria and Values in the Lake Michigan Basin to Protect Wildlife
302.580	Procedures for Deriving Water Quality Criteria and Values in the Lake Michigan Basin to Protect Human Health – General
302.585	Procedures for Determining the Lake Michigan Basin Human Health Threshold Criterion (LMHHTC) and the Lake Michigan Basin Human Health Threshold Value (LMHHTV)
302.590	Procedures for Determining the Lake Michigan Basin Human Health Nonthreshold Criterion (LMHHNC) or the Lake Michigan Basin Human Health Nonthreshold Value (LMHHNV)

	On November 27, 2006, in accordance with Section 27(b) of the Act (415 ILCS 5/27(b) (2006)), the Board requested that the Department of Commerce and Economic Opportunity (DCEO) conduct an economic impact study for this rulemaking. To date, the Board has not received a response from DCEO.

Environmental Groups (PC 8).

	On September 20, 2007, the Board adopted the rule for first notice. The proposed rule was published in the Illinois Register on October 5, 2007 (31 Ill. Reg. 13624 (Oct. 5, 2007)). On October 11, 2007, by hearing officer order, the Board extended the deadline for filing first-notice public comments to December 3, 2007. The Board has received the following public comments since the rule was adopted for first notice:

302.612	Determining the Acute Aquatic Toxicity Criterion for an Individual Substance – General Procedures
302.615	Determining the Acute Aquatic Toxicity Criterion - Toxicity Independent of Water Chemistry
302.618	Determining the Acute Aquatic Toxicity Criterion - Toxicity Dependent on Water Chemistry
302.621	Determining the Acute Aquatic Toxicity Criterion - Procedure for Combinations of Substances
302.627	Determining the Chronic Aquatic Toxicity Criterion for an Individual Substance - General Procedures
302.630	Determining the Chronic Aquatic Toxicity Criterion - Procedure for Combinations of Substances

302.APPENDIX C
Maximum total ammonia nitrogen concentrations allowable for certain combinations of pH and temperature

302.APPENDIX D
Section 302.206(d): Stream Segments for Enhanced Dissolved Oxygen Protection

a)
The acute standard (AS) for the chemical constituents listed in subsection (e) shall not be exceeded at any time except as provided in subsection (d).

c)
The human health standard (HHS) for the chemical constituents listed in subsection (f) shall not be exceeded when the stream flow is at or above the harmonic mean flow pursuant to Section 302.658 nor shall an annual average, based on at least eight samples, collected in a manner representative of the sampling period, exceed the HHS except as provided in subsection (d).

d)
In waters where mixing is allowed pursuant to Section 302.102, the following apply:

1)
The AS shall not be exceeded in any waters except for those waters for which the Agency has approved a zone of initial dilutions (ZID) pursuant to Section 302.102.

2)
The CS shall not be exceeded outside of waters in which mixing is allowed pursuant to Section 302.102.

3)
The HHS shall not be exceeded outside of waters in which mixing is allowed pursuant to Section 302.102.

e)	Numeric Water Quality Standards for the Protection of Aquatic Organisms

Constituent	STORET Number	AS (µg/L)	CS (µg/L)
Arsenic (trivalent, dissolved)	22680
Cadmium (dissolved)	01025	~~exp~~ where and	~~exp~~ where and
Chromium (hexavalent, total)	01032	16	11
Chromium (trivalent, dissolved)	80357	~~exp~~ , where and	~~exp~~ , where and
Copper (dissolved)	01040	~~exp~~ , where and	~~exp~~ , where and
Cyanide	00718	22	5.2
Lead (dissolved)	01049	~~exp~~ where and	~~exp~~ where and
Mercury (dissolved)	71890
Nickel (dissolved)	01065	~~exp~~ , where and	~~exp~~ , where and
TRC	500600	19	11
Zinc (dissolved)	01090	~~exp~~ , where and	~~exp~~ , where and
Benzene	78124	4200	860
Ethyl-benzene	78113	150	14
Toluene	78131	2000	600
Xylene(s)	81551	920	360

where:	µg/L	= microgram per liter,
	~~exp^[x]~~	= base of natural logarithms raised to the x- power,
		= natural logarithm of Hardness (STORET 00900)~~, and~~
	*	= conversion factor multiplier for dissolved metals

	where:		µg/L	= micrograms per liter

f)
Numeric Water Quality Standard for the Protection of Human Health

Constituent	STORET Number	(µg/L)
Mercury	71900	0.012
Benzene	78124	310

g)
Concentrations of the following chemical constituents shall not be exceeded except in waters for which mixing is allowed pursuant to Section 302.102.

Constituent	Unit	STORET Number	Standard
Barium (total)	mg/L	01007	5.0
Boron (total)	mg/L	01022	1.0
Chloride (total)	mg/L	00940	500
Fluoride	mg/L	00951	1.4
Iron (dissolved)	mg/L	01046	1.0
Manganese (total)	mg/L	01055	1.0
Phenols	mg/L	32730	0.1
Selenium (total)	mg/L	01147	1.0
Silver (total)	µg/L	01077	5.0
~~Sulfate~~	~~mg/L~~	~~00945~~	~~500~~
~~Total Dissolved~~ ~~Solids~~	~~mg/L~~	~~70300~~	~~1000~~


where:		mg/L	= milligram per liter and
	µg/L	= microgram per liter

h)	The following concentrations for sulfate must not be exceeded except in receiving waters for which mixing is allowed pursuant to Section 302.102:

1)	At any point where water is withdrawn or accessed for purposes of livestock watering, the average of sulfate concentrations must not exceed 2,000 mg/L when measured at a representative frequency over a 30 day period.

2)	The results of the following equations provide sulfate water quality standards in mg/L for the specified ranges of hardness (in mg/L as CaCO₃) and chloride (in mg/L) and must be met at all times:

A)	If the hardness concentration of receiving waters is greater than or equal to 100 mg/L but less than or equal to 500 mg/L, and if the chloride concentration of waters is greater than or equal to 25 mg/L but less than or equal to 500 mg/L, then:

B)	If the hardness concentration of waters is greater than or equal to 100 mg/L but less than or equal to 500 mg/L, and if the chloride concentration of waters is greater than or equal to 5 mg/L but less than 25 mg/L, then:

3)	The following sulfate standards must be met at all times when hardness (in mg/L as CaCO₃) and chloride (in mg/L) concentrations other than specified in (h)(2) are present:

A)	If the hardness concentration of waters is less than 100 mg/L or chloride concentration of waters is less than 5 mg/L, the sulfate standard is 500 mg/L.
B)	If the hardness concentration of waters is greater than 500 mg/L and the chloride concentration of waters is 5 mg/L or greater, the sulfate standard is 2,000 mg/L.
C)	If the combination of hardness and chloride concentrations of existing waters are not reflected in subsection (h)(3)(A) or (B), the sulfate standard may be determined in a site-specific rulemaking pursuant to section 303(c) of the Federal Water Pollution Control Act of 1972 (Clean Water Act), 33 USC 1313, and Federal Regulations at 40 CFR. 131.10(j)(2).

309.101	Preamble
309.102	NPDES Permit Required
309.103	Application - General
309.104	Renewal
309.105	Authority to Deny NPDES Permits
309.106	Access to Facilities and Further Information
309.107	Distribution of Applications
309.108	Tentative Determination and Draft Permit
309.109	Public Notice
309.110	Contents of Public Notice of Application
309.111	Combined Notices
309.112	Agency Action After Comment Period
309.113	Fact Sheets
309.114	Notice to Other Governmental Agencies
309.115	Public Hearings on NPDES Permit Applications
309.116	Notice of Agency Hearing
309.117	Agency Hearing
309.118	Agency Hearing File
309.119	Agency Action After Hearing
309.120	Reopening the Record to Receive Additional Written Comment
309.141	Terms and Conditions of NPDES Permits
309.142	Water Quality Standards and Waste Load Allocation
309.143	Effluent Limitations
309.144	Federal New Source Standards of Performance
309.145	Duration of Permits
309.146	Authority to Establish Recording, Reporting, Monitoring and Sampling Requirements
309.147	Authority to Apply Entry and Inspection Requirements
309.148	Schedules of Compliance

309.151	Maintenance and Equipment
309.152	Toxic Pollutants
309.153	Deep Well Disposal of Pollutants (Repealed)
309.154	Authorization to Construct
309.155	Sewage Sludge Disposal
309.156	Total Dissolved Solids Reporting and Monitoring
309.157	Permit Limits for Total Metals
309.181	Appeal of Final Agency Action on a Permit Application
309.182	Authority to Modify, Suspend or Revoke Permits
309.183	Revision of Schedule of Compliance
309.184	Permit Modification Pursuant to Variance
309.185	Public Access to Information
309.191	Effective Date

309.201	Preamble
309.202	Construction Permits
309.203	Operating Permits; New or Modified Sources
309.204	Operating Permits; Existing Sources
309.205	Joint Construction and Operating Permits
309.206	Experimental Permits
309.207	Former Permits (Repealed)
309.208	Permits for Sites Receiving Sludge for Land Application
309.221	Applications - Contents
309.222	Applications - Signatures and Authorizations
309.223	Applications - Registered or Certified Mail
309.224	Applications - Time to Apply
309.225	Applications - Filing and Final Action By Agency
309.241	Standards for Issuance
309.242	Duration of Permits Issued Under Subpart B
309.243	Conditions
309.244	Appeals from Conditions in Permits
309.261	Permit No Defense
309.262	Design, Operation and Maintenance Criteria
309.263	Modification of Permits
309.264	Permit Revocation
309.265	Approval of Federal Permits
309.266	Procedures
309.281	Effective Date
309.282	Severability

AUTHORITY: Implementing Sections 13 and 13.3 and authorized by Section 27 of the Environmental Protection Act [415 ILCS 5/13, 13.3 and 27].

		1)	An applicant for a National Pollution Discharge Elimination System (NPDES) Permit shall file an application, in accordance with Section 309.223 ~~hereof~~, on forms provided by the Illinois Environmental Protection Agency (Agency). Such forms shall comprise the NPDES application forms promulgated by the U.S. Environmental Protection Agency for the type of discharge for which an NPDES Permit is being sought and such additional information as the Agency may reasonably require in order to determine that the discharge or proposed discharge will be in compliance with applicable state and federal requirements.

		2)	In addition to the above application forms, the Agency may require the submission of plans and specifications for treatment works and summaries of design criteria.

			A)	In addition to the above application forms, the Agency may require, pursuant to Section 39 of the Act, the installation, use, maintenance and reporting of results from monitoring equipment and methods, including biological monitoring. The Agency may require, pursuant to Section 39 of the Act, effluent toxicity testing to show compliance with 35 Ill. Adm. Code 302.621 and 302.630. If this toxicity testing shows the effluent to be toxic, the Agency may require pursuant to Section 39 of the Act further testing and identification of the toxicants ~~toxicant(s)~~ pursuant to 35 Ill. Adm. Code 302.210(a).

			B)	The following POTWs shall provide the results of valid whole effluent biological toxicity testing to the Agency:

				i)	All POTWs with design influent flows equal to or greater than one million gallons per day;

				ii)	All POTWs with approved pretreatment programs or POTWs required to develop a pretreatment program pursuant to 35 Ill. Adm. Code 310.Subpart E;

			C)	In addition to the POTWs listed in subsection (a)(3)(B), the Agency may require other POTWs to submit the result of toxicity tests with their permit applications, based on consideration of the following factors.