a)  Existing Uses
Uses actually attained in a surface water body or water body segment on or after November 28, 1975, whether or not they are included in the water quality standards, must be maintained and protected. Examples of degradation of existing uses of the waters of the State include:
 
1)  an action that would result in the deterioration of the existing aquatic community, such as a shift from a community of predominantly pollutant-sensitive species to pollutant-tolerant species or a loss of species diversity;
 
2)  an action that would result in a loss of a resident or indigenous species whose presence is necessary to sustain commercial or recreational activities; or
 
3)  an action that would preclude continued use of a surface water body or water body segment for a public water supply or for recreational or commercial fishing, swimming, paddling or boating.
 

b)  Outstanding Resource Waters
 
1)  Waters that are designated as Outstanding Resource Waters (ORWs) pursuant to 35 Ill. Adm. Code 303.205 and listed in 35 Ill. Adm. Code 303.206 must not be lowered in quality except as provided below:
 
A)  Activities that result in short-term, temporary (i.e., weeks or months) lowering of water quality in an ORW; or
 
B)  Existing site stormwater discharges that comply with applicable federal and State stormwater management regulations and do not result in a violation of any water quality standards.
 
2)  Any activity in subsection (b)(1)(A) or (b)(1)(B) that requires a National Pollutant Discharge Elimination System (NPDES) or a Clean Water Act (CWA) Section 401 certification must also comply with subsection (c)(2).
 
3)  Any activity listed in subsection (b)(1) or any other proposed increase in pollutant loading to an ORW must also meet the following requirements:
 
A)  All existing uses of the water will be fully protected; and
 
B)  Except for activities falling under one of the exceptions provided in subsection (b)(1)(A) or (B) above:
 
i)  The proposed increase in pollutant loading is necessary for an activity that will improve water quality in the ORW; and
 
ii)  The improvement could not be practicably achieved without the proposed increase in pollutant loading.
 
4)  Any proposed increase in pollutant loading requiring an NPDES permit or a CWA 401 certification for an ORW must be assessed pursuant to subsection (f) to determine compliance with this Section.
 
c)  High Quality Waters
 
1)  Except as otherwise provided in subsection (d) of this Section, waters of the State whose existing quality is better than any of the established standards of this Part must be maintained in their present high quality, unless the lowering of water quality is necessary to accommodate important economic or social development.
 
2)  The Agency must assess any proposed increase in pollutant loading that necessitates a new, renewed or modified NPDES permit or any activity requiring a CWA Section 401 certification to determine compliance with this Section. The assessment to determine compliance with this Section must be made on a case-by-case basis. In making this assessment, the Agency must:
 
A)  Consider the fate and effect of any parameters proposed for an increased pollutant loading.
 
B)  Assure the following:
 
i)  The applicable numeric or narrative water quality standard will not be exceeded as a result of the proposed activity;
 
ii)  All existing uses will be fully protected;
 

iii)  All technically and economically reasonable measures to avoid or minimize the extent of the proposed increase in pollutant loading have been incorporated into the proposed activity; and
 
iv)  The activity that results in an increased pollutant loading will benefit the community at large.
 
C)  Utilize the following information sources, when available:
 
i)  Information, data or reports available to the Agency from its own sources;
 
ii)  Information, data or reports supplied by the applicant;
 
iii)  Agency experience with factually similar permitting scenarios; and
 
iv)  Any other valid information available to the Agency.
 
d)  Activities Not Subject to a Further Antidegradation Assessment
 
The following activities will not be subject to a further antidegradation assessment pursuant to subsection (c) of this Section.
 
1)  Short-term, temporary (i.e., weeks or months) lowering of water quality;
 
2)  Bypasses that are not prohibited at 40 CFR 122.41(m);
 
3)  Response actions pursuant to the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA), as amended, corrective actions, pursuant to the Resource Conservation and Recovery Act (RCRA), as amended, or similar federal or State authority, taken to alleviate a release into the environment of hazardous substances, pollutants or contaminants which may pose a danger to public health or welfare;
 
4)  Thermal discharges that have been approved through a CWA Section 316(a) demonstration;
 
5)  New or increased discharges of a non-contact cooling water:
 
 
A)  without additives, except as provided in subsection (d)(5)(B), returned to the same body of water from which it was taken, as defined by 35 Ill. Adm. Code 352.104, provided that the discharge complies with applicable Illinois thermal standards; or
 
B)  containing chlorine when the non-contact cooling water is treated to remove residual chlorine, and returned to the same body of water from which it was taken, as defined in 35 Ill. Adm. Code 352.104, provided that the discharge complies with applicable Illinois thermal and effluent standards at 35 Ill. Adm. Code 302, 303, and 304;
 
6)  Discharges permitted under a current general NPDES permit as provided by 415 ILCS 5/39(b) or a nationwide or regional CWA Section 404 permit are not subject to facility-specific antidegradation review; however, the Agency must assure that individual permits or certifications are required prior to all new pollutant loadings or hydrological modifications that necessitate a new, renewed or modified NPDES permit or CWA Section 401 certification that affects waters of particular biological significance. Waters of particular biological significance may include streams listed in a 1991 publication by the Illinois Department of Conservation entitled “Biologically Significant Illinois Streams”; or

Constituent		AS (µg/L)	CS (µg/L)
Arsenic (trivalent, dissolved)		360 × 1.0* = 360	190 × 1.0* = 190
Boron (total)		40,100	7,600
Cadmium (dissolved)		*	*
		where A = -2.918 and B = 1.128	where A = -3.490 and B = 0.7852
Chromium (hexavalent, total)		16	11
Chromium (trivalent, dissolved)		where A = 3.688 and B = 0.8190	where A = 1.561 and B = 0.8190
Copper (dissolved)		where A = -1.464 and B = 0.9422	where A = -1.465 and B = 0.8545
Cyanide**		22	5.2
Fluoride (total)			, but shall not exceed 4.0 mg/L   where A = 6.0445 and B = 0.5394
		where A = 6.7319 and B = 0.5394
Lead (dissolved)		e A+B ln (H) × {1.46203 – [(ln(H))(0.145712)]}*	e A+B ln (H) × {1.46203 – [(ln(H))(0.145712)]}*
		where A = -1.301 and B = 1.273	where A = -2.863 and B = 1.273
Manganese (dissolved)		0.9812*   where A = 4.9187 and B = 0.7467	0.9812*   where A = 4.0635 and B = 0.7467
Mercury (dissolved)		2.6 × 0.85* = 2.2	1.3 × 0.85* = 1.1
Nickel (dissolved)
		where A = 0.5173 and B = 0.8460	where A = -2.286 and B = 0.8460
TRC		19	11
Zinc (dissolved)
		where A = 0.9035 and B = 0.8473	where A = -0.4456 and B = 0.8473
Benzene		4200	860
Ethylbenzene		150	14
Toluene		2000	600
Xylene(s)		920	360

 

         

 

Constituent		Unit	AS	CS	HHS
Arsenic (Trivalent, dissolved)		µg/L			NA
Boron (total)		mg/L	40.1	7.6	NA
Cadmium (dissolved)		µg/L			NA
			(0.041838)]}*	(0.041838)]}*
			where A = -3.6867 and B = 1.128	where A = -2.715 and B = 0.7852
Chromium (Hexavalent, total)		µg/L	16	11	NA
Chromium (Trivalent, dissolved)		µg/L			NA
			0.316*	0.860*
			where A = 3.7256 and B = 0.819	where A = 0.6848 and B = 0.819
Copper (dissolved)		µg/L			NA
			0.960*	0.960*
			where A = -1.700 and B = 0.9422	where A = -1.702 and B = 0.8545
Cyanide**		µg/L	22	5.2	NA
Fluoride (total)		µg/L	where A = 6.7319 and B = 0.5394	, but shall not exceed 4.0 mg/L	NA
				where A = 6.0445 and B = 0.5394
Lead (dissolved)		µg/L			NA
			(0.145712)]}*	(0.145712)]}*
			where A = -1.055 and B =1.273	where A = -4.003 and B = 1.273
Manganese (dissolved)		µg/L			NA
			where A = 4.9187 and B = 0.7467	where A = 4.0635 and B = 0.7467
Nickel (dissolved)		µg/L			NA
			0.998*	0.997*
			where A = 2.255 and B = 0.846	where A = 0.0584 and B = 0.846
Selenium (dissolved)		µg/L	NA	5.0	NA
TRC		µg/L	19	11	NA
Zinc (dissolved)		µg/L			NA
			0.978*	0.986*
			where A = 0.884 and B = 0.8473	where A = 0.884 and B = 0.8473
Benzene		µg/L	3900	800	310
Chlorobenzene		mg/L	NA	NA	3.2
2.4-Dimethylphenol		mg/L	NA	NA	8.7
2,4-Dinitrophenol		mg/L	NA	NA	2.8
Endrin		µg/L	0.086	0.036	NA
Ethylbenzene		µg/L	150	14	NA
Hexachloroethane		µg/L	NA	NA	6.7
Methylene chloride		mg/L	NA	NA	2.6
Parathion		µg/L	0.065	0.013	NA
Pentachlorophenol		µg/L			NA
			where A = -4.869 and B = 1.005	where A = -5.134 and B = 1.005
Toluene		µg/L	2000	610	51.0
Trichloroethylene		µg/L	NA	NA	370
Xylene(s)		µg/L	1200	490	NA

     [0.94412(1 + 10^x ) + 0.0559]

   Where: X = 0.09018 + 2729.92   -pH

          (T + 273.16)

1)  A Tier I Lake Michigan Basin Acute Aquatic Life Toxicity Criterion (LMAATC) or Tier II Lake Michigan Basin Acute Aquatic Life Toxicity Value (LMAATV) derived pursuant to procedures set forth in Sections 302.555, 302.560 or 302.563 at any time; or
 
2)  A Tier I Lake Michigan Basin Chronic Aquatic Life Toxicity Criterion (LMCATC) or Tier II Lake Michigan Basin Chronic Aquatic Life Toxicity Value (LMCATV) derived pursuant to procedures set forth in Section 302.565 as an average of four samples collected on four different days.
 
b)  Any combination of substances, including effluents, shall be deemed toxic to aquatic life if present in concentrations that exceed either subsection (b)(1) or (2) of this Section:
 
1)  No sample of water from the Lake Michigan Basin collected outside of a designated zone of initial dilution shall exceed 0.3 TU_a as determined for the most sensitive species tested using acute toxicity testing methods.
 
2)  No sample of water from the Lake Michigan Basin collected outside a designated mixing zone shall exceed 1.0 TU_c as determined for the most sensitive species tested using chronic toxicity testing methods.
 
3)  To demonstrate compliance with subsections (1) and (2) of this subsection (b), at least two resident or indigenous species will be tested. The rainbow trout will be used to represent fishes for the Open Waters of Lake Michigan and the fathead minnow will represent fishes for the other waters of the Lake Michigan Basin. Ceriodaphnia will represent invertebrates for all waters of the Lake Michigan Basin. Other common species shall be used if listed in Table I A of 40 CFR 136, incorporated by reference at Section 302.510, and approved by the Agency.
 
c)  Any substance shall be deemed toxic or harmful to wildlife if present in concentrations that exceed a Tier I Lake Michigan Basin Wildlife Criterion (LMWLC) derived pursuant to procedures set forth in Section 302.575 as an arithmetic average of four samples collected over four different days.
 
d)  For any substance that is a threat to human health through drinking water exposure only, the resulting criterion or value shall be applicable to only the Open Waters of Lake Michigan. For any substance that is determined to be a BCC, the resulting criterion shall apply in the entire Lake Michigan Basin. These substances shall be deemed toxic or harmful to human health if present in concentrations that exceed either of the following:
 
1)  A Tier I Lake Michigan Basin Human Health Threshold Criterion (LMHHTC) or Tier II Lake Michigan Basin Human Health Threshold Value (LMHHTV) based on disease or functional impairment due to a physiological mechanism for which there is a threshold dose below which no damage occurs as derived pursuant to procedures set forth in Section 302.585 as an arithmetic average of four samples collected over four different days; or
 
2)  A Tier I Lake Michigan Basin Human Health Nonthreshold Criterion (LMHHNC) or Tier II Lake Michigan Basin Human Health Nonthreshold Value (LMHHNV) based on disease or functional impairment due to a physiological mechanism for which any dose may cause some risk of damage as derived pursuant to procedures set forth in Section 302.590 as an arithmetic average of four samples collected over four different days.
 
e)  The derived criteria and values apply at all points outside of any waters in which mixing is allowed pursuant to Section 302.102 or Section 302.530.
 
f)  The procedures of this Subpart E set forth minimum data requirements, appropriate test protocols and data assessment methods for establishing criteria or values pursuant to subsections (b), (c), and (d) of this Section. No other procedures may be used to establish such criteria or values unless approved by the Board in a rulemaking or adjusted standards proceeding pursuant to Title VII of the Act. The validity and applicability of these procedures may not be challenged in any proceeding brought pursuant to Title VIII or X of the Act, although the validity and correctness of application of the numeric criteria or values derived pursuant to this Subpart may be challenged in such proceedings pursuant to subsection (g) of this Section.
 
g)  Challenges to application of criteria and values.
 
1)  A permittee may challenge the validity and correctness of application of a criterion or value derived by the Agency pursuant to this Section only at the time such criterion or value is first applied in its NPDES permit pursuant to 35 Ill. Adm. Code 309.152 or in an action pursuant to Title VIII of the Act for violation of the toxicity water quality standard. Failure of a person to challenge the validity of a criterion or value at the time of its first application to that person’s facility shall constitute a waiver of such challenge in any subsequent proceeding involving application of the criterion or value to that person.
 
2)  Consistent with subsection (g)(1) of this Section, if a criterion or value is included as, or is used to derive, a condition of an NPDES discharge permit, a permittee may challenge the criterion or value in a permit appeal pursuant to 35 Ill. Adm. Code 309.181. In any such action, the Agency shall include in the record all information upon which it has relied in developing and applying the criterion or value, and whether such information was developed by the Agency or submitted by the petitioner. THE BURDEN OF PROOF SHALL BE ON THE PETITIONER pursuant to Section 40(a)(1) of the Act.
 
3)  Consistent with subsection (g)(1) of this Section, in an action where alleged violation of the toxicity water quality standard is based on alleged excursion of a criterion or value, the person bringing such action shall have the burdens of going forward with proof and persuasion regarding the general validity and correctness of application of the criterion or value.
 
h)  Subsections (a) through (e) of this Section do not apply to USEPA registered pesticides approved for aquatic application and applied pursuant to the following conditions:
 
1)  Application shall be made in strict accordance with label directions;
 
2)  Applicator shall be properly certified under the provisions of the Federal Insecticide, Fungicide, and Rodenticide Act (7 U.S.C. 135 et seq. (1972));
 
3)  Applications of aquatic pesticides must be in accordance with the laws, regulations and guidelines of all State and federal agencies authorized by law to regulate, use or supervise pesticide applications;
 
4)  No aquatic pesticide shall be applied to waters affecting public or food processing water supplies unless a permit to apply the pesticide has been obtained from the Agency. All permits shall be issued so as not to cause a violation of the Act or of any of the Board's rules or regulations. To aid applicators in determining their responsibilities under this subsection (h), a list of waters affecting public water supplies will be published and maintained by the Agency's Division of Public Water Supplies.
 
(Source: Amended at 23 Ill. Reg. 11249, effective August 26, 1999)
 

3)  Wildlife BAF. The wildlife BAFs for an organic chemical shall be calculated using the following equations:
 
A)  For trophic level 3:
 
Wildlife BAF_WLTL3 = [(baseline BAF)(0.0646) +1] (f_fd)
 
B)  For trophic level 4:
 
Wildlife BAF_WLTL4 =[( baseline BAF)(0.1031) + 1] (f_fd)
 
Where:
 
0.0646 and 0.1031 are the standardized fraction lipid values for trophic levels 3 and 4, respectively, that are used to derive wildlife criteria
 
d)  Human health and wildlife BAFs for inorganic chemicals. For inorganic chemicals the baseline BAFs for trophic levels 3 and 4 are both assumed to equal the BCF determined for the chemical with fish.
 
1)  Human health. Measured BAFs and BCFs used to determine human health BAFs for inorganic chemicals shall be based on concentration in edible tissue (e.g., muscle) of freshwater fish.
 
2)  Wildlife. Measured BAFs and BCFs used to determine wildlife BAFs for inorganic chemicals shall be based on concentration in the whole body of freshwater fish and invertebrates.
 
(Source: Added at 21 Ill. Reg. 1356, effective December 24, 1997.)
 
Section 302.575  Procedures for Deriving Tier I Water Quality Criteria and Values in the Lake Michigan Basin to Protect Wildlife
 
The Lake Michigan Basin Wildlife Criterion (LMWC) is the concentration of a substance which if not exceeded protects Illinois wild mammal and bird populations from adverse effects resulting from ingestion of surface waters of the Lake Michigan Basin and from ingestion of aquatic prey organisms taken from surface waters of the Lake Michigan Basin. Wildlife criteria calculated under this Section protect against long-term effects and are therefore considered chronic criteria. The methodology involves utilization of data from test animals to derive criteria to protect representative or target species: bald eagle, herring gull, belted kingfisher, mink and river otter. The lower of the geometric mean of species specific criteria for bird species or mammal species is chosen as the LMWC to protect a broad range of species.
 
a)  This method shall also be used for non-BCCs when appropriately modified to consider the following factors:
 
1)  Selection of scientifically justified target species;
 
2)  Relevant routes of chemical exposure;
 
3)  Pertinent toxicity endpoints.
 
b)  Minimum data requirements:
 
1)  Test dose (TD). In order to calculate a LMWC the following minimal data base is required:
 
A)  There must be at least one data set showing dose-response for oral, subchronic, or chronic exposure of 28 days for one bird species; and
 
B)  There must be at least one data set showing dose-response for oral, subchronic, or chronic exposure of 90 days for one mammal species.
 
2)  Bioaccumulation Factor (BAF) data requirements:
 
A)  For any chemical with a BAF of less than 125 the BAF may be obtained by any method; and
 
B)  For chemicals with a BAF of greater than 125 the BAF must come from a field measured BAF or Biota-Sediment Accumulation Factor (BSAF).
 
c)  Principles for development of criteria
 
1)  Dose standardization. The data for the test species must be expressed as, or converted to, the form mg/kg/d utilizing the guidelines for drinking and feeding rates and other procedures in 40 CFR 132, incorporated by reference at Section 302.510.
 
2)  Uncertainty factors (UF) for utilizing test dose data in the calculation of the target species value (TSV);
 
A)  Correction for intermittent exposure. If the animals used in a study were not exposed to the toxicant each day of the test period, the no observed adverse effect level (NOAEL) must be multiplied by the ratio of days of exposure to the total days in the test period.
 
B)  Correction from the lowest observed adverse effect level (LOAEL) to NOAEL (UF_l). For those substances for which a LOAEL has been derived, the UF₁ shall not be less than one and should not exceed 10.
 
C)  Correction for subchronic to chronic extrapolation (UF_s). In instances where only subchronic data are available, the TD may be derived from subchronic data. The value of the UF_s shall not be less than one and should not exceed 10.
 
D)  Correction for interspecies extrapolations (UF_a). For the derivation of criteria, a UF_a shall not be less than one and should not exceed 100. The UF_a shall be used only for extrapolating toxicity data across species within a taxonomic class. A species specific UF_a shall be selected and applied to each target species, consistent with the equation in subsection (d).
 
d)  Calculation of TSV. The TSV, measured in milligrams per liter (mg/L), is calculated according to the equation:
 
TSV = { [TD x Wt] / [UF_a x UF_s x UF_l] } / { W + S [F_TLi x BAF_WLTLi] }
 
Where:
 
TSV = target species value in milligrams of substance per liter (mg/L).
TD = test dose that is toxic to the test species, either NOAEL or LOAEL.
UF_a = the uncertainty factor for extrapolating toxicity data across species (unitless). A species-specific UF_a shall be selected and applied to each target species, consistent with the equation.
UF_s = the uncertainty factor for extrapolating from subchronic to chronic exposures (unitless).
UF_l = the uncertainty factor for extrapolation from LOAEL to NOAEL (unitless)
Wt = average weight in kilograms (kg) of the target species.
W = average daily volume of water in liters consumed per day (L/d) by the target species.
F_TLi = average daily amount of food consumed by the target species in kilograms (kg/d) for trophic level i.
BAF_WLTLi = aquatic life bioaccumulation factor with units of liter per kilogram (L/kg), as derived from Section 302.570 for trophic level i.
 
e)  Calculation of the Lake Michigan Basin Wildlife Criterion. TSVs are obtained for each target species. The geometric mean TSVs of all mammal species is calculated and also of all bird species. The LMWC is the lower of the bird or mammal geometric mean TSV.
 
(Source: Amended at 27 Ill. Reg. 166, effective December 20, 2002)