Illinois Administrative Code › Title 35 - ENVIRONMENTAL PROTECTION › Part 352 - PROCEDURES FOR DETERMINING WATER QUALITY BASED PERMIT LIMITATIONS FOR NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM DISCHARGERS TO THE LAKE MICHIGAN BASIN › Subpart D - ASSESSMENT OF REASONABLE POTENTIAL TO EXCEED WATER QUALITY STANDARDS, CRITERIA, AND VALUES › Section 352.430 - Instances Requiring Effluent Limits, Other Conditions, or Additional Data

Current through Register Vol. 48, No. 28, July 12, 2024
The Agency will consider the following factors when
				  determining whether further data needs to be gathered in order to decide if a
				  reasonable potential to exceed water quality standards exists. These factors
				  may also warrant inclusion of a permit limit for a substance or substances that
				  do not display a reasonable potential to exceed through the analysis of
				  Sections 352.420 through
				  352.425.
a) The facility's effluent is subject to
				federal categorical limits under 40 CFR 405 through 471 for the
				substance.
b) A substance(s) is
				present in the raw wastewater in significant quantities such that treatment at
				the facility is designed to remove that substance.
c) A substance is discharged in quantities
				that are sufficient to warrant limits in the permit due to batch or highly
				variable waste generation processes wherein substances are potentially
				discharged infrequently or sporadically and therefore may avoid detection by
				intermittent sampling of the final effluent.
d) The facility has a record of spill events
				involving certain substances and there is evidence that those substances are
				discharged in quantities that are sufficient to merit inclusion of permit
				limits.
e) Historical information
				or the knowledge of Agency field inspectors indicate that a potential for
				discharge of a substance exists and there is evidence that the substance would
				be discharged in quantities sufficient to merit inclusion of permit
				limits.
f) For each pollutant
				listed in Table 6 to 40 CFR 132(1996) which a permittee reports as known or
				believed to be present in its discharge and for which data sufficient to
				calculate tier II values for noncancer human health and acquatic life do not
				exist all of the following provisions apply:
1) The Agency shall use all available,
				relevant toxicity information to estimate ambient screening values for the
				pollutant that will protect humans from noncancer health effects and aquatic
				life from acute and chronic effects.
2) Using the provisions specified in Section
				352.423,
				the Agency shall develop a PEL based on the estimated ambient screening value
				as determined in subsection (f)(1) of this Section, and compare the PEL with
				the PEQ. If the PEQ exceeds the PEL, then the Agency shall generate the minimum
				data necessary to derive tier II values for noncancer human health and aquatic
				life.
3) The data generated in
				accordance with subsection (f)(2) of this Section shall be used to calculate
				water quality values. The values shall be used in calculating a PEL pursuant to
				Section
				352.423
				for the purpose of determining whether a WQBEL must be included in the permit.
				If the Agency finds that the PEQ exceeds the PEL, the Agency shall follow the
				procedures under Section
				352.424
				to determine whether a WQBEL must be established in the permit.