Sec. 18 AAC 83.435 - Water quality standards and state requirements
§ 18 AAC 83.435. Water quality standards and state requirements
(a) An APDES permit must include conditions to meet any applicable requirement in addition to or more stringent than promulgated effluent limitations guidelines or standards under 33 U.S.C. 1311, 1314, 1316, 1317, 1328, and 1345 if necessary to
(1) achieve water quality standards establish under 33 U.S.C. 1313, including state narrative criteria for water quality;
(2) attain or maintain a specified water quality through water quality-related effluent limits established under 33 U.S.C. 1312;
(3) incorporate any more stringent limitations, treatment standards, or schedule of compliance requirements established under federal or state statute or regulations in accordance with 33 U.S.C. 1311(b)(1)(C);
(4) ensure consistency with the requirements of a water quality management plan approved by EPA under 33 U.S.C. 1288(b);
(6) incorporate alternative effluent limitations or standards where warranted by fundamentally different factors under 40 C.F.R. 125.30 - 125.32, adopted by reference in 18 AAC 83.010.
(b) Effluent limitations in a permit must control all pollutants or pollutant parameters, either conventional, nonconventional, or toxic pollutants, that the department determines are or may be discharged at a level that will cause, have the reasonable potential to cause, or contribute to an excursion above any state water quality standard, including state narrative criteria for water quality.
(c) To determine whether a discharge causes, has the reasonable potential to cause, or contributes to an in-stream excursion above a narrative or numeric criteria within a state water quality standard, the department will use procedures that account for existing controls on point and nonpoint sources of pollution, the variability of the pollutant or pollutant parameter in the effluent, the sensitivity of the species to toxicity testing when evaluating whole effluent toxicity, and, if applicable, the dilution of the effluent in the receiving water.
(d) When the department determines, using the procedures in (c) of this section, that a discharge causes, has the reasonable potential to cause, or contributes to an in-stream excursion above the allowable ambient concentration of a state numeric criteria within a state water quality standard for an individual pollutant, the permit must contain effluent limits for that pollutant.
(e) When the department determines, using the procedures in (c) of this section, that a discharge causes, has the reasonable potential to cause, or contributes to an in-stream excursion above the numeric criterion for whole effluent toxicity, the permit must contain effluent limits for whole effluent toxicity.
(f) Except as provided in this subsection, when the department determines, using the procedures in (c) of this section, toxicity testing data, or other information, that a discharge causes, has the reasonable potential to cause, or contributes to an in-stream excursion above a narrative criterion within an applicable state water quality standard, the permit must contain effluent limits for whole effluent toxicity. Limits on whole effluent toxicity are not required if the department demonstrates in the fact sheet of the APDES permit, using the procedures in (c) of this section, that chemical-specific limits for the effluent are sufficient to attain and maintain applicable numeric and narrative state water quality standards.
(g) When the state has not established a water quality criterion for a specific chemical pollutant that is present in an effluent at a concentration that causes, has the reasonable potential to cause, or contributes to an excursion above a narrative criterion within an applicable state water quality standard, the department will establish effluent limits using one or more of the following options:
(1) establish effluent limits using a calculated numeric water quality criterion for the pollutant that the department demonstrates will attain and maintain applicable narrative water quality criteria and will fully protect the designated use; the criterion may be derived using a proposed state criterion, or an explicit state policy or regulation interpreting its narrative water quality criterion, supplemented with other relevant risk assessment data, exposure data, or other information that may include EPA's Water Quality Standards Handbookas revised as of August 1994, adopt by reference;
(2) establish effluent limits on a case-by-case basis, using EPA's water quality criteria, published under 33 U.S.C. 1314(a), supplemented if necessary by other relevant information;
(3) establish effluent limits on an indicator parameter for the pollutant of concern, if
(A) the permit identifies which pollutants are intended to be controlled by the use of the effluent limitation;
(B) the fact sheet sets out the basis for the limit, including a finding that compliance with the effluent limit on the indicator parameter will result in controls on the pollutant of concern that are sufficient to attain and maintain applicable water quality standards;
(C) the permit requires all effluent and ambient monitoring necessary to show that during the term of the permit the limit on the indicator parameter continues to attain and maintain applicable water quality standards; and
(D) the permit contains a reopener clause allowing the department to modify or revoke and reissue the permit if the limits on the indicator parameter no longer attain and maintain applicable water quality standards.
(h) When developing water quality-based effluent limits under this section, the department shall ensure that
(1) the level of water quality to be achieved by limits on point sources established under this section is derived from, and complies with, all applicable water quality standards; and
(2) effluent limits developed to protect a narrative water quality criterion, a numeric water quality criterion, or both, are consistent with the assumptions and requirements of any available wasteload allocation for the discharge prepared by the state and approved by EPA under 40 C.F.R. 130.7, as revised as of July 1, 2005.(Eff. 7/29/2006, Register 179; am 11/10/2007, Register 184)
Copies of EPA's Water Quality Standards Handbook, adopted by reference in 18 AAC 83.435(g) (1), may be obtained by contacting the U.S.E.P.A. Office of Water, Office of Science and Technology, 1200 Pennsylvania Avenue, NW, Washington, DC 20460 at (202) 566-0430, or by visiting the office's website at http://www.epa.gov/waterscience/standards/handbook/.
The following state regulations pages link to this page.