Section 207.03. Antidegradation evaluation procedure.  


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  • (1) General. When the department promulgates a less stringent criterion for a non-BCC pursuant to s. NR 105.02 (2) or revises a secondary value for a non-BCC due to an updated scientific database, any subsequent requests for increased permit limitations based on the revised criterion or secondary value will not be subject to the requirements of this chapter if the following occur:
    (a) The department determines that the increased limitations based on the changed criterion or secondary values will still maintain and protect the existing designated uses, and
    (b) The receiving water is not an outstanding resource water, an exceptional resource water subject to the requirements of sub. (4) (b) , or a water for which sub. (7) (c) applies.
    (2) Dissolved-based metal limitations. If a person requests an increased limitation based on a dissolved metals criterion pursuant to s. NR 106.07 (7) (b) , the request for an increased limitation will not be subject to the requirements of this chapter if the following occur:
    (a) The department determines that the increase limitations based on the changed criterion or secondary value will still maintain and protect the existing designated uses, and
    (b) The receiving water is not an outstanding resource water, an exceptional resource water subject to the requirements of sub. (4) (b) , or a water for which sub. (7) (c) applies.
    (3) Outstanding resource waters. If the department determines that a WPDES permit application proposes a new or increased discharge to outstanding resource waters, effluent limitations for substances in the new or increased portion of the discharge will be set equal to the background levels of these substances, upstream of, or adjacent to, the discharge site unless it is determined that for Great Lakes system waters, such limitations would result in significant lowering of water quality under s. NR 207.05 (4) (b) . Effluent limitations for those substances shall be determined in accordance with s. NR 207.04 .
    (4) Exceptional resource waters. If the department determines that a WPDES permit application proposes a new or increased discharge to exceptional resource waters, it shall review the application as follows:
    (a) For a proposed new discharge which is needed to prevent or correct either an existing surface or groundwater contamination situation, or a public health problem, water quality based effluent limitations shall be determined in accordance with sub. (6) .
    (b) For a proposed new discharge which is not needed to prevent or correct either an existing surface or groundwater contamination situation, or a public health problem, water quality based effluent limitations shall be set equal to the existing levels of these substances upstream of, or adjacent to, the discharge site.
    (c) For a proposed increased discharge, water quality based effluent limitations for the increased portion of the discharge shall be determined in accordance with sub. (6) .
    (d) Whenever effluent limitations determined in accordance with pars. (a) to (c) would result in any substance in the proposed new or increased discharge causing significant lowering of water quality as determined under s. NR 207.05 (4) (b) , effluent limitations shall be determined in accordance with s. NR 207.04 .
    (5) Great lakes system. If the department determines that a WPDES permit applicant proposes a new or increased discharge to the Great Lakes system, it shall establish effluent limitations using the procedures in ss. NR 207.04 and 207.05 ; except for proposed new or increased discharges of the pollutants identified in s. NR 102.12 (3) to waters of the Lake Superior basin. No new or increased discharge of those pollutants identified in s. NR 102.12 (3) may be permitted unless the applicant certifies at time of application that the proposed new or increased discharge is necessary after utilizing best technology in process or control using commercially available techniques with demonstrated performance levels for similar applications.
    (6) Fish and aquatic life waters. If the department determines that a WPDES permit application proposes a new or increased discharge to fish and aquatic life waters, it shall establish effluent limitations using the procedures in ss. NR 207.04 and 207.05 .
    (7) Waters listed in tables 3 through 8 in ss. NR 104.05 to 104.10. If the department determines that a WPDES permit application proposes a new or increased discharge to waters listed in tables 3 through 8 in ss. NR 104.05 to 104.10 , the following procedure shall apply:
    (a) The person proposing a new or increased discharge shall demonstrate to the department whether or not the discharge will result in:
    1. Significant lowering of water quality in downstream fish and aquatic life or Great Lakes system waters as determined under s. NR 207.05 ;
    2. Lowering of water quality of downstream outstanding resource waters;
    3. Lowering of water quality of downstream exceptional resource waters, except for a proposed increased discharge or a proposed new discharge necessary to correct or prevent an existing surface or groundwater contamination situation or a public health problem.
    (b) Sections NR 207.04 and 207.05 shall apply under either of the following circumstances:
    1. A proposed increased discharge would result in significant lowering of water quality of downstream fish and aquatic life waters, exceptional resource waters, or Great Lakes system waters; or
    2. A proposed new discharge which is necessary to correct or prevent an existing surface or groundwater contamination situation or a public health problem and would result in a significant lowering of downstream exceptional resource waters.
    (c) Effluent limitations shall be set to prevent a lowering of water quality under the following circumstances:
    1. The proposed new or increased discharge would result in a lowering of water quality to downstream outstanding resource waters; or
    2. A proposed new discharge not subject to par. (b) 2. would result in a lowering of water quality to downstream exceptional resource waters.
    (d) The remaining provisions of this chapter do not apply to situations relating to proposed new or increased discharges to waters listed in tables 3 through 8 in ss. NR 104.05 to 104.10 not covered by pars. (a) to (c) .
    (8) Noncontact cooling water. The requirements of subs. (1) and (2) apply to new or increased discharges of noncontact cooling water. The requirements of subs. (3) to (5) do not apply to new or increased discharges of noncontact cooling water which meet the following criteria:
    (a) The discharge contains no additives other than those necessary to provide a safe drinking water supply or those similar in type and amount to substances typically added to a public drinking water supply.
    (b) The discharge complies with the thermal criteria in ch. NR 102 .
    (c) The department has determined that the discharge does not contain concentrations of substances other than additives specified in par. (a) which will result in violations of water quality criteria established under ch. NR 105 or if the department has determined that the existing concentration of a toxic substance in the receiving water is greater than the water quality criterion in ch. NR 105 that the source of the water supply for the discharge is the same receiving water.
    (d) The discharge does not contain groundwater which is withdrawn from a location because of noncompliance with the standards in ch. NR 140 .
    (9) Permit conditions and reporting requirements. All WPDES permit applications for new or increased discharges reviewed under the procedures established in this chapter shall be subject to the permit conditions and reporting requirements in chs. NR 200 to 297 .
History: Cr. Register, February, 1989, No. 398 , eff. 3-1-89; renum. (1) to (7) to be (3) to (9) and am. (3), (4) (a) and (c), cr. (1) and (2), Register, August, 1997, No. 500 , eff. 9-1-97; CR 05-089 : am. (5) Register July 2006 No. 607 , eff. 8-1-06.