Antidegradation procedures for individual WPDES permits

Antidegradation procedures for individual WPDES permits. (1) General. To be consistent with the antidegradation policy stated under s. NR 102.045 , the department shall conduct a review of any proposed new or increased discharge under an individual WPDES permit and determine whether it will lower water quality in a surface water of the state. If so, the department shall determine whether a practicable alternative would prevent or lessen any lowering of water quality and whether lowering is necessary to support important social or economic development in the area where the waters are located. The applicant shall submit the information and supporting information required under this subchapter using department-approved forms and following applicable instructions. The department’s determination shall be based upon a review of the antidegradation application materials, including, if applicable, an analysis of alternatives under sub. (8) (c) , a social importance analysis or economic importance analysis under sub. (8) (b) , and a demonstration that resulting water quality will be adequate to fully protect existing uses. The department shall seek and consider public input and make a determination as to whether the antidegradation requirements have been satisfied under sub. (9) (c) and (d) . (2) Applicant screening submittal. (a) The purpose of the applicant’s screening submittal is to enable the department to review the applicant’s available information and notify the applicant of what additional information, if any, will be required for submittal of a complete antidegradation application during any of the actions specified under s. NR 207.011 (2) (a) . A person proposing a new or increased discharge shall submit all of the following screening information to the department as early as possible prior to any of the actions specified under s. NR 207.011 (2) (a) : 1. The proposed location of the new or increased discharge and identification of the receiving water. 2. A list of the parameters that are proposed or expected to change in concentration, level, or loading in the new or increased discharge. 3. The expected maximum and average concentrations in the effluent for parameters listed under subd. 2. that have a numeric or narrative water quality criterion, secondary value, or TMDL target, if different from data already submitted to the department through regular permit monitoring. If pilot testing data are available, that data shall also be submitted. 4. The projected new effluent flow rate or increase in effluent flow as defined under s. NR 106.06 (4) (d) , if different from current flow data. 5. A demonstration that it is not practicable for the facility’s currently installed treatment technology to treat the proposed new or increased discharge to levels that will meet existing effluent limitations. 6. An indication of whether the applicant prefers to collect water quality data from the receiving water and downstream waters as specified under sub. (4) , or whether the applicant requests that the department determine parameter concentrations, levels, or loads in the receiving water, in the event that the department determines under sub. (3) (b) that sufficient receiving water data are not available for the parameters listed under subd. 2. to complete the screening process. (b) In addition to the information submitted under par. (a) , the applicant may also submit water quality data for the receiving water and downstream waters or data to be considered in the department’s receiving water flow rate determination. (3) Department antidegradation screening. Based on materials submitted by the applicant under sub. (2) and other relevant information available for the department’s review, the department shall conduct an antidegradation screening for any discharge under this subsection. The department shall assess the following information to determine whether a lowering of water quality may be permissible, and if so, whether it requires further antidegradation review under subs. (5) to (9) : (a) New or increased discharge determination. The department shall determine whether the proposed discharge meets the definition of a new discharge or an increased discharge under s. NR 207.021 (3) and (4) . The department shall also determine whether the applicant has demonstrated that it is not practicable for the facility’s currently installed treatment technology to treat the proposed new or increased discharge to levels that will meet existing effluent limitations. (b) Water quality data screening. The department shall determine whether sufficient water quality data for the receiving and downstream waters are available to determine the applicable waterbody categories under par. (c) and, if applicable, to calculate the assimilative capacity used for the significance determination under sub. (8) . If sufficient water quality data are not available, the applicant or the department shall follow the steps under sub. (4) to compile the necessary data. (c) Receiving water determination. If the proposed discharge is a new or increased discharge, the department shall determine which high quality or non-high quality categories, defined under s. NR 102.045 (2) (b) and (c) , apply to the receiving water and downstream waters affected by the proposed discharge. After the appropriate waterbody categories are identified, the department shall determine whether a lowering of water quality for each applicable category is prohibited or may be permissible under subs. (5) to (8) . (d) Pollutants that are allocated under an EPA-approved TMDL. For a proposed new or increased discharge of a pollutant to a receiving water where the pollutant has an allocation under an EPA-approved TMDL, the department shall use the following procedures to determine whether a lowering of water quality may be permissible, and if so, whether it requires further antidegradation review under subs. (5) to (9) : 1. If an effluent limitation for the pollutant is in effect, a request for an increased discharge is subject to further antidegradation review under subs. (5) to (9) . If a limitation for the pollutant has not taken effect, a permittee may receive an effluent limitation based on a TMDL wasteload allocation for the pollutant without further antidegradation review. 2. If there is a proposed new discharge to a receiving or downstream water with an approved TMDL or a proposed increased discharge of a pollutant that would exceed an effluent limitation based on a TMDL wasteload allocation, the department may consider a lowering of water quality under the antidegradation procedures under subs. (5) to (9) if there is reserve capacity available for the pollutant. 3. If there is no reserve capacity available for the pollutant, the department may not approve a new or increased discharge of the pollutant unless the new or increased discharge is offset through a trade authorized under s. 283.84 , Stats., or other means such that the discharge does not result in a lowering of water quality. 4. An antidegradation demonstration under this subchapter is not required if a proposed increased discharge will not result in an effluent concentration above the applicable numeric or narrative water quality criteria for the receiving or downstream waters, and if the proposed discharge is specifically allowed under an EPA-approved TMDL because it does not cause or contribute to an impairment. (e) Other impacts to the receiving water. 1. If the determinations under pars. (a) to (d) indicate that the proposed new or increased discharge may be considered by the department and requires further antidegradation review, the department shall determine whether point source and state-regulated nonpoint source requirements are being administered in accordance with state law for discharges to the receiving water to ensure that the antidegradation policy under s. NR 102.045 (5) (c) is satisfied. To make the determination under this paragraph, the department shall complete all of the following: a. Identify point sources and state-regulated nonpoint sources that are discharging a pollutant of concern under the antidegradation review that may be negatively impacting the quality of the receiving water. b. If pollutant sources are identified under subd. 1. a. , to the extent feasible given agency resources, evaluate whether there are noncompliance issues with point source WPDES permits or nonpoint source performance standards and prohibitions under ch. NR 151 . The department shall also evaluate existing data that may inform whether receiving water quality in the area of the proposed discharge has improved or degraded over time. If there are significant noncompliance issues with point or nonpoint sources that are causing a negative impact to the receiving water, the department shall to the extent feasible and in consideration of available resources, initiate actions required under state law. 2. If the department finds that the antidegradation policy is met under subd. 1. , the proposal for a new or increased discharge shall proceed through antidegradation review under this subchapter. If not, the department may not authorize the proposed lowering of water quality and will notify the applicant. (f) Eligibility for streamlined review. If requirements under sub. (8) will apply, the department shall use the information obtained during the screening process to determine whether the applicant is eligible for a streamlined review under sub. (8) (a) . (g) Notification. If there is potential to lower water quality, the department shall notify the applicant of its findings under pars. (a) to (f) and shall specify one or more of the following: 1. That requirements for an antidegradation review under subs. (5) to (9) apply. 2. That further information is needed to complete the screening process or antidegradation review, and what additional information may be required. 3. That the proposed lowering of water quality is prohibited under this section, in which case the department shall issue a preliminary determination under sub. (9) (b) . (4) Water quality data. The department shall determine existing concentrations or levels of parameters of concern in the receiving water and downstream waters based on water quality data that are sufficient, representative, and credible, as described in this subsection. If there is insufficient existing representative ambient water quality data for this determination, the department may determine background levels by collecting water quality data during the next sampling season or using other scientifically defensible methods such as data from representative sites in watersheds with similar characteristics. If the applicant chooses to obtain and submit sufficient data for the department’s determination, the applicant shall collect data in the receiving and downstream waters in accordance with the department’s monitoring and quality assurance protocols for each parameter. The department shall determine existing concentrations or levels of parameters of concern and the remaining assimilative capacity for such parameters in the receiving waters, based on the following: (a) Determinations shall be made using the most recent representative data available, not to exceed 10 years old unless the department determines that those levels are still representative. If the department determines that existing data are no longer representative of current conditions based on changes at the local or watershed scale, more recent data may be required to ascertain current water quality. (b) If new water quality samples are collected, they shall be collected consistent with the following locations: 1. For waters with unidirectional flow, upstream of the discharge site but outside the direct influence of the discharge. 2. For waters without unidirectional flow such as lakes or impoundments, adjacent to the discharge site but outside the direct influence of the discharge. (c) The level of baseline water quality data necessary for department review shall be relative to the size of the project, characteristics of the proposed discharge, and the characteristics of the receiving water including special management or habitat designations, as applicable. (d) When evaluating whether the available data is representative, sufficient, and credible or whether additional information may be necessary, the department shall consider all relevant factors, including the following: 1. The sensitivity of the receiving water to degradation of existing or designated uses. 2. The parameters of concern in the proposed discharge. 3. The available dilution or assimilative capacity of the receiving water for the proposed discharge, including the impacts of authorized discharges. 4. The representativeness of any surrogate water information proposed for baseline water quality relative to the receiving water under review, including geographic, hydrologic, geologic, water use, and water quality characteristics. 5. The validity of any baseline concentrations assumed to be below detection levels. 6. The quantity, date of analysis, analytical method, detection level, and spatial and temporal scope of any submitted data. 7. Applicable seasonal or natural variability. (e) The department may use water quality modeling on a case-by-case basis to determine whether downstream waters are likely to be lowered in quality by a proposed new or increased discharge. (5) Non-high quality waters. For receiving waters that the department determines to be non-high quality waters as defined under s. NR 102.045 (2) (c) , standard limit calculation procedures under chs. NR 102 , 104 , 106 , 210 , and 217 apply. If a surface water is listed on the section 303 (d) list as not attaining a water quality criterion for a specific parameter or the department has data showing that it is not attaining a water quality criterion for a parameter, there shall be no lowering of water quality with respect to the concentration, level, or loading of the parameter, unless it is allocated as part of the reserve capacity or wasteload allocation under a TMDL approved by the U.S. EPA or as allowed under s. NR 217.13 (8) . If a new or increased discharge to a non-high quality water would lower water quality in a high quality water downstream, an antidegradation review is required for the downstream water in accordance with subs. (3) to (9) . (6) Requirements for outstanding state or national resource waters and exceptional resource waters. (a) Outstanding state or national resource waters. For proposed new or increased discharges to or impacting downstream outstanding resource waters or outstanding national resource waters, the department may not approve any change in effluent concentration, level, or loading unless the change will improve water quality. The department shall set limits for an approvable new or increased discharge equal to or better than background concentrations upstream of or adjacent to the discharge site, or the water quality criterion, whichever is more protective. (b) Exceptional resource waters. For proposed new or increased discharges to or impacting downstream exceptional resource waters, the department shall set limits equal to or better than background concentrations upstream of or adjacent to the discharge site, or at the water quality criterion, whichever is more protective. If lowering water quality is necessary to prevent or correct contamination or a public health problem, the applicant and the department shall follow the procedures under sub. (8) . In these cases, permit limits may not exceed pollutant levels demonstrated to be needed by the facility. (7) Great Lakes system waters. The department shall prohibit new or increased discharges of BCCs to a Great Lakes system water unless the applicant demonstrates the necessity to lower water quality through an antidegradation review following the procedures under sub. (8) . For a proposed new or increased discharge to the Great Lakes system of a BCC that is already exceeding its water quality criterion, permit limitations shall be set no higher than the criterion and may not exceed the amount demonstrated to be needed by the facility. (8) Other high quality waters. For a new or increased discharge to a high quality water other than those specified under sub. (6) , all of the following procedures apply: