Calculation of Water Quality Based Effluent Limitations (Issues 2, 28, 35)
The proposed rule creates a new methodology for calculating acute fish and aquatic life water quality based effluent limitations for toxic substances to address issue 28 in EPA’s July 18, 2011 letter. This change is necessary to conform to 40 CFR 122.44(d)(1)(vii)(A) and to ensure that Wisconsin’s permitting program is adequately protecting fish and aquatic life from acute toxicity effects in low stream flow situations. Specifically, the rule creates a mass balance approach to calculate acute fish and aquatic life water quality based effluent limitations in low stream flow conditions using 1-day 10-year hydrologically based low flow data (1Q10). This rule package also proposes changes to the specific provisions relating to the imposition of ammonia water quality based effluent limits in permits to address issue 35 in EPA’s letter. Under current laws, WPDES permits may not include ammonia limitations when they exceed 20 mg/L in the summer and 40 mg/L in the winter. This provision does not conform to the requirements in 40 CFR 122.44(d) and was determined invalid in MEA v. WDNR, Case No. 12CV3654. This rule revision proposes to delete this provision and base all permitting decisions for ammonia on a reasonable potential analysis in conformance with standard reasonable potential procedures for ammonia in ch. NR 106. Other proposed changes are included that are clarifying in nature. Specifically, the rulemaking seeks to clarify DNR’s ability to:
• Establish effluent limitations on internal waste streams (Issue 2 – 40 CFR 122.45 (h)) • Include mass limitations in addition to concentration based effluent limitations (Issue 2 – 40 CFR 122.44(f)) • Express water quality based effluent limitations for metals as total recoverable (Issue 2- 40 CFR 122.45(c)) Expression and Inclusion of Effluent Limits in WPDES Permits (Issue 2, 30, 34, 40 and 41 and 70)
The proposed rule modifies how water quality-based and technology-based effluent limitations are to be expressed in WPDES permits in order to comply with the requirements in 40 CFR 122.45(d) and applicable EPA guidance. Specifically, federal law and guidance requires that weekly average and monthly average limitations be included in WPDES permits for a given pollutant whenever limitations are determined to be necessary for continuous discharges subject to NR 210 - mainly publicly owned treatment works (POTWs). Daily maximum and monthly average limitations are required in WPDES permits for a given pollutant whenever limitations are determined to be necessary for continuous discharges not subject to NR 210 (e.g. industrial discharges). Changes to s. NR 106.07 are made to address this issue. There is an exception to 40 CFR 122.45(d). The Department may choose to not express limits as specified in 40 CFR 122.45(d) if it is impracticable. The Department made a demonstration for phosphorus limitations that expression of water quality based limits as specified in 40 CFR 122.45(d) was impracticable and USEPA approved the state’s impracticability demonstration. This rule package does not change the reasonable potential procedures in s. NR 106.05, Wis. Adm. Code. However, clarification was provided to explicate that any water quality-based effluent limitation, which has the reasonable potential to be exceeded, will be included in the WPDES permit. Alternative limitations may be included in a WPDES permit if a water quality standard is approved (Issue 40). This rule also clarifies the Departments authority to include a water quality based effluent limitation absent representative effluent data for a pollutant (Issue 70).
Whole Effluent Toxicity (WET) (Issue 2, 10, 42, and 74)
EPA over promulgated Wisconsin’s WET reasonable potential procedures used for discharges to the Great Lakes Basin on December 6, 2000 at 40 CFR 132.6(j). To conform to the requirements of the Great Lakes Initiative (40 CFR 132.6 (j), and 40 CFR part 132, Procedure 6 Appendix F, Paragraph D). This issue was included in issues 10 and 74 of EPA’s July 18th letter. The proposed rule modifies the reasonable potential process used for determining whether WET limitations are required in WPDES permits. Specifically, the proposed methodology utilizes a reasonable potential multiplication factor to convert the calculated effluent toxicity value to the estimated 95th percentile toxicity value. In addition to these changes, this rulemaking provides clarification to situations where chloride limitations are included in WPDES permits in lieu of WET limitations (Issue 42), and requires that WET permitting decisions be made whenever representative WET data is available (Issue 74). The proposed rule revision also seeks to clarify the averaging period of WET limitations (Issue 2). TMDL Development and Implementation (Issue 10)
In 2000, EPA disapproved of Wisconsin’s TMDL development program for toxic compounds, and other pollutants subject to GLI regulations, discharged into the Great Lakes Basin and promulgated 40 CFR 132.6(h). To conform to the requirements of 40 CFR 130.7 and the GLI at 40 CFR part 132, Appendix F, the proposed rule revision seeks to create NR 212 subchapter II to describe acceptable TMDL development procedures and to clarify procedures used to implement approved TMDLs in WPDES permits. Specifically, this rule provides general allocation procedures for TMDLs developed in the Great Lakes Basin as well as in other basins in the state, and provides procedures for deriving TMDL-based limitations, and public participation opportunities. These changes should address the TMDL component of issue 10 in EPA’s comment letter. Compliance Schedules (Issues 31, 32, 37, 40)
This rule revision proposes several changes to compliance schedule provisions for chloride, ammonia, and secondary values. These adjustments are intended to address part of issues 31, 32, 37 and 40 in EPA’s comment letter. These changes will clarify that a compliance schedule must be an enforceable sequence of actions or operations leading to compliance with an effluent limitation, and clarify that compliance schedules can only be granted if it is demonstrated that an existing point source can’t comply with a permit limitation upon permit reissuance.
Currently, Wisconsin Law allows additional time to be added to an ammonia compliance schedules at ss. NR 16.332 (2) (b) (2), NR 106.32 (3) (a) 4. a, and NR 106.37 (2-3), Wis. Adm. Codes, for the purposes of gathering additional data. As currently written, these provisions do not conform to the requirements of 40 CFR 122.47 and were determined invalid in Court Case No. 12CV3654 MEA vs. WDNR. This rule revision proposes to delete portions of these sections so that time cannot be added to a compliance schedule for the purposes of collecting additional data. Revisions are also proposed to clarify that a WPDES permit may be modified if an alternative ammonia limitation is approved by WDNR during the term of the permit or at the time of permit application. These modifications are subject to antidegradation requirements in ch. NR 207, Wis. Adm. Code. Although compliance schedules cannot be extended for the purposes of data collection in most instances, 40 CFR Part 132, Appendix F, Procedure 9, does allow time to be added to a compliance schedule for the purposes within the Great Lakes basin for limitations based on secondary criteria. Section NR 106.07(8), Wis. Adm. Code, which authorizes an extension in the compliance schedule for secondary values, was clarified that this extension is only available for point sources within the Great Lakes Basin. This change addresses issue number 32 in EPA’s letter. Other (Issues 36, 38 & 39 and 43)
Several changes are recommended to clarify EPA’s role in the approval of variances to water quality standards and clarifications to variance procedures for chloride and ammonia water quality based effluent limitations (issues 38, 39 and 43). These changes do not inhibit an individual permittees ability to request a chloride or ammonia variance, but are solely meant for clarification purposes. This rule also repeals the initial variance procedures for ammonia water quality based effluent limits as specified in s. NR 106.38, as these procedures are no longer applicable since the date for the initial variance has lapsed. Again, this change does not affect a point source discharger’s ability to request an ammonia variance. This rule revision also clarifies that increases in permit limitations that have become effective in a WPDES permit are subject to antidegradation procedures in ch. NR 207, Wis. Adm. Code. The specific rule provisions regarding the application of antidegradation procedures to increased ammonia limits was also deleted to address issue 36 in EPA’s comment letter. Other minor clarifications and corrections are also recommended in the proposed revisions. 6. Summary of, and Comparison with, Existing or Proposed Federal Statutes and Regulations:
The purpose of this rule package is to conform to existing federal regulations and improve continuity between state and federal requirements. No proposed federal regulations are applicable for this rule package. Specific federal laws that this rule seeks to conform with include:
• 40 CFR 122.44(d) which provides that WQBELs must be derived from and comply with water quality standards and designated uses; • 40 CFR 122.45 which addresses a variety of issues including the duration over which effluent limitations are to be expressed, internal waste streams, and mass limitations; • 40 CFR 122.47, which specifies the protocols and restrictions for establishing compliance schedules in WPDES permits for pollutants including ammonia and chloride; • 40 CFR Part 132, Appendix F, Procedure 9, which authorizes compliance schedule extensions within the Great Lakes Basin; • 40 CFR, Part 132, Appendix F, Procedure 3, pertaining to TMDLs in the Great Lakes Basin; • 40 CFR, Part 132, Appendix F, Procedure 5, pertaining to establishing WQBELs in the Great Lakes Basin; and • 40 CFR, Part 132, Appendix F, Procedure 6, pertaining to whole effluent toxicity in the Great Lakes Basin. Calculation of Water Quality Based Effluent Limitations (Issue 28, 35, 36, 40, 42, 43, 70, 74)
40 CFR 122.44(d)(1)(vii)(A) states that effluent limits must be established using a calculated numeric water quality criterion for the pollutant which will attain and maintain applicable narrative water quality criteria and will fully protect the designated use. Under existing Wisconsin law, acute water quality criteria may be exceeded in a stream or river in low stream flow situations. To address this apparent discrepancy, a new method is proposed for calculating water quality based effluent limitations based on acute toxicity effects to fish and aquatic life. Additionally, adjustments to the limit calculation procedures for chloride and ammonia were made to conform to these requirements. These changes specify that chloride and ammonia limitations will be included in WPDES permits whenever these limitation are determined to be necessary through reasonable potential. The proposed rules also address how WET limitations and chloride limitation interact to meet the requirements of 40 CFR 122.44(d). Expression and Inclusion of Effluent Limits in WPDES Permits (Issue 2)
40 CFR 122.45(d) stipulates that permit limitations be expressed as weekly average and monthly average limitations for continuous POTW discharges, and maximum daily limitations and monthly average limitations for all other continuous discharges, unless impracticable. Additionally, EPA provides a methodology for calculating and expressing limitations in conformance with 40 CFR 122.45(d) in the “Technical Support Document for Water Quality-based Toxic Control” (March 1991). The proposed rule revisions comply with these requirements by creating a methodology and process for calculating water quality-based effluent limits and expressing all permit limits in Wisconsin. This methodology draws from the Technical Support Document as well as the toxicological data and intent of the water quality criteria to ensure that permit limits are adequately protective of Wisconsin’s surface water and designated uses, without being overly restrictive. This rule also maintains the ability to express limitations through other averaging periods if an impracticability demonstration is made. 40 CFR 122.45 also includes requirements for establishing effluent limitations for internal waste streams, mass limitations, and other issues. Revisions are proposed to include these federal requirements. Whole Effluent Toxicity (Issue 10)
The GLI requires specific reasonable potential procedures be used to determine the need for WET limitations for point source discharges in the Great Lakes Basin at 40 CFR part 132, Procedure 6 of Appendix F. EPA over promulgated Wisconsin’s WET reasonable potential procedures in the Great Lakes Basin on December 6, 2000 at 40 CFR 132.6(j) because Wisconsin’s existing program does not comply with these requirements. The proposed rule revision modifies the reasonable potential procedures used for WET limitations to address this over promulgation. TMDL Development and Implementation (Issue 10)
The GLI requires specific procedures for developing and implementing TMDLs in the Great Lakes Basin at 40 CFR part 132, Procedure 3 of Appendix F. TMDL procedures are also specified at 40 CFR 130.7. In 2000, EPA disapproved of Wisconsin’s TMDL development program for toxic compounds, and other pollutants regulated in the GLI and discharged into the Great Lakes Basin and consequently promulgated 40 CFR 132.6(h). The proposed rule revision creates a subchapter in NR 212 to address this over promulgation and to conform to the federal requirements in 40 CFR 132.6(h) and 40 CFR 130.7. Compliance Schedules (Issues 31, 32, 37, 40)
Section 502(17) of the Clean Water Act, 33 U.S.C. 1362(17), defines a compliance schedule as an “enforceable sequence of actions or operations leading to compliance with an effluent limitation”. 40 CFR 122.47 also establishes requirements for compliance schedules. A demonstration or data collection that is intended to justify a change in an effluent limitation is not an action leading to compliance with a final effluent limitation under the CWA. Therefore, the proposed rule revision recommends changes to the ammonia and chloride compliance schedule procedures to conform to these requirements. 40 CFR Part 132, Appendix F, Procedure 9, does allow time to be added to a compliance schedule for these purposes for dischargers within the Great Lakes basin that have limitations based on secondary criteria. Therefore, revisions are also recommended to the compliance schedule program for secondary values to limit this authority to only discharges in the Great Lakes Basin in conformance with federal law. Other
A variance is a revision to a water quality standard that must be supported on the basis of one of the factors specified in 40 CFR 131.10(g), and requires EPA review and approval before it can be implemented (40 CFR 131.21(c)). This rule revision proposes to clarify EPA’s role in reviewing variances, and also provides clarification on chloride and ammonia variance procedures. 7. Comparison with Similar Rules in Adjacent States:
All the other U.S. EPA Region 5 states (Illinois, Indiana, Michigan, Minnesota and Ohio) are subject to the U.S. EPA regulations. Iowa and portions of the Region 5 states that do not drain to the Great Lakes are not subject to Great Lake Initiative requirements. Although Wisconsin’s program is consistent with federal law, it is not directly comparable to the Iowa implementation program, as Wisconsin is subject to these additional federal requirements. A brief comparison of key states is provided below on the six key issues addressed in the proposed rule revision.
Calculation of Water Quality Based Effluent Limitations
All region 5 states and Iowa appear to use the FAV and mass balanced approach for calculating water quality based effluent limitations based acute toxicity effects on fish and aquatic life.
Iowa, Indiana, and Ohio use a 1Q10 mass balance based approach for calculating water quality based effluent limitations based acute toxicity effects on fish and aquatic life. Illinois, Michigan, and Minnesota also use a mass balance based approach for calculating these water quality based effluent limitations but do not specify the specific stream flow data used in this equation in code. After a cursory review of available guidance, it appears that 7Q10 data are used or alternative flow based on best professional judgment. Additionally, none of these states has a 20 mg/L or 40 mg/L cap for ammonia limitations specified in code. It is noted, however, that Michigan does have specific ammonia limitations codified for categories of point source discharges. Therefore, repealing this provision would make Wisconsin’s program consistent with EPA regulations, the other Region 5 states, and Iowa.
Expression and Inclusion of Effluent Limits in WPDES Permits
Michigan, Illinois, Ohio, and Iowa express water quality based effluent limitations derived from acute toxicity impacts on fish and aquatic life as daily maximum limitations, and water quality based effluent limitations derived from chronic toxicity as monthly average limitations. Statistical methods are not specified in Ohio or Iowa for converting chronic water quality standards for toxic substances to monthly average permit limitations. Michigan and Illinois, on the other hand, chose to codify portions of the Technical Support Document to convert chronic water quality standards to monthly average limitations. Human health limitations are solely expressed as monthly average limitations in these states.
These states do not provide a codified methodology for creating additional permit limitations if the triggered water quality based effluent limitations are not sufficient to meet the requirements of 122.45(d). Minnesota and Indiana’s approach for expression and inclusion of effluent limitations in permits is structured identically to 122.45(d). Minnesota does not provide a methodology in code for calculating these limitations. Indiana, on the other hand, chose to codify EPA’s recommending methodology in the Technical Support Document. The proposed rule revisions closely mirrors Indiana’s approach for calculating and expressing permit limits as this approach reflects the requirements of 122.45(d) as well as EPA guidance. However, the proposed methodology also considers the averaging period used to deriving the toxicity criteria and, therefore, differs slightly from the Indiana approach.
Whole Effluent Toxicity
Indiana, Michigan, and Ohio’s WET reasonable potential procedures were also over promulgated by EPA on September 5, 2000 at 40 CFR 132.6(c). Indiana and Michigan updated their WET reasonable potential procedures to be consistent with the GLI since this over promulgation. Michigan also specifies when chloride or other pollutant limitations can be used in lieu of WET limitations similar to Wisconsin. Other states do not specify this authority in code. It is not clear whether this action has satisfied EPA at this time. Illinois chose to incorporate the requirements of Procedure 5 of Appendix F at 40 CFR 132 by reference. Illinois uses an alternative method for WET data outside of the Great Lakes basin however while Wisconsin is proposing to apply the same procedure statewide. Iowa does not appear to have specific WET procedures in code. Iowa is not subject to the GLI and is, therefore, not subject to the same federal restrictions as Wisconsin. TMDL Development and Implementation
TMDL develop and implementation procedures vary among the Region V states. Minnesota, for example, does not have any procedures in code for specifying TMDL development or implementation at this time. Michigan and Indiana have promulgated general principles and procedures for developing and implementing TMDLs that appear to align with the requirements of the GLI. Indiana’s program solely applies to TMDLs within the Great Lakes Basin, and not to discharges outside of the Basin. Indiana does specify general provisions for calculating wasteload allocations in the absence of a TMDL and preliminary wasteload allocations for the entire state, however. Ohio’s program incorporates by reference the requirements of 40 CFR 130.7. Additional specificity is provided in Ohio’s TMDL procedures, but these do not align directly with the requirements for the GLI. Illinois TMDL program in the Great Lakes Basin is not specific at this time, and was over promulgated by EPA on September 5, 2000 at 40 CFR 132.6(b). Iowa does not appear to have specific TMDL procedures in code. Iowa is not subject to the GLI and is, therefore, not subject to the same federal restrictions as Wisconsin. Compliance Schedules
All Region V states and Iowa specify their authority for granting compliance schedules for toxic substances including ammonia and chloride, in code. This authority aligns with the CWA, but these programs have varying specificity provided in code. For example, Michigan and Illinois have specific measures and time frames specified in code for their compliance schedules. They also provide that a “reopener” clause can be included in a NPDES permit to modify the permit pending new data, but these data collection efforts are not authorized as part of the compliance schedule. Additionally Michigan and Illinois allow time extensions for the purposes of data collection in compliance schedule for water quality based effluent limitations derived secondary values. Illinois does not limit this extension to only Great Lake discharges, however. Indiana and Minnesota’s compliance schedule authority, on the other hand, is more generically stated compared to Michigan and Illinois, and solely defines what a compliance schedule is and what the maximum duration of a compliance schedule may be.
Other
All water quality standard variances must be approved by EPA. Some states including Illinois, Iowa, and Minnesota do not specify this approval authority specifically in code. Other states such as Michigan and Indiana do specify this authority.
