CR_15-085 Expression of limits, whole effluent toxicity, TMDL development and implementation, and other aspects of the WPDES permitting program

ORDER OF THE STATE OF WISCONSIN NATURAL RESOURCES BOARD

REPEALING, RENUMBERING, RENUMBERING AND AMENDING, AMENDING , REPEALING AND RECREATING AND CREATING RULES

The statement of scope for this rule, WT-11-12, was approved by the Governor on May 29, 2012 published in Register 678 A on June 14, 2012 and approved by the Natural Resource Board on June 27, 2012.

The Wisconsin Natural Resources Board proposes an order to repeal NR 106.03 (10), NR 106.03 (11), NR 106.05 (8) note, NR 106.145 (9) (b) note, NR 106.32 (2) (b) (2), NR 106.32 (3) (a) 4. a. note, NR 106.34, NR 106.36 (3) note, NR 106.36 (4), NR 106.37 (1) (note), NR 106.37 (2) note, NR 106.37 (3) and NR 106.37 (3) note, NR 106.38, NR 106.88 (2) note, NR 106.88(4), NR 106.88(6), NR 106.91 note; to renumber NR 106.03 (1); to amend NR 106.03 (13), NR 106.03(14), NR 106.05 (1) (c), NR 106.06 (3) (c) (intro), NR 106.06(3)(c)4., NR 106.06 (3) (c) 5., NR 106.06 (7), NR 106.07 (8), NR 106.09 (3) (b), NR 106.09 (3) (b) 1., NR 106.115 table 1 (title) and Table 2 (title), NR 106.32 (2) (b) and 2., NR 106.32 (3) (a) 4. a., NR 106.36 (3)Table 1(title), NR 106.37 (1), NR 106.55 (6) (a) Table 1 (title), NR 106.62, NR 106.75, NR 106.83 (2) (c), NR 106.87 (1), NR 106.91, NR 212.01, NR 212.02 (2), NR 212.03, NR 212.03 (3), (12), (22), and (24), NR 212.12 (2) (d), NR 212.40 (2), (b), and (c), NR 212.60 (1), (b), (d), (e), and (g), NR 212.70 (1) (a) and (b), NR 212.70 Table 5m (title), NR 217.14 (2) and (3); to repeal and recreate NR 106.05 (8), NR 106.06 (3) (b), NR 106.07 (2), NR 106.07 (3), NR 106.07 (4), NR 106.07 (5), NR 106.08, NR 106.09 (2) (e), NR 106.09 (3) (c), NR 106.33, NR 106.37 (2), NR 106.8 8(1), NR 106.88 (2), NR 106.88 (3), NR 106.88 (5), NR 106.89, NR 212.02 (1); and to create NR 106.03 (1g), NR 106.03 (2m), NR 106.03 (2m) note, NR 106.03 (5m), NR 106.03 (13m), NR 106.04 (3m), NR 106.06 (3) (bm), NR 106.06 (4) (f), NR 106.07 (1) (title), NR 106.07 (2) note, NR 106.07 (3) note, NR 106.07 (4) note, NR 106.07 (5m) and (title), NR 106.07 (6) (title), NR 106.07 (7) (title), NR 106.07 (8) (title), NR 106.07 (9) (title), NR 106.07 (10) and (title), NR 106.09 (2) (f), NR 106.09 (3) (c), NR 106.09 (3) (d), NR 106.1 (note), NR 106.32 (2) (e), NR 205.03 (9g), NR 205.065 and 205.066, NR 212 Subchapter I (title), NR 212 Subchapter II (title), NR 212 Subchapter II and (title) relating to WPDES permit implementation, TMDL implementation, and TMDL development and affecting small business.

WT - 11 - 12

Analysis Prepared by the Department of Natural Resources

1. Statute I nterpreted: Chapter 283 , Stats.

2. Statutory A uthority: Sections 227.11 , 283.11 , 283.13 , 283.15 , 283.31 , 283.35 , 283.41 , and 283.45 , Stats.

3. Explanation of Agency A uthority:

Chapter 283 , Stats., grants authority to the department to establish, administer and maintain a Wisconsin Pollutant Discharge Elimination System (WPDES) Permit Program consistent with the requirements of the federal water pollution control act of 1972, commonly known as the Clean Water Act. More specifically, s. 283.11(1) , Stats., authorizes the department to promulgate by rule effluent limitations and standards for any category of point sources established by the U.S. Environmental Protection Agency (EPA) and for which EPA has promulgated effluent limitations and standards. In addition, s. 283.13 , Stats., authorizes the department to establish technology-based effluent limitations as well as more stringent water quality-based effluent limitations to comply with any state or federal law, rule or regulation. Section 283.15 , Stats., authorizes variances to water quality-based effluent limitations. Section 283.31 , Stats., provide authority to issue permits that require compliance with effluent limitations and standards for point source discharges to surface waters. General permits conveying coverage to multiple point sources can be issued pursuant to s. 283.35 , Stats. Section 283.45 , Stats., grants authority to develop permit factsheets to accompany the WPDES permit. The department also has general authority to promulgate rules under s. 227.11 (2) (a) , Stats., that interpret the specific statutory authority granted in ch. 283 , Stats.

4. Related Statutes or R ule s :

These rules relate directly to the WPDES permit program that regulates wastewater discharges. Chapters NR 106 and 212 , Wis. Adm. Code, relate to permit processing and permit issuance procedures. Chapter NR 205 , Wis. Adm. Code, contains general provisions applicable to the WPDES permit program. Chapters NR 106 and NR 205 , Wis. Adm. Code, are also being updated in rule packages WT-13-12, WT-12-12, and WT-31-10. The following board order complements updates made in these other rule packages.

5. Plain Language A nalysis:

The purpose of the proposed rule is to ensure that the state’s regulations relating to Wisconsin Pollution Discharge Elimination System (WPDES) permitting, total maximum daily load (TMDL) implementation, and TMDL development are consistent with federal regulations. On July 18, 2011, the Department received a letter from the En vironmental Protection Agency ( EPA) id entifying seventy five issues and potential inconsistencies with Wisconsin’s authority to administer its approved WPDES permit program. Modifications to NR 106, NR 205, and 212 are necessary to a ddress several issues identified in the EPA letter. Minor clarifications and corrections are also needed in these chapters.

Specifically, the proposed rule revisions perform six overall functions: modifies the procedures used to calculate water quality based effluent limitations for toxic substances, changes how effluent limitations for toxic substances are expressed and when they are included in WPDES permits, modifies the proce dure used for determining when whole effluent toxicity (WET) limitations are required in WPDES permits, creates a framework to develop and implement TMDLs, clarifies and modifies procedures for granting compliance schedules, and other modifications. T he proposed changes are briefly described below.

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 li mitations 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 limitation s in low stream flow condition s 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 :

• E stablish effluent limitations on internal waste streams ( Issue 2 – 40 CFR 122.45 (h) )

• I nclude mass limitation s in addition to concentration based effluent limitations ( Issue 2 – 40 CFR 122.44 (f) )

• E xpress 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 th e 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 d ischarges not subject to NR 210 (e.g. industri al 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 C FR 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 rul e package does not change the reasonable potential procedures in s. NR 106.05 , Wis. Adm. Code.

However, clarification was provided to explicate that a ny 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 issue s 10 and 74 of EPA’s July 18 th letter. T he 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 95 th 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 developmen t procedures and to clarify procedures use d to implement approved TMDLs in WPDES permits. Specifically, this rule provides general allocation procedures for TMDL s developed in the Great Lakes Basin as well as in other basins in the state , and provides procedures for deriving TMDL-based limitations, and publ ic 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 schedule s 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 w ere 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 da ta . 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 m inor clarifications and corrections are also recommended in the proposed revisions .

6. Summary of, and Comparison with, Existing or Proposed F ederal S tatutes and R egulation s :

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 reasonabl e 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 122.4 5 (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 122.4 5 (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 complian ce 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 the se 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 clarif y EPA’s role in reviewing variances, and also provides clarification on chloride and ammonia variance procedures.

7. Comparison with S imilar R ules in Adjacent S tates:

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 appea r 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 7 Q10 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 convert ing 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 structure d 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 th e 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 thi s 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 TMDL s 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 state s 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.

8. Summary of Factual Data and Analytical M ethodologies Used and How Any Related Findings Support the Regulatory Approach C hosen :

The methodology identified in this rule package is based on Clean Water Act and Great Lake Initiative requirements and on EPA guidance including the Technical Support Document for Water Quality-based Toxics Control (March 1991). PB91-127415.

9. Analysis and Supporting Documents Used to D etermine the E ffect on S m all B usiness or in P reparation of an Economic Impact R eport:

[insert after EIA].

1 0 . Effect on Small B usiness (initial regulatory flexibility analysis) :

[insert after EIA].

11 . A gency Contact P erson:

Amanda Minks

Department of Natural Resources

Bureau of Water Quality WQ/3

101 South Webster Street

P.O. Box 7921

Madison, WI 53707-7921

[e-mail]

608-264-9223

12 . Place where comments are to be submitted and deadline for submission:

Written comments may be submitted at the public hearings , by regular mail, fax or email to:

Amanda Minks

Department of Natural Resources

101 South Webster Street

P.O. Box 7921

Madison, WI 53707-7921

[e-mail]

Phone: [phone]

Fax: [phone]

Written comments may also be submitted to the Department using the Wisconsin Administrative Rules Internet Web site at http://adminrules.wisconsin.gov .

Hearing dates and the comment submission deadline are to be determined.

Section 1   NR 106.03 (1) is renumbered NR 106.03 (1 r ).

NR 106.03 (1 r ) "Bioaccumulative chemical of concern" or "BCC" means any substance that has the potential to cause adverse effects which, upon entering the surface waters, accumulates in aquatic organisms by a human health or wildlife bioaccumulation factor greater than 1000.

Section 2   NR 106.03 (1 g ) is created to read:

NR 106.03 (1 g ) "AMZ" means acute mixing zone concentration based on presence of a zone of initial dilution pursuant to NR 106.06 (3) (c).

Section 3   NR 106.03 (2m) is created to read:

NR 106.03 (2m) "Deficiency toxicity" means a condition where adverse effects occur to aquatic organisms because concentrations of common ions (e.g., sodium, calcium, magnesium, potassium, etc.) are too low.

Section 4   NR 106.03 (2m) note is created to read:

NR 106.03 (2m) note Changes in the concentration of ions in surrounding waters can cause organisms to expend too much energy trying to regulate the balance of water and dissolved materials in bodily fluids, and may result in death.

Section 5   NR 106.03 (5m ) is created to read:

NR 106.03 (5m) "IC50 " means the point estimate of the concentration of a toxic substance, wastewater effluent or other aqueous mixture that would cause a 50% reduction in a nonlethal biological measurement, such as reproduction or growth, of the exposed test organisms in a given time period.

Section 6   NR 106.03 (10 ) and (11) are repealed .

Section 7   NR 106.03 ( 13 ) is amended to read :

NR 106.03 (13) "TUa" or "toxic unit acute" means a value that is equal to 100 divided by the LC50 except as provided in s. NR 106.08( 6 )( d ) .

Section 8   NR 106.03 (1 3 m) is created to read :

NR 106.03 (1 3 m) "TU c " or "toxic unit chronic " means a value that is equal to 100 divided by the IC25 or the IC50 except as provided in s. NR 106.08( 6 )( d ) .

Section 9   NR 106.03 (14) is amended to read:

NR 106.03 ( 14 ) " Whole effluent toxicity " or " WET " means the aggregate toxic effect of an effluent as measured directly by a toxicity test .

Section 10   NR 106 .0 4 ( 3 m ) is created to read:

NR 106.0 4 (3m) Water quality based effluent limitations may be imposed on internal waste streams before mixing with other waste streams or cooling water streams in lieu of imposing limitations at the point of discharge when imposition of limitations at the point source discharge location is impracticable or infeasible. Monitoring requirements as specified in s. NR 106.07(1) shall also be applied to the internal waste streams in these instances.

Section 11   NR 106.0 5 (1 ) (c) is amended :

NR 106.05 (1) (c) If the department determines that a limitation based on an aquatic life acute or chronic secondary value should be established in a permit according to the provisions in this section, a permittee may request an alternative wet WET limit in accordance with s. NR 106.07 (7) .

Section 12   NR 106 .0 5 ( 8 ) is repealed and re created to read:

NR 106.05 (8) If representative discharge data are not available for a substance, water quality based effluent limitations may be included in a permit if, in the judgment of the department, water quality standards will be exceeded if the discharge of the substance is not limited.

Section 13   NR 106.05 (8 ) note is repealed .

Section 14   NR 106.06 ( 3 ) (b) is repealed and re created to read:

NR 106.06 (3) (b) (intro) To assure compliance with par. (a) , the department shall calculate the water quality based effluent limitation for a substance using the following procedures whenever the background concentration of the substance in the receiving water is less than the acute water quality criterion or secondary value :

1. A limitation shall be calculated using the following conservation of mass equation whenever sufficient site-specific data exist:

Limitation = (WQC) (Qs +(1−f)Qe) − (Qs − fQe) (Cs)

        Qe

Where:

Limitation = Calculated limitation based on the acute toxicity criterion or secondary acute value (in units of mass per unit of volume).

WQC = The acute toxicity criterion appropriate for the receiving water as specified in chs . NR 102 to 105 or the secondary acute value determined according to ch. NR 1 05 or as referenced in sub. (1)

Qs = Receiving water design flow (in units of volume per unit time) pursuant to sub. (bm)

Qe = Effluent flow (in units of volume per unit time) as specified in s. NR 106.06(4)(d)

f = Fraction of the effluent flow that is withdrawn from the receiving water, and

Cs = Background concentration of the substance (in units of mass per unit volume) as specified in s. NR 106.06(4)(e) .

[NOTE to LRB: this is the same equation found in NR 106.06 (4) (b) (1) and formatted the same.]

2. A limitation shall be calculated equal to the final acute value or secondary value as determined in s. NR 105.05 for the respective fish and aquatic life subcategory for which the receiving water is classified.

3. The department shall use the more restrictive calculated effluent limitation derived in subds. 1. and 2., as the water quality based effluent limitation . If the background concentration of the substance in the receiving water is greater than the acute water quality criterion or secondary value for the substance, then the procedure in sub. (6) shall be used to calculate the limitation.

Section 15   NR 106.06 (3) (bm) is created to read:

NR 106.06 (3) (bm) The value of Qs of the receiving water for calculating effluent limitations in par. (a) based upon the acute fish and aquatic life criteria or secondary values developed according to ch. NR 105 shall be determined on a case-by-case basis. In no case may the Qs exceed the average minimum 1-day flow which occurs once in 10 years (1-day Q10) or if the 1-day Q10 flow data is not available, 80% of the average minimum 7-day flow which occurs once in 10 years (7-day Q10).

Section 16   NR 106 .0 6 (3 ) (c) (intro), 4., and 5. are amended to read:

NR 106.06 (3) (c) (intro) Except as provided in par. (d) sub. (2) , water quality based effluent limitations as derived in par . (b) may exceed the final acute value or the secondary acute value within a zone of initial dilution provided that the acute toxicity criteria or secondary acute values are met within a short distance from the point of discharge. A zone of initial dilution shall only be approved if the discharger demonstrates to the department that mixing of the effluent with the receiving water in the zone of initial dilution is rapid and all the following conditions are met:

4. The acute toxicity criteria or secondary acute values must shall be met within 10% of the distance from the edge of the outfall structure to the edge of a mixing zone which may be determined in accordance with s . NR 102.05 (3) .

5. The acute toxicity criteria or secondary acute values shall be met within a distance of 50 times the discharge length scale in any direction. The discharge length scale is defined as the square root of the cross-sectional area of any discharge outlet. If a multiport diffuser is used, this requirement must shall be met for each port using the appropriate discharge length scale for that port.

Section 17   NR 106 .0 6 ( 3 ) (e) is created to read:

NR 106.06 (3) (e) The department shall use the methodology in ss. NR 106.07 (3) to (5) to express water quality based effluent limitations derived in this subsection as permit effluent limitations.

Section 18   NR 106.06 ( 4 ) (f) is created to read:

NR 106.06 ( 4 ) (f) The department shall use the methodology in ss. NR 106.07 (3) to (5) to express water quality based effluent limitations derived in this subsection as permit effluent limitations.

Section 19   NR 106.06 (7) is amended to read:

NR 106.06 (7) Effluent limitations may be established in a permit under this subsection based upon the acute and chronic aquatic life toxicity criteria expressed as dissolved concentrations which are determined using the procedures specified in ss. NR 105.05 (5) and 105.06 (8) . Effluent limitations for metals calculated in this section shall be expressed as total recoverable in a permit .

Section 20   NR 106.07 (1) (title) is created to read:

NR 106.07 (1) (title) Permit monitoring frequency .

Section 21   NR 106.07 (2) is repealed and recreated to read:

NR 106.07 (2) General . Except as provided in subs. (3) and (4), a chemical specific water quality based effluent limitation that is calculated under this chapter shall be expressed in the permit as both a concentration limitation and a mass limitation unless the pollutant cannot appropriately be expressed by mass or a mass limitation is infeasible because the mass of the pollutant cannot be related to a measure of operation. Water quality based mass limits for discharges of chlorine are not required in permits. The concentration limitation shall be expressed in units of mg/L or equivalent units. The mass limitation shall be expressed in units of kg/day or equivalent units. All of the following procedures shall be used when calculating mass limitations:

NR 106.07(2)(a) (a) For dischargers subject to ch. NR 210 , an acute toxicity based concentration limitation that is derived by the procedure in s. NR 106.06 shall be converted to a mass limitation by using the discharger's maximum effluent flow, expressed as a daily total flow, that is anticipated to occur for 24 continuous hours during the design life of the treatment facility.

NR 106.07(2)(b) (b) For all other dischargers not subject to ch. NR 210 , an acute toxicity based concentration limitation that is derived by the procedures in s. NR 106.06 shall be converted to a mass limitation by using the discharger's maximum effluent flow, expressed as a daily total flow, that has occurred for 24 continuous hours and represents normal operations. When calculating a mass limitation, the department may consider a projected increase in effluent flow that will occur when production is increased or modified, or another wastewater source, including stormwater, that is added to an existing wastewater treatment facility. This paragraph does not waive the requirements of ch. NR 207 .

NR 106.07(2)(c) (c) An aquatic life chronic, human health or wildlife-based concentration limitation that is determined by the procedures in s. NR 106.06 shall be converted to a mass limitation by using the same effluent flow rate that was used in s. NR 106(4)(d) to calculate the chronic toxicity concentration limitation.

NR 106.07(2)(d) (d) A chronic toxicity based mass limitation that is determined by the procedures in s. NR 106.11 shall be converted to a concentration limitation by using an effluent flow rate from s. NR 106.06(4)(d) .

Section 22   NR 106.07 (2) note is created to read:

NR 106.07 (2) N ote : An example of where a mass limitation is infeasible is water quality based mass limits for discharges of temperature. Therefore, temperature mass limitations are not required in permits.

Section 23   NR 106.07 (3) is repealed and recreated to read:

NR 106.07 (3) E xpression of concentration limitations in permits for continuous discharges subject to NR 210. (a) Applicability. The procedures for expressing limitations in permits in this subsection apply to continuous discharges subject to ch. NR 210 where there is reasonable potential under s. NR 106.05 to exceed a water quality based effluent limitation based on fish and aquatic life protection, human health or wildlife protection that is calculated pursuant to s. NR 106.06 . This subsection does not apply if another provision in this chapter or another administrative code requires a different time period for expressing limits for a specific pollutant , type of discharge or parameter , or if the department determines that expression of limitations in accordance with this subsection is impracticable pursuant to sub. (10) .

Note: An example of a different time period for expressing limits for a specific pollutant or parameter is WET limitations as specified in s. NR 106.09 .

(b) Expression of Water Quality Based Effluent Limitations based on Acute Criterion. I f there is reasonable potential pursuant to s. NR 106.05 to exceed a water quality based effluent limitation calculated under s. NR 106.06 f or a pollutant that is based on an acute criterion or secondary value , that limitation shall be expressed as a daily maximum and included in the WPDES permit.

(c) Expression of Water Quality Based Effluent Limitations based on Chronic Criterion. I f there is reasonable potential pursuant to s. NR 106.05 to exceed a water quality based effluent limitation calculated under s. NR 106.06 for a pollutant that is based on a chronic criterion or secondary value that limitation shall be expressed as a weekly average and included in the WPDES permit.

(d) Expression of Water Quality Based Effluent Limitations based on Human Health or Wildlife Criterion. If there is reasonable potential under s. NR 106.05 to exceed a water quality based effluent limitation calculated under s. NR 106.06 for a pollutant that is based on a human health or wildlife criterion or secondary value, that limitation shall be expressed as a monthly average and included in the WPDES permit.

(e) Additional Permit Limitations. B oth a w eekly average and mo nthly average permit limitation shall be included in a WPDES permit for a pollutant whenever any water quality based effluent limitation for that pollutant is determined necessary pursuant to s. NR 106.05 . A d aily maximum limitation shall be included in a WPDES permit in addition to the weekly average and monthly average limitation if the daily maximum limitation is determined necessary pursuant to par. (b). The department shall use all of the following procedures to include weekly average and monthly average limitations in WPDES permits:

1. If a daily maximum limitation is the only limitation determined necessary for a pollutant pursuant to s. NR 106.05 , a weekly average and monthly average limitation shall still be included in the permit and shall be set equal to the daily maximum limitation or the calculated weekly average and monthly average water quality based effluent limitations, which ever is more restrictive.

2. If a weekly average limitation is determined necessary for a pollu tant pursuant to s. NR 106.05 , but a monthly average limitation is not determined necessary for that pollutant in the permit pursuant to s. NR 106.05 , a monthly average limitation shall still be included in the permit and shall be set equal to the weekly average limitation or the monthly average water quality based effluent limitation calculated under s. NR 106.06 , which ever is more restrictive. A daily maximum limitation shall be included if deemed necessary pursuant to s. NR 106.05 .

3. If a daily maximum a nd monthly average limitation are determined necessary in a permit for a pollutant pursuant to s. NR 106.05 , but a weekly average limit is not necessary for that pollutant pursuant to s. NR 106.05 , a weekly average limitation shall still be included in the permit for the pollutant and shall be set equal to the daily maximum limitation or the weekly average water quality based effluent limitation calculated under s. NR 106.06 , whichever is more restrictive.

4. If a monthly average limitation is the only limitation determined to be necessary for a pollutant pursuant to s. NR 106.05 , a weekly average limitation shall still be included in the permit and shall be set equal to the weekly average water quality based effluent limitation calculated under s. NR 106.06 , or a weekly average limitation calculated using the following procedure, whichever is more restrictive :

Weekly Average Limitation = (Monthly Average Limitation* MF )

Where:

MF = Multiplication factor as defined in Table 1

CV= The coefficient of variation (CV) as calculated in s. NR 106.07(5m)

n= the number of samples per month required by WPDES permit

NR 106.07 (3) (e) (4) Table 1- Multiplication Factor

CV

n=1

n=2

n=3

n=4

n=8

n=12

n=16

n=20

n=24

n=30

0.1

1.07

1.13

1.14

1.16

1.18

1.20

1.20

1.21

1.21

1.22

0.2

1.14

1.25

1.29

1.33

1.39

1.42

1.43

1.45

1.45

1.46

0.3

1.22

1.37

1.45

1.50

1.60

1.65

1.68

1.70

1.72

1.74

0.4

1.30

1.50

1.60

1.67

1.82

1.89

1.94

1.97

2.00

2.02

0.5

1.38

1.622

1.75

1.84

2.04

2.14

2.20

2.25

2.28

2.32

0.6

1.46

1.73

1.89

2.01

2.25

2.38

2.46

2.52

2.57

2.62

0.7

1.54

1.84

2.02

2.16

2.45

2.61

2.72

2.79

2.85

2.91

0.8

1.61

1.94

2.14

2.29

2.64

2.83

2.95

3.04

3.11

3.19

0.9

1.69

2.03

2.25

2.41

2.81

3.03

3.17

3.28

3.36

3.45

1.0

1.76

2.11

2.34

2.52

2.96

3.20

3.37

3.49

3.59

3.70

1.1

1.83

2.18

2.43

2.62

3.09

3.36

3.55

3.69

3.80

3.93

1.2

1.90

2.25

2.50

2.70

3.20

3.50

3.71

3.86

3.99

4.13

1.3

1.97

2.31

2.57

2.77

3.30

3.62

3.85

4.02

4.15

4.31

1.4

2.03

2.37

2.63

2.83

3.39

3.73

3.97

4.15

4.30

4.47

1.5

2.09

2.42

2.68

2.89

3.46

3.82

4.08

4.27

4.43

4.62

1.6

2.15

2.42

2.73

2.89

3.46

3.89

4.16

4.37

4.54

4.62

1.7

2.21

2.52

2.77

2.98

3.57

3.96

4.24

4.46

4.64

4.85

1.8

2.27

2.56

2.81

3.01

3.61

4.01

4.30

4.53

4.72

4.94

1.9

2.32

2.60

2.84

3.05

3.65

4.05

4.35

4.59

4.79

5.02

2.0

2.37

2.64

2.87

3.07

3.67

4.09

4.40

4.64

4.84

5.09

5. Limitations calculated under subds. (1) to (4) shall be expressed in terms of concentration unless the department determines that a mass limitation is also necessary to protect fish and aquatic life, human health, or wildlife due to the variability of effluent flow or stream flow or other site-specific factors.

Section 24   NR 106.07 (3) note is created to read:

NR 106.07 (3) Note: This methodology is based on the Technical Support Document for Water Quality-based Toxics Control (March 1991). PB91-127415.

Section 25   NR 106.07 ( 4 ) is repealed and re created to read:

NR 106.07 (4). Expression of concentration limitations in permits for continuous discharges not subject to NR 210 . (a) Applicability. The procedures for expressing limitations in this subsection apply to continuous discharges that are not subject to ch. NR 210 and where there is reasonable potential under s. NR 106.05 to exceed a water quality based effluent limitation based on fish and aquatic life protection, human health or wildlife protection that is calculated pursuant to pursuant to s. NR 106.06 . This subsection does not apply if another provision in this chapter or another administrate code chapter requires a different time period for expressing limits that is specific to a pollutant , type of discharge or other parameter , or if the department determines that expression of limitations in accordance with this subsection is impracticable pursuant to sub. (10) .

Note: An example of a different time period for expressing limits for a specific pollutant or parameter is WET limitations as specified in s. NR 106.09 .

(b) Expression of Water Quality Based Effluent Limitations based on Acute Criterion. If there is reasonable potential pursuant to s. NR 106.05 to exceed a water quality based effluent limitation calculated under s. NR 106.06 for a pollutant that is based on an acute criterion or secondary value, that limitation shall be expressed as a daily maximum and included in the WPDES permit.

(c) Expression of Water Quality Based Effluent Limitations based on Chronic Criterion. If there is reasonable potential pursuant to s. NR 106.05 to exceed a water quality based effluent limitation calculated under s. NR 106.06 for a pollutant that is based on a chronic criterion or secondary value that limitation shall be expressed as a weekly average and included in the WPDES permit.

(d) Expression of Water Quality Based Effluent Limitations based on Human Health or Wildlife Criterion. If there is reasonable potential under s. NR 106.05 to exceed a water quality based effluent limitation calculated under s. NR 106.06 for a pollutant that is based on a human health or wildlife criterion or secondary value, that limitation shall be expressed as a monthly average and included in the WPDES permit.

(e) Additional Permit Limitations. Both a daily maximum and monthly average permit limitation shall be included in a WPDES permit for a pollutant whenever any water quality based effluent limitation for that pollutant is determined necessary pursuant to s. NR 106.05 . A w eekly average limitation shall be included in a WPDES permit in addition to daily maximum and monthly average limitation if the weekly average limit is determined necessary pursuant to par . (c). The department shall use all of the following procedures to include daily maximum and monthly average limitations in WPDES permits:

1. If a daily maximum limitation is the only limitation determined necessary for a pollutant pursuant to s. NR 106.05 , a monthly average limitation shall still be included in the permit and set equal to the daily maximum limitation or the monthly average water qu ality based effluent limitation calculated pursuant to s. NR 106.06 , whichever is more restrictive.

2. If a weekly average limitation is the only limitation determined necessary for a pollutant pursuant to s. NR 106.05 a monthly average limitation shall still be included in the permit and shall be set equal to the weekly average limitation or the monthly average water quality based effluent limitation calculated pursuant to s. NR 106.06 , whichever is more restrictive. A daily maximum limitation shall also be included in the WPDES permit and set equal to the daily maximum water quality based effluent limitation calculated pursuant to s. NR 106.06 or a daily maximum limitation calculated using the following procedure, whichever is more restrictive:

Daily Maximum Limitation= WQBELc * D MF

Where:

WQBELc = water quality based effluent limitation calculated based on chronic criteria pursuant to s. NR 106.06 .

DMF= Daily Multiplication Factor as defined in Table 2, where

CV= The coefficient of variation (CV) as calculated in s. NR 106.07(5m)

NR 106.07 (4) (e) (2) Table 2- Daily Multiplication Factor

CV	Multiplying Factor

0.1

1.114

0.2

1.235

0.3

1.359

0.4

1.460

0.5

1.557

0.6

1.639

0.7

1.712

0.8

1.764

0.9

1.802

1.0

1.828

1.1

1.842

1.2

1.849

1.3

1.851

1.4

1.843

1.5

1.830

1.6

1.815

1.7

1.801

1.8

1.781

1.9

1.751

2.0

1.744

3. If a monthly average limitation is determined necessary , but a daily maximum limitation is not determined necessary for that pollutant pursuant to s. NR 106.05 , a daily maximum limitation shall still be included in the permit and shall be set equal to the daily maximum water quality based effluent limitation calculated pursuant to s. NR 106.06 or a daily maximum limitation calculated using the following procedure, whichever is more restrictive:

Daily Maximum Limitation = (Monthly Average Limitation* MF )

Where:

Multiplication Factor = Multiplication Factor as defined in s. NR 106.07 (3) (e) 4 Table 1 , where

CV= The coefficient of variation (CV) as calculated in s. NR 106.07 (5m)

n= the number of samples per month required by WPDES permit

4. Limitations calculated under subds. (1) to (3) shall be expressed in terms of concentration unless the department determines that a mass limitation is also necessary to protect fish and aquatic life, human health, or wildlife due to the variability of effluent flow or stream flow or other site-specific factors.

Section 26   NR 106.07 (4) note is created to read:

NR 106.07 (4) Note: This methodology is based on the Technical Support Document for Water Quality-based Toxics Control (March 1991). PB91-127415.

Section 27   NR 106.07 (5) is repealed and re created to read:

  NR 106.0 7 (5) Expression of concentration limitations in permits for noncontinuous discharges. (a) Applicability. The procedures for expressing limitations in this subsection apply to seasonal discharges, discharges proportional to stream flow, or other unusual discharge situations that do not meet the definition of a continuous discharge pursuant to s. NR 205.03 (9g) where there is reasonable potential under s. NR 106.05 to exceed a water quality based effluent limitation based on fish and aquatic life protection, human health or wildlife protection. Water quality based effluent limitations shall be calculated pursuant to s. NR 106.06 .

(b) Acute Reasonable Potential . Pursuant to s. NR 106.05 , if there is reasonable potential to exceed a water quality based effluent limitation for a pollutant that is based on an acute criterion or secondary value then the acute concentration limitation calculated under s. NR 106.06 shall be expressed as a daily maximum and included in the permit .

(c) Chronic and Human Health or Wildlife Reasonable Potential . Pursuant to s. NR 106.05 , if there is reasonable potential to exceed a water quality based effluent limitation for a pollutant based on a chronic, a h uman h ealth or w ildlife criterion or secondary value , limitations shall be included in the permit and expressed on a case-by-case basis. The Department shall consider the following factors:

1. Frequency and duration of discharge

2. Total mass of discharge

3. Maximum flow rate of discharge

4. Whether the pollutant is subject to a technology based limitation or other limitation expressed by mass, concentration, or other appropriate measure in the WPDES permit .

Section 28   NR 106.07 ( 5m ) and (title) are created to read:

NR 106.07 (5m) Coefficient of variation. (a) T he coefficient of variation (CV) shall be calculated as the ratio of the standard deviation of the representative effluent data divided by the arithmetic average of the representative effluent data, except as provided in par. (b ).

(b) If there are fewer than ten representative data points the CV shall be set equal to 0.6.

(c) When calculating the CV in par. (a) a monitoring result less than the limit of detection may be assigned a value of zero. If the effluent limitation is less than the limit of detection, the department may substitute a value other than zero for results less than the limit of detection, after considering the number of monitoring results that are greater than the limit of detection and if warranted when applying appropriate statistical techniques.

Section 29   NR 106.07 (6 ) (title) is created to read:

NR 106.07 (6) (title) Monitoring and compliance with limitations below the level of detection .

Section 30   NR 106.07 (7 ) (title) is created to read:

NR 106.07 (7) (title) Whole effluent toxicity a s alternative limit .

Section 31   NR 106.07 (8) (title) is created to read:

NR 106.07 (8) (title) S e condary v alues and s tudies within the great lakes basin.

Section 32   NR 106.07 ( 8 ) is amended to read:

NR 106.07 (8) If the effluent limitation based on a secondary value is established in a permit, the permittee permittees discharging to the Great Lakes basin may request that additional time be added to the compliance schedule, according to s. NR 106.117 (2) , for the permittee to conduct studies, other than studies for site-specific criteria pursuant to s. NR 105.02 (1) , that are needed to propose a revision to the secondary value upon which the effluent limitation is based. During this time, the permittee may provide additional data necessary to either refine the secondary value or calculate a water quality criterion.

Section 33   NR 106.07 (9 ) (title) is create to read:

NR 106.07 (9) (title) Wet weather mass limitations.

Section 34   NR 106.07 (1 0 ) and (title) is created to read:

NR 106.07 (1 0 ) (title) Alternative methods for limit expression. The department may use an alternative method from the methodology specified in subs. (3) through ( 5) to express water quality based effluent limitations in WPDES permits if the department determine s that the methods in subs. (3)-(5) are impracticable and an alternative methodology is necessary and appropriate and adequately protective of the designated uses of the receiving and downstream waters as specified in ch. NR 102 .

Section 35   NR 106.08 is repealed and recreated to read:

NR 106.08 (1) General . T he department shall establish whole effluent toxicity testing requirements and limitations whenever necessary to meet applicable water quality standards as specified in chs. NR 102 to 105 as measured by exposure of aquatic organisms to an effluent and specified effluent dilutions. When considering the necessity for whole effluent toxicity testing requirements and limitations, the department shall consider in-stream biosurvey data and data from ambient toxicity analyses, whenever such data are available.

(2)   Determination of necessity. If representative discharge data are available for an effluent being discharged from a point source, whole effluent toxicity testing requirements are necessary when:

(a) Existing aquatic life toxicity test data generated according to standard test protocols indicate a potential for an effluent from a point source discharge to adversely impact the receiving water aquatic life community.

(b) A water quality based effluent limitation for a toxic substance is determined necessary in s. NR 106.05 .

(3) Representative data. Toxicity test data available to the department shall be considered representative when those data meet the following conditions:

(a) Data are representative of normal discharge conditions and current effluent quality;

(b) Data were produced by a lab certified or registered under ch. NR 149 ;

(c) Data were produced from toxicity test procedures specified in the WPDES permit; and

(d) Data were produced from toxicity tests that met all applicable quality assurance/quality control requirements specified in the WPDES permit.

( 4 )   No representative data. If no representative discharge data are available for an effluent being discharged from a point source, whole effluent toxicity testing requirements are necessary if, in the judgment of the department, water quality standards may be exceeded. In such cases, all of the follow ing factors shall be considered:

(a) Any relevant information which is available that indicates a potential for an effluent to impact the receiving water aquatic life community.

(b) Available dilution in the receiving water.

(c) Discharge category and predicted effluent quality.

(d) Proximity to other point source dischargers.

( 5 )   Other considerations. Regardless of the results of the analysis conducted under this section, the department may, whenever determined necessary, require whole effluent toxicity testing for a point source discharge. The department may use information submitted under s. 323.60 (5) (c) and (d) , Stats., together with other information, in determining when whole effluent toxicity testing is necessary.

( 6 )   Reasonable potential to receive an acute or chronic whole effluent toxicity limit. (a) General. Whole effluent toxicity limits are established in a permit according to s. NR 106.09 whenever representative, facility-specific whole effluent toxicity data demonstrate that the effluent is or may be discharged at a level that will cause, have the potential to cause, or contribute to an excursion of a water quality standard. Whole effluent toxicity limits may also be imposed in the absence of facility-specific whole effluent toxicity test data, on a case-by-case basis, whenever facility-specific or site-specific data or conditions indicate toxicity to aquatic life that is attributable to the discharger.

(b) Reasonable potential.

1. If a zone of initial dilution has not been approved by the department, the potential to exceed an acute criterion shall be calculated using the following equation:

(TUa effluent) (B) > 1.0

Where:

TUa effluent= maximum calculated TUa from the most sensitive species in the data set

B= Reasonable potential multiplication factor determined under par . ( c )

1.0= Numeric acute WET limitation in acute toxic units (TUa) derived from narrative criterion in s. NR 102.04(1)(d)

2. If a zone of initial dilution has been approved by the department, the potential to exceed an acute criterion shall be calculated using the following equation:

[ ( TUa effluent) (B) (AMZ)] > 1.0

Where:

TUa effluent= Maximum calculated TUa from the most sensitive species in the data set

B= Reasonable potential multiplication factor determined under par . ( c )

AMZ= Acute mixing zone concentration based on presence of a zone of initial dilution as defined in s. NR 106.03(1) expressed as a decimal

1.0= Numeric acute WET limitation in acute toxic units (TUa) derived from narrative criterion in s. NR 102.04(1)(d)

3. The potential to exceed a chronic criterion shall be calculated using the following equation:

[ (TUc effluen t) (B) (IWC)] > 1.0

Where:

TUc effluent= Maximum calculated TUc from the most sensitive species in the data set

B= Reasonable potential multiplication factor determined under par. ( c )

IWC= Instream waste concentration as defined in s. NR 106.03(6) expressed as a decimal

1.0= Numeric chronic WET limitation in chronic toxic units (TUc) derived from narrative criterion in s. NR 102.04(4)(d)

( c ) Reasonable potential multiplication factor . The reasonable potential multiplication factor in par. (b) is used to convert the calculated effluent toxicity value to the estimated 95 th percentile toxicity value. The department shall use all of the following methods to select a reasonable potential multiplication factor:

1. Where there are less than 10 individual toxicity detects, the mu ltiplication factor shall be taken from Table 4 and based on a coefficient of variation of 0.6.

2. Where there are 10 or more individual toxicity detects, the mu ltiplication factor shall be taken from Table 4 and based on coefficient of variation calculated as the standard deviation of the WET test endpoints (IC25, IC50 or LC50) divided by the arithmetic mean of the WET tests.

NR 106.08 (5) ( c ) Table 4 — Reasonable Potential Multiplication Factor.

Coefficient of variation (CV)

Number of samples (n)

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

1.1

1.2

1.3

1.4

1.5

1.6

1.7

1.8

1.9

2.0

1

-

-

-

-

-

6.2

-

-

-

-

-

-

-

-

-

-

-

-

-

2

-

-

-

-

-

3.8

-

-

-

-

-

-

-

-

-

-

-

-

-

3

-

-

-

-

-

3.0

-

-

-

-

-

-

-

-

-

-

-

-

-

4

-

-

-

-

-

2.6

-

-

-

-

-

-

-

-

-

-

-

-

-

5

-

-

-

-

-

2.3

-

-

-

-

-

-

-

-

-

-

-

-

-

6

-

-

-

-

-

2.1

-

-

-

-

-

-

-

-

-

-

-

-

-

7

-

-

-

-

-

2.0

-

-

-

-

-

-

-

-

-

-

-

-

-

8

-

-

-

-

-

1.9

-

-

-

-

-

-

-

-

-

-

-

-

-

9

-

-

-

-

-

1.8

-

-

-

-

-

-

-

-

-

-

-

-

-

10

1.1

1.2

1.3

1.5

1.6

1.7

1.9

2.0

2.2

2.3

2.4

2.6

2.7

2.8

3.0

3.1

3.2

3.3

3.4

3.6

11

1.1

1.2

1.3

1.4

1.6

1.7

1.8

1.9

2.1

2.2

2.3

2.4

2.5

2.7

2.8

2.9

3.0

3.1

3.2

3.3

12

1.1

1.2

1.3

1.4

1.5

1.6

1.7

1.9

2.0

2.1

2.2

2.3

2.4

2.5

2.6

2.7

2.8

2.9

3.0

3.0

13

1.1

1.2

1.3

1.4

1.5

1.6

1.7

1.8

1.9

2.0

2.1

2.2

2.3

2.4

2.5

2.5

2.6

2.7

2.8

2.9

14

1.1

1.2

1.3

1.4

1.4

1.5

1.6

1.7

1.8

1.9

2.0

2.1

2.2

2.3

2.3

2.4

2.5

2.6

2.6

2.7

15

1.1

1.2

1.2

1.3

1.4

1.5

1.6

1.7

1.8

1.8

1.9

2.0

2.1

2.2

2.2

2.3

2.4

2.4

2.5

2.5

16

1.1

1.1

1.2

1.3

1.4

1.5

1.6

1.6

1.7

1.8

1.9

1.9

2.0

2.1

2.1

2.2

2.3

2.3

2.4

2.4

17

1.1

1.1

1.2

1.3

1.4

1.4

1.5

1.6

1.7

1.7

1.8

1.9

1.9

2.0

2.0

2.1

2.2

2.2

2.3

2.3

18

1.1

1.1

1.2

1.3

1.3

1.4

1.5

1.6

1.6

1.7

1.7

1.8

1.9

1.9

2.0

2.0

2.1

2.1

2.2

2.2

19

1.1

1.1

1.2

1.3

1.3

1.4

1.5

1.5

1.6

1.6

1.7

1.8

1.8

1.9

1.9

2.0

2.0

2.0

2.1

2.1

20

1.1

1.1

1.2

1.2

1.3

1.4

1.4

1.5

1.5

1.6

1.6

1.7

1.7

1.8

1.8

1.9

1.9

2.0

2.0

2.0

30

1.0

1.1

1.1

1.1

1.2

1.2

1.2

1.3

1.3

1.3

1.3

1.4

1.4

1.4

1.4

1.5

1.5

1.5

1.5

1.5

40

1.0

1.0

1.1

1.1

1.1

1.1

1.1

1.1

1.2

1.2

1.2

1.2

1.2

1.2

1.2

1.2

1.2

1.2

1.3

1.3

50

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.1

1.1

1.1

1.1

1.1

1.1

1.1

1.1

1.1

1.1

1.1

1.1

1.1

60

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

1.0

70

1.0

1.0

1.0

1.0

1.0

0.9

0.9

0.9

0.9

0.9

0.9

0.9

0.9

0.9

0.9

0.9

0.9

0.9

0.9

0.9

80

1.0

1.0

1.0

0.9

0.9

0.9

0.9

0.9

0.9

0.9

0.9

0.9

0.9

0.9

0.8

0.8

0.8

0.8

0.8

0.8

90

1.0

1.0

0.9

0.9

0.9

0.9

0.9

0.9

0.9

0.8

0.8

0.8

0.8

0.8

0.8

0.8

0.8

0.8

0.8

0.8

100

1.0

1.0

0.9

0.9

0.9

0.9

0.9

0.8

0.8

0.8

0.8

0.8

0.8

0.8

0.8

0.8

0.8

0.7

0.7

0.7

(d) Maximum toxicity values. The Department shall set the TUc effluent and TUa effluent values in par . (b) equal to zero whenever toxicity is not-detected or the LC50, IC25, or IC50 equals or exceeds 100% effluent.

(7) Data Exclusions. The Department may exclude data from a WET reasonable potential determination when those data meet any of the following conditions:

(a) Data are not representative pursuant to sub . ( 3 );

(b) Positive WET results are caused by deficiency toxicity only; or

(c) Positive WET results are caused by groundwater or surface water remediation needed to correct or prevent an existing surface or groundwater contamination situation or a public health problem.

Section 36   NR 106.0 9 (2) ( e ) is repealed and re created to read:

NR 106.09 (2) (e) Acute whole effluent toxicity limits shall be expressed as 1.0 TU a unless an AMZ is approved in which case these limits shall be expressed as a value that is 100 divided by the AMZ. Compliance with an acute whole effluent toxicity water quality based limitation shall be determined by comparing the TU a endpoint from each toxicity test to the limitation. Pursuant to s. NR 106.08(6)(d) a calculated LC 50 that exceeds 100% is set equal to zero.

Section 37   NR 106.09 (2) ( f ) is created to read:

NR 106.09 (2 ) (f) Whole effluent acute toxicity limitations shall be expressed in permits as daily maximum limitations.

Section 38   NR 106.09 (3) (b) is amended to read:

NR 106.09 (3) (b) To assure compliance with par. (a), an effluent, after dilution with an appropriate allowable quantity of receiving water flow equivalent to that provided by receiving water flows specified in s. NR 106.06(4)(c) NR 106.06(3)(c) or implied in s. NR 106.06(4)(b)2. NR 106.06(3)(b)2. , may not cause a significant adverse effect, as determined by subds. 1. and 2. , to a test organism population when compared to an appropriate control.

Section 39   NR 106.09 (3 ) (b) 1. is amended to read:

NR 106.09 (3) (b) 1. Using statistical interpretation methods appropriate to the toxicity test protocol, an adverse effect will be determined to be significant if the statistically derived IC25 or IC50, as specified for each species in the whole effluent toxicity test methods required in s. NR 219.0 4 , Table A, from the whole effluent toxicity test, is less than the calculated IWC.

Section 40   NR 106.09 ( 3 ) (c) is repealed and recreated to read:

NR 106.09 (3) (c) Chronic whole effluent toxicity limits shall be expressed as a value that is 100 divided by the IWC. Compliance with a chronic whole effluent toxicity water quality based limitation shall be determined by comparing the monthly average calculated TUc from all toxicity tests conducted during that month to the limitation. Pursuant to s. NR 106.08(6)(d) a calculated IC 25 or IC 50 that exceeds 100% is set equal to zero.

Section 41   NR 106.09 (3) (d) is created to read:

NR 106.09 (3) (d) Whole effluent chronic toxicity limitations shall be expressed in permits as monthly average limitations.

Section 42   NR 106.11 (note) is created to read:

NR 106.07 Note NR 106.11 Note: The method of allocating the combined allowable load in to s. NR 106.11 does not have to be based on the effluent flow rates specified in s. NR 106.04(4)(d) .

Section 43   NR 106.115 Table 1 (title) and Table 2 (title) are amended to read:

NR 106.115 Table 1 – Toxicity Equivalency Factor for CDDs and CDFs

NR 106.115 Table 2 – Bioaccumulation Equivalency Factor for CDDs and CDFs

[NOTE to LRB: title formatting change requested for consistency throughout tables in NR 106]

Section 44   NR 106.145 (9) (b ) note is repealed .

Section 45   NR 106.32 (2 ) (b) and 2. are amended to read:

NR 106.32 (2) (b) To assure compliance with par. (a) and except as provided in par . (c) and (e), water quality based effluent limitations for ammonia shall equal the final acute value as determined in s. NR 105.05 for the respective fish and aquatic life subcategory for which the receiving water is classified. The water quality based limitations based on acute toxicity shall be established as follows using all of the following methods :

NR 106.32 (2) (b) 2. If the permittee can demonstrate to the department through site specific information that the fish present in the receiving water are limited to those included in CW Category 2, CW Category 3 or CW Category 5, as described in ch. NR 105 , Table 2C, then effluent limitations shall be established based on the criteria shown in ch. NR 105 Table 2C for the respective CW Category. If the permittee intends to make a site-specific demonstration, the permittee shall notify the department prior to the end of the public comment period for permit reissuance. An additional period of time, not to exceed 6 months, shall be provided in the schedule of compliance under s. NR 106.37 to perform the demonstration. If the department grants approval for an alternative limitation based on CW Category 2, 3 or 5, the department shall propose a modification to the permit that includes include the alternative limit in a modified or reissued permit provided antidegradation requirements in chapter NR 207 have been satisfied.

Section 46   NR 106.32 (2) (b) (2) note is repealed.

Section 47   NR 106.32 (2) (e ) is created to read:

NR 106.32 (2) (e) To assure compliance with par . (a) , the department may calculate acute water quality-based effluent limitations using the following procedure if the department concludes that limitations calculated in par. (b) or (c) are not sufficiently protective of fish and aquatic life. The department may include the calculated WQBEL in a WPDES permit if this limitation is more stringent than the limitation calculated in par. (b) or (c):

Limitation = (WQC) (Qs +(1−f)Qe) − (Qs − fQe) (Cs)

        Qe

Where:

WQC = The acute ammonia toxicity criterion appropriate for the receiving water as specified in ch. NR 105 and par. (d) .

Qs = Receiving water design flow (in units of volume per unit time) as defined in NR 106.06(3)(bm)

Qe = Effluent flow (in units of volume per unit time) as specified in s. NR 106.06(4)(d) .

f = Fraction of the effluent flow that is withdrawn from the receiving water, and

Cs = Background concentration of the substance (in units of mass per unit volume) as specified in s. NR 106.06(4)(e) .

[NOTE to LRB: this is the same equation found in NR 106.06 (4) (b) (1) and formatted the same.]

Section 48   NR 106.32 (3 ) (a) 4. a. is amended to read :

NR 106.32 (3) (a) 4. a. Whenever the department determines that early life stage present ammonia criteria are applicable under this subdivision, the permittee may make a demonstration that the early life stages of burbot are not present at the discharge location and will not be affected by the discharge during the months of January and February. If the permittee intends to perform the demonstration, the permittee shall notify the department prior to the end of the public comment period for permit reissuance. The department shall allow an extended compliance schedule in the permit not to exceed one year for the permittee to provide the demonstration. If the department grants approval for an alternative limitation based on results of this study, the department shall include the alternative limit ation in a permit modification or reissuance provided antidegradation requirements in chapter NR 207 have been satisfied.

Section 49   NR 106.32 (3) (a) 4. a. note is repealed:

NR 106.32 (3) (a) 4. a. Note: On July 11, 2014, in Case No. Case No. 12CV3654, Midwest Environmental Defense Center Inc. v. Wisconsin Department of Natural Resources, et. al., an action for declaratory judgment under s. 227.40 , Stats., the Circuit Court for Dane County, Branch 1, entered a Final Order and Judgment providing in relevant part:

NR 106.32 Note That portion of Wis. Admin. Code § 106.32(3)(a)4. a which reads, "The department shall allow an extended compliance schedule in the permit not to exceed one year for the permittee to provide the demonstration." is declared invalid.

Section 50   NR 106.33 is repealed and recreated to read:

NR 106.33 (title) Determination of the necessity for and expression of water quality based effluent limits for ammonia.

  NR 106.33 (1) Reasonable potential. (a) For a permitted discharge that is not already subject to an ammonia water quality based effluent limitation, t he procedures specified in s. NR 106.05 shall be used to determine if water quality based effluent limitations for ammonia are necessary in a reissued permit. When application of the procedures in s. NR 106.05 results in a determination that ammonia effluent limits are not necessary in a permit, the wastewater treatment plant shall continue to be operated in a manner that optimizes the removal of ammonia within the design capabilities of the wastewater treatment plant. The department may require that the permittee monitor ammonia at a frequency established on a case-by-case basis in its discharge permit for the purpose of determining representative discharge levels.

(b) If a permittee has an ammonia limitation in an existing permit, the limitation shall continue to be included in any reissued permit. For new sources or new discharges, ammonia limitations shall be included in the permit if the permitted facility will be providing treatment for ammonia discharges.

( 2 ) Permit limitations for continuous POTWs. The procedures for expressing limitations in permits in this subsection apply to continuous discharges subject to ch. NR 210 where there is reasonable potential under s. NR 106.05 to exceed an ammonia limitation. Both a weekly average and monthly average permit limitations shall be included in a WPDES permit for ammonia whenever any water quality based effluent limitation for ammonia is determined necessary pursuant to sub. (1). A daily maximum limitation shall be included in WPDES permits in addition to weekly average and monthly average limitation if necessary pursuant to sub. (1). The department shall use all of the following procedures to include weekly average and monthly average limitations in WPDES permits:

(a) If a daily maximum limitation is the only ammonia limitation determined necessary pursuant to sub. (1) , w eekly average limitations shall be set equal to the WQBEL based on the 4-day chronic toxicity criteria calculated according to s. NR 106.32(3) or the daily maximum limitation, whichever is more restrictive .

(b) If a weekly average ammonia limitation is determined necessary pursua nt to sub. (1), and a monthly average limitation is not already determined necessary, m onthly average limitations shall be set equal to the WQBEL based on the 30-day chronic toxicity criteria calculated according to s. NR 106.32(3) or the weekly average limitation, whichever is more restrictive , except as provided in par. (c) .

(c) The department may on a case-by-case basis use an alternative methodology for calculating monthly average limitations whenever historical flow data or real time data are used to calculate weekly average limitations pursuant to s. NR 106.32(3)(c) 2 and these limitations are determined to be necessary pursuant to sub . (1).

(d) If a monthly average limitation is the only ammonia limitation determined to be necessary pursuant to sub. (1) , weekly average limitations shall be set equal to the WQBEL based on the 4-day chronic toxicity criteria calculated according to s. NR 106.32(3) or a weekly average limitation calculated using the following procedure, whichever is more restrictive:

Weekly Average Limitation = (Monthly Average Limitation* MF )

Where:

MF = Multiplication factor as defined in NR 106.07 (3) (e) (4) Table 1 , where

CV= The coefficient of variation (CV) as calculated in s. NR 106.07(5m)

n= the number of samples per month required by WPDES permit

(3) Permit limitations for other continuous discharges. The procedures for expressing limitations in this subsection apply to continuous discharges that are not subject to ch. NR 210 and where there is reasonable potential under s. NR 106.05 to exceed an ammonia limitation. Both a daily maximum and monthly average permit limitation shall be included in a WPDES permit for ammonia whenever any water quality based effluent limitation for ammonia is determined necessary pursuant to s. NR 106.05 . A weekly average limitations shall be included in WPDES permits in addition to daily maximum and monthly average limitation if necessary pursuant to sub. (1). The department shall use all of the following procedures to include daily maximum and monthly average limitations in WPDES permits:

(a) If a weekly average limitation is the only ammonia limitation determined necessary pursuant to sub. (1), a monthly average limitation shall be set equal to the WQBEL based on the 30-day chronic toxicity criteria or the weekly average limitation, whichever is more restrictive except as provided in par. (c) . A daily maximum limitation shall also be included in the WPDES permit and set equal to the daily maximum ammonia WQBEL pursuant to NR 106.32(2) or a daily maximum limitation calculated using the following procedure, whichever is more restrictive:

Daily Maximum Limitation= Weekly Average Limitation * D MF

Where:

D MF= Daily Multiplication Factor as defined in NR 106.07 (4) (e) (2) Table 2 , where

CV= The coefficient of variation (CV) as calculated in s. NR 106.07(5m)

(b) If a daily maximum ammonia limitation is determined necessary pursuant to sub. (1), and a monthly average limitation is not already determined necessary, m onthly average limitations shall be set equal to the WQBEL based on the 30-day chronic toxicity criteria calculated according to s. NR 106.32(3) or the daily maximum limitation, whichever is more restrictive except as provided in sub. (c) .

(c) The department may on a case-by-case basis use an alternative methodology for calculating daily maximum or monthly average limitations whenever historical flow data or real time data are used to calculate weekly average limitations pursuant to s. NR 106.32(3)(c) 2 and these limitations are determined to be necessary pursuant to sub . (1).

(d) If a monthly average limitation is determined necessary and a daily maximum limitation is not already determined necessary pursuant to s ub. (1) , a daily maximum limitation shall be set equal to the daily maximum ammonia WQBEL pursuant to NR 106.32(2) or a daily maximum limitation calculated using the following procedure, whichever is more restrictive:

Daily Maximum Limitation = (Monthly Average Limitation* MF )

Where:

MF= Multiplication factor as defined in s. NR 106.07 (3) (e) 4 Table 1 , where

CV= The coefficient of variation (CV) as calculated in s. NR 106.07 (5m)

n= the number of samples per month required by WPDES permit

(4) Permit limitations for noncontinuous discharges. (a) . The department shall include ammonia water quality based effluent permit limitations in WPDES permits for seasonal discharges, discharges proportional to stream flow, or other unusual discharge situations that do not meet the definition of a continuous discharge whenever ammonia water quality based effluent limitations are deter mined necessary pursuant to sub. (1). Ammonia limitations shall be expressed in accordance with s. NR 106.32(5) unless the department determines on a case-by-case basis that an alternative averaging period is appropriate. The Department shall consider all of the following when making a case-by-case determination:

(a) Frequency and duration of discharge

(b) Total mass of discharge

(c) Maximum flow rate of discharge

(d) Whether ammonia is subject to a technology based limitation or other limitation expressed by mass, concentration, or other appropriate measure in the WPDES permit.

Section 51   NR 106.34 is repealed .

Section 52   NR 106.36 (3) Table 1 (title) is amended to read:

NR 106.36 (3) Table 1 - Ammonia Multiplier

[NOTE to LRB: title formatting change requested for consistency throughout tables in NR 106]

Section 53   NR 106.36 (3) n ote is repealed .

Section 54   NR 106.36 (4 ) is repealed .

Section 55   NR 106.37 (1 ) is amended to read:

NR 106.37 ( 1 ) The department shall determine and specify a reasonable compliance schedule in the WPDES permit if the permittee is unable to meet the ammonia effluent limits determined according to this subchapter at the time of permit reissuance. The department shall establish the term of the compliance schedule on a case-by-case basis and shall consider consistent with the requirements in s. NR 106.117 . When establishing a compliance schedule, the department shall consider factors such as necessary planning, complexity of wastewater treatment issues, scope of construction, equipment delivery time, and construction seasons in establishing a schedule. In no circumstance may the date of compliance with the limits extend more than 5 years after the date of permit reissuance , unless a variance has been granted pursuant to s. NR 106.38 .

Section 56   NR 106.37 (1) note is repealed .

Section 57   NR 106.37 (2 ) is repealed and re created to read:

NR 106.37 ( 2 ) If the department modifies or the permit to adjust ammonia limitations based on an approval of demonstrations made pursuant to either ss. NR 106.32(2)(b)2 . or 106.32(3)(a)4a. ,the department may adjust the compliance schedule if necessary and appropriate.

Section 58   NR 106.37 (2) note is repealed.

Section 59   NR 106.37 (3 ) and NR 106.37 ( 3) note are repealed .

Section 60   NR 106.38 is repealed .

Section 61   NR 106.55 (6) (a) Table 1 (title) is amended to read:

NR 106.55 (6) (a) Table 1 – Flow Ratio Categories

[NOTE to LRB: title formatting change requested for consistency throughout tables in NR 106]

Section 62   NR 106.62 is amended to read:

NR 106.62. Compliance schedules. Compliance with the effluent limitations shall be attained as soon as reasonably possible, but no later than the expiration date of the permit. When a permit is issued or reissued with effluent temperature limitations established using the procedures in this subchapter and representative effluent temperature data are available at the time of permit issuance or reissuance, the permit may contain a compliance schedule consistent with the provisions in NR 106.117 when either of the following conditions is met:

NR 106.62(1) (1)   The permittee does not apply for an alternative effluent limitation under the provisions of subch. VI.

NR 106.62(2) (2)   The permittee applies for an alternative effluent limitation under the provisions of subch. VI and, after reviewing the data and information provided with the application, the department determines that sufficient information to establish alternative effluent limitations for temperature is not available.

Section 63   NR 106.75 is amended to read:

NR 106.75 Whenever the department issues or modifies a permit with alternative effluent limitations for temperature established using the procedures in this subchapter, the permit may contain a compliance schedule consistent with the provisions in NR 106.117 to attain such limitations. Compliance with the limitations shall be attained as soon as reasonably possible, but no later than the expiration date of the permit.

Section 64   NR 106.83 (2 ) (c) is amended to read:

NR 106.83 ( 2 ) (c) Department determinations. The department shall review the application submitted by the permittee. The application shall be approved if the department agrees with the permittee's basis for concluding that the findings in sub. (2) (a) for a chloride variance are applicable to its discharge. The department shall obtain US EPA approval before a variance is included in a WPDES permit pursuant to sub. (2) .

Section 65   NR 106.87 (1 ) is amended to read:

NR 106.87 ( 1 ) calculated limitations . If water quality-based effluent limitations for chloride are deemed necessary, those limitations shall be derived pursuant to s. ss. NR 106.06 and NR 106.07 , and for the purposes of this subchapter, shall be labeled "calculated limitations".

Section 66   NR 106.88 (1 ) is repealed and re created to read:

NR 106.88 ( 1 ) Chloride limitations in permits . If chloride water quality-based effluent limitations are deemed to be necessary in accordance with s. NR 106.85 , the department shall use all of the following procedures to include the calculated limitations in the permit with an appropriate compliance schedule as necessary and appropriate :

(a) Effluent limitations based on an acute criterion shall be expressed in permits as daily maximum limitations; and effluent limitations based on a chronic criterion shall be expressed in permits as weekly average limitations.

(b) T he department shall include limitations in a WPDES permit consistent with the protocols in s s . NR 106.07 (3) to (5) .

(c) Mass limitations calculated pursuant to s s . NR 106.07 (2) and (9) shall also be included in the WPDES permit in addition to concentration based effluent limitations whenever water quality-based effluent limitations are determined to be necessary.

(d) Any compliance schedule for a water quality based effluent for chloride shall be consistent with the requirements in s. NR 106.117 .

Section 67   NR 106.88 (2) note is repealed.

Section 68   NR 106.88 (2) is repealed and recreated to read:

NR 106.88 (2) Variance conditions. The department may include all of the following conditions in the permit in lieu of the conditions specified in sub. (1) whenever a chloride variance is g ranted pursuant to s. NR 106.83 :

(a) Chloride monitoring.

(b) An interim limitation for chloride which is effective on the date of permit issuance.

(c) Tier 1 source reduction.

(d) A target value or a target limitation with an appropriate compliance schedule, which is effective on the last day of the permit.

(e) If appropriate, either tier 2 or tier 3 source reduction if the department believes that any of the additional conditions in the tier 2 or tier 3 source reduction activities are reasonable and practical within the term of the permit.

Section 69   NR 106.88 (3 ) is repealed and re created to read:

NR 106.88 ( 3 ) Units for target values. Interim limitations, target values and target limitations established in sub. (2) shall be expressed in the permit as a concentration limitation, in units of mg/L or equivalent units.

Section 70   NR 106.88 (4) is repealed.

Section 71   NR 106.88 ( 5 ) is repealed and re created to read:

NR 106.88 ( 5 ) Monitoring. A determination of compliance with interim, target and calculated limitations and comparison with target values shall be based upon 24-hour composite samples. The department shall determine on a case-by-case basis the monitoring frequency to be required for these limitations.

Section 72   NR 106.88 (6) is repealed .

Section 73   NR 106.89 is repealed and recreated to read:

NR 106.89 (title) Alternative whole effluent toxicity monitoring and limitations for dischargers of chloride.

( 1 ) General. In addition to interim, target and calculated water quality-based effluent limitations and target values for chloride, the department may establish whole effluent toxicity testing requirements and limitations pursuant to ss. NR 106.08 and 106.09 .

( 2 ) Findings. Th e department finds all of the following :

( a) Acute whole effluent toxicity limitations cannot be attained if the effluent concentration of chloride exceeds 2,500 mg/L;

( b) Chronic whole effluent toxicity limitations cannot be attained if the effluent concentration of chloride exceeds 2 times the calculated chronic water quality-based effluent limitation;

(c) Chloride limitations will be used in lieu of WET limitations to attain and maintain narrative criteria in ss. NR 102.04(1)(d) and NR 102.04(4)(d) in the cases where chloride is the sole source of acute or chronic whole effluent toxicity.

( 3 ) Chloride limits in lieu of acute wet limits. Chloride limitations shall be included in the WPDES permit in lieu of acute whole effluent toxicity testing requirements and acute whole effluent toxicity limitations until source reduction actions are completed if any of the following apply :

(a) The permittee can demonstrate to the satisfaction of the department that the effluent concentration of chloride exceeds 2,500 mg/L, or

(b) The permittee can demonstrate to the satisfaction of the department that the effluent concentration of chloride is less than 2,500 mg/L, but in excess of the calculated acute water quality-based effluent limitation, and additional data are submitted which demonstrate that chloride is the sole source of acute toxicity.

( 4) Chloride limits in lieu of chronic wet limits. Chloride limitations shall be included in the WPDES permit in lieu of chronic whole effluent toxicity testing requirements and chronic whole effluent toxicity limitations until source reduction actions are completed if either:

(a) The permittee can demonstrate to the satisfaction of the department that the effluent concentration of chloride exceeds 2 times the calculated chronic water quality-based effluent limitation, or

(b) The permittee can demonstrate to the satisfaction of the department that the effluent concentration of chloride is less than 2 times the calculated chronic water quality-based effluent limitation, but in excess of the calculated chronic water quality-based effluent limitation, and additional data are submitted which demonstrate that chloride is the sole source of chronic toxicity.

(5) Decision documentation. The department shall specify the decision to include chloride limitations in lieu of whole effluent toxicity limitations in the permit fact sheet.

( 6 ) Re-evaluation. The department shall re- evaluate the need for whole effluent toxicity and chloride monitoring or limitations upon permit reissuance .

Section 74   NR 106.91 is amended to read:

NR 106.91 Publicly owned treatment works which accept wastewater from a public water system treating water to meet the primary maximum contaminant levels specified in ch . NR 809 , if not able to meet the calculated limitation, may apply to the department for a variance from the water quality standard used to derive the limitation following the procedure specified in this subchapter . The department shall seek US EPA approval before a variance is included in a WPDES permit . Upon approval, the permittee may be given an interim limitation, a target value, a target limitation and appropriate source reduction requirements, pursuant to s. NR 106.83 in the WPDES permit upon permit reissuance or modification . No calculated limitation, interim limitation, target value, target limitation, or source reduction requirement shall interfere with the attainment of the primary maximum contaminant levels specified in ch. NR 809 .

Section 75   NR 106.91 note is repealed.

Section 76   NR 205.03 (9g) is created to read:

NR 205.03 (9g) “Continuous discharge” means a facility that discharges 24 hours per day on a year-round basis except for temporary shutdowns for maintenance or other similar activities.

Section 77   NR 205.065 and NR 205.066 are created to read:

NR 205.065 Effluent Limitations. (1) Internal waste streams . Permit effluent limitations or effluent standards for discharges of pollutants may be imposed on an internal waste stream when:

(a) I mposing effluent limitations or standards at the point of discharge is impractical or infeasible;

(b) T he internal waste stream has not mixed with other waste streams or cooling water streams; and

(c) The fact sheet under ch. NR 201 states the reasons why it is necessary to impos e effluent limitations or standards on an internal waste stream.

(2) Calculation of effluent limitations for POTWs. For continuous dischargers as defined in s. NR 205.03(10) and subject to ch. NR 210 , effluent limitations shall be based on the maximum effluent flow, expressed as a daily average, that is anticipated to occur for 12 continuous months during the design life of the treatment facility unless it is demonstrated to the department that such a design flow rate is not representative of projected flows at the facility.

(3) Calculation of effluent limitations for other continuous discharges.

(a) For all other discharges not subject to ch. NR 210 , effluent limitations shall be calculated based on actual representative flow values except as provided in subs. (b) and (c).

( b ) For new discharges, production-based effluent limitations shall be estimated using projected production.

( c ) If a facility is expanding or decreasing production levels, the Department may use an estimated alternative production value to calculate production-based effluent limitations .

(4) Intake water credit. If requested by the permittee in the permit application for issuance or reissuance, technology based effluent limitations shall, for each substance or parameter, be adjusted to reflect the discharger’s intake water if the following conditions are met.

(a) Antidegradation requirements in ch. NR 207 are satisfied , if applicable.

(b) The permittee does not discharge raw water clarifier sludge generated from the treatment of intake water.

(c) The permittee demonstrates that applicable technology based effluent limitation for the pollutant would be met in the absence of the pollutant in the intake water.

(d) The permittee demonstrates that the constituents of the pollutant in the effluent are similar to the constituents of the pollutant in the intake water. The intake water is drawn from the same waterbody as defined in s. NR 106.03(11m) which the discharge is made.

(5) Effluent Limit expression. Technology and production based effluent limitations shall be expressed in accordance with this subsection.  Water quality based effluent limitations shall also be expressed in accordance with this subsection except if the Department determines it is impracticable, or if the Department determines that different time periods for expressing limitations is needed to ensure compliance with the applicable water quality standard and different time periods are established in another rule provision for a specific pollutant. Water quality based effluent limitations for toxic pollutants shall be expressed in a permit in accordance with chapter NR 106.

(a) For continuous dischargers as defined in s. NR 205.03(10) and subject to ch. NR 210 , limitations shall be expressed as average weekly and average monthly discharge limitations.

(b) For continuous discharges as defined in s. NR 205.03(10) and not subject to ch. NR 210 , limitations shall be expressed as daily maximum and average monthly discharge limitations.

(c) For seasonal discharges, discharges proportional to stream flow, or other unusual discharge situations that do not meet the definition of a continuous discharge in s. NR 205.03(10) , limitations shall be expressed on a case-by-case basis. The Department shall consider all of the following factors:

1. Frequency and duration of discharge

2. Total mass of discharge

3. Maximum flow rate of discharge

4. Whether the pollutant is subject to a technology based limitation or other limitation expressed by mass, concentration, or other appropriate measure in the WPDES permit.

(6) Mass limitations. (a) A ll pollutants limited in permits shall have limitations, standards or prohibitions expressed in terms of mass except for all of the following situations :

1. Pollutants limited in permits that cannot be appropriately expressed by mass such as pH, chlorine, temperature, radiation, or other pollutants ;

2. When applicable standards and limitations are expressed in terms of other units of measurement; or

3. If limitations expressed in terms of mass are infeasible because the mass of the pollutant discharged cannot be related to a measure of operation.

(b) If a mass limit is included in the permit for a pollutant, the pollutant may be may also be limited in terms of other units of measurement in the permit , and the permit shall require the permittee to comply with both limitations.

(7) Metals . A ll permit effluent limitations, standards, or prohibitions for a metal shall be expressed in terms of total recoverable in a WPDES permit unless any of the following conditions apply :

(a) An applicable effluent standard or limitation has been promulgated and specifies the limitation for the metal in di ssolved or valent or total form;

(b) In establishing permit limitations on a case-by-case basis, it is necessary to express the limitation for the metal in the dissolved or valent or total form to carry out the provisions of the Clean Water Act or chapter 283, Stats. ; or

(c) All approved analytical methods for the metal inherently measure only the dissolved form of the pollutant.

NR 205.066 Permit Conditions. (1) Monitoring. The department shall determine on a case-by-case basis the monitoring frequency to be required for each effluent limitation in a permit. Monitoring shall occur at the point of discharge or at the internal waste stream if the permit limitations are imposed on the internal waste stream pursuant to s. NR 205.065(1) unless an alternative location is established by the department in the WPDES permit.

(2) Production limit documentation. If limits are calculated pursuant to s. NR 205.065(3)(b) the permittee shall submit with the DMR the level of production that actually occurred during each month limits are effective .

(3) Exceedance of production limits. The permittee shall comply with the limitations, standards, and prohibitions calculated pursuant to s. NR 205.065(3)(b) unless the permittee has notified the Department in writing of an anticipated exceedance of the estimated alternative design flow used to calculate limits in which case the permittee may comply with an alternative design flow, not to exceed the production level specified in the notice. Written n otifications must be submitted to the Department at least two days in advance of the exceedance and shall specify the anticipated level, period during which the permittee expects to operate at the alternate level, and the reasons for the anticipated production level increase. Notice of increased discharge must be submitted to the Department for all exceedances not covered in previous notifications.

Section 78   NR 212 Subchapter I (title) is created to read:

SUBCHAPTER I

GENERAL

Section 79   NR 212.01 is amended to read:

NR 212.02 NR 212 .02(1) (1) Purpose. The purpose of this chapter is to establish the procedures, methodologies and requirements to be used by the department for determining total maximum pollutant loadings and corresponding water quality related effluent limitations in accordance with ss. 283.13(5) , 283.15 283.31(3)(d) 3, and 283.83(1)(c) , Stats. Such restrictions are established to attain and maintain the designated uses specified in the water quality standards appearing in chs. NR 102 , 103 and 104 .

Section 80   NR 212 Subchapter I I (title) is created to read (insert before NR 212.02) :

SUBCHAPTER II

EFFLUENT LIMITATIONS FOR BIOCHEMICAL OXYGEN DEMAND DEVELOPED THROUGH WASTELOAD ALLOCATIONS FOR SPECIFIC STREAM SEGMENTS

Section 81   NR 212.02 (1) is repealed and recreated to read:

NR 212.02 NR 212 .02(1) (1) Applicability.   The provisions of this subchapter are applicable to water quality related effluent limitations for biochemical oxygen demand developed through wasteload allocations for the Lower Fox River from milepoints 0-40.0, Upper Wisconsin River from milepoints 171.9-341.4, and Peshtigo River from milepoints 0-12, and established under s. 283.13(5 ) , Stats.

Section 82   NR 212.02 (2) is amended to read:

NR 212.02 NR 212 .02(1) (2)   Nothing in this chapter subchapter shall in any way inhibit, override, preclude or prevent the department from issuing any permit with toxic effluent limits even if such permit limitations would result in more stringent limitations than provided in this chapter subchapter .

Section 83   NR 212.03, NR 212.03 (3), (12), (22), and (24) are amended to read:

NR 212.03 NR 212 .02(1) Definitions. In addition to the definitions and ab breviations in ss. NR 205.03 and 205.04 , the following definitions are applicable to terms used in this chapter subchapter :

(3) "Conventional pollutant" means those pollutants identifie d in section 304 (a) (4) of the federal clean water act amendments of 1977. These pollutants are : biological biochemical oxygen demand (BOD), total suspended solids (TSS), pH, fecal coliform and oil and grease.

(12) "New point source", for the purposes of this chapter subchapter , means a point source which commenced operation after January 1, 1980.

(22) " W aste load Wasteload allocation" , for the purposes of this subchapter , means the allocation resulting from the process of distributing or apportioning the total maximum load to each individual point source, nonpoint sources, reserve capacity and margin of safety.

(24) "Water quality related effluent limitation" means a point source effluent limitation designed to meet applicable water quality standards and which is more restrictive than the categorical effluent limitations. For the purposes of this chapter, water quality related effluent limitations refer to those determined as a result of a waste load wasteload allocation.

Section 84   NR 212.12 (2) (d) is amended to read:

NR 212.12 (2) (d) No bypasses exist occur which are not authorized approved by the department; and

Section 85   NR 212.40 (2) , (b), and (c) are amended to read:

NR 212.40 NR 212.40(2) (2)   Determine baseline loads for each point source subject to the waste load wasteload allocation.

NR 212.40 NR 212.40(2) (2) (b) Nonpublicly−owned point sources between milepoints 40.0 and 19.2. The baseline load expressed in pounds per day for each nonpublicly−owned point source shall be calculated as follows:

Baseline Load = (BPT) (Production) (0.85)

Where: BPT = The final best practicable waste treatment effluent limitations for the point source as provided in chs. ch. NR 284 and 285 , or 217 220 , where applicable, expressed in pounds of BOD5 per ton of production.

Production = The maximum weekly off−machine production during 1973 expressed as tons per day.

0.85 = Adjustment factor to approximate daily average off−machine production.

NR 212.40 (2) (c) Nonpublicly−owned point sources between milepoints 7.2 and 0.0. The baseline load expressed in pounds per day for each nonpublicly−owned point source shall be calculated as follows:

Baseline Load = (BPT) (Production)

Where: BPT = The final best practicable waste treatment effluent limitations for the point source as provided in chs. ch. NR 284 and 285 or 217 220 , where applicable, expressed in pounds of BOD5 per ton of production.

Production = 1977 average daily off−machine production.

Section 86   NR 212.60 (1) , (b), (d), (e), and (g) are amended to read:

NR 212.60 (1) Determine baseline loads for each point source subject to the wasteload waste load allocation.

NR 212.60 (1) (b) The baseline load for each nonpublicly−owned point source located between milepoints 205.3 and 171.9 shall be calculated as follows:

Baseline Load = (BPT) (Production)

Where BPT = The final best practicable waste treatment effluent limitations for the point source as provided in chs. ch. NR 284 and 285 , expressed as pounds of BOD5 per ton of production. If chs. ch. NR 284 and 285 do do es not apply, the best practicable waste treatment effluent limitations as determined under ch. NR 217 220 , shall apply.

Production = The annual average off−machine production during 1978 expressed as tons per day.

NR 212.60 (1) (d) The baseline load for each nonpublicly−owned point source with best practicable waste treatment effluent limitations of less than 500 pounds per day located between milepoints 271.1 and 240.0 shall be calculated as follows:

Baseline Load = (BPT) (Production)

Where BPT = The final best practicable waste treatment effluent limitations for the point source as provided in chs. ch. NR 284 and 285 , or 217 220 , where applicable, expressed as pounds of BOD5 per ton of production.

Production = The maximum weekly off−machine production during 1981 expressed as tons per day.

NR 212.60 (1) (e) The baseline load for each nonpublicly−owned point source with best practicable waste treatment effluent limitations of BOD5 equal to or exceeding 500 pounds per day located between milepoints 271.1 and 240.0 shall be calculated as follows:

Baseline Load = (BPT) (Production)

Where BPT = The final best practicable waste treatment effluent limitations for the point source as provided in chs. ch. NR 284 and 285 or 217 220 , where applicable, expressed as pounds of BOD5 per ton of production.

Production = The average weekly off−machine production expressed as tons per day from March to December 1973 for point sources located between milepoints 271.0 and 258.5 and the BPT WPDES permit limits for 1978 for point sources located between milepoints 258.4 and 258.2 and the average weekly off−machine production expressed as tons per day during 1974 for point sources located between milepoints 258.19 and 249.0 and the average weekly off−machine production expressed as tons per day during 1973 plus the woodroom allowance for sources located between milepoints 248.9 and 240.0.

NR 212.60 (1) (g) The baseline load for each nonpublicly−owned point source located between milepoints 341.4 and 305.9 shall be calculated as follows:

Baseline Load = (BPT) (Production)

Where BPT = The final best practicable waste treatment effluent limitations for the point source as provided in chs. ch. NR 284 and 285 , expressed as pounds of BOD5 per ton of production. If chs. ch. NR 284 and 285 do do es not apply, the best practicable waste treatment effluent limitations as determined under ch. NR 217 220 shall apply.

Production = The annual average off−machine production during 1978 expressed as tons per day.

Section 87   NR 212.70 (1) (a) and (b) are amended to read:

NR 212.70 (1) (a) The baseline load for each publicly−owned point source located between milepoints 9.6 and 0.0 shall be calculated as follows:

Baseline load = (Q) (8.34) (60) + (BPT) (Production)

Where Q = The year 2000 flow projection of the domestic contribution of the influent to the treatment plant expressed in millions of gallons per day

8.34 = Conversion factor

60 = Concentration of BOD5 expressed in milligrams per liter

BPT = The final best practicable waste treatment effluent limitations for the industrial contribution of the influent to the treatment plant as provided in chs. ch. NR 284 and 285 expressed as pounds of BOD5 per ton of production. If chs. ch. NR 284 and 285 do do es not apply, the best practicable waste treatment effluent limitations as determined under ch. NR 217 220 shall apply.

Production = The annual average off−machine production during January 1 to December 1, 1978 expressed as tons per day

NR 212.70 (1) (b) The baseline load for each nonpublicly−owned point source located between milepoints 12.0 and 9.7 shall be calculated as follows:

Baseline load = (BPT) (Production)

Where BPT = The final best practicable waste treatment effluent limitations for the point source which is not discharged to a publicly−owned treatment system as provided in chs. ch. NR 284 and 285 expressed as pounds of BOD5 per ton of production. If chs. ch. NR 284 and 285 do do es not apply, the best practicable waste treatment effluent limitations as determined under ch. NR 217 220 shall apply.

Production = The annual average off−machine production during January 1 to December 1, 1978 expressed as tons per day.

Section 88   NR 212.70 Table 5m (title) is amended to read:

LBS PER DAY OF BOD5

(river mile 238.9 248.9 to 240.0)

Section 89   NR 212 Subchapter III and (title) are created to read (insert after NR 212.70):

SUBCHAPTER III

DEVELOPMENT OF TOTAL MAXIMUM DAILY LOADS AND EFFLUENT LIMITATIONS DEVELOPED THROUGH WASTELOAD ALLOCATIONS

NR 212.71 Applicability. This subchapter establishes the procedures, methodologies and requirements to be used for determining total maximum daily loads and water quality based effluent limitations developed through wasteload allocations for pollutants except as provided in Subchapter II.

NR 212.72 Definitions. In addition to the definitions and abbreviations in ss. NR 205.03 and 205.04 the following definitions are applicable to the terms of this subchapter:

(1) “EPA” means the United States Environmental Protection Agency.

(2) “Impaired water” has the meaning given in s. NR 151.002(16m) .

(3) “ Increased discharge” means any increase in the concentration or mass loading of a pollutant of concern that exceeds an effluent limitation that is in effect in a current WPDES permit.

(4) “Load allocations” means the nonpoint source allocation as defined in s. NR 212.03(14) .

(5) “Loading capacity” means the greatest amount of loading that a water can receive without violating water quality standards.

(6) “Natural background loads” means loads emanating from natural sources, including but not limited to forested and undeveloped lands and from natural processes such as weathering and dissolution, which would exist in the absence of measurable impacts from human activity or influence.

(7) "New discharge" means a point source that discharges the pollutant of concern that commenced operation after the TMDL was approved by U.S. EPA and was not given a wasteload allocation in the TMDL.

(8) “Margin of Safety” means a required component of the TMDL that accounts for the uncertainty in the response of the waterbody to loading reductions.

(9) “Pollutant of concern” means any pollutant discharged that has an applicable TBEL, a wasteload allocation from a TMDL or watershed analysis, or is identified as needing a WQBEL to meet water quality standards.

( 10) “TBEL” means technology-based effluent limitation.

(11) “TMDL” means total maximum daily load and is the sum of the individual wasteload allocations for point sources, load allocations for nonpoint sources , natural background, and a margin of safety. TMDLs can be expressed in terms of mass per time, toxicity, or other appropriate measures that relate to a state's water quality standard.

(12) “Wasteload allocations” refers to the point source allocation as defined in s. NR 212.03(22) .

(13) “ NR 106.52(13) WQBEL” means water quality-based effluent limitation.

NR 212.73 TMDL Development Requirements for Impaired Waters. This section establishes the procedure, methodologies, and requirements to be used for developing TMDLs.

NR 212.73 (1) Prioritization . The department shall identify and create a prioritization list for the development of TMDLs or remediation plans for impaired waters. Remediation plans include, but are not limited to, lake protection and restoration plans, remedial action plans, environmental accountability projects, area wide water quality management plans, and nine key element watershed plans. The priority ranking shall include identification of waters targeted for TMDL development over the next two years including a description of the pollutants causing or expected to cause violations of applicable water quality standards. The Department shall consider any of the following when prioritizing these waters:

(a) Whether i mplementing existing TBELs and WQBELs in WPDES permits is sufficient to achieve water quality standards.

(b) The level of detail required for a TMDL or remediation plan including the severity of the pollution, magnitude of the watershed, and the pollutant being assessed.

(c) Whether e xisting remediation and restoration activities required under local, state, or federal requirements are stringent enough to achieve water quality standards.

NR 212.73 (1) Note: The 303(d) listing and priority setting process is specified in the Wisconsin Consolidated Assessment and Listing Methodology (WisCALM).

NR 212.73 (2) TMDL Development . The Department shall establish TMDLs for impaired waters in accordance with the prioritization in sub. (1). Except as provided in sub. ( 5 ) TMDLs shall be established at levels necessary to attain and maintain applicable numeric and narrative water quality standards with seasonal variations and a margin of safety which takes into account any lack of knowledge concerning the relationship between effluent limitations and water quality. TMDLs shall take into account critical conditions for stream flow, loading, and water quality parameters.

(a) TMDLs shall be established to ensure attainment designated uses and applicable numeric and narrative water quality standards for the pollutant of concern including all applicable numeric and narrative criteria pursuant to chs. NR 102 and NR 105 .

(b) TMDLs may be established using pollutant by pollutant or biomonitoring approach. In many cases both techniques may be needed. Site specific information should be used whenever possible.

(c) TMDLs shall include wasteload allocations for point sources and load allocations for nonpoint sources such that the sum of the allocations is not greater than the loading capacity of the water for the pollutant(s) addressed by the TMDL, minus the sum of natural background loads, the reserve capacity and, if specified, an explicit margin of safety. Allocations shall meet the following requirements:

1. Allocations shall be distributed to sources using a baseline loading condition that is defined in the TMDL.

2 . If allocations in the TMDL are expressed as a concentration, the TMDL shall also indicate the flows, including effluent flows, assumed in the analyses.

3 . If multiple EPA approved TMDLs are prepared for impaired waters , and the TMDLs include allocations for the same pollutant for one or more of the same sources, then the applicable allocations that are protective of both immediate and downstream segments shall be used for TMDL implementation, including WPDES permitting.

4 . Pollutant degradation and transport may be considered when developing allocations.

5 . Natural background loads may be accounted for in a TMDL through an allocation to a single category or through individual allocations to applicable sources of natural background loads.

6 . Nonpoint sources may be accounted for in a TMDL through an allocation to a single category or through individual load allocations to various nonpoint sources.

7 . Point source dischargers covered through individual permits shall be assigned indi vidual waste load allocations. Point source dischargers covered through general permits may be accounted for through an allocation to a single category or through individual wasteload allocations.

(d) TMDLs shall include a margin of safety sufficient to account for technical uncertainties in establishing the TMDL and shall describe the manner in which the margin of safety is determined and incorporated into the TMDL. The margin of safety may be provided explicitly by leaving a portion of the loading capacity unallocated, implicitly by using conservative modeling assumptions to establish wasteload allocations and load allocations or a combination thereof. If a portion of the loading capacity is left unallocated to provide a margin of safety, the amount left unallocated shall be documented. If conservative modeling assumptions are relied on to provide a margin of safety, the specific assumptions providing the margin of safety shall be described.

(e) A portion of the TMDL may be allocated to a reserve capacity to account for new or increased discharges, or other sources not allocated in the TMDL . Where such reserve allocations are not included in a TMDL, any increased loadings of the pollutant for which the TMDL was developed that are due to a new or expanded discharge shall not be allowed unless the TMDL is revised in to include an allocation for the new or expanded discharge or the new or expanded discharge is offset by a reduction of the pollutant in the watershed covered by the TMDL .

NR 212.73 (3) Monitoring data . Monitoring data shall be collected to support the development of the TMDL and track implementation of a TMDL. Monitoring data shall be used for all of the following:

(a) Monitoring data shall be used to demonstrate progress towards achieving water quality standards such as quantify pollutant reductions made through implementation of the TMDL and evaluating the effectiveness of controls being used to implement the TMDL.

(b) Monitoring data shall be used to validate the assumptions and scientific analysis used to establish the TMDL or revise the TMDL, if necessary.

NR 212.73 (4) Reasonable assurance. A TMDL, implementation plan for a TMDL, or remediation plan shall provide reasonable assurances that water quality standards will be attained within a reasonable timeframe. Determining the reasonable period of time in which water quality standards will be met is a case-specific determination considering a number of factors including, but not limited to: receiving water characteristics including persistence, behavior and ubiquity of pollutants of concern, the types of remedial activities necessary, and available regulatory and non-regulatory controls.

NR 212.74 Developing TMDLs for Nearshore and Open Waters of the Great Lakes. This section describes requirements for deriving TMDLs for Open Waters of the Great Lakes (OWGL), inland lakes and other waters of the Great Lakes System with no appreciable flow relative to their volumes. This section applies to TMDLs for all pollutants excluding the following: alkalinity, ammonia, bacteria, biochemical oxygen demand (BOD), chlorine, color, dissolved oxygen, dissolved solids, pH, phosphorus, salinity, temperature, total and suspended solids, turbidity, and whole effluent toxicity. In addition to the requirements specified in NR 212.73, TMDLs in this section shall also meet all of the following:

(1) TMDLs shall reflect, where appropriate and where sufficient data are available, contributions to the water column from sediments inside and outside of any applicable mixing zones. TMDLs shall be sufficiently stringent so as to prevent accumulation of the pollutant of concern in sediments to levels injurious to designated or existing uses, human health, wildlife and aquatic life.

(2) TMDLs shall reflect, where appropriate and where sufficient data are available, discharges resulting from wet weather events.

(3) TMDLs shall reflect, where appropriate and where sufficient data are available, background concentrations of pollutants stemming from atmospheric deposition, sediment release or resuspension, or as a result of chemical reactions.

NR 212.75 Developing TMDLs for Great Lakes Systems Tributaries and Connecting Channels. This section describes conditions for deriving TMDLs for tributaries and connecting channels of the Great Lakes System that exhibit appreciable flows relative to their volumes. This section applies to TMDLs for all pollutants excluding the following: alkalinity, ammonia, bacteria, biochemical oxygen demand (BOD) , chlorine, color, dissolved oxygen, dissolved solids, pH, phosphorus, salinity, temperature, total and suspended solids, turbidity, and whole effluent toxicity. In addition to the requirements specified in NR 212.73, TMDLs in this section shall also meet all of the following:

(1) TMDLs shall reflect, where appropriate and where sufficient data are available, contributions to the water column from sediments inside and outside of any applicable mixing zones. TMDLs shall be sufficiently stringent so as to prevent accumulation of the pollutant of concern in sediments to levels injurious to designated or existing uses, human health, wildlife and aquatic life.

(2) TMDLs shall reflect, where appropriate and where sufficient data are available, discharges resulting from wet weather events.

(3) TMDLs shall reflect, where appropriate and where sufficient data are available, background concentrations of pollutants stemming from atmospheric deposition, sediment release or resuspension, or as a result of chemical reactions.

(4) Design flows shall be used unless data exist to demonstrate that an alternative stream design flow is appropriate for stream-specific and pollutant-specific conditions. For purposes of calculating a TMDL, the stream design flows shall be all of the following :

(a) The 7-day, 10-year stream design flow (7Q10), or the 4-day, 3-year biologically-based stream design flow for chronic aquatic life criteria or values;

(b) The 1-day, 10-year stream design flow (1Q10), for acute aquatic life criteria or values;

(c) The harmonic mean flow for human health criteria or values;

(d) The 90-day, 10-year flow (90Q10) for wildlife criteria.

(e) TMDLs, calculated using dynamic model ing do not need to incorporate the stream design flows specified in a. through d. of this procedure.

(5) The loading capacity is initially calculated at the farthest downstream location for the impaired reach by multiplying the applicable criterion or target value by the flow condition described in sub. ( 4 ). The loading capacity is then compared to the loadings at sites within the basin to assure that applicable numeric criteria or values for a given pollutant are not exceeded at all applicable sites. The lowest load is then selected as the loading capacity to be consistent with the attainment of each applicable numeric criterion or value for a given pollutant.

NR 212.76 Establishing WQBELs for Publicly and Privately Owned Wastewater Facilities or Treatment Works.  

(1) W qbel c alculation procedures . Calculation of WQBELs derived from TMDL wasteload allocations shall be derived consistent with the wasteload allocation and assumptions of an EPA approved TMDL . The department shall use scientifically defensible methods to calculate these WQBELs . All of the following conditions shall apply when calculating WQBELs derived from TMDL wasteload allocations:

(a) WQBELs shall be expressed as mass limitations unless the pollutant cannot appropriately be expressed by mass or a mass limitation is infeasible because the mass of the pollutant cannot be related to a measure of operation.

(b) When establishing WQBELs in WPDES permits t he department shall ensure that substances are not present in amounts which are acutely toxic to animals, plants or aquatic life in all surface waters including those portions of the mixing zone normally habitable by aquatic life and effluent channels as required by s. NR 102.04(1) .

(c) When establishing WQBELs in WPDES permits t he department shall ensure that substances are not exceeding applicable chronic toxicity criteria (CTC), wildlife criteria (WC), taste and odor criteria (TOC), human threshold criteria (HTC), human cancer criteria (HCC), and secondary values, as specified in chs. NR 102 to 105 , after dilution with an appropriate allowable quantity of receiving water flow unless the conditions specified in s. NR 102.05(3) require less dilution or no dilution be allowed.

(2) WQBEL c alculation procedures in Great Lake Basin. In addition to the requirements in sub. (1), WQBELs derived from TMDL s pursuant to ss. NR 212.74 and NR 212.75 shall also meet all of the following:

(a) WQBELs shall be sufficiently stringent to ensure that accumulation of the pollutant of concern cannot occur in sediments at levels injurious to designated or existing uses, human health, wildlife, or aquatic life.

(b) When establishing WQBELs in WPDES permits t he department shall assume that the pollutant of concern does not degrade over time unless any the following conditions are met:

1. Scientifically valid field studies or other relevant information demonstrate that degradation of the pollutant is expected to occur under the full range of environmental conditions expected;

2 . Scientifically valid field studies or other relevant information address other factors that affect the level of pollutants in the water column including, but not limited to, suspension of sediments, chemical speciation, and biological and chemical transformation.

( 3 ) Mixing zones for bioaccumulative chemicals of concern (BCCs). When

NR 217.16(1)(c) calculating WQBELs derived from TMDL wasteload allocations for BCCs the department shall be consistent with and no less stringent than s . NR 106.06(2) .

( 4 ) Expression of limits. WQBELs derived from TMDL wasteload allocations shall be expressed consistent with the provisions specified in ch. NR 205.065 unless impracticable or an alternative expression of limitations is determined appropriate by the department and is consistent with the assumptions of the TMDL.

( 5 ) Compliance schedules. Compliance with the WQBELs derived from TMDL wasteload allocations shall be attained as soon as reasonably possible, but no later than the expiration date of the permit unless extended compliance schedules are authorized in ch. NR 217 , other administrative rules or an approved area wide water quality management plan pursuant to ch. NR 121 . When a permit is issued , reissued or modified with new WQBELs based on a TMDL established using the procedures in this subchapter , the Department may contain a compliance schedule to achieve compliance with the TMDL based limitation if the permitttee’s treatment system is unable to immediately comply with the limitation.

(6 ) Relationship of wqbels derived from tmdl wasteload allocations and other wqbels . The department may include WQBELs derived from TMDL wasteload allocations in a WPDES permit in addition to, or in lieu of, other WQBELs.

NR 212.77 Public Participation

(1) The department shall conduct an informational public hearing and provide an opportunity for the public comment on a proposed TMDL before the TMDL is submitted to EPA for approval. The minimum time period for written comments shall be 30 days from the date of public notice of a TMDL. T he department shall post notice of a proposed TMDL on the department’s website .

(2) Once a TMDL is approved by EPA, the TMDL is automatically incorporated into areawide water quality management plan, lake management plans, or remedial action plans.

(3) The department may not impose a WQBEL based on a TMDL in a WPDES permit pursuant to s. NR 212.76(6) , until the TMDL has been approved by EPA.

(4) The department shall public notice and provide an opportunity for comment on a calculated WQBEL that is derived from the EPA approved TMDL during the public notice and comment period provided in chapter NR 203 and ch. 283 , Stats.

Section 90   NR 217.14 (2) and (3) are amended to read:

NR 217.14 (2) Concentration effluent limitations calculated under s. NR 217.13 shall be expressed as a monthly average in permits, except for concentrations of less than or equal to 0.3 mg/L where limitations may be expressed as annual averages six-month averages . If a concentration limitation expressed as an annual average a six-month average is included in a permit, a monthly average concentration limitation equal to three times the water quality based effluent limitation calculated under s. NR 217.13 shall also be included in the permit.

NR 217.14 (3) Concentration effluent limitations as calculated under s. NR 217.13 shall be converted into mass effluent limitations using the effluent flow identified in s. NR 217.13 and an appropriate conversion factor, and expressed as a monthly average in the permit, except for concentration based limitations of less than or equal to 0.3 mg/L where mass limitations may be expressed as annual averages six-month averages .

Section 78 . Effective Date . This rule takes effect on the first day of the month following publication in the Wisconsin Administrative Register as provided in s. 227.22 (2) (intro.) , Stats.

Section 79 . Board adoption. This rule was approved and adopted by the State of Wisconsin Natural Resources Board on [DATE] .