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(d), which requires that POTWs with continuous discharges receive limits expressed as monthly average and weekly average limits;
40 CFR 122.47, which specifies the protocols and restrictions for establishing compliance schedules in WPDES permits;
40 CFR Part 132, Appendix F, Procedure 9, which authorizes compliance schedule extensions within the Great Lakes Basin.7. Comparison with Similar Rules in Adjacent States:
For this rule package, comparisons were made to the other states in EPA Region 5 (Illinois, Indiana, Michigan, Minnesota, and Ohio) and Iowa. All of the Region 5 states are subject to the Clean Water Act, BEACH Act, and EPA regulations. As Iowa does not have any coastal waters, they are not subject to the BEACH Act but are still subject to the Clean Water Act and EPA regulations. A brief comparison with these states is provided below on the key issues addressed in this rule package.
Bacteria Water Quality Criteria for Recreation
The other states have different criteria for each of their recreation use subcategories. Because Wisconsin has a single recreation use category, only the criteria for the “full contact” category were considered in this comparison. Wisconsin is not considering a secondary contact use category at this time because EPA does not currently have recommended criteria for secondary contact waters. Because Illinois is currently revising its criteria for bacteria, they were not included in these comparisons.
Pathogen Indicator
All of the states that were used for this comparison, except Illinois, use E. coli as the pathogen indicator. Illinois is currently in the process of revising its criteria to use E. coli. In this rule package, the department selected E. coli as the pathogen indicator for Wisconsin’s criteria, consistent with these other states.
Criteria Magnitude
Indiana and Iowa have short- and long-term criteria based on EPA’s 1986 recommendations. Michigan also bases its criteria on EPA’s 1986 recommendations but uses single day GM instead of the SSM as its short-term criterion. Minnesota currently has criteria based on EPA’s 1986 recommendations. Ohio revised its criteria in 2016 based on EPA’s 2012 recommendations.
In this rule package, the department selected an approach that is consistent with Ohio. In the revised rule, EPA’s 2012 recommendations were used to establish Wisconsin’s criteria because they are based on the latest scientific knowledge and allow the natural variation in bacteria levels to be considered when assessing the waterbody.
Illness Rate
In its 2012 recommendations EPA developed criteria based on two illness rates, with the higher illness rate corresponding with the level of protection provided by the EPA’s 1986 recommendations. Ohio’s criteria are based on the higher illness rate. A comparison to the other states was not made as their criteria were not based on the 2012 recommendations.
In this rule package, the department selected an approach that is consistent with Ohio. In the revised rule, the department selected the criteria based on the higher illness rate because that rate is consistant with EPA’s previous and current recommended risk level, and selection of the lower illness rate would unnecessarily increase the number of impaired waters and beach advisories.
Criteria Duration
All of the other states, except for Iowa, have duration specified as part of their criteria. Michigan, Minnesota, and Indiana’s criteria are based on EPA’s 1986 recommendations. Both Michigan and Indiana use a monthly duration for both the geometric mean and single sample maximum criteria. Michigan uses geometric mean values for both its long- and short-term criteria and uses a duration of a month for the long-term criterion and a day for the short-term criterion. Ohio’s criteria are based on EPA’s 2012 recommendations and use a duration of 90 days for both its GM and statistical threshold value criteria.
In this rule package, the department selected an approach that is consistent with Ohio and is acceptable to EPA. The revised rule specifies a duration of 90 days for both the GM and STV criteria because it allows the department to adequately protect the recreation designated use while assessing Wisconsin’s waters in a comprehensive and informative manner.
Bacteria Site-Specific Criteria
None of the other states have language specific to the development of site-specific criteria for bacteria.
Variance Criteria
These variances, proposed for deletion, are specific to individual waterbodies in Wisconsin. A comparison to the other states was not conducted.
Permit Requirements
To ensure recreation is protected in Wisconsin’s waters, dischargers of treated human waste are required to meet effluent limits for bacteria. The requirements described in this section apply to facilities that are subject to ch. NR 210, Wis. Admin. Code, including publicly owned treatment works and privately owned domestic sewage treatment works. Only the requirements for dischargers to “full contact” use waters were considered in this comparison as Wisconsin has a single recreation use category. Because Illinois is currently revising its permit requirements for bacteria, they were not included in these comparisons. Effluent Limitations
Effluent limits vary by state. For this comparison, only the limits that apply during the time frame in which the bacteria criteria apply were included. Minnesota and Michigan have effluent limits for fecal coliform that are based on EPA’s 1976 recommended criteria. Minnesota has a monthly limit equal to the geometric mean criterion and does not have specified monitoring requirements. Michigan has monthly and weekly limits, with the monthly limit equal to the GM criterion and the weekly limit equal to the “10% exceedance” criterion. Michigan requires a minimum of 5 samples for the monthly limit and 3 samples for the weekly limits.
Iowa and Indiana have effluent limits for E. coli that are based on EPA’s 1986 recommended criteria. Iowa has a monthly limit equal to the GM criterion and requires a minimum of 5 samples a month, with monitoring conducted for one month during each quarter of the recreation season. Indiana has both monthly and daily limits. The monthly limit equals the GM criterion and the daily limit equals the SSM criterion for designated bathing beaches. The daily limit only applies when 10 or more samples have been collected in a month. Indiana bases its minimum monitoring requirements on the average design flow of the facility.
Ohio has monthly and weekly effluent limits for E. coli. Limits for dischargers to the Ohio River are based on EPA’s 1986 recommended criteria while limits for dischargers to all other waters are based on EPA’s 2012 recommended criteria. These limits differ because of specific requirements from the Ohio River Valley Water Sanitation CommissionFor the Ohio River dischargers, the monthly limit equals the GM criterion (rounded) and the weekly limit equals the SSM criterion for designated bathing beaches (rounded). For dischargers to other Ohio waters, the monthly limit equals the GM criterion and the weekly limit is calculated using procedures in the U.S. EPA’s Technical Support Document for Water Quality-Based Toxics Control.
In this rule package, the department selected EPA’s recommended “end-of-pipe” approach of applying both the GM and STV criteria to the end-of-pipe discharge, which “is considered to be the simplest and most common method to develop the effluent limits for pathogens and pathogen indicators” (U.S. EPA. 2015. FAQ: NPDES Water-Quality Based Permit Limits for Recreational Water Quality Criteria). The monthly geometric mean is used by several states. While neighboring states use a wide variety of approaches to the short-term limit, the STV (one type of short-term limit) is not currently applied by any of Wisconsin’s neighboring states.
8. Summary of Factual Data and Analytical Methodologies Used and How Any Related Findings Support the Regulatory Approach Chosen:
The methodology identified in this rule package is based on Clean Water Act and Great Lake Initiative requirements and on EPA guidance including the U.S. EPA (March 1991) Technical Support Document for Water Quality-based Toxics Control. PB91-127415: Office of Water.
9. Analysis and Supporting Documents Used to Determine the Effect on Small Business or in Preparation of an Economic Impact Report:
This rule is expected to have a moderate economic impact estimated at an annual cost of approximately $2.1 million (rounded to two significant figures). The costs incurred will be due to increased disinfection needed for some facilities to comply with E. coli permit limits, and changes in analytical methods associated with monitoring each type of bacteria. These changes solely pertain to facilities subject to ch. NR 210, Wis. Adm. Code (i.e., publicly owned treatment works and privately owned domestic sewage treatment works). Of 354 total facilities that disinfect, over half (208) are expected to already meet permit limits based on E. coli with no additional treatment. The department estimates that 41% (146) will need to increase treatment, with a total annual cost of increased treatment for all facilities combined of $2,100,000. We anticipate the total annual cost of sample analysis for facilities that monitor to be $53,000. Cost savings for 20 facilities that will be able to reduce monitoring are estimated at $22,000. Costs for increased disinfection were estimated using a first-order kinetics model, in which a multiplier representing an increased level of ultraviolet or chlorine disinfection needed beyond the current treatment level was computed for each facility. The cost estimates developed in this analysis included capital costs and operation and management costs. Capital costs were amortized over 20 years using a nominal discount rate of 3.6%. Costs for lab analysis were estimated using information obtained from several commercial laboratories and manufacturers of lab equipment. Methods are described in this rule’s Fiscal Estimate/Economic Impact Analysis.
For small businesses, costs were determined in the same way. The total annual costs for small businesses are expected to be minimal, with an estimated total compliance cost of $2,200 for five facilities combined.
10. Effect on Small Business (initial regulatory flexibility analysis):
Five of the identified facilities may be affected small businesses, such as mobile home parks or nursing homes. Costs for small businesses were estimated in the same way as costs for the overall group of facilities, but using just the subset of these five facilities. Some facilities may need to increase disinfection to comply with E. coli permit limits and/or change lab analysis procedures. The total annual compliance cost for these facilities combined is estimated at $2,200. This includes an estimated cost of $1,500 for increasing disinfection, and a cost of $660 for switching analytical methods from fecal coliform to E. coli during the recreation period.
11. Agency Contact Person: Kristi Minahan, Wisconsin Department of Natural Resources, Bureau of Water Quality WY/3, P.O. Box 7921, Madison, WI 53707-7921;
12. Place where comments are to be submitted and deadline for submission:
Written comments may be submitted at the public hearings, by regular mail or email to:
Kristi Minahan
Wisconsin Department of Natural Resources
Bureau of Water Quality WY/3
101 S. Webster St.
P.O. Box 7921
Madison, WI 53707-7921
