Best management practices (BMPs) are schedules of activities, prohibitions of practices, maintenance procedures, and other management practices to prevent or reduce the pollution of waters of the state. They can include treatment requirements, operating procedures, and practices to control plant site runoff, spillage or leaks, sludge or waste disposal, or drainage from raw material storage.

Existing rules contain best management practice requirements for land application activities, storm water runoff, and runoff from Concentrated Animal Feeding Operations (CAFOs). Federal rules (40 CFR 122.44 (k)) identify certain other circumstances when BMPs must be included in permits.

The proposed rule contains provisions to conform to federal requirements for when the department must include best management practices (BMPs) in permits to control or abate the discharge of pollutants. The proposed rule states that BMPs will be included when numeric effluent limitations are infeasible or when BMPs are reasonably necessary to achieve effluent limitations and standards or to carry out the purposes and intent of the Clean Water Act, consistent with 40 CFR 122.44(k)(3) and (4).

Antibacksliding (Issue 14):

Pursuant to 40 CFR 122.44 (l) and the Clean Water Act, 33 USC 1342(o), the water quality based effluent limitations, best professional judgment limitations, and interim limitations, standards, or conditions in any reissued permit must be at least as stringent as those in the previous permit, with some exceptions. These provisions are referred to as “antibacksliding” provisions. Existing state rules contain antidegradation procedures to prevent lowering of water quality in surface waters unless necessary, but existing rules do not specifically contain the antibacksliding requirements in 40 CFR 122.44(l) and the Clean Water Act 33 USC 1342(o). The proposed rules add provisions to conform to federal requirements.

Compliance Schedules (Issues 15 and 29):

Federal rules contain requirements for compliance schedules that are applicable to state programs (see 40 CFR 123.25(18) and 122.47(a)) and Great Lakes states (40 CFR 123.25(38) and 40 CFR Part 132)). Existing state rules contain specific provisions for compliance schedules for toxic and organoleptic substances, ammonia, temperature, and phosphorus. The proposed rule adds a new section for compliance schedule requirements to ch. NR 205, expanding the compliance schedule provisions to all appropriate situations, not just upgrades to meet limits for toxic and organoleptic substances, ammonia, temperature, or phosphorus. The proposed rule also revises the compliance schedule requirements in chapter 106 for consistency with 40 CFR 122.47 and with 40 CFR 132, Appendix F, Procedure 9 for Great Lakes dischargers.

The proposed rule also repeals s. NR 106.13, which allows a compliance schedule for POTWs accepting leachate from a solid waste facility. This specific allowance is not present in 40 CFR 122.47.

The proposed rule also clarifies that if a permitted facility has an effective water quality based limitation for a pollutant in a permit and the facility is treating the pollutant to comply with the limitation, there is continued reasonable potential to exceed the water quality standard and the limit must remain in a reissued permit.

Expression of Limits in Permits when Permittee Disposes of Pollutants into Wells or Publically Owned Treatment Works or by Land Application (Issue 20):

The federal rule at 40 CFR 122.50 provides for an adjustment to effluent limitations when part of a discharger’s process wastewater is disposed of to a POTW, a well, or to a land application site and the other part is discharged to a surface water. Since state law doesn’t allow injection of wastewater directly into a private or public well, the proposed rules do not include adjustments to limitations for a direct well injection.

The proposed rule codifies the department’s current operating procedure for calculating limitations in these circumstances and establishes consistency in state rules with federal regulations.

Definitions of “Point Source” and “Pollutant” (Issue 44):

Federal law (40 CFR 122.2) contains definitions of “point source” and “pollutant.” These definitions apply to the requirements for state programs in 40 CFR 123.25. EPA raised a question about whether state law definitions were consistent with federal law. This issue was addressed through an Attorney General’s Statement dated January 19, 2012. To clarify state rules, the proposed rule adds “landfill leachate collection system” to the definition of “point source” and “filter backwash” to the “definition of “pollutant.” The proposed revisions to the definitions in rules are consistent with the Attorney General’s interpretation of the state statutory definitions provided in the January 19, 2012 statement.

Expedited Variances (Issue 46):

Federal regulations at 40 CFR 122.21 (o) allow permit variance applications to be submitted before a permit is reissued and time extensions for filing variance requests. The federal variance procedures are applicable to state programs (40 CFR 123.25(4)). The proposed rule allows the department to accept variance applications before a permit is reissued. This is consistent with the federal regulations and is an existing practice for variances to water quality based effluent limitations pursuant to s. 283.15 (2) (a), Wis. Stats. The proposed rules also establish expedited variance request procedure for variances to technology based limitations in chapter NR 220, consistent with 40 CFR 122.21(o) and (m).