NR 106.11NR 106.11 Multiple discharges. Whenever the department determines that more than one discharge may be affecting the water quality of the same receiving water for one or more substances, the provisions of this chapter shall be used to calculate the combined allowable load from the discharges necessary to meet the water quality criteria for the substances. The resultant combined allowable load shall be divided among the various discharges using an allocation method based on site-specific considerations. Whenever the department makes a determination under this section, the department shall notify all permittees who may be affecting the water quality of the same receiving water of the determination and any limitations developed under this section. Permittees shall be given the opportunity to comment to the department on any determination made under this section.

NR 106.115(1)(1) For the chlorinated dibenzo-p-dioxins (CDDs) listed in Tables 8 and 9 in ch. NR 105, the potential adverse additive effects of all dioxin (CDD) and chlorinated dibenzofuran (CDF) congeners in effluents shall be accounted for as specified in this section.

NR 106.115(2)(2) The Toxicity Equivalency Factor (TEF) in Table 1 and Bioaccumulation Equivalency Factor (BEF) in Table 2 shall be used when calculating a 2,3,7,8-TCDD toxicity equivalence concentration in effluent to be used when implementing both human health noncancer and cancer criteria. The chemical concentration of each CDD and CDF in effluent shall be converted to a 2,3,7,8-TCDD toxicity equivalence concentration in effluent by using the following equation:

NR 106.115 HistoryHistory: Cr. Register, August, 1997, No. 500, eff. 9-1-97; CR 03-050: renum. from NR 106.16 Register February 2004 No. 578, eff. 3-1-04; CR 09-123: am. (1) Register July 2010 No. 655, eff. 8-1-10; CR 15-085: am. Table 1 (title), Table 2 (title) Register August 2016 No. 728, eff. 9-1-16.

NR 106.117(1)(a)(a) In this subsection, the following definitions apply:

NR 106.117(1)(b)(b) The first permit issued by the department to a new source or a new discharger shall contain a schedule of compliance only when necessary to allow a reasonable opportunity to attain compliance with state or federal limitations promulgated after commencement of construction but less than 3 years before commencement of the discharge.

NR 106.117(1)(c)(c) For recommencing dischargers, a schedule of compliance shall be included in the permit only when necessary to allow a reasonable opportunity to attain compliance with limitations promulgated less than 3 years before recommencement of the discharge.

NR 106.117(3)(a)(a) Time for compliance. Any schedule of compliance under this section shall require compliance as soon as possible but may not extend beyond any applicable federal or state statutory deadlines. The schedule also may not extend beyond 5 years from the date that the permit is reissued or modified to include the new or more stringent effluent limitation, except as provided in par. (b) or as provided in other chapters.

NR 106.117(3)(b)(b) Great Lakes dischargers. For an existing discharger to the Great Lakes system with a permit that was originally issued before March 23, 1997, if the effluent limitation is based on a secondary value under s. NR 105.03 (25), the permit shall require compliance with the secondary value based limitation within a reasonable period of time, no later than 5 years after permit reissuance or modification to include the limitation. The compliance schedule may allow the permittee additional time to conduct studies for the purpose of revising the secondary value or to develop a criterion if requested by the permittee in accordance with s. NR 106.07 (8). The time period allowed for such studies may not exceed 2 years. In cases where the permittee wishes to conduct a study on the secondary value, the permit also shall contain a reopener clause, requiring a permit modification if the department determines the specified studies demonstrate that a revised limitation is appropriate. Any revised limitation shall be incorporated through a permit modification and a reasonable time period, up to 5 years, may be allowed for compliance, but in no case may the compliance schedule for the revised limitation extend beyond 7 years from the date the secondary value based limitation was initially included in the permit.