NR 211.13(2)(d)1.1. For purposes of this paragraph “measurable” refers to the ability of the analytical method to quantify as well as identify the presence of the pollutant in question. “Limit of detectability” refers to the lowest limit at which the analytical method can quantify the pollutant in question.

NR 211.13(2)(d)2.2. For each sample, removal shall be calculated by dividing the difference between the concentrations of a pollutant in the POTW’s influent and effluent by the influent concentration. If the number of samples with measurable concentrations is greater than 12, the consistent removal is the average of the lowest half of the removals. If the number of samples with measurable concentrations is between 8 and 12, the consistent removal is the average of the lowest 6 removals. If less than 8 samples have measurable concentrations, the department may approve a means for demonstrating consistent removal on a case-by-case basis.

NR 211.13(2)(d)3.3. If a substance is measurable in the influent but not in the effluent, the effluent concentration may be assumed to be the limit of measurement, and those data may be used by the POTW, subject to approval by the department.

NR 211.13(2)(e)1.a.a. All industrial users to which the POTW proposes to apply removal credits have demonstrated the ability to contain or reduce discharges or increase pretreatment to compensate for the removal not being provided by the POTW during circumstances in which overflow can be reasonably expected to occur;

NR 211.13(2)(e)1.b.b. The POTW has identified circumstances in which an overflow event can be reasonably expected to occur and has a notification plan or other viable plan to ensure that industrial users will learn of an impending overflow event in sufficient time to contain or reduce discharges or increase pretreatment to prevent untreated overflow from occurring;

NR 211.13(2)(e)1.d.d. All industrial users to which the POTW proposes to apply removal credits have demonstrated the ability and commitment to collect and make available, upon request, to the POTW, department or EPA, daily flow reports or other data sufficient to demonstrate that all discharges from regulated processes containing the pollutant for which the removal credit is requested were contained, reduced or subject to increased pretreatment during all circumstances in which an overflow was reasonably expected to occur.

NR 211.13(2)(e)2.b.b. The POTW is complying with all WPDES permit requirements and any additional requirements in any order or decree issued pursuant to the Federal Water Pollution Control Act, (33 U.S. Code section 1251 et seq.), (Clean Water Act), affecting combined sewer outflows. These requirements include, but are not limited to, any requirements contained in EPA’s Combined Sewer Overflow Control Policy.

NR 211.13(3)(3) Provisional credits. For pollutants which are not discharged currently (i.e., new or modified facilities, or production changes) the POTW may apply for authorization to give removal credits prior to the initial discharge of the pollutant. Consistent removal for the first 18 months of discharge shall be based on data from treatability studies or demonstrated removal at other treatment facilities where the quality and quantity of influent are similar. Eighteen months after initial discharge of pollutants, consistent removal shall be demonstrated pursuant to the requirements of sub. (2). If the POTW cannot demonstrate consistent removal pursuant to the requirements of sub. (2), the authority to grant provisional removal credits shall be terminated by the department. All industrial users to whom the revised discharge limits had been applied shall achieve compliance with the applicable categorical pretreatment standards within a reasonable time, not to exceed the period of time prescribed in the applicable categorical pretreatment standards, as may be specified by the department.

NR 211.13(4)(4) Terms and conditions for POTW granting and continuing conditional removal credits. A POTW required to develop a local pretreatment program by s. NR 211.20 may give removal credits pending approval of the program under the following terms and conditions:

NR 211.13(4)(a)(a) All industrial users who are currently subject to a categorical pretreatment standard and who apply for a conditional removal credit shall submit to the POTW the information required in s. NR 211.15 (1) (a) to (h). However, new or modified industrial users shall only submit the information required by s. NR 211.15 (1) (a) to (f), pertaining to the categorical pretreatment standard as modified by the removal credit. The industrial users shall indicate what additional technology, if any, will be needed to comply with the categorical pretreatment standard as modified by the removal credit;

NR 211.13(4)(b)(b) The POTW shall have submitted to the department an application for pretreatment program approval meeting the requirements of subch. II of ch. NR 211 in a timely manner, not to exceed the time limitation set forth in a compliance schedule for development of a pretreatment program included in the POTW’s WPDES permit, but in no case later than July 1, 1983, where no permit deadline exists;

NR 211.13(4)(d)(d) If a POTW receives authority to grant conditional removal credits and the department subsequently makes a final determination, after appropriate notice, that the POTW failed to comply with the conditions in pars. (b) and (c), the authority to grant conditional removal credits shall be terminated by the department. All industrial users to whom the revised discharge limits had been applied shall achieve compliance with the applicable categorical pretreatment standard within a reasonable time, not to exceed the period of time prescribed in the applicable categorical pretreatment standard, as may be specified by the department.

NR 211.13(4)(e)(e) If a POTW grants conditional removal credits and the POTW or the department subsequently makes a final determination, after appropriate notice, that the industrial user failed to comply with the conditions in par. (a), the conditional credit shall be terminated by the POTW or the department for the non-complying industrial user. The industrial user to whom the revised discharge limits had been applied shall achieve compliance with the applicable categorical pretreatment standard within a reasonable time, not to exceed the period of time prescribed in the applicable categorical pretreatment standard, as may be specified by the department. The conditional credit may not be terminated where a violation of the provisions of this paragraph results from causes entirely outside of the control of the industrial user or the industrial user had demonstrated substantial compliance.

NR 211.13(4)(f)(f) The department may decide not to review an application for conditional removal credit authority, in which case the conditionally revised discharge limits shall become effective and remain in effect until reviewed by the department. This review shall be conducted in accordance with the procedures of s. NR 211.30 before any pretreatment program approval or any WPDES permit reissuance pursuant to the pretreatment program approval.

NR 211.13(5)(5) POTW application for authorization to give removal credits.

NR 211.13(5)(a)(a) Any POTW that wants to give removal credits or modify existing ones shall apply for authorization from the department. Such application may be submitted at any time and shall include the following information: