Section NR 217.19 - Variances for stabilization ponds and lagoon systems(1) GENERAL. (a) An owner or operator of a permitted wastewater treatment system that consists primarily of a stabilization pond system or a lagoon system may apply for a variance to the phosphorus water quality based effluent limitations pursuant to s. 283.15(4) (a) 1 f., Stats., using the procedures in this section. Note: Stabilization ponds and lagoons are operated primarily by communities serving a population of 2000 or less and small industries. With currently available technology that could be used in conjunction with stabilization ponds or lagoons, it is unlikely that phosphorus water quality based effluent limits less than 1 mg/L can be consistently met. To meet phosphorus water quality based effluent limits of less than 1 mg/L, it will be necessary for owners of the systems to construct new wastewater treatment plants which could result in substantial and widespread adverse social and economic impacts.
(b) A new discharger may not receive approval for a variance under this section or pursuant to any other variance procedure.(2) APPLICATION FOR A VARIANCE. (a) The application for a variance under this section shall be submitted with the WPDES permit application for reissuance, or within 30 days after the permittee receives written notification of the proposed phosphorus limits, if the notification occurs later. The application shall be submitted on the phosphorus lagoon and stabilization pond variance form made available from the department or on a form containing equivalent information. Note: Owners or operators of stabilization ponds or lagoon systems may obtain the variance application form from the offices of the department of natural resources, bureau of watershed management at 101 South Webster Street, P.O. Box 7921, Madison, Wisconsin 53707. The form will provide guidance on the type of information needed to demonstrate widespread social and economic impacts.
(b) The application shall, at a minimum, include the following information: 1. Information required by s. NR 200.22, except for the information in s. NR 200.22(1) (e) 6.2. A statement that the permittee is seeking a variance pursuant to this section and s. 283.15(4) (a) 1 f., Stats.3. Information on the number and volume of lagoon or pond treatment cells, treatment processes, discharge periods, retention times, population served, influent flow, and available capacity for holding wastewater.4. Other information requested by the department that is relevant to the review conducted under sub. (3). Note: It is recommended that the permittee ask for calculation of potential phosphorus water quality based limits at least 12 months prior to permit expiration. This information will help the permittee complete their variance request portion of the permit application which is due 180 days prior to permit expiration.
(3) DEPARTMENT REVIEW. (a) The department shall review the submitted application for the variance and determine whether the permittee can achieve the phosphorus effluent limitations calculated pursuant to s. NR 217.13 with out widespread adverse social and economic impacts. In making this determination, the department shall: 1. Compare the calculated phosphorus effluent limitations to the phosphorus effluent data submitted under sub. (2). If the permittee does not have sufficient phosphorus discharge data for its system, the department may augment the data set with effluent data from a similar lagoon or pond system in the state to make the comparison. The department may apply statistical methodologies to make its determination on the ability of the current lagoon or stabilization pond system to meet phosphorus limitations.2. Evaluate the financial affordability analysis submitted by the permittee in response to the variance application requirement in s. NR 200.22(1) (p). Note: The department may use a US EPA publication titled, Interim Economic Guidance for Water Quality Standards - Workbook, EPA-823-B-95-002, March 1995, which provides information on evaluating economic and social impacts.
(b) The department's decision to approve or deny a variance under this section shall be made on or before the date of the s. 283.53(3) (d), Stats., public notice for the proposed permit reissuance and shall be made in accordance with the following: 1. If the department determines that the permittee cannot meet the phosphorus water quality based effluent limitation without widespread adverse social and economic impacts, the department shall approve the variance. If the variance is approved, the department shall specify in the permit that the variance has been granted for phosphorus, and the requirements in sub. (4) shall also be included in the permit.2. If the department determines that the permittee can meet the phosphorus effluent limitations without widespread adverse social and economic impacts or that effluent limitations are not necessary as determined by s. NR 217.15, the department shall deny the variance and notify the applicant of this determination in writing.(c) If the department denies a variance under this section, a permittee may not apply again after the permit is issued for a variance from the phosphorus water quality standard based on the factor in s. 283.15(4) (a) 1 f., Stats., for the same permit term.(d) A permittee may seek a variance from a phosphorus limit in a reissued WPDES permit based on the factors in s. 283.15(4) (a) 1 a. to e., Stats., and using the procedures and requirements in s. 283.15, Stats., and ch. NR 200. Note: All variances are subject to US EPA review and approval.
(4) PERMIT TERMS IF VARIANCE IS APPROVED. If the department approves a variance to the phosphorus effluent limitations under this section, the following requirements shall be included in the reissued permit: (a) The permit shall include a phosphorus variance effluent limitation as follows: 1. The numeric limitation shall equal the upper 99th percentile of representative daily discharge concentrations (one-day P99) as calculated in s. NR 106.05(5) (a).2. The variance limitation shall be expressed as a daily maximum concentration.(b) The permittee shall conduct monitoring of phosphorus during discharge periods at a frequency specified in the permit.(c) The permittee shall, to the extent practicable, identify and minimize the non-domestic sources of phosphorus to the system and operate the treatment system to minimize exceedances of the calculated limits.(d) The permittee shall investigate treatment technologies, process changes, pollutant source reduction steps, wastewater reuse or other techniques that may result in compliance by the permittee with the applicable phosphorus water quality standard, and shall submit reports on those investigations as required by the department.(5) CONTINUED VARIANCES. If a permittee received approval for a variance to the phosphorus standard under this section in a reissued permit, the permittee may request a continued variance from the phosphorus standard in a subsequent reissued permit pursuant to the procedures and requirements in this section.Wis. Admin. Code Department of Natural Resources NR 217.19
CR 10-035: cr. Register November 2010 No. 659, eff. 12-1-10; correction in (3) (a) 2. made under s. 13.92(4) (b) 7, Stats., Register January 2011 No. 661.