(1) A person may apply to the department for a nutrient standards variance at any time following the board's adoption of base numeric nutrient standards. In addition to this rule, variances are subject to the procedures and requirements contained in Department Circular DEQ-12B (May 2018 edition).

(2) An application for a general variance must provide information demonstrating that the wastewater treatment facility meets the requirements of Department Circular DEQ-12B (May 2018 edition). The decision to grant the general variance must be reflected in the permit that is made available for public comment.

(3) An application for an individual variance must adequately demonstrate that there are no reasonable alternatives that eliminate the need for a variance and that attainment of the base numeric nutrient standards is precluded due to economic impacts or limits of technology, or both. If the demonstration relies upon economic impacts, the department shall consider any guidance developed by the department and the nutrient work group, as provided in 75-5-313(2), MCA.

(4) The department may approve the adoption of an individual variance that specifies interim effluent limits different from those contained in general variance limits contained in Department Circular DEQ-12B (May 2018 edition), if water quality modeling demonstrates that greater emphasis on the reduction of one nutrient may achieve similar water quality and biological improvements as would the equal reduction of both nitrogen and phosphorus. The variance must provide effluent limits that reflect the lowest effluent concentration that is feasible based on achieving the highest attainable condition for the receiving water. A person shall submit the proposed effluent limits and supporting data in an application for an individual nutrient variance under (3). A person who has an individual variance with effluent limits that are based on this section shall, in each subsequent triennial review of those limits conducted pursuant to 75-5-313(7), MCA, collect and submit water quality data to demonstrate whether the biological status of the receiving water continues to justify those effluent limits.

(5) The department shall review each application for an individual variance to determine whether a reasonable alternative, such as trading, a permit compliance schedule, a general variance, reuse, recharge, or land application would eliminate the need for an individual variance. If the department makes a preliminary finding that a reasonable alternative to approving an individual variance is available, the department shall consult with the applicant prior to making a final decision to approve or deny the individual variance.

(6) If, after consultation with the applicant, the department determines that no reasonable alternative to an individual variance exists, the department shall determine whether the information provided by the applicant pursuant to (3) adequately demonstrates that attaining the base numeric nutrient standards is not feasible. If the department finds that attaining the base numeric nutrient standards is not feasible, the department shall approve an individual variance, which will become effective and incorporated into the applicant's permit only after adoption by the department in a formal rulemaking proceeding.

(7) A variance is not needed in situations where a person complies with the waste load allocation established in an approved TMDL.

(8) The department adopts and incorporates by reference Department Circular DEQ-12B, entitled "Nutrient Standards Variances" (May 2018 edition), which provides procedures and requirements for nutrient standards variances. Copies of Department Circular DEQ-12B are available at the Department of Environmental Quality, 1520 East 6th Avenue, P.O. Box 200901, Helena, MT 59620-0901.