75-5-312. Temporary water quality standards. (1) The board may on its own, upon recommendation of the department, or upon a petition for rulemaking by a person, including a permit applicant or permittee, temporarily modify a water quality standard for a specific water body or segment on a parameter-by-parameter basis in those instances in which substantive information indicates that the water body or segment is not supporting its designated uses. When the board adopts temporary standards, the goal is to improve water quality to the point at which an additional beneficial use or uses are supported.
     (2) As a condition for establishing temporary water quality standards for a particular water body or segment, the department or the petitioner, as applicable, shall prepare a support document and implementation plan for use by the board in determining whether to adopt a proposed temporary water quality standard.
     (3) If a person petitions for rulemaking under this section, the petition must specifically describe the affected state water, the existing ambient water quality for the parameter or parameters at issue, the water quality standard or standards affected, and the temporary modifications sought. Within 180 days after the board grants a petition to initiate rulemaking, the petitioner shall prepare and submit to the board and the department a proposed support document and implementation plan that sets forth:
     (a) the water quality limiting factors affecting the water body or segment;
     (b) the existing beneficial use or uses and the beneficial use or uses considered attainable in the absence of the water quality limiting factors;
     (c) an implementation plan to eliminate the water quality limiting factors to the extent considered achievable; and
     (d) a schedule for implementing the plan that ensures that the water quality standards for the parameter or parameters at issue are met as soon as reasonably practicable and in no event later than the time allowed by the board in the temporary standard.
     (4) Upon the board's adoption of a temporary water quality standard, the department shall ensure that reasonable conditions and limitations designed to achieve compliance with the implementation plan are established in appropriate discharge permits.
     (5) (a) A temporary modification of a water quality standard may not result in adverse impacts to existing beneficial uses or be established for a total period longer than 20 years.
     (b) During the period of the temporary modification, the board may not allow a discharge that will cause overall water quality to become worse than the overall quality of the water body or segment prior to the discharge.
     (6) If a state water is designated as having temporary standards, the department shall report to the board at least every 3 years or upon request of the board regarding whether adequate efforts have been made to implement the plans submitted as the basis for the temporary standard.
     (7) The board shall review temporary standards at least every 3 years at a public hearing for which notice and an opportunity for comment have been provided. The board may terminate the temporary standard based on information submitted at the time of its review that the applicant is not complying with the approved implementation plan.
     (8) The board shall terminate a temporary standard for a parameter if:
     (a) values for the modified parameter or parameters improve to conditions that support all designated uses for that classification;
     (b) the state water for which the temporary standard is adopted is reclassified as provided for in 75-5-302; or
     (c) the plan submitted in support of the temporary water quality standard is not being implemented according to the plan's schedule or modifications to that schedule made by the board or department.
     (9) The board may modify the plan if the permittee submits convincing evidence to the board that the plan needs modification. The board may not extend the plan beyond a total period of 20 years.
     (10) If a temporary standard for a parameter in a particular state water is terminated because the plan submitted in support of the temporary water quality standard is not being implemented according to the plan's schedule or modifications to that schedule made by the board or department, a person may request a new temporary standard by submitting both a petition for rulemaking and a plan that meet the requirements of subsections (2) and (3). However, the board may not adopt another temporary standard for the parameter in the state water that would cumulatively be in effect for a total period longer than 20 years for the parameter in the state water.

     History: En. Sec. 3, Ch. 539, L. 1995.