(a) The operator of any diversion or impoundment or any person who proposes to construct a diversion or impoundment may petition the Commissioner at any time for an exemption or variance for any such structure from the minimum flow and freshet release standards of these regulations. The petition shall contain information sufficient to allow the Commissioner to give adequate consideration to the effect, in terms of the factors enumerated below, of the operation of the structure under such an exemption or variance on the stocked river or stream system in question. The Commissioner may require additional information prior to acting on such a petition. Notice of the granting of an exemption or a variance shall be published in a newspaper of general circulation in the municipality or municipalities wherein the affected structure or river or stream system is located. In determining whether to grant an exemption or variance under this section, upon receipt of a petition from the operator of an impoundment or diversion, the Commissioner shall include, but is not limited to, consideration of whether operation of the structure will:
(1) Prevent the maintenance of viable pools, channels, or other water basins, or allow their undue depletion by normal evaporation and aquifer absorption;(2) Reduce oxygen content below minimal levels, cause stagnation, or inhibit reproductive cycles (where that potential exists);(3) Prevent the preservation, protection and safe maintenance of the river and stream stocking program, the natural aquatic life contained in such waters (including anadromous fish), and the natural or stocked wildlife dependent upon the flow of such water, and the availability of such water for public recreational uses; or(4) Meet the needs and requirements for public health, flood control, industry, public utilities, water supply, water quality, electric power production, public safety, agriculture, and other lawful uses of such waters. Any such exemption or variance may be revoked, after a hearing at which the operator shall have an opportunity to present evidence in support of retention of the exemption or variance, if the Commissioner finds, upon consideration of the factors enumerated above in this section, that there exists a change in the conditions surrounding, or manner of operation of, the diversion or impoundment, sufficient to materially and adversely alter the circumstances under which such exemption or variance was granted.