Administrative Rules of Montana
Department 17 - ENVIRONMENTAL QUALITY
Chapter 17.24 - RECLAMATION
Subchapter 17.24.18 - Rules and Regulations Governing the Montana Strip and Underground Mine Siting Act
Rule 17.24.1820 - WATER QUALITY: DRAINAGE

(1) All surface water which might damage regraded slopes shall be intercepted on the uphill side of the slope or other mine site perimeters by diversion ditches and conveyed by stable channels or other means to natural or prepared watercourses outside the operation and it is determined by the department that such ditches and channels are unnecessary or would create a more serious pollution problem. Such conveyances shall be of sufficient size and grade to prevent overflow into the operations area. If the ditches are likely to carry surface water only intermittently, they shall be retopsoiled and revegetated with recommended grasses, forbs, and/or legumes. All constructed diversion ditches shall be included in the permit acreage and shown on the map.

(2) Water accumulating in the course of the operation shall meet the water quality specifications enumerated herein or shall be pumped or siphoned to a treatment or settling facility prior to discharge into a natural drainway. Under no circumstances shall water be discharged onto highly erodible soil banks.

(3) No surface drainage shall be discharged through or permitted to infiltrate into existing deep mine workings. Location of all known existing deep mines within the permit area and plans for remedial measures shall be included in the application for a permit.

(4) All drainage from the active construction area shall exit through impoundment or treatment facilities in accordance with (1) and (2) of this rule.