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~e~inient pupas at pits 1, ~, ;;, and 4 ooviously are not constructedi it epnemeral water courses, a_no fol]uwing final reclamation ana oackfillinc ' of collection ditches it is questionable whetner surface runoff would maintain an adequate supply of water in the pond. 7ne proposed sediment pond at pit 8 is within 4UU feet of an existing stock pond. 1. Tne applicant snoulo provide a discussion demonstrating that tn. use of water from these impoundments would be in compliance witr~ ' State La,;. Z For eacn pond to De left as a permanent impoundment, the applicant must provide a detailed design plan prepared oy, or under the ' direction of, znd certified oy a qualified registered professional engineer. The Alan must si+ow• that the pond would meet th° appropriate design Standards of Rule 4.u~.9(1) e ana tnat any permanent diversions associated with the pond would meet the standards of Rule 4.05_3. The plan should specifically identify any renovation required to convert the sediment pond or ditches to the standards for permanent impoundments and ditches. 3. For each permanent impoundment, the applicant should provide sufficient hydrologic analysis to sho+v that water levels would be ' sufficiently stable to support their intended use. It is uncertain if stock ponds located high on the hillsides would receive sufficient runoff to accumulate water. ' 4. The water quality for ponds receiving only surface runoff should be sufficient for stock water use. However, ponds receiving water ' that has passed through the spoil nay not have a suitable water quality. For any permanent impoundment that would receive spoil water (either becuase the pond is in contact with the bottom of the pit and would receive unsaturated flow or because tfie spoil would develop an aquifer and the pond would intersect the post-mining spoil water levels), the applicant should provide, water.~uality predictions demonstrating the suitability of the water for stock water use. ' ~ Sediment Ponds 1. Sediment ponds at Pits 1, 2, 3, and 4 are located on hill slopes, and as a result, discharge could potentially result in significant erosion if not properly controlled. Rule 4.05.7 requires that i discharge be controlled by energy dissipators where necessary to reduce erosion and minimize disturbance to the Hydrologic balance. To date, ponds at pits 1, 2, and 3 have not discharged. Pond sizing calculations have not been submitted for these ponds and it may be tnat the ponds are of sufficient volume to contain the entire runoff from the 25 year, 2k Hour event. r+s previously approved existing structures they may oe acceptaole. However, ' design dra~vings and certification that the ponds have peen constructed as designed (Rule 4.05.6(7)) must be included in the permanent program permit application.