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the pre-mining slopes. The pre-mining and post-mining drainage areas of the reclaimed <br /> channels are similar in acreage and slope. After the watershed was graded and the <br /> location of the drainage channels determined, the channels were to be constructed to the <br /> required shape. Permanent channel construction including riprap installation (where <br /> specified) was completed within one year of completion of the final grading of adjacent <br /> backfill slopes, and prior to topsoiling of areas adjacent to the channel. Following <br /> construction, the channels were not topsoiled to allow for initial stabilization. Channels <br /> were inspected by DRMS for stability according to the rill and gully plan in Tab 22. <br /> When the channels stabilized, the non riprapped segments were topsoiled and vegetated. <br /> SPL has permitted permanent and temporary stock pond impoundments in both the <br /> reclaimed drainage channels at the Seneca IIW Mine and at some existing culvert outlets. <br /> The stock ponds slow the peak runoff of precipitation events and help to minimize <br /> erosion in drainage channels. They will also act as additional alternate sediment control <br /> measures,minimizing the potential for sediment from roads to be carried off the permit <br /> site. These small ponds will benefit both livestock grazing and wildlife utilization of the <br /> reclamation. Required information regarding stock pond construction, including stability <br /> analysis documentation based on worst case embankment geometry assumptions, was <br /> incorporated into the application by TR48 and PR4. Additional information related to <br /> pre-construction design for individual stock ponds and professional engineer certification <br /> of stock ponds following construction was incorporated into the permit by PR5. <br /> Several of the stock ponds have been proposed as permanent impoundments, and the <br /> impoundments are warranted to facilitate post-mine livestock grazing and wildlife use. <br /> Documentation required by Rule 4.05.9(13)has been provided to allow for approval of <br /> the stock ponds as permanent impoundments. The following commitment is included in <br /> Permit Tab 13, page 5,regarding permanent impoundment demonstrations of compliance: <br /> Permanent impoundments will be reevaluated prior to bond release and remedial <br /> construction performed to satisfy; the appropriate sections of the regulations. Prior <br /> to submittal of a bond release request, SCC will submit a complete technical <br /> revision demonstrating that each permanent impoundment meets the requirements of <br /> 4.05.9(13). <br /> C. Sedimentation Ponds <br /> SPL will primarily use sediment ponds to prevent additional contributions of sediment to <br /> streamflow or runoff outside the permit area due to mining disturbance. Sedimentation <br /> ponds are proposed and approved as permanent impoundments. The impoundments are <br /> warranted to facilitate post mine livestock grazing and wildlife use. Documentation <br /> required by Rule 4.05.9(13) has been provided for most of the ponds to allow for <br /> approval as permanent impoundments. The following commitment is included in Permit <br /> Tab 13, page 5, regarding permanent impoundment demonstration of compliance: <br /> Permanent impoundments will be reevaluated prior to bond release and remedial <br /> construction performed to satisfy the appropriate sections of the regulations. Prior <br /> to submittal of a bond release request, SCC will submit a complete technical <br /> revision demonstrating that each permanent impoundment meets the requirements of <br /> 4.05.9(13). <br /> Existing sediment ponds include 005, 006, 009, 015, 016, and 017. Information <br /> regarding design of ponds and diversions comprises Tab 13 of the permit application. <br /> Information regarding the requirements for permanent pond and stock pond approvals by the <br /> Colorado State Engineer's Office (Division of Water Resources) are found in Tab 20 <br /> Page 15 of 37 <br />