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stability according to the rill and gully plan in Tab 22. When the channels were <br />stabilized, the non - riprapped segments were topsoiled and vegetated. <br />Seneca Coal Company has permitted permanent and temporary stock pond <br />impoundments in both the reclaimed drainage channels at the Seneca II -W Mine and <br />some existing culvert outlets. The stock ponds will slow the peak runoff of <br />precipitation events and help to minimize erosion in the drainage channels. They <br />will also act as additional alternate sediment control measures, minimizing the <br />potential for sediment from roads to be carried off the permit site. These small <br />ponds will benefit both livestock grazing and wildlife utilization of the reclamation. <br />Required information regarding stock pond construction, including stability analysis <br />documentation based on worst case embankment geometry assumptions, was <br />incorporated into the application by TR -48 and PR -4 amendments. Additional <br />information related to pre- construction design for individual stock ponds and <br />professional engineer certification of stock ponds following construction was <br />incorporated into the permit by PR -5. <br />Several of the stock ponds have been proposed as permanent impoundments, and the <br />impoundments would appear to be warranted to facilitate postmine livestock grazing <br />and wildlife use. However, documentation required by Rule 4.05.9(13) has not <br />been provided to allow for approval of any stock ponds as permanent <br />impoundments. The following commitment is included in Permit Tab 13, page 5, <br />regarding permanent impoundment demonstration of compliance: <br />Permanent impoundments will be reevaluated prior to bond release and <br />remedial construction performed to satisfy the appropriate sections of the <br />regulations. Prior to submittal of a bond release request, SCC will submit a <br />complete technical revision demonstrating that each permanent impoundment <br />meets the requirements of 4.05.9(13). <br />C. Sedimentation Ponds <br />Seneca Coal Company will primarily use sediment ponds to prevent additional <br />contributions of sediment to streamflow or runoff outside the permit area due to <br />mining disturbance. Existing sediment ponds include 005, 006, 009, 015, 016, and <br />017. All sediment ponds that have been approved have been constructed. <br />Information regarding design of ponds and diversions is provided in Tab 13 of the <br />permit application. <br />Pond 005 was permitted as a permanent impoundment that treats runoff from 285.6 <br />disturbed acres which drain to Dry Creek. <br />Pond 006 was permitted as a permanent impoundment that is located in a watershed <br />that is tributary to Hubberson Gulch. The pond was constructed in five separate <br />Seneca II -W Findings Document 21 C- 1982 -057 <br />Permit Revision No. 6 January 6, 2012 <br />