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Mr. Roy Karo <br />June 5, 2014 <br />Page 2 <br />SCC provided additional information. The Division reviewed the submitted information <br />and had the remaining concern. SCC provided pond capacity data as requested. <br />However, for some ponds (namely 005, 009, and 017) the capacities have declined <br />significantly in recent years, and further evaluation or explanation is necessary to show <br />that Phase 2 release of the area is justified despite these decreases in pond capacities. Is <br />there any other data related to pond capacities that indicates a trend of decreasing <br />sediment loading into the ponds? <br />b. Please provide an analysis, using a predictive model (SEDCAD or RUSLE), which <br />compares the suspended solids generated off the pre- mining land or comparable adjacent <br />areas, to the bond release area. <br />SCC response: SCC provided total sediment yield in lieu of suspended solid data for <br />pond 005 and pond 006. <br />Because the SEDCAD analyses for Pond 006 indicate that the post- mining sediment load <br />is somewhat higher than the pre- mining sediment load (and thus the sediment loading <br />requirement of Rule 3.03.1(3)(b) is not met), the Division requests that SCC provide a <br />comparison to an analysis of the worst -case scenario (or similar) for the Pond 006 area; <br />this could be the results of a new SEDCAD run or specific reference to existing <br />information in the Seneca IIW PAP. Also, the Division has observed that the sub - <br />watershed particle size distributions in the SEDCAD run for pre- mining conditions <br />contain many values of 0 %. It is possible that if non -zero (realistic) values were included <br />in these tables, then the results of pre- mining sediment loads might match post- mining <br />sediment loads. <br />The proposed decision date for SL5 is June 30, 2014. Please provide responses to item no. 9a. and 9b. in <br />advance of that date to allow the Division to review SCC's response prior to the proposed decision date. <br />Please call me if you have additional questions. <br />Sincerely, <br />d OW- <br />Janet H. Bums <br />Environmental Protection Specialist III <br />Janet.binnsnn state.co.us <br />CC: Scott Cowman, Seneca Coal Company <br />