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The sediment ponds receiving runoff from the proposed release area (Ponds 002, PECOCO and <br />004) have all been proposed as permanent ponds; the operator demonstrated that the quantity <br />and quality of impounded water were appropriate for their intended use. <br />In addition to the pond effluent sample data submitted by SSC, the Division requested annual <br />sediment level data from Peabody Sage Creek Mining, LLC for the ponds (Table 4). The data <br />for Pond 004 show that sediment levels in the pond have stabilized since revegetation activities <br />began in 2003. Detailed data for the PECOCO and Pond 002 impoundments were not available <br />due to surveying errors. None of the three sediment ponds treating runoff from the reclaimed <br />area have required cleaning or been cleaned since reclamation activities were completed. <br />Table 4 — Sediment Data Collected by Seneca Coal Company <br />Sediment Trends <br />(ac -ft gained /lost by year) <br />Pond <br />ID <br />2005 <br />2006 <br />2008 <br />2010 <br />004 <br />0.0 <br />0.1 <br />-0.1 <br />0.0 <br />The Division also independently completed a Revised Universal Soil Loss Equation (RUSLE) <br />calculation comparing the reclaimed areas to the adjacent undisturbed areas. The Division's <br />calculation was based on data in the permit application package for climate, soil types and <br />control/practice factors; slope measurements from the existing topography maps submitted <br />annually by PSCM; and vegetation monitoring data from the PSCM SL -01 application for the <br />Phase II bond release and Extended Reference areas. Several slopes in the reclamation area <br />were individually modeled and then averaged and compared to a weighted average of the <br />extended reference areas. The calculations, presented in Table 5, indicate that sediment delivery <br />from the mined areas is approximately equal to that of the adjacent undisturbed areas. <br />Table 5 — Sediment Data Provided by Peabody Sage Creek Mining <br />Area* <br />A <br />R <br />K <br />LS <br />C <br />P <br />Adjacent to <br />Landfill <br />0.07333 <br />30 <br />0.24 <br />0.97 <br />0.025 <br />.42 <br />Wadge /Landfill <br />Roadway <br />0.05594 <br />30 <br />0.24 <br />0.74 <br />0.025 <br />.42 <br />Peabody Sage Creek Mine Page 12 July 22, 2013 <br />Phase 11 Bond Release <br />