2015-05-11_INSPECTION - C1981018 (2)

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According to Section IV of the approved permit, sediment control measures at Deserado's SAE drill pads are based upon SEDCAD demonstrations that runoff volume and settleable solids will not exceed effluent limitations. The primary sediment control measures in place at the SAE areas observed included surface roughening, vegetative filtration, gradient minimization and, in limited cases with steeper slopes, earthen berms with rock check dams and geotextile fencing. These measures, as applied, appeared to be effective and in accordance with 4.05.5, since no erosional features or offsite sedimentation was observed. Topsoil (Rule 4.06 The Team evaluated topsoil salvage and protection measures at GVB locations to determine compliance with 4.06 and applicable permit requirements. According to Section V of the approved permit, the topsoil at Deserado mine is generally dry, with salinity issues in some areas, low fertility, and little organic matter. At the active GVBs observed, topsoil had been salvaged in combination with vegetative matter to aid in stockpile stability; segregated; and properly marked. Revegetation of the small stockpiles was generally limited to small patches of grass, but noxious weeds were not present and the piles had not suffered any apparent wind or water erosion. Remnant vegetative material salvaged along with the topsoil appears to be the primary stabilizing factor on these small short -lived stockpiles (GVBs are typically reclaimed within 2 or 3 years). The approved permit does not specifically address the issue of topsoil stockpile protection measures at these short-lived SAEs. Section V, Mine Surface Facilities Reclamation Plan, indicates that trees and large brush are removed prior to topsoil salvage but that grass, weeds, and small brush are incorporated into the topsoil during salvage. The permit states that this is to prevent over- compaction and to add organic material to the stockpiled topsoil. BME is clearly relying on salvaged small vegetation for topsoil protection. DRMS inspectors are aware of this practice and have not encountered erosion or loss of topsoil at SAE locations during routine inspections. Permit Section IV, Operations Plan, indicates that larger, longer -lived topsoil and subsoil stockpiles will be roughened, furrowed on the contour, seeded, and sediment ditches will be constructed around the bases of the piles. This language pertains to stockpiles at the sanitary landfill and coal refuse disposal site. Small, short-term topsoil stockpiles at SAEs are apparently handled differently than the larger longer -term stockpiles without explicit details in the permit. Colorado Rule 4.06.3(2)(a)(ii) allows the Division to approve other methods (than effective cover of quick - growing annual and perennial plants seeded during the first appropriate growing season) after a demonstration that those methods would provide equal protection. Although no erosional features were noted, this alternative topsoil stockpile protection measure must be expressly demonstrated to be protective of topsoil resources and approved in the permit under Rule 4.06.3(2)(a)(ii). Through email correspondence subsequent to this inspection, ...... ......... .... 4 1 P a g e