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Prior to mining Phase 1, a sediment pond of approximately 1.0 acre in size will be excavated on the east central part of the permit area, as shown on Map C-2. A depression will be cut from the exist- ing terrain to an average depth of 4', therefore, a volume of 4.0 acre feet will be excavated. The northern portion of this silty overburden will be tested for contamination according to the Contin- gency Plan. If it is contaminated, it will be brought to two designated azeas north of the staging azea for land farming, as agreed to by the CDPHE and as shown on Map C-2. The overburden will be tested on site using portable TPH (total petroleum hydrocarbon) meters to detect the presence of contamination. All azeas will be flagged or mazked for removal to the farming azea or the staging area. Fruita Mazketing and Management and the CDPHE will handle the land farming of all over- burden moved from the site. Since this material will never be brought back to the mine site, it will not be part of the mine permit azea. It will be placed in the staging azea, as explained above. It is expected that 3.5 ac ft of the 4.0 ac ft excavated will be clean and can be placed in the staging area. Details of the pond design aze given in the Section 8 of this mine plan discussion. The sediment pond will have a gated steel dischazge structure that can be easily shut to keep the water in the pond in case any contaminated water from the refinery is found. Therefore, in order to cover the staging area with 2.8 feet of overburden, the total volume needed is 13.5 ac x 3.0 ft = 37.8 ac ft. - 3.5 ac ft (from sed pond) = 34.3 ac ft from Phase 1 and from Phase 2. Since much of the Phase 1 azea was previously excavated to make an evaporation pond, the top of the gravel was reached in some places but sediment has partially filled the pond over many yeazs. For this reason, the average silty overburden to be removed from Phase 1 is 2.5 feet. This is a vol- ume of 2.5' x 12.6 ac = 31.5 ac ft. Therefore, the amount needed to complete the filling of the stag- ing azea is 34.3 ac ft - 31.5 ac ft = 2.8 ac ft. This amount will be obtained from the clean overburden portion of Phase 2 prior to any mining in any phase. This portion is the southwest corner of the phase, which is approximately 1.4 acres x 2.5 ft depth = 3.5 ac ft, which is more than the 2.8 ac ft needed to complete the covering of the staging azea. Once the staging area has been covered and the fill has been compacted, Trenches 1 and 2 will be installed. Gilsonite Pit 9/03