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1.SH:1V. See Map C-3 for a cross section of the trench details in relation to the staging area and the mining pit. As described in the Water Information section, this level will initially be kept low but can be modified up or down in response to what is being seen at the monitoring wells. The trench may have a ]ow spot in the furthest point of the southeast corner. If this is encountered, clean fill will be used to build up the embankment to the required level above the water, as shown on the Cross Section of Map C-3. This embankment portion will not be steeper than Z.SHI.OV. It will be built in lifts not to exceed 8" and will be compacted to 95% maximum dry density as tested with a standard Troxler densitome[er on site. The overburden material from the majority of the excavation of Trench #1 may need to be treated in the off site contaminated overburden farming area. This is also shown on Map C-2. The gravel should not be contaminated and will be placed in the staging area for processing. The overburden material from Trench #2 should not be contaminated and will be placed in the substitute soil stockpile area for later use in reclamation. The amounts of material excavated from each trench are listed below: Trench #1 Trench #2 TotalVolume (cy) Clean Overburden (cy) 933 3111 4044 Contaminated Overburden (cy) 5733 0 5733 Clean Gravel(cy) 16667 9955 26622 Totals 23334 13068 36399 These quantities are based on an average cross sectional area of the trench of 420 sq. ft., excavating to a depth of 4444' with a 6' bottom width. Overburden thickness are 3.0' and 2.5' for Trenches 1 and 2, respectively. It is assumed that 86% of the overburden from Trench #1 is contaminated. This is based on the CDPHE contaminated soil boundaries shown on-Maps C-1 and C-2. The procedures for hauling this material to the FMM fanning site and spreading the material out for treatment have Gilsoni[e Pit 1/04 10