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2. Surface Water <br /> All surface water flows that drain to the site currently pass across the meadow before draining to <br /> the West Fork of Clear Creek to the north. During mining,these flows will be partially <br /> intercepted by the mining activity as the operation progresses. All surface water runoff that <br /> reaches the disturbed area will be trapped within the mining pit and not allowed to discharge. <br /> The mining pit will contain all stockpiles and equipment. During most of the mine's life this will <br /> be accomplished by the fact that the entire mining area will be significantly (>40 feet) below <br /> baseline grade. The remaining deposit, during these middle years of mining,will act as a massive <br /> barrier to surface water discharge. All surface water that encounters the site will be allowed to <br /> evaporate or infiltrate. To handle stormwater of this type in an organized manner, sumps will be <br /> maintained within the site in areas that are not being actively mined, and the site will slope <br /> towards these sumps. <br /> In the latter years of mining, anticipated to be the final 2-3,the pit will begin approaching the <br /> West Fork of Clear Creek, with the natural material berm being mined out from within. A <br /> minimum six-foot-tall berm of this natural material will be maintained until all reclamation <br /> revegetation is completed behind it, to the south. This way there will always be a stormwater <br /> barrier onsite while there is disturbed mining area. During the removal of this berm material, <br /> short term sediment control tools such as silt fences and sediment control logs will be installed <br /> along the natural berms outslope toe. <br /> Topsoil windrows constructed from topsoil stripped in advance of mining will have a one foot <br /> deep ditch dug around them for stormwater collection. All of these windrows will be seeded <br /> within 15 days of construction. <br /> 3. Groundwater <br /> No groundwater is anticipated to be encountered during any phase of the operation. Mining will <br /> cease before the anticipated groundwater table is reached, which drilling has shown to be <br /> between 100-120 feet below the current topography. In the even that groundwater is exposed, <br /> DMR <br /> September 2018 G-2 <br />