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Ground water will not be encountered. Removal of the mine waste material is expected to <br /> improve ground and surface water quality. Surface water impacts will be controlled through <br /> implementation of our Stormwater Management best management practices. <br /> A Stormwater management Plan (SWMP) has been designed specifically for this operation and <br /> a permit has been applied for with the Colorado Water Quality Control Division. A copy of the <br /> Stormwater Management Plan is available. <br /> Stormwater Management controls could include using silt fences and/or straw bales during <br /> removal to the mine waste. <br /> Hydrologic Data <br /> North Clear Creek is the significant watershed of this vicinity and it bears approx. 4.0 miles to <br /> the east and 1,800' in elevation below the Affected Area. Drainage from this watershed area <br /> follows down Russell Gulch to North Clear Creek. <br /> There are limited perched zones and no traditionally defined aquifers in this mountainous area. <br /> The site is completely composed of crystalline Precambrian rocks, i.e. gneisses and schists, and <br /> tertiary intrusive rocks such as quartz monzonites overlain by 0-24"of unconsolidated material. <br /> Ground water wells within one-quarter mile of site boundary are detailed in a map attached at <br /> the end of this Exhibit C, sourced from the Colorado Division of Water Resources. It shall also <br /> be noted that the groundwater in this area is unclassified per the Colorado Division of Water <br /> Resources and is primarily considered surface water recharge. <br /> Unconsolidated materials, soils, of between 0 and 24" overlay the crystalline rocks. The rocks <br /> themselves have essentially no porosity or permeability. Random, in-identifiable fractures due <br /> to jointing and faulting provide the only groundwater transmissivity and relative porosity. The <br /> site is underlain by numerous mine openings,the most important of which is the workings of <br /> the Old Town Mine (mine complex immediately adjacent to the east). This mine's workings <br /> effectively drain the area underneath the site, connecting the Old Town to the Argo Tunnel via <br /> the Hot Time Lateral. Refer to a map from USGS Professional Paper 359, ECONOMIC <br /> GEOLOGY OF THE CENTRAL CITY DISTRICT GILPIN COUNTY COLORADO, Sims, <br /> P. K. Drake, A. A., and Tooker, E. W., 1963. <br /> Hydraulic conductivity for the undisturbed rock types present at the site, in-situ before mining, <br /> ranges from 10-2— 10+2 gallons per day per square foot (as reported by Freeze and Cherry <br /> (1979)) due to joints and fractures in the rock. The existence of the underground mine workings <br /> provide a direct hydraulic conduit for groundwater beneath the site. <br /> As previously stated, the Argo Tunnel is within the vicinity beneath the proposed Affected Area <br /> at a depth of approximately 1,500 feet. The condition of the existing ground water is <br /> significantly worse than the SPLP lab analysis of leachate from the abandoned mine dump <br /> 34 <br />