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3.1.7 Discharge from the Ground-Water System <br /> Prior to mining, ground water ischarged from the bedrock flow system via springs and seeps <br /> in the major drainages. The overall ground-water discharge rate in the Cement Creek watershed <br /> and Eureka Gulch was probably very close to the overall recharge rate. <br /> The base flow of the master stream in a watershed equals the total ground-water discharge to <br /> the watershed, minus evapotranspiration along creeks and near springs. The base flow of the <br /> North Fork of Cement Creek just above Gladstone is presently 230,000 gallons per day (gpd). <br /> According to SJCMV records the base flow of Eureka Creek below the Terry Tunnel is <br /> presently somewhat greater than 170,000 gpd (170,000 gpd plus the flow from McCarty Basin). <br /> Dewatering of the Sunnyside Mine may have reduced the flow of some springs and seeps along <br /> Cement Creek by reducing the hydraulic gradient toward the springs. Thus, the pre-mine <br /> ground-water discharge along Cement Creek was probably significantly greater than today. The <br /> recharge estimate of 8.5 inche (Section 3.1.6} indicates that the total pre-mine ground-water <br /> discharge should have been app oximately 4 1/2 times greater. However, the minimum recharge <br /> estimate would match present observed flows. <br /> 3.2 Pre-Mining Surface-W iter Hydrology <br /> 3.2.1 Surface-Water F ow <br /> Surface water in the area occu s in small mountain lakes and as stream flow in the drainages. <br /> Stream flow varies considerably. High flow rates occur during the spring in response to melting <br /> sanjuan\sunny\110361\oct9I.Rpt 28 <br /> e 0 snon ,, u��o� ��n <br /> �� <br />