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Law, the estimated flow into the trench from the surrounding alluvial aquifer is approximately 574 <br />gallons per minute (gpm). <br />In order to estimate drawdown resulting from the pit dewatering affects, the assumptions were <br />applied to the alluvial aquifer at the SerFer site. The mathematical approach developed from the <br />application of these assumptions can approximate the response of the alluvial aquifer near the site. <br />Among other aspects, the saturated alluvium near the site is fairly consistent in material and <br />thickness, the hydraulic gradient is very low, and the specific yield is high. <br />Additional simplifying assumptions were made in estimating the pit dewatering affects. Surface <br />recharge was also neglected since values would fluctuate considerably throughout the year. <br />The approach that was used to estimate the extent of drawdown from dewatering is referred to as <br />"flow to a drainage trench from a line source" and is referenced in Powers (1992). Results were <br />checked with additional approaches as presented in Freeze and Cherry (1979). Results indicate <br />that drawdown from pit dewatering will extend approximately 700 feet from the pit boundary. The <br />saturated thickness of the alluvial aquifer during dewatering is illustrated in Figure 1. <br />12 <br />m <br />10 - <br />ai 8 <br />c <br />Y <br />_V <br />t 6 f <br />H <br />W 4 <br />M <br />M 2 <br />E <br />0 <br />3 <br />Q 0 200 400 600 800 1,000 1,200 1,400 <br />Distance from Pit (feet) <br />Figure 1 <br />MONITORING AND REPORTING <br />The goal of the groundwater monitoring program is to measure groundwater elevations for use in <br />evaluating the baseline alluvial groundwater system and potential hydrologic changes resulting <br />from mining and dewatering operations. The purpose of these evaluations is to anticipate potential <br />impacts to surrounding landowners and respond to Mind Land Reclamation Board requirements. <br />To accomplish this goal, the monitoring prograrn includes the following components: <br />Connell Resources, Inc. I Serfer Pit Groundwater Monitoring Plan