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<br />• The drainage from the property will be routed to sediment ponds created by the mining. No adverse <br />impact to the surface water system is expected. <br />Ground Water Sy,Stem <br />The mining operation will be dewatered utilizing trenches surrounding the site. Ground water will be <br />dischazged from the trenches at a maximum rate of approximately 1500 gpm. The water will be <br />pumped into Boulder Creek and/or to the wash plant. The depth to the water table varies from three <br />to six feet, requiring drawdown in the alluvial aquifer of 10 to 13 ft. <br />A seazch of the State Engineer's records was made to locate wells within one mile of the site. A map <br />showing the well locations is included on Figure C-1, Exhibit C - Premining Plan. A tabulation of <br />the wells is included in this exhibit as Table G-1. The wells in the azea consist of three types; <br />domestic, livestock and gravel pits. <br />There are domestic wells within one mile of the site. The wells withdraw water from the alluvium or <br />the Laramie-Fox Hills aquifer. The azea is underlain by shales and sandstones of the Lazamie <br />Formation and Lazamie-Fox Hills aquifer. Shallow bedrock at the site consists of clay shale that <br />comprises part of the aquitard overlying the bedrock aquifer and mining operations aze not expected <br />to affect the bedrock aquifer. Boulder Creek should serve as a ground water divide. Therefore, no <br />alluvial ground water declines are expected west of the creek. <br />Water level declines are expected to occur in the vicinity of the operation to the south, east and nonh <br />of the mined azea. Although it is difficult to predict, based on previous experience we do not expect <br />water levels to be affected at distances greater than one-quarter mile. And at that distance water level <br />changes will be insignificant. <br />Within one-quarter mile, and east of the creek, there aze six alluvial wells, two gravel pits and four <br />domestic wells. One reclaimed gravel pit is located on the eastern boundary of the site. Another pit <br />is located south of the site. Four domestic wells are located east and northeast of the site. <br /> <br />19 <br />f(~~ <br />