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Although the pit will contain all runoff for any possible runoff event, the existing pit is covered <br />by an NPDES permit number COG-500549 for dischazges associated with storm water. This <br />covers any storm water discharges associated with any part of the site such as topsoil berms, <br />roads, etc. <br />The expansion mining area will be mined from the east to the west, constantly maintaining a <br />gradient of the disturbed area toward the existing pit, therefore, there is no need for sediment <br />control ditches or sumps on the east side of the expansion azea. An existing dirt road is the <br />eastern edge of the disturbed area. A small gully immediately east of this road which drains to <br />the north will not be affected by the operation. <br />2. Ground Water General Discussion <br />A separation exists between the lowest elevation in the extraction azea and the ground water. As <br />determined by previous studies submitted with the 1999 Amendment, all visible water at the pit <br />bottom is due to surface runoff from irrigation, precipitation, and snow melt. No groundwater <br />has been encountered in the pit to January 2007. The 2007 Amendment will not mine any deeper <br />than past mining and no groundwater is expected to be encountered for the life of the operation. <br />3. Water Consumption <br />All water used by the operation is provided by the permitted well to the north of the pit. This <br />well and right is adjudicated for industrial use with the pit. A copy of the well permit is included <br />with this section. The well pumps from the shallow alluvial water neaz the creek. It is then <br />piped to two water tanks located neaz the concrete plant. This water was previously stored in an <br />open pond, but it was decided that buried tanks would not only be easier from an operational <br />standpoint, but they also conserve a good deal of water previously lost through evaporation and <br />infiltration. Approximate consumptive use calculations are shown below for the operation: <br />Vagneur Pit June 07 G-2 <br />