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WATER INFORMATION EXHIBIT G <br />1. Surface Water General Discussion <br />The surface water flow of the original mining site on the flat terrace was toward the northwest <br />neaz the junction of Woody Creek and the Roaring Fork River. The eastern portion of the hillside <br />in the expansion area drains to an ephemeral stream that will not be disturbed as a result of the <br />mining operation. <br />The permit area is not prone to flooding from the adjoining properties. The lazgest drainage <br />course in the vicinity is Woody Creek, located adjacent to the northerly permit boundary. Gravel <br />extraction activities aze separated from the Woody Creek by an undisturbed ridge approximately <br />80 feet wide above the flow-line of the creek. The Roaring Fork River flows northerly <br />approximately 1000 feet west of the permit boundary. Mining is conducted in a manner that will <br />not increase the amount of surface storm water runoff above historic flows. Any storm runoff <br />entering the site will be captured within the pit azea and allowed to percolate into the ground. <br />The site is covered by a Pitkin County Water Protection Plan. This plan is included in Appendix <br />A. <br />The operation is not within the 100 year floodplains of the Roaring Fork River or Woody Creek <br />All water from the main disturbed area is captured in the pit, which is large enough to handle any <br />possible runoff event. Water that does run off into the pit is absorbed into the gravel and <br />becomes groundwater. The berm around the pit and the hillside to the east prevent any <br />undisturbed runoff from entering the pit. The bottom of the excavation of the pit will be <br />approximately 2 feet above the static groundwater table in order to ensure that groundwater is <br />not exposed through the mining of the pit. The pit is intended to be a dry pit and as such the pit <br />does not have a gravel well pemut or any other required water permits. <br />An engineering study was conducted by Allied Independent Consultants which showed that any <br />water standing at the lowest elevation in the pit area is surface runoff from precipitation and <br />irrigation waste water. This study is enclosed in Appendix C. <br />Vagneur Pit June 07 G-1 <br />