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WATER INFORMATION EXHIBIT G <br />1. Surface Water General Discussion <br />The surface water features within and near the permit area are the Gunnison River which is <br />approximately 50 feet north of the permit boundary at the closest point, and ponds created by <br />gravel mining. FEMA has not published a 100 year flood plain for this stretch of the Gunnison <br />River. The excavation is located approximately 30 feet above the normal elevation of the river. <br />All surface water will be contained on site through the use of sediment ponds, diversion ditches <br />and reclamation islands which will work as catch benches. The surface water will be contained <br />from the disturbed area to prevent sediment from being transported of site. <br />2. Hydrology and Sediment Control for Mining <br />Water that is encountered in the pit will not be released from the site. The only water that will be <br />found within the disturbed area is stormwater runoff and water used in the wash plant. The <br />runoff that needs to be collected in the sediment pond is shown in the calculation below: <br />Runoff Curve Number and Runoff <br />14:26:45 2011 <br />Tue Jan 11 <br />Project: Craig Ranch Pit <br />O1/11/11 <br />Location: <br />Present <br />1. Runoff Curve Number (CN) <br />Cover description <br />Desert Shrub (Poor) <br />By: Ryan Ellis Date: <br />Checked: Date: <br />CN Soil Group Area(Sq.Ft.) <br />85 C 8712000.000 <br />CN (weighted): 85.0 <br />Total Area: 8712000.000 Sq.Ft. <br />2. Runoff <br />Return Period: 100-Year <br />Rainfall, P: 2.20 <br />Runoff, Q: 0.9446 <br />Runoff Volume: 15.7431 <br />in <br />in <br />Acre-Ft <br />Craig Ranch Pit, March 2011 G-1