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WATER INFORMATION EXHIBIT G <br />1. Surface Water General Discussion <br />Water is not a significant issue with this operation since all mining will be dry in nature, the area is <br />well above the 100 year floodplain of the White River and no important drainages are in proximity <br />of the operation. An unnamed drainage located north of the property does drain to a reservoir located <br />immediately north of the permit area. This reservoir was installed by the landowners for <br />enhancement of grazing and is somewhat unique in the sense that no real discharge structure is <br />present. However, the capacity of the reservoir is greater than the volume delivered for the 100 year <br />event, therefore, it should not be a problem for the operation. People familiar with the reservoir have <br />said that the highest level that has been seen in the reservoir in the past 20 years is approximately <br />half the elevation of the road embankment (downstream dam). This is approximately 1/3 of the <br />storage volume of the reservoir. There has never been a problem with the road embankment. <br />Demonstration of Adequate Reservoir size <br />The drainage area above the lake is approximately 0.5 square miles of sagebrush terrain with some <br />herbaceous cover. The curve number for the area is estimated to be CN 79. The 100 year 24 hour <br />event for the area is 2.4 inches (from Tr -55). Therefore, the runoff from the event is 0.77 inches x <br />320 acres = 894,400 cubic feet. <br />A computer analysis was made of the topographic map of the reservoir at a contour interval of 1 foot <br />using Survcadd engineering software, which resulted in the following: <br />Volume Report 03/02/2002 <br />Comparing Grid file: E:/berrypit/reservoir.grd <br />Plane elevation: 6355.00 <br />Grid corner locations: 11565.93,10598.01 to 12959.50,11932.27 <br />Grid resolution X: 250, Y: 250 Grid cell size X: 5.57, Y: 5.34 <br />Area in Cut : 1820.8 sq ft, 0.042 acres <br />Berry Pit 3/02 21 <br />