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dissolved and suspended solids in adjacent streams. Water quality of surface runoff <br />from the disturbed area is controlled by NPDES discharge limitations. Infrequent <br />discharges from the Bear sediment ponds must meet receiving stream standards and, <br />therefore, not degrade surface water resources. <br />In June, 1995, personnel at the Bear Coal Company discovered inflow to the 3rd <br />West Section of the Bear No. 3 Mine. The inflow was measured at approximately <br />18 gpm. During 1996, water reportedly continued to flow from the 3rd West seals <br />and also began flowing from the bleeder seals in the 2nd west Section. In <br />November, 1996, Bear Coal Company permanently ceased all mining operations at <br />the Bear No. 3 Mine and sealed the three existing portals. Since that time, no <br />additional information has been obtained concerning the source or rate of mine <br />intow to the Bear No. 3 Mine. There has been no recorded discharge from the Beaz <br />No. 3 Mine. <br />Groundwater quantity and quality in the alluvial material underlying the Bear No. 3 <br />facilities are closely related to water quality and flow of the adjacent North Fork of <br />[he Gunnison River. Groundwater flow in the alluvial material is controlled by the <br />water level and gradient of the North Fork of the Gunnison River. Water levels in <br />the alluvial material are generally 5.0 to 8.0 feet below the land surface. <br />Disturbance of the alluvial material is not expected to significantly reduce the <br />quantity of water present in [he alluvial material underlying the facilities area. Some <br />degradation of the quality of water in the alluvial material is evident based on field <br />conductivity and laboratory analyses of water samples taken from two on-site alluvial <br />groundwater monitoring wells (wells AA1 and AA3). Over time, the concentration <br />of total dissolved solids has increased significantly in downgradient monitoring well <br />AA1. Water samples obtained from well AA1, from 1987 through 1992, show <br />elevated levels of certain constituents including boron, calcium, chloride, fluoride, <br />magnesium, nitrate, potassium, sodium, and sulfate compared to water samples <br />analyzed from well AA 1 prior to 1986 and compared to water samples analyzed from <br />well AA3 which is upstream of the facilities area. The likely source of this <br />contamination is the coal stockpile, which was formerly located upgradient of well <br />AA 1. <br />Section 2.05.6(3) of the Bear No. 3 permit application presents an analysis of the <br />flow through the alluvium based on two scenarios. The first is total flow based upon <br />the total width of the alluvial deposit which is 500 feet. The second is the flow <br />which is subject to contamination by the coal stockpile which encompasses an area <br />only 150 feet wide. The flow through the alluvium is calculated using Darcy's Law <br />and assuming approximate hydraulic conductivity and gradient values as follows: <br />Q = kia = ka(h/1) where; <br />Q =flow in CFS <br />k =hydraulic conductivity = 0.00194 ft/sec <br />33 <br />