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No. 3 Mine sediment ponds must meet receiving stream standards and, therefore, not <br />degrade surface water resources. <br />In June, 1995, personnel at the Bear Coal Company discovered inflow to the 3rd West <br />Section of the Bear No. 3 Mine. The inflow was measured at approximately 18 gpm. <br />During 1996, water reportedly continued to flow from the 3rd West seals and also began <br />flowing from the bleeder seals in the 2nd west Section. In November, 1996, Bear Coal <br />Company permanently ceased all mining operations at the Bear No. 3 Mine and sealed the <br />three existing portals. Since that time, no additional information has been obtained <br />concerning the source or rate of mine inflow to the Bear No. 3 Mine. There has been no <br />recorded discharge from the Bear 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 the <br />Gunnison River. Groundwater flow in the alluvial material is controlled by the water level <br />and gradient of the North Fork of the Gunnison River. Water levels in the alluvial material <br />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 quantity of <br />water present in the alluvial material underlying the facilities area. Some degradation of <br />the quality of water in the alluvial material is evident based on field conductivity and <br />laboratory analyses of water samples taken from two on-site alluvial groundwater <br />monitoring wells (wells AA1 and AA3). Over time, the concentration of total dissolved <br />solids has increased significantly in downgradient monitoring well AA1. Water samples <br />obtained from well AAl, from 1987 through 1992, show elevated levels of certain <br />constituents including boron, calcium, chloride, fluoride, magnesium, nitrate, potassium, <br />sodium, and sulfate compared to water samples analyzed from well AAl prior to 1986 and <br />compared to water samples analyzed from well AA3 which is upstream of the facilities <br />area. There are two likely sources for the contamination of alluvial well AA1. The first <br />possible source of this contamination is the coal stockpile, which was formerly located <br />upgradient of well AA1. The second possible source is the spring that is located near the <br />pre-law Edwards Mine portal. <br />Adequate dilution of any effluent generated at the Bear No. 3 Mine will mitigate any <br />effects of reduced water quality in the Bear No. 3 alluvium on downstream AVFs. The <br />greater the distance from the Bear No. 3 Mine, the greater the dilution of any effluent. <br />The potential impacts are considered insignificant, and the applicant's groundwater and <br />surface monitoring program should detect any changes in the quantity and quality of <br />ground and surface water supplied to the North Fork of the Gunnison River and, therefore, <br />to alluvial valley floors downstream. <br />No potentially significant impacts to the AVF have been identified. The monitoring plan <br />outlined in the permit application will ensure that the essential hydrologic functions of the <br />AVF are maintained by monitoring the development of any effluent at the mine site. <br />XVIH. Operations on Prime Farmland <br />Prime farmland investigation information is located in Section 2.04.12 and 4.25 of the Bear No. <br />3 permit application. <br />27