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Disturbance of the alluvial material is not expected to significantly reduce the quantity of water present in the alluvial material underlying the facilities azea. Some degradation of the quality of water in the alluvial material is evident based on field conductivity and laboratory analyses of water samples taken from two on-site alluvial groundwater monitoring wells (wells AAl and AA3). Over time, the concentration of total dissolved solids has increased significantly in downgradient monitoring well AA1. Water samples obtained from well AA1, from 1987 through 1992, show elevated levels of certain constituents including boron, calcium, chloride, fluoride, magnesium, nitrate, potassium, sodium, and sulfate compared to water samples analyzed from well AA 1 prior to 1986 and compared to water samples analyzed from well AA3 which is upstream of the facilities area. There are two likely sources for the contamination of alluvial well AA1. The first possible source of this contamination is the coal stockpile, which was formerly located upgradient of well AAl. The second possible source is the spring that is located near the pre-law Edwards Mine portal. Adequate dilution of any effluent generated at the Bear No. 3 Mine will mitigate any effects of reduced water quality in the Bear No. 3 alluvium on downstream AVFs. The Beater the distance from the Bear No. 3 Mine, the greater the dilution of any effluent. The potential impacts are considered insignificant, and the applicant's groundwater and surface monitoring program should detect any changes in the quantity and quality of ground and surface water supplied to the North Fork of the Gunnison River and, therefore, to alluvial valley floors downstream. No potentially significant impacts to the AVF have been identified. The monitoring plan outlined in the permit application will ensure that the essential hydrologic functions of the AVF aze maintained by monitoring the development of any effluent at the Bear No. 3 Mine site. XVIII. Operations on Prime Farmland Prime farmland investigation information is located in Section 2.04.12 and 4.25 of the Beaz No. 3 permit application. No prime farmland exists within the permit area. The majority of the disturbed area has been historically affected by mining and has not been historically used as cropland. The Soil Conservation Service has indicated that no soils have been identified as prime farmland in Gunnison County, Colorado (SCS, USDA, 1980, Important Farmland Inventory - Colorado, Denver, Colorado). The Bear Coal operation is in compliance with the provisions ofthis section. XIX. Mountaintop Removal This section does not apply to the Bear Coal Company permit. 32