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• 2.06 The DMG, through its adequacy comments, has indicated the mine operation could possibly raise salinity levels in the Colorado River Drainage Basin. The means of which, originates from spring snowmelt and precipitation-related percolation through the site disturbance to the alluvial valley floor and the North Fork of the Gunnison River. Investigations done by Terror Creek Coal Company on the site of the Terror Creek Loadout (approximately 700 feet down gradient of the truck loadout area, and built on the same colluvial material) determined that little or no groundwater occurs in the colluvial material (ref. TCC permit page 2.04-3R). TCC performed tests, in March and April of 1994, on the colluvial material which forms a foundation base for its coal stockpile. The tests indicated that the colluvial material below the coal pad had not been significantly degraded by percolation from precipitation through the coal stockpile and the disturbed colluvial material (ref. TCC permit page 2.05-8c). This would indicate that the event postulated by the DMG, although theoretically sound, does not occur as speculated. • Drilling in the vicinity of the coal waste stockpile, coordinated by WESTEC in 1995, found no groundwater. Five holes where drilled during the geotechnical study, all within the colluvial material, and two into the Mancos shale formation. The two drilled into the Mancos Shale required a drilling fluid. A piezometer was placed in one of these holes and measured weeks later. From this measurement, of water 27 feet below ground surface, WESTEC suggests that the water level still indicates drilling water rather than groundwater. During August, 1996, the applicant drilled an additional hole in the vicinity of the proposed silo to evaluate foundation design concerns. The hole was drilled 120-feet deep. It did not encounter any water and it did not hit bedrock. • 7~-0 1 2.06 - 3 - sn 2/s7