1987-12-01_PERMIT FILE - C1981017 (176)

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ground water of Coal Creek. A geochemical analysis of the roof and floor rock and coal (see page III-D-37 of the permit applica- tion) failed to indicate any toxic or hazardous materials. In addition, seven years of ground and surface water monitoring, during which time similar wastes were being disposed of, indicate that water quality has not been materially damaged. Therefore, presently this potential impact is insignificant. The alluvial ground waters and surface waters will be monitored during and after mining to detect any further degradation of water quality if it occurs. The rock tunnel at the mine will be constructed in the Mancos Shale and proceed up the stratigraphic column until it intersects the Dutch Creek (M) coal seam. The tunnel has cut through the Cozzette and is now (6/86) cutting through the Rollins sandstones. • As a result, inflows of ground water from these potential P aquifers have entered the tunnel. The rates of inflow have been insigni- ficant. This is based on measurements of from 5 to 15 GPM. Inflows increase slightly during the spring snowmelt in conjunc- tion with increases in aquifer recharge. Any inflows from these sandstones will be pumped out of the tunnel, thus sustaining any base flow loses to the streams. As previously discussed these sandstones are too deep to be utilized as a water supply, and therefore no material damage will occur as the result of dewatering these sandstones. During low flows, fall and winter, water quality samples indicate some elevation of TDS, sulfates and SAR. It is believed this is attibutable to the Nos. 1 and 2 mine discharges and the old coal refuse pile. All stream flows are low thus dilution is not as high as in the spring/summer. None of the numbers 56 I�