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F)~can~6er 9.2003 3.4.1 Existing Conditions Surface Water The LBA tract area encompasses portions of the Raven Creek watershed, which is tributary to the North Fork of the Gunnison River. The unnamed drainage in Section 13 (T13S, R90W) is the only drainage overlying potential coal extraction areas in the LBA tract, and is an ephemeral drainage, flowing only in response to snowmelt runoff or intense thunderstorm events. Dry Creek, which is a perennial stream in the southeast portion of the lease tract area, would be outside the proposed underground mining area. Raven Creek is a perennial drainage and flows through the northeast portion of the lease tract. The 8 seam mine plan, assumed as the RFDS, does not propose mining beneath this area. Ground Water Given the relatively steep gradients of the drainage channels in the LBA tract area, there are limited shallow alluvial or colluvial deposits that could provide far shallow ground water bearing deposits. The unnamed drainage in Section 13 does not receive enough water to maintain year-round flows or to saturate the minor alluvial/colluvial deposits in the drainage. No known springs occur in the LBA tract. r~ U Bedrock contains ground water to a limited degree, and it occurs in the LBA tract area in isolated perched zones and in fracture/fault areas. Ground water may also occur in the coal seams and associated strata. In the lease tract area, the coal seams and associated strata dip to the northeast. The upper units outcrop in the North Fork Valley and are drained over a large area such that ground water occurrences in these units are rare. The B seam and the overlying coal interburden and overburden units are generally well • drained on the.riorth side of the North Fork of the Gunnison River within and in the vicinity of the lease ~ - tract area. In general, the coal seams mined in the North Fork Valley are dry. The West Elk,mine has encountered ground water inflows associated with faults and fractures. The ground water encountered was determined to be part of a deeply circulating system, which has been out of contact with the atmosphere for several thousand years. The BLM reports that the anticipated moisture of the coal in the LBA tract is about five percent. Experience in the area shows that the Mesaverde strata are minimally saturated. This is due to the relative impermeable nature of the strata, and that recharge is minimal. The steep slopes in the area promote runoff rather than infiltration of precipitation. MCC has experienced water inflows when mining has intercepted faults. The amount of water has varied from a few gallons to thousands of gallons. This intercepted ground water has ceased flowing over the period of a few weeks. There has been no indication that the water encountered in the mine is in connection with water resources on the land surface. Chemical testing has shown that ground water encountered in the mine is part of a deep, inactive ground water system that is not in direct contact with near-surface water. Faults are anticipated in the lease tract, and although it is uncertain whether these faults would contain water, it was assumed for this analysis that faults encountered during underground mining activities may flow around 1,000 gpm for a few days when encountered, then cease flowing (Koontz, 2003). Any ground water encountered would be handled by the existing system in place in the MCC underground operation. Any water discharged would beat the National Pollutant Discharge Elimination System (NPDES) permit point and would meet discharge water quality standards. ..nvironmer,~ai II,esesei;7ent 4"lest t=fa:~;an I_~~`. -i ract L+uIlC IS:]il i~Ol: r;iti, ~;nir;{~3 ~i0 Pace 3-Ei •