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during low flow periods through springs and seeps. If the mine were to experience mine <br />inflows, the ground water depleted from the hydrologic system would not be significant. <br />Therefore, the depletion of ground water will not impact the quantity of water tributary to the <br />alluvial valley floor. <br />The Division has sufficient information to determine the absence of alluvial valley floors in <br />Stove and Buniger Canyons. Sideslopes in the canyons are excessively steep (16 to 50 %) <br />and are deeply incised. The potential for extensive deposits of unconsolidated alluvium is <br />minimal Further, because these drainages encompass less drainage area than that of Munger <br />Canyon, it is likely that there is insufficient surface water runoff to sustain agricultural <br />activities. The fact that both streams are ephemeral indicates a low potential for subirrigation <br />by springs or seeps. Inspection of 7.5 minute topographic maps also indicates that there is no <br />irrigation along any stream courses in these drainages. <br />The water quality in Stove Canyon and Buniger Canyon will not be effected by mining since <br />there are no surface disturbances planned in these drainages. The quantity of water in these <br />drainages may be affected to a limited extent if surface waters are diverted into the mine <br />workings through natural or mining- induced fractures. Slopes of the natural surface in the <br />affected drainages range from 2v:1 h to 6v:1 h. On such high angle slopes, rainfall incidental <br />to the surface would have a greater tendency to flow over the surface than to infiltrate into <br />any mine workings. <br />The area of Stove and Buniger Canyons which would potentially be affected by subsidence <br />over mine workings for this permit term is approximately 185 acres. The Big Salt Wash <br />drainage basin encompasses 31,448 acres above the confluence with Stove Canyon. <br />Approximately 0.6% of the drainage area of Big Salt Wash could be effected by the operation <br />in this worst -case scenario. This fact indicates that there is very little potential for any effect <br />on the quality of water in Big Salt Wash as a result of this operation. <br />It is apparent from this discussion that the potential for diminution of quantity and quality of <br />water supplied to the Big Salt Wash potential alluvial valley floor would be minimal. The <br />Division finds that there will be essentially no effect of the operation on the hydrologic <br />character of the Big Salt Wash drainage system. <br />Grand Valley Coal Company has established surface water monitoring stations upstream and <br />downstream of the confluence of Munger and East Salt Creeks. Additionally, Grand Valley <br />Coal Company will monitor mine inflows, mine discharges, ground water downgradient of <br />the waste rock pile, coal processing waste pile and central facilities area, and ground water in <br />the alluvium of East Salt Creek. The monitoring system established by Grand Valley Coal <br />Company will be sufficient to verify conclusions of the Division with respect to the effect of <br />the operation on water quality and quantity and will indicate if any problems arise which may <br />require mitigation. <br />Therefore, pursuant to 2.06.8(5)(iii), the Division finds the proposed operation will not <br />materially damage the quantity and quality of water in surface and ground water systems that <br />38 <br />