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facilitate a mass balance analysis of substances added to the streams, the <br /> applicant will monitor the flow of Bear Creek and Dutch Creek. <br /> There are several areas at the Coal Basin mines where disturbance is less <br /> than 100 feet from a perennial stream. The disturbance at the <br /> preparations plant is less than 100 feet from both Dutch Creek and Coal <br /> Creek. In addition, the existing rock tunnel disturbance and portions of <br /> haul roads are less than 100 feet from Dutch Creek. The original stream <br /> channel will be restored. The original stream channel will not be <br /> affected, with the exception of the Dutch Creek channel reconstruction <br /> near the preparations plant which is a permanent feature. During and <br /> after mining, the water quantity and quality from the stream section <br /> within 100 feet of the surface coal mining operations will not be <br /> adversely affected. The runoff from the disturbed area at the <br /> preparations plant and rock tunnel is treated, then released. The haul <br /> roads will not adversely affect quantity and quality of water in the <br /> streams, as discussed in Section VII of this document. <br /> Ground water Hydrology <br /> Ground water occurs in both bedrock and alluvial aquifers in the vicinity <br /> of the Mid-Continent mining operations. Bedrock strata which have the <br /> potential to be labeled aquifers are the Upper sandstone, the Middle <br /> sandstone, the Rollins sandstone and all of the Mesa Verde Group. The <br /> alluvial deposits of Coal Creek also can be labeled an aquifer. The only <br /> known users of ground water in Coal Basin have all completed wells in the <br /> alluvial aquifer of Coal Creek. There are no known users of bedrock <br /> ground water from the Mesa Verde Group in the vicinity of the mine. Many <br /> of the other strata are water-bearing, but yield insufficient quantities <br /> of water to be considered aquifers. <br /> There are no alluvial aquifers which could be affected by subsidence. All <br /> the streams overlying the workings are bedrock controlled due to their <br /> steep gradients. Any effects to the alluvial aquifers in Coal Basin would <br /> be from mine discharge or sediment pond discharge. <br /> Three sandstone units in the Mesa Verde Group have the potential to be <br /> considered aquifers. In the Coal Basin affected area, the Upper sandstone <br /> is approximately 50 feet thick, the Middle sandstone is about 120 feet <br /> thick, and the Rollins sandstone is about 140 feet thick. Generally, the <br /> Rollins sandstone immediately underlies the "B" seam and the Middle <br /> sandstone immediately underlies the "V" seam. All of these sandstone <br /> units outcrop on the eastern wall of Coal Basin. This is where recharge <br /> to the aquifers probably occurs. From the outcrop, the sandstones dip to <br /> the west under Huntsman Ridge, and eventually, extend deep under the <br /> Piceance Basin. On the western side of Huntsman Ridge, the sandstones are <br /> located about 2,000-3,000 feet beneath the surface. There are no known <br /> users of this ground water primarily because of this great depth. The <br /> water yields that could be expected from these sandstones are too small to <br /> justify the great cost of drilling to this depth. Also, because of this <br /> great depth, no site-specific data has been collected regarding the <br /> hydraulic characteristics or water quality of these potential aquifers. <br /> However, the applicant estimates that permeabilities in the sandstone <br /> aquifers <br /> -18 <br />