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The only ground water aquifers that have the potential to be impacted by <br /> mining (the aquifers discussed above) are those used by the applicant. <br /> Several mine production wells are completed into the alluvial aquifer of <br /> Coal Creek. See Table III-C-3 of the permit application for a <br /> description of all private water wells in the area. No wells are known <br /> to be completed in the coal -bearing strata of the IMesaverde Group in the <br /> vicinity of the mine. <br /> The applicant proposes to mine both the Coal Basin coal seam ("B" seam) <br /> and the Dutch Creek coal seam ("V" seam) by underground mining methods <br /> (see Figure III-0-1 of the permit application for stratigraphic <br /> relationships) . The mine entries will be located near the outcrop of the <br /> seams. No significant physical disturbance of adjacent strata will occur <br /> as a result of the mine entries. <br /> In addition, the applicant proposes to construct a tunnel which will <br /> connect the 2 seams currently being mined. This tunnel will be used to w. <br /> more efficiently transport coal out of the mines. The tunnel entry will <br /> be located in the underlying Mancos shale formation and will continue up <br /> the stratigraphic section until it intersects with the Dutch Creek coal <br /> seam. It will cut through 3 sandstone units that are considered <br /> potential aquifers. They are, in stratigraphically ascending order, the <br /> Cozzette, Rollins, -and Middle sandstones (see Figure III-D-1 of the <br /> permit application) . The waste rock generated during th construction <br /> of this tunnel will be disposed of near Dutch Creek. Q <br /> 4+� �he mines dewater the co s and adjacent strata as part of normal iS v <br /> ,operations. This dewat rocess will cause water levels in some <br /> pur aquifers to be lowered. The decline in water levels should not extendY/ <br /> f more than a mile from the edge of the mine workings. This effect should f, <br /> be temporary in nature. When mining is completed, the water levels in �. <br /> the aquifers should return to pre-mining elevations. <br /> Other effects on ground water will be a slight mixing of ground waters <br /> from previously unconnected aquifers as a result of the proposed rock <br /> tunnel and a slight degradation of alluvial water from the coal <br /> processing waste pile and the rock tunnel waste pile. None of these <br /> impacts are expected to cause material damage to ground waters in the <br /> Coal Basin area. For further discussion of impacts, see Section VII of <br /> this document; Probable Cumulative Hydrologic Impacts. <br /> Ground water quality and water levels are measured in the 12 alluvial <br /> wells shown on ,,lap IV-C-1 of the permit application. ',Dater levels in <br /> these wells are measured monthly and the water is sampled quarterly. <br /> Ground water quality data collected from four of these .veils are wI <br /> presented in Appendix III-E-2, Figure III-E-2, and Table III-E-1 of the <br /> permit application. An additional eight monitoring wells were completed <br /> and monitoriny commenced in Jctober, 1982. <br /> The Jivision has reviewed the ground water monitoring program proposed by r'WIR <br /> the aoplicant. The recuirements of the ;noniforir.g are oriented towards <br /> verifying the probable nyorologic consequences ciscussed in 5--ti^n YII Q <br /> N der N r� <br /> �w w� <br />