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approximately 2 miles southeast of the town of Naturita in Montrose County. The <br />permit area overlies part of the Nucla-Naturita Coal Field. The area is characterized <br />topographically by dissected mesas sloping to the north toward the San Miguel <br />River. The region is underlain by sedimentary rocks of Jurassic and Cretaceous age <br />which dip gently to the north. The entire permit area is underlain by the Lower <br />Cretaceous Dakota Sandstone, which consists of interbedded conglomeratic <br />sandstones, dark-gray carbonaceous shale, and numerous coal seams. Five coal <br />seams are present in the Dakota Sandstone in the permit area, three of which are of <br />minable thickness. <br />Underlying the Dakota Sandstone is the Lower Cretaceous Burro Canyon <br />Formation, which is approximately 150 feet thick. It consists generally of two beds <br />of conglomeratic sandstone, each 10 to 40 feet thick, separated by a shale sequence. <br />The lower sandstone of the Burro Canyon Formation contains the only significant <br />ground water accumulations in the permit area. This aquifer lies 90 to 100 feet <br />stratigraphically below the lowest coal seam to be mined. The applicant has <br />monitored wells BW-1, BW-2, and BW-3 to establish pre-mining water levels and <br />quality. Yield from these wells vary from zero to three gpm. No other ground water <br />development has taken place in the vicinity of the permit area. <br />Five springs or seeps have also been located in and around the permit area at the <br />contact of the Burro Canyon and the underlying Morrison Formation. The discharge <br />of these springs is generally so slight as to be unmeasurable, and most have been dry <br />since the second quarter of 1989. Specific conductivity of the water varies from <br />approximately 1100 to 1700 umhos/sec. <br />Potential impacts to ground water from the operation include: <br />- Lowering of water levels in the Burro Canyon aquifer; <br />- Contamination of the Burro Canyon aquifer; <br />Lowering of water levels in alluvial aquifers of Bramiers Draw and <br />Section 33 Creek; <br />- Contamination of the same alluvial aquifers. <br />As described above, relatively continuous sandstones in the lower Burro Canyon <br />Formation yield small amounts of water to wells and are the source of several small <br />springs and seeps in and around the permit area. Along with the rest of the <br />stratigraphic section, this formation dips to the north at 2 to 3 degrees in the area. <br />Discharge to the surface occurs at the seeps mentioned above. The formation does <br />not outcrop within the permit area. Recharge to the Burro Canyon likely occurs well <br />south of the permit area, and perhaps across bedding planes from adjacent <br />finer-grained shales of the Burro Canyon and Morrison Formations. Approximately <br />90 to 100 feet of interbedded shale, coal, and sandstone lenses separate the aquifer <br />from the floor of the proposed mining pit, and there is no evidence that the aquifer is <br />under sufficient head to cause leakage from the aquifer into the pit. <br />13