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BY AUGUST 27, 1993, OAKRIDGE ENERGY WILL SUBMIT COPIES OF ITS MSHA ~ PERMIT AND COUNTY SEWAGE DISPOSAL PERMIT. Description of the Environment The Carbon Junction Mine is located in southwestern Colorado, approximately 2 1/2 miles southeast of Durango (Figure 1). Elevation of the area ranges from approximately 6800 feet to 7400 feet. The mine is located in the upper drainage basin of Carbon Junction Canyon. This is an intermittent tributary to the Animas River. The total drainage basin of Carbon Junction Canyon is 0.8 squaze miles. This drainage has a steep gradient and, through much of its reach, is contained within steep valley walls. The rock units exposed in the permit and adjacent areas are all Cretaceous in age. These units include the Lewis Shale, the Pictured Cliffs Sandstone, the Fruitland Formation and the Kirtland Shale. The Carbon Junction Mine will extract coal from the Lewis coal seam ("C" seam), Carbonero seam ("B" seam) and the Shamrock seam ("A" seam) within [he Fmitland Formation. Geology The applicant has supplied sufficient geologic information for the permit and adjacent areas within the permit application. Geologic information contained within the permit application can be found in Sections 2.04.5, 2.04.6; Table 4-l; Map 4-2; and Appendix 4-2 of the permit application. The proposed Carbon Junction Mine permit area is located on the northern rim of the San Juan structural basin in Southwest Colorado. The sedimentary strata in the permit area dip 26 [0 30 degrees to the southeast and strike North 45° West. There are no mapped faults within the permit and adjacent areas. Folding within the general area, however, has produced fracturing within the more brittle sandstone and coal strata. The sandstones are resistant to erosion and form prominent ridges and cliffs at outcrops. Stream valleys within [he area of the proposed mine are controlled by the geology. The Animas River has cut a steep sided valley perpendiculaz to bedding of the strata, and may be related to a fracture or fault trend. Carbon Junction Canyon, which is tributary to the Anitnas River, has cut a channel which parallels the bedding of the strata in the less resistant shales, coals and siltstones of the lower Fruitland Formation. The sedimentary rock formations within the permit and adjacent areas are of Cretaceous Age. These aze the Lewis Shale, the Pictured Cliffs Sandstone, the Fruitland Formation and Kirtland Shale. The Lewis Shale is the lowermost formation in the general area. This formation consists of between 1600 and 1800 feet of light to dark gray and black shales that contain interbeds of light brown sandstone, sandy to silty limestones, calcareous concretions, and bentonite. This formation is erosive and wide valleys have formed within this unit to the north.