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Surface Water The immediate mine area contains no flowing streams or springs. Surface runoff flows through normally dry gulches to Carbon Creek and then to Ohio Creek. There are no streams, springs, wells, or irrigation ditches within aone-mile radius of the permit area. There are two stock ponds within a mile of the permit area that catch water after major precipitation events. The water flowing from the Nu Msne adit is the only consistent surface flow in the area. All surface water from the O.C. Mine No. 2 disturbed area passes through a sediment control system. Water from undisturbed areas is routed around the disturbed area by two diversion ditches. Information on surface water hydrology can be found on pages 7, 8, 9 and Exhibit 7 of the permit. Geology The O.C. Mine No. 2 is at the extreme southeast margin of the Piceance Basin. The area is in the Crested Butte Coal Field and is near the West Elk Mountains. Stratigraphically there are only 500 feet of sedimentary rock overlying the igneous intrusive basement rock. The area is underlain by interbedded non-marine sandstones, siltstones, shales, carbonaceous shales and coal beds assigned to the Mesaverde Formation. The base of the Mesaverde Fot7ttation is formed by the massive Rollins Sandstone. The Mesaverde Formation is overlain by the Ohio Creek conglomerate and underlain by the Mancos Shale. Coal is mined from the B seam in the Paonia shale member of the Mesaverde Formation which dips 2 to 4 degrees northwest. The B seam is 4.5 to 8 feet thick and is approximately 200 feet above the Rollins Sandstone. There are two other coal seams near O.C. Mine No. 2: The A seam that lies directly above the Rollins Sandstone and ranges in thickness from 2 to 3 feet, and the C seam that lies approximately 45 feet above the B seam in the area to be mined and is approximately 1 to 2 feet thick. Many faults are located in the Ohio Creek drainage. The area of mining at O.C. Mine No. 2 is surrounded on three sides by three faults. The faults locally offset the B seam by a few feet or more. Two of the faults on the north and east side have been precisely located by the mining operations, but the third has yet to be precisely located. The analysis of the roof and floor material show that the rock is mildly alkaline (pH = 7.8); that the conductivity is low, indicating low levels of soluble salts; that the sodium absorption ratio (SAR) is low, indicating a ]ow sodium hazard potential; that the level of heavy metals is below potentially toxic levels; and that the combustible solids are below the level at which a hazard of spontaneous combustion would be present. Based on these analyses, none of O.C. Mine No.2 Findings g May 15, 1992