Laserfiche WebLink
• <br />REGISTER ELIGIBILITY CRITERIA (36 CFR 60.6). SHOULD A RESOURCE BE FOUND <br />ELIGIBLE FOR LISTING IN CONSULTATION WITH THE REGULATORY AUTHORITY, THE LAND <br />MANAGING AGENCY (IF THE SITE IS LOCATED ON FEDERAL LANDS) AND THE STATE <br />HISTORIC PRESERVATION OFFICE, THE OPERATOR SHALL CONFER WITH AND OBTAIN THE <br />APPROVAL OF THESE AGENCIES CONCERNING THE DEVELOPMENT AND IMPLEMENTATION OF <br />MITIGATION MEASURES. <br />At the time of approval of the original permit application the Office of <br />Surface Mining received concurrence on a "No Effect", "No Adverse Effect" <br />recommendation from the Colorado State Historic Preservation Office. <br />With the acceptance of the above stipulation, the operation is in compliance <br />with the requirements of this section. <br />IV. Geology - Rules 2.04,5 and 2.04,6 <br />Information on the geology of the area to be mined can be found in Exhibits 7 <br />and 14 of the permit renewal application. <br />The O.C. Mine No. 2 is located at the extreme southeast margin of the Piceance <br />Basin. The area is situated within the Crested Butte Coa) Field and is near <br />the West Elk Mountains. Stratigraphically there are only 500 feet of <br />sedimentary rock overlying the igneous intrusive basement rock. The area is <br />underlain by interbedded non-marine Sandstones, siltstones, shales, <br />carbonaceous shales and coal beds assigned to the Mesaverde Formation. The <br />base of the Mesaverde Formation is formed by the massive Rollins Sandstone. <br />The Mesaverde Formation is overlain by the Ohio Creek conglomerate and <br />underlain by the Mancos Shale. <br />Coal is mined from the B seam in the Paonia shale member of the Mesaverde <br />Formation which dips 2 to 4 degrees northwest. The 6 seam is 4.5 to 8 feet <br />thick and is located approximately 200 feet above the Rollins Sandstone. <br />There are two other coal seams in the vicinity of O.C. i4ine No. 2: The A seam <br />which lies directly above the Rollins Sandstone and ranges in thickness from 2 <br />to 3 feet, and the C seam which lies approximately 45 feet above the B seam in <br />the area to be mined and is approximately 1 to 2 feet thick. <br />Numerous faults are located in the Ohio Creek drainage. The area of mining at <br />O.C. Mine No. Z is surrounded on three sides by three faults. The faults <br />locally offset the B seam by a few feet or more. Two of the faults on the <br />north and east side have been precisely located by the mining operations, but <br />the third has yet to be precisely located. <br />The analysis of the roof and floor material indicates that the rock is mildly <br />` alkaline (pH = 7. B); that the conductivity is low, indicating low levels of <br />soluble salts; that the sodium absorption ratio (SAR) is low, indicating a low <br />sodium hazard potential; that the level of heavy metals is below potentially <br />toxic levels; and that the combustible solids are below the level at which a <br />hazard of spontaneous combustion would be present: Based on these analyses, <br />none of the material is found to contain any toxic or physically unstable <br />properties which might pose an environmental problem. The results of the <br />analyses are contained in Exhibit 14 of the permit. <br />The operation is in compliance with the requirements of this section. <br />-B- <br />