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The only other MSHA regulation that could apply would be 30 CFR 75.1716. This concern has been previously addressed in a letter to your office dated January 10, 2003. To recap, the Elk Creek Mine is currently developing in the D-Seam. The abandoned Somerset Mine has workings in the C-Seam and B- Seam. The C-Seam workings are approximately 175 feet below the D-Seam, and the B-Seam workings are approximately 250 feet below the D-Seam. The Somerset Mine C-Seam Portal elevation in the Elk Creek drainage is at approximately 6150 feet. If the Somerset C-Seam workings were completely flooded to the outcrop, seepage would begin to appear at these portal locations. Because this outlet exists, it is unlikely that the water level could ever back up higher than the 6150' elevation. Currently, [here are workings in the Elk Creek Mine that are below the 6000' elevation. As stated, the worst possible case is that water would back up in the Somerset Mine to an elevation of 6150'. But this does not mean that all workings in the Elk Creek Mine that are below the 6150' elevation would be in danger. Both the C-Seam and the D-Seam are dipping to [he northeast at approximately 5%. This means water would have to migrate laterally for over 3500 feet to enter the Elk Creek Mine (See Drawing 2). Although it is possible for water to accomplish this feat given enough head and migrating in the same strata, i[ is highly unlikely to occur where the water must pass through many different layers of strata, including the finely grained Bowie Sandstone member directly below the D-Seam, and the finely grained shales found in the interburden. These shales are chazacterized by a very low permeability. There would also be a certain amount of head necessary to force the water through the strata. At the proposed water injection location, for example, the maximum pressure that could be maintained would be approximately I50 feet of head, or 65 PSI. It is unlikely that this amount of pressure could force water through many ]ow permeability seams for a distance of 3500 feet. Supposing that the water does not travel laterally, but takes the shortest path from the C-Seam to the D- Seam, and could pass through all of the interbedded shales and sandstones, this still would not pose any danger because [he interburden distance is greater than the maximum head of the water. It is physically impossible for water to reach the D-Seam workings. Oxbow Mining has not identified any major faults, joint structures, or other channels near the proposed water injection location. Under the worst case scenario with the Somerset Mine flooded to its maximum level, and supposing that a path along a geologic structure were present, the amount of interburden is still so great that migration of water from the Somerset Mine to the Elk Creek Mine is unlikely. Any water seen in the Elk Creek Mine would show up as a seepage at best, and not a massive, uncontrollable inundation. Oxbow Mining does not anticipate any problems associated with pumping water into the abandoned Somerset Mine. We request approval of this waste water disposal plan. If you have any questions, please contact this office a[ 970/929-5122. Yours truly, y~ ~,~ Randy Litwiiler Mine Manager