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Mountain Coal Company Wesl Elk Mine Post Office Box 591 Somerset, Colorado 81434 Telephone 970 929-5015 Fax 970 929-5595 March 31, 1997 Mr. David Berry Mr. Mike Boulay DIVISION OF MINERALS AND GEOLOGY Office of Mined Land Reclamation 1313 Sherman Street, Room 215 Denver, CO 80203 RECEIVED APR 0 71997 Division of Minerals 8 Geology Re: West Elk Mine, Permit No- C-80-007, 1st Southeast Headgate.lntlow Update Dear have & Mike: III IIIIIIIIIIIIIIII /\ As you know, Mountain Coal Company ("MCC") experienced a lazge and unexpected inflow of water in Entry No. 2 near Cross-cut No. 11 of the 1st Southeast Headgate on January 20, 1997. In the days that followed, while we were establishing systems to manage the water, we had frequent conversations with you and with representatives of the Colorado Water Quality Control Division (" WQCD"j to seek advice and consensus regarding the best way to manage the mine inflow water, as well as to provide information and updates regarding our progress to safely manage the water. I apologize that 1 have not, until now, had a chance to provide you with a written report of the situation, but want to take this opportunity to summarize how we responded to the inflow event itself and to describe the measures we have taken or intend to undertake to more efficiently manage future inflows. The inflow began at approximately 10:30 p.m. on January 20 when a development mining crew cut through a faulUfracture in Entry No. 2 between Cross-cuts Nos. 10 and 11. We estimate that the inflow initially was approximately 8,000 gallons of water per minute. This flow literally chased the mining crew out of the section and submerged several pieces of mining equipment. The fault is oriented in a N70°E direction similar to the B East Mains fault . Because MCC (and its consultants) had not observed the fault from lineament or other geotechnical evaluations of the surface lands, nor had drilling in the area detected a fault of this nature, we did not expect to encounter this fault nor the associated body of water. As you know, we were prepared to manage inflows of the size we had previously encountered in the B East Mains (i.e., up to about 3,000 gpm), but we weren't prepared for an inflow event as large as the one we encountered on January 20. Nonetheless, the West Elk Mine crews worked very diligently and succeeded in containing and controlling [he inflow to minimize the impact on our future mining operations and [he impact on the North Fork of the Gunnison River. Initially, the water spilled over the 1st Southeast Headgate section and flowed down-dip to the Box Canyon Mains section. Fortunately we were able to remove all of our mining equipment from those Mains before the area was overtaken by water (please see the attached Shoreline Diagram). The "shoreline" of the water advanced to Cross-cut No. 4 of the Box Canyon Mains on January 23. The decision was then made [o retreat men and equipment out of the I st Northeast Tailgate Section as the shoreline was still advancing toward the (nearly full) Nonheast Tailgate sump. Finally, after four days ofround-the-clock pumping and pipe installation, anon- advancing shoreline was established on January 24. The shoreline of the water began to recede late in the afternoon of January 24. After it was confirmed that the water inflow and shoreline were receding, steps were taken to re- install equipment in the 1st Northeast Tailgate section, so that development mining could be resumed- At the same time we were working to control the inflow, we contacted several consultants to assist us in investigating the cause of the event and, more importantly, to determine the source of the water and any potential impacts to the North Fork of the Gunnison River. In particular, we engaged Wright Water Engineers, Inc. and Mayo and Associates to assist in evaluating the probable hydrologic consequences of the inflow and to analyze the