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Mountain Coal Company West Elk Mine Post Office Box 591 Somerset, Colo2do 81434 Telephone 970-929-5015 July 14, 1997 Mr. Michael Boulay III IIIIIIIIIIIIIIII 999 /\ ~FCEIVED Colorado Division of Minerals and Geology JUL ~ 5 1897 Office of Mined Land Reclamation 1313 Sherman Street, Room 215 Divielon or mllnerals & Geology Denver, CO 80203 RE: Minor Revision No. 219 (Revised Ventilation Shaft #3 Site); West Elk Mine; Permit No. C-80-007 Dear Mike: Mountain Coal Company (MCC) requests a minor revision to revise the pad design associated with Ventilation Shaft #3 per MR #216. During drilling of the pilot hole for Shaft #3, it was discovered that competent bedrock is at elevation 7,010 feet, which would require a shaft lining depth of 55 feet from the original pad elevation of 7,065 feet (per MR #216). The safe, practical maximum depth of shaft lining using conventional equipment for a small diameter shaft such as Shaft #3, is approximately 20 feet. if the lining were more than 20 vertical feet, larger equipment to complete the shaft would be required and a larger pad footprint would be needed. It was also discovered that the original pad layout would require a significant amount of rock blasting above the northeast corner of the pad. To maintain the smaller pad footprint, the elevation of the pad has been lowered to elevation 7,030 feet. To eliminate the need for rock blasting and the resulting rock highwalls above the pad and shaft, the pad location was shifted approximately 125 feet to the southeast. The shaft location remains the same, but is now located in the northwest portion of the pad. The road to the pad was also realigned and flattened beginning at station 14+57. Please note that there are no changes to the electric borehole road or pad, degasification borehole road, or the road to station 14+57. Construction of the pad will be from the top-down. Topsoil will be stripped and diversion ditches and temporary drainage will be established, prior to beginning the construction of the upper-most bench. MCC anticipates that removing the entire area of topsoil will allow more careful evaluation of the original ground surface. MCC will consult with one or more geotechnical engineering firms during the construction of the cut. MCC plans to utilize soil nailing techniques or other methods to stabilize the benches should they show signs of instability. MCC will also include construction information in the weekly reports currently being submitted to CDMG per PR #07.