2008-03-21_GENERAL DOCUMENTS - C1980007 (3)

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with proposed methane drainage wells in the South of Divide and Dry Fork lease areas were being reviewed by the Division in early 2008.) E Seam mining of longwall panels 10, 11, and 12 was approved in PR-6 and is planned to occur prior to the mining the underlying B Seam panels. Mountain Coal Company mined in the F Seam from 1982 to 1991 in leases D-004569 and C-0117192. This mining was only marginally successful. Poor mine roof conditions, sandstone channels, low coal areas, poor coal quality areas, and other unfavorable conditions have negatively affected mining and rendered the F Seam uneconomic under past and present market conditions. Mining in the F Seam has been discontinued, pending improved economics for this seam. In April 1989, an application for a technical revision for an incidental boundary change to add 35.5 acres to the permit area was submitted. The revision was for access and associated activities by way of slopes and a ventilation shaft from inside the existing F Seam workings to the B Seam. The revision also included mining in the B Seam by room and pillar, as well as longwall mining methods. The 35.5-acre incidental boundary change was necessary to accommodate the B Seam main access entries. The Division subsequently issued a proposed decision to approve the revision on July 12, 1989. In January 2000, elevated levels of indicator gases showed there was probable combustion in gob in a mined-out area of the B-West mains. Operations were curtailed and MCC immediately began an operation to access the B-seam by drilling into the mine from the Apache Rocks area above. Approval was obtained from both the Division and the U.S. Forest Service to initiate a drilling program in that area. Nineteen 4-inch boreholes were drilled for locating the combustion area and water was pumped into that part of the workings. In the spring of 2001, MSHA gave MCC permission to curtail the pumping of water, so the company completely sealed off the area underground and initiated the approved reclamation of the disturbed ground on the surface. A second episode of elevated levels of gas occurred in the mine in late 2005, necessitating the drilling of several boreholes from the surface to the B Seam workings in the Box Canyon area. Approval was obtained for the construction of roads and drilling the boreholes. Water and foam were pumped down into the workings and mining resumed within approximately three months. No major buildings, major structures, occupied dwellings, cemeteries, parks, railroads or highways overlie the coal to be mined. Two reservoirs lie close to the F Seam outcrop; however, neither is directly over the coal to be mined. Ventilation in the mine is provided by a fan in Sylvester Gulch. Power to the mine is supplied via existing lines of the Delta-Montrose Electric Association. Power is stepped down at a substation in the main mine facilities area for powering underground operations and the surface facilities. With Permit Revision No. 7, MCC constructed an air intake shaft and an exhaust shaft within Sylvester Gulch. Mountain Coal Company submitted Technical Revision 93 in 2001 to add to the permit application the sealing of bulkheads at the Lone Pine fan portal. Mining ceased in the Lone Pine portion of the mine in early 2001 and the workings served by the fan portal were sealed off 16