2007-03-30_GENERAL DOCUMENTS - C1981018

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the permit area was completed in 1999, with operations shifting to the underlying "B" Seam, beginning with development mining in 1998/1999, and initiation of longwall extraction in early 2000. Mining operations and schedules were substantially altered by amine fire in Longwall Panel 9, in the northeast portion of the permit area, in January 1996. The entire "D" seam longwall mining district in the northern portion of the permit area was eventually sealed off, and the longwall equipment was not recovered. The Deserado Permit was previously renewed in July 2004 (effective October 2004). Operational status was most recently reviewed and summarized by the Division in Permit Revision 05, Dated 13 October 2004. Status of revisions approved and stipulations issued subsequent to Permit Renewal 04 approval is summarized in that document. Status of revisions approved and all stipulations is summarized below. Elevations at the mine site range between 5,300 and 5,900 feet above sea level. The permit area and adjacent areas are characterized by gently rolling to moderately steep landforms. Slopes range from 0 to 6 percent in the valleys and level uplands and up to 50 percent on drainage sideslopes. The area is semi-arid and characterized by light rainfall, low relative humidity, and moderate winds. Mean annual precipitation is 9 to 10 inches, with peaks in spring and late summer/early fall. The mine is located in the White River Basin, which is the eastern portion of the larger Uinta Basin. The mine lies within the interbedded sandstone and siltstone strata of the Mesaverde Group in the Williams Fork Formation. The Mesaverde Group consists of the Lower Iles Formation and the Upper Williams Fork Formation, which are separated by the Trout Creek Sandstone. The Williams Fork Formation is further divided into upper and lower members. The Lower Williams Fork Member contains coal bearing seams "A" through "H." The "B" and "D" seams will be recovered at the Deserado Mine. The dip of the Mesaverde Group within the permit area is controlled by the asymmetric Red Wash Syncline, which strikes northwest southeast. Dips vary from 7 degrees in the southern part of the permit area, horizontal at the synclinal axis, to as much as 70 degrees on the north flank of the syncline. The coal and sandstone beds outcrop along this steep northern flank. Structure and local topography are the main factors that control ground water movement in the area. The Williams Fork Formation is divided into three hydrologic units: The Sandstone Facies, which underlies the "A" coal seam and is generally equivalent to the Trout Creek Sandstone and the upper portion of the Iles Formation; the siltstone and Coal Facies, which consists of the interbedded coal, siltstone, and shale strata of the Lower Williams Fork Formation; and the upper Sandstone Facies of the Upper Williams Fork Formation. A fourth hydrologic unit is the alluvium of the White River and its tributaries. The maximum thickness of the White River Alluvium near the permit area was found to be 3