2009-06-15_GENERAL DOCUMENTS - C1982056 (2)

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• is composed of interbedded sandstone. siltstone. shale. and coal approximately 1.500 feet thick. The fine-grained, massive Trout Creek Sandstone member marks the top of the Iles Formation. This sandstone averages about 100 feet in thickness (Bass, et. al. 1955) and has been known to vary from 50 to 400 feet thick in the area, according to Cyprus Western. The coals in the Iles Formation are known as the Lower Coal Group of the Mesaverde Group. They have been mined a few miles south of the Foidel Creek Mine. The Iles Formation is not involved in the Cyprus Western mining operations. The Williams Fork Formation is composed of interbedded shale. siltstone. sandstone. and coal approximately 1,100 to 2.000 feet thick. The lower unit contains several minable coal beds and is known as the Middle Coal Group. These are the coals of interest to Cyprus Western and will be discussed in detail in subsequent sections of this report. Above the Middle Coal Group lies about 500 feet of marine shale that coarsens upward into the Twentymile Sandstone member of the Williams Fork Formation. The Twentymile Sandstone is a massive. fine-grained sandstone, ranging from 100 to 200 feet thick in this area. It outcrops near the Cyprus Western mine offices on Routt County Road 27. Above the Twentymile Sandstone lies more interbedded shale. sandstone. siltstone. and coal. This is known as the Upper Coal Group of the Mesaverde Group. The number of coal beds in this upper unit varies across the region, as does the thickness. In the Foidel Creek mine area, the only coal seam present is the Fish Creek seam that was mined out under federal coal lease C-20900. • Late Cretaceous Lewis Shale conformably overlies the Williams Fork Formation and is exposed to the north of the subject tracts. It is composed of predominantly marine shale with a few sandstone beds at the top. The thickness of the Lewis Shale varies considerably across the area. Quaternary stream sediment is located along Fish Creek north of Tracts A and B and is composed of primarily silt. sand, and shale. Minerals Coal: Tracts A and B lie within lands that were patented. reserving ditches, canals. and coal only to the United States. Federal coal lease C-081330 was originally issued on November 1, 1963. and has become part of a logical mining plan composed of federal. state. and private coal leases. South of the subject lands, coal has historically been mined by surface methods in the Eckman Park Mine (formerly known as the Energy Nos. 1. 2. and 3 strip mines). These pits are in the process of being reclaimed. Federal coal lease C-20900 overlies lands included in Tract B (Figure 3). It was issued in 1978 for the strippable coal reserves in the Fish Creek seam south of Fish Creek. These reserves have been mined out and the area reclaimed. • This area of the Williams Fork Mountains generally contains three consistent coal seams in the Middle Coal Group. In ascending order, these are the Wolf Creek. the Wadge, and the Lennox seams. The Wadge