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There appeazs to be no evidence of faulting in the permit azea; however, lineaz features that maybe fault-related have been observed from aerial photographs. These lineations trend approximately north 70 degrees west, north 45 degrees west and north 30 degrees east, with neaz vertical inclinations. The coal-beazing strata of interest to the Colowyo operation are stratigraphically located in the Mesaverde Group within the Williams Fork Formation ofupper Cretaceous age. The Williams Fork consists of alternating beds of sandstone, sandy shale, carbonaceous shale and coal. The coal to be mined lies within a 392-foot interval in the Fairfield Member of the Williams Fork Formation. The quality of the coal seams is midway between bituminous and sub-bituminous. 9,000 feet of Mesozoic and 4,500 feet of Paleozoic sediments underlie these coal beds. The Williams Fork Formation is estimated to be 1,600 feet thick in the permit area and is underlain by the ridge-forming Trout Creek Sandstone member of the Iles Formation. Overburden material consists of a sequence of sedimentary claystones, siltstones, shales and cazbonaceous-silty shales. These sediments aze typical of the cyclothems deposited along the western interior ofNorth America during Late Cretaceous time. The site-specific stratigraphy is described in Exhibit 6 and on Map 8 of the PAP. There are four coal seams below the "F" seam which cannot be economically mined by surface mining methods. These seams are described in the Northwest Colorado Environmental Imnact Statement, Site-Specific Anal. Results of test borings are included in Section 2.04.6 Geology Description, Volume 12, for the South Taylor and Lower Wilson Area. Test borings resulted in information on the presence of subsurface water, characterization ofthe physical properties of the overburden, and testing and evaluation of the geochemical properties of the overburden. Additional discussion of the results of this testing can be found in Section III E of this document. 3.2.6 Climate Climatic information is found in Section 2.04.8 of Volume 1 of the PAP. The region is chazacterized by a semi-azid steppe climate regime. Precipitation averages 18 inches per year with a significant portion of this yeazly precipitation occurring as snowfall. Prevailing winds over the permit azea aze from the southwest and average eight to nine miles per hour. High winds aze not common, due to the protection afforded by local terrain. 3.2.7 Soils Soils information is found in Section B, Item IV of this document, as well as in Section 2.04.9 and Exhibit 9 of the PAP original volumes. Additional soils information associated with the PR-2 South Taylor and Lower Wilson expansion areas is included in Section 2.04.9 of Volume 12, Exhibit 9 of Volume 13, and Maps SA, SB, and SC of Volume 14. The most prevalent soils, including Bumette, Work, Lamphier, Rhone, and Northwater Loams, are mollisols of the suborder boroll, which developed from residuum or colluvium on gently sloping to rolling ridgetops, moderately steep sideslopes, and in gently sloping, concave narrow stream valleys. Shallow, rocky soils of the order Proposed Decision and Findings of Compliance 4 May 2007 Permit Revision 02 Page 1 S