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North. In the southeastern corner of the permit area, near Streeter Fill, the Collom Syncline is <br />influenced by the Elkhorn Syncline which results in strata having an eastward dip and <br />north -south strike (see Map 7 and Figure 1 in the PAP). <br />There appears to be no evidence of faulting in the permit area; however, linear features that may <br />be fault - related have been observed from aerial photographs. These lineations trend <br />approximately north 70 degrees west, north 45 degrees west and north 30 degrees east, with near <br />vertical inclinations. <br />The coal- bearing strata of interest to the Colowyo operation are stratigraphically located in the <br />Mesaverde Group within the Williams Fork Formation of upper Cretaceous age. The Williams <br />Fork consists of alternating beds of sandstone, sandy shale, carbonaceous shale and coal. The <br />coal to be mined lies within a 392 -foot interval in the Fairfield Member of the Williams Fork <br />Formation. The quality of the coal seams is midway between bituminous and sub - bituminous. <br />Underlying these coal beds are 9,000 feet of Mesozoic and 4,500 feet of Paleozoic sediments. <br />The Williams Fork Formation is estimated to be 1,600 feet thick in the permit area and is <br />underlain by the ridge- forming Trout Creek Sandstone member of the Iles Formation. <br />Overburden material consists of a sequence of sedimentary claystones, siltstones, shales and <br />carbonaceous silty shales. These sediments are typical of the cyclothems deposited along the <br />western interior of North America during Late Cretaceous time. The site - specific stratigraphy is <br />described in Exhibit 6 and on Map 8 of the PAP. There are four coal seams below the "F" seam <br />which cannot be economically mined by surface mining methods. <br />Results of test borings are included in Section 2.04.6 Geology Description, Volume 12, for the <br />South Taylor and Lower Wilson Area. Test borings resulted in information on the presence of <br />subsurface water, characterization of the physical properties of the overburden, and testing and <br />evaluation of the geochemical properties of the overburden. Additional discussion of the results <br />of this testing can be found in Section III E of the findings section of this document. <br />4.6 Climate <br />Climatic information is found in Section 2.04.8 of Volume 1 of the PAP. The region is <br />characterized by a semi -arid steppe climate regime. Precipitation averages 18 inches per year <br />with a significant portion of this yearly precipitation occurring as snowfall. Prevailing winds <br />over the permit area are from the southwest and average eight to nine miles per hour. High winds <br />are not common, due to the protection afforded by local terrain. <br />4.7 Soils <br />Soils information is found in Section B, Item IV of this document, as well as in Section 2.04.9 <br />and Exhibit 9 of the PAP original volumes. Additional soils information associated with the PR- <br />Proposed Decision and Findings of Compliance January 2012 <br />Permit Renewal 06 Page 114 <br />