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• ~ ALTEF.NATIVE ACTI015 Alternative I,io. 1: OSP: may concur with the State do • stipulations (see Attachment A to this environmental the operator's mining and reclamation plan (A1RP) and 1987. currents, conclusions, and a::sessment) and approve issue a permit through Alternative ;i~o. _°°: OSM map disapprove the NRP and no[ issue a permit through 1987. (This alternative is the equivalent of the customary "no-action" alternative.) Alternative No. 3: OS''! may approve the P*P.P and issue :i permit through 1987, subject to certain stipulations (Attachment B) over and above the State documents, conclusions, and s*_ipulations. This altern~stive is OSt!'s "preferred alternative" and is referred to elsewhere as such. AFFECTED ENVIROt~•fEP:T Land Features, Climate. and Vegetation The Trapper t3ine is located on the north-facing slope of the Williams Fork mountains at the 6500 to 7500 foot elevation. The k'il:Liams Fork mountains form a long ridge running east-west at elevations between 7400 and 7700 feet. The mine is located on a near dip-slope, with the strata dipping slightly more than the slope of the topography. Two recognizable bedrock formations outcrop in the immediate vicinity of the mine: the Williams Fork formation of the Mesa Verde Group, and the Lewis Shale formation. The coal seams being recovered at the Trapper Mine (H, I, L, Q, Q-rider, and R-rider) exist wholly within the [•;illiams Fork formation. No major faults have been identified in • the vicinity of the mine, which lies on the south limb of the Big Bottom Syncline. The average annual precipitation for the area is 13.5 inches, of this over one-third is snowfall (averaging 66.5 inches/year). The mean annual temperature is 43°F, with recorded extremes of -45oF and +100°F. Winds are predominantly from the west, but are locally modified by geomorphic features. The growing season for the area around Craig averages 77 days. The permit area is occupied by three soil orders: Aridisols, Entisols, and Mollisols. The presence of these three orders is characteristic of fairly steep, semi-arid regions of northwestern Colorado. These orders represent soils that grade from recently developed soil bodies with minimum horizon development to older soils with well-defined diagnostic horizons. Overall, the soils found in the proposed permit area are relatively deep and fairly well-drained. Effective rooting depth varies from 20-~60 inches within the area. The deepest soils yielding the greatest rooting depths occur within valleys and the leeward side of ridges. Soil reactions are slightly acid to moderately alkaline over the area with the exception cf some small scattered areas with saline substrata. These small areas have probably formed in place from weathered sodic shales. -~- C 1