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2000 S-7 area. The coal bearing sedimentary strata of the Mesa Verde Formation are relatively Flat lying with a regional dip of approximately 5 degrees to the north/northeast. The principal mineable coal seams on the Iron Point Coal Lease Tract are the "D" seam and the "B" seam. The primary mineable coal seam on the Elk Creek Coal Lease Tract is the "D" seam. The overburden ovedying the D coal seam in both lease tracts is generally greater than 500 feet and reaches over 2,000 feet in parts of both lease tracts. ~. m Environmental Consequences -There would be negligible effect to the geological resources as a result of drilling activities in the Iron Point Exploration License Area. If leasing and mining proceeds on the Iron Point and Elk Creek Coal Lease tracts, coal would be removed by longwall mining techniques, and the overlying overburden material would be altered through subsidence. Subsidence would cause a gradual lowering of the surface after the longwall shearer removes the coal. Some cracking would be evident as the shearer passes, and cracking would be also evident along the fringes of the extracted longwall panels. Due to the thickness of the overburden in the two lease tracts, subsidence would not be easily seen by casual observers. The historic (pre-mining) burning of the coal along the outcrop (causing the reddish coloration in the strata in the valley) would preclude a significant amount of mining close to the outcrop; therefore, rock falls induced by subsidence would be unlikely. There is a potential that mining subsidence could aggravate existing landslides in the Hubbard Creek drainage. Areas with less than 500 feet of overburden cover to the coal seam would show "high to very high" subsidence potential. The potential for subsidence to impact surface resources are lessened with the depth of overburden. Potential subsidence impacts of "low to very low" are typiglly those areas greater than 1,500 feet of overburden depth to the coal seam. S-3.4 Soils Existing Conditions - A total of 32 soil map units, characterized by 38 soil series, families, or miscellaneous groupings, were delineated within and surrounding the lease tracts and exploration license area. These soils are forming in response to a wide variety of parent materials, elevations, slopes, aspects, and rates of material weathering common to the region as a whole. Environmental Consequences - If exploration and leasing with subsequent mining activities occur, approximately 33.5 acres of surface could be disturbed by the construction of various boreholes, shafts, light-use access roads, and drill pads. Impacts to soils include the salvage and stoGcpiling of selected soils for later re-application, along with potential compaction and erosion. Given the size and form of the individual facilities comprising the proposed disturbed acreage, as well as regulatory requirements for revegetation, any impacts to soils would be limited and considered to be short-term and mitigable. The disturbance of 33.5 acres amounts to less than 1 percent of the acreages inGuded in the lease tracts and exploration area as a whole. S-3.5 Surface Water Existing Conditions -The North Fork of the Gunnison River is located south of the coal lease tracts and exploration license area. Hubbard Creek and Terror Creek drain the Iron Point Exploration License Area and the Iron Point Coal Lease Tract. Hubbard Creek, Bear Creek, and a small portion of Elk Creek drain the Elk Creek Coal Lease Tract. Hubbard, Terror, Bear and Elk creeks are tributaries to the North Fork of the Gunnison River. Hubbard and Terror creeks are perennial drainages in the area. Bear and Elk creeks are ephemeral drainages, flowing only in response to snow melt or severe thunder storms. The surface water quality of Hubbard and Terror creeks and the North Fork of the Gunnison River is calcium bicarbonate type water. Final Environmental Impact Statement