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CRAPTERFOUR Enuironmenta~ conseuuences <br />Impacts associated with each of the alternatives aze discussed below, including effects on fragile <br />soils and reclamation potential. Other potential indirect impacts, such as accidental spills of <br />fuels, lubricants, or other materials, would likely have only minor and localized effects on soils. <br />Direct and Indirect Impacts <br />Soil disturbance would occur due to mine field development and due to construction of ancillary <br />facilities and roads. Clearing, grading, excavation, stockpiling, and replacement activities would <br />result in soil loss through erosion. Exposed soils would be susceptible to accelerated wind and <br />water erosion that could result in permanent soil loss and sedimentation of down>tream <br />drainages. The volume of soil lost due to disturbance would be site-specific and would depend <br />on factors including soil type, slope gradient and length, timing and intensity of precipitation, <br />and other factors. <br />Indirect impacts would include the loss of soil productivity during soil salvage attd stockpiling <br />and the mixing of topsoil and subsoil horizons during grading, construction of foundations, and <br />trenching. Mixing of soil horizons would lower productivity by diluting the supt:rior physical <br />and chemical properties of the topsoil with less productive subsoil. Construction activities also <br />lower soil productivity as a result of decreased biological activity, reduced organic matter content <br />of surface soils, and the breakdown of soil aggregates into loose particles. Soil compaction along <br />roads and in the facilities area would be caused by heavy equipment traffic. Compaction <br />damages soil structure and reduces pore space, which impedes the movement of <ur and water to <br />plant roots, resulting in lower growth rates. <br />Proposed Action <br />Direct impacts under the Proposed Action would include the incremental disturbance and <br />alteration of 1,097.5 acres of in-place, natural soils over the 30-yeaz life of the project. (Tlils <br />does not include 449 acres of temporary disturbance along the product pipeline construction <br />right-of--way (ROVE where herbaceous ground cover would be left in place and soils would not <br />be directly disturbed.) Acres of soil disturbance aze presented in Table 4.2-1; Tat~les B-4 and <br />B-5 in Appendix B show acres of disturbance by soil type. Long-term impacts would include the <br />disturbance of soils for process facilities, the existing test mine facility, access rofids, ponds and <br />rail facilities and would affect 128.5 acres for the life of the project. For the shore term, 486 <br />acres would be affected for construction activities including temporary disturbance of soils for <br />installation of the piping system, an electrical transmission line, a natural gas line and the product <br />pipeline. Mine panel disturbance, occurring in approximately five-yeaz increments, would affect <br />483 acres for the long-term. <br />Piceance Site <br />Only four of the seven soil types occurring on the Piceance Site would be impacted by project <br />development, but the majority of the disturbance would affect the Rentsac or Torriorthents soils, <br />both of which aze considered fragile soils due to shallow depths, moderate to very high <br />susceptibility to water erosion, and slopes that can exceed 35 percent. Acres of di~;turbance of <br />fragile soils aze presented in Table 4.2-1. Temporary construction disturbance would affect 2l3 <br />4-6 Soifs <br />