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Salvage operations will not be performed on slopes that are steeper than 21b:1v due to the poor quality of soil materials on such slopes, equipment limitations and personnel safety considerations. Topsoil on steep slopes generally lacks or has poorly developed O-horizons and A-horizons due to elevated erosion rates and poor soil-fomung conditions. As a result, only small amounts of low-value soil resources will be sacrificed by not salvaging soils from steep slopes. Thirteenmile Tongue soils will require special consideration and handling; during mining and reclamation activities. This outcrop supports two plant species that aze federally listed as threatened, the Dudley Bluffs bladderpod (I.esquerella congesra) and the Dudley Bluffs twinpod (Physaria obcordara). These plants are apparently endemic to the'I'hirteenmile Tongue soils. Additionally, small stands of ponderosa pine, which the BLM considers to be remnant vegetation in the Piceance Creek Basin, also appeaz to be strongly associated with the Thirteenmile Tongue. BLM's No Surface Occupancy stipulations establish "no disturbance buffer zones" azound known occupied sites of T&E species in an effort to prevent direct imparts to populations of these species. While occupied T&E plant species habitats receive protection, disturbance activities in unoccupied portions of the Thirteenmile Tongue might also result in adverse impacts to future potential T&E species habitats. This could occur because these two plant species are restricted in distribution and are apparently adapted to the bazren, shallow soils of the Thirteenmile Tongue. It is possible that removal of the shallow bedrock and replacement with a deeper, less compacted plant growth medium might encourage the l;rowth of other plant species that would preclude the colonization of this potential habitat by these two species after reclamation is completed. In an effort to avoid such potential future impact, salvage and reconstruction operations • involving these soils will exercise great caze. These soil materials generally consist of a thin layer of topsoil• with a max;mum profile thickness of 3 inches, undel-lain by subsoil that averages 13 inches in thickness. The subsoil is characteristically very rocky and has poor infiltration rates. Should potential T&E species habitat disturbance become necessary, the topsoil and subsoil will be salvaged, stockpiled and reconstructed through sepazate, distinct operations. The topsoil will be salvaged and replaced in a thin veneer to preserve to the extent possible its inherent fertility and physical chazacteristics. Particulaz care will be taken to avoid mixing or improving these soils during handling or reconstruction such That more competitive plant species could become established and be favored by a deeper prn£ile plant growth medium. Soils salvaged from this outcrop will be reconstructed to simulate their original characteristics as nearly as possible. Prior to or during soil salvage operations, the subsoil structure and other unique characteristics will be documented to later aid in their eventual reconstruction (see Section 5.1.2). American Soda, in consultation with the BLM, intends to develop a specialized protocol for dealing with the Thirteentnile Tongue soils as the Yrinkee Gulch. Project progresses. When salvaged soils require storage prior to respreading, they will be placed in designated stockpile locations as near as possible to excavation locations. Stockpile;s will be located on stable sites where wind and water erosion potentials are minimized. Stockpile aeeas will avoid or be adequately protected from concentrated surface flows. Stockpiles will be located in areas that are not planned to be disturbed by future operations. Soil will be selectively stockpiled according to material type (i.e., range site type and horizon). American Soda, L.L.P. 4-4 Soil Conservazion. Plosion and Sediment Coovol. Reclamation, and Rcvegeration Plan Ocro6er 28, 1998 Revised April 9. 1999