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<br /> <br /> <br />permit area, range from approximately 40 inches at the higher elevations to about <br />60 inches at the lower elevations. The eastern portion is more variable because <br />of the numerous swales and ridges that dominate this area, and the more abundant <br />vegetative cover (see Section 2.3). On the be [ter developed soils in the eastern <br />portion of the proposed permit area, the effective rooting depth ranges from 40- <br />60 inches at the higher elevations and about 24-6D inches at lower elevations. <br />The primary limiting factor for use of these soils is [hat the subsoils are gen- <br />erally clayey, infertile, and have a weak soil structure. Analytical data are <br />presented in Appendix G. <br />Soil reaction (pH) in the proposed mine plan area ranges from slightly acidic (pH <br />6.5) to moderately alkaline (pH 8.2) with [he maiority of the soils being neutral <br />to slightly acid (pH 6.6 to 7.4). The lowest pH's are associated with surface <br />soil horizons as a result of leaching'of bases and organic matter accumulation. <br />The highest pH's are associated with the accumulation of sodium and magnesium <br />salts in subsurface horizons. Some of the soils have gypsum and lime accumula- <br />tions in their subsoils, inherited from parent materials or Leached from surface <br />horizons. The clayey soils that developed on soft shales have slight accumula- <br />tions of lime aad/or gypsum in their substratum. <br />Electrical cond•~ctivity (specific conductance) of saturation extracts of soils <br />within the proposed mine plan area ranges from 0.2 to 2.2 millimhos per centi- <br />meter at 25 de?sees Centigrade. The majority of [he soils are non-saline with <br />electrical cond•:ctivi[ies typically less than 1.0 millimho per centimeter. Soils <br />with saline substratums (E.C. greater than 4.0) that are unsuitable for use in <br />reclamation are very limited in extent within the proposed mine plan area. These <br />unsuitable materials are associated with sodic, clay shales and are distinguished <br />in the field as they occur as grassed small parks in [he otherwise brushcovered <br />landscape. These small grassed parks are included in the broader vegetation type <br />of mountain shr~:~ and big sagebrush/grass and were not delineated on an indivi- <br />dual basis. <br />2-183 <br /> <br />