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3.5.2 <br />• The analysis parameters that were tested for include: pH; <br />electrical conductivity (EC); soluble Ca, Mg, Na; sodium adsorption <br />ratio (SAR); saturation percentage; organic matter (OM); and <br />particle size. <br />As part of the quality assurance program, duplicate samples were <br />submitted for analysis as well as a sample that the CSU Soil <br />Testing Lab analyzed in the past as part of a federal program to <br />check on and possibly standardize lab analysis methods. The <br />results of these comparative analyses were favorable (Table 3.5-3). <br />In general, the lab analyses results indicate that the site soils <br />are chemically suitable as a topsoiling material. The normally <br />accepted suitability limits for each parameter (Table 3.5-4) were <br />referred to in order to make this determination. Because the <br />chemical composition of the sampled soils are suitable, the <br />physical nature of the soils (i.e., amount of rock fragments) <br />becomes the limiting factor that determines suitability. <br />During the 1994 midterm review, the Division questioned the results <br />of the lab analyses for the Heldt soil type. Table 3.5-1 indicates <br />this soil type has 518 to 548 clay content whereas Table 3.5-2 <br />• indicates a clay content of 288 to 318. The SCS Soil Survey of the <br />Rifle, CO area was used to bring another set of numbers into the <br />discussion. According to this survey the Heldt soil type has a 308 <br />to 458 clay content at a depth of 0 - 8" and a 358 to 458 clay <br />content at a depth of 8" to 60". The Operator recommends the use <br />of the SCS percent clay data because it is representative of a wide <br />range of samples and the percent clay values fall between the <br />values presented in Tables 3.5-1 and 3.5-2. <br />3.5.4 Topsoil Volume Calculation <br />Thirty-five percent coarse fragments by volume was used as the <br />cutoff between suitable and unsuitable material. Based on this, <br />Table 3.5-5 exhibits the salvageable soil depths on the surface <br />facilities area. The acreages of the various soil types are also <br />listed in Table 3.5-5. <br />Topsoil volumes were then calculated by multiplying the salvageable <br />depth times the acreage for each soil type. Minimum, maximum, and <br />average salvageable volumes were calculated by utilizing the high, <br />low, and average of the depth range for each soil Because the <br />actual depth that will be encountered will be variable. Table 3.5- <br />5 exhibits the topsoil volumes that are available for the surface <br />. facilities area. <br />wcic -coal Ridge No. i 3-58 06-07-95 <br />