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Map unit 98F (Hap largrids - Endoaqueots association) occurs in natural drainage areas that <br />eventually form shallow valleys on the mesa and on the low lying area near Tuttle Draw. Depth <br />to bedrock varies widely in this map unit. Haplargids with varying depths to bedrock form on <br />drainage side slopes. Endoaquepts are formed where irrigation water has accumulated in <br />drainage bottoms. In a few naturally occurring areas of water accumulation Endoaquolls have <br />formed. <br />Eolian sands are intermixed with Cretaceous Dakota and Burro Canyon Formations in map unit <br />98G (Bowdish - Bowbac complex). Soil is generally moderately deep with significant inclusions <br />of shallow soil on convex slopes. Soil salvage in this map unit may yield slightly less than <br />predicted. <br />Map unit 98H (Wahweap fine sandy loam) occurs on mesa side slopes that are not as steep as <br />those found in map unit 98B. Hardness of bedrock varies depending on the underlying strata. <br />Wahweap soil has the same physical and chemical properties as those soils similarly named in <br />the survey area. Wahweap is outside the range of characteristics compared to the survey area, in <br />that it occurs in an area of 7 inches mean annual precipitation. <br />Table 2.04.9-3 represents average depths and pH of lift layers for soil salvage materials in the <br />1998 survey area. The recommended topsoil salvage depth for each map unit is based on the <br />average of all depth samples taken for the map unit. Appendix 2.04.9-9 lists the percent <br />composition for each soil type in a map unit. Average lift depths are used to calculate volume of <br />salvage material in table 2.04.9-4. Lift layer A is a combination of the following horizons where <br />present: A, Ap, Ag, AB, AC, Bw, and Bt if the pH of those horizon was less than 8.0. Lift layer <br />B is a combination of the following horizons where present: AC, Bw, and Bt if the pH of those <br />horizons was greater than 8.0 and Bk, Btk, and C horizons. The volumes are shown for a) the full <br />thickness reported from the soil survey and also b) 80% or 93% of the thicknesses from the soil <br />survey, depending upon wether the soils are prime or not. For prime soils, a 93% recovery is <br />used. For non -prime soils, an 80% recovery is used. This reduction is used since there might be <br />some rocky areas that exist between sample points, thickness variations that cannot be fully <br />stripped in the field, and other constraints that can occur with large equipment. <br />Table 2.04.9-4 represents the acreage by map unit and the volume (cubic yards)of soil salvage <br />material by lift layer and map available in the 1998 soil survey area and which lies in the <br />disturbance area. The volume is calculated from the acreages and recommended topsoil salvage <br />depth. The recommended topsoil salvage depth for each map unit is based on the average of all <br />depth samples taken for the depth unit. Soil map unit 98B and 98H and all soil units north of BB <br />Road and west of and including the mine pit are combined into one lift layer for all horizons as <br />cited in 2.05.4(2)(d). <br />January 2016 (TR -70) 2.04.9-11 <br />