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IV. Topsoil <br />Information dealing with baseline soil characteristics and depths available for reclamation <br />in the portion of the operation located in Munger Canyon are located in Sections 2.4, 3.2, <br />3.4 and 4.7 of Volume I of the application. Baseline soil information and salvage and <br />redistribution plans for the central facilities area and coal processing waste disposal area <br />can be found in Sections 2.5, 3.1, and 4.4 of Volume VI and on Figures 2.5-1 s and 4.4-2s <br />of Volume VII of the application. <br />No topsoil was stripped prior to the disturbance which presently exists at the mine. <br />Construction of the road consisted primarily of widening an existing farm road and <br />cutting into a steep sideslope. This extension of the road, as well as development of the <br />existing face-up occurred in an area of thin soils along steep slopes. A combination of <br />these steep slopes and thin soils made topsoil salvage difficult. <br />Soils were mapped at an order I to II level of intensity in the azea to be disturbed and <br />order III in other proximate areas (see Figure 4.7-2, Volume II and Table 4.4-2s Volume <br />VI of the application). These soils were classified to the series and subgroup level, <br />respectively. <br />The soils which will be disturbed by the proposed operation include Billings saline <br />complex, Fru.ita sandy loam, Glendive loam, Havre loam, Nihill loam, Rivra gravelly <br />loam variant and Torriorthent rock outcrop complex. These soils range from loam to <br />sandy loam texture. Values for pH range from 7.2 to 9.0, with the higher value occurring <br />below 33 inches in the Billings saline complex. Sodium adsorption ratios (SAR) ranged <br />from .2 to 57.3 with the higher SAR in the Havre loam below a depth of 8 inches. Boron <br />was measured and ranges from .1 to .7 mg/1. <br />Grand Valley Coal Company proposes stripping anywhere from 12 to 36 inches of topsoil <br />from disturbed azeas, depending on the soil type encountered. The steep slopes and thin <br />nature of the Torriorthent soils will prohibit stripping in some cases. No topsoil will be <br />stripped from. azeas previously disturbed. <br />Table 4.4-8s of Volume VI of the permit application indicates that a total of 105.7 acre <br />feet of topsoil will be salvaged from azeas proposed for disturbance along East Salt Creek <br />under the proposed central facilities azea permit revision. Topsoil replacement operations <br />will result in an average soil replacement depth of 18 inches over regraded, <br />non-agricultural azeas. Agricultural lands identified for disturbance (2.9 acres) will be <br />retopsoiled to a depth of 24 inches. <br />It is projected. that approximately six acre-feet of topsoil will be stripped from all areas to <br />be disturbed within Munger Canyon. This volume will be sufficient to replace topsoil <br />over l2 to 18 acres of disturbance to a depth of 4 to 6 inches. This replacement depth <br />37 <br />