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<br />-29- <br />The climate of the proposed permit area is characteristic of continental <br />intermountain regions. Typically, the area experiences cold winters, hot <br />summers, low rainfall and short growing seasons. The Twin Pines No. 2 Mine <br />receives approximately 14 inches of precipitation which primarily falls <br />between April and September. Predominant winds in the area are from the west. <br />The Division finds the application is in compliance with the requirements of <br />this section. <br />X. Topsoil - Rules 2.04.9, 2.05.3(5), 2.05.4(2)(d) and 4.06 <br />Baseline soils information is found in Section 2.04.9, pages 53 through 59-N, <br />Volume I of the permit application. Soils information is also provided by a <br />soils map (page 55). Drawing No. 1 - Great Divide Engineering "Twin Pines No. <br />2" Area Topography - also indicates soils types as well as areas of previous <br />disturbance and soils sample locations. Drawing No. 4 (TP-3) shows the areas <br />of disturbance, the permit boundary and the location of the proposed topsoil <br />stockpile. Topsoil stripping is discussed on page 81 (revised) of Volume 1 in <br />the application. Reclamation is discussed in pages 86 through 88 of Volume 1. <br />Of the 9.75 acres of area to be disturbed during the proposed operation less <br />than 0.5 acres is currently undisturbed. The remainder of the proposed site <br />has been previously disturbed by surface strip mining. <br />d <br />Soil samples of the distur ed area material show it to be acceptable growth <br />medium for re vegetation. The texture of this material ranges from loam to <br />sandy clay loam. Sodium orption ratios range form 0.34 to 0.67, <br />Electroconductivity from 0.32 to 3.4 and pH's from 5.4 to 8.0. The main <br />limiting factor is a high percentage of 1 mm to 3" rock fragments. Since a <br />large portion of these fragments are shale chips, the Division expects some <br />breakdown to finer material in a relatively short time, improving the quality <br />of the plant growth medium. <br />`The undisturbed soils within the proposed disturbed areas were mapped as minor <br />inclusions of the Louviers-Travessilla complex, 20 to 50 percent slopes (page <br />59B). The texture of these soils ranges from clay to very fine sandy loam. <br />Since the "A", "C" and "2C" horizons will be stripped as one unit the mixing <br />of these horizons will add coarser materials from the "A" (clay loam) and "2C" <br />(very fine sandy loam) to the "C" (Clay) horizon, resulting in topsoil with an <br />acceptable texture. Other parameters tested included pH, available water <br />capacity, SAR, EC, sodium, magnesium, calcium and acid potential. None of <br />these factors indicated any potential problems with using this material for <br />r~evegetation purposes. <br />~ Topsoil will be stripped from two areas. The first is in the area of a <br />proposed ramp which will lead to the mine development waste disposal area <br />(page 81-revised). The ramp is a permanent fill fora previously mined <br />contour strip. The proposed area to be stripped is about 20 feet by 300 feet <br />long. The topsoil will be placed on the sides of the ramp and re vegetated. <br /> <br />