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8.9 Topsoil Salvage Techniques - Year 2008 and Onward <br />For prime farmland soil, the Lift A material is moved by large dozers to the west of the pit as it <br />advances west. A temporary elongated stockpile of approximately 12.5 feet wide is made along <br />much of the entire north -south distance of the pit. A second temporary elongated stock pile of <br />the Lift B material is made in the same manner which is located immediately east of the Lift A <br />pile. The Bench 1 subsoil is taken directly from the area in advance of the pit using the mine <br />shovel or large front end loaders into large off highway trucks. These trucks will utilize a loop <br />road where most of the material will be directly placed behind the pit in areas that have the <br />lower mine spoil already graded. The Lift B pile is then loaded with the mine shovel or large <br />front end loaders into the same large off highway trucks and dumped in areas that already have <br />the suitable Bench 1 material already graded. It is best for the mine to do direct placement of <br />Lift B and then Lift A. In some cases, this cannot be done and stockpiles must be utilized. The <br />existing and future mine stockpiles are shown on Map 2.05.4 -4. The stockpile locations shown <br />on this map are approximate. The methods of how to determine the stopping point of stripping <br />Lift A, Lift B and the Bench 1 material are described in Section 2.04.9. <br />For non - prime areas, the procedures are basically the same with the only difference being that <br />Lift A and B are combined in a Mixed top lift in the non prime areas. <br />8.10 Stripping Frozen Topsoil <br />The scanned Table 2.05.4(2)(d) -1A from the Natural Resources Conservation Service -Soil <br />Survey of San Miguel Area, Colorado, pg 197 shows the average monthly temperatures from <br />1961 -1990 for Uravan ,Colorado area, which is near Nucla.. It can be seen that the average <br />daily temperatures are above freezing from February through November. The average daily <br />temperature for December and January are only two -four (2 -4) degrees F below freezing so it is <br />believed that the frost line below the ground surface would be minimal and will not penetrate <br />(Revised October 2009) 2.05.4(2)(d) -31 <br />