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16.6 Stripping Frozen Topsoil <br />The scanned Table 2.05.4.9 -10 shows the average monthly temperatures from 1961 -1990 for <br />Uravan ,Colorado area, which is near Nucla, from the Natural Resources Conservation Service -Soil <br />Survey of San Miguel Area, Colorado, pg 197. It can be seen that the average daily temperatures <br />are above freezing from February through November. The average daily temperature for <br />December and January are only two -four (2 -4) degrees F below freezing so it is believed that the <br />frost line below the ground surface would be minimal and will not penetrate through the Prime <br />Farmland Soil Lift A horizon. The only concern one would ever have is the operational possibility <br />of pulling up chunks of frozen Lift A and B topsoil together with equipment because of the frost. <br />One wouldn't want to dilute topsoil Lift A with big chunks of topsoil Lift B. For a single lift topsoil <br />removal or a mixed topsoil stripping situation, then that concern goes away. It should be noted that <br />New Horizon stacks Lift A, Lift B and Mixed topsoil into separate but large piles with a dozer. The <br />larger the topsoil pile, the more dirt insulation there is protecting the interface to Lift B directly under <br />the pile. The conclusion is, that stripping (dozing, load, haul, dump, and regrading) topsoil in <br />freezing conditions is perfectly acceptable at the New Horizon Mine. By the rare chance there is <br />a micro occurrence of an extremely sub freezing period of time, for many weeks, the actual rip, <br />doze and stacking of any Lift A will be curtailed but stacking of Lift B or Mixed topsoil could <br />continue. Finally, there would be a high probability the dozer(s) wouldn't be able to start or operate <br />under those extreme freezing conditions anyway. <br />16.7 Stripping Saturated Topsoil <br />The scanned Table 2.05.4(2)(d) -10 from the Natural Resources Conservation Service -Soil Survey <br />of San Miguel Area, Colorado, pg 197 shows the average monthly precipitation from 1961 -1990 <br />for Uravan ,Colorado area, which is near Nucla. The monthly average ranges from 0.62 " - 1.53" per <br />month. The yearly average is only 12.60" of precipitation per year. WFC just doesn't see a problem <br />with the ground getting saturated beyond a couple inches by rainfall, at any one time. The average <br />snowfall per month as seen in Table 2.05.4(2)(d) -10 is also insignificant for the Nucla area. As <br />mentioned above, Lift A, Lift B and Mixed topsoil will be piled up using a dozer. So after the dozer <br />gets past the first couple of inches, if that, of rain soaked topsoil, he will be in the dry. No <br />(Revised July 2010) 2.04.9 -39 <br />