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16.6 Stripping Frozen Topsoil <br />The scanned Table 2.04.9 -10 shows the average monthly temperatures from 1961 -1990 for Uravan <br />,Colorado area, which is near Nucla, from the Natural Resources Conservation Service -Soil Survey <br />of San Miguel Area, Colorado, pg 197. It can be seen that the average daily temperatures are <br />above freezing from February through November. The average daily temperature for December <br />and January are only two -four (2 -4) degrees F below freezing so it is believed that the frost line <br />belowthe ground surface would be minimal and will not penetrate through the Prime Farmland Soil <br />Lift A horizon. The only concern one would ever have is the operational possibility of pulling up <br />chunks of frozen Lift A and B topsoil together with equipment because of the frost. One wouldn't <br />want to dilute topsoil Lift A with big chunks of topsoil Lift B. For a single lift topsoil removal or a <br />mixed topsoil stripping situation, then that concern goes away. It should be noted that New Horizon <br />stacks Lift A, Lift B and Mixed topsoil into separate but large piles with a dozer. The larger the <br />topsoil pile, the more dirt insulation there is protecting the interface to Lift B directly under the pile. <br />The conclusion is, that stripping (dozing, load, haul, dump, and regrading) topsoil in freezing <br />conditions is perfectly acceptable at the New Horizon Mine. By the rare chance there is a micro <br />occurrence of an extremely sub freezing period of time, for many weeks, the actual rip, doze and <br />stacking of any Lift A will be curtailed but stacking of Lift B or Mixed topsoil could continue. Finally, <br />there would be a high probability the dozer(s) wouldn't be able to start or operate under those <br />extreme freezing conditions anyway. <br />16.7 Stripping Saturated Topsoil <br />The scanned Table 2.04.9 -10 from the Natural Resources Conservation Service -Soil Survey of San <br />Miguel Area, Colorado, pg 197 shows the average monthly precipitation from 1961 -1990 for Uravan <br />,Colorado area, which is near Nucla. The monthly average ranges from 0.62 " - 1.53" per month. The <br />yearly average is only 12.60" of precipitation per year. WFC doesn't see a problem with the ground <br />getting saturated beyond a couple inches by rainfall, at any one time. The average snowfall per <br />month as seen in Table Table 2.04.9 -10 is also insignificant for the Nucla area. As mentioned <br />above, Lift A, Lift B and Mixed topsoil will be piled up using a dozer. So after the dozer gets past <br />the first couple of inches, if that, of rain soaked topsoil, he will be in the dry. No significant problem <br />Revised September 2010 (PR 06) 2.04.9 -41 <br />