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O initial thickness of 0.8 for the thin overburden and 1.2 for thick overburden brackets all expected <br />situations at the Trapper Mine. <br />In reference to thin overburden, the condRions a[ Trapper Mine that could come closest to satisfying the <br />criteria are forty et of overburden and thirteen feet of coal. Percent swell at the Trapper Mine is <br />approximate 25°'0 <br />Ratio = 40 X 1.25 = 0.94 > 0.8 <br />40+13 <br />In reference to thick overburden, the conddions that would come closest to satisfying the criteria are 80 <br />feet of overburden and 4Ya feet of coal. <br />Ratio=80X1.25=1.18<1.2 <br />80 + 4'/z <br />When ash is disposed of in the pit, the depth of ash in a particular pit will be such that the ratio of final <br />totalthickness of ash and spoil to initial thickness of coal and overburden will no[ exceed 1.2. <br />Excess Spoil <br />As discussed previously, there will be no thick or thin overburden experienced at this site. Also, boxcut <br />material generated during the permit period is not considered excess spoil (refer to Section 3.5.4) and <br />can be used where rt occurs to achieve the approximate original contour. <br />Spoil Fires <br />Large spoil fires are not anticipated and a specific contingency plan for spoil tires is not needed. History <br />at the Trapper Mine indicates that occasional spot! fires do occur at this site but are very small in size. <br />When one occurs, a dozer is used to extinguish the fire. <br />' RR- 3.- __ _ -------- <br />3-49 I~ itr~VISION APPROVED <br />i (~ArE /-/9-93 _ <br />I ~ --- ----..... <br />