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<br />calculated using the following assumptions: all excess spoil <br />material was swelled by 15 percent; all excess material from <br />within the pit was not swelled, the 20 percent swell of in-place <br />overburden is virtually offset by the removal of the excavated <br />coal volume assuming the 5.5:1 overburden to coal ratio given by <br />the applicant is correct; and excess overburden from outside the <br />pit was swelled by 20 percent. The difference between the volume <br />of material available for backfill and the volume of material <br />necessary to achieve the postmining contours was calculated to be <br />approximately 05,000 fill cubic yards (FCY). The discrepancy <br />between this volume and the volume given on Figure 2A, 34,000 <br />FCY, is probably due more to the errors inherent in planimetering <br />rather than to errors in calculation by the applicant or the reg- <br />ulatory authority. A difference in the material available from <br />the stockpile area was noted; available stockpile material is <br />noted as 1,208,000 CY on Figure 2A, available stockpile material <br />was calculated by the reviewer to be 1,334,000 CY. However, even <br />with this discrepancy, the relatively close agreement concerning <br />excavated and backfilled volumes indicates that the proposed <br />reclaimed contours for Pit 1 can probably be achieved. <br />It is not known how the volumetrics for Pit 2 given on Fig- <br />ure 2A, and Table 2, of Addendum II were calculated. As noted <br />before, the excavated overburden volumes shown on Figure 2A and <br />Table 2 do not match. To determine the difference in total <br />material excavated and total material backfilled based on the <br />numbers shown un Figure 2A, 910,000 tons of coal were assumed to <br />be excavated from Pit 2. Using this number, the total BCY of <br />material to be excavated was determined to be 6,024,000 BCY. <br />Phis gave a difference between excavated and backfilled volumes <br />of 379,000 CY for Figure 2A. The difference in excavated and <br />t~ackfilled volumes in Pit 2 based on Table 2 was calculated to be <br />300,000 CY. <br />By planimetering the difference in the premining and <br />proposed reclaimed contours as shown on Figure 2A the volume <br />difference for Pit 2 was calculated. This difference in volume <br />-55- <br />