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the bottom of coal contours used in determining saturated thicknesses were the same contours as the top-of-coal contours for the overburden unit. The bottom-of-coal contours were remapped correctly. Also, the days in water used in the original pit pumpage Theis drawdown calculations were per pit rather than for the year. All Theis drawdowns for the five- year mining block, as well as the life-of-mine were recalculated using the correct number of days in water each year and the new yearly pit inflow volumes in the case of the Wadge coal calculations. d. The length in water and days in water (Tables 17-2 through 17- 5) are presented on a per pit basis. Annual numbers can be obtained by multiplying the values by the number of pits specified for a given year. Pit area in water as presented in Attachment 17-3 is per pit. e. This discrepancy was resolved during the February 1, 1995 meeting in Denver. The Fax copy CDMG was using had a smudge which made the storage coefficient appear to be .00027 rather than .00021, which was the correct storage coefficient to use for the Wadge coal. f. The equation was the inverse of what it should be. Instead of solving for "t", a "t" equal to the maximum number of days in water (highest pit inflow year) for each geologic unit contributing to pit inflow was used. The pit pumpage drawdown calculations incorporating these "t's" and maximum annual pit • inflow values are presented in Attachment 17-3. The equations presented on Page l0 have been revised to incorporate these changes. g. See response to question 56 above. The potentiometric surface map of the overburden (Exhibit 7-2) can be overlain on the top of coal contour map (Exhibit 6-2) to calculate wet areas and saturated thicknesses in the overburden. The potentiometric surface maps of the Wadge and Wolf Creek coal units can also be overlain on Exhibit 6-2 to calculate wet areas and saturated thicknesses in the coal units. An average Wadge coal thickness of 13.5 feet should be subtracted from the top of coal elevations on the Grassy Creek side. Wadge coal thicknesses ranging from 7.5 to 10.8 feet should be subtracted from the top of coal elevations on the Sage Creek side. An average Wolf Creek coal thickness of 17 feet should be subtracted from the top of coal elevations in the Wolf Creek pit. The coal and overburden thicknesses, as well as saturated thicknesses for each year of mining, are presented in Attachment 17-2. 58. The locations of two small stock tanks noted by CDMG have been added to revised Exhibit 16-1, Tab 16, Volume VIII of the PAP. In addition, SCC has revised minor portions of the "Water Rights and Alternative Water Supplies" section of Tab 16 to address these unrighted stock tanks. Finally, the "Removal of Wells and Ponds by Mining" section and Table 17-22 of Tab 17, • Volume VIII of the PAP have been modified to address potential impacts to these two ponds. 15