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surface information was supplemented with average 2001 ground water level elevations measured in Seneca II-W South area monitoring wells and historic information from South area coreholes. The saturated thicknesses of the overburden units were estimated to be 35 feet for the Sage Creek overburden, and 58 feet for the Wolf Creek overburden. Water level data and the lithologic log from well WSOV24, as well as lithologic logs from coreholes 1916, 4216, 4756 and 7646 were used to calculate the saturated thickness of the Sage Creek overburden. Wells WWCOV24, WWC3, WWU3E and WWC4, completed down dip of the proposed Sage Creek/Wolf Creek mining area, were used to calculate the saturated thickness of the Wolf Creek overburden. The saturated thickness values for the coal seams were assumed to be equal to the average seam thickness; this methodology is consistent with the original permit. The average Sage Creek coal seam was calculated to 4.4 feet (see Tab 6, App. 6-11. The Wolf Creek coal saturated thickness value was calculated to be 26 feet. Table 17-30 summarizes aquifer characteristics values used in the Darcy analysis. The original permit included overburden and coal aquifer characteristics for the Wadge ground water system. Several Seneca II-W monitoring wells included in the original permit had aquifer test results for the Wolf Creek ground water system. Where possible, Seneca II-W aquifer test results were used to define the Wolf Creek aquifer characteristics. SCC has not conducted aquifer tests on the Sage Creek ground water system at Seneca II-W. The Yoast Mine permit, however, includes aquifer characteristics for the Wadge underburden; this unit is equivalent to Sage Creek overburden. It has been assumed that the Yoast Mine Wadge underburden characteristics are representative of Sage Creek overburden characteristics at the Seneca II-W South area. Where aquifer test results are not available le.g., Sage Creek coall, the most liberal values that SCC calculated in the existing permit were used. While this may not represent actual aquifer characteristics, this method provides a conservative worst-case-scenario. Mean values for hydraulic conductivity from the Seneca II-W area were used in the Wadge and Wolf Creek analyses. The hydraulic conductivity value for Wadge underburden from the Yoast Mine was assumed to be characteristic of Sage Creek overburden. The Sage Creek coal hydraulic conductivity was conservatively assumed to be similar to the Wadge coal hydraulic conductivity value. The hydraulic gradient values were calculated from the potentiometric surface maps of the water-bearing units. Storativity values calculated from aquifer tests within the overburden units in the Seneca II-W area (Wadge units) range from 10-2 87 Revised 1/02