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Michael G. Altavilla Seneca Coal Company Page 7 November 24, 1998 wells located within the II-W South area (GW-S2W-4OV1, GW-S2W-4W, GW-S2W- 40V2, and GW-S2W-4WC). There does not appeaz to be any baseline water quality data provided for the overbtrden aquifer (wells 4OV 1 and 4OV2). On revised page 147 of Tab 7, SCC states that these two wells are not used as water quality monitor wells, however, revised page 15-3a-3 indicates that these wells will be utilized for semiannual water quality monitoring. Please provide an explanation for this discrepancy and provide rationale for the apparent lack of monitoring data for the overburden aquifer. 24. There aze no alluvial monitoring wells within the II-W South area. There is no discussion or baseline data provided for Hubberson Gulch alluvium above well GW-S2W-6A2. An upstream portion of Hubberson Gulch flows through the II-W South azea, and discharges from proposed Ponds 016 and 017 may directly impact the quantity and quality of the Hubberson Gulch alluvial aquifer upgradient of well 6A2. Please provide an explanation and/or rationale for the lack of alluvial groundwater monitoring data in proximity to the II-W South area. 25. Baseline water quality data were provided for the Wadge Coal and the Wolf Creek Coal in the II-W South area. However, data were not provided for the Trout Creek Sandstone aquifer. Does SCC intend to monitor the Trout Creek Sandstone in the II-W South area? Please provide an explanation of SCC's rationale for monitoring or the lack of monitoring beneath the lowest coal seam to be mined in the II-W South area. 26. It appears that monitoring wells 4OV 1, 4W, 4OV2, and 4WC are located in very close proximity to the proposed pit boundary in the II-W South azea. Will any of these wells be impacted or removed by mining? If so, please provide the Division with a contingency plan for replacement of these wells if they become inoperable or removed by mining. 27. Surface water monitoring site SW-S2W-SG9 provides the only upstream monitoring point on Hubberson Gulch above any mine disturbance. This site has been initially sampled for water quality and flow, but has not been included in the current hydrologic monitoring program (Table 1, page 1 ~-3a-2). The Division believes that this is an important monitoring location for comparative analysis with monitoring locations down gradient of disturbed areas. Please consider adding this location to the current monitoring program for monthly dischazge measurements and semiannual water quality analysis. If appropriate, please revise Tabs 7 and 15 accordingly. 28. Please check the calculations on Table 17-31, and make corrections if deemed appropriate. In particular, the estimated pit inflow for the year 2001 in both the Wadge Overburden aquifer and the Wadge Coal aquifer appear to be high/over estimated.