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Dennis Jones Seneca Coal Company Page 2 March 24, 2004 at monitoring site SW-S2-13 during 2003. Observed TDS concentrations for 2003 on Grassy Creek were elevated above the predicted TDS concentrations for monitoring site SW-S2-2. Overall, the TDS plot shows a slightly increasing trend for samples collected from this location. The Division concurs with SCC's findings that the PHC predictions were based on long-term average values. Individual monthly measurements may be affected by climatic conditions and other factors such as relative flows from Sedimentation Ponds 002 and 003. Ten out of nineteen groundwater monitoring wells sampled during 2003 display an increasing trend in TDS concentrations. PHC predictions for groundwater indicate an overall increase in TDS concentrations for the Cow Camp and Bond Creek alluvium located down gradient of sediment pond outfalls 004 and 008. Well SBAL68 located within the Bond Creek alluvium does display an increasing TDS trend, while Well SCAL69 located within the Cow Camp Creek alluvium shows a decreasing TDS trend. The Division has the following specific comments regarding the collection and reporting of surface water and ground water monitoring data contained in the 2003 AHR. 1. In response to DMG comments from the 2002 AHR, SCC will submit a revision in 2004 to make the following changes to the approved monitoring program contained in the permit application package. • Remove Well SWC15 (abandoned and an abandonment report was submitted in 1998). • Add Well SWC10 (drilled in 1979 for water level measurements only in Wolf Creek Coal). • Add Spoil Spring 10A. Please update the approved water monitoring frequency tables accordingly and the Hydrology Monitoring Site Location Map (Exhibit 7-2) contained in the permit document. 2. Well SWU8 has been reported as having an obstructed casing since 1998. If this well is no longer useful, please permanently seal this well and submit an abandonment report to the Division. 3. Table 6 of the AHR shows exceedences of Ground Water Agricultural Use Standards for cadmium and lead. When in fact, the detection limits were elevated by the laboratory for these constituents and the samples were actually none detect for cadmium and lead. It would be more accurate to not list these as exceedences on Table 6. The Division concurs with providing an explanation of the elevated detection limits in the text portion of the AHR when they occur. SCC should continue to work with the laboratory to achieve lower detection limits that are less than or equal to the CDOH standards.