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Three wells are used to monitor spoil water quality (GW-s25-s, s26- s, s27-s) above the Wadge Impoundment in the northern portion of the permit area and display a MgCa-504 type water with reduced TDS concentrations at s27, the lowest downgradient well (probably due to dilution). Two wells are used to monitor spoil water quality in the Cow Camp Creek area (s61, s62) and display CaMg-504 type water with TDS values increasing slightly at s62. Wells are located in the three alluvial systems around Seneca II. Wells 31-A and 32-A in the Little Grassy Creek alluvium display CaMg-S04 type water. We should note that Peabody committed to "monthly monitoring" for field parameters at both 31-A and 32-A in 1982. Monthly field parameter monitoring was discontinued at these sites since the 1988 AHR and no explanation given. Both Cow Camp and Bond Creek (tributaries of Trout Creek on the Western side of the Tow Creek anticline) alluvium have a naturally high occurrence of salts as evidenced by high TDS concentrations prior to mining. Well GW-s46-A on Cow Camp alluvium displays a MgCaNa-S04 type water and has experienced decreasing TDS values since 1986 (3498 mg/1) to a low of 2320 mg/1 in June of 1991. Well GW-s69-A, completed in 1989 downstream of s46 displays a CaMg-SO4 type water with TDS values markedly greater than those upstream at s46. This phenomenon is probably a result of the naturally high salt concentration in the Cow Camp Creek alluvium. Well GW-s68-A, also completed in 1988, similarly displays a CaMg- S04 type water and averaged over 5,000 mg/1 TDS in 1991 rendering the water unacceptable for even livestock watering. The average 1991 TDS, measured at NPDES 008 upstream from s68, of 1367 mg/1 indicates that local alluvial geochemistry is probably responsible for the large increase and not Seneca II mining activities. We should note that due to low transmissivity and permeability in these alluvial systems that groundwater flows at rates of .13 and .15 ft/day for Cow Camp Creek and Bond Creek respectively thereby rendering impacts on Trout Creek alluvium several miles away as irrelevant (at least for 200-300 years). Randy Pierce commented (7/13/92) that similar low average groundwater flow values are not uncommon for alluvial environments high in silts and clays which experience high evapotranspiration and ephemeral surface flow conditions. The 9-10.5 feet thick Wadge coal seam aquifer is monitored by wells GW-517-W and GW-s19-W, data from which may be compared to baseline, pre-mine data from the original permit at well GW-s40. The attached graph showing Electrical Conductivity (EC), TDS, and Sodium concentration trends show a marked increase in these parameters since 1980. We should note that GW-s17-W is in direct communication with the Wadge impoundment spoils water. Never the less, Peabody's statement on page 10, paragraph six, "Mining at Seneca II is not believed to be causing the degradation of any monitored aquifer" may be misapplied.