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1 As indicated in Tables 3 and 6, no organic compounds were detected in either the ground water or vadose zone soil at concentrations that exceeded the DHS hazardous waste (STLC and TTLC) criteria. As indicated in Tables 4 and 7, no metals concentrations exceeded DHS hazardous waste criteria (STLC and TTLC) in the ground -water or vadose zone soil samples. The concentrations of manganese in monitoring wells MW -1, MW -3, MW -4, and SB -1 exceeded the DHS secondary drinking water standard of 0.05 mg/1. However, the manganese concentration appears to be naturally elevated in both the deep and shallow aquifer because concentrations exceeding DHS standards were present in both upgradient and downgradient wells. As indicated in Table 5, the concentrations of conventional water quality parameters in the deep regional aquifer were within the DHS drinking water standards with only one exception. TDS concentration was 1,200 mg/l in the deep upgradient well MW -2, which exceeds the DHS drinking water standard of 1,000 mg/l. The concentrations of conventional water quality parameters in the shallow perched aquifer were within the DHS drinking water standards for shallow wells MW -5 and SB -l. However, the concentrations of EC (2,600 umhos/cm), sulfate (700 mg/1), and TDS (1,800 mg/1) in the shallow downgradient well MW -4 exceeded the DHS secondary drinking water standards of 1,600 umhos, 500 mg/l, and 1,000 mg/l, respectively. These results indicate that the deep regional aquifer is of good quality. As would be expected, the perched aquifer exhibits higher concentrations of several naturally occurring constituents and is of somewhat lower quality. 4.4 CONCLUSIONS Analysis of the samples collected during the SWAT Program indicates that no compounds are present in the shallow perched and deep regional aquifers, or in vadose zone soils at levels exceeding hazardous waste criteria. Based on the data collected during the SWAT Program, the landfill does not appear to be impacting the deep regional aquifer. One of the monitoring wells in the shallow perched aquifer exhibits somewhat higher concentrations of a few conventional water