I have include included the maximum allowable concentration in the third column for each compound for comparison. The fourth column shows a multiple for each compound's test result above the 2L state standard. North Carolina sets public health standard for 88 chemical compounds in groundwater. The best usage for groundwater is considered to be for drinking water. The highest result for each compound detected is shown.
Some compounds show increases, some show decreases.
Fractured bedrock at the site and groundwater travel are two factors which affect concentrations of these compounds. Also, some organic compounds break down over time and are metabolized, becoming new compounds. This is typical of organic contaminants undergoing anaerobic change in landfills. Some of these new compounds, such as vinyl chloride, are more hazardous to human health than their precursors. Finally, Table 3 contains state test results for two toxic compounds regulated by North Carolina which are below the maximum state standard but which show a increasing trend over the last four sampling events.