STATISTICAL EVIDENCE ON THE EFFECTIVENESS OF SEWERING TO PROTECT GROUNDWATER FROM VOC CONTAMINATION

Volatile organic compounds (VOCs) are an important source of contamina tion of groundwater supplies in Massachusetts and many parts of the Un ited States. One local response is to require sewering in wellhead pro tection areas as an easily enforceable policy designed to reduce the p robability of VOC contamination of groundwater. Data were collected fo r 238 wellhead protection areas in Massachusetts on VOC contamination levels and the sewered and unsewered land uses in those aquifer rechar ge areas. Logistic regression procedures were used to see whether sewe ring had any statistical effect on likelihood of contamination of well water. The results provided limited, but not overpowering, support fo r the idea that requiring commercial and industrial land uses to use s ewers would reduce the chance of VOC contamination.