No Pruging Ground-Water Sampling Proposal for Gasoline Compunds in New Jersey Unconfined Aquifers

摘要

Recent studies have reported that the ground-water sampling technique of "no puge' produces similar results when compared to traditional well purging methods for pertroleum hydrocarbons. Whether no purge sampling produces a more representative ground-water sample and how purging techniques can adversely impact final sample results have been the topics of much controversy in the scientific community. Regulators in select states have approved no puge sampling and in New York this method has been used since 1996 with no negative implicatins. Therefore, to further evaluate no purge sampling and propose applying this sampling method in New, Jersey, 21 sites in New Jersey, New York and Connecticut were sampled ot determine the sensitivity of purging for routine sampling of petroleum hydrocarbons. Over 200 ground-water samples wee collected before and after traditional well puging procedures. Ground-water samples were laboratory analyzed for benzene, toluene, ethylbenzene, xylenes, and methyl tertiary butyl ether (MTBE). All monitoring wells tested were completed in shallow unconfined aquifers with well screens that extended across the water table. Statistical analysis of these results demonstrated a strong correlation between the no puge and puged samples. From these findings, no puge sampling procedures are proposed for sites in New Jersey when routine well sampling is required.