An evaluation of the effects of well construction materials and ground-water sampling equipment on concentrations of volatile organic compounds

In 1985, the Pacific Northwest Laboratory conducted a study on ground-water samples collected from the 300 Area of the Hanford Site, which is located in southeastern Washington. The purpose of the study was to evaluate how well construction materials and ground-water sampling equipment affect measured concentrations of volatile organic compounds on the ground water. Ground-water samples were collected in an area of known contamination from two monitoring wells. Sampling was conducted for a total of 4 weeks using three dedicated sampling devices. Each sample was analyzed for volatile organic content by gas chromatography with electron capture detection. The data were statistically analyzed to ascertain differences in concentrations of contaminants resulting from well construction materials and ground-water sampling equipment. No statistically significant differences in concentrations of volatile organic compounds were found resulting from the well construction materials and ground-water sampling equipment. Analyses indicate a correlation between constituent concentration and sample date and, to a lesser degree, water table elevation. The range in concentrations during the study was greater than the differences caused by the two wells and three sampling devices. 4 refs., 10 figs., 5 tabs.