DIFFUSION SAMPLERS AS AN INEXPENSIVE APPROACH TO MONITORING VOCS IN-GROUND WATER

Diffusion samplers installed in observation wells were found to be cap able of yielding representative water samples for chlorinated volatile organic compounds. The samplers consisted of polyethylene bags contai ning deionized water and relied on diffusion of chlorinated volatile o rganic compounds through the polyethylene membrane. The known ability of polyethylene to transmit other volatile compounds, such as benzene and toluene, indicates that the samplers can be used for a variety of volatile organic compounds. In wells at the study area, the volatile o rganic compound concentrations in water samples obtained using the sam plers without prior purging were similar to concentrations in water sa mples obtained from the respective wells using traditional purging and sampling approaches. The low cost associated with this approach makes it a viable option for monitoring large observation-well networks for volatile organic compounds.