AWWA JAW71680

Although numerous instances of permeation involving polyethylene (PE) pipes have been reported, information obtained from permeation incidents typically has been sparse, qualitative, and incomplete, and few data are available to predict permeation behavior in the field. This study simulated permeation of benzene, toluene, ethylbenzene, and xylene compounds into potable water in high-density polyethylene (HDPE) pipes from gasoline-contaminated groundwater and gasoline- contaminated unsaturated soil. The authors also determined permeation rates and diffusion coefficients necessary for developing empirical equations to predict permeation behavior under contamination conditions typically encountered in the field. Results indicated that PE pipes should not be used for drinking water conveyance in gasoline- contaminated sites because pollutants can pass rapidly through the pipes and enter the distribution system. For practical purposes, there is no level of contamination at which PE pipe is resistant to permeation by petroleum- based aromatic compounds. In the event of a gasoline spill in the vicinity of a PE service line, corrective action should be taken immediately. Includes 20 references, tables, figures.