It has long been known that organic contaminants may permeate through plastic pipes and adversely affect the quality of drinking water in a distribution system (Vonk, 1985; Thompson and Jenkins, 1987). The plastic pipe materials involved include polybutylene (PB), polyethylene (PE) and polyvinyl chloride (PVC) and the contaminants of interest include highly volatile hydrocarbons and chlorinated organic solvents (Holsen et al., 1991a). In this study, the permeation of petroleum-based aromatic compounds (BTEX) through PE pipe was investigated under simulated field conditions, including subsurface gasoline spills and gasoline-contaminated groundwater with varied levels of contamination. Most of the pipe permeation incidents reported were related to petroleum products, mainly gasoline spills or leaks (Holsen et al., 1991a). The effects of soil organic matter content on permeation were also examined. The main purpose of this study was to develop empirical equations which can be used to predict the permeation behavior of BTEX through PE pipe at contaminant levels typically faced in the environment. Includes 8 references, table, figures.