Leaching of Tetrachloroethylene from Vinyl‐Lined Pipe

Abstract

Tetrachloroethylene has been used in the manufacture of vinyl‐lined asbestos cement pipe installed in water distribution systems in certain New England communities. Tetrachloroethylene was used as a solvent for Piccotex, a vinyl‐toluene α‐methyl styrene co‐polymer, which was then sprayed on the interior of the finished asbestos cement pipe. The migration of tetrachloroethylene through the vinyl lining was modeled as a diffusive process in which the diffusion coefficient was an exponential function of concentration. The parameters of the model were found by fitting a numerical solution of the diffusion equation to data from laboratory experiments involving the evaporation of tetrachloroethylene from a Piccotex layer. The conclusion was reached that significant quantities of tetrachloroethylene may be leached into the water supply for a time period on the order of years.