Migration of dilute aqueous organic pollutants through HDPE geomembranes

The migration of the dilute aqueous organic contaminants through HDPE geome mbranes is examined. Semi-empirical methods to estimate partition and diffu sion coefficients for organic contaminants in dilute aqueous solutions with respect to high-density polyethylene (HDPE) geomembranes are proposed. The se methods were evaluated by performing sorption and diffusion tests on a 2 .0 mm thick HDPE geomembrane using three chlorinated hydrocarbons (dichloro methane. 1,2-dichloroethane and trichloroethylene) and four aromatic hydroc arbons (benzene, toluene, ethylbenzene and xylenes). The results show that the partition coefficient (S-gf) can be fairly well estimated using the met hod based n-octanol/water coefficient of the contaminant and even better by that based on the chemical molecular weight. This suggests that these meth ods may be used as starting point to estimate the migration of organic cont aminants through HDPE geomembranes. (C) 2001 Elsevier Science Ltd. All righ ts reserved.