ABSTRACT
Groundwater contamination case studies provide an appreciation for the range of release modes and contaminant behavior one might expect to encounter at different contamination sites. The rate of migration of 1,4-dioxane relative to that of chlorinated solvents is among the more interesting attributes of this contaminant. Migration rates refl ect both the higher mobility of 1,4-dioxane and its refractory nature relative to methyl chloroform because 1,4-dioxane is miscible and resistant to biodegradation and abiotic degradation. Will 1,4-dioxane be fl ushed out of the aquifer by fl owing groundwater and diluted to inconsequential concentrations? Should one expect to fi nd a substantial mass of residual 1,4dioxane near the point of release, withheld in the fi ne-grained pores of silts and clays? What conditions support persistence of 1,4-dioxane such that the quality of drinking water is degraded? The answers to these questions are helpful for planning site characterization at 1,4-dioxane release sites.
