OCCURRENCE AND FATE OF ORGANIC-SOLVENT RESIDUES IN ANOXIC GROUNDWATER AT THE GLOUCESTER LANDFILL, CANADA

The disposal of organic chemicals in trenches at a waste disposal site near Ottawa, Ontario, Canada, has resulted in the contamination of the underlying aquifer. The organic residues measured in groundwater samples are reported and the mechanisms of contaminant transport in the aquifer discussed. Groundwater samples from monitoring wells and multilevel samplers were analysed by gas chromatography-mass spectrometry. Ultratrace quantities of chlorinated dibenzodioxins and furans were found in groundwaters directly beneath the trenches. A wide variety of volatile compounds were identified and quantitated in samples from the aquifer. The compound of greatest concern was 1, 4-dioxane, because of its toxicity and mobility, while that present in greatest concentration was a Freon, F113, which appeared to be very persistent, although three transformation products were identified. © 1990, American Chemical Society. All rights reserved.