Distribution of Trichloroethylene in Air, Soil and Groundwater around a Metalware Factory.

Abstract

Concentrations of trichloroethylene (TCE) in air, soil and groundwater were measured around a metalware factory, where TCE was used for degreasing and cleaning of metalware. The mean level of TCE exhausted from the cleaning system through the stack at the factory was 360 ppm at the operating system or 130 ppm at the stand-by system, and was estimated to 30% of TCE used at the factory ; most residual of the used TCE (70%) was introduced into air through ventilators. TCE exhausted from the factory to the air was diluted rapidly, and TCE concentration in air decreased as the distance from the stack lengthened on the leeward. Some of TCE in air was supplied to soil within at least 400 m from the stack. TCE concentration in soil decreased as the distance from the stack lengthened. TCE concentration in groundwater from a well of 10 m depth located at the factory was 15000 μg/l at the average. cis-1, 2-Dichloroethylene, a product from TCE by biodegradation, were also detected in groundwater at 1700 μg/l at the average. TCE exhausted to the air distributed in air and soil, but this TCE did not cause groundwater contamination at the level of more than several mg/l.