Abstract
Groundwater contamination with volatile chlorinated hydrocarbons (VCHs) was found in a metalware manufacturing district located in a central part of the Niigata Plain, Niigata, Japan. VCHs detected were trichloroethylene (TCE), tetrachloroethylene (PCE), 1, 1, 1-trichloroethane (MCF), cis-1, 2-dichloroethylene (cis-DCE) and 1, 1-dichloroethane (1, 1-DCA). VCHs concentrations in groundwater were ranged from <0.001 to 7.1 mg·l-1 for TCE, <0.0010.036 mg·l-1 for PCE, <0.0011.2 mg·l-1 for MCF. Concentrations of cis-DCE and 1, 1-DCA were <0.015.1 mg·l-1 and <0.010.61 mg·l-1, respectively ; cis-DCE and 1, 1-DCA might be produced biodegradedly in soil from TCE and MCF, respectively.
Groundwater in alluvial aquifers was mainly of the carbonate hardness type, while groundwater quality in diluvial aquifers depended on the location. Although the diluvial aquifers were not polluted by VCHs, some of the alluvial aquifers contaminated by VCHs.
Concentrations of TCE and cis-DCE were determined for a year in groundwater from a well of 10 m depth at a metalware factory using VCHs. The VCHs concentrations in groundwater were varied with the amount of groundwater pumped up from both the investigated well itself and well set around it as well as with the groundwater level.
