摘要：A ground water pollution by comparatively high leveled contamination with 1, 1, 1-trichloroethane and trichloroethylene in Sendai city was investigated. In order to draw the contour of concentration of volatile halogenated hydrocarbons, we investigated by multivariate analysis of 8 chemical elements in well water whether each well water was originated from the same ground water layer. 1, 1, 1-trichloroethane was detected in the water of wells wide-spreaded around a dry cleaning shop. And the pollution extended downstream of ground water in the direction of ground water flow. Area over the standard provided by the Ministry of Public Welfare, 300 ppb, was estimated spreading about 200 m from east to west and 50-70 m from north to south. Concentration of the most polluted well was 2150 ppb and declined as time passed. Amount of 1, 1, 1-trichloroethane showed a logarithmic decrease after soil permeation. Contour of contamination of trichloroethylene reached about 700 m from east to west and 300 m from north to south. Contamination level of a well in the neighborhood of some metal-working factories in June 1984 became 30 times higher (330 ppb) than that found four month before. As some organic solvents were used in these factories, it was suspected that some of them are sources of this contamination.
关键词：ground water pollution;multivariate analysis;volatile halogenated hydrocarbons;1, 1, 1-trichloroethane;trichloroethylene
