新疆焉耆盆地平原区地下水有机污染评价及污染成因

在新疆焉耆盆地平原区采集了42组地下水样品和10组地表水样品,首次将有机污染物纳入检测项目,检测有机污染物共计39项.对所有水样测试结果的统计显示:焉耆盆地平原区地下水中检出的有机污染物共有 3 种,分别是三氯甲烷、1,2-二氯乙烷和1,2-二氯苯,检出率分别为30.95%、2.38%和2.38%,检出的三项有机污染物含量均低于饮用水标准.通过多介质污染评价系统进行有机污染评价,各有机污染物检出点不会对环境造成明显危害.在焉耆盆地平原区不同的土地利用类型有机污染物检出率不同,检出率为牧草地 > 耕地 > 建设用地;检出的14组地下水有机污染物大部分分布在包气带岩性为亚黏土与亚砂土区域,其余分布在包气带岩性为砂砾石区域;地表水采样点中只有B03(开都河)检测出微量的三氯甲烷,地下水中检出的有机污染物不是来自于地表水的补给.

Assessment of organic pollution and study on pollution cause of groundwater in the plain area of Yanqi Basin,Xinjiang

In order to acquire the current status of groundwater quality in the plain area of Yanqi Basin, Xinjiang, 42 groundwater and 10 surface water samples were collected according to the relating requirements and standards. The detection of organic pollutants in the study area was the first time and totally come to 39 testing items. The samples were analyzed by qualified laboratories. The investigation results showed that there were three organic contaminants detected in groundwater. Among these compounds, detection rate of trichloromethane, 1, 2-dichloroethane and 1, 2-dichlorobenzene were 30.95%, 2.38% and 2.38%, respectively. Content of the three compounds did not exceed the drinking water standards. The organic pollution assessment results showed that in the plain area of Yanqi Basin the organic pollutants were not to do harm to environment. Detection rate of the groundwater organic pollutants of the different land use types were grassplot > cultivated land > construction land. Most of the 14 detection points of groundwater organic pollutants distributed the unsaturated zone of the loam and the sandy loam. The others distributed the unsaturated zone of the sandy gravel. Only the B03 (Kaidu River) were detected trace amounts of trichloromethane and the organic pollutants in groundwater were not from the surface water.