摘要
为溯源某有机污染场地对天然泉的持续释放,研究分丰、枯水期以及雨前、雨中和雨后过程采集天然泉水样,同时采集污染场地周边土样,以有机污染物六六六、滴滴涕、荧蒽、芘、苯和三氯甲烷为主要溯源对象,利用气相色谱和气质联机仪测定。土壤有机污染物溯源结果发现天然泉上游2个化工企业内及周边土壤中HCHs、荧蒽和芘出现污染异常;天然泉水丰水期、枯水期HCHs浓度分别为12.1ng/L和72.7ng/L,枯水期泉水浓度高于丰水期6.0倍,推测与地下水上升引起的稀释作用有关;三氯甲烷浓度分别为4.34μg/L和1.50μg/L,丰水期泉水浓度高于枯水期2.9倍,苯仅在丰水期少量释放;荧蒽、芘仅在降雨过后释放,推测降雨量大有利于挥发性有机物入渗;污染场地周边包气带中有机污染物的垂直分布显示有机污染物的迁移呈逐渐减弱趋势,并与总有机碳、黏粒、阳离子交换量以及它们的物理化学性质密切相关。因此该研究溯源到2个企业存在污染场地,HCHs和三氯甲烷呈现持续释放状态,PAHs和苯为潜在释放状态,并呈现季节性变化。
To trace the source of organic pollution to a natural spring,water samples were collected respectively in rainy season and dry season,and were tapped before,in the middle and after the rainfall process;besides,soil samples around the suspicious contaminated ground were taken simultaneously. Organic pollutants such as HCHs,DDT,fluoranthene,pyrene,benzene and chloroform were analyzed utilizing GC and GC-MS. The tracing investigation indicated that soil samples around two chemical factories and at the places upstream of natural spring showed concentrations of HCHs and polycyclic aromatic hydrocarbons（PAHs）were abnormally high. Meanwhile,HCHs concentration of natural spring water in dry season was 6.0 times higher than that of rainy season,but chloroform concentration in rainy season was higher than that in dry season. As for VOCs including benzene,fluoranthene and pyrene,it was found rainfall in rainy season were conducive to the release of them to infiltrate into groundwater. The vertical distribution of organic pollutants in vadose zone around the contaminated site suggested that their migration behavior were in a pattern of gradually reducing tendency,and were closely related with the factors of TOC,cation exchange capacity and clay particulates as well as their physical and chemical properties. Conclusively,the investigation has traced the sources of organic contamination,i.e. two chemical factories;among the organic pollutants,HCHs and chloroform both maintained sustained releasing status,and PAHs and benzene formed a kind of potential releasing featuring seasonal changes.
出处
《环境科学与技术》
CAS
CSCD
北大核心
2015年第3期174-181,共8页
Environmental Science & Technology
基金
中国地质调查局地质调查项目资助:西南主要城市地下水污染调查评价(1212011121166)
关键词
污染场地
有机污染物
天然泉
持续释放
溯源
organic contaminated site
organic pollutants
spring
sustained releasing
tracing the source
