典型焦化场地地下水优控污染物筛选

Screening of groundwater priority pollutants in typical coking sites

基于潜在危害指数的综合评分法是筛选地下水优控污染物的常用方法。对于污染场地而言,现有的综合评分法指标体系中存在个别指标筛选作用失效、未考虑环境介质中污染物浓度超标等问题。本文从焦化场地污染特征出发,改进了综合评分法的指标体系,对山西省7个焦化场地地下水污染物进行了筛选。研究结果表明:地下水优控污染物包括萘、苯、甲苯、1,2二氯乙烷、苯酚、铜、镍、铅、镉、汞等10种。改进之后的筛选方法能够识别出排放量大、污染程度高、亟需进行管控的污染物。由于焦化企业废水、废气、废渣的成分复杂,目前开展的地下水调查所监测的污染物种类有限,导致筛选结果有所遗漏,建议开展地下水补充调查,进行地下水水质全分析,完善优控污染物清单,为焦化场地地下水污染防控提供更全面、更准确的数据支撑和决策依据。

The comprehensive scoring method based on potential hazard index is a commonly used method for screening priority pollutants.For contaminated sites,there are some problems in the existing comprehensive scoring index system,such as the failure of screening individual indicators and the failure to consider the concentration of pollutants in environmental media exceeding the standard.Based on the pollution characteristics of coking sites,this paper improves the index system of comprehensive scoring method and screens groundwater pollutants in 7 coking sites in Shanxi Province.The results show that 10 kinds of groundwater pollutants including naphthalene,benzene,toluene,1,2 dichloroethane,phenol,copper,nickel,lead,cadmium,mercury.The improved screening method can identify pollutants with large emissions,high pollution level and urgent need for control.Due to the complex composition of wastewater,waste gas and waste residue in coking plant,the types of pollutants monitored in groundwater survey are limited,which may lead to omissions in the results of screening.It is suggested that supplementary groundwater survey be carried out,groundwater quality analysis be carried out,and list of pollutants under excellent control be perfected to provide more comprehensive and accurate data support and decision-making basis for groundwater pollution control in coking sites.