Screening of groundwater priority pollutants in typical coking sites

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.