美国污染场地清理的风险评估简介及政策制定

Brief Introduction of Pollution Sites Remediation and Risk Assessment and Its Policy Making in United States

本文主要介绍美国加州污染场地清理的风险评估的概念,方法,计算和风险管理.从而引进挥发性污染物室内入侵风险评估方法来制定污染场地清理标准.讨论如何运用数学模型计算土壤清理浓度和挥发性污染物室内入侵风险评估.在风险评估基础上,加州环保署水质管理局颁布了地下储油罐低风险结案政策.政策中的污染场地清理定量标准是由人体健康风险评估方法计算得出.最后,用一个具体的美国加州洛杉矶案例介绍风险评估方法是怎样运用在污染场地清理修复中,以回答污染场地修复的关键问题"多干净算干净".

Site remediation has become an imperative part of environmental protection in China due to recent economic development,urban spreading,new industries replacing old ones,relocation of old industrial sites,and increased environmental conscience.This paper mainly introduced the concept,method,calculation,risk assessment and management for polluted sites remediation based on experience from California,USA.Further,the paper presented the concept of vapor intrusion and how to use vapor intrusion methodology to determine site remediation standard.Mathematical modeling approaches were also discussed in terms of how to determine the residual pollutant concentrations in soil and how to calculate indoor vapor concentrations.Based on risk assessment,California Environmental Protection Agency,Water Resources Control Board issued a ‘Low Threat Underground Storage Tank Case Closure Policy＇for impacted underground storage tank sites.The numerical criteria in the Policy were based on calculations of human health risk assessment.Finally,a real case study in California,USA,was presented to demonstrate how the risk assessment calculations were applied in polluted site remediation,which helps to answer the question of ‘how clean is clean＇.