Abstract: Methodology and procedures for studying soil remediation goals are introduced,based on human health risk assessment.Properties of PAH-contaminated soil and exposure scenario in the landfill site are analyzed and simulated.Results show that the maximum exposure intake(MEIs) benzo(a)pyrene by oral ingestion and dermal contact is 1.89×10-6 and 0.93×10-6 mg·kg-1·d-1,respectively.The maximum carcinogenic risk(MCRs) of the two exposure pathways is at 1.38×10-5 and 6.79×10-6,separately,both of which exceed the acceptable carcinogenic risk level of 10-6.This level is the benchmark regulated for assessing the human health impact from the individual carcinogenic contaminant in China.The MEI of benzo(a)pyrene by inhalation is 7.79×10-10 mg·m-3 and its MCR is 6.86×10-10.Taking into account site-specific geo-condition and parameters,the remediation targets(w,mg·kg-1)of 5 PAHs,including benzo(a)pyrene,dibenzo(a,h)anthracene,benzo(a)anthracene,benzo(b)fluoranthene and benzo(k)fluoranthene,for reuse of the mid-layer of overlying soil in landfill sites are set at 0.994,0.995,9.95,9.95 and 99.5,respectively.

Key words: PAH, soil remediation, exposure scenario simulation, human health, risk assessment, safe disposal, reuse