Comparative Chemical and Physical Risk Assessment for Two Remedial Alternatives

Comparative risk assessment at former manufacturing site

At a former Superfund site with dioxin-contaminated soils in northern New Jersey, the public was concerned that the completed onsite containment remedy would be less effective than an excavation/offsite incineration remedy. The U.S. EPA was considering whether to change the existing remedy during the scheduled two-year review of the site.

Cardno ChemRisk performed a screening-level comparative risk assessment for two remedial alternatives for a former pesticide manufacturing Superfund site in northern New Jersey with dioxin-contaminated soils. The comparative risk assessment presented the physical and chemical risks associated with two remedial alternatives: onsite containment and excavation followed by offsite incineration in Kansas.

The assessment showed that the chemical risks due to the excavation/offsite incineration remedy were 10 times greater than those associated with onsite containment; the risk of at least one job-related fatality during remedy implementation was more than 10 times higher for the excavation/offsite incineration remedy versus onsite containment; and the risk of an accident or fatality while contaminated materials were being transported for excavation/offsite incineration remedy was 1,000 times higher than the onsite containment remedy. The U.S. EPA Region 2 subsequently gave full approval to the onsite containment remedy. The risk assessment of physical hazards was published in peer-reviewed scientific literature (Scott et al., 2001).

Comparative risk assessment at former manufacturing site