Land developers and remediators in Pennsylvania and New Jersey may soon have an easier time addressing soils containing benzo[a]pyrene, one of the most ubiquitous urban contaminants, thanks to updated information that was just released by U.S. Environmental Protection Agency (EPA). The new information comes from EPA's Final Assessment of Benzo[a]pyrene, which was completed in January 2017 and is now part of EPA’s Integrated Risk Information System (IRIS). The assessment includes revised estimates of several important toxicological parameters that are used by EPA and state regulatory agencies to develop risk-based standards for the remediation of environmentally-impaired sites. While the Final Assessment concludes that benzo[a]pyrene is still a potent carcinogen, the revised parameters show that the chemical is not as toxicologically potent as was previously thought. Once the regulatory agencies incorporate this new information into their cleanup programs, it should result in less stringent cleanup standards for impacted sites regulated at the state and federal level.

Benzo[a]pyrene is a polynuclear aromatic hydrocarbon (PAH) and is found as the result of the combustion of organic matter such as wood, coal, oil, gasoline, diesel fuel, kerosene, and charcoal. For these reasons, it is ubiquitous in urban and industrialized areas and is frequently encountered during the cleanup and redevelopment of sites in Pennsylvania and New Jersey, especially where urban fill materials are encountered. Benzo[a]pyrene is often the highest-risk contaminant at sites impacted by PAHs and historic fill materials such as ash, and drives the remediation of soil that would otherwise be accepted as "clean" for all other regulated substances.

The revised toxicity criteria form the basis for the New Jersey Soil Remediation Standards and the Pennsylvania Statewide Health Standards, which define the acceptable default levels of benzo[a]pyrene that can be present in soil. Using the equations prescribed by these programs, we have calculated the new, less-stringent standards that should take effect once Pennsylvania and New Jersey (which use different equations with different acceptable risk levels) revise their regulations to include the new EPA toxicity criteria:

NJ Soil Remediation Standard

PA Statewide Health Standard

Current Target

0.20 ppm

0.58 ppm

Future Target

0.45 ppm

4.24 ppm

Current and future cleanup targets for soil in a residential-use scenario.

Additionally, the revised toxicity values may have a positive impact on the availability of materials that qualify as “clean fill” for both export and import to redevelopment project sites. We anticipate a revision of Pennsylvania’s guidance document on the management of fill in 2017 and will provide updates on that document as they become available.