The U.S. Environmental Protection Agency (U.S. EPA) has proposed to add Vapor Intrusion (VI) to the Superfund program’s Hazard Ranking System (HRS). U.S. EPA uses the HRS to place sites on the National Priorities List (NPL) by evaluating four scoring pathways: ground water, surface water, air, and soil exposure.

The proposed regulation would expand the HRS to include assessment of public health risk from VI. U.S. EPA and state agencies, through a Cooperative Agreement, will identify the sites that pose the highest potential risk of VI contamination.

The proposed rule would allow U.S. EPA to consider sites where VI is the only exposure pathway. Similar to the way other components of the HRS are scored, the VI component risk score would be the product of the probability of exposure, quantity and duration of exposure, and number of receptors, divided by a weighting factor.

There are currently 1,073 CERCLA sites with potential VI risk and increasing public support for additional pathway evaluation. Geosyntec can help you navigate this pathway.

More Information

For more information about Geosyntec’s suite of vapor intrusion services and expertise, please view the Geosyntec Vapor Intrusion Statement of Qualifications PDF, and the Vapor Intrusion Practice Area page on our website.

For more information on the Addition of a Subsurface Intrusion Component to the Hazard Ranking System, visit https://www.federalregister.gov/articles/2016/02/29/2016-02749/addition-of-a-subsurface-intrusion-component-to-the-hazard-ranking-system