In 2017, EPA finalized a rule that updated its Hazard Ranking System (HRS), used to determine when to add contaminated sites to the National Priorities List (NPL), to allow ranking of sites based on subsurface intrusion, including both vapor and water seepage from underground contamination.  EPA has now added the first two sites to the NPL based on vapor intrusion alone—on September 11, EPA finalized listing of the Rockwell International Wheel & Trim site in Grenada, Mississippi, and the Delfasco Forge site in Grand Prairie, Texas on the NPL.  The Rockwell site was listed because of vapors of trichloroethylene (TCE)… Read more