Vapor Intrusion standards over the past several years has become a hot-button issue among regulators and private parties as both sectors have attempted to come to terms with a lack of consensus on how best to assess and manage the risk posed by vapor intrusion. Caused by the migration of the impacts of soil or groundwater contamination into indoor environments, vapor intrusion has stymied parties dealing with the issue due to a lack of uniform assessment and mitigation standards as well as competing theories on migration patterns of subsurface vapors.
ASTM International (“ASTM”) took a major step in developing an industry standard with its release on March 3, 2008, of “Standard Practice for the Assessment of Vapor Intrusion into Structures on Property Involved in Real Estate Transactions,” (ASTM E 2600‐08). The standard, unlike the Standard Practice for Environmental Site Assessments: Phase I Environmental Site Assessment Process (ASTM E 1527‐05) (“Phase I”) is not specifically targeted towards satisfying legal obligations such as “all appropriate inquiry,” but offers varying levels of investigation and mitigation as a means of identifying, evaluating and addressing potential liability associated with vapor intrusion.
The liabilities faced by parties legally or financially connected to properties with vapor intrusion issues extend beyond remedial obligations to a host of statutory and common‐law liabilities, property value diminution claims and toxic exposure lawsuits from onsite personnel. Assessing and managing vapor intrusion as early as possible during development, or as soon as discovered at established sites, will help to limit liability. To this end, owners, developers and investors should give serious consideration to amending their customary due diligence activities to incorporate the new vapor intrusion standard.