(94c) Assessment of Vapor Intrusion into Structures on Property Involved in Real Estate Transactions: The New Astm Standard Practice

ASTM recently introduced a new Standard Practice for conducting vapor intrusion assessment at properties involved in real estate transactions. The tiered process is meant to supplement the existing Phase I environmental site assessment standard practice (ASTM - E1527), which does not explicitly include an assessment for vapor intrusion potential. The first two tiers are screening tiers designed to assess the potential for a a vapor intrusion condition to exist. if it is reasonably probable that a vapor intrusion condition may exist and it is desired to confirm the situation, the third tier in the standard presents a "toolbox" of actions that can accomplish this. The fourth tier addresses mitigation alternatives. It is not necessary to progress sequentially through each tier in the process. For example, from Tier 1 one can move directly to any of the other tiers or even directly to mitigation in Tier 4.