Effective December 30, 2013, the EPA acted to amend the standards and practices for conducting all appropriate inquiries (“AAI”) to embrace an update to ASTM International standards, and to expressly bring vapor issues to the forefront during due diligence investigations. The changes are not mandatory at this time but are “strongly encouraged” by the EPA. Specifically, the final rule amends the AAI rules at 40 CFR Part 312 to make clear that those engaged in such inquiries may use the procedures included in the ASTM International Standard E1527–13 Standard Practice for Environmental Site Assessments: Phase 1 Environmental Site Assessment Process to comply with the AAI rule.

Parties affected include public and private parties seeking bona fide prospective purchaser status, contiguous property owners, or innocent landowners. Accordingly, anyone acquiring potentially contaminated property and intending to claim protection from CERCLA liability should review the amended rule.

The rule also may affect parties performing either a site characterization or assessment on a property with a brownfields grant conferred under relevant provisions of CERCLA. This includes state, local and tribal governments that have received brownfields site assessment grants.

The ASTM standard newly recognized by the EPA enhances the previous standard regarding the delineation of historical releases or recognized environmental conditions; it also revises the standard practice to clarify that all appropriate inquiries and phase 1 environmental site assessments must include within the scope of the investigation an assessment of both the real or potential occurrence of vapor migration and vapor releases affecting the subject property.

Additional revisions include the following:

• Updates the definition of “Recognized Environmental Condition” (“REC”) 
• Updates the definition of “Historical Recognized Environmental Condition” (“HREC”) 
• Adds a definition for “Controlled Recognized Environmental Condition” (“CREC”) 
• Clarifies the definition of “de minimis condition” 
• Modifies the definition of “migrate/migration” to include vapor migrations 
• Recognizes that the definition of “release” conveys the same meaning as the definition of “release” under CERCLA 
• Adds guidance related to the regulatory agency file and records review needed to provide a standardized framework for verifying agency information obtained from key databases

EPA believes that the non-mandatory (but otherwise salutary) clarifications will provide prospective purchasers with enhanced information regarding the nature of historical releases at a target property – including the potential for vapor impacts – and therefore will provide prospective purchasers with a better basis for making informed decisions regarding potential future uses of the property.

Parties contemplating the purchase of contaminated sites should confer with their environmental professionals about potentially integrating the alternative standards into their due diligence. The EPA anticipates that parties relying upon an AAI investigation will “generally adjust” and move to the updated standard quickly.