EPA issued a proposed a rule on June 17, 2014, to withdraw recognition of ASTM E1527-05 as a standard for assessing brownfields and other sites for potential environmental liability (79 Fed. Reg. 34480). Under the proposed rule, which would amend the EPA’s all appropriate inquiries (AAI) rule under the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA), parties may now use the latest version of the voluntary standard—ASTM International's E1527-13—or follow EPA’s rule to meet AAI obligations. Conducting AAIs is one of the requirements for meeting liability defenses under CERCLA.

This action follows a December 2013 final rulemaking where EPA indicated that parties who purchase potentially contaminated properties may use either the new standard practice (ASTM E1527-13) or the older 2005 version of the standard practice (ASTM E15278-05) when conducting AAIs pursuant to CERCLA. EPA is accepting comments on the proposed rule through July 17, 2014.