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Guidance: PRP Participation in RI/FS

Memorandum transmitting a revised interim guidance on potentially responsible party (PRP) participation in remedial investigations and feasibility studies (RI/FS) under the Comprehensive Environmental Response, Compensation, and Liability (CERCLA, commonly referred to as Superfund) that was originally issued in May 1988. OSWER Directive No. 9835.2A. Issued 2/7/1989 (signed 1/26/1989).

The 5/1988 version of the guidance needed updating to correct inconsistencies and additional corrections identified after the Agency issued an RI/FS guidance in October 1988.

The 1989 revisions to the PRP participation in RI/FS interim guidance do not affect the policy aspects of the guidance.

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