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Guidance: Issuing UAOs for RD/RA Evaluation and Guidance

Memorandum presents results of evalauation of the selection process EPA uses in issuing unilateral administrative orders (UAOs) to potentially responsible parties (PRPs) for remedial design/remedial action (RD/RA) under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA, commonly referred to as Superfund).  OSWER Directive No. 9833.2c. Issued 6/20/1991.

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