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Guidance: CERCLA Section 106(a) UAOs for RD/RAs

This memorandum sets forth general principles governing the Agency's unilateral administrative order (AUO) authority for remedial designs and remedial actions (RD/RA) under section 106(a) of the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA, commonly referred to as Superfund), as amended by the Superfund Amendments and Reauthorization Act of 1986 (SARA). OSWER Directive Number 9833.0-1a. Issued 3/7/1990.

When initially posted on the Agency's website, this file included a quick reference fact sheet titled "Summary of Guidance on CERCLA Section 106(a) UAOs for RD/RA," issued May 1991, publication number 9833.0-1aFS.

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