Document is intended to supplement the 9/22/1987 federal Superfund liens guidance which provided criteria for the decision to file liens under section 107(1) of the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA, commonly referred to as Superfund). Issued 7/29/93.

Transmittal package includes two model document notice letters: (1) pre-perfection notice, and (2) post-perfection notice.

Principles in this memorandum were re-emphasized in the 5/28/2002 guidance on using federal Superfund liens to secure response costs.

PDF file of 7/29/1993 document:

• Supplemental Guidance on Federal Superfund Liens (PDF)(15 pp, 826 K, 7/29/1993)