An official website of the United States government.

This is not the current EPA website. To navigate to the current EPA website, please go to This website is historical material reflecting the EPA website as it existed on January 19, 2021. This website is no longer updated and links to external websites and some internal pages may not work. More information »


Superfund "Notice of Liability" Letters

EPA uses two types of letters to communicate with potentially responsible parties (PRPs) regarding

  • their identification as a PRP,
  • their potential liability at a Superfund site,
  • information regarding the site and other PRPs, and
  • negotiations for the cleanup of the site.

General Notice Letters

General notice letters inform recipients that they are:

  • identified as PRPs at Superfund sites,
  • that they may be liable for cleanup costs at the site, and
  • explains the process for negotiating the cleanup with EPA.

The letter also includes information on Superfund, the site, and may include a request for additional information.

Special Notice Letters

EPA sends out a special notice letter when it is ready to negotiate with PRPs to clean up a site. A special notice letter gives PRPs information on why EPA thinks they are liable and EPA's plans for the cleanup of the site.

The letter also invites parties to participate in negotiations with EPA to conduct future cleanup work and pay EPA for any site-related costs already incurred.

The special notice letter triggers the start of a "negotiation moratorium," which means that EPA agrees, for a certain period of time, not to unilaterally order the PRP to conduct the cleanup. This moratorium period is intended to encourage the PRPs to negotiate a settlement agreement promptly.

EPA's general policy is to always issue special notice letters. EPA may decide not to issue a special notice letter when:

  • past experience with the PRPs indicates a settlement is unlikely,
  • no PRPs have been identified, or
  • PRPs lack the resources to do what is needed.

Additional information on notice letters is available in EPA's Interim Guidance on Notice Letters, Negotiations, and Information Exchange  (10/19/1987) and from the notice/demand letters subject category within the Superfund Enforcement policy and guidance database.

Learn More:

Top of Page