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Superfund Unilateral Orders

EPA can order parties to perform cleanup work under the following circumstances:

  • If potentially responsible parties (PRPs) do not agree to perform the cleanup work through a judicial consent decree or an administrative order on consent (AOC), or
  • refuse to perform work they previously agreed to perform under a settlement agreement

These orders, known as unilateral administrative orders (UAOs), require parties to undertake a response action, either a short or long-term cleanup.

EPA can issue a UAO when it finds there may be an imminent and substantial endangerment to the public health or the environment.

If PRPs do not comply with a UAO, courts may:

  • assess penalties,
  • require the PRP to pay up to three times what it cost EPA to do the cleanup (treble damages),
  • issue a judicial order requiring cleanup.

EPA policy documents, along with model language documents for UAOs, are available from the Superfund cleanup policy and guidance database.

Learn More: Superfund Cost Recovery