Only NPL sites are eligible for federally funded cleanup. The EPA refers non-NPL sites to the states for handling. Superfund requires responsible parties either to clean up the site themselves under EPA supervision or to reimburse the EPA for a government-led cleanup. If the EPA cannot locate any financially viable PRPs, the EPA may fund the entire cleanup. PRPs have taken the lead in more site cleanups than has the EPA in recent years.
Liability is strict, retroactive, and joint and several.
Strict liability means that the government need not show that the responsible party acted with intent or negligence. A party may be liable even if it has always complied with every law, rule, and regulation on waste disposal. Retroactive liability means that liability applies to actions that took place before enactment of Superfund. Joint and several liability means that a responsible party may have to pay the entire judgment against all liable parties, if the other parties are not financially viable. That is, physical construction is complete for all remedial and removal work required at the entire site.