[1] The program is administered by the Environmental Protection Agency (EPA) and is designed to pay for investigating and cleaning up sites contaminated with hazardous substances.

The EPA seeks to identify parties responsible for hazardous substances released to the environment (polluters) and either compel them to clean up the sites, or it may undertake the cleanup on its own using the Superfund (a trust fund) and seek to recover those costs from the responsible parties through settlements or other legal means.

Approximately 70% of Superfund cleanup activities historically have been paid for by the potentially responsible parties (PRPs),[4] reflecting the polluter pays principle.

In November 2021, the Infrastructure Investment and Jobs Act reauthorized an excise tax on chemical manufacturers, for ten years starting in July 2022.

A score of 28.5 places a site on the National Priorities List, eligible for long-term, remedial action (i.e., cleanup) under the Superfund program.

Natural resource trustees determine and quantify injuries caused to natural resources through either releases of hazardous substances or cleanup actions[6] and then seek to restore ecosystem services to the public through conservation, restoration, and/or acquisition of equivalent habitat.

For the federal government, EPA,[8] US Fish and Wildlife Service,[9] or the National Oceanic and Atmospheric Administration[10] may act as natural resource trustees.

[13] CERCLA was enacted by Congress in 1980 in response to the threat of hazardous waste sites, typified by the Love Canal disaster in New York, and the Valley of the Drums in Kentucky.

[20][21] In 1994 President Bill Clinton issued Executive Order 12898, which called for federal agencies to make achieving environmental justice a requirement by addressing low income populations and minority populations that have experienced disproportionate adverse health and environmental effects as a result of their programs, policies, and activities.

[23] Some environmentalists and industry lobbyists saw the Clinton administration's environmental justice policy as an improvement, but the order did not receive bipartisan support.

The newly elected Republican Congress made numerous unsuccessful efforts to significantly weaken the program.

The Clinton administration then adopted some industry favored reforms as policy and blocked most major changes.

[24] Until the mid-1990s, most of the funding came from an excise tax on the petroleum and chemical industries, reflecting the polluter pays principle.

[25] Even though by 1995 the Superfund balance had decreased to about $4 billion, Congress chose not to reauthorize collection of the tax, and by 2003 the fund was empty.

[15]: 8 In November 2021, Congress reauthorized an excise tax on chemical manufacturers, under the Infrastructure Investment and Jobs Act.

The 2021 law also authorized $3.5 billion in emergency appropriations from the U.S. government general fund for hazardous site cleanups in the immediate future.

Four classes of PRPs may be liable for contamination at a Superfund site: The liability scheme of CERCLA changed commercial and industrial real estate, making sellers liable for contamination from past activities, meaning they can't pass liability onto unknowing buyers without any responsibility.

[4] The CERCLA also required the revision of the National Oil and Hazardous Substances Pollution Contingency Plan 9605(a)(NCP).

[39] CERCLA liability has generally been judicially established as joint and several among PRPs to the government for cleanup costs (i.e., each PRP is hypothetically responsible for all costs subject to contribution), but CERCLA liability is allocable among PRPs in contribution based on comparative fault.

[42] Information from the PA/SI is used by the EPA to develop a Hazard Ranking System (HRS) score to determine the CERCLA status of the site.

Once the Remedial Action has been completed, reviews are required every five years, whenever hazardous substances are left onsite above levels safe for unrestricted use.

In West Dallas, Texas, a mostly African American and Latino community, a lead smelter poisoned the surrounding neighborhood, elementary school, and day cares for more than five decades.

It was later revealed that EPA Deputy Administrator John Hernandez had deliberately stalled the cleanup of the lead-contaminated hot spots.

It was the largest radioactive spill in the US but received a long delay in government response and cleanup after being placed as a lower priority site.

Two sets of five-year cleanup plans have been put in place by US Congress, but contamination from the Church Rock incident has still not been completely cleaned up.