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The drive toward a faster, fairer, more efficient Superfund

This page contains definitions to terms commonly used in the Superfund Reforms program. Scroll down or use the links below to navigate to individual sections.

NOTE: For additional definitions, see EPA's Terms of Environment page.

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administrative order on consent: A legal agreement signed by EPA and an individual, business, or other entity through which the violator agrees to pay for correction of violations, take the required corrective or cleanup actions, or refrain from an activity. It describes the actions to be taken, may be subject to a comment period, applies to civil actions, and can be enforced in court. Unlike a consent decree, an administrative order on consent does not have to be approved by a judge.

administrative record: A file which is maintained and contains all information used by the lead agency to make its decision on the selection of a response action under CERCLA. This file is to be available for public review and a copy is to be established at or near the site, usually at one of the information repositories. Also, a duplicate file is held in a central location, such as a Regional or State office.

alternative dispute resolution (ADR): A technique in which a neutral party helps organize negotiations, facilitates deliberations, and/or provides negotiating parties with an impartial opinion.


brownfields: Abandoned, idled, or under-used industrial and commercial properties where expansion or redevelopment is complicated by real or perceived environmental contamination.


CERCLA: Comprehensive Environmental Response, Compensation, and Liability Act (commonly known as Superfund). This law, enacted by Congress on December 11, 1980, created the Superfund program. Specifically, CERCLA (1) established prohibitions and requirements concerning closed and abandoned hazardous waste sites, (2) provided for liability of persons responsible for releases of hazardous waste at these sites, and (3) established a trust fund to provide for cleanup when no responsible party could be identified. CERCLIS: Comprehensive Environmental Response, Compensation, and Liability Information System. CERCLIS is an automated inventory of site information for all potential or confirmed Superfund sites.

comfort/status letters: Letters that provide any releasable information EPA has about a site, what that information means, and the likelihood that EPA will take Federal Superfund action. Comfort/status letters are used when (1) they may facilitate cleanup and redevelopment of brownfields, (2) there is a realistic perception or probability of incurring Superfund liability, and (3) no other mechanism could adequately address a party's concerns.

Community Advisory Group (CAG): A committee, task force, or board comprised of citizens affected by a hazardous waste site. CAGs provide a public forum for community members to present and discuss their needs and concerns about the decision-making process at sites affecting them.

consent decree: A legal document, approved and issued by a judge, that formalizes an agreement reached between EPA and potentially responsible parties (PRPs) where PRPs will conduct all or part of a cleanup action at a Superfund site; cease or correct actions or processes that are polluting the environment; or otherwise comply with EPA-initiated regulatory enforcement actions to resolve site contamination. The consent decree describes actions that PRPs are required to perform and may be subject to a public comment period.

construction completion: The stage in cleanup when physical construction of all cleanup remedies is complete, all immediate threats have been addressed, and all long-term threats are under control. Though long-term cleanup actions may still be operating, the site is often ready for economic, social, or environmental reuse.


de micromis party: Party whose contribution is equal to or less than (1) 0.002% of total volume or 110 gallons (such as two 55-gallon drums) or 200 pounds of materials containing hazardous substances, whichever is greater, or (2) 0.2% of total volume, if the party sent only municipal solid waste. EPA will not pursue a de micromis party for recovery costs, and if a private party threatens a small party with litigation, EPA will settle with that de micromis party for $0.

de minimis party: Party whose contribution of hazardous substances to a facility is minimal, both in terms of volume and toxicity (or other hazardous effects) relative to the other hazardous substances at the site. EPA will often offer small settlements to de minimis parties.


ecological risk assessment: The application of a formal framework, analytical process, or model to estimate the effects of human actions(s) on a natural resource and to interpret the significance of those effects in light of the uncertainties identified in each component of the assessment process. Such analysis includes initial hazard identification, exposure and dose-response assessments, and risk characterization.

enforcement: EPA, State, or local legal actions to obtain compliance with environmental laws, rules, regulations, or agreements and/or obtain penalties or criminal sanctions for violations. Under CERCLA, EPA will seek to require potentially responsible parties to clean up a Superfund site or pay for the cleanup.


Feasibility Study (See RI/FS)

future liability: Potentially responsible parties' obligations to pay for additional response activities beyond those specified in the Record of Decision or Consent Decree.


Hazard Ranking System (HRS): The principal screening tool used by EPA to evaluate risks to public health and the environment associated with abandoned or uncontrolled hazardous waste sites. The HRS calculates a score based on the potential of hazardous substances spreading from the site through the air, surface water, or ground water, and on other factors such as density and proximity of human population. This score is the primary factor in deciding if the site should be on the National Priorities List and, if so, what ranking it should have compared to other sites on the list.

health assessment: An evaluation of available data on existing or potential risks to human health posed by a Superfund site. The Agency for Toxic Substances and Disease Registry (ATSDR) exit epa of the Department of Health and Human Services (DHHS) exit epa is required to perform such an assessment at every site on the National Priorities List.


information repository: A file containing current information, technical reports, and reference documents regarding a Superfund site. The information repository is usually located in a public building that is convenient for local residents, such as a public school, city hall, or library.

innovative technologies: New or inventive methods to treat hazardous waste effectively, and reduce risks to human health and the environment.


joint and several liability: A concept which dictates that parties who contribute to a site's pollution are each liable as if they alone polluted that site. Under this concept any one party may be held liable for all cleanup costs. In such a case, this one party may be responsible for identifying others to share the liability.


municipal solid waste (MSW): Common garbage or trash generated by industries, businesses, institutions, and homes.


National Priorities List (NPL): EPA's list of the most serious uncontrolled or abandoned hazardous waste sites identified for possible long-term remedial action under the Superfund program. The NPL, which EPA is required to update at least once a year, is based primarily on the score a site receives from EPA's Hazard Ranking System. A site must be on the NPL to receive money from the Superfund Trust Fund for remedial action.

National Response Team (NRT): Representatives of 13 Federal agencies that coordinate Federal responses to nationally significant incidents of pollution (e.g., an oil spill, a major chemical release, or a Superfund response action) and provide advice and technical assistance to the responding agency (or agencies) before and during a response action.

No Further Remedial Action Planned (NFRAP): Decision made by EPA following a preliminary assessment that a site does not pose a significant risk and requires no further activity under CERCLA.

NPL-caliber sites: Sites with the potential for NPL listing that are not currently on the NPL.


off-site facility: A hazardous waste treatment, storage, or disposal area located away from the generating site.

Ombudsman: An appointee within each of EPA's ten Regions who serves as a direct point of contact for the public on Superfund issues. The ten Superfund Regional Ombudsmen (1) serve as facilitators to help resolve stakeholder concerns, (2) actively promote the concepts of alternative dispute resolution and facilitation to all Superfund stakeholders, and (3) provide Superfund stakeholders ready access to information so they may fully participate in the entire Superfund process.

on-site facility: A hazardous waste treatment, storage, or disposal area located on the generating site.

operable unit (OU): Term for each of a number of separate activities undertaken as part of a Superfund site cleanup. A typical operable unit would be removal of drums and tanks from the surface of a site.

orphan share: The financial responsibility assigned to a potentially responsible party (PRP) who is insolvent or defunct and unaffiliated with other viable liable PRPs. Orphan share compensation provides a major incentive for responsible parties to perform cleanups and settle claims quickly without litigation, and reduces transaction costs by wholly or partly resolving the question of who should bear the burden of orphan shares.


pilots: Approved tests of a new initiative or idea to identify potential problems prior to full-scale implementation. Many of the Superfund Reforms have used pilot sites to test new technologies and processes.

potentially responsible party (PRP): An individual or company (e.g., an owner, operator, transporter, or generator of hazardous waste) that is potentially responsible for the contamination problems at a Superfund site. Whenever possible, EPA requires PRPs to clean up hazardous waste sites they have contaminated.

Preliminary Assessment (PA): The process of collecting and reviewing available information about a known or suspected waste site or release.

Proposed Plan: A site cleanup plan that is available for public comment.

prospective purchaser agreement (PPA): A legal agreement that protects the prospective buyer of a hazardous waste site from the liability associated with pre-existing contamination at the site. In return for liability protection, the buyer must advance environmental and/or community benefits (i.e., performing cleanup activities, reimbursing EPA for a portion of their cleanup costs, creating jobs, rehabilitating the property, participating in community revitalization). PPAs often enable redevelopment plans to be integrated into the cleanup activities at the site and ensure the long-term maintenance and operation of the cleanup.


Record of Decision (ROD): The primary legal document at a site, which sets forth EPA's selected remedy as well as the factors that led to its selection.

Remedial Design: A phase of remedial action that follows the remedial investigation/feasibility study and includes development of engineering drawings and specifications for site cleanup.

Remedial Investigation and Feasibility Study (RI/FS): Stage of cleanup that involves a remedial investigation and a feasibility study. The remedial investigation is an in-depth study to (1) determine the nature and extent of contamination at a Superfund site, (2) establish site cleanup criteria, (3) identify preliminary alternatives for remedial action, and (4) support technical and cost analyses of alternatives. The feasibility study is an analysis of the practicability of a proposal (e.g., a description and analysis of potential cleanup alternatives), which usually recommends selection of a cost-effective alternative. It usually starts as soon as the remedial investigation is underway. Together they are called an "RI/FS."

Remedial Project Manager (RPM): The EPA or State official responsible for overseeing on-site remedial action.

Remedial Response: Long-term action that stops or substantially reduces a release or threat of a release of hazardous substances that is serious but not an immediate threat to public health.

remediation: Cleanup or other methods used to remove or contain a toxic spill or hazardous materials from a Superfund site.

Removal Action: Short-term immediate actions that address releases of hazardous substances that require expedited responses.

Response Action: A CERCLA-authorized action involving either a short-term removal action or a long-term removal response. This may include but is not limited to removing hazardous materials, containing or treating the waste on-site, and identifying and removing the sources of ground water contamination and halting further migration of contaminants.

risk assessment: Qualitative and quantitative evaluation of the risk posed to human health and/or the environment by the actual or potential presence and/or use of specific pollutants.


Science Advisory Board (SAB): A group established by Congress to provide independent scientific and engineering advice to the EPA Administrator on the technical basis for EPA regulations. Expressed in terms of the current parlance of the risk assessment/risk management paradigm of decision making, the SAB deals with risk assessment issues (hazard identification, dose-response assessment, exposure assessment and risk characterization) and only that portion of risk management that deals strictly with the technical issues associated with various control options.

site assessment: A means of evaluating hazardous waste sites through preliminary assessments and site inspections to develop a Hazard Ranking System score.

Site Inspection (SI): The collection of information from a Superfund site to determine the extent and severity of hazards posed by the site. This phase follows and is more extensive than a preliminary assessment. The purpose is to gather information necessary to score the site using the Hazard Ranking System, and to determine if the site presents an immediate threat requiring prompt removal.

smelter: A facility that melts or fuses ore, often with an accompanying chemical change, to separate its metal content. Emissions may cause pollution. The process involved is called "smelting."

stakeholder: Any organization, governmental entity, or individual that has a stake in or may be impacted by the Superfund program.

strict, joint and several liability: The liability scheme imposed by CERCLA (see strict liability and joint and several liability).

strict liability The assessment of liability for damages without requiring proof of negligence.

Superfund: 1.  The program operated under the legislative authority of CERCLA and SARA that funds and carries out EPA solid waste emergency and long-term removal and remedial activities. These activities include establishing the National Priorities List, investigating sites for inclusion on the list, determining their priority, and conducting and/or supervising cleanup and other remedial actions. 2.  A fund set up under CERCLA to help pay for cleanup of hazardous waste sites and to take legal action to force those responsible for the sites to clean them up. The Superfund consists of funds from taxes imposed upon the petroleum and chemical industries, an environmental tax on corporations, and from general tax revenues (also known as Trust Fund, and Hazardous Waste Superfund).

Superfund Accelerated Cleanup Model (SACM): An approach to cleanup that encouraged innovative ways to streamline the cleanup process. The idea was developed in 1992 by OSRTI to address public and congressional criticism that cleanups were too slow. With over a decade of experience, the program recognized the benefits to be gained from combining certain pipeline activities, particularly where previous experience could eliminate years of study and analysis. Under SACM, for example, an emergency response might be expanded to eliminate the need for later long term action at a site. Site evaluation sampling could be augmented to include tests that could assist in selecting a remedy further in the process. Certain remedies could be presumed appropriate based on past experience, without unnecessarily duplicating past studies during the remedy selection phase. SACM removed the artificial distinction between removal, site evaluation, and long-term remediation. It eliminated divisional "ownership" of a site according to where it was on the cleanup pipeline. Data needs, resources, and study could potentially be consolidated at several stages, reducing the time and cost of cleanup.

Superfund Amendments and Reauthorization Act (SARA): Legislation that amended the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) on October 17, 1986. SARA reflected EPA's experience in administering the complex Superfund program during its first six years and made several important changes and additions to the program. SARA stressed the importance of permanent remedies and innovative treatment technologies; required Superfund actions to consider the standards and requirements found in other State and Federal environmental laws and regulations; provided new enforcement authorities and settlement tools; increased State involvement; increased the focus on human health problems; encouraged greater citizen participation; and increased the size of the Trust Fund to $8.5 billion.


Technical Assistance Grant (TAG): Grants provided to citizens' groups to obtain assistance in interpreting information related to cleanups at Superfund sites or those proposed for the National Priorities List. Grants are used by such groups to hire technical advisors to help them understand the site-related technical information for the duration of response activities.

Trust Fund: (See definition 2 for Superfund)


unilateral administrative orders (UAOs): A legal document issued by EPA directing a potentially responsible party to perform site cleanup. A UAO sets forth the liabilty of the party for the cleanup, describes actions to be taken, and subjects the recipient to penalties and damages for noncompliance. Unilateral orders may be enforced in court. A UAO is EPA's most potent enforcement tool and a powerful settlement incentive. EPA usually only issues them to parties that are the largest contributors of waste to a site, are financially viable, and against whom there is strong evidence of liability.


WASTELAN: The most current version of CERCLIS, the database that houses all Superfund site information. Also referred to as "CERCLIS 3."

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