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Environmental Cleanup

Cleaning up and restoring to past conditions those areas contaminated by activities of our modern world is now a top priority not only for governments, but also for a variety of organizations responsible for contamination or hired to clean it up. Given the diversity of sources of hazardous waste, ranging from households, farms or small businesses to manufacturing plants, mining operations or the federal production of nuclear weapons, cleanup activities are now commanding attention throughout society. This information sheet is designed to give an overview of the cleanup process and associated cleanup terms.

Topics:

• Environmental Restoration
• The Cleanup Process
• The Superfund Cleanup Process (CERCLA)
• The RCRA Corrective Action Process

A full spectrum of activities to restore to safe conditions those sites contaminated by hazardous or radioactive wastes. Restoration includes:

Decommissioning:

The removing of a contaminated facility from operation, usually a facility used for nuclear-related work and potentially contaminated with radioactivity. This process may include decontamination and dismantling or converting to another use, or the entombment of the facility to prevent contamination of the surrounding environment.

Decontamination:

The removal of hazardous material (typically, radioactive) from facilities, soils or equipment, usually by washing, chemical action or mechanical cleaning. This returns such sites, facilities, or equipment to safe conditions for additional use, or possibly easier, less costly disposal.

Public Participation:

Efforts to inform and involve the public concerning activities at a contaminated site. This may include not only general announcements, public documents and a reading room making pertinent information available, but possibly public meetings with interaction to hear and respond to community concerns, consideration of community views and involvement of stakeholders in decision making through such methods as advisory groups. Informing and involving the public is required for many sites (according to the National Environmental Protection Act for federal activities having environmental impact, CERCLA for all Superfund sites and DOE regulations for all DOE activities).

Remediation:

Correcting or cleaning up sites contaminated with hazardous or radioactive wastes. Generally this term refers to the whole process (assessing the problem and then cleaning it up); however, as a regulatory term, the Environmental Protection Agency (EPA) uses remedial action to mean only those activities after a cleanup remedy is chosen (does not include assessing the problem). Within the Department of Energy (DOE), remediation refers to the whole process, including reconnaissance, site assessment, cleanup activities and finally, site compliance monitoring.

Stakeholders:

Anyone with a stake or interest in the waste management or cleanup activities of a contaminated site. This may include citizens affected by a contaminated site, other interested citizens or parties, organized groups, community or state officials, regulators, etc. Cleanup laws and regulations now require inclusion of interested stakeholders in the cleanup process.

While specific terms for steps in the process of cleaning up a contaminated site may vary among organizations or sites, this section lists some of the most common general terms. Terms used specifically for cleanups falling under Superfund or RCRA legislation are listed later.

Reconnaissance:

Preliminary evaluations to determine if there is a contamination problem and if necessary, plan for further assessment. This involves reviewing records, interviewing personnel, inspecting the site, taking and analyzing samples, and possibly preparing a plan for a complete assessment. (Reconnaissance activities are analagous to the Preliminary Assessment and Site Inspection steps of the Superfund process listed later.)

Site Assessment:

A thorough evaluation of contamination at a site and the alternatives for cleaning it up. Assessment concludes with the selection of the most effective cleanup remedy based upon the type and content of contamination, environmental characteristics, available technologies and compliance with all regulations. Assessment generally includes site characterization, risk assessment and an evalution of all cleanup alternatives. (Under the Superfund process, these activities are called the Remedial Investigation/Feasibility Study.)

Characterization:

The methodical scientific process used during site assessment to determine the type and extent of contamination. This involves analyzing soil, water, flora and fauna samples and evaluating the area's geologic characteristics to determine pathways of movement and potential risks to the environment and human health.

Risk Assessment:

Scientific effort to estimate the nature, probability and magnitude of risk to public health or the environment from the contaminated site. Includes an evaluation of the toxicology of the contaminants and the routes by which the contaminants may reach the soil, plants, animals, groundwater or people.

Cleanup Activities:

The remedy chosen to most effectively restore a particular contaminated site to safe conditions. Activities may include treatment, containment, removal and ultimately, disposal of contaminated materials.

Site Compliance Monitoring:

On-going activities to ensure that no further contamination problems arise, whether the site is closed or remains active.

The process was established by the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA), commonly known as Superfund. Those sites determined by the Environmental Protection Agency (EPA) to be among the nation's most serious are put on the National Priorities List and must follow this process regulated by EPA. Terms of the CERCLA process are described below.

Site Discovery:

When EPA finds or is made aware of a potentially hazardous site. Many hazardous waste problems are brought to EPA's attention by citizens, businesses or communities as well as state or federal officials.

Preliminary Assessment (PA):

The initial evaluation or screening of a site, usually a review of existing information without an actual site visit, to determine if further study is warranted.

Site Inspection (SI):

An on-site investigation, possibly including sampling, to collect more extensive information to determine if contamination is present at an identified site and the nature of the potential hazard. Information from this investigation must support a decision to remove the site from further study or proceed with the process and the possible ranking of the site. (Combined with the PA, the PA/SI is analogous to the general term "Reconnaissance")

Response Action:

A federally-authorized action to respond to environmental contamination at a Superfund site. There are two types: removal action taken over the short term to respond quickly to a more immediate danger without having to follow a lengthy process before taking action; and remedial action involving long-term activities to reach a permanent cleanup solution following all steps of the Superfund cleanup process outlined here.

Hazard Ranking System (HRS):

Method the EPA uses to assess the relative threat from a site containing hazardous substances. Sites that score above a certain number are proposed to be added to the National Priorities List (NPL). The system assigns the highest scores to sites that pose actual threats to nearby residents and sensitive environments.

National Priorities List (NPL):

The list of the nation's worst hazardous waste sites determined by EPA and targeted for long-term cleanup and evaluation as established by CERCLA or Superfund. Initially "proposed" to the list, a site's listing on the NPL is finalized after a public comment period to seek additional input. Sites are removed from the NPL if new information shows it does not warrant listing. Sites are deleted from the list when all cleanup actions have been completed (59 sites, as of 5/94). EPA currently lists 1286 sites on the NPL (54 of those are proposed rather than finalized) with 20 of those on the NPL list being DOE sites.

Remedial Investigation (RI):

A thorough evaluation of contamination at a site to determine the nature and extent of the problem and gather enough information to evaluate how to clean it up. This involves full characterization with sampling and monitoring as well as a risk assessment.

Feasibility Study (FS):

A formal evaluation of options for cleaning up a site. Based upon data gathered during the Remedial Investigation, this study defines objectives for the cleanup, identifies possible cleanup methods, and evaluates those methods in detail according to nine criteria concerning effectiveness, ability to implement, cost-effectiveness, concerns of stakeholders and compliance with all applicable regulations. As part of the overall Site Assessment, the Feasibility Study is often combined with the Remedial Investigation and the two are referred to as the Remedial Investigation/Feasibility Study or RI/FS (Analagous to the general term, Site Assessment).

Criteria for Selecting a Cleanup Plan:

Choosing a cleanup strategy for a Superfund site requires a comparative evaluation of the options analyzed in the Feasibility Study according to nine criteria prioritized into three groups. (1) The threshold criteria, which must be met for an alternative to be considered, are: overall protection of human health and the environment; and compliance with Applicable or Relevant and Appropriate Requirements (ARARs). (2) The five primary balancing criteria, which must be evaluated for the most effective balance, are long-term effectiveness and permanence; reduction of toxicity, mobility or volume through treatment; short-term effectiveness; implementability; and cost. (3) The two modifying criteria to be considered are state and community acceptance of the alternatives.

Proposed Plan:

A public document presenting the Superfund site cleanup strategy determined at this point to best meet the needs at the site (according to the established criteria given above). This plan summarizes the detailed analysis of alternatives in the Feasibility Study, identifies the preferred alternative, explains the rationale for the preference, and provides an opportunity for public comment on all alternatives under consideration.

Final Remedy Selection:

Selection of a cleanup plan based upon any new community concerns and information brought out after publication of the proposed plan as well as the rationale put forth in that proposal.

Record of Decision (ROD):

Public documentation of the final selection of a cleanup plan for a Superfund site. The ROD details the action to be taken, explains how the selected remedy will meet the remediation goals and responds to public comments or concerns.

Remedial Design:

The technical analysis and procedures developed after the selection of a remedy for a site resulting in a detailed set of plans and specifications to implement the cleanup.

Remedial Action (RA):

The actual cleanup of a contaminated site. These activities designed to prevent or minimize danger to public health or the environment from hazardous substances, may include storage, segregation, confinement, treatment, removal or disposal of hazardous or contaminated materials and monitoring to ensure the actions are effective. (This differs from the more immediate Removal Action; see Response Action above.)

Operation and Maintenance (O&M):

Activities at a site after remediation goals have been met and the response action is complete to ensure a cleanup or containment system's continued effectiveness. This may include fence maintenance or routine monitoring and at this point becomes, state rather than federal responsibility.

Deleted:

Removal of a cleaned-up site from the National Priorities List. A site is proposed for deletion only after EPA and the applicable state agree that all cleanup activities are completed and no further response is needed to protect human health or the environment. Public comment must be requested and considered before the site is finally deleted.

Activities to cleanup or prevent the release of hazardous materials into the environment from hazardous waste generators or facilities that treat, store and dispose of waste follow this process regulated by the EPA under the authority of the Resource, Conservation and Recovery Act (RCRA). Terms of the RCRA Corrective Action process are described below.

RCRA Facility Assessment (RFA):

Analogous to the Superfund Preliminary Assessment/Site Inspection, this includes a desk top review of available information, a visual site inspection and possibly a sampling visit to confirm or disprove suspected releases of hazardous substances and determine whether corrective action or more investigation is needed.

Interim Measure:

Actions that may be taken at any point in the process to address immediate threats to human health or the environment or prevent further environmental degradation while awaiting the outcome of additional studies to determine the most effective long-term response.

RCRA Facility Investigation (RFI):

Undertaken after a potentially significant release has been identified in the RFA, this investigation is designed to thoroughly assess the nature and extent of contamination in order to evaluate what, if any, action is necessary. (Analogous to the Superfund Remedial Investigation.)

Corrective Measures Study (CMS):

An evaluation to identify and evaluate potential remedies for the identified problem. A facility may be required to undertake a CMS whenever concentrations of hazardous substances in an aquifer, surface water, soils or air are found to exceed specified levels. This may be before as well as after the RFI is completed and may result in simultaneous work on the RFI and the CMS. While the CMS is equivalent to the Superfund Feasibility Study, RCRA facilities are more likely to be able, when appropriate and authorized, to streamline this analysis and evaluate fewer alternatives than Superfund sites. Facilities may be required to submit a plan before conducting this study, progress reports during the study as well as the mandatory final report.

Remedy Selection:

Selection of a remedy is not final until public comments have been considered through the permit modification process; however, tentative selection of a remedy is based upon two sets of factors, specifically general standards and decision factors. The four general standards that all alternatives must meet are: be protective of health and environment; attain appropriate cleanup standards; prevent to the extent practicable further harmful releases; and comply with waste management standards. The five decision factors used to select among alternatives meeting the initial four standards: long-term reliability and effectiveness; reduction of toxicity, mobility or volume of wastes; short-term effectiveness; implementability; and cost, with relative weights of these factors varying from site to site depending upon specific site characteristics. Along with selection of a remedy, standards are set that must be achieved for the cleanup to be considered completed.

Permit Modifications:

RCRA-permitted treatment, storage and disposal facilities (or those facilities requesting a permit) that require corrective action may have to modify their permit to include completion of the corrective action. This process allows for public review and comment of the planned remedy, the chosen cleanup standards, schedule of compliance and reporting requirements. A draft permit modification is issued for public notice and comment before the final permit modification is approved by EPA.

Statement of Basis:

A public document describing the basis for EPA's tentative remedy selection or approval and an explanation for the cleanup standards chosen. Analogous to the Superfund Record of Decision, this is included in the draft permit modification and made available to the public with time given for comment, response and reconsideration before remedy selection is final.

RCRA Remedial Design:

Detailed construction plans and specifications for implementing the remedy. Prepared after EPA has approved the selected remedy, this includes all implementation, long-term operation, monitoring and maintenance plans, a project schedule and a program to assure quality assurance.

Corrective Measure Implementation:

The actual corrective action activities to prevent or minimize danger to public health or the environment from hazardous waste treatment, storage or disposal. The EPA oversees these activities through progress reports and possibly, on-site inspections.

Completion of Remedy:

Correction action is considered complete after a facility certifies to the EPA with agreement from an appropriate independent professional that it has: met all cleanup standards as established in the remedy selection, including a certain amount of post-implementation monitoring; completed source control as specified to prevent further contamination; and complied with procedures for removal or decontamination of contaminated materials and facilities.

Closure Plan:

Not usually part of a corrective action process, this is documentation prepared to guide the deactivation, stabilization and surveillance of a waste management unit or facility that is closing.

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Disclaimer

Last Modified: 1 January 2002 by dave eckels
Projects: etd/library/infopages/cleanup.html