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Introduction To Corrective Action




The conceptual site model (CSM) (2 pp, 62K, About PDF) Exit EPA disclaimer along with acceptable risk factors, cost, local policies, available technologies, and community input will all help dictate the appropriate cleanup method to apply to a leaking underground storage tank (LUST) site. Various remedial actions are reviewed for effectiveness, and a detailed corrective action plan (CAP) may be developed according to the requirements of the implementing agency. To ensure protection of public health, safety, and the environment, the site owner or his/her consultant may seek to discuss the proposed immediate actions directly with the implementing agency to avoid delays and misunderstandings. Possible corrective action options, such as excavation and removal, pump and treat, or soil-vapor extraction, undergo a thorough analysis to select a reasonable approach from both a technical and cost perspective. An evaluation report that summarizes the benefits and drawbacks of each alternative is usually prepared for review by government agencies. A pilot test may be necessary to determine the effectiveness of the selected remedy prior to full scale application. Once the review of alternatives is completed, a specific corrective action or set of actions is selected and implemented.

The selected remedial action is described in detail in the CAP and may include preparation of written specifications and detailed engineering drawings. The plan may require that the action be performed by qualified contractors and may outline strategies to help the tank owner or operator control costs. The plan may also include specific cleanup goals, a project schedule, and project milestones.

This section of the compendium offers an overview of the corrective action process as well as the operation, maintenance, and monitoring requirements that will likely be an integral part of the process.

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Corrective Action Plan

A corrective action plan (CAP) is a comprehensive plan that describes how a LUST will be cleaned up and justifies why this remedial method has been chosen. The CAP typically needs to be approved by the local implementing agency. Any confirmed release that requires a CAP also requires notifications to local municipal or county officials, notices in the local newspaper, and public hearings to provide a forum for parties who may be impacted by a specific response or corrective action. Additional measures may also be proposed to protect people from harm, such as supplying drinking water to nearby residences or venting indoor air spaces.

Risk-based decision-making (RBDM) is used in some states to determine the appropriate levels of action and oversight based upon the risk to human health and environmental receptors. One state example is offered in the links below. ASTM's E1739 Exit EPA disclaimer standard is an example of a framework for implementing a risk-based corrective action (RBCA) strategy. With this process, regulators can make sound, quick, consistent management decisions for a variety of sites using a three-tiered approach to data collection and site review.

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Corrective Action Guidance (17 pp, 291K, About PDF) Exit EPA disclaimer
Vermont Agency of Natural Resources Waste Management Division guidance on preparing a Corrective Action Plan (CAP).

Leaking Underground Storage Tank (LUST) Corrective Action Plan Guide (9 pp, 37K, About PDF) Exit EPA disclaimer
Utah Department of Environmental Quality guide on the process of preparing the CAP.

Life Cycle Cost Analysis (18 pp, 536K, About PDF) Exit EPA disclaimer
Interstate Technology & Regulatory Council (ITRC) guide on "life cycle cost," which is the total project cost across the lifespan of a project, including design, construction, operation and maintenance, and closeout activities.

How to Evaluate Alternative Cleanup Technologies For Underground Storage Tank Sites: A Guide for Corrective Action Plan Reviewers
EPA guidance for state and local regulators that provides information on how to review CAPs that propose alternative cleanup technologies.

Remediation Process Optimization: Identifying Opportunities for Enhanced and More Efficient Site Remediation (133 pp, 1.2M, About PDF) Exit EPA disclaimer
Guidance from the Interstate Technology & Regulatory Council Remediation Process Optimization Team on how to use remediation process optimization (RPO) as a tool to evaluate and manage remediation process uncertainty.

RCRA Corrective Actions: Primary steps in RCRA corrective actions and their relationship to the TriadExit EPA disclaimer
Triad Resource Center page on a four-step approach to RCRA corrective action and how the Triad approach is related to these steps.

Risk-Based Decision-Making And Underground Storage Tanks
A summary of the risk-based decision-making (RBDM) process developed by EPA that includes links to national RBDM implementation strategies and implementation support.

Results-Based Approaches To Corrective Action: September 28, 2000
EPA page linking to the draft Results-Based Approaches to Corrective Action Guidance, which is intended to help state regulators and UST owner/operators to understand and incorporate results-based approaches in cleanups.

Tiered Approach to Corrective Action Objectives (TACO) Fact Sheet 7: Tier 2
Illinois Environmental Protection Agency fact sheet on developing remediation objectives using site-specific data with pre-established modeling equations.

Risk-Based Decision Making (RBDM) for the Remediation of Petroleum-Contaminated Sites Exit EPA disclaimer
Oregon Department of Environmental Quality guidance on RBDM to provide a consistent, streamlined decision-making process for evaluating the risk posed to human health and the environment.

Risk-Based Site Evaluation Process Guidance Documents Exit EPA disclaimer
Minnesota Pollution Control Agency guidance outlining a risk-based approach to decision-making during site investigation and remedy selection under the state's Voluntary Investigation and Cleanup (VIC) and Superfund programs.

Introduction To Risk-Based Corrective Action (RBCA) Exit EPA disclaimer
Michigan Department of Natural Resources and Environment definition of RBCA and an explanation of the tiered approach to RBCA as described under ASTM E1739.

Site Cleanup Using Risk-Based Decision Making (6 pp, 131K, About PDF) Exit EPA disclaimer
Oklahoma Department of Environmental Quality document that describes the steps of risk-based decision-making used to determine cleanup requirements for contaminated sites.

Vendor Information Exit EPA disclaimer
EPA CLU-IN page that links to a searchable directory of remediation and characterization technology vendors.

ASTM E1739-95(2010)e1 Standard Guide For Risk-Based Corrective Action Applied At Petroleum Release Sites Exit EPA disclaimer
Industry standard on risk-based corrective action (RBCA), a consistent decision-making process for the assessment and response to a petroleum release based on the protection of human health and the environment.

ASTM E2205 / E2205M - 02(2009)e1 Standard Guide for Risk-Based Corrective Action for Protection of Ecological Resources Exit EPA disclaimer
ASTM Guide on the Eco-Risk-Based Corrective Action process, which involves implementing corrective action in a manner that is protective of ecological resources.

ASTM E2081 - 00(2010)e1 Standard Guide for Risk-Based Corrective Action Exit EPA disclaimer
ASTM guidance on risk-based corrective action at chemical release sites that uses a tiered approach with a focus on protecting human health and the environment.

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Remediation Methodologies

Corrective Action Plans (CAPs) typically include an overview and evaluation of the proposed remediation methodologies. Each alternative is analyzed to address its effectiveness, efficiency, and cost as well as environmental sustainability, and, increasingly, the impact on greenhouse gas emissions. The selection of a remedial solution is optimized to consider the oil and hazardous materials present, the media that is contaminated, the feasibility of achieving cleanup, the potential greenhouse impacts, the cost-benefit of various solutions, and the unique subsurface characteristics at the release site.  Remedial action alternatives are identified by screening various cleanup options to determine which alternative will meet the performance goals of the reviewing agency.  The thorough evaluation of alternatives ensures that the optimal remedial solution is reliable, effective, energy-efficient, and protective of human health and the environment.

Remediation methods for liquids or vapors include free-product recovery as well as passive and active single-phase and multi-phase recovery. Depending on site conditions, it may be possible to collect free product passively, as opposed to using active methods that rely on electricity or pneumatic devices. Passive product collection may be just as effective as active remediation while having significantly lower operational costs and electrical demands and producing lower greenhouse gas emissions. Examples of passive remediation methods may include skimmers, absorbent socks, or floating oil/water separators. Examples of active remediation systems may include soil vapor extraction or groundwater pumping with activated carbon treatment. For soil, some treatment methods require excavation of the soil (ex situ treatment) while others allow soil to remain in place (in situ treatment) for procedures such as in situ oxidation or bioremediation. Excavated soil may even be reused in the making of asphalt.

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Interstate Technology & Regulatory Council (ITRC) Exit EPA disclaimer
The ITRC is a coalition of state environmental regulators working with federal partners, industry, and stakeholders to advance innovative environmental decision-making.

Evaluating LNAPL Remedial Technologies for Achieving Project Goals (144 pp, 986K, About PDF) Exit EPA disclaimer
Interstate Technology & Regulatory Council (ITRC) Technical/Regulatory Guidance to help stakeholders select the best-suited LNAPL remedial technology for an LNAPL site and help the regulator and others understand what technologies apply in different site situations.

New England Interstate Water Pollution Control Commission (NEIWPCC) – Underground Storage Tanks Exit EPA disclaimer
NEIWPCC, a not-for-profit interstate agency, is involved in local and national underground storage tank issues and also publishes LUSTLine, a national bulletin covering UST/LUST issues, federal and state programs and activities, and technologies.

Above Ground Treatment Technologies (26 pp, 578K, About PDF) Exit EPA disclaimer
Interstate Technology & Regulatory Council (ITRC) document that discusses the basics of optimization of above ground technology for extracted groundwater, air sparging/soil vapor extraction, and multi-phase extraction.

Remediation/Cleanup Technologies
EPA information to help select an appropriate corrective action technology; includes numerous links to EPA remediation and cleanup information, technology verification, and non-EPA remediation and cleanup information.

Green Remediation: Incorporating Sustainable Environmental Practices into Remediation of Contaminated Sites (56 pp, 814K, About PDF) Exit EPA disclaimer
EPA Technology Primer on the basics of green remediation and how to reduce the negative environmental effects of cleanup activities by using a "whole-site" approach.

CLU-IN Remediation Technologies Exit EPA disclaimer
EPA CLU-IN home page on remediation technologies that includes links to information on remediation technologies, project and site profiles, case studies, a technology screening matrix, newsletters, and how to select an innovative cleanup technology.

CLU-IN Green Remediation Focus Exit EPA disclaimer
EPA CLU-IN page on green remediation that provides links to policies and strategies, incorporating best management practices, green remediation in the news, and more.

Greener Cleanups Exit EPA disclaimer
Illinois Environmental Protection Agency site on greener cleanups that includes guiding principles, strategies, and a decision tree.

Biofuels Compendium - Biodiesel – Remediation
Remediation of biodiesel in soil and groundwater, a section of the EPA Biofuels Compendium.

Biofuels Compendium - Ethanol - Remediation
Ethanol remediation section of EPA's Biofuels Compendium.

OSWER Directive 9200.4-17P: Use of Monitored Natural Attenuation at Superfund, RCRA Corrective Action, and Underground Storage Tank Sites (EPA, 1999) (41 pp, 278K, About PDF)
EPA OSWER Directive regarding EPA's policy on the use of monitored natural attenuation for remediation of contaminated groundwater and soil.

Innovative Technologies, Contaminant Focus Exit EPA disclaimer
EPA CLU-IN site on cleanup information organized by contaminant and contaminant groups.

Innovative Technologies, Technology Focus Exit EPA disclaimer
EPA CLU-IN site on cleanup information organized by particular technologies that may be used in a variety of applications.

How to Evaluate Alternative Cleanup Technologies For Underground Storage Tank Sites: A Guide For Corrective Action Plan Reviewers
EPA manual that discusses different alternative cleanup technologies, including soil vapor extraction (SVE), air sparging, biosparging, landfarming, biopiles, bioventing, low-temperature thermal desorption, natural attenuation, dual-phase extraction, in-situ groundwater bioremediation, enhanced aerobic bioremediation, and chemical oxidation.

Green Remediation Best Management Practices: Soil Vapor Extraction & Air Sparging (4 pp, 131K, About PDF) Exit EPA disclaimer
CLU-IN fact sheet on designing, constructing, operating, and monitoring a soil vapor extraction system or air sparging system.

ASTM E1943-98(2010) Standard Guide for Remediation of Ground Water by Natural Attenuation at Petroleum Release Sites Exit EPA disclaimer
ASTM guide for determining the appropriateness of remediation by natural attenuation and implementing remediation by natural attenuation at a given petroleum release site.

API 1628 Set: A Guide to the Assessment and Remediation of Underground Petroleum Releases Exit EPA disclaimer
API Publ 1628A - Natural Attenuation Processes
API Publ 1628B - Risk-Based Decision Making
API Publ 1628C - Optimization of Hydrocarbon Recovery
API Publ 1628D - In-Situ Air Sparging
API Publ 1628E - Operation and Maintenance Consideration for Hydrocarbon Remediation Systems
A comprehensive American Petroleum Institute (API) guide on the assessment and remediation of underground petroleum releases.

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Light Non-Aqueous Phase Liquid Recovery

When pure gasoline or fuel is floating on the groundwater surface, the product needs to be recovered as quickly and efficiently as possible. The longer it stays in the ground, the greater the chance of migration into utilities, drinking water wells, or indoor spaces. Free-floating petroleum is often referred to as Light Non-Aqueous Phase Liquid (LNAPL) Exit EPA disclaimer. The thickness of LNAPL varies considerably as the water table rises and falls. When groundwater subsides, LNAPL thickness tends to be greatest. LNAPL can be removed through excavation, withdrawn by active or passive collection equipment, or chemically oxidized in situ.

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Answers to Frequently Asked Questions About Managing Risk at LNAPL Sites (24 pp, 5.2M, About PDF) Exit EPA disclaimer
American Petroleum Institute (API) document of frequently asked questions and answers about light non-aqueous phase liquids.

A Decision-Making Framework for Cleanup of Sites Impacted with Light Non-Aqueous Phase Liquids (LNAPL) (86 pp, 1.3M, About PDF) Exit EPA disclaimer
Non-Aqueous Phase Liquid (NAPL) Cleanup Alliance document prepared as a guide for long-term management of light, non-aqueous phase liquid (LNAPL) at impacted sites.

Light Non-Aqueous Phase Liquid (LNAPL) Resource Center Exit EPA disclaimer
Information portal compiled by the American Petroleum Institute (API) on LNAPLs, including answers to frequently asked questions, manuals, software, and technical reports.

LNAPL Distribution and Recovery Model (LDRM) Exit EPA disclaimer
American Petroleum Institute's LNAPL Distribution and Recovery Model (LDRM) simulates the performance of proven hydraulic technologies for recovering free-product petroleum liquid releases to groundwater.

How To Effectively Recover Free Product At Leaking Underground Storage Tank Sites: A Guide For State Regulators
EPA technical guidance document to help state regulators and cleanup contractors review those parts of an UST corrective action plan that propose free-product-recovery technologies.

API Interactive LNAPL Guide Exit EPA disclaimer
American Petroleum Institute electronic information system designed to provide an approach for evaluating LNAPL at a site: assessing its potential risk, quantitatively defining mobility and recoverability, developing remedial strategies, and examining methods to enhance site closure opportunities.

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Performance Monitoring

The selected corrective action must be monitored and evaluated for both cost control and achievement of objectives throughout implementation. Performance monitoring approaches will vary depending on the situation. If surface water has been impacted, periodic monitoring of aquatic organisms, plants, or sediments may be undertaken. In the case of groundwater, many government agencies require semi-annual or quarterly reporting to document the performance of the selected action because of variation in groundwater contamination levels at different times of the year. Indoor air monitoring may be conducted more frequently in the wintertime because of the “stack effect” that occurs in buildings when they are closed during cold weather resulting in less air flow. If a particular action does not appear to be effective, an alternative corrective action may be proposed by the tank owner or operator.

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Characterization and Monitoring Technologies Exit EPA disclaimer
EPA CLU-IN site that lists and describes many resources on characterization and monitoring technologies.

The Pay for Performance (PFP) Toolbox
EPA information on 'pay for performance' contracting (i.e., paying contractors a set amount of money for reaching specific cleanup goals within a set time limit predetermined by state experts.)

Performance-Based Management - Fifth in a Series of Remediation Process Optimization Advanced Topics (22 pp, 600K, About PDF) Exit EPA disclaimer
Interstate Technology & Regulatory Council (ITRC) technology overview of the basic concepts of performance-based management.

Air Force Center for Engineering and the Environment - Sustainable Remediation Tool Exit EPA disclaimer
Air Force Center for Engineering and the Environment tool to help plan for the implementation of remediation technologies at a site, evaluate the optimization of remediation technology systems, and compare remediation approaches based on sustainability metrics.

Remediation Optimization Exit EPA disclaimer
EPA CLU-IN site with information on remediation optimization, which uses defined approaches to improve the effectiveness and efficiency with which an environmental remedy reaches its stated goals.

Data Management, Analysis, and Visualization Techniques - Fourth in a Series of Remediation Process Optimization Advanced Topics (22 pp, 563K, About PDF) Exit EPA disclaimer
Interstate Technology & Regulatory Council (ITRC) document that introduces the basics of data management, analysis, and visualization techniques.

Improving Environmental Site Remediation Through Performance-Based Environmental Management (144 pp, 3.4M, About PDF) Exit EPA disclaimer
The Interstate Technology And Regulatory Council (ITRC) guidance on performance-based environmental management that includes regulatory and stakeholder preferences.

Glossary And Terms: Indoor Air Quality in Homes/Residences
EPA glossary of terms related to indoor air quality in homes and residences.

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Institutional And Engineering Controls

Institutional controls (ICs) are non-engineered instruments, such as administrative and legal controls, that help minimize the potential for human exposure to contamination and/or protect the integrity of the remedy. Although it is EPA's expectation that treatment or engineering controls will be used to address principal threat wastes and that groundwater will be returned to its beneficial use whenever practicable, ICs play an important role in site remedies because they reduce exposure to contamination by limiting land or resource use and guide human behavior at a site. For instance, zoning restrictions prevent site land uses, like residential uses, that are not consistent with the level of cleanup.

Institutional controls are meant to be used in conjunction with treatment or engineering controls Exit EPA disclaimer such as containment. Engineering controls are the physical structures that limit or restrict exposure to contamination in the short term or for extended future use. Typically they are well-engineered barriers, such as a reinforced concrete slab constructed in the ground to prevent access to contamination and reduce the exposure pathway.

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Institutional Controls
EPA Web site with links to guidance documents for community members, site managers, and other decision-makers on the types of institutional controls and their role.

Institutional Controls: A Site Manager's Guide to Identifying, Evaluating and Selecting Institutional Controls at Superfund and RCRA Corrective Action Cleanups (32 pp, 221K, About PDF)
EPA fact sheet describing the types of institutional controls (IC) that are commonly available, their strengths and weaknesses, and key considerations, as well as the relationship between IC and engineering controls.

Understanding the Role of Institutional Controls at Brownfields Sites: Major Concepts and Issues Exit EPA disclaimer
Web page describing institutional controls at a glance.

ASTM E2435 – Standard Guide for Application of Engineering Controls to Facilitate Use or Redevelopment of Chemical-Affected Properties Exit EPA disclaimer
ASTM guide that discusses the application of engineering controls to allow the use or redevelopment of properties containing chemical-affected soil, groundwater, or other media.

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Documentation And Reporting

Reporting requirements for corrective actions can vary among implementing agencies. Corrective actions generally must be documented and filed with the appropriate government agency. Some agencies require that the performance of an implemented action be periodically reviewed and evaluated to justify continuing the action. Field documentation is conducted to meet this requirement through field notes, photographs, and performance monitoring. It is also important to develop and review a health and safety plan to protect workers who are involved in the action.

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Regulations Pertaining To Underground Storage Tanks (40 CFR Part 280): Subpart E – Release Reporting, Investigation, And Confirmation
Federal regulations addressing the reporting of suspected releases, investigation and confirmation of the suspected release, and reporting and cleanup of spills and overfills.

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Case Studies

Case studies of various corrective actions are often provided by government agencies and industry associations to assist responsible parties and their consultants in selecting the most efficient and cost-effective action for a particular release. EPA maintains a comprehensive Web site to evaluate innovative corrective actions at CLU-IN Exit EPA disclaimer.

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Cost and Performance Case Studies Exit EPA disclaimer
Federal Remediation Technologies Roundtable site with case study reports that describe the performance and cost of technology applications at large scale and full scale demonstration projects.

Profiles And Case Studies of Green Remediation Exit EPA disclaimer
EPA CLU-In site that links to numerous site-specific project profiles that demonstrate green remediation strategies.

Remediation Technology Demonstration Project Profiles Exit EPA disclaimer
EPA searchable database of thousands of on-going and completed remediation technology demonstration projects.

Characterization and Monitoring Demonstration Project Profiles Exit EPA disclaimer
EPA searchable database of thousands of on-going and completed characterization and monitoring technology demonstration projects.

Greener Cleanup Case Studies
EPA site that features case studies and links to sites that contain many case studies of successful green cleanups.

Reusing Cleaned Up Petroleum Sites
EPA page with numerous examples of how petroleum brownfield sites are being reused, reuse success stories, and information on the redevelopment process.

Use of Risk Assessment in Management of Contaminated Sites (249 pp, 6.2M, About PDF) Exit EPA disclaimer
Interstate Technology & Regulatory Council (ITRC) report on the use of risk assessment and risk-related practices in the management of contaminated sites through a series of case studies.

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