III-137

Managing Hazardous Waste — RCRA Subtitle C SECTION III SECTION III

Chapter 9: Corrective Action to Clean Up Hazardous Waste Contamination

CHAPTER 9

CORRECTIVE ACTION TO CLEAN UP

HAZARDOUS WASTE CONTAMINATION

Superfund National Priorities List (NPL) (as

discussed in Section VI, Chapter 2). The degree of

investigation and subsequent corrective action

necessary to protect human health and the

environment varies significantly among these

facilities.

EPA enforces the corrective action program

primarily through the statutory authorities

established by HSWA. Prior to HSWA, EPA’s

statutory authority to require cleanup of

hazardous releases was limited to situations where

the contamination presented an “imminent and

substantial endangerment to health or the

environment.” Regulatory authority was limited to

releases identified during ground water monitoring

at RCRA-regulated land-based hazardous waste

units, such as landfills or surface impoundments.

Through HSWA, Congress substantially expanded

EPA’s corrective action authority, allowing the

Agency to address any

releases of hazardous

waste or hazardous

constituents to all

environmental

media at both

RCRA

permitted and

nonpermitted

facilities.

In this chapter...

Overview........................................................... III-137

Corrective Action Authorities ............................ III-138

Corrective Action Components ......................... III-139

- RCRA Facility Assessment ........................... III-139

- Phase I RCRA Facility Investigation ............. III-140

- RCRA Facility Investigation .......................... III-140

- Interim Measures .......................................... III-141

- Corrective Measures Study .......................... III-141

- Corrective Measures Implementation ........... III-141

Subpart S Initiative ........................................... III-142

Contaminated Media ........................................ III-142

Remediation Waste Management .................... III-143

Summary .......................................................... III-143

OVERVIEW

Past and present activities at RCRA facilities

have sometimes resulted in releases of hazardous

waste and hazardous constituents into soil, ground

water, surface water, and air. The Statute

generally mandates that EPA require the

investigation and cleanup, or remediation, of

these hazardous releases at RCRA facilities. This

program is known as corrective action. In 1996,

EPA estimated that approximately 5,000 RCRA

facilities are potentially subject to RCRA corrective

action, over three times the number of sites on the
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 SECTION III SECTION III Managing Hazardous Waste — RCRA Subtitle C

Chapter 9: Corrective Action to Clean Up Hazardous Waste Contamination

CORRECTIVE ACTION AUTHORITIES

One of the keys to understanding the RCRA

corrective action program is knowing how a

facility becomes subject to corrective action (see

Figure III-35). Facilities generally are brought into

the RCRA corrective action process when there is

an identified release of hazardous waste or

hazardous constituents, or when EPA is

considering a facility’s RCRA permit application.

When a facility is seeking a permit, or when a

permit is already in place, EPA can incorporate

corrective action into the permit requirements.

Permitted facilities are required under 40 CFR Part

264, Subpart F, to monitor ground water to detect

and correct any releases from regulated landbased hazardous waste land disposal units (as

discussed in Section III, Chapter 5). HSWA further

expanded EPA’s permit authority for corrective

action to address all environmental media, as well

as releases from areas other than regulated land

disposal units, such as tanks or containers. Permits

issued to RCRA facilities must, at a minimum,

contain schedules of compliance to address these

releases and include provisions for financial

assurance to cover the cost of implementing those

cleanup measures. The HSWA statutory

provisions for addressing corrective action in

permits are as follows:

• Releases from solid waste management units

(SWMUs) – Under the authority of §3004(u) of

the Act, EPA requires corrective action for

releases of hazardous waste or hazardous

constituents from SWMUs in a facility’s

permit. A SWMU is any discernible unit

where solid or hazardous wastes have been

placed at any time, or any area where solid

wastes have been routinely and systematically

released.

• Releases beyond the facility boundary –

§3004(v) of the Act authorizes EPA to impose

corrective action requirements for releases

that have migrated beyond the facility

boundary. This corrective action provision can

be complementary to §3004(u), but it is not

expressly limited to releases from SWMUs.

• Omnibus permitting authority – This provision,

found in §3005(c)(3) of the Act, allows EPA or

an authorized state to include any

requirements deemed necessary in a permit,

including the requirement to perform

corrective action. This authority is particularly

useful at permitted facilities when there is a

release not associated with any particular

SWMU. (Omnibus permitting authority is fully

discussed in Section III, Chapter 5.)

EPA also possesses additional authorities to

order corrective action that are not contingent

upon a facility’s permit. The statutory provisions

to issue corrective action orders are:

• Releases at interim status facilities – §3008(h)

of the Act authorizes EPA to require corrective

action or other necessary measures through an

administrative enforcement order or lawsuit,

whenever there is or has been a release of

hazardous waste or constituents from an

interim status RCRA facility (i.e., a facility that

has not yet received a RCRA permit).

Figure III-35:

CORRECTIVE ACTION AUTHORITIES

AUTHORITY

§3004(u)

§3004(v)

§3005(c)(3)

§3008(h)

§7003

NA

PARTY

Any Handler

Permitted 

TSDF

Interim Status 

TSDF

Any Handler

PROVISION

Voluntary

Decision

Permit

Order/Lawsuit

Order/Lawsuit
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Chapter 9: Corrective Action to Clean Up Hazardous Waste Contamination

• Imminent and substantial endangerment –

This authority, found in §7003 of the Act,

allows EPA, upon evidence of past or present

handling of solid or hazardous waste, to

require any action necessary when a situation

may present an imminent and substantial

endangerment to health or the environment

(i.e., poses significant threat or harm). This

authority applies to all facilities, whether or

not they have a RCRA permit. EPA can waive

other RCRA requirements (e.g., a permit) to

expedite the cleanup process under this

provision.

Corrective action need not always involve

permit requirements or an enforcement order.

Owners and operators of RCRA-regulated facilities

may also volunteer to perform corrective action.

Some activities which may be necessary to

achieve corrective action goals at a facility,

however, may require formal approval by EPA or

the state. EPA, therefore, encourages owners and

operators to work closely with EPA and state

agencies to obtain sufficient oversight during

voluntary cleanup activities.

CORRECTIVE ACTION

COMPONENTS

The corrective action process is structured

around elements common to most cleanups under

other EPA programs: an initial site assessment,

followed by a more extensive characterization of

the contamination, and the evaluation and

implementation of cleanup alternatives, both

immediate and long-term. The specific

components of the RCRA corrective action

program are not dictated by the regulations, but

are instead found in various EPA guidance and

policy documents. Since the steps necessary to

achieve cleanup at a facility will depend on sitespecific conditions, the corrective action process is

highly flexible. Therefore, the following six

components of corrective action should be viewed

as considerations necessary to make good cleanup

decisions, and not goals in and of themselves.

These components may occur in any order, and

not every component is necessary to determine

that no further action is required (i.e., that the

corrective action process has been completed).

■ RCRA Facility Assessment RCRA Facility Assessment

The first component in most cleanup programs

is an initial site assessment, known in the RCRA

corrective action process as a RCRA facility

assessment (RFA). During an RFA, owners and

operators, with oversight by their implementing

agencies, typically compile existing information on

environmental conditions at a given facility,

including information on areas of concern (i.e.,

areas that, based on past facility waste

management activities, might warrant further

investigation for releases), actual or potential

releases, and release pathways (e.g., air, soil, or

ground water through which contamination might

possibly travel). This information is compiled and

reviewed to eliminate areas of a facility (even

entire facilities) from further consideration where

there is no evidence of a release or likelihood of a

release that could pose a threat to human health

or the environment. This review may be followed

by a visual site inspection to verify the initial

information. A sampling visit is sometimes

performed to obtain appropriate samples for

making release determinations.

Implementing agencies often use initial site

assessments, such as the RFA, to set priorities for

limited oversight

resources. Since

it could be very

expensive to

oversee all

corrective action

sites at once, EPA

sets priorities to

ensure that it is

RCRA FACILITY

ASSESSMENTS

RFAs compile existing

information on environmental

conditions at a given facility,

including information on actual

or potential releases.
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 SECTION III SECTION III Managing Hazardous Waste — RCRA Subtitle C

Chapter 9: Corrective Action to Clean Up Hazardous Waste Contamination

using its resources in the most effective manner.

In the corrective action program, EPA sets

priorities using a resource management tool called

the National Corrective Action Prioritization

System (NCAPS). NCAPS considers the setting of

a facility, actual and potential releases of

hazardous constituents from the facility, and the

toxicity of constituents of concern, to group

facilities into high, medium, or low priority groups.

In 1996, EPA estimated that 40 percent of all

ranked facilities were high priority, 30 percent

were medium priority, and 30 percent were low

priority. Such groupings do not mean that high

priority facilities will be cleaned up, while those

lower in priority will be ignored or neglected.

Rather, NCAPS is used to provide direction as to

which facilities should be completely cleaned up

first.

■ Phase I RCRA Facility Investigation

Phase I RCRA facility

investigations (Phase I RFIs),

sometimes referred to as

release assessments, are used to

confirm or reduce uncertainty

about areas of concern or

potential releases identified

during the RFA. It is often

useful to conduct a limited release assessment

after the RFA, but before full-scale

characterization, to focus subsequent

investigations or eliminate certain units or areas

from further consideration. In addition, release

assessments can help determine whether interim

measures are needed to contain or minimize the

extent of releases while the corrective action

process is taking place. Release assessments are

particularly helpful in cases where the RFA is

dated or where the overseeing agency and the

facility owner and operator disagree about

inclusion of one or more units, areas, or releases

in the site characterization.

■ RCRA Facility Investigation

If a release is identified during the RFA or the

Phase I RFI, the agency overseeing the corrective

action may instruct the owner and operator of the

facility to conduct

a full-scale site

characterization to

ascertain the

nature and extent

of contamination at

the site. The site

characterization, or

RCRA facility investigation (RFI), should be

tailored to the specific conditions and

circumstances at the facility and should focus on

the units, releases, and pathways of concern. RFIs

can range widely from a small specific activity

(such as investigation of soil contamination

resulting from storage of waste in a specific unit) to

a complex multimedia study that might include a

widespread investigation of releases to

air, soil, and ground water.

To expedite the corrective action

process, EPA encourages facility

owners and operators to use existing

information whenever possible to

avoid duplication of effort. For

example, an owner and operator may

have records of soil borings collected during

construction of a facility. By using existing

information, owners and operators can focus their

investigation on collecting new data necessary to

select and implement cleanup alternatives.

To facilitate investigations, EPA uses the

concept of action levels in some cases. Action

levels are risk-based concentrations of hazardous

constituents in ground water, soil, or sediment.

The presence of hazardous constituents above

these action levels suggests that there has been a

release requiring additional study or corrective

measures. Under this approach, contamination at

PHASE I RCRA FACILITY

INVESTIGATIONS

Phase I RFIs confirm or reduce

uncertainty about areas of

concern or potential releases

identified during the RFA.

RCRA FACILITY

INVESTIGATIONS

RFIs ascertain the nature

and extent of contamination

of releases identified during

the RFA or Phase I RFI.
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Chapter 9: Corrective Action to Clean Up Hazardous Waste Contamination

a site found below appropriate action levels would

not generally be subject to cleanup or further

study.

■ Interim Measures

Interim

measures are

short-term actions

used to control

ongoing risks to

human health or

the environment

while site

characterization is

underway or before a final remedy is selected.

Interim measures can include a wide range of

activities such as removing the source of the

contamination, fencing off the contaminated area,

or providing alternative drinking water sources.

EPA has increasingly emphasized the importance

of implementing interim measures as early as

possible in the corrective action process.

■ Corrective Measures Study

If the potential need

for cleanup is identified

during the RFI process,

the owner and operator

is then responsible for

performing a corrective

measures study (CMS).

During the CMS, the

owner and operator will identify and evaluate

different alternatives to remediate the site. A CMS

need not address all potential remedies; it should

focus instead on realistic remedies tailored to the

nature and extent of the contamination. EPA or

the state agency expects facility owners and

operators to develop and recommend a preferred

remedy or remedy performance standards,

including proposed media cleanup levels and

compliance time frames. Although this

recommendation is the responsibility of the owner

and operator, EPA or the state agency can reject

any alternative and require further analysis or

prescribe a different remedy.

Upon completion of the CMS, EPA or the state

agency generally summarizes the proposed

remedial action plan and the findings supporting

the selected remedy in a document called the

statement of basis. This document is designed to

facilitate public participation in the remedy

selection process. The statement of basis

describes the rationale for the remedy selection

and contains an explanation for the selected

cleanup levels. The scope and content for the

statements of basis vary widely, depending on the

complexity of the site, the nature of the proposed

remedy, the level of public interest, and other

relevant factors. In any case, the statement of

basis should be sufficiently detailed for the public

to understand and comment on EPA’s or the state

agency’s remedy selection decision.

■ Corrective Measures Implementation

Once EPA or the state agency has addressed

public comments, a facility can transition into the

next phase of the

remedial process:

corrective measures

implementation (CMI).

CMI includes detailed

design, construction,

operation, maintenance,

and monitoring of the

chosen remedy, all of

which are performed by

the facility owner and operator with EPA or state

oversight.

INTERIM MEASURES

Interim measures are

short-term actions to

control ongoing risks while

site characterization is

underway or before a final

remedy is selected.

CORRECTIVE

MEASURES STUDY

CMS identifies and

evaluates different

alternatives to

remediate the site. CORRECTIVE

MEASURES

IMPLEMENTATION

CMI includes detailed

design, construction,

operation, maintenance,

and monitoring of the

chosen remedy.
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Chapter 9: Corrective Action to Clean Up Hazardous Waste Contamination

CORRECTIVE ACTION: A CASE STUDY

XYZ Industrial Company is a hazardous waste

storage facility with a RCRA permit. During a

routine EPA inspection, the Agency discovered

contamination in XYZ Industrial’s tank storage area.

Soils under the area were contaminated by wastes

spilled during pumping, and by leaking tanks. The

soil exhibited high levels of trichloroethylene, a

volatile organic compound that migrates easily

through the soil into the ground water and is

believed to cause cancer. In addition, the company

discovered that a municipal drinking water well

located within a mile of the facility was also

contaminated with trichloroethylene. None of this

contamination was detected in the initial permitting

process.

EPA then conducted an RFA to compile

information on the types of hazardous wastes

managed at the facility in the past, areas where

such wastes were managed, and possible exposure

pathways.

The owner and operator of XYZ Industrial then

conducted an RFI, with EPA oversight, to estimate

the health and environmental problems that could

result if the contamination was not cleaned up, and

to determine the extent of the contamination. In

order to protect human health and the environment

while these assessments and investigations were

taking place, the owner and operator established an

alternative drinking water source for the households

served by the municipal well as an interim measure.

A CMS determined that the company should

clean up the ground water via a pump and treat

process, excavate the soil and treat it thermally, and

dispose of the treated soil in a landfill on site.

In a statement of basis, EPA proposed the

above technologies as the recommended remedial

alternative. The statement of basis included all

documentation in support of the recommended

remedy, as well as the contaminant cleanup levels

that had to be achieved during the remedial action.

The public had an opportunity to comment on both

the statement of basis and a draft permit

modification that included the additional activities

that XYZ Industrial would undertake as part of the

remedy process. Following the public comment

period, the facility owner and operator began the

CMI phase of the cleanup by administering the

selected remedy.

SUBPART S INITIATIVE

Presently, EPA implements the RCRA

corrective action program primarily through

statutory authorities and EPA guidance and policy

developed pursuant to those authorities. Only a

very small part of the corrective action program

has been codified as regulations. In 1990, EPA

proposed to incorporate a substantial part of the

corrective action program in 40 CFR Part 264,

Subpart S. The primary objective of Subpart S is

to set forth a clear and comprehensive set of

regulations and procedures that will provide a

more consistent approach to investigating and

making cleanup decisions. EPA has been working

with states and the regulated community to

develop practical, streamlined regulations to

achieve cleanup goals while enhancing public

participation and cost reduction. The Subpart S

regulations will also serve to encourage states to

assume a larger role and to seek authorization for

the corrective action program.

CONTAMINATED MEDIA

Cleaning up RCRA facilities under the

corrective action program may involve the

management of large amounts of contaminated

media, particularly soil and ground water. Under

the contained-in policy (as discussed in Section III,

Chapter 1), media that contain listed hazardous

wastes or exhibit a hazardous waste characteristic

generally are subject to the same management
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Chapter 9: Corrective Action to Clean Up Hazardous Waste Contamination

standards as newly generated hazardous waste,

including TSDF standards and LDR requirements.

These strict management standards sometimes do

not correspond to the level of risk posed by

environmental media, which is often

contaminated with relatively small amounts of

hazardous waste. EPA has proposed HWIR-media

(as discussed in Section III, Chapter I) to finalize

provisions to facilitate the management of such

remediation wastes.

REMEDIATION WASTE

MANAGEMENT

While HWIR-media proposes to facilitate the

management of remediation wastes, the corrective

action program already contains two provisions

designed to address the unique nature of

remediation wastes and facilitate the selection and

implementation of effective cleanup remedies.

The first provision establishes standards for

corrective action management units. A CAMU

is a physical, geographical area designated by EPA

or states for managing remediation wastes during

corrective action. These management provisions

allow remediation waste to be managed in a unit

without having to comply with LDR treatment

standards, or the minimum technical requirements

for land-based treatment, storage, or disposal

units.

The second provision establishes standards for

temporary units (TUs). TUs are containers or

tanks that are designed to manage remediation

wastes during corrective action at permitted or

interim status facilities. These provisions allow

EPA or states to modify the design, operating, and

closure standards that normally apply to these

units in order to facilitate prompt cleanup of

contaminated sites.

SUMMARY

Through a process called corrective action,

EPA requires RCRA-regulated facilities to

investigate and clean up releases of hazardous

waste or constituents to the environment.

 Corrective action is included as a

requirement in a facility’s permit through

§3004(u), §3004(v), or §3005(c)(3) statutory

authorities. Corrective action can also be

mandated through an enforcement order through

§3008(h) or §7003 statutory authorities. Facilities

may also voluntarily choose to clean up their

contamination.

The corrective action process is flexible and

focused on results, rather than specific steps. The

six main components of the corrective action

process generally are:

• The RFA, to compile existing information on

environmental conditions at a given facility,

including information on actual or potential

releases

• The Phase I RFI (also known as a release

assessment), to confirm or reduce uncertainty

about areas of concern or potential releases

identified during the RFA

• The RFI, to ascertain the nature and extent of

contamination of releases identified during the

RFA or Phase I RFI

• Interim measures to control ongoing risks

while site characterization is underway or

before a final remedy is selected

• The CMS, to identify and evaluate different

alternatives to remediate the site

• The CMI, which includes detailed design,

construction, operation, maintenance, and

monitoring of the chosen remedy.
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 SECTION III SECTION III Managing Hazardous Waste — RCRA Subtitle C

Chapter 9: Corrective Action to Clean Up Hazardous Waste Contamination

Two EPA initiatives are aimed at facilitating

corrective action. The Subpart S initiative

proposes to establish the regulatory authorities

and guidance for corrective action as a regulatory

program, in order to provide national consistency.

HWIR-media proposes to finalize provisions to

facilitate the management of such remediation

wastes.

The corrective action program already

contains two provisions designed to address

remediation wastes: standards for CAMUs and

TUs.