CERCLA sites are generally addressed on an individual basis. However, CERCLA, as amended by SARA, section 104(d)(4) allows EPA to treat
noncontiguous facilities as one site for the purpose of taking response actions when the facilities are related on the basis of geography, or on the basis
of the threat or potential threat to the public health or welfare, or the environment. Section 104(d)(4) of the statute refers to combining
noncontiguous CERCLA ?facilities," but for all practical purposes, the term "site" is synonymous with "facilities." This means that wastes from
several Superfund sites can be managed in a coordinated fashion at one of the sites and still be an "on-site" action, within the permit waiver criteria of
CERCLA section 121(e)(1). Or, a combined response action may combine separate CERCLA sites into one large study area for development of a
joint ground water remedial investigation and feasibility study (RI/FS) and remediation. The goal of this fact sheet is to explain to CERCLA site
managers what factors, benefits, and limitations are associated with taking a combined response action approach. Highlights 1 and 2 include case
studies of combined response actions. Highlight 3 provides a list of sites for which combined response actions are being conducted. Combined
response actions may be more cost effective and expeditious to undertake, since one set of resources is used to carry out two or more related (but
distinct) cleanups. In addition, the permit waiver in CERCLA section 121(e)(1) applies to response activities conducted "on-site," including all
portions of an aggregated site; therefore, the management of wastes between aggregated noncontiguous sites may be conducted without a permit.
United States	Office of	Superfund Publication: Directive No.
Environmental Protection Solid Waste and	9355.3-14FS
Agency	Emergency Response	April 1992
Selecting a Combined Response
Action Approach for Noncontiguous
CERCLA Facilities to Expedite
Cleanups
Office of Emergency and Remedial Response
Hazardous Site Control Division OS-220W	Quick Reference Fact Sheet
Q1. What Is a Combined Response Action for
Noncontiguous Facilities?
A A Combined response action is an approach to remediation
that uses one central site for remediation of wastes from
multiple CERCLA facilities (or sites). Or, a combined
response action is the grouping of separate sites into one
study area because they contribute contamination to the
same aquifer or surface water source. In either case, one
RI/FS is typically developed for the combined response
action. Combining response actions at two or more
noncontiguous CERCLA sites allows the cleanup effort to
proceed in a more timely and cost-effective manner.
Q2. Under What Authority Can This Type of
Action Be Applied?
A For the purposes of taking a response action, EPA can
combine two or more noncontiguous facilities (or sites) that
are reasonably related based on geography or the threat or
potential threat to human health or welfare, or the
environment. CERCLA section 104(d)(4) provides EPA with
broad discretion to treat noncontiguous facilities as one site
for the purposes of response actions. The permit waiver in
CERCLA section 121(e)(1) applies to response actions
conducted "on-site," including all portions of an aggregated
site. In addition, the Preamble to the NCP provides a detailed
discussion on the use and limitations of this combined
approach (See 55 FR 8690, March 8, 1990).
Q3. What Are the Key Benefits Associated
With This Approach?
A There are several potential benefits associated with a
combined response approach. First, it may be more cost
effective to apply treatment at a central location rather than
at numerous individual sites. For example, one incinerator
will be used at the Times Beach site to treat
dioxin-contaminated soils from numerous CERCLA dioxin
sites in Missouri. Time and resource savings attributed to
combining response actions for noncontiguous CERCLA
sites may be achieved from the development of a single
RI/FS, Record of Decision, remedial design, and remedial
action for multiple sites.
A combined response action approach may be highly
favored by the State and Public in cases where sites are near
residential areas and where wastes will be transported to a
different CERCLA site for treatment and disposal.
(Alternatively, this approach may be disfavored
by the community that hosts the site to which
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The Aberdeen Pesticide Dumps Site, North Carolina: A Case Study
This site is comprised of five noncontiguous areas that are reasonably close together—all areas are within a three-mile radius.
The wastes are similar or identical and are appropriate for like treatment. In addition, all areas are related on the basis of the
threat or potential threat to the human health, welfare, and the environment. Initially, this site was considered as five separate
areas listed as one site. Four removal actions were conducted between 1985 and 1989. The material removed from two areas in
1988 and 1989 was stock piled on-site.
In May 1991, a feasibility study was conducted, which supported the use of the centrally-located area for remedy
implementation. This was substantiated by the economic impracticability of conducting treatment at each area. Excavation of
contaminated soil is required at each area, or operable unit, comprising the site. The selected remedy for this site involves
on-site thermal treatment of the contaminated soil, analysis of thermal treatment ash, and on-site disposal. Treatment will be
conducted at a central location on-site, which was chosen based on the presence of the largest volume of contaminated soil at
the selected area, transportation costs from noncontiguous sites, short-term risk to residents associated with transportation,
and noise pollution considerations. Treatment at the centrally-located site area was determined to be more cost effective and
efficient and provides the greatest opportunity for achieving a sound and expeditious environmental cleanup at the site.
Following EPA's issuance of a CERCLA section 106 Administrative Order in March 1990, the PRP agreed to implement the
remedy for the stockpiled excavation materials at one of the areas. After sampling the stockpile, the PRP requested a delay in
implementing the remedy to analyze the viability of combining the remedial process and using one treatment technology at a
central location. EPA granted the extension based on the potential cost savings if it was subsequently determined that one
treatment technology was appropriate to address the soil problems at more than one area.
waste will be sent for treatment.) Also, while the treatment
system is being designed at the central location, wastes
from other noncontiguous sites can be excavated and
transported to the central facility. If treated soil will be
managed at the central facility instead of being hauled
back to the satellite sites, site deletions from the NPL can
proceed for the satellite sites. With this approach two or
more contaminated sites may be addressed in the same
amount of time needed for one cleanup. Note, however,
that there may be PRP opposition based on the perception
that PRPs for one site may become PRPs for other
aggregated sites (SeeNCP 55 FR 8691). Similarly, PRPs for
the "receiving" facility may be concerned if the combined
action results in on-site waste to manage long-term (i.e.,
responsibilities for O&M of a larger facility). (Some of
these concerns may be rebuttable where economies of
scale can be shown.)
Q4. What Are the Criteria For Considering a
Combined Response Action?
A. The decision to combine noncontiguous sites for the
purposes of taking a response action should generally
consider the following factors: 1) nature of the
contamination, 2) geographic locations of the facilities, 3)
compatibility of wastes selected for the treatment or
disposal approach, 4) the cost effectiveness of the
aggregated response, 5) enforcement considerations, and
6) public acceptance.
If a combined response action will be taken for the
treatment of CERCLA wastes, the foremost factor is
whether the contaminants are related such that the
combined treatment or management would be effective
and protective of human health and the environment. (For
example, if thermal treatment is selected for organic
wastes, high concentrations of inorganic wastes may not
be compatible for thermal treatment, would likely require
post-treatment, and thus may not be a good candidate for
aggregation.) Also, if treated soils will be managed at the
site where treatment is conducted instead of being
returned to the individual sites, the implementation time to
complete the remedial action and the costs would be less.
EPA may consider adopting a combined response action
approach based on geography. For example,
noncontiguous CERCLA sites may represent significant
sources of contamination to a common ground water
aquifer. The decision to combine the ground water RI/FS
and remedial action for these facilities may be based on a
commingled contaminant plume.
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HIGHLIGHT Z
Example of Combining Response Actions
at Noncontiguous Facilities
Advanced Micro Devices/Signetics TRW Microwave, California
10 miles
¦ Oakland
San (
Francisco
• Hay ward
Fremont
San Mateo
Palo Alto •
Mountain View * I I
Sunnyvale jJAp
AREA
San
Jose
Study Area
AMD
STEWART
Legend:
m CERCLASite
This map shows an example of three separate CERCLA sites that have been combined into one large
study area site. Each of the separate facilities contributed to ground water contamination. Their
commingled plume was a primary factor in the decision to combine the remedial action for these
facilities. A joint RI/FS was completed and served to further define the ground water contaminant
plume. The Regional Water Quality Control Board adopted an Order approving a joint final Remedial
Action Plan that encompasses cleanup at all three facilities.
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HIGHLIGHT 3


COMBINED
CONTACT


RESPONSE
PHONE
REGION 2
STATE
ACTION
NUMBER
Montclair/West Orange Radium
NJ
Source Treatment
(212) 264-2220
Rockaway Borough Well Field
NY
Ground Water Treatment
(212) 264-0106
REGION 4



Aberdeen Pesticides
NC
Source Treatment
(404) 34 7-7791
ILCO
AL
Source and Ground Water
(404) 257-2643


Treatment

REGION 5



United Scrap Lead
OH
Source Treatment
(312) 886-5877
Janesville Ash Beds/Janesville
WI
Source and Ground Water
(312) 353-9229
Old Landfill

Treatment
(312) 353-9229
Midco I/Midco II
MI
Source and Ground Water



Treatment

Northside Sanitary
IN
Source and Ground Water
(312) 886-4739
landflll/Envirochem

Treatment

REGION 6



Jacksonville Municipal landfill/Rogers
AR
Source Treatment
(512) 255-6664
Road Municipal landfill



REGION 7



Times Beach
MO
Source Treatment
(913) 551-7697
REGION 9



Mt. View/Fair child
CA
Source and Ground Water
(415) 744-2236


Treatment

San Gabriel Area #1, #3, #4
CA
Ground Water Treatment
(415) 744-2257
Monolithic Memories/National
CA
Source and Ground Water
(415) 744-2236
Semiconductor

Treatment

Teledyne
CA
Source and Ground Water

Semiconductor/Specfra-Physics

Treatment
(415) 744-2233

CA
Source and Ground Water

Advanced Micro

Treatment
(415) 744-2231
Devices/Signetics/TRW



Microwave



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The distance between sites may also be a deciding factor
in determining whether grouping is appropriate for waste
treatment and will result in a more efficient cleanup. For
instance, in some cases, taking CERCLA waste to
another site rather than hauling it to a distant commercial
facility may reduce transportation risks. In other cases,
the planned aggregation may lead to increased
transportation and associated risks and thus would be
inadvisable. Also, EPA recognizes that what may be
reasonable distance in a sparsely populated area may be
less reasonable in a more urban setting. For example,
transporting highly volatile wastes through a densely
populated area may pose too high a risk. Transportation
costs also should be considered. Where the cost of
transporting materials from one site to another site may
be prohibitive, this combined approach may not be
cost-effective.
Q5. Can An NPL Site Be Combined With A
Non-NPLSite?
A. Yes, but any remedial action for the combined site must
be accomplished through an enforcement action; no
Fund monies may be spent for remedial actions unless all
portions of the combined site are on the NPL.
Q6. Must the Combined Sites Be Commonly
Owned?
A. No. EPA believes that common ownership is not a
necessary condition for coordinating response actions
at noncontiguous sites. Limiting the applicability of this
approach to commonly owned sites may be unduly
restrictive, with no gain in environmental protection.
However, whether the noncontiguous sites are
commonly owned may be among the factors considered
in determining whether to implement a combined
response. The absence of common ownership may result
in increased obstacles from the land owner of the
"treatment" site as well as other PRPs. Combining
response actions at enforcement-lead sites raises issues
of containment liability and the allocation of resources
and costs. These issues may delay response actions and
should be resolved during the public comment period.
Q7. Is a RCRA Permit Required When a
Combined Response Action Approach
Is Taken?
A. No. One of the benefits of using this type of approach
during cleanup is that wastes from several sites can be
managed in a coordinated method at one site and be
considered an on-site action. An on-site action falls
within the permit waiver criteria of CERCLA section
121(e)(1). For example, if noncontiguous sites A, B, and
C are aggregated, then an on-site treatment facility built
on site A can accept and treat hazardous wastes from
sites B and C without obtaining a RCRA permit for the
treatment unit.
Q8. Must a Combined Response Action
Approach Comply With ARARs?
A. Yes. Even where noncontiguous sites are treated as one
site, activities at the aggregated site must comply with
(or waive) substantive requirements of federal or state
environmental laws that are ARARs. Actual permits are
not required (See Permits and Permit "Equivalency"
Processes for CERCLA On-Site Response Actions,"
OSWER Dir. 9355.7-03, Feb. 19, 1992). However,
transport of hazardous waste fromone site to another is
subj ect to RCRA manifest requirements (See 55 FR 8691,
March 8, 1990).
Q9. Is the Noncontiguous Site Approach
Available For Non-CERCLA Sites?
A. No. The authority to treat noncontiguous sites as one
site is limited under section 104(d)(4) to CERCLA
"facilities," for the purpose of taking a response action
under CERCLA section 104, and the permit waiver is
available only for removal and remedial actions under
CERCLA. Treatment activities performed under other
authorities (or voluntarily) must secure all necessary
permits for on-site and off-site actions.
Q10. What RCRA Regulations Are Relevant
When This Approach Is Used?
A. Although a RCRA permit is not required for response
actions on an aggregated CERCLA site, there are RCRA
regulations that will often be ARARs for on-site
CERCLA response actions. Any cleanup activities that
constitute treatment, storage, or disposal of a hazardous
waste must be in compliance with (or waive) RCRA
regulations that are ARARs (See 55 FR 8691. March 8,
1990). For example, RCRA closure requirements under 40
CFR 264 Subpart G may be ARARs for sites where
hazardous wastes are disposed. In addition, prior to
disposal, land disposal restrictions must be considered
as potential ARARs if the waste is a RCRA hazardous
waste. Beyond ARARs, a combined response action that
requires transporting hazardous waste from one site to
anothermust meet RCRA manifest requirements under 40
CFR 263 (See 55 FR 8691, March 8, 1990.)
Q11. Can A CERCLA Site Manager Combine
An Ongoing Remedial Action With a
Nearby Site?
A. Yes. Ongoing remediation efforts can only be combined
with remediation at newly identified norwontiguous sites
if the criteria for selecting such an approach are
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met. For Fund-lead projects, if noncontiguous sites are
combined, they must all be listed on the NPL (See 55 FR
8690, March 8, 1990). Communities near all of the
noncontiguous sites should be given an opportunity to
comment on the combined approach. The Record of
Decision for the receiving facility (and for the satellite
site as well if a ROD exists) should be amended (or ESDs
issued) to document significant differences from the
original remedial plans, including scheduling, cost, and
transportation issues associated with the combined
response action. If no ROD exists, a proposed plan and
Record of Decision for treatment of wastes from newly
identified noncontiguous sites will be required.
For more information on combining response
actions at noncontiguous sites, contact your
Regional coordinators from OWPE/OERR or Tish
O'Conor at FTS 678-8370.
[Note: These policies set out in this document are intended as
guidance only.]
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