United States
Environmental Protection
Agency
Solid Waste and
Emergency Response
Publication No. 9355.4-01 FS
August 1990
vvEPA
A Guide on Remedial
Actions at Superfund Sites
With PCB Contamination
Office of Emergency and Remedial Response
Hazardous Site Control Division (OS-220)
Quick Reference Fact Sheet
GOALS
This fact sheet summarizes pertinent considerations in the development, evaluation, and selection of remedial actions at Superfund sites with
PCB contamination. It provides a general framework for determining cleanup levels, identifying treatment options, and assessing necessary
management controls for residuals. It is not a strict "recipe" for taking action at PCB-contaminated sites, but it should be used as a guide for
developing remedial actions for PCBs. Site-specific conditions may warrant departures from this basic framework. A more detailed discussion
of these issues canbefoundintheGuidance on Remedial Actions for Superfund Sites with PCB Contamination, OSWER Directive No. 9355.4
-01.
SUPERFUND GOAL AND EXPECTATIONS
The Superfund program goal and expectations
for remedial actions (40CFR 300.430 (a)(l)(i)
and (iii)(1990)) should be considered during
the process of developing remedial
alternatives. EPA's goal is to select remedies
that are protec-tive of human health and the
environment, that maintain protection over
time, and that minimize untreated waste. The
Agency expects to develop appropriate
remedial alternatives that:
Use treatment to address the principal
threats at a site, wherever practicable
Use engineering controls, such as
containment, for waste that poses a rela-
tively low long-term threat or where treatment
is impracticable
Use a combination of treatment and
containment to achieve protection of human
health and the environment as appropriate
Use institutional controls to supplement
engineering controls for long-term
management and to mitigate short-term
impacts
Consider the use of innovative tech-nology
when such technology offers the potential for
comparable or superior treatment performance
or implementability,
fewer or lesser adverse impacts than other
available approaches, or lower costs for similar
levels of performance than more demonstrated
technologies
Return usable ground waters to their
beneficial uses wherever practicable, within a
timeframe that is reasonable, given the
particular circumstances of the site
The following sections are organized to
follow the Superfund decision process
from scoping through preparation of the
ROD
DETERMINE DATA NEEDS - Consider Special Characteristics of PCBs
Considerations to note during scoping and
when developing potential remedial
alternatives for PCBs, include the following:
Applicable or relevant and appropriate
requirements (ARARs) for PCBs are relatively
complexbecause PCBs are addressed by both
TSCA and RCRA (and in some cases, state
regulations). Figure 1 illustrates primary
regulatory requirements that address PCBs.
PCBs encompass a class of chlorin ated
compounds that includes up to 209 variations
or congeners with different physical and
chemical characteristics. PCBs were commonly
used as mixtures called Aroclors. The most
common Aroclors are Aroclor-1254,
Aroclor-1260, and Aroclor-1242.
PCBs alone are not usually very mobile.
However, they are often found with oils,
which may carry the PCBs in a separate phase.
PCBs may also be carried with sod particulates
to which they are sorbed.
Although most PCBs are not very
volatile, they are very toxic in the vapor phase.
Consequently, air sampling and analytical
methodologies should be selected that will
allow for detection of low levels of PCBs.
Certain remedial technologies will require
specific evaluations and/or treatability
studies. If biotreatment is considered, the
mobility andtoxicity of possible by-products
should be assessed. If stabilization is
considered, the volatilization of PCBs during
and after the process should be evaluated.
Also, the long-term effectiveness of
stabilization should be evaluated carefully. If
incineration is considered, the presence of
volatile metals should be addressed.
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Figure 1 - Primary Regulatory Requirements/Policies
Addressing PCBs
RCRA
Outlines closure requirements for hazardous
waste landfills (40 CFR 264.310)
Establishes land disposal restrictions for liquid
hazardous waste that contains PCBs at 50 ppm
or greater or nonliquid hazardous waste that
contains total HOCs (including PCBs) at concen-
trations greater than 1,000 ppm (40 CFR 268.32)
Provides for a treatabifity variance (40 CFR
268.44) that may be used for PCBs in CERCLA
soil and debris. (Under Superfund treatability
variance guidance, PCB concentrations should
be reduced to .1 -10 ppm for initial concentra-
tions up to 100 ppm; abovelOO ppm, treatment
should achieve 90-99% reduction of PCBs, con-
sistent with Superfund expectations for treatment.)
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TSCA
Regulates PCBs at concentrations of 50 ppm or
greater (40 CFR 761)'
- PCB management options include: incineration
(40 CFR 761.70), high- temperature boiler (40
CFR 761.60), alternative technology that
achieves a level of performance equivalent to
incineration (40 CFR 761.60), and chemical
waste landfill (40 CFR 761.75)
Note: Liquid PCBs at concentrations of 500 ppm
or greater can only be incinerated or treated by
using an alternative technology equivalent to in-
cineration (40 CFR 761.60). Dredged material
may also be disposed of by a method approved
by the RA (40 CFR 761.60 (a)(5)).
Establishes a PCB spill policy (40 CFR 761.120)
that defines the level of cleanup for recent small-
volume spills. The Superfund approach is
consistent with this policy.
I'WHewwwBW'K'Ow'WW
CERCLA/NCP
Remedial Actions Must:
Protect human health and the environment (121[b][1J)
Comply with applicable or relevant and appropriate
requirements (ARARs) (121[d]{2])
Be cost-effective (40 CFR 300.430) (121 [b][1 ])
Utilize permanent solutions and alternative treatment
technologies or resource recovery technologies to the
maximum extent practicable (40 CFR 300.430) (121[b][1j)
CWA
Establishes requirements and discharge limits
for activities that affect surface water
- WQC for PCBs, chronic exposure through
drinking water and fish ingestion - 7.9 x 10*
ppb based on incremental increase cancer risk
of 10-* over lifetime
- WQC for PCBs, acute toxicity to freshwater
aquatic life « 2 ppb, chronic - .014 ppb
- WQC for PCBs, acute toxicity to saltwater
aquatic life 10 ppb, chronic .03 ppb
SDWA
Establishes MCLs and MCLQs for drinking water
(40 CFR 141)
- Proposed MCL for PCBs - .5 ppb
MCLG for PCBs - 0 ppb
Under the TSCA anti-dilution provision (40 CFR 761.1[b]), PCBs disposed of after 1978 are treated as if they were at their original concentration. However, the
Agency has clarified that the anti-dilution provision is only applicable to Superfund response actions for disposal that occurs as part of the remedial action.
Therefore, PCBs at Superfund sites should be evaluated based on the concentration at which they exist in the environment at the time a response action is
determined (July 1990 memorandum from Don Clay and Linda Fisher).
ESTABLISH PRELIMINARY REMEDIATION GOALS
The following guidelines should be con-
sidered when establishing preliminary
remediation goals (i.e., cleanup levels) for
soils, ground water, and sediment. Exceeding
the levels indicated does not require that
action be taken. These levels should be. used
to define the area over which some action
should be considered once it has been
determined that action is
necessary to protect human health and the
environment These goals may be refined
throughout the RI/FS process; final
remediation goals are determined in the
remedy selection.
Soils
The concentration of concern for PCBs (that
defines the area to be addressed for
soils onsite) will depend primarily on the type
of exposure that will occur based on land
use-current and future residential or industrial.
Guidelines based on generic exposure
assumptions and characteristics of
Aroclor-1254 are provided in Table 1. Other
factors that may affect these levels include the
potential for PCBs to migrate to ground water
and to affect environmental receptors.
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Table 1
Recommended Soil Action Levels-
Analytical Starting Point
Land Use
Residential
Industrial
Concentration (ppm)
1
10-25
The 1 ppm starting point for sites in residential
areas reflects a protective quantifiable
concentration. (Also, be-cause of the
persistence and pervasive-ness of PCBs,
PCBs will be present in background samples at
many sites.) For sites in industrial areas,
action levels generally should be established
within the range of 10 to 25 ppm. The
appropriate concentration within the range will
depend on site-specific factors that affect the
exposure assumptions. For example, at sites
where exposures will be very limited or where
soil is already covered with concrete, PCB
concentrations near the high end of the 10-to
25 ppm range may be protective of human
health and the environment.
Ground Water
If ground water that is, or may be, used for
drinking water has been contaminated by
PCBs,response actions that return the ground
water to drinkable levels should be
considered. Non-zero maximum contaminant
level goals (MCLG) or maximum contaminant
levels (MCL) should be attained in ground
water where relevant and appropriate. State
drinking water standards may also be potential
ARARs. Proposed non-zero MCLGs and
proposed MCLs may be considered for
contaminated ground water. The pro- posed
MCL for PCBs is .5 ppb. Since PCBs are
relatively immobile, their presence in the
ground water may have been facilitated by
solvents (e.g., oils) or by movement on
colloidal particles. Thus, the effectiveness of
PCB removal from ground water, i.e., ground-
water extraction, may be limited. In some
cases, an ARAR waiver for the ground water
may be supported based on the technical im-
practicability of reducing PCB concentrations
to health-based levels in the ground water.
Access restrictions to prevent the use of
contaminated ground water and containment
measures to pre- vent contamination of clean
ground water should be considered in these
cases.
Sediment
The cleanup level established for PCB-
contaminated sediment may be based on
direct-contact threats (if the surface water is
used for swimming) or on exposure as-
sumptions specific to the site (e.g., drink- ing
water supplies). More often, the impact of
PCBs on aquatic life and consumers of aquatic
life will determine the
Table 2 - Sediment Cleanup Levels
cleanup level. Interim sediment quality criteria
(SQC) have been developed for several non-
ionic organic chemicals, in- eluding PCBs and
may be considered in establishing remediation
goals for PCB- contaminated sediments. The
method used to estimate these values is called
the equilibrium partitioning approach. It is
based on the assumptions that: (1) the
biologically available dissolved concen-
tration of a chemical in interstitial water is
controlled by partitioning between sediment
and waterphases that can be estimated based
on organic carbon parti- tion coefficients; (2)
the toxicity of a chemical to, and
bioaccumulation by, benthic organisms is
correlated with the bioavailable concentration
of the chemi- cal in pore water; and (3) the
ambient aquatic life water quality criteria
(WQC) concentrations are appropriate for the
protection of benthic communities and their
uses. Table 2 presents the sediment quality
criteria and derived PCB sediment
concentrations based on the SQC for
freshwater and saltwater environments and
two organic carbon (OC) concentrations.
These criteria are to be considered in
establishing remediation goals for con-
taminated sediments.
Aquatic Environment
Freshwater Saltwater
S«diment Quality Criteria (SQC) 19 33
(Concentrations expressed as ug/g of sediment)
OCs10% 1.90 3.30
OC = 1% 0.19 0.33
DEVELOP REMEDIAL ALTERNATIVES
The potential response options at any site
range from cleaning up the site to levels that
would allow it to be used without restrictions
to closing the site with full containment of the
wastes. Figure 2 illustrates the process for
developing alternatives for a PCB-
contaminated site.
Primary Alternatives
It is the expectation of the Superfund program
that the primary alternatives for a site will
involve treatment of the principal threats and
containment of the remaining low level
material. For residential sites, principal threats
will generally include soils contaminated at
concentrations greater than 100 ppm PCBs.
For industrial sites, principal threats will
include soils contaminated at concentrations
greater than or equal to 500 ppm PCBs.
Treatment Options
Liquid and highly concentrated PCBs
constituting the principal threats at the site
should be addressed through treatment.
Treatment options that are currently available
or are being tested include incineration,
solvent washing, KPEG (chemical
dechlorination), biological treatment, and
solidification. Compliance with TSCA ARARs
requires that PCBs, at greater than SOppm, be
incinerated, treated by an equivalent method,
or disposed of in a chemical waste landfill.
Equivalence to incineration is demonstrated
when treatment residues contain <2 ppm PCB.
If treatment is not equivalent to incineration,
compliance with TSCA ARARs must be
achieved by implementing long-term
management controls consistent with the
chemical waste landfill requirements. (Liquid
PCBs at concentrations greater than 500 ppm
cannot be landfilled under TSCA.)
Containment of Low-Threat Material
Long-term management controls should
generally be implemented for treatment
residuals and other low level contaminated
materials remaining at the site. Example
scenarios for the use of long-term
management controls appropriate for
particular PCB concentrations are shown in
Table 3. The substantive requirements of a
chemical waste landfill specified in TSCA
regulations (761.75
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(b)) are indicated, along with the justification
that should be provided when a specific
requirement is waived under TSCA (761.75
(c)(4) (Under CERCLA on-site actions must
meet substantive, but not procedural,
requirements of other laws.) TSCA requires that
PCBs that are not incinerated or treated by an
equiv lent method be disposed of in a chemical
waste landfill; it may be appropriate to waive
certain landfill requirements, where treatment has
reduced the threat posed by the material
remaining at the site, as is indicated in Table-3.
Exceptions
Treatment of low-threat material may be
warranted at sites involving:
Relatively small volumes of contaminated
material
Sensitive environments (e.g., wetlands)
Floodplains or other conditions that make
containment unreliable.
In these cases, long-term management controls
may be reduced, as shown in Table 3, since the
concentrations are lower.
Containment of principal threats may be
warranted at sites involving:
Large volumes of contaminated material for
which treatment may not be practicable
PCBs mixed with other contaminants that
make treatment impracticable
Highly concentrated PCBs that are difficult to
treat because of their inaccessibility (i.e.,buried
in a landfill)
Figure 2 - Key Steps In the Development of Remedial Alternatives for PCB-Contaminated Superfund Sites*
What Is the action area
assuming unlimited exposure?
*%,.** #A
10-25ppmPCB
or greater
K«y
ft
A
XXX
O
Residential
Industrie!
Containment
Action Area
Boundary
What are principal threats to be treated?
(PCBs at 500 ppm or greater, or more than 2 orders of magnitude above the action level.)
Treat principal threats at least to levels that are to be contained (90-99% Reduction)
pppm
100 ppm
orgreater
l-100ppm
500 ppm
or greater \io-500ppm
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SELECTION OF REMEDY
Criteria and Balancing
The analysis of remedial alternatives for
PCB-contaminated Superfund sites is
developed on the basis of the following nine
evaluation criteria provided in the NCP
(300.430[e][a][iii];300.430[f][i][i]).
Considerations unique to PCBs are noted
Threshold Criteria
Overall protection of human health
and the environment. Are all pertinent
exposure pathways being addressed?
Are highly concentrated PCBs being
treated? Are remaining PCBs and
treatment residuals being properly
contained, as outlined in Table 3?
Compliance with ARARs. Does the
action involve disposal of PCBs at con-
centrations greater than or equal to 50
ppm? Is the action consistent with TSCA
treatment requirements? Is the action
consistent with chemical waste landfill
requirements, with appropriate TSCA
waivers specified for landfilling of
material that doesnot meet treatment re-
quirements? Is a RCRA hazardous waste
present? Do California List land dis-
posal restrictions (LDRs) apply? Is the
action consistent with LDRs or treat-ability
variance levels where appropriate? Is
contaminated ground water that is
potentially drinkable being returned to
drinkable levels or is support for a technical
impracticability waiver provided?
Balancing Criteria
Long-term effectiveness and perm-
anence. Are highly concentrated PCBs
Table 3 - Selection of Long-Term Management Controls To Be Considered for PCB-Contaminated Sites
being treated? Are low-concentration
PCBs being properly contained, as out-
lined in Table 3? Is the site in a location
that geographically limits the long-term
reliablility of containment (e.g., high
water table, floodplain)?
Reduction of toxicity, mobility, or
volume through treatment. Is there a
high degree of certainty that the treat-
ment methods selected will achieve at
least a 90 percent reduction of PCBs?
Does treatment increase the volume of
PCB-contaminated material thatmust be
addressed either directly (e.g., solidifi-
cation) or through the creation of addi-
tional waste streams (e.g., solvent wash-
ing)?
Short-term effectiveness. Istheshort-
term inhalation risk resulting from vola-
tilization of the PCBs properly addressed?
What is the relative timing of the differ-
ent remedial alternatives?
Implementability. Does the treatment
selected require construction of a system
onsite (e.g., KPEG, solvent washing)?
Doesthe action require extensive study to
determine effectiveness (e.g., biore-
mediation)? Are permitted facilities
available for Alternatives involving off-
site treatment or disposal?
Modifying Criteria
State acceptance
Community acceptance
Likely Tradeoffs Among Alternatives
Primary tradeoffs for PCB -contaminated
sites will derive from the type of treat-
ment selected for the principal threats and
the determination ofwhatmaterialcanbe
reliably contained. Alternatives that
require minimal long-term management
will often provide less short-term
effectiveness and implementability be-
cause large volumes of contaminated
material must be excavated and treated.
They will generally be more costly but
will provide highlong-term effective-ness
and permanence and achieve significant
reductions in toxicity andvolumethrough
treatment. Alternatives that involve
containment of large portions of the
contaminated site will generally have
lower long-term effectiveness and per-
manence and achieve less toxicity or
volume reduction through treatment.
However, they will generally be less
costly, more easily implemented, andhave
higher short-term effectiveness.
DOCUMENTATION
A ROD for a PCB-contaminated Super-
fund site should include the following
components under the Description of
Alternatives section:
Remediation goals defined in the FSfor
each alternative, i.e., concentrations
above which PCB-contaminatedmate rial
will be addressed and concentrations
above which material will be treated.
Treatment levels to which the selected
action will reduce PCBs before redepos-
iting residuals. The consistency of these
levels withTSCA requirements and other
ARARs should be indicated.
Long-term management controls that will
be implementedto contain or limit access
toPCBsremainingonsite. The consistency
with RCRA closure and TSCA chemical
waste landfill requirements (and
justification for appropriate TSCA
waivers) should be indicated.
NOTICE
Development of this document was fundedby the United States Environmental Protection
Agency. It has been subjected to the Agency's review process and approved for
publication as an EPA document.
The policies and procedures set out in this document are intended solely for the guidance
of response personnel. They are not intended nor can they be relied upon, to create any
rights, substantive or procedural, enforceable by any party in litigation with the United
States. EPA officials may decide to follow this guidance, or to act at variance with these
policies and procedures based on an analysis of specific site circumstances, and to
change them at any time without public notice.
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