Section 121(d) of CERCLA, as amended by the 1986 Superfund Amendments and Reauthorization Act (SARA),
requires that on-site remedial actions must at least attain Federal and more stringent State applicable or relevant and
appropriate requirements (ARARs) upon completion of the remedial action. The 1990 National Contingency Plan (NCP)
requires compliance with ARARs during remedial actions as well as at completion, and compels attainment of ARARs
during removal actions whenever practicable. See NCP, 55 FR 8666, 8843 (March 8, 1990) (to be codified at 40 CFR
section 300.414(i)), and 55 FR 8666, 8852 (March 8, 1990) (to be codified at 40 CFR 300.435(b)(2)).
To implement the ARARs provision, EPA has developed guidance, CERCLA Compliance With Other Laws Manual:
Parts I and II (Publications 9234.1-01 and 9234.1-02), and has provided training to Regions and States on the identification
of and compliance with ARARs. These "ARARs Q*s and A's" are part of a series of Fact Sheets that provide answers to
a number of questions that arose in developing ARAR policies, in ARAR training sessions, and in identifying and complying
with ARARs at specific sites. This particular Q's and A's Fact Sheet addresses compliance with Federal Water Quality
Criteria (FWQC) as ARARs.
United States s Office of
Environmental Protection Solid Waste and
Agency Emergency Response
Publication 9234.2-09/FS
June 1990
&EPA
ARARs Q's & A's:
Compliance With Federal
Quality Criteria
Water
Office of Emergency and Remedial Response
Office of Program Management OS-240
Quick Reference Fact Sheet
Qt. What are the Federal Water Quality Criteria?
A Federal Water Quality Criteria (FWQC) are
nonenforceable guidance established by EPA for
evaluating toxic effects on human health and aquatic
organisms. FWQC are used or considered by the
States in setting their water quality standards (WQSs)
for surface water. State WQSs consist of designated
uses (i.e., fishing, swimming, drinking water) and
criteria for pollutants set at levels that are protective
of those uses. State WQSs are regulatory require-
ments, and permit limits are established to ensure
that the State use designations and criteria are met
There are two categories of FWQC that relate to
human exposure:
Ingestion of contaminated drinking water and
contaminated fish; and,
Ingestion of contaminated fish alone.
informational purposes and do not represent an
Agency judgement on an "acceptable" risk level.
In addition to the FWQC published for two human
exposure scenarios, FWQC are published for four
other categories. They consist of acute and chronic
toxicity for fresh and saltwater aquatic life.
Q2. Do FWQC constitute potential ARARs for
Superfund sites?
A. Yes, Although compliance with FWQC is not legal-
ly required at non-Superfund sites, and they are not
"legally applicable" requirements under CERCLA,
FWQC may be ARARs when found by the Agency
to be relevant and appropriate (see final NCP
preamble, 55 FR at 8742 (March 8, 1990).
Specifically, CERCLA section 121(d)(2)(A) states
that every remedial action "shall require a level or
standard of control which at least attains ... water
quality criteria established under section 304 or 303
of the Clean Water Act, where such ... criteria are
relevant and appropriate under the circumstances of
the release or threatened release."
FWQC have been published for many different con-
taminants (both noncarcinogens and carcinogens).
FWQC for noncarcinogens are generally set above
zero, and address chronic and toxic effects. FWQC
for carcinogens are recommended at zero, although a
range of concentrations corresponding to incremental
cancer risks of 10'5, 10"6, and 10"7 are provided for
Q3. When are FWQC best suited to serve as cleanup
standards?
A FWQC for specific pollutants should generally be
identified as ARARs for surface-water cleanup if
Printed on Recycled Paper
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particular circumstances exist at the site that FWQC
were specifically designed to protect, unless the State
has promulgated WQSs for the specific pollutants
and water body at the site. Standards that are
specifically suited to site circumstances should
generally be used to establish cleanup levels at sites
where those circumstances are present.1 A State
WQS may be a site-specific adaptation of a FWQC.
In such cases, they are generally the appropriate
standards for the specific pollutant and water body,
rather than the FWQC. In the absence of any State
WQSs specific to the pollutant and water body of
concern, FWQC may be ARARs for surface-water
bodies when:
Protection of aquatic life is a concern. Examples
include sites where:
adverse impacts to aquatic life are foreseen
at the site; or
the surface-water bodies are designated for
the protection of aquatic life.
Human exposure from consumption of
contaminated fish is a concern.
For sites where protection of aquatic life is a concern,
the FWQC for fresh or saltwater aquatic life
(whichever is pertinent) may be ARARs. When
human exposure from consumption of contaminated
fish is a concern (e.g., sites that require remediation
of-recreational water bodies, saltwater bodies, or
estuaries used for fishing), the FWQC published for
human exposure from consumption of fish may be
ARARs for the sites. Examples include sites where
the surface-water bodies are used for fishing and an
exposure route consists of consumption of contam-
inated fish from the site.
Note, however, that if any of the above-mentioned
water bodies are also used for drinking, standards for
acceptable levels of contaminants in drinking water
may also be potential ARARs for the site (e.g., non-
zero maximum contaminant level goals (MCLGs),
maximum contaminant levels (MCLs), State WQSs
designated for drinking-water use, and FWQC
adjusted to reflect cleanup standards for drinking
water). (Question #5 of this fact sheet addresses
how to determine the ARAR in these situations,
when there are both drinking-water and environ-
mental concerns at the site.)
1 See proposed NCP preamble, 53 PR at 51442 (Dec. 21,1988), and the
final NCP preamble, 55 FR at 8755 (March 8, 1990). NOTE: the
guidance set out in the proposed NCP is still effective where not
superseded by guidance or regulations in the final NCP. See 55 FR at
86A6, coi 3
Q4. Should FWQC be used to set drinking-water clean-
up levels for surface water at sites that do not
present environmental concerns?
A. Rarely. FWQC should be used to set drinking-
water cleanup levels only when surface water serves
as an actual or potential drinking-water source and
other cleanup standards for drinking water (e.g.,
non-zero MCLGs, MCLs, or State WQSs designated
for drinking-water use) are not available, (see
Question 5 if impacts to aquatic organisms have also
been identified at the site). Where surface water
serves as an actual or potential drinking-water
source and there are no impacts to aquatic organ-
isms, the following requirements, where relevant and
appropriate, should be attained in the following
order:
State WQSs that are designated for drinking-
water use, and are more stringent than MCLs
or non-zero MCLGs, or specific to the uses of
that water body, or, if none,
Non-zero MCLGs; or, if none,
MCLs; or, if none,
FWQC adjusted for drinking-water use.
Q5. Should FWQC be used to set drinking water clean-
up levels for surface water at sites that do present
environmental concerns?
A. It depends. Generally, non-zero MCLGs or MCLs
should be identified as the ARARs for cleanup of
water that is or may be a potential source of drink-
ing water. However, at sites that also present envi-
ronmental concerns, RPMs should compare the
stringency of the non-zero MCLGs or MCLs to the
pertinent FWQC for aquatic life at the site. If the
FWQC for the aquatic life are more stringent, they
may be the relevant and appropriate requirements
to meet at the site. For example, the levels needed
to pro tea aquatic organisms from volatile organics
are generally much less stringent than the levels
needed to protect human exposure from drinking
water. Therefore, non-zero MCLGs or MCLs would
adequately protect both humans and most aquatic
life from volatile organics. However, the levels
needed to protect aquatic life from metals are more
stringent than those levels required to protect
human exposure from drinking water. As a result,
the FWQC for aquatic organisms would protect
both humans and aquatic life from metals, whereas
non-zero MCLGs or MCLs may not.
-------
Should FWQC be used to set cleanup standards for
ground water?
Rarely. FWQC should be used to set cleanup stan-
dards for ground water only if the ground water is a
current or potential source of drinking water, and
other cleanup standards for drinking water (such as
MCLs and non-zero MCLGs) are not available. If
FWQC are used to set cleanup standards for ground
water, the FWQC should first be adjusted for
drinking-water use (as discussed in Question 7).
Note: the issue becomes more complicated at sites
where the ground water flows into the surface water.
Where the ground water flows naturally into the sur-
face water, the ground-water remediation should be
designed so that the receiving surface-water body will
be able to meet any ambient water-quality standards
(such as State WQSs or FWQC) that may be ARARs
for the surface water. This means that the FWQC
should be considered when establishing cleanup levels
for the ground water at those sites, but they are not
necessarily ARARs for the cleanup of ground water.
At sites where the discharge from a ground-water
treatment facility will be deposited into the surface
water, the discharged water will have to meet all
effluent limitations found in the applicable State
National Pollutant Discharge Elimination System
(NPDES) permits, rather than the FWQC. (The
NPDES effluent limitations will assure compliance
with State WQSs.)
What is required to develop cleanup levels based on
FWQC for human exposure from drinking water
alone?
In those rare circumstances where the FWQC will be
used to establish cleanup levels for drinking water,
RPMs must adjust the original equation used to de-
velop FWQC for human exposure from both inges-
tion of contaminated drinking water and contam-
inated fish. When adjusting the FWQC to develop
cleanup standards for human exposure from drinking
water alone, RPMs should use the standard exposure
assumptions (i.e., 2 liters of water, 6.5 grams of edible
aquatic products, and an average body weight of 70
kg), unless data are available indicating that the
standard exposure assumptions are not pertinent to
the area in which the site is located (see Highlight 1).
Note, however, that adjustment of the FWQC for
drinking is not simply a matter of sub-tracting one
FWQC from another.
While it is possible to derive cleanup levels for
drinking water from FWQC, FWQC were not intend-
ed to be used as drinking-water cleanup standards,
since no criteria are provided for human exposure
from ingestion of water alone. Moreover, the values
derived from the FWQC (in contrast with those de-
rived from MCLs and MCLGs) do not reflect the
contribution of other sources through an appor-
Highlight L: NONCARCINOGENIC EQUATION
For noncarcinogens, acceptable daily intakes
(AD Is) and criteria derived therefrom are
calculated from total exposure data that include
contributions from the diet and air. The equation
used to derive the criterion (C) is:
C = ADI - (DT+IN)/12 liters + (0.0065 kg x R)J
where:
2 liters is assumed daily water consumption;
0,0065 kg is assumed daily fish consumption;
R is bioconcentration factor in units of 1/kg;
DT is estimated non-fish dietary intake; and
IN is estimated daily intake by inhalation.
The equation for carcinogens is not provided
in this fact sheet because FWQC for carcinogens
are recommended at zero, and therefore are not
ARARs for the Superfund program (see Question
#8 of this fact sheet). .
tionment factor. Therefore, FWQC may be less
useful as cleanup standards for potential drinking
water than the MCL/MCLG drinking-water stan-
dards (see proposed NCP preamble, 53 FR at 51442,
and final NCP preamble, 55 FR at 8755).
Q8. How should EPA comply when FWQC for carcino-
gens are determined to be potential ARARs?
A As previously mentioned, the recommended FWQC
for carcinogens are set at zero. Consistent with
Superfund policy on MCLGs, the zero-value FWQC,
since they cannot be measured, would not be consi-
dered appropriate cleanup standards and, thus, are
not "relevant and appropriate requirements" within
the meaning of CERCLA section 121(d)(2)(A) (see
final NCP preamble, 55 FR at 8755). Accordingly,
they are not ARARs and, therefore, they do not
need to be attained or waived.
For the carcinogens, the Office of Water Regula-
tions and Standards (OWRS) has also published for
informational purposes three concentration levels
corresponding to incremental cancer risks of 10'5,
10"6, and 10 , respectively. OWRS has expressly
stated in the preamble to their FWQC publications
that it makes no judgment or recommendation as to
which of the three concentrations provides an
"acceptable" risk level for carcinogens. Instead,
these concentration levels have been provided for
informational purposes only anc, therefore, simply
constitute guidance to-be-consideied (TBCs) for the
Superfund program. As a result, an ARAR waiver
is unnecessary for FWQC published for carcinogens;
-------
Therefore, if these conditions are satisfied, the
antidegradation provision should be met.3
(Note: If pump-and-treat reinjections fail 10 maintain
the current quality of the aquifer, an interim action
waiver could be invoked, assuming the aquifer will be
suitable for its current use upon completion of the
remediation.]
Scenario #2: Natural Attenuation
Assumption: The ground water is contaminated or, at
a minimum, contains a plume of contamination. The
ground water is a Class I or II aquifer (which means
that it is or may be a potential source of drinking
water).
A) State ground-water antidegradation requirements
that prohibit discharges: These are not applicable to
natural attenuation of the ground water because there
is no discharge during natural attenuation.
Compliance: The statute is not applicable to natural
attenuation, but it may be relevant and appropriate
depending upon circumstances at the site (see
Question #5 below).
B) State antidegradation requirements that require
ground-water maintenance consistent with its current
uses: These are potentially applicable to natural
attenuation.
Compliance: The remedy generally would comply
with these requirements during natural attenuation
remediation, if the remedy maintains (i.e., does not
adversely affect) the current quality of the aquifer.
Moreover, it is unlikely that natural attenuation will
interfere with the ground water's current uses, since
natural attenuation is typically confined to sites where
the contaminant level is low, there are small areas of
contamination, and the plume will not migrate signifi-
cantly. Therefore, natural attenuation generally
should meet this type of antidegradation requirement.
[Note: Where such requirements are not met, an
interim action waiver might be appropriate, assuming
the aquifer will be suitable for its current use upon
completion of the remediation.]
3
Here, again, the State may argue that a more limited definition of
"current uses" is the only valid interpretation. If so, consult ORC or OGC.
Scenario #3: Soil Flushing
Assumptions: The soil is contaminated. Through soil
flushing, contaminated effluent will enter the ground
water and then be extracted for treatment The ground
water is a Class I or II aquifer (which means that it t
or may be a potential source of drinking water). The
aquifer may or may not be contaminated.
A) State ground-water antidegradation requirements that
prohibit discharges; These are likely to be applicable
because the effluent from the soil flushing probably
constitutes a discharge. However, the statute is
violated only if the discharge constitutes the type
prohibited by the statute.
Compliance: If, for example, the statute prohibits
discharges injurious to public health, EPA may
conclude that soil flushing would comply with it where
the receiving aquifer is already contaminated. (A
discharge of contaminated effluent into a con-
taminated aquifer generally would not be "injurious to
public health.") Moreover, if pump-and-treat
remediation is conducted concurrently with the soil
flushing, EPA may conclude that the "discharge" is not
injurious to public health because it would be
controlled and contained through the pump-and-treat
remediation.4
(Note: Since it is EPA's goal to restore ground water
to its beneficial uses, the Superfund program would
rarely propose a soil flushing remedy that would
degrade pristine or only slightly contaminated water.
Thus, the issue of compliance of soil flushing with an
antidegradation standard should rarely be a problem
for Superfund ground-water remediations. In rare
cases where degradation of a pristine aquifer through
soil flushing is necessary, RPMs should invoke the
interim measures ARARs waiver.]
B) State antidegradation requirements that require
ground-water maintenance consistent with its current
uses: These presumably are applicable to soil
flushing.
Compliance: The remedy generally would comply with
these requirements during soil flushing, if the remedy
maintains (i.e., does not adversely effect) the current
quality of the aquifer. Current quality of the aquifer
is maintained if the effluent at least meets current
water quality levels of the aquifer. Because soil
flushing is generally only considered for contaminated
aquifers, these requirements typically may be met.5
4
Again, the State may argue that a more limited interpretation is
required. If so, consult ORC or OGC.
5 State arguments that a more restrictive interpretation of the standard
is required should be referred to ORC or OGC
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Highlight L: KEY FACTORS FOR THE
APPLICABILITY OF STATE GROUND-WATER
ANTIDEGRADATION REQUIREMENTS
TO SOIL FLUSHING
Whether the State statute is triggered because
either the effluent constitutes a "discharge" under
the State law, or the State statute requires
ground-water maintenance (during CERCLA
remediation) consistent with current uses;
Whether the statute defines "current uses" as
present uses or pre-contamination uses;
Whether the aquifer is pristine, slightly
contaminated, or greatly contaminated;
Whether the effluent has high contaminant
levels; and,
Whether soil flushing will be conducted
concurrently with pump-and-treat remediation of
the ground water.
Q5. Are State ground-water antidegradation require-
ments likely to be relevant and appropriate re-
quirements for remediation that affects the ground
water?
A. It depends upon whether the requirements are well-
suited for use at the site. While examples are given
below, a more definite answer cannot be given
because relevance and appropriateness is a site-
specific determination. See section 300.400(g)(2) of
the revised NCP. (See the attached matrix for
additional examples.)
For example, State antidegradation requirements that
are applicable to discharges injurious to public health
are potentially relevant and appropriate to all
ground-water remediations (whether or not there is
a discharge), by prohibiting remediations injurious to
public health. These principles, when applied to
CERCLA remediations, should be analyzed as
follows:6
A) EPA does not consider pump-and-treat remediations
of a contaminated plume to be injurious to public
health because they are generally effective at
containing and treating contaminated plumes. (See
OSWER Directive 9355.4-03, October 1989, entitled
"Considerations in Ground-Water Remediation at
Superfund Sites"). Therefore, pump-and-treat
6 The following reflects EPA's general analysis of how several types of
remediation should be evaluated. The State may take a different and more
limited view of what was intended under the statute. If the State argues
for a different interpretation of its laws, consult ORC or OGC.
remediations would generally comply with these
requirements, if relevant and appropriate.
B) Natural attenuation remediation would also be
expected to comply with these requirements
prohibiting injurious discharges (if relevant and
appropriate). Examples include sites where: (1) a
contaminated plume is located within a Class III
aquifer; (2) a contaminated plume is moving within
parts of a Class I or II aquifer that are also signi-
ficantly contaminated; or (3) the plume is small, its
contaminant levels are low, and it will not migrate
significantly. Natural attenuation might be said not
to comply with these requirements if it allows a con-
taminated plume to move into a pristine, or only
slightly contaminated portion of a Class I or II
aquifer; the interim action waiver must be invoked at
such sites, and precautions such as institutional
controls should be taken.
C) Soil flushing generally would comply with these
requirements, if relevant and appropriate, at sites
where the aquifer is already contaminated. Con-
taminants from soil flushing might be said to be
injurious to public health if introduced into a
pristine, or only slightly contaminated portion of a
Class I or II aquifer. In those rare cases where it is
necessary to select this remedy at such sites, the
interim action waiver must be invoked, and
precautions such as institutional controls should be
taken.
Highlight 2: COMPLIANCE WITH STANDARDS
SET BELOW DETECTION LEVELS
State ground-water antidegradation standards that
are set below detection levels cannot be measured or
verified. Therefore, if such standards are applicable,
the technical impracticability waiver should generally
be invoked where compliance with such standards is
not possible due to detection limits. Potentially
relevant and appropriate standards that cannot be
measured or verified may not be appropriate and,
therefore, are not ARARs (see Preamble to the
revised NCP, 55 FR 8750-8752).
Regions should not extrapolate from existing data or
technologies to reach a level set below detection
capabilities because such extrapolations cannot be
verified scientifically with any degree of certainty.
Without verification, neither the Agency nor the
potentially responsible parties could legally establish
that cleanup goals were met. Furthermore, the NCP
states that relevant and appropriate requirements
must be measurable and attainable since their pur-
pose is to set a standard that an actual remedy will
attain (see Preamble to the revised NCP, 55 FR
8752).
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Highlight 3: POTENTIAL ARARs WAIVERS FOR
STATE ANT1DEGRADATION REQUIREMENTS
The Interim Measure Waiver: This waiver provides
that the action selected need not attain an ARAR
where the action "is only part of a total remedial
action that will attain such level or standard of
control when completed," See CERCLA section
121(d)(4)(d). Therefore, the interim measures waiver
may be used to waive ARARs for interim measures
which, by their temporary nature, do not attain all
ARARs. However, the interim measure must be
followed by, or be part of, complete measures that
attain all ARARs, and it should not exacerbate site
problems nor interfere with the final remedy (see the
revised NCP, 55 FR 8747-8748 (March 8, 1990)).
The Inconsistent Application of State Requirements
Waiver: This waiver is intended to prevent the
application to Superfund sites of State requirements
that have not been consistently applied elsewhere in
a State. State standards are presumed to have been
consistently applied unless there is evidence to the
contrary. When questioned by EPA, States may
provide evidence of consistency of application by
demonstrating: (1) the similarity of sites or response
circumstances; (2) the proportion of noncompliance
cases; (3) reasons for noncompliance; and (4)
intentions to apply future requirements (see the
revised NCP, 55 FR 8749 (March 8,1990)).
NOTICE: The policies set out in this ARARs Q's and
A's are intended solely for guidance. They are not
intended, nor can they be relied upon, to create any
rights enforceable by any party in litigation with the
United States. EPA officials may decide to follow the
guidance provided in this Q's and A's, or to act at
variance with the guidance, based on an analysis of
specific site circumstances. The Agency also reserves
the right to change this guidance at any time without
public notice.
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MATRIX ANALYSIS OF STATE GROUND-WATER ANTIDEGRADATION REQUIREMENTS
AS THEY PERTAIN TO CERTAIN REMEDIES AND SITE CIRCUMSTANCES*
REMEDY/SITE CIRCUMSTANCES
STATE LAW
GROUND -WATER RH-5EDIATION:
PUMP AND TREAT
(Aquifer With a Contaminated
Moving Plume)
GROUND-WATER REMEDIATION:
NATURAL ATTENUATION
(Aquifer With a Contaminated
Moving Plume)
SOIL REMEDIATION:
SOIL FLUSHING
(Where the Aquifer May or May
Not Be Contaminated
Followed by Pump and Treat)
SOIL REMEDIATION:
SOIL FLUSHING
(Where the Aquifer May or May
Not Be Contaminated
Concurrent With Pump and Treat)
The ground water
must be protected.
Discharges that are
injurious to public
health are pro-
hibited .
RAR:** ground-water
remediations that
are injurious to
public health are
prohibited. This
may arguably occur
if a remediation
allows a contami-
nated plume to move.
2. The ground water
must be protected.
No discharge is
permitted unless a
State Board issues a
permit.
RAR:*" ground-water
remediations must
protect the ground
water consistent
with State permit
standards (which
may, for example,
prohibit the
introduction of
contaminants into a
portion of an
aquifer used for
drinking).
Not applicable if there is no
discharge If each remjec-
tion is a "discharge," the
requirement is met if the
discharge is not "injurious
to public health" (e.g.,
where the receiving aquifer
is already contaminated, or
if the reinjection has low
contaminant levels). It is
generally not a RAR if the
plume is moving into parts of
the aquifer that are also
significantly contaminated.
If it is a RAR, and it re-
quires some degree of plume
containment, we comply with
it through pump and treat.
Permits are not required (see
CERCLA § 121(e)(1)) Substan-
tive requirements of the per-
mit program are not appli-
cable if there is no dis-
charge If each reinjection
constitutes a "discharge,"
the requirement is met if
each reinjection meets the
substantive requirements of
the permitting regulations
(eg, no "harmful" dis-
charge) It is generally not
a RAR if the plume is moving
to parts of the aquifer that
are also significantly con-
taminated. If it is a RAR,
and it requires some degree
of plume containment, we
comply with it through pump
and treat
Not applicable because there
is no discharge. It is gen-
erally not a RAR if the plume
is moving to parts of the
aquifer that are also signi-
ficantly contaminated. If it
is a RAR, and it requires some
degree of plume containment,
we comply with it by limiting
natural attenuation to sites
where the plume will not mi-
grate to the portions of the
aquifer used for drinking and
contaminant levels are low,
thereby preventing injury to
public health. Otherwise, we
may use the interim action
waiver, usually accompanied by
institutional controls.
Permits are not required (see
CERCLA § 121(e)(1)). Substan-
tive requirements of the per-
mit program are not applicable
because there is no dis-
charge. It is generally not a
RAR if the plume lb moving to
parts of the aquifer that are
also significantly contami-
nated. If it is a RAR, and it
requires some degree of plume
containment, we may comply
with it by limiting natural
attenuation to sites where the
plume will not migrate into
portions of the aquifer desig-
nated for drinking or other
protected uses. Otherwise, we
may use the interim action
waiver, usually accompanied by
institutional controls.
May be a discharge; however,
the requirement is met if the
discharge is not injurious to
public health (e.g., because
the aquifer already exceeds
health-based levels or if the
discharge has low contaminant
levels). If discharging to a
pristine or slightly contam-
inated aquifer, we may use
the interim action waiver.
May be a discharge; however,
no permits are required under
CERCLA 5121(e)(1). If the
substantive requirements of
the permit program are ARARs,
the action may comply if the
contaminant levels of the
effluent entering the ground
water do not exceed the
discharge standards set in
the ROD (based on State
permit requirements). Other-
wise, we may use the interim
action waiver
May be a discharge; however,
the requirement is met if the
discharge is not injurious to
public health (e.g., because
the aquifer already exceeds
health-based levels or if the
discharge has low contaminant
levels). If it is an ARAR, we
may comply with it by conduct-
ing pump and treat simulta-
neously, if the discharge (as
it is part of a contained
treatment system) is not injur-
ious to public health. Other-
wise, we may use the interim
action waiver.
May be a discharge; however, no
permits are required under
CERCLA §121(e)(1). If the
substantive requirements of the
permit program are ARARs, the
action may comply if the
contaminant levels of the
effluent entering the ground
water do not exceed the
discharge standards set m the
ROD (based on State permit
requirements). Otherwise, we
may use the interim action
waiver
- i -
This matrix provides general considerations only. ** Relevant and Appropriate Requirement
nonsuit with ORC or OGC on specific applications.
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MATRIX ANALYSIS OF STATE GROUND-WATER ANTIDEGRADATION REQUIREMENTS
AS THEY PERTAIN TO CERTAIN REMEDIES AND SITE CIRCUMSTANCES*
REMEDY/SITE CIRCUMSTANCES
STATE LAW
GROUND-WATER REMEDIATION:
FUMP AND TREAT
(Aquifer With a Contaminated
Moving Plume)
GROUND-WATER REMEDIATION:
NATURAL ATTENUATION
(Aquifer With a Contaminated
Moving Plume)
SOIL REMEDIATION:
SOIL FLUSHING
(Where the Aquifer May or May
Not Be Contaminated
Followed by Pump and Treat)
SOIL REMEDIATION:
SOIL FLUSHING
(Where the Aquifer May or May
Not Be Contaminated
Concurrent With Pump and Treat)
3. The ground water
must be protected.
No discharge is
permitted to a
usable aquifer.
RAR:** ground-water
remediations that do
not protect a usable
aquifer are pro-
hibited. This may
occur if the remedi-
ation allows a con-
taminated plume to
move.
Requirement is not applicable
if there is no discharge. If
each reinjection constitutes
a "discharge," the require-
ment is not applicable if the
prior contamination already
rendered the aquifer un-
usable. The requirement is
not a RAR if the plume has
rendered the aquifer unusable
or if the plume is moving to
parts of the aquifer that are
also significantly contami-
nated. If it is a RAR, and
it requires some degree of
plume containment, we comply
with it through pump and
treat.
Requirement is not applicable
because there is no discharge.
Also, the requirement is not
applicable if the plume has
rendered the aquifer unusable.
The requirement may not be a
RAR if the plume has rendered
the aquifer unusable or if the
plume is moving to parts of
the aquifer already contami-
nated. If it is a RAR, and it
requires some degree of plume
containment, we may comply
with it by limiting natural
attenuation to sites where the
plume will not migrate to
usable portions of the aqui-
fer. Otherwise, we may use
the interim action waiver,
usually accompanied by insti-
tutional controls.
May be a discharge; however,
the requirement is not appli-
cable if the aquifer is not
usable (e.g., because it is
already contaminated). This
requirement is probably ap-
plicable if the aquifer is
pristine or slightly contam-
inated. If so, we may use
the interim action waiver.
May be a discharge; however,
the requirement is not appli-
cable if the aquifer is not
usable (e.g., because it is al-
ready contaminated). If it is
an ARAR, we may comply with it
by simultaneously conducting
pump and treat if the prompt
containment and treatment of
contaminants protects usable
portions of the aqnifer.
Otherwise, we may use the
interim action waiver.
4. The ground water
must be protected.
No discharge is
permitted if it
interferes with
existing uses.
RAR:"* ground-water
remediations that
interfere with
existing or
potential uses are
prohibited. This
may occur if the
remediation allows a
contaminated plume
to move.
Requirement is not applicable
if there is no discharge. If
each reinjection constitutes
a "discharge, ' the require-
ment is met if the existing
uses (/quality) of the aqui-
fer is maintained (e.g.,
where the aquifer is already
contaminated). It would
generally not be a RAR if the
plume is moving to a portion
of the aquifer that is al-
ready contaminated. If it is
a RAR, and it requires some
degree of plume containment,
we comply with it through
pump and treat.
Requirement is not applicable
because there is no discharge.
It would generally not be a
RAR if the plume is moving to
a portion of the aquifer that
is already contaminated. If
it is a RAR, and it requires
some degree of plume contain-
ment, we may comply with it by
limiting natural attenuation
to sites where contaminant
levels are low and any plume
migration will not affect the
existing uses(/quality) of the
aquifer. Otherwise, we may
use the interim action waiver,
usually accompanied by insti-
tutional controls.
May be a discharge; however,
the requirement is not appli-
cable ;f the existing uses
(/quality) of the aquifer is
maintained (e.g., where the
aquifer is already contami-
nated). This requirement is
probably applicable if the
aquifer is pristine or
slightly contaminated. If so,
we may use the interim action
waiver.
May be a discharge; however,
the requirement is not appli-
cable if the existing uses
(/quality) of the aquifer is
maintained (e.g., where the
aquifer is already contami-
nated). This requirement is
probably applicable if the
aquifer is pristine or slightly
contaminated. If so, we may
use the interim action waiver.
- 2 -
This matrix provides general considerations only. ** Relevant and Appropriate Requirement
*v nor» rvy
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MATRIX ANALYSIS OF STATE GROUND-WATER ANTIDEGRADATION REQUIREMENTS
AS THEY PERTAIN TO CERTAIN REMEDIES AND SITE CIRCUMSTANCES*
REMEDY/SITE CIRCUMSTANCES
STATE LAW
GROUBD-WATER REMEDIATION:
PUMP AND TREAT
(Aquifer With a Contaminated
Moving Plume)
GROUND-WATER REHEDIATIOH:
NATURAL ATTENUATION
(Aquifer With a Contaminated
Moving Flume)
SOIL REMESIATIOH;
SOIL FLUSHING
{Where the Aquifer Hay or May
Hot Be Contaminated
Followed by Pump aaad Treat)
SOIL REMEDIATIOH:
SOIL FLUSHING
(Where the Aquifer May or May
Hot Be Contaminated
Concurrent With Pump and Treat)
5. Maintain ground
water at existing
high quality unless
the State Board
approves the change
to the water qual-
ity. {Statute
requires ground-
water maintenance at
existing high
quality during
remediation. This
may require
containment of a
contaminated moving
plume.}
RAR: same as
applicable.
Requirement is not applicable
if the ground water is not of
high guality due to the con-
taminated plume. This re-
quirement may be applicable
if the aquifer is pristine or
only slightly contaminated.
If so, we may use the interim
action waiver. It may be a
RAR if the plume is moving to
portions of the aquifer that
are designated for drinking
or other protected uses. If
the requirement is a RAR, and
it requires some degree of
plume containment, we comply
with it through pump and
treat.
Requirement is not applicable
if the ground water is not of
high quality due to the con-
taminated plume. If the re-
quirement is a RAR, we may
comply with it by limiting
natural attenuation to sites
where the plume contaminant
levels are low and the plume
will not migrate signifi-
cantly. Otherwise, we may use
the interim action waiver,
usually accompanied by insti-
tutional controls.
Requirement is not applicable
if the ground water is al-
ready contaminated. This re-
quirement may be applicable
if the aquifer is pristine or
only slightly contaminated.
If so, we may use the interim
action waiver.
Requirement is not applicable
if the ground water is already
contaminated. This requirement
may be applicable if the aqui-
fer is pristine or only slight-
ly contaminated. If so, we may
use the interim action waiver
6, Ground-water quality
must be maintained
commensurate with
current uses.
Statute requires
maintenance of
ground-water quaLity
daring remediation,
this may require
contairment of a
contaminated moving
plume.
as
Requirement is presumably
applicable. Requirement is
met if the remedy maintains
the current quality of the
aquifer (e.g., where the re-
injections at least meet
current water uses(/quality)
levels of the aquifer). If
the requirement is an ARAR
and it requires some degree
of plume containment, we
comply with it through pump
and treat
Requirement is presumably
applicable. Requirement is
met if the remedy maintains
the current uses(/quality> of
the aquifer
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