&EPA
United States
Environmental Protection
Agency
Office of
Solid Waste and
Emergency Response
Publication 9234.2-09/FS
June 1990
ARARs Q's & A's:
Compliance With Federal Water
Quality Criteria
Office of Emergency and Remedial Response
Office of Program Management OS-240
Quick Reference Fact Sheet
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.
Ql. 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.
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
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 F^ 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."
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
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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 marinnim contaminant level goals (MCLGs),
maximum rantnminant 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.)
See proposed NCP preamble, S3 FR 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 F£ at
8666, col. 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 protect 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
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Q6. Should FWQC be used to set cleanup standards for
ground water?
A. 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.)
Q7. What is required to develop cleanup levels based on
FWQC for human exposure from drinking water
alone?
A. In those rare circumstances where the FWQC will be
used to establish cleanup levels for drinking water,
RPMs must adjust the nridnai 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 (Le., 2 liters of water, &5 grains 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-
Hlghlight L: NONCARCINOGENIC EQUATION
For noncarcinogens, acceptable daily intakes
(ADIs) 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)/[2 liters + (0.0065 kg x R)]
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 dietaiy 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 s,
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 and, therefore, simply
constitute guidance to-be-considered (TBCs) for the
Superfund program. As a result, an ARAR waiver
is unnecessary for FWQC published for carcinogens;
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because FWQC recommended at zero are not
ARARs, the three alternative values are TBCs.
Q9. What other factors should be considered in
determining whether FWQC are relevant and
appropriate requirements?
A. CERCLA requires that in determining whether a
FWQC constitutes a relevant and appropriate
requirement, EPA must consider the designated or
potential use of the surface or ground water, the
environmental media affected, the purposes for which
such criteria were developed, and the latest available
scientific information available (see CERCLA section
121(d)(2)(B)(i». With regard to this last factor,
OWRS periodically publishes FWQC for additional
constituents and occasionally updates existing ones.
Prior to using an FWQC for a particular constituent,
RPMs should consult the IRIS data base maintained
by the EPA Office of Research and Development and
contact their Regional Water Office for the most
recent listing, to ensure consideration of the latest
available scientific information. See Attachment 1
for a list of the FWQC, current as of June 15,1990.
[Note: the FWQC chart issued by the EPA Office
of Water Regulations and Standards, dated January
2,1987, is no longer current and should not be used
as a reference.]
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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ATTACHMENT 1
FEDERAL WATER QUALITY CRITERIA
(#> COMPOUND
CAS
Nuiber
FRESHWATER
Criterion Criterion
Max 1rui Continuous
Cone. Cone.
(ug/L)
-------
A
(1)
COMPOUND
CAS
Nuaber
45
2-Chlorophenol
95578
46
2.4-0ichlorophenol
120832
47
2.4-Oinethylphenol
105679
48
2-Methy1-4.6-0initrophenol
534521
49
2.4-0initrophenol
51285
50
2-Nitrophenol
88755
51
4-Nitrophenol
100027
52
3-Methyl-4-Chlorophenol
59607
53
Pentachlorophenol
87865
54
Phenol
108952
55
2.4.6-Trichlorophenol
88062
56
Acenaphthene
83329
57
Acenaphthylene
208968
58
Anthracene
120127
59
Benzidine
92875
60
Benzo(a)Anthracene
56553
61
Benzo(a)Pyrene
50328
62
3.4-Benzofluoranthene
205992
63
Benzo(ghi)Perylene
191242
64
Benzo()t)Fluoranthene
207089
65
Bis(2-Chloroethoxy)Nethane
111911
66
Bis<2-Chloroethyl)8ther
111444
67
Bis(2-Chloroisopropyl)Ether
108601
68
Bis(2-EthylheKyl)Phthalate
117817
69
4-Broaophenyl Phenyl Ether
101553
70
Butylbenzyl Phthalate
85687
71
2-Chloronaphthalem
91587
72
4-Chlorophenyl Phenyl Ether
7006723
73
Chrysene
218019
74
Oibenz(a.h)Anthracene
53703
75
1.2-Dichlorobenzene
95501
76
1.3-Oichlorobenzene
541731
77
1.4-Oichlorobenze*
106*67
78
3.3'-Oichlorobenzidiae
91941
79
Diethyl Phthalate
84662
80
Diaethyl Phthalate
131113
81
Oi-n-Butyl Phthalate
84742
82
2.4-0initrotoluene
121142
83
2.6-0initrotoluene
«nft2H2
84
Di-n-Octyl Phthalate
117840
85
1.2-Diphenylhydrazine
122667
86
Fluoranthene
206440
87
Fluorene
86737
88
Hexachlorobenzene
118741
89
Hexachlorobutadiene
87683
freshwater
Criterion Criterion
Maxima Continuous
Cone. Cone.
(ug/L) (ug/L)
B1 B2
SALTWATER
Criterion Criterion
Maxima Continuous
Cone. Cone.
(ug/L) (uq/L)
CI C2
HUMAN HEALTH
(10"* risk for carcinogens)
For Consuaption of:
Water & Organists
Organisas Only
(ug/L) (ug/L)
PI D2
120 *
93 * 790
13.4
765
70 *
14000 ~
1000 *
29000 *
21
4600 '
1.2 t
3.6 t
1200 *
2700
0.0028 t
0.0311 t
0.0028 t
0.0311 t
0.00012
0.00054 »t
0.0028 t
0.0311 t
0.0028 t
0.0311 t
0.0028 t
0.0311 t
0.0028 t
0.0311 t
0.0028 t
0.0311 t
0.031 *t
1.4 *t
1400
170000 »
1.8 *t
5.9 *t
3000 *
5200 *
0.0028 t
0.0311 t
0.0028 t
0.0311 t
2700 *
17000 *
400
2600
400
2600
0.04 *t
0.077 *t
23000
120000 *
313000
2900000
2700
12000 *
0.11 t
9.1 t
0.041 *t
0.54 *t
42
54
0.0028 t
0.031 t
0.00072 t
0.00074 t
0.44 *t
50
-------
A
B
C
D
--
t R 8 S H
HATER
SALTWATER
HUNAN B
B A L T H
(lO"4 risk for carcinoqens)
Criterion
Criterion
Criterion
Criterion
For Consumption of:
Maxima
Continuous
Naxiaui
Continuous
Hater &
Organises
(»>
CONPOUNO
CAS
Cone.
Cone.
Cone.
Cone.
Organists
Only
Nunber
(uq/L)
(ug/L)
(uq/L)
< uq/L)
(uq/L)
(uq/L)
B1
B2
CI
C2
01
02
90
Hexachlorocyclopentadiene
77474
242 *
17400 *
91
Hexachloroethane
67721
2.0 *t
8.9 *t
92
IndenoO .2.3-cd)Pyrene
193395
0.0028 t
0.0311 t
93
Isophorone
78591
6900 *
490000 *
94
Naphthalene
91203
95
Nitrobenzene
98953
17
1900 *
96
N-Nitrosodinethylaiine
62759
0.00069
8.1 *t
97
N- Ml t rosod i -n-Propy] aii ne
621647
0.005 »t
8.5 »t
98
N-Nitrosodiphenylatine
86306
5.0 *t
16 *t
99
Phenanthrene
85018
0.0028 t
0.0311 t
100
Pyrene
129000
0.0028 t
0.0311 t
101
1.2.4-Trichlorobenzene
120821
102
Aldrin
309002
3 X
1.3 t
0.00013 *t
0.00014 *t
103
alpha-BBC
319846
0.0039 *t
0.013 *t
104
beta-BBC
319857
0.014 »t
0.046 *t
105
qnu-BE
58899
2 t
0.08 X
0.16 X
0.019 t
0.063 t
106
delta-BBC
319868
107
Chlordane
57749
2.4 1
0.0043 X
0.09 X
0.004 X
0.00058 *t
0.00059 *t
108
4-4-D0T
50293
1.1 X
0.001 $
0.13 1
0.001 X
0.00059 »t
0.00059 *t
109
4.4-OOB
72559
0.00069 «t
0.00059 *t
110
4.4-OOD
72548
0.00083 *t
0.00083 #t
111
Oieldrin
60571
2.5 X
0.0019 X
0.71 *
0.0019 X
0.00014 *t
0.00014 *t
112
alpha-Endosulfan
959988
0.22 X
0.056 t
0.034 X
0.0087 X
0.93 *
2.0
113
beta-Endosulfan
33213659
0.22 X
0.056 X
0.034 X
0.0087 t
0.93
2.0 *
114
Endoeulfan Sulfate
1031078
0.93
2.0 »
115
Endrin
72208
0.18 X
0.0023 X
0.037 X
0.0023 X
0.76
0.81
116
Endrin Aldehyde
7421934
0.52 X
0.0036 X
0.76 *
0.81
117
Eeptachlor
76448
0.0038 X
0.053 X
0.00021 *t
0.00021
118
Heptachlor Epoxide
1024573
0.52 X
0.0038 X
0.053 X
0.0036 X
0.00010 »t
0.00011 »t
119
PCB-1242
1336363
0.014 X
0.03 X
0.000044 *t
0.000045 *t
120
PCB-1254
11097691
0.014 t
0.03 X
0.000044 *t
0.000045 *t
121
PCB-1221
11104282
0.014 X
0.03 X
0.000044 *t
0.000045 *t
122
PCB-1232
11141165
0.014 t
0.03 X
0.000044 *t
0.000045 «t
123
PCB-1248
12672296
0.014 X
0.03 X
0.000044 *t
0.000045 »t
124
PCB-1260
11096825
0.014 X
0.03 X
0.000044 *t
0.000045 *t
125
PCB-1016
12674112
0.014 X
0.03 X
0.000044 *t
0.000045 *t
126
Toxaphene
8001352
0.73
0.0002
0.21
0.0002
0.00073 »t
0.00075 *t
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~ Criteria revised to reflect current agency qt* or RfD, as contained in the Integrated Risk Inforaation System (IRIS).
** Freshwater aquatic life criteria for these netals are expressed as a [unction of total hardness («j/l), as follows
(where exp represents the base e exponential function). (Values displayed above correspond to a total hardness of
100 ag/l.)
CMC exp(B,lln(hardness) I ~ b4) CCC exp(«,lln(hardness) I * b^l
e, b. Xe be
Cadaiui
1.128
-3.828
0.7852
-3.490
Copper
0.9422
-1.464
0.8545
-1.465
Chroaiua (III)
0.8190
3.688
0.8190
1.561
Lead
1.273
-1.460
1.273
-4.705
Nickel
0.8460
3.3612
0.8460
1.1645
Silver
1.72
-6.52
Zinc
0.8473
0.8604
0.8473
0.7614
Freshwater aquatic life criteria for pentachlorophenol are expressed as a function of pH. and are calculated as
follows. (Values displayed above correspond to a pB of 7.8.)
CMC - expd.OOS(pB) - 4.830) CCC - exp(1.005
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