United States Court of Appeals
FOR THE DISTRICT OF COLUMBIA CIRCUIT
Argued February 11, 2000 Decided March 31, 2000
No. 98-1627
Chlorine Chemistry Council and
Chemical Manufacturers Association,
Petitioners
v.
Environmental Protection Agency,
Respondent
Natural Resources Defense Council, et al.,
Intervenors
---------
Consolidated with
99-1053, 99-1056
On Petitions for Review of an Order of the
Environmental Protection Agency
Thomas Richichi argued the cause for petitioners Chlorine
Chemistry Council, et al. and supporting intervenor Society of
the Plastics Industry, Inc. With him on the briefs were
Kathryn Y. Aspegren, David F. Zoll, Katherine L. Rhyne,
Paul D. Clement, Richard S. Wasserstrom, Jerome H. Heck-
man, Peter L. de la Cruz and Komal J. Hershberg.
John F. Cooney and Brock Landry were on the brief for
amicus curiae Public Health Scientists.
Karen L. Egbert, Attorney, U.S. Department of Justice,
argued the cause for respondent. With her on the brief were
Lois J. Schiffer, Assistant Attorney General, and Karen H.
Clark, Attorney, U.S. Environmental Protection Agency.
Christopher S. Vaden, Attorney, U.S. Department of Justice,
entered an appearance.
Alan Charles Raul and David M. Levy were on the brief
for amici curiae Congressman Tom Bliley.
Erik D. Olson was on the brief for intervenors Natural
Resources Defense Council and Physicians for Social Respon-
sibility.
Before: Silberman, Williams and Ginsburg, Circuit
Judges.
Opinion for the Court filed by Circuit Judge Williams.
Williams, Circuit Judge: The Safe Drinking Water Act
("SDWA" or the "Act") directs the Environmental Protection
Agency to set standards for the regulation of covered drink-
ing water contaminants. For each EPA sets a "maximum
contaminant level goal" ("MCLG"), defined as "the level at
which no known or anticipated adverse effects on the health
of persons occur and which allows an adequate margin of
safety." 42 U.S.C. s 300g-1(b)(4)(A). The MCLG is some-
what aspirational. After having set it, EPA is to promulgate
an enforceable standard, known as a maximum contaminant
level ("MCL"), which takes practical considerations into ac-
count while remaining "as close to the [MCLG] as is feasible."
Id. s 300g-1(b)(4)(B).
In March 1998 EPA concluded that chloroform, a drinking
water contaminant, exhibits a "nonlinear mode of carcinogenic
action." Notice of Data Availability: National Primary
Drinking Water Regulations: Disinfectants and Disinfection
Byproducts, 63 Fed. Reg. 15,674, 15,686/1 (1998). In other
words, exposures to chloroform below some threshold level
pose no risk of cancer. But in promulgating the MCLG it
retained the existing standard of zero, which was based on
the previously held assumption that there was no safe thresh-
old. Final Rule: National Primary Drinking Water Regula-
tions: Disinfectants and Disinfection Byproducts, 63 Fed.
Reg. 69,390, 69,398/3 (1998) ("Final Rule"). EPA justified its
action on a variety of grounds, including an alleged need to
consult the report of its Science Advisory Board ("SAB"),
which would not be available until after the statutory deadline
for rulemaking had expired. Petitioners, including the Chlo-
rine Chemistry Council, a trade association comprised of
chlorine and chlorine product manufacturers, petitioned this
court for review, arguing that EPA violated its statutory
mandate to use the "best available" evidence when imple-
menting the provisions of the Safe Drinking Water Act. 42
U.S.C. s 300g-1(b)(3)(A). We agree.
* * *
Chloroform, a "nonflammable, colorless liquid," Proposed
Rule: National Primary Drinking Water Regulations: Disin-
fectants and Disinfection Byproducts, 59 Fed. Reg. 38,668,
38,694/2 (1994), is one of four compounds that together are
classed as "Total Trihalomethanes" ("TTHMs"). These are
byproducts of chlorination, the most widely used technique
for ensuring the safety of drinking water. Chlorination plays
a significant role in the control of microbial pathogens and in
turn in the protection of public health; but on the basis of
rodent tumor data the Agency has concluded that chloroform,
a byproduct of this process, acts as a probable human carcino-
gen. Id. at 38,697/2.
On July 29, 1994 EPA issued a proposed rule on disinfec-
tants and disinfection byproducts in water. This included a
zero MCLG for chloroform, based on EPA's finding of an
absence of data to suggest a threshold level below which there
would be no potential carcinogenic effects. Id. The Agency's
default method of inferring risk at exposure levels for which
it has no adequate data is linear extrapolation from cancer
incidence inferred at exposures for which it does have data.
See EPA's Proposed Guidelines for Carcinogen Risk Assess-
ment, 61 Fed. Reg. 17,960, 17,968/3 (1996). Thus, either if
the evidence supports linearity, or if there is "insufficient"
evidence of nonlinearity, EPA assumes that if a substance
causes cancer at any exposure it will do so at every non-zero
exposure (though with cancer incidence declining with expo-
sure). But EPA acknowledges its authority "to establish
nonzero MCLGs for carcinogens if the scientific evidence"
indicates that a "safe threshold" exists. See Final Rule, 63
Fed. Reg. at 69,401/2. And petitioners here assume the
validity of the linear default assumption.
In 1996 Congress amended the SDWA, enshrining in the
statute a timetable previously set by EPA for rules relating
to disinfectants and disinfection byproducts associated with
water treatment. 42 U.S.C. s 300g-1(b)(2)(C); Proposed
Rule: National Primary Drinking Water Regulations: Moni-
toring Requirements for Public Drinking Water Supplies, 59
Fed. Reg. 6332, 6361 (1994). The relevant deadline here was
November 1998. In preparation for the necessary rulemak-
ing EPA formed an advisory group in 1997 whose purpose
was "to collect, share, and analyze new information and data,
as well as to build consensus on the regulatory implications of
this new information." Notice of Data Availability: National
Primary Drinking Water Regulations: Interim Enhanced
Surface Water Treatment Rule, 62 Fed. Reg. 59,486, 59,491/1
(1997).
On the basis of the committee's findings and recommenda-
tions, EPA in November 1997 published a Notice of Data
Availability ("NODA"), 62 Fed. Reg. 59,388 (1997), and in
1998 it published a second NODA specific to chloroform, 63
Fed. Reg. 15,674 (1998). Among the findings it discussed
were those arrived at by a panel of experts organized by the
International Life Sciences Institute. The panel, whose work
was subject to independent peer review and was convened
under the auspices of the EPA, concluded on the basis of
chloroform's mode of action that although it was "a likely
carcinogen to humans above a certain dose range, [it was]
unlikely to be carcinogenic below a certain dose range." Id.
at 15,685/1. The panel recommended "the nonlinear [ ] or
margin of exposure approach [as] the preferred approach to
quantifying the cancer risk associated with chloroform expo-
sure." Id. at 15,686/1.
EPA agreed. It said that "[a]lthough the precise mecha-
nism of chloroform carcinogenicity is not established," never-
theless "the chloroform dose-response should be considered
nonlinear." Id. at 15,685/3. Rather than operating through
effects on DNA, which is consistent with linearity, chloroform
evidently works through "cytotoxicity" (i.e., damage to the
cells) followed by regenerative cell proliferation. Id. Em-
ploying the threshold approach that it found was entailed by
chloroform's mode of action, EPA then calculated an MCLG
of 600 parts per billion ("ppb"), based solely on carcinogenici-
ty. Id. at 15,686/2. This level built in a 1000-fold margin of
error in relation to the maximum safe dosage implied from
the animal studies used by EPA. Id. But because even
lower chlorine doses cause liver toxicity (a non-cancer effect),
EPA proposed an MCLG of 300 ppb. Id.
When EPA came to promulgate its final rule in December
1998, however, its MCLG was again zero. Final Rule, 63
Fed. Reg. at 69,398/3. It stuck with 1994's zero level despite
its explicit statement that it now "believe[d] that the underly-
ing science for using a nonlinear extrapolation approach to
evaluate the carcinogenic risk from chloroform is well found-
ed." Id. at 69,401/1. It justified the action on the basis that
"additional deliberations with the Agency's SAB on the ana-
lytical approach used" and on the underlying scientific evi-
dence were needed "prior to departing from a long-held EPA
policy." Id. at 69,399-69,401. It could not complete such
additional deliberations by the November 1998 statutory
deadline, and, moreover, the rulemaking would not affect the
enforceable MCL for TTHMs.
After briefing on the petition for review at issue here, but
before oral argument, EPA moved for a voluntary remand to
consider the SAB report on chloroform that would soon be
available. But EPA made no offer to vacate the rule; thus
EPA's proposal would have left petitioners subject to a rule
they claimed was invalid. We denied the motion.
On February 11, 2000, the day of oral argument, EPA
released a draft report by the SAB on chloroform. See
Draft, Chloroform Risk Assessment Review, February 10,
2000 (visited March 27, 2000) . The report concluded that chloro-
form exhibits a "cytotoxic" mode of action. Such a mode of
action (unlike a "genotoxic" mechanism, which acts directly on
a cell's DNA) involves no carcinogenic effects at low doses;
thus a nonlinear approach is "scientifically reasonable." Id.
at 17. After consideration of the draft SAB report, EPA
stated that it "no longer believes that it should continue to
defend its original decision," and moved that this court vacate
the MCLG. Motion for Vacatur, at 2 (February 24, 2000).
* * *
EPA in its motion to vacate concedes that "the discussion
on standing at oral argument indicates that petitioners may
indeed meet minimum requirements for standing," a neces-
sary precursor to our providing any relief beyond the vacatur
proposed by EPA. Given our independent duty to be sure of
our jurisdiction, Floyd v. District of Columbia, 129 F.3d 152,
155 (D.C. Cir. 1997), we address EPA's now evidently aban-
doned jurisdictional arguments.
EPA's brief contends that petitioners lack Article III
standing because they have not demonstrated injury-in-fact
from the MCLG. Lujan v. Defenders of Wildlife, 504 U.S.
555, 560-61 (1992). We have already held, in International
Fabricare Inst. v. EPA, 972 F.2d 384, 390 (D.C. Cir. 1992),
that an association of dry cleaning businesses had standing to
attack EPA's setting of a zero MCLG for a contaminant used
in their business. There we pointed to the MCLG's link to
risks of "greater liability under the Comprehensive Environ-
mental Response, Compensation and Liability Act ('CERC-
LA'), 42 U.S.C. ss 9601-9675," id., which under some circum-
stances may entail remedial action achieving "a level or
standard of control which at least attains Maximum Contami-
nant Level Goals established under the Safe Drinking Water
Act," 42 U.S.C. s 9621(d)(2)(A).
EPA challenges petitioners' theory on several grounds.
First, it says, its regulations provide that when a zero MCLG
is set, it is the MCL, not the MCLG, that is used to set
cleanup standards. 40 CFR s 300.430(e)(2)(i)(C). In this
case, says EPA, the MCL set for TTHMs would control.
Since there is no suggestion that the effective MCL will
imminently be affected by the zero MCLG, and petitioners
have not challenged the MCL for TTHMs, EPA argues that
they have failed to demonstrate an injury.
But the MCL for TTHMs is in fact not dispositive in
setting the cleanup standard for chloroform. EPA has in the
past rejected use of the TTHM MCL for that purpose, saying
that that MCL is "based on an analysis evaluating the health
benefits of chlorinating public drinking water supplies against
the detrimental effects of the production of trihalomethanes
as a result of chlorinating those supplies." U.S. EPA, Super-
fund Record of Decision, Stringfellow Hazardous Waste Site,
at 25 (Sept. 30, 1990). Instead, EPA has set chloroform
cleanup goals as low as 6 ppb (far below the 100 ppb MCL for
TTHMs), based on an assumption that chloroform poses a
risk of cancer at any dose, but that 6 ppb would yield an
acceptable cancer risk of one-in-a-million. Id. Thus EPA's
actual practice belies its claims here as to the inconsequential-
ity of the chloroform MCLG.
EPA also argues that unlike the petitioners in Internation-
al Fabricare, neither petitioners nor their members here have
yet been subjected to cleanup costs for chloroform contamina-
tion, and thus have not demonstrated a "genuine threat" of
CERCLA liability. EPA's Br. at 21. But in a forward-
looking suit the petitioners' subjection to past injury is rele-
vant primarily as it may shed light on whether the challenged
action has a "substantial probability" of causing injury. Flor-
ida Audubon Soc'y v. Bentsen, 94 F.3d 658, 666 (D.C. Cir.
1996) (en banc). CERCLA imposes joint and several liability
on "any person who by contract, agreement, or otherwise
arranged for disposal or treatment ... of hazardous sub-
stances owned or possessed by such person." 42 U.S.C.
s 9607(a)(3). In light of petitioners' contention that they face
liability "for the cleanup of chloroform at Superfund sites
across the country," Petitioners' Reply Br. at 16, we find it at
least substantially probable that a zero MCLG, as compared
with a nonzero one, will expose them to higher cleanup costs.
* * *
Before turning to the merits of petitioners' claim, we note
EPA's contention that its motion to vacate obviates the "need
for the Court to issue an opinion." Motion for Vacatur, at 3.
But we have no reason to believe that mere vacatur provides
an adequate remedy if, as we ultimately conclude, EPA's
action was unlawful. Petitioners request that we instruct
EPA to "promulgate a non-zero MCLG using the best avail-
able peer-reviewed science." Petitioners' Initial Br. at 34.
But EPA has not indicated an intention to take such action
upon vacatur. Moreover, EPA makes no claim that the 1994
zero MCLG would not be automatically revived by vacatur of
the 1998 rule. Our agreement with the petitioners on the
rule's lawfulness will thus bring issues of remedy into play.
On the merits petitioners argue that EPA's decision to
adopt a zero MCLG in the face of scientific evidence estab-
lishing that chloroform is a threshold carcinogen was inconsis-
tent with the Safe Drinking Water Act. Section
300g-1(b)(3)(A) of the Act states unequivocally that "to the
degree that an Agency action is based on science, the Admin-
istrator shall use ... the best available, peer-reviewed science
and supporting studies conducted in accordance with sound
and objective scientific practices." In promulgating a zero
MCLG for chloroform EPA openly overrode the "best avail-
able" scientific evidence, which suggested that chloroform is a
threshold carcinogen.
EPA provides several arguments in defense of its action.
First, it argues that to establish a non-zero MCLG would be a
"precedential step," that represents "a major change in the
substance of regulatory decisions related to chloroform."
EPA's Br. at 28-29. We do not doubt that adopting a
nonzero MCLG is a significant step, one which departs from
previous practice. But this is a change in result, not in
policy. The change in outcome occurs simply as a result of
steadfast application of the relevant rules: first, the statutory
mandate to set MCLGs at "the level at which no known or
anticipated adverse effect on the health of persons occur," 42
U.S.C. s 300g-1(b)(4)(A), as determined on the basis of the
"best available" evidence; and second, EPA's Carcinogen
Risk Assessment guidelines, stating that when "adequate data
on mode of action show that linearity is not the most reason-
able working judgment and provide sufficient evidence to
support a nonlinear mode of action," the default assumption
of linearity drops out. Proposed Guidelines for Carcinogen
Risk Assessment, 61 Fed. Reg. at 17,969/1. The fact that
EPA has arrived at a novel, even politically charged, outcome
is of no significance either for its statutory obligation or for
fulfillment of its adopted policy.
Second, and similarly, EPA supports its action on the basis
that "it could not complete the deliberations with the SAB"
before the November 1998 deadline. EPA's Br. at 29; Final
Rule, 63 Fed. Reg. at 69,399/1. But however desirable it may
be for EPA to consult an SAB and even to revise its conclu-
sion in the future, that is no reason for acting against its own
science findings in the meantime. The statute requires the
agency to take into account the "best available" evidence. 42
U.S.C. s 300g-1(b)(3)(A) (emphasis added). EPA cannot re-
ject the "best available" evidence simply because of the
possibility of contradiction in the future by evidence unavail-
able at the time of action--a possibility that will always be
present.
Third, EPA justifies its decision not to adopt a nonzero
MCLG on the basis that it had to reevaluate one of its
underlying technical assumptions--that ingestion of chloro-
form in drinking water accounts for 80% of total exposure to
chloroform. As it stated in its final rule, EPA is currently
considering use of a 20% relative source contribution for
drinking water, which would lower the MCLG to 70 ppb.
Final Rule, 63 Fed. Reg. at 69,399/3. Along these lines,
EPA's counsel conceded at oral argument that a science-
based MCLG would fall into the interval between 70 and 300
ppb. The uncertainty on this issue may have provided sup-
port for choosing the lowest nonzero MCLG from within that
interval, but none for choosing an MCLG outside the range of
uncertainty.
Fourth, EPA argues that since the final MCL for TTHMs
is unaffected, the MCLG has no actual effect, and thus EPA's
decision to publish an MCLG of zero pending further review
of the scientific evidence was entirely reasonable. In light of
our analysis of the standing issue, the no-effect premise is
plainly incorrect. Even if it were correct, we fail to see why
it would justify EPA's disregard of its own scientific findings.
Finally, EPA argues that its statements in the 1998 Notice
of Data Availability do not represent its "ultimate conclu-
sions" with respect to chloroform, and thus in adopting a zero
MCLG it did not reject what it considered to be the "best
available" evidence. In fact, the zero MCLG merely repre-
sented an "interim risk management decision" pending the
final SAB report. EPA's Br. at 35. We find these semantic
somersaults pointless. First, whether EPA has adopted its
1998 NODA as its "ultimate conclusion" is irrelevant to
whether it represented the "best available" evidence. All
scientific conclusions are subject to some doubt; future, hypo-
thetical findings always have the potential to resolve the
doubt (the new resolution itself being subject, of course, to
falsification by later findings). What is significant is Con-
gress's requirement that the action be taken on the basis of
the best available evidence at the time of the rulemaking.
The word "available" would be senseless if construed to mean
"expected to be available at some future date." Second, EPA
cannot avoid this result by dubbing its action "interim." The
statute applies broadly to any "[a]gency action"; whether the
action is interim is irrelevant.
* * *
Although we agree with petitioners that the zero MCLG for
chloroform is inconsistent with the Safe Drinking Water Act
and that it should be vacated, we are unclear as to what
further remedy petitioners seek. In their opening brief
petitioners requested that this Court instruct EPA to "pro-
mulgate a non-zero MCLG using the best available peer-
reviewed science as identified in the March 31, 1998 NODA
and the December 16, 1998 Final Rule on an expeditious
timetable to be specified by the Court." Petitioners' Initial
Br. at 34. At oral argument, however, counsel for petitioners
conceded that this request was a misstatement, and that EPA
should be allowed, and required, to consider the new SAB
report as well. Further, the consequences of simple vacatur
are themselves unclear. Accordingly, we will schedule brief-
ing on the parties' positions as to remedy.
Finding the Agency's December 1998 rule adopting a zero
MCLG for chloroform to be arbitrary and capricious and in
excess of statutory authority, see 5 U.S.C. s 706(2)(A) & (C),
we vacate the rule. A separate order on briefing additional
remedies will issue shortly.
So ordered.