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United States Court of Appeals

FOR THE DISTRICT OF COLUMBIA CIRCUIT

Argued November 20, 2002 Decided February 25, 2003

No. 01-1028

CITY OF WAUKESHA, ET AL.,

PETITIONERS

v.

ENVIRONMENTAL PROTECTION AGENCY,

RESPONDENT

VILLAGE OF SUSSEX WATER COMMISSION, ET AL.,

INTERVENORS

No. 01-1033

RADIATION, SCIENCE & HEALTH, INC.,

PETITIONER

v.

ENVIRONMENTAL PROTECTION AGENCY,

RESPONDENT

–————

 Bills of costs must be filed within 14 days after entry of judgment.

The court looks with disfavor upon motions to file bills of costs out

of time.
2

No. 01-1034

NUCLEAR ENERGY INSTITUTE, INC.,

PETITIONER

v.

ENVIRONMENTAL PROTECTION AGENCY,

RESPONDENT

No. 01-1037

NATIONAL MINING ASSOCIATION,

PETITIONER

v.

ENVIRONMENTAL PROTECTION AGENCY,

RESPONDENT

On Petitions for Review of an Order of the

Environmental Protection Agency

John C. Martin, Michael B. Wigmore, Curt R. Meitz, and

David C. Lashway argued the cause for the petitioners.

John N. Hanson, Brian L. Doster, Justin A. Savage, Jean V.

MacHarg, Susan M. Mathiascheck, Donald P. Gallo, H.

Stanley Riffle, Phillip J. Eckert, Paul F. Reilly, John S.

Noble, Richard M. Glidden, Anthony J. Thompson, Robert

W. Bishop, James B. Harvey, Suzanne K. Schalig, William

Von Arx, and Dennis M. Duffy were on brief.

Daniel M. Flores and Christopher Peak, Attorneys, United

States Department of Justice, argued the cause for the
3

respondent. Karen Clark, Attorney, United States Environmental Protection Agency, was on brief.

Before: HENDERSON, ROGERS, and GARLAND, Circuit Judges.

Opinion for the court filed PER CURIAM.

PER CURIAM: The petitioners—the City of Waukesha and

its water utility customer Bruce Zivney, trade associations

Nuclear Energy Institute (‘‘NEI’’) and National Mining Association (‘‘NMA’’), and advocacy group Radiation, Science &

Health (‘‘RSH’’)—seek review of regulations promulgated by

the Environmental Protection Agency (‘‘EPA’’) pursuant to

the Safe Drinking Water Act of 1970 (‘‘SDWA’’ or ‘‘Act’’), 42

U.S.C. §§ 300f et seq. The challenged regulations establish

standards governing radionuclide levels in public water systems. Specifically, they set the maximum contaminant level

goal (‘‘MCLG’’) and the maximum contaminant level (‘‘MCL’’)

for radium-226 and radium-228, naturally occurring uranium,

and various beta/photon emitters. Petitioners contend the

regulations violate the SDWA and the Administrative Procedure Act, 5 U.S.C. §§ 551 et seq., (‘‘APA’’) because in setting

the radionuclides standards EPA did not (1) properly conduct

required cost-benefit analyses; (2) use the ‘‘best available

science’’ to determine the appropriate MCLGs and MCLs; or

(3) adequately respond to comments submitted during the

rulemaking. For its part, EPA contests petitioners’ standing

to challenge the regulations and defends the standards on the

merits. We conclude that all petitioners except RSH have

standing and that EPA complied with the requirements of the

SDWA and the APA.

I. BACKGROUND

The SDWA generally applies to ‘‘each public water system

in each State,’’ 42 U.S.C. § 300g, and authorizes EPA to set

standards for drinking water contaminants therein, 42 U.S.C.

§ 300g-1(b). For a given contaminant the Act directs that

EPA first establish an MCLG which is ‘‘the level at which no

known or anticipated adverse effects on the health of persons
4

occur and which allows an adequate margin of safety.’’ Id.

§ 300g-1(b)(4)(A). EPA is then to set an MCL ‘‘as close to

the [MCLG] as is feasible.’’ Id. § 300g-1(b)(4)(B).

In 1976 EPA promulgated interim regulations that established MCLGs and MCLs for radionuclides, which are materials that emit radiation as they decay from one elemental form

to another. The regulations established an MCL of 5 picocuries/Liter (pCi/L)1

 for the isotopes radium-226 and radium228; a combined MCL of 4 millirems (mrem)2

 for all

beta/photon emitters; and no MCL for naturally-occurring

uranium. See National Interim Primary Drinking Water

Regulations, 41 Fed. Reg. 28,402, 28,404 (July 9, 1976).

In 1991 EPA proposed new MCLs for the radionuclides: 20

pCi/L for radium-226 and -228; 4 mrem effective dose equivalent (‘‘ede’’) for the beta/photon emitters;3

 and 20 micrograms

per liter (mg/L) or 30 pCi/L for naturally occurring uranium.

See National Primary Drinking Water Regulations; Radionuclides, Notice of Proposed Rulemaking, 56 Fed. Reg. 33,050,

33,051 (July 18, 1991).

1 The curie measures the rate at which a given radioactive

compound disintegrates. One curie is equivalent to 3.7 x 1010

disintegrations per second. A picocurie is a millionth millionth of a

curie. National Primary Drinking Water Regulations; Radionuclides, Advance Notice of Proposed Rulemaking, 51 Fed. Reg.

34,836, 34,850 (Sept. 30, 1986).

2 The rem measures the dose of radiation an individual receives

from a certain type of exposure. EPA, Radionuclides Notice of

Availability, Technical Support Document at I-5 (March 2000). A

rem takes into account not only the number of radioactive emissions

that are present (i.e., the curies) but also the energy of the radiation

and the types of particles that are emitted. 51 Fed. Reg. at 34,849–

50.

3 The effective dose equivalent measures the amount of radiation

distributed to an individual. The radiation amount is first estimated for each individual organ and the result is adjusted by a

‘‘weighting factor’’ to reflect the radiosensitivity of the particular

organ. The sum of the ede of each organ provides an estimate of

the total effect on the entire body. 51 Fed. Reg. at 34,843.
5

In 1996 the Congress amended the SDWA to, inter alia,

add an ‘‘anti-backsliding’’ provision requiring that any water

regulation revision ‘‘maintain, or provide for greater, protection of the health of persons,’’ 42 U.S.C. § 300g-1(b)(9), and to

require the agency to consider the relative costs and benefits

in setting each MCL, id. § 300g-1(b)(3)(C), (4)(C).

In April 2000 EPA issued a ‘‘Notice of Data Availability’’

(‘‘NODA’’) proposing that the 1991 radionuclide MCLs be

revisited in light of ‘‘new information’’ and the 1996 amendments. National Primary Drinking Water Regulations; Radionuclides, 65 Fed. Reg. 21,576 (Apr. 21, 2000).4

 The 2000

NODA proposed maintaining the 1976 MCLs for radium-226

and -228 and for beta/photon emitters and set MCLs for

naturally occurring uranium at either 20, 40, or 80 mg/L.

EPA further proposed revising the 1976 radium monitoring

regimen—which required public water systems to test for

radium-228 only if the radium-226 level exceeded 3 pCi/L—to

require separate testing for each of the two isotopes. The

NODA further set June 20, 2000 as the deadline for submitting comments on the proposed rule and its underlying data

and analysis.

In December 2000 EPA issued the final radionuclides rule,

National Primary Drinking Water Regulations; Radionuclides, 65 Fed. Reg. 76,708 (Dec. 7, 2000) (Final Rule). As it

had proposed, EPA retained the 1976 standards for radium226 and -228 and for beta/photon emitters and instituted the

separate radium isotope monitoring requirement. Id. at

76,710–11. For uranium, however, the final rule set the MCL

at 30 mg/L. Id. at 76,710. Petitioners filed timely petitions

for review of the final rule.

Petitioners bring several challenges to the 2000 final rule.

First, they argue that EPA failed to publish a cost-benefit

analysis for the radium and beta/photon MCLs as required by

SDWA § 1412(b)(3)(C)(i), and that the agency’s cost-benefit

analysis of the uranium MCL fell short of the requirements of

4 EPA agreed to review and take final action on the radionuclides

standards by November 21, 2000 in a consent agreement it executed

with a private litigant. 65 Fed. Reg. at 21,579.
6

the SDWA and the APA. We discuss those arguments in

Parts III and IV, respectively. Petitioners also attack the

radium, uranium, and beta/photon MCLs on their merits, and

we consider those challenges in Parts V, VI, and VII, respectively. Finally, petitioners assert that EPA, in violation of

the APA, failed adequately to respond to comments in promulgating the 2000 final rule. We discuss that assertion in

Part VIII. EPA defends against each of petitioners’ arguments on the merits, and in turn, contests petitioners’ standing to bring their petitions, an argument to which we now

turn.

II. STANDING

First, we address the threshold issue of our jurisdiction,

specifically, whether petitioners have standing to raise their

claims. Sierra Club v. EPA, 292 F.3d 895, 898 (D.C. Cir.

2002). In analyzing whether a party has standing, the court

must determine whether there is ‘‘(1) injury-in-fact, (2) causation, and (3) redressability.’’ Id. In alleging an injury-infact, petitioners must show that ‘‘EPA’s alleged failings have

caused a traceable ‘concrete and particularized’ harm TTT that

is ‘actual or imminent.’ ’’ Id. (quoting Am. Petroleum Inst. v.

United States Envtl. Prot. Agency, 216 F.3d 50, 63 (D.C. Cir.

2000)). To establish this, petitioners ‘‘must demonstrate that

there is a ‘substantial probability’ that local conditions will be

adversely affected.’’ Id. In addition, in evaluating the standing of an association to sue on behalf of its members, the

court must determine that

(1) at least one of [the association’s] members would

have standing to sue in his own right, (2) the interests

the association seeks to protect are germane to its purpose, and (3) neither the claim asserted nor the relief

requested requires that an individual member of the

association participate in the lawsuit.

Id.

The burden of making these showings rests on the petitioner in an agency review case. Id. at 899. ‘‘In such cases TTT

the petitioner ordinarily will have participated in the proceed-
7

ings before the agency,’’ and therefore the administrative

record will establish the relevant facts for the petitioner to

show standing. Id. The petitioner must ‘‘either identify in

that record evidence sufficient to support its standing to seek

review or TTT submit additional evidence to the court of

appeals,’’ id., although additional evidence is unnecessary if

its ‘‘standing to seek review of administrative action is selfevident,’’ id. at 899–900. In explaining how petitioners should

satisfy that burden, Sierra Club, decided June 18, 2002,

announced that ‘‘henceforth’’ petitioners must include in their

opening briefs sufficient evidence to demonstrate their standing. Id. at 900. ‘‘Absent good cause shown, TTT a litigant

should not expect the court’’ to allow petitioners to submit

affidavits post-oral argument in order to support their standing arguments. Id. Because the opening briefs in this case

were filed before our decision in Sierra Club, and EPA has

not objected to the filing of supplemental affidavits, our

resolution of the question of standing is based on the submissions in petitioners’ opening briefs as well as on the supplemental affidavits submitted, with the permission of the court,

after oral argument. See, e.g., United States Telecom Ass’n

v. FCC, 295 F.3d 1326, 1330 (D.C. Cir. 2002).

A.

The administrative record shows that the City of Waukesha

would face substantial costs if it was required to comply with

the 1976 radium-226 and -228 regulations. EPA has not

disputed that record evidence. This is sufficient for injury-infact. Moreover, Waukesha has shown, and EPA does not

dispute, that maintenance of the 1976 regulations will cause

Waukesha’s injury. EPA contends, however, that, to the

extent that Waukesha and the other utility petitioners base

their challenge on EPA’s failure to properly conduct a costbenefit analysis, there is no standing because there is no

redressability. In particular, EPA maintains that even if it

did not properly develop cost-benefit analyses for the radium

regulations, it could not have used those analyses to raise the

numerical limits, because the SDWA prohibits the use of costbenefit analyses to weaken standards in place at the time of
8

the 1996 amendments to the SDWA. Waukesha responds

that the court could order the agency to properly follow the

relevant procedural requirements, and it alleges that EPA’s

failures to follow those requirements are the injuries that it

has suffered.

A violation of the procedural requirements of a statute is

sufficient to grant a plaintiff standing to sue, so long as the

procedural requirement was ‘‘designed to protect some

threatened concrete interest’’ of the plaintiff. Lujan v. Defenders of Wildlife, 504 U.S. 555, 573 n.8 (1992). As explained in Florida Audubon Society v. Bentsen, 94 F.3d 658,

665 (D.C. Cir. 1996), a plaintiff must show ‘‘not only that the

defendant’s acts omitted some procedural requirement, but

also that it is substantially probable that the procedural

breach will cause the essential injury to the plaintiff’s own

interest.’’ There are ‘‘at least two links’’ in an ‘‘adequate

causal chain’’ between a procedural violation and injury-infact, ‘‘one connecting the omitted [procedure] to some substantive government decision that may have been wrongly

decided because of the lack of [the procedure] and one

connecting that substantive decision to the plaintiff’s particularized injury.’’ Id. at 668. The second link requires a

showing that ‘‘the particularized injury that the plaintiff is

suffering or is likely to suffer is fairly traceable to the agency

action that implicated’’ the procedural requirement in question. Id. at 669.

Here, the procedural requirements for a cost-benefit analysis are related to the threatened interest of Waukesha. The

cost-benefit analysis would examine whether the drinking

water regulations are overly costly compared to the health

benefits they would provide, resulting in increased and unjustified costs for water suppliers. See 42 U.S.C. § 300g1(b)(3)(C), (b)(6)(A). Moreover, the harm suffered by Waukesha—increased water treatment costs—is fairly traceable to

the substantive action of EPA that is challenged by petitioners—the maintenance of the 1976 radium regulations. EPA

challenges the first causal link connecting the procedural

requirement—the cost-benefit analysis—and the substantive

actions of EPA. EPA essentially contends that there is no

chance that performing the cost-benefit analysis, as requested
9

by Waukesha, will alleviate the harm suffered by Waukesha,

namely, overly strict water-quality standards.5

 Although

some sort of connection between the procedural requirement

at issue and the substantive action of the agency must be

shown, see Fla. Audobon, 94 F.3d at 668, the Supreme Court

has held that this requirement is not very stringent.

Thus, under our case law, one living adjacent to the site

for proposed construction of a federally licensed dam has

standing to challenge the licensing agency’s failure to

prepare an environmental impact statement, even though

he cannot establish with any certainty that the statement

will cause the license to be withheld or altered.

Lujan, 504 U.S. at 572 n.7. In fact, ‘‘[a]ll that is necessary is

to show that the procedural step was connected to the

substantive result.’’ Sugar Cane Growers Coop. of Fla. v.

Veneman, 289 F.3d 89, 94–95 (D.C. Cir. 2002); see also Fla.

Audubon, 94 F.3d at 669. Indeed, in reviewing the standing

question, the court must be careful not to decide the questions on the merits for or against the plaintiff, and must

therefore assume that on the merits the plaintiffs would be

successful in their claims. Warth v. Seldin, 422 U.S. 490, 502

(1975); Am. Fed’n of Gov’t Employees v. Pierce, 697 F.2d

303, 305 (D.C. Cir. 1982). Consequently, because we assume

that Waukesha is correct when it contends that the SDWA

does not prohibit the Secretary from raising the relevant

standards based on a cost-benefit analysis, there is some

connection between the procedural right (the cost-benefit

analysis) and the substantive decision (the decision not to

relax the drinking water standards). Thus, EPA’s redressability argument fails.

5 In their reply brief, petitioners argue that they were also

harmed by the failure to conduct a cost-benefit analysis because of

the lack of ‘‘consistent, predictable’’ clean-up standards. Petitioners’ Reply Br. at 5. Nothing in the attached affidavit or in the brief

itself shows how a failure to perform the cost-benefit analysis will

harm petitioners other than the possibility of setting stricter standards than otherwise might have been imposed.
10

Having concluded that the City of Waukesha has standing

to challenge the radium regulations, it is unnecessary for the

court to evaluate standing for Bruce Zivney or any of the

remaining utilities who are parties to this case. See Envtl.

Action v. FERC, 996 F.2d 401, 406 (D.C. Cir. 1993).

B.

NEI contends that it has standing to challenge the

beta/photon emitter standard because ‘‘[i]ts members’ facilities are potential sources of beta/photon radionuclides,’’ which

are also ‘‘potentially subject to the beta/photon MCLs at

decommissioned facilities under CERCLA [Comprehensive

Environmental Response, Compensation and Liability Act, 42

U.S.C. §§ 9601–9675].’’ Petitioners’ Br. at 12. EPA maintains that NEI has failed to demonstrate standing because

NEI has only stated that its members may be ‘‘potentially’’

subject to the MCLs, which does not meet the requirement

that injury-in-fact be concrete and particularized. Respondent’s Br. at 27.

With its reply brief, NEI submitted an affidavit stating that

EPA ‘‘will impose CERCLA requirements (including the

SDWA MCLs) at those [NEI member] sites where groundwater is a current or potential drinking water source.’’ Petitioners’ Reply Br. Tab A at 2. NEI further avers in the

affidavit that decommissioned nuclear industry sites have

residual radioactive material that ‘‘typically consists of a

mixture of different radionuclides’’ that will be covered by the

beta/photon MCL. Id. at 4. The affidavit concludes that

‘‘application by EPA of the 2000 SDWA beta/photon MCL

will in some cases result in increases to NEI members’

regulatory compliance costs.’’ Id.

To the extent that the demonstration of standing requires

substantial specificity and particularity on the part of plaintiffs seeking to establish injury-in-fact, see, e.g., Am. Petroleum Inst., 216 F.3d at 63–68, it is arguable that NEI’s initial

affidavit falls short. ‘‘Bare allegations are insufficient TTT to

establish a petitioner’s standing to seek judicial review of

administrative action.’’ Sierra Club, 292 F.3d at 898. Fur-
11

ther, plaintiffs must show a ‘‘substantial probability’’ that the

agency action will cause the alleged injury-in-fact, Am. Petroleum Inst., 216 F.3d at 63–68, and plaintiffs must also show

that ‘‘local conditions will be adversely affected,’’ Sierra Club,

292 F.3d at 898. At no point in its initial affidavit does NEI

state that any particular site owned by any of its members

had radionuclides that might be covered by the rule, nor does

it ever state that a particular site would be decommissioned

and therefore become subject to CERCLA. Further, NEI’s

claims as to future coverage by CERCLA are hedged with

qualifiers such as ‘‘typically’’ and ‘‘in some cases.’’ Petitioners’ Reply Br. Tab A at 4. NEI never states that there is a

substantial probability that EPA would require a particular

site to be cleaned-up to the SDWA MCL standards for

beta/photon emitters.

A supplemental affidavit provided after oral argument,

however, reveals that at least one of NEI’s members owns a

nuclear power plant that has begun the process of decommissioning, and that plant also has identified at least one

beta/photon emitter that is present at levels higher than the

MCL at issue. At oral argument, EPA conceded that its

current regulations and enforcement policy would result in

the application of the beta/photon emitter MCL to decommissioned nuclear power plants. As a result, that particular

plant faces a substantial probability of higher site investigation and remediation costs under CERCLA as a result of the

beta/photon emitter MCL at the present time. Whether, as

EPA suggested at oral argument, EPA chooses to change the

regulations in the future so that MCLs would no longer apply

to decommissioned nuclear power plants under CERCLA, or

so that the MCLs are altered significantly, presents only a

speculative possibility that does not eliminate the current

circumstances faced by the NEI-member plant that is undergoing decomissioning. Thus, at least one member of NEI has

shown injury-in-fact caused by the application of the

beta/photon SDWA MCL to CERCLA clean-up standards.

See Chlorine Chemistry Council v. EPA, 206 F.3d 1286,

1289–90 (D.C. Cir. 2000). And, as noted, NEI has shown that
12

its injury could be redressed either through a new costbenefit analysis, or overturning of the regulations on their

merits.

The remaining associational requirements are easily fulfilled by NEI: NEI seeks injunctive relief, which does not

require the participation of particular individuals, Hunt v.

Wash. State Apple Adver. Comm’n, 432 U.S. 333, 344 (1977),

and the goals of the lawsuit are germane to NEI’s overall

purpose of advancing the interests of the nuclear power

industry, Nat’l Lime Ass’n v. EPA, 233 F.3d 625, 636–37

(D.C. Cir. 2000). Because NEI has standing to challenge the

beta/photon emitter provisions, it is unnecessary for the court

to address the standing of any other party with respect to the

beta/photon emitter provisions.

C.

NMA challenges both the uranium and radium-226 and -228

regulations. NMA’s initial showing of its standing was set

forth in a conclusory statement in the administrative record

that it may be harmed by the proposed regulations:

The proposed [regulations] for radionuclides (specifically

uranium and radium-226 and -228) may impact NMA

member companies to the extent they provide water

supply services to communities associated with mining

and mineral processing facilities. In addition, NMA

member companies also may be impacted by the application of [the regulations] as limits on groundwater at

mining and mineral processing facilities under other

‘‘contamination’’ regulatory programs.

Letter from Nat’l Mining Ass’n to EPA (June 20, 2000). The

statement does not identify any NMA members that own or

operate particular water supply services that would be affected by the proposed rule or that own particular sites that

might be covered by other ‘‘ ‘contamination’ regulatory programs,’’ and states only that the proposed regulations ‘‘may

impact’’ its members. See Sierra Club, 292 F.3d at 900.

NMA’s supplemental affidavits filed after oral argument cure

any deficiency, however, by identifying an NMA member that
13

operates a community water system subject to regulation

under the SDWA, and by averring that there is a substantial

probability that this water system will have uranium levels

above the MCL provided for by EPA’s new regulations,

resulting in significant monitoring, compliance, and disposal

costs for that member. This is sufficient to demonstrate

injury-in-fact and causation on the part of NMA. The injunctive relief sought by NMA would redress these harms.

Because NMA, like NEI, has shown that at least one of its

members has standing to sue, because NMA seeks injunctive

relief such that the participation of individual members in the

litigation is not required, and because the purpose of the

litigation is related to NMA’s overall goals of promoting the

interests of the mining industry, we conclude that NMA has

standing to pursue the challenge to the uranium standards.

D.

RSH, much like NEI and NMA, did not make an initial

showing that it has standing. Rather it relied on its comments in the administrative record that do not establish that

any of RSH’s members have suffered any type of injury from

the proposed regulations. While stating in its brief that ‘‘its

members would be injured based on the likelihood of increased drinking water costs resulting from this regulation,’’

Petitioners’ Reply Br. at 5, RSH, unlike NEI and NMA, has

provided no affidavit that establishes with specificity and

concreteness any particular member of RSH that is likely to

suffer increased drinking water costs. Thus, RSH does not

have standing to challenge the proposed regulations.

To the extent that RSH seeks to challenge EPA’s responses to comments attacking EPA’s reliance on the linear nonthreshold model, we note that the City of Waukesha and

NMA also raise this challenge. Because the linear nonthreshold model is relevant to the setting of the MCLG and

MCL for all of the contaminants, the City of Waukesha and

NMA have standing to raise this claim.
14

III. THE APPLICABILITY OF THE COST-BENEFIT

REQUIREMENTS TO THE RADIUM AND

BETA/PHOTON MCLs

Petitioners attack EPA’s final radium and beta/photon

MCLs on the ground that § 1412(b)(3)(C)(i) of the SDWA, 42

U.S.C. § 300g-1(b)(3)(C)(i), allegedly required EPA to conduct a cost-benefit analysis for each MCL, which EPA failed

to do.6

 EPA responds that no cost-benefit analysis was

6 Section 1412(b)(3)(C)(i) provides, in relevant part:

When proposing any national primary drinking water regulation that includes a maximum contaminant level, the Administrator shall, with respect to a maximum contaminant level that

is being considered in accordance with paragraph (4) and each

alternative maximum contaminant level that is being considered pursuant to paragraph (5) or (6)(A), publish, seek public

comment on, and use for the purposes of paragraphs (4), (5),

and (6) an analysis of each of the following:

(I) Quantifiable and nonquantifiable health risk reduction

benefits for which there is a factual basis in the rulemaking

record to conclude that such benefits are likely to occur as

the result of treatment to comply with each level.

(II) Quantifiable and nonquantifiable health risk reduction

benefits for which there is a factual basis in the rulemaking

record to conclude that such benefits are likely to occur from

reductions in co-occurring contaminants that may be attributed solely to compliance with the maximum contaminant

level, excluding benefits resulting from compliance with other

proposed or promulgated regulations.

(III) Quantifiable and nonquantifiable costs for which there

is a factual basis in the rulemaking record to conclude that

such costs are likely to occur solely as a result of compliance

with the maximum contaminant level, including monitoring,

treatment, and other costs and excluding costs resulting from

compliance with other proposed or promulgated regulationsTTTT

42 U.S.C. § 300g-1(b)(3)(C)(i)(I)–(III).
15

required for these MCLs because the SDWA exempts pre1986 MCLs from its cost-benefit requirements, and the agency left the pre-existing MCLs for radium and beta/photon

emitters unchanged. Unless ‘‘Congress has directly spoken

to the precise question at issue,’’ we must uphold the agency’s

interpretation of the SDWA as long as it is ‘‘based on a

permissible construction of the statute.’’ Chevron U.S.A. Inc.

v. Natural Res. Def. Council, 467 U.S. 837, 842–43 (1984).7

In 1996, Congress amended § 1412 of the SDWA. See

Safe Drinking Water Act Amendments of 1996, Pub. L. No.

104-182, 110 Stat. 1613. As amended, § 1412(b)(3)(C)(i) provides that, ‘‘[w]hen proposing any national primary drinking

water regulation that includes a maximum contaminant level,’’

EPA must publish and seek public comment on an analysis of

the health risk reduction benefits and costs associated with

the proposed MCL. 42 U.S.C. § 300g-1(b)(3)(C)(i). EPA is

to use that analysis ‘‘for the purposes of paragraph[ ] (4),’’

subparagraph (C) of which states:

At the time the Administrator proposes a national primary drinking water regulation under this paragraph,

the Administrator shall publish a determination as to

whether the benefits of the maximum contaminant level

justify, or do not justify, the costs based on the analysis

conducted under paragraph (3)(C).

Id. § 300g-1(b)(4)(C). However, amended § 1412(a)(1) also

includes a grandfather clause:

Effective on June 19, 1986, each national interim or

revised primary drinking water regulation promulgated

under this section before June 19, 1986, shall be deemed

to be a national primary drinking water regulation under

subsection (b) of this section. No such regulation shall

be required to comply with the standards set forth in

7 All parties agree that Chevron governs our review of EPA’s

interpretation of the statute, see Petitioners’ Br. at 13; Respondent’s Br. at 34, an interpretation that was developed in the NODA,

see 65 Fed. Reg. at 21,579, and in the notice of the final rule, see id.

at 76,737.
16

subsection (b)(4) of this section unless such regulation is

amended to establish a different maximum contaminant

level after June 19, 1986.

Id. § 300g-1(a)(1) (emphasis added).

EPA argues that § 1412(a)(1) exempts the radium and

beta/photon MCLs from the cost-benefit determination required by § 1412(b)(4)(C), because they do not establish

different contaminant levels from those first promulgated in

1976. EPA further reasons that because the purpose of the

cost-benefit analysis required by § 1412(b)(3)(C)(i) is to inform the cost-benefit determination required by § (b)(4)(C),

and because that determination is not required for the preexisting MCLs, no cost-benefit analysis was required for

those MCLs. In Part III.A we consider petitioners’ attack on

EPA’s view that cost-benefit analyses are not required when

the agency decides to retain pre-existing MCLs. In Part

III.B we consider petitioners’ claim that EPA did not in fact

retain the pre-existing MCLs for radium and beta/photon

radionuclides, but instead issued new standards.

A.

Petitioners raise three challenges to EPA’s view that costbenefit analyses are not required when it retains pre-1986

MCLs.

First, petitioners contend that the declaration of

§ 1412(a)(1)’s grandfather clause, that pre-existing MCLs are

not ‘‘required to comply with the standards set forth in

subsection (b)(4) of this section,’’ 42 U.S.C. § 300g-1(a)(1)

(emphasis added), is not a reference to § (b)(4)(C)’s costbenefit determination requirement because that requirement

is not a ‘‘standard.’’ Rather, petitioners contend that the only

‘‘standards’’ in § (b)(4) are those in § (b)(4)(A) and (B), which

apply to ‘‘maximum contaminant level goals’’ and ‘‘maximum

contaminant levels,’’ respectively. Id. § 300g-1(b)(4)(A), (B).8

8 These subsections provide, in relevant part:

(A) Maximum contaminant level goals
17

EPA, however, correctly counters that the term ‘‘standards’’

is ambiguous; indeed, the term serves as the title for all of

§ 1412(b), and ‘‘[g]oals and standards’’ is the title for all of

§ (b)(4). There is nothing unreasonable about the agency’s

view that whether the benefits of an MCL justify its costs

qualifies as a ‘‘standard’’ by which the MCL may be measured.

Second, petitioners contend that even if the grandfather

clause does apply to the cost-benefit determination requirement of § 1412(b)(4), it does not expressly apply to the costbenefit analysis requirement of § (b)(3)(C)(i). Although the

observation is correct, the agency is justified in describing

this as an instance where ‘‘the statute is silent TTT with

respect to the specific issue,’’ and hence where judicial deference to the agency’s interpretation is warranted. Chevron,

467 U.S. at 842. Because the statute provides that the

§ (b)(3)(C)(i) analysis is to be ‘‘used for the purposes of

paragraph[ ] (4),’’ 42 U.S.C. § 300g-1(b)(3)(C)(i),9

 it is reasonEach maximum contaminant level goal established under this

subsection shall be set at the level at which no known or

anticipated adverse effects on the health of persons occur and

which allows an adequate margin of safety.

(B) Maximum contaminant levels

Except as provided in paragraphs (5) and (6), each national

primary drinking water regulation for a contaminant for which

a maximum contaminant level goal is established under this

subsection shall specify a maximum contaminant level for such

contaminant which is as close to the maximum contaminant

level goal as is feasible.

42 U.S.C. § 300g-1(b)(4)(A), (B).

9 In full, this sentence of § 1412(b)(3)(C)(i) states that the costbenefit analysis is to be used ‘‘for the purposes of paragraphs (4),

(5), and (6).’’ 42 U.S.C. § 300g-1(b)(3)(C)(i); see supra note 6.

Neither paragraph (b)(5) nor (b)(6) is applicable here, as both are

exceptions to the requirements of paragraph (b)(4), from which preexisting MCLs are exempt by virtue of the grandfather clause.
18

able for the agency to regard such an analysis as unnecessary

in situations in which a § (b)(4) determination will not be

made.

Third, petitioners argue that, because EPA could not have

known when it published its 2000 proposal to retain the preexisting MCLs that it would ultimately decide to keep them,

the grandfather clause of § 1412(a)(1) did not exempt the

agency from conducting a cost-benefit analysis at that time.

But since § (a)(1) states that ‘‘no’’ pre-existing regulation is

required to comply with the standards of § (b)(4) ‘‘unless

such regulation is amended,’’ id. § 300g-1(a)(1) (emphasis

added), it is reasonable for the agency to conclude that the

cost-benefit requirement is not triggered by a proposal to do

nothing more than retain, unamended, pre-existing MCLs.

Petitioners stress that § 1412(b)(3)(C)(i) states that the agency is to produce a cost-benefit analysis ‘‘[w]hen proposing

any’’ MCL. Id. § 300g-1(b)(3)(C)(i) (emphasis added). But

EPA correctly notes that the rest of the sentence provides

that the analysis is to be produced only ‘‘with respect to a

[MCL] that is being considered in accordance with paragraph

(4) and each alternative [MCL] that is being considered

pursuant to paragraph (5) or (6).’’ Id.; see supra note 6.

Due to the grandfather clause, none of the MCLs at issue

here were being ‘‘considered in accordance with paragraph

(4).’’ Nor were they being considered ‘‘pursuant to paragraph (5) or (6).’’ See supra note 9.

EPA bolsters its position on all of these points by reference

to another statutory provision, § 1412(b)(9), which it aptly

Paragraph (b)(5) authorizes EPA to establish an MCL at a level

other than the feasible level required under paragraph (b)(4) if the

‘‘means used to determine the feasible level would result in an

increase in the health risk from drinking water’’ for specified

reasons. 42 U.S.C. § 300g-1(b)(5)(A). Paragraph (b)(6) permits

the agency to promulgate an MCL that is not as close to the MCLG

as is feasible if EPA determines that the benefits of the feasible

level would not justify the costs of compliance. Id. § 300g1(b)(6)(A).
19

refers to as the SDWA’s ‘‘anti-backsliding’’ provision. That

section states:

The Administrator shall, not less often than every 6

years, review and revise, as appropriate, each national

primary drinking water regulation promulgated under

this subchapter. Any revision of a national primary

drinking water regulation shall be promulgated in accordance with this section, except that each revision

shall maintain, or provide for greater, protection of the

health of persons.

42 U.S.C. § 300g-1(b)(9) (emphasis added). EPA notes that

§ (b)(9) bars it from revising an MCL unless the revision at

least maintains the existing MCL’s level of health protection,

and reasonably concludes that this means the agency may not

raise an existing MCL on the basis of a cost-benefit analysis

alone. That conclusion is supported by the legislative history,

which states: ‘‘Section 1412(b)(9) precludes the use of this

new cost-benefit standard-setting authority as the sole basis

to relax any existing maximum contaminant level.’’ S. Rep.

No. 104-169, at 35 (1995). Accordingly, where the agency

proposes to retain an existing MCL, and where (as here)

there is no evidence that raising the MCL would provide

equivalent health protection, a cost-benefit analysis would

have no consequence and the agency is justified in concluding

that Congress did not intend to require it to undertake such a

futile exercise.

For the foregoing reasons, we conclude that EPA’s reading

of the SDWA as not requiring the production of a cost-benefit

analysis when the agency decides to retain pre-1986 MCLs is

a reasonable statutory interpretation to which this court is

obligated to defer.10

10 Petitioners further contend that, because EPA ‘‘repromulgated’’ the existing rules only after public comment and reevaluation,

those rules are subject to challenge as though they were new, citing

Public Citizen v. NRC, 901 F.2d 147, 150 (D.C. Cir. 1990). Because

this argument was raised for the first time in petitioners’ reply

brief, we decline to entertain it. See, e.g., McBride v. Merrell Dow

& Pharm., Inc., 800 F.2d 1208, 1210–11 (D.C. Cir. 1986) (‘‘We
20

B.

Petitioners next contend that even if the SDWA exempts

EPA from producing a cost-benefit analysis when it leaves in

place pre-existing MCLs, the 2000 beta/photon and radium

MCLs are in fact different from the 1976 standards and

hence not subject to § 1412(a)(1)’s exemption. We disagree.

With respect to beta/photon emitters, petitioners note that

improved scientific methods have led EPA to conclude that

the 1976 MCLs generally ensure greater health protection

(and less risk) than the agency had originally anticipated.

From this fact, petitioners assert that, by retaining the 1976

MCLs, the agency ‘‘effectively issue[d] a different standard

than the one issued in 1976.’’ Petitioners’ Reply Br. at 14.

This assertion is unjustified. As we have discussed, EPA

reasonably interprets § (a)(1) to exempt a pre-1986 regulation

from the statute’s cost-benefit determination provision ‘‘unless such regulation is amended to establish a different maximum contaminant level after June 19, 1986.’’ 42 U.S.C.

§ 300g-1(a)(1). Because the SDWA defines ‘‘maximum contaminant level’’ as ‘‘the maximum permissible level of a

contaminant in water which is delivered to any user of a

public water system,’’ id. § 300f(3) (emphasis added), EPA is

right to focus on the level of contaminant set by the original

MCL rather than the degree of protection that such a level

was anticipated to provide. Since EPA’s 2000 beta/photon

MCLs neither ‘‘amended’’ the 1976 MCLs nor ‘‘establish[ed]

TTT different maximum contaminant level[s],’’ id. § 300g1(a)(1), the exemption of § (a)(1) is plainly applicable.

Nor does petitioners’ argument weaken the support that

the anti-backsliding provision gives to EPA’s conclusion that

the 2000 beta/photon MCLs are exempt from the cost-benefit

requirements. As we have discussed, § 1412(b)(9) provides

generally will not entertain arguments omitted from an appellant’s

opening brief and raised initially in his reply briefTTTT Considering

an argument advanced for the first time in a reply brief TTT is not

only unfair to an appellee, but also entails the risk of an improvident or ill-advised opinion on the legal issues tendered.’’ (citations

omitted)).
21

that any revision of an MCL ‘‘shall maintain, or provide for

greater, protection of the health of persons.’’ Id. § 300g1(b)(9). Petitioners contend that this provision does not

prohibit EPA from revising an MCL upward when (as here)

scientific advances show that a contaminant poses less risk

than previously believed, and that in those circumstances the

agency may consider a cost-benefit analysis in determining

whether to raise the MCL. This argument requires inferring

the following bracketed and italicized qualification to the

actual language of § (b)(9): ‘‘[E]ach revision shall maintain,

or provide for greater, protection of the health of persons

[than the agency initially thought it was providing].’’ Id.

But there is nothing unreasonable about EPA’s decision to

decline to read such a qualification into the section, and

instead to regard it as a straightforward instruction to maintain the level of protection that the initial MCL actually

provides.

11

With respect to the radium MCL, petitioners argue that

the 2000 radium standard is new because, although it retains

the same 5 pCi/L level as the original MCL, it requires

separate radium-228 monitoring regardless of the concentration of radium-226. See 65 Fed. Reg. at 76,712, 76,719. The

original regulation required radium-228 monitoring only if the

level of radium-226 exceeded 3 pCi/L. See 41 Fed. Reg. at

28,404. As discussed above, the agency reasonably interprets

§ 1412(a)(1) to provide an exemption from cost-benefit requirements for a pre-existing regulation unless EPA chooses

to establish a different maximum contaminant level. In this

case the maximum contaminant level has remained the same,

and we agree with EPA that the fact that the agency has

changed its monitoring technique, thereby tightening enforce11 In further support of their argument, petitioners cite the

following statement in the legislative history: ‘‘If new science shows

that a less stringent standard would provide the same level of

health protection, the MCL may be revised upward.’’ S. Rep. No.

104-169, at 33 n.4. But this citation adds nothing to their case.

Just as above, to carry petitioners’ meaning, the phrase ‘‘that the

agency initially thought it was providing’’ would still have to be

inserted before the comma in the cited statement.
22

ment of compliance with the original level, does not take the

2000 radium regulation out of the statutory exemption. Accordingly, EPA was not required to produce a cost-benefit

analysis with respect to the 2000 MCLs for either radium or

beta/photon radionuclides.12

IV. THE ADEQUACY OF THE COST-BENEFIT

ANALYSES PERFORMED FOR THE

URANIUM MCL

By contrast to the 2000 radium and beta/photon regulations, the uranium MCL issued in that year represented a

‘‘new’’ standard, as there was no pre-existing MCL for uranium. See 65 Fed. Reg. at 76,708. Section 1412(b)(3)(C)(i)

therefore required EPA to prepare and publish a cost-benefit

analysis, and it did so. Petitioners contend that EPA’s

analysis failed to satisfy the requirements of that section and

the APA.

A.

Petitioners’ first argument is that EPA failed to comply

with § (b)(3)(C)(i) because it did not analyze the costs and

benefits associated with compliance with the uranium MCL in

contexts other than the SDWA.13 In particular, petitioners

12 Given this conclusion, it is unnecessary for the court to consider

arguments relating to the specific costs and benefits that petitioners

contend EPA failed to consider with respect to the radium rule.

13 Petitioners also argue that EPA failed to comply because it did

not consider disposal costs for waste-stream residuals from the

operation of uranium water-treatment systems, or health risks that

those residuals pose to water-treatment workers and the general

public. The record reflects that EPA did adequately consider those

issues. See Office of Ground Water and Drinking Water, EPA,

Economic Analysis of the Radionuclides National Primary Drinking Water Regulations 4-3 (2000) (explaining that ‘‘total treatment

costs include the capital and operations and maintenance costs

associated with residuals handling and disposal’’); Office of Ground

Water and Drinking Water & Office of Radiation and Indoor Air,

EPA, Preliminary Health Risk Reduction and Cost Analysis 4-4
23

assert that EPA failed to evaluate the costs and benefits

arising from compliance with the MCLs at hazardous waste

sites governed by CERCLA. EPA counters that the SDWA

does not require it to analyze such costs.

EPA again has the better of the argument. Section

(b)(3)(C)(i)(III) requires EPA to analyze:

Quantifiable and nonquantifiable costs for which there is

a factual basis in the rulemaking record to conclude that

such costs are likely to occur solely as a result of

compliance with the maximum contaminant level, including monitoring, treatment, and other costs and excluding costs resulting from compliance with other proposed or promulgated regulations.

42 U.S.C. § 300g-1(b)(3)(C)(i)(III) (emphasis added). EPA

reasonably reads the italicized words, particularly the phrase

‘‘excluding costs resulting from compliance with other TTT

regulations,’’ as excluding costs associated with compliance

with regulatory regimes other than the SDWA itself. As

EPA argues, the purpose of the MCLs is to protect the

public, as much as feasible, from the adverse health effects of

drinking contaminated water. See id. § 300g-1(b)(4)(A), (B).

That purpose would be undermined if the cost-benefit balance

were skewed by consideration of the additional costs imposed

by other uses of the MCLs, unrelated to protecting consumers of drinking water.

Petitioners attack EPA’s view on a number of grounds.

First, they note that the cited exclusion refers only to costs

resulting from compliance with other ‘‘regulations.’’

CERCLA, they correctly point out, is not a regulation but a

(2000) (hereinafter ‘‘PHRRCA’’) (same); see also EPA, CommentResponse Document 20-4 to 20-5, 20-7 to 20-21 (2000) (response to

comments 20.A.4, 20.B.1 to 20.B.22) (noting that the risks that

waste-treatment residuals pose to water-treatment workers and the

public were analyzed in draft guidelines issued in 1994) (hereinafter

‘‘Comment-Response Document’’); Office of Ground Water and

Drinking Water, EPA, Draft Suggested Guidelines for Disposal of

Drinking Water Treatment Wastes Containing Radioactivity

(1994).
24

statute—one that specifically instructs that the clean-up of

hazardous waste sites must satisfy contamination standards

promulgated under the SDWA. See 42 U.S.C.

§ 9621(d)(2)(A). But EPA, equally correctly, points out that

like most statutes, CERCLA’s mandate is implemented by

regulations, which, among other things, set forth the circumstances under which MCLGs and MCLs of the SDWA are to

be used as clean-up standards, as well as the circumstances

under which compliance with them can be waived. See 40

C.F.R. § 300.430(e), (f); see generally 40 C.F.R. pt. 300.

Moreover, as EPA further notes, CERCLA itself imposes no

requirement that EPA consider the costs and benefits of

compliance with MCLs as an element of clean-up standards,

and certainly no requirement that the agency do so as part of

its obligations under a separate statute like the SDWA.

Second, petitioners contend that the legislative history of

the SDWA indicates that the exclusion of consideration of the

costs of compliance with other regulations applies only to

those regulations that are themselves the product of costbenefit analysis. This argument relies on a single sentence

from a Senate report: ‘‘[T]he Administrator is not to consider

the benefits (or costs) that are attributable to compliance with

other proposed or promulgated regulations, if those benefits

and costs are considered in a determination as to whether

benefits justify costs under those regulations.’’ S. Rep. No.

104-169, at 29–30. But as EPA notes, while this passage

mandates that the agency may not consider benefits and

costs under such circumstances, it does not state that the

agency must do so under all other circumstances. Since the

statute itself contains no such qualification on its exclusion of

the consideration of the costs and benefits of other regulations, that is hardly an unreasonable view for the agency to

take.

Third, petitioners assert that even if the SDWA does

exclude consideration of the costs associated with the application of MCLs in other contexts, the Act does not also exclude

consideration of the benefits of applying MCLs under other

regulatory regimes. In support, petitioners point to the

benefits provision of § 1412(b)(3)(C)(i)(I), which, unlike the
25

costs provision of § (b)(3)(C)(i)(III), contains no exclusion

relating to compliance with other regulations. See supra note

6. Without qualification, the benefits provision requires an

analysis of ‘‘[q]uantifiable and nonquantifiable health risk

reduction benefits TTT likely to occur as the result of treatment to comply with each level.’’ 42 U.S.C. § 300g1(b)(3)(C)(i)(I). But while it is true that § (b)(3)(C)(i)(I)

contains no exclusion, in context it is also clear that the

section’s use of the phrase ‘‘the result of treatment’’ refers to

drinking water treatment, and not to treatment of contaminants for other purposes. See id. § 300g-1(b)(3)(C)(ii); id.

§ 300g-4(e)(3). Moreover, we do not understand what petitioners hope to gain by requiring EPA to add further to the

benefits (but not to the costs) of MCLs in conducting its costbenefit analysis; such a calculus would only increase the

justification for the MCLs actually promulgated by EPA, as

compared to the higher levels favored by petitioners.

Finally, petitioners contend that EPA has itself ‘‘acknowledged the necessity of evaluating benefits and costs of MCLs

at CERCLA sites.’’ Petitioners’ Br. at 26. It is true that

EPA’s preliminary cost-benefit analysis stated that ‘‘the impact of the regulations on other programs, such as the use of

MCLs in site clean-up decisions,’’ was a ‘‘factor[ ] TTT of

interest to decision-makers and will be taken into account in

the final selection of the regulatory options to be implemented.’’ PHRRCA, at 6-8. But regarding something as a factor

‘‘of interest’’ is not the same as regarding it as a statutory

obligation, and nothing else in the agency’s statements suggests that EPA has regarded the consideration of CERCLA

costs and benefits as mandatory.

For the foregoing reasons, we reject petitioners’ contention

that EPA’s cost-benefit analysis failed to analyze costs and

benefits as required by § 1412(b)(3)(C)(i).

B.

In conducting the cost-benefit analysis for the uranium

regulations, EPA published both an initial cost-benefit analysis, issued before the NODA, and a final cost-benefit analysis,
26

issued about a month before the final regulations were published in the Federal Register. The initial cost-benefit analysis, for which EPA requested comments, provided discussion

of the 20, 40, and 80 mg/L standards. The final cost-benefit

analysis also included a discussion for the 30 mg/L standard

that EPA ultimately promulgated; that discussion was based

in large part on an interpolation by EPA from the analyses

for the other proposed levels.

Petitioners contend that (1) EPA failed to comply with the

SDWA’s requirement that a cost-benefit analysis be performed for the 30 mg/L uranium standard that EPA implemented in the final rule, and (2) EPA failed to comply with

the APA with respect to both the cost-benefit analysis and

the issuance of the 30 mg/L rule. EPA responds that it did

not violate the SDWA provisions or the APA because it

‘‘provided ample opportunity for public comment on the uranium MCL, conducting a cost-benefit analysis for several

possible uranium MCLs in the range of 20 to 80 mg/L.’’

Respondent’s Br. at 43. According to EPA, its final 30 mg/L

rule was a ‘‘logical outgrowth’’ of the proposed rule, such that

the notice and opportunity to comment on the original three

proposed MCLs incorporated the final 30 mg/L rule. Id.

Petitioners reply that the ‘‘logical outgrowth’’ test is inapplicable because the plain language of the SDWA requires that

EPA ‘‘shall, with respect to TTT each alternative maximum

contaminant level that is being considered TTT, publish, seek

public comment on, and use for the purposes of paragraphs

(4), (5), and (6) an analysis’’ of the costs and benefits of that

alternative. 42 U.S.C. § 300g-1(b)(3)(C)(i) (emphasis added);

Petitioners’ Reply Br. at 9-10.

The traditional APA ‘‘logical outgrowth’’ test applies where

an agency changes its final regulation in some way from the

proposed regulation for which it provided notice and requested comment, as required under the APA. As this court has

recognized:

EPA undoubtedly has authority to promulgate a final

rule that differs in some particulars from its proposed

rule. As we noted in International Harvester Co. v.

Ruckelshaus, 478 F.2d 615, 632 n.51 (D.C. Cir. 1973), ‘‘[a]
27

contrary rule would lead to the absurdity that TTT the

agency can learn from the comments on its proposals

only at the peril of starting a new procedural round of

commentary.’’ However, if the final rule deviates too

sharply from the proposal, affected parties will be deprived of notice and an opportunity to respond to the

proposal.

Courts have devised various verbal formulas for the

extent to which an agency can make changes in the final

rule that were not clearly presaged by the notice of

proposed rulemaking. This court has held, both under the

APA and under Clean Air Act § 307(d), that the final

rule must be a ‘‘logical outgrowth’’ of the proposed rule.

Small Refiner Lead Phase-Down Task Force v. United States

Envtl. Prot. Agency, 705 F.2d 506, 546–47 (D.C. Cir. 1983)

(alterations in original). Under the ‘‘logical outgrowth’’ test,

then, the key question is whether commenters ‘‘should have

anticipated’’ that EPA might use a 30 mg/L standard when it

first provided notice of its proposals. Id. at 549.

Contrary to petitioners’ position, the fact that the SDWA

establishes a somewhat different notice-and-comment format

for new regulations than the standard APA procedures does

not necessarily mean that the ‘‘logical outgrowth’’ test is

inapplicable. Under other statutes that have altered the

notice-and-comment format for rulemaking, such as the Clean

Air Act, the court has held that the ‘‘logical outgrowth’’ test is

applicable. See, e.g., Husqvarna AB v. EPA, 254 F.3d 195,

203 (D.C. Cir. 2001). Further, strictly applying the plain

language of the SDWA, as petitioners advocate, would lead to

the absurd results that the doctrine is intended to avoid in the

first place. Without a ‘‘logical outgrowth’’ test, EPA would

be prevented from issuing a final MCL of 20.1 mg/L, even

where it had conducted a cost-benefit analysis for 20 mg/L

and EPA had decided that a slight shift in the MCL would be

advantageous. Indeed, petitioners conceded at oral argument

that their position would have required EPA to conduct an

entirely new cost-benefit analysis in order for it to adopt the

MCLs that petitioners themselves had suggested to EPA in

their comments.
28

Turning then to consider whether the ‘‘logical outgrowth’’

test was satisfied by EPA, we bear in mind that the doctrine

must be considered in the context of this specific statute,

where its applicability may be somewhat stricter than in the

generic APA case. Cf. Nat’l Constructors Ass’n v. Marshal,

581 F.2d 960, 970-71 & n.27 (D.C. Cir. 1978). As noted, in

making that determination the court must consider ‘‘whether

the party, ex ante, should have anticipated’’ the changes to be

made in the course of the rulemaking. Ariz. Pub. Serv. Co. v.

EPA, 211 F.3d 1280, 1299 (D.C. Cir. 2000) (quotation omitted). Thus, one factor is ‘‘whether a new round of notice and

comment would provide the first opportunity for interested

parties to offer comments that could persuade the agency to

modify its rule.’’ Id. (emphasis in original) (quotation omitted). At oral argument, petitioners conceded that there were

no additional comments or evidence they could have proffered

for the record during the administrative proceedings as to

how the costs and benefits would have differed for an MCL at

30 mg/L as opposed to 20 mg/L or 40 mg/L. Aside from a

cursory statement that interpolation does not constitute the

required ‘‘best available methods,’’ 42 U.S.C. § 300g1(b)(3)(A)(ii), for the cost-benefit analysis, petitioners have

not suggested any criticism they would have raised concerning EPA’s method of interpolation of the data.

Of course, the failure of an interested party to show how

their comments would have been different had adequate

notice been provided does not necessarily preclude a successful claim of inadequate notice-and-comment or a lack of a

‘‘logical outgrowth’’ connection between the proposed and

final rule. The APA requires petitioners to show prejudice

from an agency procedural violation. See 5 U.S.C. § 706. In

making such a showing in the context of a violation of noticeand-comment requirements, petitioners may be required to

demonstrate that, had proper notice been provided, they

would have submitted additional, different comments that

could have invalidated the rationale for the revised rule. See

Shell Oil Co. v. EPA, 950 F.2d 741, 752 (D.C. Cir. 1991)

(citing Air Transport Ass’n of Am. v. CAB, 732 F.2d 219, 224

n.11 (D.C. Cir. 1984)). On the other hand, there are also

situations where prejudice need not be shown by petitioners
29

in a notice-and-comment rulemaking challenge, ‘‘where the

agency has entirely failed to comply with notice-and-comment

requirements, and the agency has offered no persuasive

evidence that possible objections to its final rules have been

given sufficient consideration.’’ Id. at 752. Either way, a

rule requiring petitioners in all ‘‘logical outgrowth’’ cases to

show what additional comments they would have submitted

had notice been adequate would improperly merge the analysis on the merits of whether the final rule is a ‘‘logical

outgrowth’’ with any applicable prejudice analysis. We therefore leave open the possibility that there may be situations

where a petitioner who challenges an agency ‘‘logical outgrowth’’ argument is unable to provide a proffer of additional

comments for valid reasons, but note that in the instant case

petitioners have not offered any such reason.

We nonetheless consider petitioners’ failure to suggest how

their comments would have been different as a factor in our

‘‘logical outgrowth’’ analysis, separate from any analysis as to

whether petitioners were prejudiced by any alleged procedural flaws. We do this because where the final rule falls within

the range of the alternatives addressed in the agency’s initial

cost-benefit analysis, such a failure shows that for notice-andcomment purposes, the initial proposal and the final rule were

essentially the same. Given the proximity, both higher and

lower, of the adopted MCL to the proposed MCLs, the fact

that petitioners were unable to present any additional and

new comments that would have been raised had they been

aware of the 30 mg/L proposal, and the fact that petitioners

have not identified any comment they would have presented

regarding EPA’s interpolation method, the court has no basis

on which to conclude that EPA failed to comply with the

SDWA’s cost-benefit analysis requirement or violated the

notice-and-comment requirements of the SDWA and the

APA.

V. THE MERITS OF THE RADIUM MCLs

Next, petitioners challenge the MCLs EPA set for radium226 and radium-228. We review the rulemaking proceeding

and the final rule under the APA and ‘‘will reverse an EPA

action only if it is ‘arbitrary, capricious, an abuse of discre-
30

tion, or otherwise not in accordance with law.’ ’’ Int’l Fabricare Inst. v. EPA, 972 F.2d 384, 389 (D.C. Cir. 1992) (quoting

5 U.S.C. § 706(2)(A)). Further, we ‘‘will give an extreme

degree of deference to the agency when it ‘is evaluating

scientific data within its technical expertise.’ ’’ Huls Am.,

Inc. v. Browner, 83 F.3d 445, 452 (D.C. Cir. 1996) (quoting

Int’l Fabricare Inst., 972 F.2d at 389; citing Marsh v. Oregon

Natural Res. Council, 490 U.S. 360, 377 (1989)). Nonetheless, our review must ‘‘ensure that the EPA has examined the

relevant data and has articulated an adequate explanation for

its action.’’ Int’l Fabricare Inst., 972 F.2d at 389.

As noted above, EPA set interim MCLs for each isotope at

5 pCi/L in 1976 and in 1991 proposed a new MCL of 20 pCi/L

for each. See 56 Fed. Reg. at 33,082. The agency based the

1991 MCLs on the ‘‘RADRISK’’ risk assessment model, with

adjustments to conform with data from epidemiological studies. See id. at 33,056, 33,073-74. In the 2000 Final Rule the

agency used a newer risk assessment model, set out in

‘‘Federal Guidance Report No. 13,’’ Keith F. Eckerman et al.,

EPA, Federal Guidance Report No. 13: Cancer Risk Coefficients for Environmental Exposure to Radionuclides (1999)

(hereinafter ‘‘FGR-13’’), see 65 Fed. Reg. at 76,735, and,

based thereon, decided to retain the original 1976 MCLs of 5

pCi/L, see id. at 76,712, 76,748 (codified at 40 C.F.R.

§ 141.66). Petitioners contend that EPA’s decision to retain

the lower MCLs violates the SDWA because it is not based

on the ‘‘best available science,’’ as required by the 1996

amendments to the SDWA which state that:

In carrying out this section, and, to the degree that an

Agency action is based on science, the Administrator

shall use—(i) the best available, peer-reviewed science

and supporting studies conducted in accordance with

sound and objective scientific practices; and (ii) data

collected by accepted methods or best available methods

(if the reliability of the method and the nature of the

decision justifies use of the data).

42 U.S.C. § 300g-1(b)(3)(A). We disagree.

Petitioners’ primary contention is that EPA ignored the

epidemiological studies on which it relied in 1991 and failed to
31

reconcile the results of the FGR-13 model with the data

therefrom. Specifically, petitioners point to studies of watch

dial painters who, in the early 20th century, ingested radium226 and radium-228 when they inserted luminescent paint

brushes into their mouths to sharpen the tips. In 1991 EPA

modified the results of the RADRISK assessment in response

to concerns expressed by EPA’s Science Advisory Board

(‘‘SAB’’), based on epidemiological evidence that included the

dial painter data, that the results overstated the risk of

leukemia and understated the risk of head cancer. Petitioners contend the agency arbitrarily ignored the dial painter

data. Contrary to petitioners’ claim, the record reveals that

the agency did rely in part on the dial painter data which are

reflected to some degree in the FGR-13 model. In other

respects the agency adequately explained its reasons for

rejecting the data.

First, the FGR-13 model’s coefficients for both leukemia

and bone cancer were adjusted to compensate for their overand under-prediction, respectively, based on the results of the

dial painter studies. See FGR-13 at 174 (citing as basis for

FGR-13 leukemia ‘‘relative biological effectiveness’’ factor

1994 EPA document ‘‘Estimating Radiogenic Risks,’’ which,

in turn, explains that factor was adjusted because of evidence

it was too high, citing 1991 proposed rulemaking); 65 Fed.

Reg. at 76,722 (citing dial painter data as basis for doubling

risk coefficient for head and bone cancer combined).14 In

14 As part of this challenge, petitioners also contend that EPA

failed its obligation under § 1412(b) to explain ‘‘the methodology

used to reconcile inconsistencies in the scientific data’’ in a ‘‘comprehensive, informative, and understandable manner.’’ Petitioners’ Br.

at 40, 44. After EPA pointed out that the 1991 RADRISK corrections for leukemia and head cancer were included in FGR-13,

Respondent’s Br. at 69–70, petitioners stated that, even if true, this

was not obvious from the EPA documents and therefore not presented in a ‘‘comprehensive, informative, and understandable manner,’’ Petitioners’ Reply Br. at 36–37. However, because

RADRISK and FGR-13 are consistent and because petitioners

never raised the issue of the analysis of leukemia and head cancer

by FGR-13 in their comments before the agency, cf. Northside
32

large part, however, the FGR-13 model relies on alternative

epidemiological data from studies of Hiroshima and Nagasaki

atomic bomb survivors and, to a lesser extent, studies of

medical exposure to radium-224, FGR-13 at 173, and provides

substantial reasons for doing so. The Final Rule sets forth

specific grounds for downplaying the dial painter studies: (1)

‘‘no one knows the quantity of radium ingested in those

studies, so dose estimates are speculative’’ and (2) ‘‘the high

mortality in some groups, and the small numbers of subjects

in all exposure groups, would impair use of the data to

develop dose response relationships.’’ 65 Fed. Reg. at

76,721; see also Comment-Response Document 3-11 to 3-13

(response to comment 3.B.3). In addition, the FGR-13 model

identifies a number of advantages to the alternative epidemiological data, in particular the bomb survivor studies: the

‘‘large, relatively healthy population at the time of exposure,’’

‘‘wide range of reasonably well established doses to individual

subjects,’’ ‘‘large, well matched control group,’’ and ‘‘detailed,

long-term epidemiological follow-up.’’ FGR-13 at 173.

Without contesting the factual bases for EPA’s preference,

see Petitioners’ Br. at 40 (‘‘[T]hese observations may be

accurate.’’), petitioners point to disadvantages they see in the

alternative data: the bomb studies also involve estimates, the

bombing contamination was not limited to radium-226 and

-228 and the contamination was largely external exposure

rather than ingestion. Given the relative advantages EPA

found in the bomb survivor studies, however, we defer to its

decision to use the FGR-13 model because it bears a ‘‘rational

relationship to the characteristics of the data to which it is

applied.’’ See Nat’l Wildlife Fed’n v. EPA, 286 F.3d 554, 565

(D.C. Cir. 2002) (‘‘We may reject an agency’s choice of a

scientific model ‘only when the model bears no rational relationship to the characteristics of the data to which it is

applied.’ ’’) (quoting Appalachian Power Co. v. EPA, 135 F.3d

791, 802 (D.C. Cir. 1998) (citing Am. Iron & Steel Inst. v.

Sanitary Landfill, Inc. v. Thomas, 849 F.2d 1516, 1521 (D.C. Cir.

1988), there was no need under the statute for EPA to ‘‘reconcile’’

any ‘‘inconsistencies’’ pursuant to § 1412(b)(3)(B)(v).
33

EPA, 115 F.3d 979, 1005 (D.C. Cir. 1997); Chem. Mfrs. Ass’n

v. EPA, 28 F.3d 1259, 1265 (D.C. Cir. 1994))); cf. Am. Forest

& Paper Ass’n, Inc, 294 F.3d 113, 121 (D.C. Cir. 2002)

(applying ‘‘rational relationship’’ standard and upholding

EPA’s reasoned preference for one methodology of calculating safe exposure levels over alternative methodology). We

also conclude that EPA adequately responded to comments

critiquing its reliance on the bomb studies.

Petitioners further contend that the dial painter data require the use of a quadratic dose-response curve for bone

cancer, that is, one based on ‘‘ ‘a model which assumes that

the excess risk is proportional to the square of the dose,

meaning that low dosage presents no appreciable cancer

risk,’ ’’ Respondent’s Br. at 68 n.32 (quoting Nat’l Acad. of

Scis. Comm. on the Biological Effects of Ionizing Radiation,

Health Risks of Radon and Other Internally Deposited Alpha-Emitters IV (1988)) (emphasis added), rather than the

linear, non-threshold (‘‘LNT’’) model used by EPA, which

assumes that the risk is directly proportional to the dosage

and that there is no threshold dosage below which there is no

risk, see FGR-13 at v. Here, again, the agency sufficiently

justified its choice of model to satisfy the ‘‘rational relationship’’ standard.

First, while acknowledging that the dial painter data suggest a quadratic, rather than linear, dose response curve,

EPA concluded that the data are ‘‘of limited value for the

estimation of risk’’ because the various reliability problems

noted above (‘‘radium dosimetry, the high mortality in some

groups, and the small numbers of subjects in all exposure

groups’’) ‘‘would impair use of the data to develop dose

response relationships.’’ 65 Fed. Reg. at 76,721. In particular, EPA concluded that ‘‘there just are not enough subjects

at lower dose levels to show the risk, giving the illusion of a

threshold.’’ Id. at 76,722.

Petitioners also assert the radium-224 exposure study results, from which EPA inferred that radium-226 and -228 can

cause cancer of body parts other than the bone or head, are

misleading because isotope -224 has different emissions from
34

-228 and a far shorter half-life than either -226 or -228.

Petitioners point out that EPA itself observed in the NODA

that such different characteristics can affect human health

differently. EPA made the observation, however, in explaining why -224 had been and might again be considered less

risky in degree than the other two isotopes, not because of

any qualitative difference in effect. See 65 Fed. Reg. at

21,585–86. Petitioners further contend that there were no

data showing that any radium isotope, even radium-224,

caused cancer in the esophagus, stomach, colon, lung, skin,

ovary, or kidney. Petitioners’ Br. at 43. In the Final Rule,

however, EPA expressly states that ‘‘patients treated with

radium-224 were found to have significant increases in breast

cancer, soft tissue sarcomas, liver cancer, thyroid cancer,

cancers of urinary organs, and leukemia.’’ 65 Fed. Reg. at

76,722 (emphasis added). ‘‘Soft tissue sarcomas,’’ EPA points

out, ‘‘can include any tissue in the body except cortical and

trabecular bone.’’ Respondent’s Br. at 72 n.34 (citing FGR13 at GL-9). In sum, EPA was justified in relying on the

radium-224 studies for its conclusion that, ‘‘[g]iven our understanding of radium metabolism and the effects of alpha

irradiation, it is expected that ingestion of any of the radium

isotopes will increase the risks for various types of cancer

other than bone.’’ 65 Fed. Reg. at 76,722.

As additional justification for its model choice, EPA noted

that the LNT model derives support ‘‘from the linear doseresponse relationships observed for most types of cancers in

the intermediate- to high-dose range for atomic bomb survivors, and from results of molecular and cellular studies.’’ 65

Fed. Reg. at 76,721. The latter studies, EPA explained,

‘‘have shown that a single radiation track traversing a cell

nucleus can cause unrepaired or misrepaired DNA lesions

and chromosomal aberrations’’ and ‘‘that DNA lesions and

chromosomal aberrations can lead to cancer.’’ Id. From

these data, EPA inferred, logically enough, ‘‘that the probability of DNA damage and carcinogenesis is linearly proportional to the dose.’’ Id. EPA further noted that its use of

the LNT model for radionuclides ‘‘is entirely consistent with

all past and current observations and recommendations’’ of a
35

number of national and international science organizations20

and that ‘‘the U.S. Department of Energy, the U.S. Nuclear

Regulatory Commission, and other Federal and State agencies with regulatory authority over radioactive materials also

apply the LNT model as the basis for setting regulations and

guidelines for radiation protection.’’ Id.; see also FGR-13 at

v (‘‘[S]everal recent expert panels ([United Nations Scientific

Committee on the Effects of Atomic Radiation 1993, 1994;

National Radiation Protection Board 1993; and the National

Council on Radiation Protection and Measurements 1997])

have concluded that the LNT model is sufficiently consistent

with current information on carcinogenic effects of radiation

that its use is scientifically justifiable for purposes of estimating risks from low doses of radiation. As a practical matter,

the LNT approach is universally used for assessing the risk

from environmental exposure to radionuclides as well as other

carcinogens.’’)21

Finally, petitioners contend EPA did not demonstrate that

the FGR-13 model represents the ‘‘best available, peerreviewed science,’’ as required by § 1412(b)(3)(A) (‘‘In carry20 The agency identified in particular the International Commission on Radiological Protection, the National Council on Radiation

Protection and Measurements, the National Academy of Sciences

Committee on the Biological Effects of Ionizing Radiation, the

United Nations Scientific Committee on the Effect of Atomic Radiation, and the National Radiation Protection Board. 65 Fed. Reg. at

76,721.

21 EPA also stated:

[T]o address [the] limitations and the uncertainties associated

with this model and improve its radiation risk assessments,

EPA is actively supporting national and international studies of

radiation dosimetry and dose reconstruction, radionuclide biokinetics, quantitative techniques for uncertainty analyses, and

long-term follow-up epidemiological studies of populations exposed chronically to low-dose radiation. The Agency also

continues to review its policies and positions as new reports

and data are published so that the best science is applied.

65 Fed. Reg. at 76,721.
36

ing out this section, and, to the degree that an Agency action

is based on science, the Administrator shall use—(i) the best

available, peer-reviewed science and supporting studies conducted in accordance with sound and objective scientific practicesTTTT’’). As set out above, however, EPA adequately

explained, based on scientific data, why it prefers the FGR-13

model and the epidemiological data it used over the dial

painter studies and the approaches based thereon that petitioners endorse. Further, as EPA notes, the SAB, whose

imprimatur petitioners particularly esteem, reviewed and approved the FGR-13 methodology as it was employed in a 1994

EPA document ‘‘Estimating Radiogenic Cancer Risks,’’ and

also reviewed and commented on the interim version reported

in 1998, see FGR-13 at vi.22 The substantial scientific support

on which EPA relies for selecting the FGR-13 model (and in

particular its LNT approach) distinguishes this case from

Chlorine Chemistry Council v. EPA, 206 F.3d 1286 (D.C. Cir.

2000), in which the court found EPA’s use of a default

assumption of linearity and zero MCLG violated the SDWA

because it ‘‘openly overrode the ‘best available’ scientific

evidence, which suggested that chloroform is a threshold

carcinogen’’—a concession EPA had made at oral argument

in that case. See 206 F.3d at 1290, 1291.

22 Petitioners also contend in their reply brief that EPA violated

§ 1412(b)(3)(B) by failing to specify ‘‘an upper bound, lower bound,

and central risk estimate’’ or to identify ‘‘the range of alternative

risk estimates produced by other methods that use the dial painter

studies,’’ Petitioners’ Reply Br. at 37, and ignored the congressional directive ‘‘to inform the public of ‘alternative risk estimates that

put the regulation in broader public health context,’ ’’ id. (quoting S.

Rep. No. 104-169, at 29). Because this argument was raised in the

opening brief only summarily, without explanation or reasoning, see

Petitioners’ Br. at 33–34, 49, and first raised comprehensibly only in

the reply brief, it is waived. See Tribune Co. v. FCC, 133 F.3d 61,

69 n.8 (D.C. Cir. 1998) (noting ‘‘our requirement that a parties’ [sic]

arguments be sufficiently developed lest waived’’); Steel Joist Inst.

v. OSHA, 287 F.3d 1165, 1166 (D.C. Cir. 2002) (argument presented

for first time in reply brief held waived) (citing Benkelman Telephone Co. v. FCC, 220 F.3d 601, 607 n.10 (D.C. Cir. 2000)).
37

VI. THE MERITS OF THE URANIUM MCLs

Petitioners also challenge EPA’s determination of both the

MCLG at 0 mg/L and the MCL at 30 mg/L for uranium on the

merits of the science used by EPA. They make three

challenges to the MCLG and assert that EPA’s reliance on an

improper MCLG tainted its MCL determination, as did

EPA’s reliance on kidney toxicity data. Regarding the

MCLG, petitioners contend that (1) ‘‘the best available peerreviewed science,’’ 42 U.S.C. § 300g-1(b)(3)(A)(i), does not

support a 0 mg/L MCLG because the LNT model used by

EPA is not supported by the science; (2) under EPA’s

classification system for carcinogens, a 0 mg/L MCLG is

inappropriate; and (3) EPA ignored a report by the Agency

for Toxic Substances and Disease Registry (‘‘ATSDR’’) on the

toxicity of uranium. Finally, petitioners also argue that EPA’s

cost-benefit decision, which determined the final level for the

MCL, was substantively flawed.

In setting the uranium standard, EPA first set the MCLG

for uranium based on the risks of carcinogenicity. 65 Fed.

Reg. at 76,712. EPA reasoned that because natural uranium

is a radionuclide, and all radionuclides emit ionizing radiation

that can cause cancer, there was no threshold level of safety

for uranium. Id. EPA then concluded that the lowest

feasible level for controlling the risks of cancer from natural

uranium in drinking water was 20 mg/L. Id. Next, EPA

addressed the effects of uranium on the human kidney,

deciding that the best available science showed that uranium

did have toxic effects on the human kidney, and that the level

of uranium in drinking water that could be expected to

protect human health was 20 mg/L. Id. at 76,713. EPA

added that 30 mg/L would be expected to protect against the

effects of kidney toxicity, id. at 76,713–14, but that any higher

level might result in serious adverse effects on human kidneys, id. at 76,714. Finally, EPA relied on its cost-benefit

analysis to conclude that at 30 mg/L essentially the same

health benefits could be achieved at much lower cost compared to the 20 mg/L level. Id. EPA therefore set the

uranium MCL at 30 mg/L.
38

EPA relied on the LNT model in setting the MCLG for

uranium at zero. 65 Fed. Reg. at 76,712. According to

petitioners, ‘‘there is no evidence in the record to support

linearity and no evidence which detracts from the weight of

the scientific evidence that supports the application of a nonlinear model.’’ Petitioners’ Br. at 52. There was evidence in

the record, primarily provided by RSH, that radionuclides in

general only cause harm above a certain threshold level.

There were also specific critiques of the linearity model as

applied to uranium. However, the bomb studies in the record

provide ample support for the linearity model, see 65 Fed.

Reg. at 76,721, and there is also evidence in the record that

uranium may be a carcinogen without a threshold level of

safety. EPA noted that there is clear evidence that uranium

(as with all radionuclides in general) emits ionizing radiation,

that ionizing radiation causes genetic defects, and that genetic

defects may lead to cancer. See 65 Fed. Reg. at 21,587,

21,600; 65 Fed. Reg. at 76,721. Although this evidence is

based on enriched uranium, that does not exclude the possibility that natural uranium may have the same impact. EPA

noted that the impacts of natural uranium may be difficult to

detect because of the small doses of radiation involved and

the comparatively small changes in cancer risk that would

result; moreover, the pathway for causation would be the

same for both enriched and natural uranium.

The resolution of this contradictory data lies well within

EPA’s expertise. Chlorine Chemistry Council, on which

petitioners rely, is not to the contrary. In that case, the

court concluded that EPA’s reliance on the LNT model was

inappropriate because EPA itself concluded that the chemical

in question (chloroform) only caused harm above a threshold

level. 206 F.3d at 1288. EPA failed to change the MCLG

from zero because it wanted to wait for an additional report

from SAB. Id. The court held that EPA’s decision was

arbitrary and capricious inasmuch as EPA had already concluded that the best science showed that there was a threshold effect, and EPA could always justify delay by stating that

it wanted to wait for additional evidence to come in. Id. at

1290–91. In the instant case, by contrast, EPA maintains
39

that the best available evidence still shows that uranium is a

non-threshold carcinogen. Given the contradictory evidence

in the record, there is no basis for the court to override

EPA’s decision for this is not a situation where ‘‘there is

simply no rational relationship between the model chosen and

the situation to which it is applied.’’ Am. Iron & Steel Inst. v.

EPA, 115 F.3d 979, 1004 (D.C. Cir. 1997) (quotation omitted).

Petitioners’ next contention is that EPA did not follow its

own procedures for classifying carcinogens when it set the

MCLG for uranium at zero. According to petitioners, EPA

classifies substances as having an MCL of zero when the

substance falls into one of three groups:

Group A, human carcinogens based on strong evidence of

carcinogenicity from drinking water ingestion or sufficient evidence from epidemiological studies; Group B-1,

probable human carcinogen based on at least limited

evidence of carcinogenicity based on epidemiological

studies in humans; Group B-2, probable human carcinogen based on sufficient evidence in animals and inadequate evidence or no data from epidemiological studies in

humans.

Petitioners’ Br. at 53. EPA does not contest petitioners’

characterization of its classification process, but denies that it

misapplied it in this case.

Apparently EPA classifies all radionuclides as Group A

carcinogens based on the fact that they emit ionizing radiation that can cause cancer. 65 Fed. Reg. at 76,721. Again,

this is a reasonable conclusion by EPA based on the evidence

in the record. EPA is not relying on data from natural

uranium, any effect of which EPA has concluded might be

very difficult to detect through epidemiological or laboratory

studies, but instead is relying on an extrapolation from other

radionuclides and the laboratory and epidemiological data

associated with those compounds. See 65 Fed. Reg. at 76,-

721; see also 56 Fed. Reg. at 33,071–72. Although studies to

date may not have detected any impacts of natural uranium

on cancer rates when it is ingested in drinking water in

humans, EPA could reasonably conclude that based on the
40

known carcinogenic potential of similar substances, natural

uranium should also be considered a Group A carcinogen.

Petitioners make much of statements by EPA in its proposed rule in 1991 on a uranium MCLG, where EPA noted

that ‘‘[s]tudies using natural uranium do not provide direct

evidence of carcinogenic potential’’ in animals and that ‘‘[e]xisting human epidemiology data are inadequate to assess the

carcinogenicity of uranium ingested in drinking water.’’ 56

Fed. Reg. at 33,076. However, EPA continued to explain in

those statements that there were limitations to the studies

that had found no effect, that other radionuclides were known

to be harmful, that the pathways by which those radionuclides

caused harm would be the same as for natural uranium, and

that therefore the agency would continue to classify natural

uranium as a Group A carcinogen. Id.

Petitioners also maintain that EPA improperly relied on

data that uranium causes cancer by inhalation in concluding

that it should be a Group A carcinogen, and state that this ‘‘is

a fatal flaw.’’ Petitioners’ Br. at 55. It is true that EPA has

generally declined to rely on inhalation data when making

decisions about the carcinogenic properties of a substance

when ingested. See Int’l Fabricare Inst., 972 F.2d at 395.

However, the statements made in the 1991 proposed rule do

not indicate that EPA significantly relied upon the inhalation

data. 56 Fed. Reg. at 33,076.

Petitioners further maintain that EPA should be forced to

treat radionuclides in the same manner that it treated asbestos, where EPA concluded that despite asbestos’ status as a

Group A or B chemical, it would not automatically be treated

as a non-threshold carcinogen because the agency believed

that the ‘‘additional evidence indicates that the overall evidence of carcinogenicity via ingestion is limited or inadequate.’’ National Primary Drinking Water Regulations; Final Rule, 56 Fed. Reg. 3,526, 3,534 (Jan. 30, 1991). However,

as EPA points out, asbestos is a completely different chemical

from natural uranium. Given the evidence for similar radionuclides, EPA could reasonably conclude that the minimal

direct evidence for natural uranium’s carcinogenicity should
41

be treated differently from the slightly more substantial

direct evidence for asbestos.

Finally, petitioners contend that EPA ignored a report by

the ATSDR on the risks of natural uranium. The ATSDR

report concluded that:

No evidence linking oral exposure to uranium to human

cancer has been found. Although natural, depleted, or

enriched uranium and uranium compounds have not been

evaluated in rodent cancer bioassays by any route by the

[National Toxicology Program], there is potential for the

carcinogenicity of uranium, since it emits primarily alpha

radiation. Nevertheless, no evidence has been found to

associate human exposure to uranium compounds and

carcinogenicity. The National Academy of Sciences has

determined that bone sarcoma is the most likely cancer

from oral exposure to uranium; however, their report

noted that this cancer has not been observed in exposed

humans and concluded that exposure to natural uranium

may have no measurable effect.

Similarly, the results of several oral studies with uranium in several species were negative for evidence of

cancer induction.

ATSDR, U.S. Dep’t of Health and Human Servs., Toxicological Profile for Uranium 137–38 (1999) (citations omitted). In

replying to commenters who relied on the ATSDR report,

EPA stated that ‘‘ATSDR’s statement does not preclude

human carcinogenesis.’’ Comment-Response Document (response to comment 9.A.4). This appears to be a correct

reading of the ATSDR report, and, again, EPA is generally

entitled to rely on evidence from other radionuclides and the

potential for cancer from natural uranium’s emission of ionizing radiation in the face of the uncertainty inherent in any

scientific study’s failure to identify a significant effect. Nor

does EPA’s failure to mention the ATSDR in its NODA or its

technical documents that accompanied the NODA mean, as

petitioners maintain, that EPA did not rely on the ‘‘best

available science.’’ The ATSDR report is not primary research based on ATSDR’s own studies; instead, it is a
42

summary and review of the literature that has been published, the same type of undertaking that EPA’s NODA and

technical documents performed. We fail to see how EPA’s

failure to mention the ATSDR report in these documents is

fatal to its analysis. Further, EPA’s response to the comments mentioning the ATSDR report is adequate.

Petitioners in a footnote of their reply brief also state,

‘‘While EPA argues that FGR-13 represents EPA’s ‘most

sophisticated science,’ EPA did not utilize FGR-13 to develop

the uranium standard. EPA neither disputes nor discusses

this point in its brief.’’ Petitioners’ Reply Br. at 33 n.150

(citation omitted). Petitioners do not state what legal flaw

results from EPA’s failure to use FGR-13, although the

implication is that EPA did not meet the ‘‘best available

science’’ standard of the SDWA. However, petitioners’ only

references to this argument in their opening brief were two

sentences that also referred to EPA’s failure to discuss FGR13 in setting the uranium MCL, without explaining the legal

implication of that failure. This is the type of ‘‘asserted but

unanalyzed’’ contention that the court will not address. See

SEC v. Banner Fund Int’l, 211 F.3d 602, 613 (D.C. Cir. 2000)

(quoting Carducci v. Regan, 714 F.2d 171, 177 (D.C. Cir.

1983)).

Because EPA’s MCLG is proper, petitioners’ challenge to

the MCL based on the MCLG fails. To the extent petitioners

also challenge EPA’s reliance on kidney toxicity data, data

which it relied upon in setting the MCL at 30 mg/L, the

thrust of petitioners’ challenge is that EPA relied on studies

that ‘‘showed risks so small that EPA could not determine

whether exposure resulted in an adverse impact,’’ that EPA

admitted that human studies were uncertain as to the actual

impacts on kidneys from uranium consumption, and that

EPA’s conclusions were primarily based on data from experiments on rats using uranyl nitrate, a compound of uranium,

rather than natural uranium itself. Petitioners’ Br. at 61.

However, in the face of uncertain laboratory and epidemiological data, it was reasonable for EPA to take the risk-averse
43

approach of relying on the animal laboratory data to develop

a lower standard.

Regarding petitioners’ challenge to EPA’s decision to set

the final MCL at 30 mg/L based on its cost-benefit analysis,

the court’s review is limited to determining whether EPA’s

analysis and final cost-benefit decision is arbitrary and capricious. 42 U.S.C. § 300g-1(b)(6)(D). Petitioners contend that

EPA ‘‘should have compared the cost per cancer case avoided’’:

When EPA selected from the acceptable uranium levels,

EPA should have compared the cost per cancer case

avoided for each proposed uranium MCL. EPA did not

do that. Had the agency done so, it would have found

that the incremental cost savings associated with raising

the standard from 30 mg/L to 40 mg/L ($64.1 million) was

even higher than the incremental cost savings that

prompted EPA to raise the standard from 20 mg/L to 30

mg/L ($45.2 million) while still achieving an acceptable

cancer risk. Thus if EPA applied the same analysis to

the cost differences between 30 mg/L and 40 mg/L, as it

did to the costs between 20 mg/L to 30 mg/L, it would

have concluded that an increase to 40 mg/L was appropriate.

Petitioners’ Br. at 32. The figures that petitioners cite in

their brief are the aggregate amounts of money saved by

relaxing the standards; at no point did petitioners discuss the

increase in the number of cancer deaths or cases that would

occur if the standards were relaxed. By definition, however,

that increase must be considered in order to compare ‘‘the

cost per cancer case avoided,’’ as petitioners request. In

other words, petitioners’ contention is internally inconsistent.

Furthermore, a review of EPA’s cost-benefit analysis shows

that the cost per cancer case avoided is lower between 30 and

40 mg/L compared to between 20 and 30 mg/L, contrary to

petitioners’ assertions. Most importantly, EPA concluded

that kidney risks increased substantially above 30 mg/L,

sharply increasing the benefits foregone by raising the stan-
44

dard above that point. 65 Fed. Reg. at 76,713-14. EPA’s

decision therefore was not arbitrary and capricious.

VII. THE MERITS OF THE BETA/PHOTON MCLs

As noted above, the 1996 amendments to the SDWA state

that:

In carrying out this section, and, to the degree that an

Agency action is based on science, the Administrator

shall use—(i) the best available, peer-reviewed science

and supporting studies conducted in accordance with

sound and objective scientific practices; and (ii) data

collected by accepted methods or best available methods

(if the reliability of the method and the nature of the

decision justifies use of the data).

42 U.S.C. § 300g-1(b)(3)(A). Petitioners contend that, because EPA did not use today’s ‘‘best available science’’ when

it promulgated beta/photon MCLs in 1976, it violated

§ 1412(b)(3)(A)’s ‘‘best available science’’ requirement (as well

as the APA) by retaining those pre-existing MCLs in 2000.

What EPA should have done in 2000, petitioners insist, is

apply the latest risk assessment model—set out in FGR-13—

to establish uniform risk at a level EPA deemed appropriate.

EPA does not dispute that it utilized now-outdated methods

to predict mortality and morbidity rates for beta/photon

emitters in promulgating the 1976 MCLs. The methodology

EPA used in 1976 did not differentiate among various

beta/photon emitters and their effects on particular organs

within the body. See 65 Fed. Reg. at 21,602–03. The agency

further admits that a newer ‘‘effective dose equivalent’’ methodology, which accounts for a particular organ’s sensitivity to

radiation, is now available, and that FGR-13 incorporates the

newer methodology. See id.; Respondent’s Br. at 83. Indeed, both parties agree that, for purposes of this challenge

to the beta/photon MCLs, FGR-13 represents the ‘‘best available science.’’ See Petitioners’ Reply Br. at 45; Respondent’s

Br. at 83.

EPA nonetheless insists that it complied with the SDWA’s

‘‘best available science’’ requirement, because it used FGR-13
45

for the analysis that led to its 2000 decision to retain the 1976

MCLs. That analysis disclosed that the 1976 MCLs continue

in virtually all cases to confine health risks within the acceptable range of between 1 x 10-4 and 1 x 10-6 (1 in 10,000 to 1 in

1,000,000) lifetime excess risk of cancer. 65 Fed. Reg. at

21,583, 21,605–14 tbl. II-3. Moreover, EPA also used FGR-13

to evaluate the new beta/photon MCLs that the agency

proposed in 1991. EPA decided to retain the 1976 levels in

favor of the 1991 proposals because FGR-13 showed that the

latter were in almost all cases outside the acceptable range

and less protective of human health than the 1976 levels. Id.

We see nothing unreasonable about EPA’s assertion that this

approach was consistent with the ‘‘best available science,’’ and

nothing arbitrary about its decision to retain the 1976 MCLs

under these circumstances.

Petitioners do not seriously dispute that EPA used the

‘‘best available science’’ to analyze the health risks posed by

the 1976 and proposed 1991 MCLs.23 Instead, they argue

that the ‘‘best available science’’ should have led the agency to

promulgate beta/photon MCLs that provide a uniform level of

protection. Although in 1976 EPA thought that the more

than 160 beta/photon MCLs it was setting would yield a

consistent risk level of 5.6 x 10-5 for each beta/photon emitter,

EPA’s current analysis discloses that each MCL actually

yields a different risk level. See id. at 21,582 fig.1; id. at

21,605–14 tbl. II-3. Because it is possible to use FGR-13 to

establish MCLs with uniform protection levels, petitioners

contend that it contradicts the ‘‘best available science’’ not to

do so.

23 Petitioners did assert in their opening brief that EPA’s application of FGR-13 risk coefficients to MCLs derived under different

methodologies yielded ‘‘an analysis that combined and compared

multiple, incompatible generations of science, which necessarily

yielded inconsistent and incomparable results.’’ Petitioners’ Br. at

75. But EPA reasonably responded that all of the relevant methodologies result in dose limits expressed in pCi/L, which unit is

compatible with FGR-13’s risk coefficients. Respondent’s Br. at

85–86. Petitioners did not return to this issue in their reply brief.
46

But just because science makes a result possible, does not

mean that it would contradict the ‘‘best available science’’ not

to achieve it. Indeed, as petitioners conceded at oral argument, there is nothing in the record—neither scientific studies nor anything else—to suggest that the ‘‘best available

science’’ itself requires uniformity in risk protection. Nor is

there anything in the SDWA that requires that the level of

risk protection provided for each contaminant be the same.

Accordingly, whether to insist upon uniformity is a policy

judgment that the SDWA leaves to EPA’s discretion.24

In this case, EPA concluded that uniformity was not a goal

it should strive to achieve for the beta/photon MCLs. The

agency noted that to produce uniformity, it would have to

undertake an extensive new rulemaking process. 65 Fed.

Reg. at 21,581. And it reasonably concluded that such an

effort was unnecessary because, while the actual level of risk

posed by the 1976 MCLs varies, in virtually all cases it is

within the range regarded as acceptable both in 1976 and

today, and below the level of risk expected in 1976. See id. at

21,582 fig.1; id. at 21,605–14 tbl. II-3. Of the more than 160

existing MCLs, all but ten yield risks below the agency’s

upper limit of 1 x 10-4. Respondent’s Br. at 83; Tape of Oral

Argument, Nov. 20, 2002; see also 65 Fed. Reg. at 21,605–14

tbl. II-3. Of those ten, only one (cesium) is likely to be found

at decommissioning sites, and none is likely to be found in

drinking water. See 65 Fed. Reg. at 21,583; Tape of Oral

Argument, Nov. 20, 2002.

Uniformity, of course, is not the only thing petitioners are

after. Their ultimate aim is to raise at least some of the

MCLs, and, accordingly, they argue that the existing MCLs

are ‘‘artificially low and unnecessarily conservative.’’ Petitioners’ Br. at 64. Perhaps for this reason, petitioners sug24 The SDWA plainly contemplates that not all agency decisions

under the Act will be science-based. See 42 U.S.C. § 300g1(b)(3)(A) (‘‘In carrying out this section, and, to the degree that an

Agency action is based on science, the Administrator shall use—(i)

the best available, peer-reviewed scienceTTTT’’ (emphasis added)).
47

gest that EPA had no reasonable basis for distinguishing

between the 1976 MCLs and the substantially higher MCLs

proposed in 1991. But as noted above, EPA did have a

rational basis for preferring the 1976 MCLs over those

proposed in 1991: the 1991 proposed levels were in almost all

cases less protective of human health than the 1976 levels and

outside the range of acceptable cancer risk. 65 Fed. Reg. at

21,583; see id. at 21,582 fig.1; id. at 21,605–14 tbl. II-3.

Moreover, although there is nothing in the record to suggest that the ‘‘best available science’’ requires uniformity,

even if it did the anti-backsliding provision of § 1412(b)(9)

would still prevent the agency from raising the MCLs above

those set in 1976. That provision imposes a limitation on any

revision ‘‘promulgated in accordance with this section,’’ 42

U.S.C. § 300g-1(b)(9), and the ‘‘best available science’’ provision is a part of the same referenced section, see id. § 300g1(b)(3)(A). Section (b)(9)’s limitation is as follows: ‘‘[E]ach

revision shall maintain, or provide for greater, protection of

the health of persons.’’ Id. § 300g-1(b)(9). Once again,

petitioners contend that § (b)(9) does not preclude an increase in an MCL when current science shows that the MCL

can be increased without reducing the level of protection the

agency initially thought it was providing. See supra Part

III.B. And, once again, we accept as reasonable EPA’s

reading of the section as barring any revision to an existing

MCL that does not maintain the level of protection the

current MCL actually provides. See id. Hence, EPA could

not achieve the uniformity for which petitioners argue without

lowering most of the 1976 beta/photon MCLs until they yield

the risk level actually provided by the most protective of

those MCLs—a result petitioners do not seek and that would

defeat their aim in bringing this petition.

In sum, we conclude that EPA neither failed in its obligation to use the ‘‘best available science’’ nor acted arbitrarily

or capriciously in retaining the 1976 beta/photon MCLs.

VIII. FAILURE TO RESPOND TO COMMENTS

Finally, petitioners contend EPA did not adequately respond to comments submitted in opposition to using the LNT
48

model. Section 553 of the APA requires that an agency

‘‘shall give interested persons an opportunity to participate in

the rule making through submission of written data, views, or

arguments with or without opportunity for oral presentation’’

and, ‘‘[a]fter consideration of the relevant matter presented,

TTT shall incorporate in the rules adopted a concise general

statement of their basis and purpose.’’ 5 U.S.C. § 553(c).

The agency ‘‘need not address every comment, but it must

respond in a reasoned manner to those that raise significant

problems.’’ Reytblatt v. Nuclear Regulatory Comm’n, 105

F.3d 715, 722 (D.C. Cir. 1997) (citing Action on Smoking &

Health v. CAB, 699 F.2d 1209, 1216 (D.C. Cir. 1983)). Nevertheless, ‘‘ ‘[t]he failure to respond to comments is significant

only insofar as it demonstrates that the agency’s decision was

not based on a consideration of the relevant factors.’ ’’ Texas

Mun. Power Agency v. EPA, 89 F.3d 858, 876 (D.C. Cir.

1996) (quoting Thompson v. Clark, 741 F.2d 401, 409 (D.C.

Cir. 1984); alteration in original). The record here does not

demonstrate that EPA failed to consider the relevant factors.

Petitioners object to EPA’s ‘‘general and generic’’ response

to comments, citing specific studies that they contend reflect

the ‘‘best available science’’ and show the LNT model is

inappropriate. In its first response to a comment challenging the LNT model and zero MCLG (frequently crossreferenced in responses to later comments), EPA summarized its reasons for choosing the LNT model and stated it

had ‘‘reviewed the documents submitted by the commenter

that purport to provide new scientific evidence to counter the

Agency’s position that there is ‘no threshold’ for carcinogens

such as the radionuclides,’’ that ‘‘much of the information in

these documents was familiar to the Agency and accordingly

had already been considered’’ and that ‘‘the submissions cite

anecdotal or case report data, provide comment on other documents or positions or policy decisions, or selected observations’’ and ‘‘do not provide the kind of data that EPA discusses in the remainder of this response.’’ Comment-Response

Document 3-5 (response to comment 3.A.1). This response

demonstrates that the agency considered and rejected petitioners’ arguments (and cited support) for adopting the quad-
49

ratic model over the LNT model—an issue the agency had

already thoroughly addressed in the rulemaking proceeding.

This is all that the APA requires.25 See Am. Iron & Steel

Inst. v. EPA, 115 F.3d 979, 1005 (D.C. Cir. 1997) (finding

comment response sufficient if it ‘‘demonstrates that the

agency at least considered whether it should adopt [an alternative] model’’); Thompson, 741 F.2d at 409-10 (concluding

that ‘‘nothing had been presented which required some explanation beyond that already contained within the rulemaking record to assure [the court] that ‘all relevant factors

ha[d] been considered’ ’’) (quoting Home Box Office v. FCC,

567 F.2d 9, 36 (D.C. Cir. 1977)).26 Accordingly, we reject

petitioners’ challenge to the adequacy of EPA’s responses to

their comments.

IX. CONCLUSION

For these reasons, the petition for review filed by RSH is

dismissed for lack of standing, and the remaining petitions for

review are denied.

So ordered.

25 Petitioners’ counsel made it clear at oral argument that their

objections to the comment responses are procedural ones, addressed only to the sufficiency of the responses, and are not

intended as substantive challenges to the merits.

26 The response also recited that ‘‘[d]etailed responses to the

issues raised and the arguments presented in those submissions

[would] follow[ ],’’ and, in many cases, EPA did provide more

specific critiques of particular studies. See, e.g., CommentResponse Document 3-14 (response to comment 3.B.5), 3-30 (comment 3.B.16), 3-28 (comment 3.B.23), 3-29 (comment 3.B.26-27).