Maine People's Alliance & Natural Resources Defense Council v. Mallinckrodt, Inc.

United States Court of Appeals
For the First Circuit

No. 05-2331

MAINE PEOPLE'S ALLIANCE AND
NATURAL RESOURCES DEFENSE COUNCIL,

Plaintiffs, Appellees,

v.

MALLINCKRODT, INC.,

Defendant, Appellant.

APPEAL FROM THE UNITED STATES DISTRICT COURT

FOR THE DISTRICT OF MAINE

[Hon. Gene Carter, Senior U.S. District Judge]

Before

Selya and Howard, Circuit Judges,
and Smith,* District Judge.

Carter G. Phillips, with whom Joseph R. Guerra, J. Andrew
Schlickman, John M. Heyde, and Sidley Austin LLP were on brief, for
appellant.
Mitchell S. Bernard, with whom Nancy S. Marks, Eric J. Uhl,
and Moon, Moss & Shapiro, P.A. were on brief, for appellees.

December 22, 2006

________
*Of the District of Rhode Island, sitting by designation.
 SELYA, Circuit Judge. In the teeth of two decades of

contrary precedent from four circuits, defendant-appellant

Mallinckrodt, Inc. asks us to restrict the role of private citizens

in the abatement of imminent and substantial threats to the

environment and public health. In support of this entreaty,

Mallinckrodt presents a gallimaufry of new, hitherto unconsidered

arguments. After careful consideration of this asseverational

array, we conclude that our sister circuits have adroitly distilled

the meaning of section 7002(a)(1)(B) of the Resource Conservation

and Recovery Act (RCRA), 42 U.S.C. § 6972(a)(1)(B) — the so-called

citizen suit provision. Correctly interpreted, this provision

allows citizen suits when there is a reasonable prospect that a

serious, near-term threat to human health or the environment

exists.1 In such situations, the provision permits remedies

consistent with the scope of a district court's equitable

discretion.

The district court read the statute in this manner and

faithfully applied the law to the facts. Its supportable liability

finding, coupled with a choice of remedy that comes within the

1
We use the phrase "near-term threat" advisedly. It is the
threat that must be close at hand, even if the perceived harm is
not. For example, if there is a reasonable prospect that a
carcinogen released into the environment today may cause cancer
twenty years hence, the threat is near-term even though the
perceived harm will only occur in the distant future.

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encincture of its discretion, leads us to reject Mallinckrodt's

appeal.

I. BACKGROUND

We rehearse here only those facts that are directly

relevant to the issues on appeal, referring readers who hunger for

more information to the district court's initial opinion. See Me.

People's Alliance v. HoltraChem Mfg. Co., 211 F. Supp. 2d 237 (D.

Me. 2002). This narrative credits the factual findings of the

district court to the extent that those findings are not clearly

erroneous. See Fed. Refinance Co. v. Klock, 352 F.3d 16, 27 (1st

Cir. 2003).

From 1967 to 1982, Mallinckrodt, then called

International Minerals and Chemicals Corporation, owned and

operated a chlor-alkali plant (the Plant) situated on the banks of

the Penobscot River in Orrington, Maine. Thereafter, the Plant

continued operations under other owners, namely, Hanlin Group, Inc.

and HoltraChem Manufacturing Co.,2 until it closed in 2000. During

the period of its operation, the Plant deposited tons of mercury-

laden waste into the Penobscot River. See Me. People's Alliance,

211 F. Supp. 2d at 253. While there have been a number of other

2
Hanlin Group declared bankruptcy in 1991 and was never named
as a defendant in this action. HoltraChem dissolved in 2001 and,
although originally a party, did not participate in the critical
district court proceedings.

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significant contributors to mercury in the Penobscot, "Mallinckrodt

has been a dominant source." Id. at 255.

In 1986, the Plant's continuous release of mercury led

the Environmental Protection Agency (EPA) to file an administrative

RCRA action against Hanlin (the Plant's quondam owner). That

action resulted in an agreement for corrective measures. Deeming

turnabout fair play, Hanlin sued Mallinckrodt for contribution. In

a 1991 settlement, Mallinckrodt agreed to pay a portion of the

compliance costs imposed by the agreement.

A subsequent enforcement action led to a 1993 consent

decree that superseded the earlier agreement. Although not a party

to this consent decree, Mallinckrodt, consistent with the Hanlin

settlement, paid its share of the compliance costs and participated

in ongoing negotiations with government regulators.3 That included

working with both EPA and Maine's Department of Environmental

Protection (MDEP).

The 1993 consent decree contemplated a tripartite process

comprising site investigation, evaluation of possible corrective

measures, and remediation. In line with the first phase of this

process, Mallinckrodt compiled and submitted a site investigation

report. In March of 1997, EPA and MDEP, acting in concert, issued

3
HoltraChem was involved with Mallinckrodt in much of the
pretrial activity. For ease of exposition, however, we henceforth
will refer to the Plant owners collectively as "Mallinckrodt."
This rhetorical device has no bearing on the outcome of this
appeal.

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a draft notice of disapproval. Mallinckrodt countered with a

supplemental site investigation report but, in 2000, EPA and MDEP

again disapproved. Among other things, the regulators instructed

Mallinckrodt to study the effects of mercury downriver from the

Plant.

Within a matter of months, Mallinckrodt commissioned a

study aimed at examining downriver mercury contamination. It

conducted a second downriver study during the summer of 2001.

Notwithstanding the submission of these studies, however, the

district court supportably found that Mallinckrodt made only

minimal efforts to pursue the designated line of inquiry and that

the decision to forgo more vigorous efforts was deliberate. Id. at

244 & n.9.

In the midst of this sparring, two environmental groups

— the National Resources Defense Council and the Maine People's

Alliance — joined forces to commence a citizen suit under RCRA §

7002(a)(1)(B). The plaintiffs alleged that mercury contamination

downriver from the Plant "may present an imminent and substantial

endangerment to health or the environment." Acknowledging the

possibility that remediation might eventually prove to be either

unnecessary or infeasible, their principal prayer for relief was

that Mallinckrodt be ordered to fund an "independent,

comprehensive, scientific study to determine the precise nature and

extent of the endangerment."

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 Mallinckrodt tried on several occasions to derail the

suit on the ground that EPA, not the courts, had primary

jurisdiction. The district court demurred, holding that the suit

would not present any conflict with agency action due to EPA's

apparent lack of interest in the lower Penobscot.

The case was reached for trial in March of 2002. By that

time, EPA and MDEP had made public, but had not adopted,

preliminary media protection standards, potentially applicable to

the lower Penobscot. Had those standards gone into effect, no

remediation would have been required for the region with which this

litigation is concerned.

During a nine-day bench trial,4 one of the plaintiffs'

principal experts was Dr. Robert Livingston. The district court

found Livingston, an aquatic biologist, to be "particularly

credible and persuasive." Id. at 251. Drawing on three main

sources — the data gathered under the EPA-ordered site studies,

some limited field work, and the scientific literature concerning

mercury in aquatic systems — Livingston opined that there might be

4
We need not recount the trial testimony in endless detail.
The critical facts are laid out in the district court's rescript.
Even though many of the facts are undisputed, the parties have
woven them into widely dissimilar tapestries. On the plaintiffs'
telling, Mallinckrodt is an unrepentant polluter, which
consistently flouted governmental enforcement efforts and finally
wore down the regulators. On Mallinckrodt's telling, the
plaintiffs are overzealous environmentalists attempting an end run
around the reasoned policymaking of an Executive Branch agency.
These pejorative portrayals do little to aid the resolution of the
issues before us.

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a serious endangerment to both human health and the environment

resulting from mercury contamination in the lower Penobscot.

Although believing it "highly likely" that these harms would prove

to be both real and severe, he cautioned that he had not yet "done

the right research to determine that." Due to the absence of

sufficient research, no one could know with certitude "if there is

a problem" or "what the problem is." When all was said and done,

however, he thought it "highly likely" that localized and targeted

remediation would be both necessary and desirable.

The plaintiffs also adduced testimony from other experts,

from individuals within their respective memberships, and from EPA

and MDEP representatives. A number of defense experts testified as

well. After both sides had rested and submitted briefs, the

district court issued a thoughtful rescript.

The court found that mercury in aquatic systems is

susceptible to being transformed by microscopic organisms into its

organic form (known as methylmercury). Id. at 244. Methylmercury

is a highly toxic substance which, even in low dosages, is inimical

to human health; for example, it "attacks the nervous system, the

kidneys, the immune system, and the reproductive system" and is

especially damaging to a developing fetus. Id. at 245.

Methylmercury is especially pernicious because it is the most

bioavailable form of mercury and therefore, is readily accumulated

in humans and animals alike. Id. at 244.

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 Next, the court found that mercury concentration in

sediments extracted from the lower Penobscot runs five times higher

than in the Kennebec River (which Mallinckrodt's expert identified

as an appropriate comparator). Id. at 248. Despite this high

concentration, the court wisely recognized that "the mere presence

of mercury contaminated sediments is alone not enough to constitute

an imminent and substantial endangerment," id., so it proceeded to

examine the available data concerning mercury contamination in

various species in the lower Penobscot, including benthos, killfish

(minnows), lobsters, blue mussels, cormorants, osprey, and eagles.

This examination led the court to conclude that "mercury is

methylating downriver" and that "methylmercury is bioavailable,

entering biota, and biomagnifying throughout the food web." Id. at

251.

The court expressed heightened concern about a region

known as Frankfort Flats, which displayed extraordinarily high

mercury readings in both sediments and biota. Id. at 252.

Frankfort Flats receives drainage from a marsh system, and marshes

are considered to be hotbeds of methylation. See id.

When the district court turned to the legal standard for

citizen suits under RCRA § 7002(a)(1)(B), it characterized that

standard as "lenient." 211 F. Supp. 2d at 246. It cited with

approval case law emphasizing that RCRA allows such a suit when the

putative polluter "may" have caused an imminent and substantial

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endangerment. Id. at 246-47 (collecting cases). On this basis,

the court concluded that the statute's "imminent and substantial

endangerment" standard would be satisfied by a "reasonable medical

concern for public health and a reasonable scientific concern for

the environment." Id. at 252.

Applying this interpretation of the statute to the facts

as found, the court determined that Mallinckrodt's disposal

activities may have created an imminent and substantial danger and

that, therefore, the plaintiffs had carried their burden of proof

anent liability. Id. at 251-52. Then, having found liability, the

court directed the parties to make a good-faith effort to agree on

a study plan. Id. at 256. The parties complied and, on August 10,

2005, the court approved a plan which, if carried out, probably

will require Mallinckrodt to spend around $4,000,000 for laboratory

analyses, independent of all other costs. The purpose of the study

is to learn whether, in actuality, mercury contamination in the

lower Penobscot adversely affects either human health or the

environment, and if so, to devise a feasible remedial approach.

Mallinckrodt now appeals, asserting that the plaintiffs

lacked standing to sue in the first place; that the lower court set

the bar too low for RCRA citizen suits; and that, in all events,

the court abused its discretion in fashioning relief. We address

these assertions one by one.

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II. STANDING

As a threshold matter, Mallinckrodt alleges that the

plaintiffs lack standing to sue because they have not suffered an

injury in fact.5 The existence vel non of standing is a legal

question and, therefore, engenders de novo review. See N.H. Right

to Life Political Action Comm. v. Gardner, 99 F.3d 8, 12 (1st Cir.

1996). When, however, the trial court's standing determination

rests on findings of fact, we must honor those factual findings

unless they are clearly erroneous. See Rivera v. Wyeth-Ayerst

Labs., 283 F.3d 315, 319 (5th Cir. 2002).

We start our inquiry into standing with the undisputed

fact that both of the plaintiffs are associations. In order to

ground a claim of associational standing (that is, standing to

bring suit on behalf of its membership), an association must show

three things: (i) that individual members would have standing to

sue in their own right; (ii) that the interests at stake are

related to the organization's core purposes; and (iii) that both

the asserted claim and the requested relief can be adjudicated

5
Mallinckrodt also makes a weak argument that the claimed
injury cannot be redressed by the relief requested. This argument
focuses on the uncertainty attendant to the study's outcome (for
example, the study may find that there is no endangerment or, if
endangerment exists, that it cannot be rectified). But even in the
absence of a demonstrated need for remediation, the information
that the study will provide is adequate redress because it will
allow the plaintiffs to tailor their behavior to the actual
condition of the lower Penobscot. Consequently, Mallinckrodt's
redressability argument is untenable.

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without the participation of individual members as named

plaintiffs. Friends of the Earth, Inc. v. Laidlaw Envtl. Servs.

(TOC), Inc., 528 U.S. 167, 181 (2000). The plaintiffs in this case

plainly have made the latter two showings. Hence, the inquiry

reduces to whether the organizations' individual members would have

had standing to proceed in their own right.

Because there is nothing in RCRA's text or history that

suggests a congressional intent to erect statutory standing

barriers beyond those imposed by Article III of the Constitution

and because Mallinckrodt has not identified any prudential standing

concerns, we focus on what is essential to establish Article III

standing. Those requirements are expressed in a familiar three-

part algorithm: a would-be plaintiff must demonstrate a concrete

and particularized injury in fact, a causal connection that permits

tracing the claimed injury to the defendant's actions, and a

likelihood that prevailing in the action will afford some redress

for the injury. Lujan v. Defenders of Wildlife, 504 U.S. 555, 560-

61 (1992); Pagán v. Calderón, 448 F.3d 16, 27 (1st Cir. 2006).

These requisites must be proved "with the manner and degree of

evidence required at the successive stages of the litigation."

Lujan, 504 U.S. at 561. When, as now, standing is reviewed after

trial, the facts establishing standing "must be supported

adequately by the evidence adduced at trial." Id. (internal

quotation marks omitted). The ultimate quotient of proof is a

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preponderance of the evidence. See Perry v. Vill. of Arlington

Heights, 186 F.3d 826, 829 (7th Cir. 1999).

We first dispose of an argument that verges on the

specious. Mallinckrodt protests that the plaintiffs cannot have

established a cognizable injury since the district court thought it

appropriate to order a remedy — the study — that would determine

whether mercury in the Penobscot is "having significant adverse

effects" on the environment or "posing an unacceptable risk to

human health." This protestation conflates the district court's

finding of liability with its choice of remedy. As we shortly

shall explain, probabilistic harms are legally cognizable, and the

district court made a supportable finding that a sufficient

probability of harm exists to satisfy the Article III standing

inquiry. See Me. People's Alliance, 211 F. Supp. 2d at 253. The

fact that the court chose a remedy that aspires to furnish a degree

of determinacy before fashioning further relief speaks only to the

court's cautious use of discretion in selecting remedies; it does

not speak to the plaintiffs' standing as of the present time.

Having dispatched this attempted sleight of hand, we

proceed to more serious matters. Mallinckrodt concentrates its

standing attack on the plaintiffs' ostensible failure to prove the

injury-in-fact component. At trial, the plaintiffs called four

witnesses from within their respective memberships, all of whom

reside on or near the banks of the Penobscot River. All four

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vouchsafed that they have modified their behavior due to fear of

mercury contamination. Although eager to do so, none of them will

eat fish or shellfish from the river nor recreate on or near it.

One witness added that, but for the mercury contamination, she

would harvest mussels and sell them to supplement her income. The

district court credited this testimony. Id.

Plaintiffs in environmental suits may predicate claims of

injury on aesthetic or recreational harms. See Laidlaw, 528 U.S.

at 183; Sierra Club v. Morton, 405 U.S. 727, 735 (1972); Save Our

Heritage, Inc. v. FAA, 269 F.3d 49, 55 (1st Cir. 2001). Still,

neither a bald assertion of such a harm nor a purely subjective

fear that an environmental hazard may have been created is enough

to ground standing. Rather, an individual's decision to deny

herself aesthetic or recreational pleasures based on concern about

pollution will constitute a cognizable injury only when the concern

is premised upon a realistic threat. See Laidlaw, 528 U.S. at 184;

see also City of Los Angeles v. Lyons, 461 U.S. 95, 107 n.8 (1983)

(explaining that "the reality of the threat . . . , not the

plaintiff's subjective apprehensions," constitutes the cognizable

injury).

In this instance, Mallinckrodt exhorts us to find that

the witnesses' stated fears are unreasonable. It points out — and

the record confirms — that waterways throughout Maine suffer to

some extent from mercury pollution and that, therefore, it is

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responsible at most for a probabilistic increase in a risk that the

witnesses would in any event have had to run.

There is some confusion as to the thrust of

Mallinckrodt's argument. The plaintiffs read its brief, not

implausibly, as arguing that these facts necessarily limit

cognizable injuries to identifiable medical concerns. See

Appellees' Br. at 54. Mallinckrodt's reply brief, however,

acknowledges that the plaintiffs' principal claim of injury is for

diminished enjoyment of their environment and joins issue on the

sufficiency of the proof in that regard. See Appellant's Reply Br.

at 25. At bottom, this argument suggests that the plaintiffs must

show that Mallinckrodt's activities created a significantly

increased risk of harm to health or the environment so as to make

it objectively reasonable for the plaintiffs' members to deny

themselves aesthetic and recreational use of the river.

To establish an injury in fact based on a probabilistic

harm, a plaintiff must show that there is a substantial probability

that harm will occur. See Warth v. Seldin, 422 U.S. 490, 504

(1975); see also Adams v. Watson, 10 F.3d 915, 923 (1st Cir. 1993).

Mallinckrodt suggests that the instant plaintiffs have not

demonstrated a sufficiently probable increase in harm because of

(i) Dr. Livingston's admitted uncertainty about whether any problem

exists and (ii) the notion that politically accountable branches of

government, not courts, are the appropriate entities to make

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judgments as to what risks are acceptable in modern society.

Neither suggestion is convincing.

Mallinckrodt's first suggestion relies ultimately on a

single snippet of Dr. Livingston's testimony, wrested from its

contextual moorings. But a trial court, confronted with a complex

and highly ramified factual situation, is fully entitled to

consider the import of a witness's testimony as a whole. This case

is a good example: Dr. Livingston testified, in effect, that the

presence of a great deal of smoke justified looking for a fire.

Mallinckrodt excerpts only his isolated statement that he had not

actually seen a fire yet. This plucking of the record overlooks

the obvious fact that the district court, drawing on the whole of

Dr. Livingston's testimony as well as a plethora of other evidence,

supportably concluded that "mercury is methylating downriver, and

that such methylmercury is bioavailable, entering biota, and

biomagnifying throughout the food web" in sufficient quantity that

it may well present an imminent and substantial danger to the

environment. Me. People's Alliance, 211 F. Supp. 2d at 251

(citation omitted). Relatedly, the court found that "the effects

resulting from methylmercury exposure . . . clearly endanger

reproduction, development, and overall health of the public and the

environment," id. at 252, and that "Mallinckrodt has been a

dominant source of mercury in the Penobscot River," id. at 255.

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 In other words — to return to our metaphor — the lower

court discerned telltale signs that a fire might already be

smoldering. In light of its warrantable findings, the court had

ample reason to conclude that Mallinckrodt has created a

substantial probability of increased harm to the environment. That

increased risk, in turn, rendered reasonable the actions of the

plaintiffs' members in abstaining from their desired enjoyment of

the Penobscot.

Mallinckrodt's second suggestion is nothing less than a

no-holds-barred assault on the federal courts' institutional

competency. It emphasizes that the plaintiffs allege no violation

of any federally prescribed discharge limits, and then treats this

omission as dispositive. See Appellant's Br. at 27 (asserting that

"in the absence of any finding by [EPA]," courts are not equipped

to determine whether "the medical and scientific uncertainties

created by mercury in the Penobscot create an unacceptable

increased risk of harm" (emphasis in original)).

This postulate proceeds from a two-part premise. First,

in terms of environmental regulation — where important policy

tradeoffs must be made between protection and progress — the only

injuries that satisfy the criteria for Article III standing are

those injuries that are "unacceptable"; and second, the political

branches alone, not courts, have the expertise and accountability

to determine which injuries society must be prepared to tolerate.

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In Mallinckrodt's view, this need to restrict cognizable injuries

to "unacceptable" injuries is especially acute where, as in this

case, the asserted harms are probabilistic.

Mallinckrodt provides scant authority for an argument

that has such breathtaking ramifications for the scope of judicial

power. Its notion of acceptability is apparently derived from a

single, quarter-century-old opinion, in which a respected court

cautioned that judges cannot "formulate policy with respect to what

[environmental] risks are acceptable." Envtl. Def. Fund v. EPA,

598 F.2d 62, 83-84 (D.C. Cir. 1978). That court, however, was

reviewing a challenge to an EPA regulation based on an alleged lack

of substantial evidence. There is no discussion either of standing

or of Article III's limits on judicial power. The opinion,

therefore, affords no solid foundation for the proposition that

Mallinckrodt asserts.6

In a related vein, Mallinckrodt argues that a grant of

standing in this case would be tantamount to judicial usurpation of

regulatory authority because it would permit "private parties to

attack EPA risk assessments collaterally, using the very risks EPA

deemed acceptable to establish standing and liability, with no

deference afforded to EPA's policy judgment." Appellant's Reply

6
Mallinckrodt's other citations — National Lime Ass'n v. EPA,
627 F.2d 416, 433 n.48 (D.C. Cir. 1980), and Industrial Union
Department v. American Petroleum Institute, 448 U.S. 607, 662-63
(1980) (Burger, C.J., concurring) — likewise concern judicial
review of agency regulations. They too are inapposite.

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Br. at 27-28. But the ingredients that comprise what Mallinckrodt

sees as a recipe for disaster — the relatively broad scope of

citizens' rights to sue polluters, the existence of liability in

such suits, and the less-than-total deference afforded to agency

inaction — all turn on legislative choices. Congress has elected

to create a cause of action for affected citizens notwithstanding

the absence of any EPA-sponsored standard. While we share

Mallinckrodt's belief that it would be a usurpation of legislative

prerogative for a court to assume policymaking control over

environmental regulation, it would be no less offensive a

usurpation for a court to refuse to undertake a task validly

entrusted to it by Congress. In the last analysis, Article III

requires a cognizable injury; it does not speak to the wisdom of

the legislature's actions in providing redress for that injury.

We add an eschatocol of sorts. In rejecting

Mallinckrodt's arguments as to standing, we remain confident that

Congress has not asked federal courts to perform tasks that are

beyond their institutional competency. In our view, courts are

capable of assessing probabilistic injuries. Moreover, nuisance

principles contribute heavily to the doctrinal template that

underbraces statutes like RCRA, see, e.g., Cox v. City of Dallas,

256 F.3d 281, 289 (5th Cir. 2001), and the tasks involved in

adjudicating environmental cases are well within the federal

courts' accustomed domain. While courts can (and do) benefit from

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available agency expertise, it is an insupportable leap of logic to

maintain that, in the absence of such input, claims of injury are

not cognizable at all.

That ends this aspect of the matter. For the reasons

discussed above, we hold that the plaintiffs have standing to sue

under RCRA § 7002(a)(1)(B). We turn, then, to the meat of the

appeal.

III. THE MERITS

This case revolves around the meaning and purport of RCRA

§ 7002(a)(1)(B), a statute that, as described above, allows

citizens to sue persons or firms whose handling of solid or

hazardous waste "may present an imminent and substantial

endangerment to health or the environment." Id. The district

court read this language as meaning that such suits could be

brought to alleviate reasonable medical or scientific concerns.

Me. People's Alliance, 211 F. Supp. 2d at 252. Mallinckrodt urges

a more circumscribed interpretation. To the extent that this

interpretive controversy presents a question of statutory

construction, we afford de novo review.7 See Lattab v. Ashcroft,

384 F.3d 8, 21 (1st Cir. 2004).

7
Mallinckrodt has pitched this aspect of its appeal
exclusively in terms of statutory construction. Had it challenged
the district court's application of the law to the facts, our
review would have been more deferential. See, e.g., Interfaith
Cmty. Org. v. Honeywell Int'l, Inc., 399 F.3d 248, 254 (3d Cir.
2005) (advocating "clear error" review).

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 An historical perspective illustrates the strength of the

current against which Mallinckrodt is swimming. Congress enacted

RCRA in 1976, Pub. L. No. 94-580, 90 Stat. 2795, with the avowed

intention of closing "the last remaining loophole in environmental

law, that of unregulated land disposal of discarded materials and

hazardous waste." H.R. Rep. No. 94-1491, pt. 1, at 4, reprinted in

1976 U.S.C.C.A.N. 6238, 6241. In its original iteration, RCRA §

7002 (now codified in pertinent part at 42 U.S.C. § 6972(a)(1)(A))

offered citizens the opportunity to bring suit against a polluter

only when the polluter was alleged to be in violation of a permit,

standard, regulation, condition, requirement, or order issued by

EPA. At the same time, RCRA created a cause of action, available

exclusively to the EPA Administrator, for cases in which the

"disposal of any solid waste or hazardous waste is presenting an

imminent and substantial endangerment to health or the

environment." RCRA § 7003 (codified as amended at 42 U.S.C. §

6973(a)). In suits brought under this latter provision, federal

district courts were granted broad remedial authority to "restrain"

polluters and take "such other action as may be necessary." Id.

Pertinently we think, Congress later loosened the

standard for liability under section 7003. This transpired four

years later when Congress passed the Solid Waste Disposal Act

Amendments of 1980. That legislation amended section 7003 by

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substituting the words "may present" for the words "is presenting."

Pub. L. No. 96-482, § 25, 94 Stat. 2334, 2348.

In United States v. Price, 688 F.2d 204 (3d Cir. 1982),

a seminal RCRA § 7003 case, a district court found that a landfill

leaking toxic substances posed an imminent and substantial danger

to Atlantic City's water supply but refused to order a study of

this hazard at the preliminary injunction stage. Id. at 209. The

Third Circuit reversed, ruling that the use of the word "may" in

RCRA § 7003 was intended to make the provision "expansive." Id. at

213. In its view, "Congress, by enacting section 7003, intended to

confer upon courts the authority to grant affirmative equitable

relief to the extent necessary to eliminate any risks posed by

toxic waste." Id. at 214.

Soon thereafter, Congress passed the Hazardous and Solid

Waste Amendments of 1984 (1984 amendments), Pub. L. No. 98-616, 98

Stat. 3221. The 1984 amendments introduced a new provision, RCRA

§ 7002(a)(1)(B), into the statutory scheme. Using language that

tracked the post-1980 text of RCRA § 7003, this new provision

extended to citizens the right to sue a polluter who may be causing

an imminent and substantial endangerment to public health or the

environment. Id. § 401, 98 Stat. at 3268-69. The Senate Report

that accompanied the 1984 amendments approvingly cited and quoted

Price on several occasions, specifically endorsing that court's

conclusion that section 7003 is intended to give courts the tools

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to "eliminate any risks posed by toxic waste." S. Rep. No. 98-284,

at 59 (1983).

Around this same time, the Fourth Circuit decided another

RCRA § 7003 case, in which it flatly rejected the proposition that

"section 7003 was designed to control pollution only in emergency

situations." United States v. Waste Indus., Inc., 734 F.2d 159,

165 (4th Cir. 1984). The court emphasized the statute's use of the

word "may" and cited Price approvingly.

Price and Waste Industries have become guideposts for

courts endeavoring to interpret the counterpart language contained

in RCRA § 7002(a)(1)(B). To date, at least four of our sister

circuits have construed that provision expansively. See Interfaith

Cmty. Org. v. Honeywell Int'l., Inc., 399 F.3d 248, 258-59 (3d Cir.

2005); Parker v. Scrap Metal Processors, Inc., 386 F.3d 993, 1015

(11th Cir. 2004); Cox, 256 F.3d at 299; Dague v. City of

Burlington, 935 F.2d 1343, 1355 (2d Cir. 1991), rev'd in part on

other grounds, 505 U.S. 557 (1992). In taking this position, all

four courts have emphasized the preeminence of the word "may" in

defining the degree of risk needed to support RCRA §

7002(a)(1)(B)'s liability standard.

This expansiveness in construing the requisite degree of

risk has largely been matched in the courts' assessment of the

gravity and immediacy of the threatened harm. With one possible

exception, the courts have agreed that the word "substantial"

-22-
implies serious harm.8 See, e.g., Parker, 386 F.3d at 1015. There

has, however, been some reluctance to quantify the needed level of

harm more precisely. See, e.g., Honeywell, 399 F.3d at 259.

Imminence generally has been read to require only that the harm is

of a kind that poses a near-term threat; there is no corollary

requirement that the harm necessarily will occur or that the actual

damage will manifest itself immediately. See Cox, 256 F.3d at 299-

300.

Mallinckrodt argues that this long line of cases has

consistently misread Price (which, Mallinckrodt says, only

concerned remedial power, not scope of liability) and, in the

bargain, has disregarded the strictures imposed by the adjectives

"imminent" and "substantial." We have not had occasion to construe

the reach of the citizen suit provision contained in RCRA §

7002(a)(1)(B), and we are obligated to offer our independent

judgment on an issue of first impression here (which, as we shortly

shall explain, coincides with the result reached by the other

courts of appeals that have confronted the question). Accordingly,

we proceed to test the mettle of the conventional construction of

RCRA § 7002(a)(1)(B) against Mallinckrodt's challenge.

The district court, following the interpretive trail

blazed by the four above-mentioned courts of appeals, employed the

8
The possible exception is the Second Circuit, which, to date,
has not committed to read into the statute a requirement of
seriousness. See Dague, 935 F.2d at 1355-56.

-23-
conventional construction. It began by noting that the word

"endangerment" does not imply actual harm but, rather, implies only

potential harm. Me. People's Alliance, 211 F. Supp. 2d at 246.

The court then noted that the statutory standard is further relaxed

because of Congress's use of the word "may." Id. As a result, the

court found RCRA § 7002(a)(1)(B) to be a "sweeping provision

indicat[ing] Congress's intent 'to confer upon the courts the

authority to grant affirmative equitable relief to the extent

necessary to eliminate any risk posed by toxic waste.'" Id. at

246-47 (quoting Dague, 935 F.2d at 1355 (quoting Price, 688 F.2d at

214) (emphasis supplied in Dague)).

The court read the statute's adjectival elements in line

with the breadth of the authority granted. It found that the word

"imminent" connotes only that the "factors giving rise to [the

harm] are present, even though the harm may not be realized for

some time." Id. at 247. Relatedly, the court found that the word

"substantial" connotes no more than "reasonable cause for concern

that someone or something may be exposed" to harm. Id. (quoting

Raymond K. Hoxsie Real Estate Trust v. Exxon Educ. Found., 81 F.

Supp. 2d 359, 366 (D.R.I. 2000) (internal quotation marks

omitted)). A "reasonable medical concern" would, the court said,

be sufficient to ground liability under the statute. Id. at 252.

The court's only explicit limitation on the availability of relief

was when "the risk of harm is remote in time, completely

-24-
speculative in nature, or de minimis in degree." Id. at 247

(quoting United States v. Reilly Tar & Chem. Corp., 546 F. Supp.

1100, 1109 (D. Minn. 1982)). Mallinckrodt balks at this

interpretation of RCRA § 7002(a)(1)(B) for a host of reasons. It

argues that this construction ignores the plain meaning of the

phrase "imminent and substantial endangerment," does violence to

the internal coherence of RCRA by overlooking the hierarchy of

standards contained within that statute, tampers with Congress's

wise delegation of policymaking to an expert agency, and frustrates

congressional intent. We address each of these criticisms in turn.

Mallinckrodt's textual argument rests on the premise that

the courts that heretofore have explicated section 7002(a)(1)(B)'s

liability standard have been blinded by the glare of the word "may"

and have lost sight of the plain meaning of the words "imminent and

substantial." In Mallinckrodt's view, the phrase "may present an

imminent and substantial endangerment," when read as a whole,

requires a risk of grave harm that is more likely than not to

occur. Mallinckrodt deduces this construction from a Rosetta Stone

that is part case law and part lexicography.

The word "endangerment," Mallinckrodt says somewhat

tautologically, is "the state of being placed in danger." Webster's

Third New International Dictionary 748 (1993). In that connection,

it defines danger as "exposed to harm" or "peril." Id. at 573

(excess capitalization omitted). To elucidate the meaning of "may,"

-25-
Mallinckrodt points to a sixty-year old Supreme Court decision that

defines "may," as used in section 2(a) of the Clayton Act, as

"probably." Corn Prods. Refining Co. v. FTC, 324 U.S. 726, 738

(1945). Finally, to give content to the phrase "imminent and

substantial," Mallinckrodt invokes case law suggesting that, in

other environmental contexts, the unadorned word "endanger" implies

a lower standard than that denoted by the phrase "imminent and

substantial endangerment." See Ethyl Corp. v. EPA, 541 F.2d 1, 20

n.36 (D.C. Cir. 1976) (en banc); Reserve Mining Co. v. EPA, 514 F.2d

492, 528 (8th Cir. 1975) (en banc).

Mallinckrodt's textual argument makes sense — but only to

a point. While the decisions in Ethyl Corp. and Reserve Mining are

some evidence that, as of 1976, the phrase "imminent and substantial

endangerment" was thought to denote a heightened standard,9 the

relevant question is how that term was understood in 1984 (when

section 7002(a)(1)(B) was enacted). The Senate Report on the 1984

amendments defines the word "endangerment" separately from the

phrase "imminent and substantial." See S. Rep. No. 98-284, supra,

at 59. Mallinckrodt's criticism fails to account either for that

circumstance or for Congress's insertion, in 1980, of the word "may"

9
Mallinckrodt is correct in noting that the district court,
which cited both Ethyl Corp. and Reserve Mining, see Me. People's
Alliance, 211 F. Supp. 2d at 246, failed to acknowledge that those
cases were defining the term "endangerment" in contrast with
"imminent and substantial endangerment." This observation may
weaken the persuasive power of the district court's reasoning, but
it hardly answers the definitional question.

-26-
into section 7003 and its subsequent use in section 7002. That word

does not appear at all in the statute considered in Reserve Mining,

514 F.2d at 528 & n.70 (citing 33 U.S.C. § 1364). In Ethyl Corp.,

one of the referenced statutes does use the word "may," but that

court did not parse the entire sentence and looked only to the words

"imminent and substantial." See Ethyl Corp., 541 F.2d at 20 n.36

(citing 42 U.S.C. § 300i). We also note that statutes referenced

in Ethyl Corp. and Reserve Mining bore the subtitle "Emergency

Powers"; in contrast, neither section 7002 nor section 7003 carry

such a label.

The sockdolager, we think, is that "words are like

chameleons; they frequently have different shades of meaning

depending upon the circumstances." United States v. Romain, 393

F.3d 63, 74 (1st Cir. 2004). The terrain of the Clayton Act and

provisions specifically classified as conferring emergency powers

are sufficiently distinct in subject matter from RCRA's terrain.

Thus, we are unprepared to say that the nuances attached to the

phrase "may present an imminent and substantial endangerment" by

judicial decisions in those other contexts should be transplanted

root and branch into the differently textured soil of RCRA §

7002(a)(1)(B) — a statute enacted by a different Congress at a

different time for a different purpose. We conclude, therefore,

that Mallinckrodt's textual argument does not carry the day: the

-27-
interpretive question before us cannot be resolved favorably to

Mallinckrodt on the basis of plain meaning alone.

Mallinckrodt next argues that the conventional

interpretation of section 7002(a)(1)(B) drains the phrase "imminent

and substantial" of any meaning because RCRA already defines

"hazardous waste" as material that will cause an increase in

mortality or serious illness or "pose a substantial present or

potential hazard to human health or the environment." 42 U.S.C. §

6903(5). Thus, any release of hazardous waste would satisfy the

conventional construction of RCRA § 7002(a)(1)(B), and the

requirement that such a release create an "imminent and substantial

endangerment" would be superfluous.

This argument is easily dispatched. In terms, section

7002(a)(1)(B) applies to both solid waste and hazardous waste.

RCRA's definition of "solid waste" does not share the same

characteristics as its definition of "hazardous waste," so to that

extent the phrase "imminent and substantial" retains an independent

meaning.

Relatedly, Mallinckrodt asserts that the conventional

interpretation of "imminent and substantial endangerment" overlooks

RCRA's commitment to a hierarchy of risks in which "imminent and

substantial endangerment" ranks at or near the top. This argument

builds on the idea that Congress employed relatively lenient risk

standards elsewhere in RCRA. See, e.g., RCRA § 4004(a), codified

-28-
at 42 U.S.C. § 6944(a) (providing that sanitary landfills must have

"no reasonable probability of adverse effects on health or the

environment"). Correspondingly, the word "endangerment" is used in

other contexts in connection with "imminent danger of death or

serious bodily injury." See, e.g., RCRA § 3008(e), codified at 42

U.S.C. § 6928(e) (defining the crime of "knowing endangerment").

Thus, the decision to require an "imminent and substantial

endangerment" must signify a special, harder-to-achieve benchmark.

This argument has some superficial appeal. After all, it

is a cardinal rule that courts should strive to interpret statutes

as a whole and to give effect to every word and phrase. King v. St.

Vincent Hosp., 502 U.S. 215, 221 (1991); United States v. Ven-Fuel,

Inc., 758 F.2d 741, 751-52 (1st Cir. 1985). But the conventional

interpretation of section 7002(a)(1)(B) gives full effect to the

"imminent and substantial endangerment" language; it merely eschews

the mechanical cross-referencing, not mandated by Congress, that

Mallinckrodt advocates. That, in itself, should not raise eyebrows:

where the various parts of a complicated and multifaceted statutory

scheme discuss significantly different topics and function within

different paradigms, mechanical cross-referencing, not mandated by

Congress, can lead to confusion rather than clarity.

This is such a case. There is no meaningful parallelism

between section 7002(a)(1)(B) and the provisions that Mallinckrodt

seeks to use as comparators. For example, RCRA § 3008(e) is a

-29-
criminal provision. Given the divergent concerns that drive

criminal statutes as opposed to civil remedial statutes, it should

not be surprising that the same word may vary in meaning as the

context shifts. Indeed, if "endangerment" as defined in section

3008(e) were to mean precisely what it means in section

7002(a)(1)(B), the word "imminent" would be rendered utterly

redundant — the statute would, in effect, require an imminent

imminence — thus transgressing the very canon of construction that

Mallinckrodt labors to invoke.

Mallinckrodt offers a more sophisticated version of the

argument that RCRA creates a hierarchy of risks when it posits that

the statute's most expansive remedies are reserved for the greatest

risks. In this regard, it points out that under RCRA § 3019(b), EPA

can commission a health assessment whenever it believes that a

landfill "poses a substantial potential risk to human health," 42

U.S.C. § 6939a(b); under RCRA § 3013, EPA can order the owner or

operator of a facility to conduct monitoring, testing, and analysis

as long as the facility "may present a substantial hazard to human

health or the environment," id. § 6934(a); and under RCRA § 7003,

which has a risk standard identical to RCRA § 7002(a)(1)(B), EPA can

act to protect the public health, see id. § 6973(a). From this

statutory melange, Mallinckrodt concludes that only the immediate

threat of grave harm is sufficient to trigger such far-reaching

remedies.

-30-
 The notion that a hierarchy of risks and remedies exists

within RCRA is not easily disproved. What is fairly clear, however,

is that any such hierarchy is well-disguised; if one exists, it

seems more a product of fortuity than a product of a purposeful

legislative initiative. We explain briefly.

Section 3019(b) was first enacted in 1984, Pub. L. No.

98-616, § 247, 98 Stat. 3221, 3265; section 3013 in 1980, Pub. L.

No. 96-482, § 17(a), 94 Stat. 2334, 2344; and section 7003

(previously cited) in 1976 (though that provision was amended both

in 1980 and 1984). Given that the changes were made to different

subtitles of the statute at different times, such incrementalism

weakens (perhaps to the vanishing point) any inference that Congress

specifically intended a strict hierarchy of harms. If Congress

actually wants a delineated hierarchy of risks and remedies, it will

have to say so more distinctly. Cf. King, 502 U.S. at 222

(construing that "differences do not necessarily make hierarchies").

This brings us to Mallinckrodt's separation-of-powers

argument. It asseverates that RCRA's allocation of policymaking

authority to EPA is such that the citizen suit provision must be

viewed as an "interstitial, emergency-type remedy." Appellant's Br.

at 45. Mallinckrodt asserts that this policymaking authority

necessarily includes responsibility for setting pollution standards

and that, in setting such standards, EPA, consistent with the

-31-
tradeoffs inherent in setting virtually any standard, does not

aspire to eliminate all risks.

This assertion is founded on an indisputable verity: the

principal responsibility for implementing and enforcing RCRA resides

with EPA, not with citizens acting as private attorneys general.

See Meghrig v. KFC Western, Inc., 516 U.S. 479, 483-84 (1996). We

disagree, however, with Mallinckrodt's contention that the

conventional interpretation of section 7002(a)(1)(B) — the

interpretation espoused by our sister circuits and by the court

below — is inconsistent with this scheme because it allows courts

to second-guess EPA's judgments too freely and affords relief based

upon harms that EPA has found acceptable.

Mallinckrodt attempts to bolster this argument by citing

a plethora of cases for the proposition that environmental standards

should be set by EPA, not the courts. See, e.g., Amoco Oil Co. v.

EPA, 501 F.2d 722, 735 (D.C. Cir. 1974). This proposition is

unremarkable, and we take no issue with it. We agree, moreover,

that courts must show appropriate respect for EPA's judgments. See

Envtl. Def. Fund, 598 F.2d at 83-84. But allowing citizen suits to

proceed is not the functional equivalent of allowing courts to

hijack EPA's regulatory authority and weave safety standards out of

whole cloth.

The case at hand illustrates this point. Although EPA

(acting in concert with MDEP) was leaning toward the adoption of

-32-
media protection standards that would not have required downriver

remediation, no standards had been adopted at the time the district

court acted (nor, for that matter, does the record suggest that any

have been adopted up to the present time). Furthermore, EPA has

never taken the position — or even so much as hinted — that

correction of the Plant's effects on downriver pollution is bad

policy. Thus, this is not a situation in which a court has presumed

to grant relief that flies in the face of an express EPA

authorization of certain conduct.

We add, moreover, that the district court has been

sensitive to separation-of-powers concerns. On three different

occasions, it considered and thoughtfully rejected primary

jurisdiction challenges.10 And the court sensibly left open the

possibility that "primary jurisdiction concerns could arise in the

future." Me. People's Alliance, 211 F. Supp. 2d at 255. That

presumably would cover the contingency of changed circumstances that

would eventuate should EPA, some day, actually engage in an

enforcement action pertinent to the condition of the lower

Penobscot.

The fact that courts retain some latitude in this area is

not in any sense incompatible with the statutory scheme. There are

four different ways that EPA can preempt a citizen suit — and all

10
Mallinckrodt has opted not to revisit the district court's
rejection of these challenges in this appeal.

-33-
four require that EPA itself take diligent steps to remedy looming

environmental harm. See RCRA § 7002(b)(2)(B) (codified at 42 U.S.C.

§ 6972(b)(2)(B)). That same provision narrowly circumscribes EPA's

preemptive power; it states that, when preemption is premised on an

EPA order, citizen suits are "prohibited only as to the scope and

duration of the administrative order." The short of it is that

Congress has told the federal courts that they are not required to

steer clear of an area simply because that area might be a focus of

future EPA activity.11

Mallinckrodt tries to embellish its separation-of-powers

argument in another way as well; it maintains that section 7002(a)

embodies a strong preference for permit-violation suits as opposed

to imminent and substantial endangerment suits. This attempted

embellishment does not withstand scrutiny.

When not premised on the title related to hazardous

waste, a permit-violation suit may be brought after a 60-day waiting

period while an imminent and substantial endangerment suit requires

observance of a 90-day waiting period. Compare RCRA § 7002(b)(1)

(codified at 42 U.S.C. § 6972(b)(1)), with RCRA § 7002(b)(2)

(codified at § 6972(b)(2)). This is the only substantive difference

between permit-violation suits and suits alleging imminent and

11
This is not meant to suggest that a private party can
interfere with an EPA prosecution or disturb the finality of a
negotiated settlement. The opposite is true. See Supporters to
Oppose Pollution, Inc. v. Heritage Group, 973 F.2d 1320, 1323-25
(7th Cir. 1992).

-34-
substantial endangerment. Given the relatively minor nature of that

lone disparity, we conclude, without serious question, that the

structure of the statutory scheme does not offer any persuasive

evidence that Congress sought to disfavor suits alleging imminent

and substantial endangerment.

Mallinckrodt's emphasis on statutory structure includes

an assertion that giving section 7002(a)(1)(B) a broad reading will

render nugatory the right to bring permit-violation actions and the

like under RCRA § 7002(a)(1)(A). See Appellant's Reply Br. at 15-16

(querying whether, if "there is a big hole in a fence for the big

cat, need there be a small one for the small one?") (citation and

internal quotation marks omitted)). The flaw in this argument, as

it pertains to this case, is that the two holes were drilled at

different times. Congress placed the "imminent and substantial

endangerment" gloss on RCRA's citizen suit provision eight years

after making provision for permit-violation suits. Thus, the more

appropriate question is: "If Congress deliberately cut a second hole

in the fence, is there any reason not to accept the obvious premise

that Congress wanted to increase the ease with which cats of all

sizes could come through the fence?"

Insofar as Mallinckrodt theorizes that courts lack the

competence to function under the conventional interpretation of RCRA

§ 7002(a)(1)(B), we reject its thesis. To be sure, Mallinckrodt

cites case after case for the proposition that forging policy is a

-35-
task that non-expert, non-accountable judges should not undertake.

See, e.g., Chevron U.S.A., Inc. v. Natural Res. Def. Council, Inc.,

467 U.S. 837, 866 (1984); United States v. Gilman, 347 U.S. 507,

511-13 (1954). Some of these cases suggest that judicial

policymaking in the environmental sphere is especially inappropriate

because judges lack special competence to interpret complex

scientific, technical, and medical data. See, e.g., Safe Food &

Fertil. v. EPA, 365 F.3d 46, 49 (D.C. Cir. 2004).

This view sells the federal judiciary short: federal

courts have proven, over time, that they are equipped to adjudicate

individual cases, regardless of the complexity of the issues

involved. Federal courts are often called upon to make evaluative

judgments in highly technical areas (patent litigation is an

excellent example).12 Performing that quintessentially judicial

function in the environmental sphere is not tantamount to rewriting

environmental policy. To the contrary, what the lower court did

here — listening to the testimony of expert witnesses, assessing

their credibility, and determining whether or not a litigant has

carried the devoir of persuasion — is very much within the core

competency of a federal district court.

12
Indeed, even on Mallinckrodt's crabbed interpretation of
section 7002(a)(1)(B), courts would have to engage in exactly the
type of evidence-weighing that Mallinckrodt says is beyond their
competence.

-36-
 As a last-ditch measure, Mallinckrodt strives to convince

us that Congress's revealed intent, as reflected in the legislative

history, counsels in favor of a narrow reading of section

7002(a)(1)(B). We are not persuaded.

The argument shapes up along the following lines. Citing

S. Rep. No. 98-284, supra, at 56, Mallinckrodt reads this archival

information as confirming that section 7002(a)(1)(B) was intended

to operate "exactly the same" as section 7003. Building on that

foundation, Mallinckrodt notes that section 7003, when enacted in

1976, was envisioned as a means of providing "emergency authority."

S. Rep. No. 94-988, at 16 (1976). This gloss, though artful, mixes

plums and pomegranates.

What is relevant to a congressional statement, in 1984,

that section 7002(a)(1)(B) is intended to operate in the same way

as section 7003, is not how Congress viewed section 7003 at the time

of its original passage but, rather, how Congress understood section

7003 in 1984. This is especially significant because section 7003

was not worded the same in 1984 as it was in 1976. We think it is

clear that the 1980 amendment to the provision, substituting "may

present" for "is presenting," fundamentally altered how this

provision was understood.

The proof of the pudding is in the legislative archives.

We refer particularly to the way in which the provision was

-37-
discussed during testimony taken in anticipation of the 1984

amendments.

At that time, the House of Representatives was told

authoritatively that section 7003 contained "very broad and general

statutory language" and that the government, "over the last several

years," had been advocating "as broad an interpretation [of it] as

possible." Solid Waste Disposal Act Amendments of 1983: Hearing on

S. 757 Before the Subcomm. on Envtl. Pollution of the S. Comm. on

Env't and Public Works, 98th Cong. 17, 29 (1983) (statement of Carol

Dinkins, Asst. Atty. Gen., Land and Nat. Res. Div., Dep't of

Justice). It also learned that the Department of Justice viewed

section 7003 as "loosely worded," so that it conveyed

"extraordinary, broad law enforcement powers." Id. at 110, 120.

The Senate's discussion of section 7003 in the course of

considering the 1984 amendments likewise suggests an expansive view

of the provision. The Senate Report enthusiastically quotes Price

for the proposition that section 7003 is "intended to confer upon

the courts the authority to grant affirmative equitable relief to

the extent necessary to eliminate any risks posed by toxic

wastes."13 S. Rep. No. 98-284, supra, at 59 (quoting Price, 688

13
Mallinckrodt's major criticism of the courts that have relied
upon Price when construing section 7002(a)(1)(B) is that liability
was not contested in Price and that, therefore, the quoted language
must have referred to remedial authority. This criticism is
undercut by the fact that the Senate Report quotes Price when
discussing the liability standard.

-38-
F.2d at 214). It went on to observe that the "primary intent of the

provision is to protect human health and the environment." Id.

Thus, there is good reason to believe that Congress, intending to

create a provision modeled along the lines of section 7003,

understood that section as offering much more than emergency

authority.

The legislative history is also at odds with

Mallinckrodt's argument that the conventional interpretation of

section 7002(a)(1)(B) usurps EPA's policymaking role. In parsing

this legislative history, it is important to recognize that

Congress, in 1984, was acting against a background finding that

there were "serious gaps" in RCRA, that EPA's enforcement actions

were characterized by "inadequate effort," and that EPA "ha[d] not

been diligent in vigorously pursuing a tough enforcement program."

H.R. Rep. No. 98-198, pt. 1, at 20 (1983), reprinted in 1984

U.S.C.C.A.N. 5576, 5578-79. Congress had heard, and apparently

credited, testimony from a former Assistant Attorney General about

"an astonishing two years of mismanagement at EPA in which the

enforcement of the hazardous waste disposal laws suffered greatly."

Id., pt. 3, at 6, reprinted in 1984 U.S.C.C.A.N. 5636, 5641. Given

this mise-en-scène, it seems counterintuitive to suggest that

Congress intended to erect an enforcement structure built on

exaggerated deference to EPA.

-39-
 To be sure, the legislative history reflects the

anticipation that "courts will accord some deference to [EPA's]

technical findings concerning the nature and extent of

endangerment." S. Rep. No. 98-284, supra, at 56. But we do not

think that "some deference" means either total obeisance or blind

allegiance. Congress desired a "tough enforcement program" and

found that EPA had not been "diligent in vigorously pursuing" one.

Citizen suits were meant to fill the resultant void.14

We are unimpressed by Mallinckrodt's citation to language

in the House Report to the effect that section 7002(a)(1)(B) was

designed to create a "limited right" for citizens to sue. H.R. Rep.

No. 98-198, supra, pt. 1, at 53, 1984 U.S.C.C.A.N. at 5612. The

very next sentence in that report explains the nature of the

limitation, namely, that this "right can only be exercised if the

Administrator (following notice of the intended litigation) fails

to file an action under 7003." Id. The conventional interpretation

of the statute does not in any way offend this directive.

Finally, Mallinckrodt spotlights a comment from the floor

debate on section 7002, in which the bill's sponsor characterized

14
To the extent that Congress, within this new regime, intended
to allow EPA to defend its own policymaking prerogatives, it
appears to have placed the onus on EPA, rather than the courts, to
stand as the sentry at the gates. See S. Rep. No. 98-284, supra,
at 56 (explaining that "if the Administrator believes a citizen
suit . . . is not being prosecuted in the public interest, he may
exercise the right to intervene . . . and seek from the court
restrictions or conditions upon the citizen suit").

-40-
the provision as giving citizens the power "to abate the most

serious kinds of hazardous waste situations: Those that may present

an imminent and substantial endangerment." 130 Cong. Rec. 2081,

2815 (1984) (statement of Sen. Mitchell). This one remark cannot

outweigh the substantial countervailing evidence that the citizen

suit provision was intended to empower private citizens by granting

them relatively broad authority to litigate when EPA had not acted

in the face of a reasonable prospect of serious, near-term harm.

See Weinberger v. Rossi, 456 U.S. 25, 35 (1982).

Legislative history is often a mixed bag. Parties

frequently are able to mine nuggets from it selectively, picking and

choosing isolated statements that serve particular (sometimes

conflicting) ends. Here, the legislative history is less than

pellucid. On the whole, however, it tends to support an expansive

reading of the "imminent and substantial endangerment" standard for

liability under RCRA § 7002(a)(1)(B).

To sum up, the combination of the word "may" with the

word "endanger," both of which are probabilistic, leads us to

conclude that a reasonable prospect of future harm is adequate to

engage the gears of RCRA § 7002(a)(1)(B) so long as the threat is

near-term and involves potentially serious harm. The language,

structure, purpose, and legislative history of the provision will

not comfortably accommodate the more restricted reading that

Mallinckrodt espouses. While there may be good and wise reasons to

-41-
adopt a regime in which EPA determinations of environmental

liability are exclusive, it is Congress's place, not ours, to

construct such a regime. To this date, Congress has not done so.

Given our conclusion that the conventional interpretation

of RCRA § 7002(a)(1)(B) is correct, the remainder of the liability

inquiry falls neatly into place. None of Mallinckrodt's arguments

persuade us that the district court either misconstrued this

standard or misapplied it to the facts of this case. While an

imminent and substantial endangerment requires a reasonable prospect

of a near-term threat of serious potential harm, the court below

made supportable findings that suffice to bring this case within the

compass of that standard. See, e.g., Me. People's Alliance, 211 F.

Supp. 2d at 245 (concluding that methylmercury is a "highly toxic

substance"); id. at 251 (concluding that, in an aquatic system,

"methylation is a continuous process that can go on for decades").

Based on these and other well-founded findings, the plaintiffs

established that the potential risk from mercury is serious and

likely to be present here and now. In turn, these findings support

a conclusion that, as the district court held, there may be an

imminent and substantial endangerment to the lower Penobscot River.

No more is exigible.

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IV. THE REMEDY

Our environmental odyssey is not yet finished.

Mallinckrodt contends that the district court committed an abuse of

discretion in ordering it to fund a study of the lower Penobscot.

This contention is rooted in the notion that a court must

balance the relevant harms before granting injunctive relief under

an environmental statute — even if the statute specifically

authorizes that type of relief. See United States v. Bethlehem

Steel Corp., 38 F.3d 862, 867 (7th Cir. 1994). Mallinckrodt would

have us achieve this balance by applying the familiar four-part

framework for determining the appropriateness of injunctive relief.

Under that framework, the injunction-seeker "must demonstrate: (1)

that it has suffered an irreparable injury; (2) that remedies

available at law, such as monetary damages, are inadequate to

compensate for that injury; (3) that, considering the balance of

hardships between the [parties], a remedy in equity is warranted;

and (4) that the public interest would not be disserved by a

permanent injunction." eBay Inc. v. MercExchange, L.L.C., 126 S.

Ct. 1837, 1839 (2006).

Conceptually, we agree with Mallinckrodt that a trial

court, in an environmental case, should consider the balance of

relevant harms before granting injunctive relief, even though the

statute itself authorizes such relief. The familiar four-part

framework for injunctive relief is a suitable guide in such

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situations. We caution, however, that the operation of that

framework is inevitably colored by the nature of the case and the

purposes of the underlying environmental statute (here, RCRA).

Against this backdrop, Mallinckrodt insists that the

district court mishandled the third of the four enumerated elements

by failing adequately to account for the onerous hardships that the

study would impose and contrast those hardships with the meager

benefits that the study might generate. In a nutshell,

Mallinckrodt's position is that the study will saddle it with a

staggering economic burden — a burden so open-ended that the overall

cost cannot be predicted with any assurance — yet will yield

supposed benefits to the plaintiffs' members that are at best

speculative and at worst ephemeral. In this regard, Mallinckrodt

stresses that it is an open question whether the lower Penobscot is

actually in need of any remediation.15

One difficulty with Mallinckrodt's position is that it

treats this injunction like a garden-variety injunction and, in the

bargain, undervalues the extent of the equitable discretion

possessed by a district court after a finding of liability under

15
Mallinckrodt suggests that because Dr. Livingston
acknowledged a dearth of information concerning the current
condition of the lower Penobscot, the district court did not have
sufficient facts before it to make an informed weighing. It also
suggests that the court neglected to accord due respect to EPA's
tentative view that the proposed media protection standards would
adequately ensure the river's safety. Whatever force these
suggestions may have — and we do not imply that they have any —
they go mainly to liability, not remedy.

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RCRA § 7002(a)(1)(B). While Mallinckrodt's hardships are relevant

to the acceptability of a RCRA remedy, the argument that hardship

must always be outweighed by deliverable benefits offends the logic

of Price. Even on Mallinckrodt's restrictive reading of that

decision, Price holds that "Congress sought to invoke the broad and

flexible equity powers of the federal courts in instances where

hazardous wastes threaten[] human health." 688 F.2d at 211.

Ironically, Mallinckrodt dresses this argument in the

raiment of a defense of judicial prerogatives. It cites Weinberger

v. Romero-Barcelo, 456 U.S. 305, 313 (1982), for the proposition

that judges should not lightly assume that Congress has stripped

courts of their equitable discretion. But that is a red herring:

while it is true that a district court is not commanded, regardless

of the circumstances, to issue an injunction after a finding of

liability, the court below was under no misapprehension on this

score. In reality, Mallinckrodt wishes to restrict, not preserve,

the equitable discretion of the district courts, and the case law

that it cites is therefore beside the point.

In reviewing a district courts exercise of its equitable

discretion under such circumstances, we think it fully appropriate

to acknowledge the statutory scheme under which liability was found.

Given the strong statement in Price, embraced by the Senate Report,

advocating the exercise of equitable remediation of environmental

hazards, we perceive a congressional thumb on the scale in favor of

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remediation. With this backdrop in place, we are unwilling to say

that the district court abused its discretion either by starting

with the proposition that its primary concern ought to be how best

to remedy a potentially serious near-term environmental hazard or

by granting relief notwithstanding the absence of a showing that the

remedy's demonstrable benefits exceeded its probable costs.

This is not to say that the costs associated with

injunctive relief are immaterial; we can imagine circumstances in

which the expense entailed in carrying out a particular remedial

plan might dwarf the potential benefits to the environment or to

human health. Here, however, the anodyne chosen by the district

court does not seem so vastly disproportionate to the threatened

harm as to warrant, from the vantage point of a cold appellate

record, a recalibration of the balance.

This conclusion is reinforced by the fact that

Mallinckrodt has not identified any less burdensome, more cost-

effective remedy that the court could have imposed to address the

perceived environmental harm.16 Where, as here, a polluter has

16
Mallinckrodt does mention, albeit in passing, that the
district court committed an abuse of discretion in not "requiring
an estimate of [the study's] overall costs." Appellant's Br. at
62. Although it certainly would be preferable for a court to
establish with some exactitude the extent of the financial burden
imposed by a particular remedy, that degree of precision is
sometimes infeasible or impractical. The court below was cognizant
of this shortcoming and took pains to note in the order approving
the study plan, entered on August 10, 2005, that "if necessary and
at the appropriate time, the Court will require the preparation by
the Study Panel of a budget formulation for any remedial plan or

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failed to articulate a "nice adjustment and reconciliation between

the public interest and private needs," Hecht Co. v. Bowles, 321

U.S. 321, 329 (1944), a burdensomeness argument rarely will gain

much traction.

Taking a slightly different tack, Mallinckrodt

characterizes the study-plan order as unfair. It should not be

forced to pay the entire cost of the study, it complains, because

it is not the only entity to have contributed to the pollution of

the lower Penobscot. That plaint rings hollow. While Mallinckrodt

was not the sole source of mercury contamination, it was a dominant

one, so in that sense its claim of inequitable treatment comprises

more cry than wool.

At any rate, RCRA liability, generally speaking, is joint

and several. See Cox, 256 F. 3d at 301 n.37. The joint and several

nature of environmental liability makes it fitting to hold a single

polluter responsible for the totality of the damage where, as here,

the harm is indivisible. See id.

We have said enough on this score. Once liability has

been found, equitable relief in RCRA citizen suits is largely in the

informed discretion of the trial court. For aught that appears, the

effort which may result from the first phase" of the study. Given
the complex nature of the situation and the existence of this
safety valve, we find the absence of more definitive cost
parameters tolerable.

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court below did not abuse this discretion in its choice of a condign

remedy.

V. CONCLUSION

We need go no further. Despite an impressive array of

arguments, skillfully presented by extraordinarily able counsel,

Mallinckrodt has not persuaded us that the plaintiffs lack standing

to sue, that its cramped interpretation of RCRA § 7002(a)(1)(B) is

what Congress had in mind, or that the district court acted outside

the realm of its discretion in fashioning a remedy for the

threatened harm. Consequently, we uphold the district court's

rulings in all respects.

Affirmed.

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