21

- 1354 Talarico Bros. B ldg. Corp., et al. v. Union Carbide Corp., et al. 

### I N THE 

# U NITED 

# S TATES 

# C OURT 

# O F 

# A PPEALS 

# F OR 

# T HE 

# S ECOND 

# C IRCUIT

____________________ August Term, 202 1 Argued: May 20 , 2022 Decided: July 1 3 , 202 3
No. 21

- 1354

____________________ T ALARICO B ROS
. B UILDING C ORP ., J OSEPH L OZINA , S R ., J OSEPH L OZINA , J R ., J OHN G RACE , P HILIP P ALMERI , M ARK S CHULER , T HERESA S CHULER , C ONSTANTINO A RGONA , C HRISTINE A RGONA , J OHN R AYMOND , H AROLD W ADE , W ALTER M ICHAELS , B ARBARA M ICHAELS , R OBERT W ARD , B ETTY M O T IC K A , T HE W HEELHOUSE , I NC ., T HOMAS H ARRISON , D EBORAH H ARRISON , G ARY E BERSOLE , D IETRICK B ROTHERS , I NC ., P AUL Z IUKO , D IANE Z IUKO , 8001 B UFFALO A VE ., I NC
. , 9524 N IAGARA F ALLS B OULEVARD , LLC, B OWLEN E NTERPRISES , L TD ., 9540 NFB, LLC, G REATER N IAGARA B UILDING C ENTER , I NC ., AND J OSEPH C. W EBER , I NC
. , Plaintiffs

- Appellants ,

v. U NION C ARBIDE C ORPORATION , O CCIDENTAL C HEMICAL C ORPORATION , AND B AYER C ROP S CIENCE I NC
. , Defendants

- Appellees

.

____________________ Before: J ACOBS , N ARDINI , and R OBINSON , Circuit Judges

.2 Twenty

- eight individuals and businesses commenced this citizen suit u nder the Resource Conservation and Recovery Ac t (“RCRA”) , which creates a private right of action against any entity that has “contributed . . . to the past or present handling, storage, treatment, transportation, or disposal of any solid or hazardous waste which may present an imminent and substantial endangerment to health or the environment.” 42 U.S.C. § 6972(a)(1)(B). The plaintiffs complain of elevated levels of radiation detected on their land and seek to hold responsible three entities that operated nearby chemical plants during the twentieth century

. The United States District Court for the Western District of New York (Skretny, J. ) dismissed the complaint for failure to state a claim , holding , among other things, that the radioactive materials found on the plaintiffs’ properties fall outside the scope of RCRA because they we re recycled industrial byproducts rather than discarded waste. The defendants raise a host of additional arguments in support of dismissal. For the reasons explained herein, we affirm in part , vacate in par t , and remand for proceedings consistent herewith.

____________________ J OHN G. H ORN ( Paul D. Sylvestri and Daniel J. Altieri, on the brief ), Harter Secre s t & Emery LLP, Buffalo, NY, for Plaintiffs

- Appellants

. M ATTHEW L. B USH ( John Ewal d , on the brief ) , King & Spalding LLP, New York, NY , for Defendant

- Appellee Union Carbide Corporation

. Kevin M. Hogan and Joshua S. Glasgow, Phillips Lytle LLP, Buffalo, NY, for Defendant

- Appellee Occidental Chemical Corporation

. James Wylie Donald , McCarter & English LLP, Washington, DC, for Defendant

- Appellee Bayer CropScience Inc

.3 D ENNIS J ACOBS , Circuit Judge : In this citizen suit under the Resource Conservation and Recovery Act (“RCRA”), twenty

- eight individuals and businesses complain of elevated levels
of radiation detected on the properties they own or occupy . It is alleged that three operators of ne arby chemical plants contaminated multiple sites throughout a swath of Western New York by disposing of toxic byproducts over decades, beginning eighty

- odd years ago.
T he United States District Court for the Western District of New York (Skretny, J. ) dismissed the first amended complaint , reasoning that the
radioactive material found on the p laintiffs’ properties was not “discarded” solid
waste subject to regulation by R CRA, but rather waste that was recycled for gravel and other construction uses . That conclusion was premature ; whether
the material was “discarded” depends on the circumstances , and the c omplaint
states just enough to warrant discovery

. In other respects, though, the c omplaint is truncated and unhelpful : we are left guessing who did what, when, where, and how. It is a fair question whether
these blanks can ever be filled in, given that the relevant facts reach back to the4 1940s

. Nevertheless, RCRA is a remedial environmental statute with
considerable give. For the reasons explained below, we conclude that , as to defendants Union Carbide Corporation and Occidental Chemical Corporation,
the complaint plausibly allege s the elements of a citizen suit under RCRA , or the plaintiffs have identified extrinsic evidence that may render amendment fruitful. However, as against defendant Bayer CropScience Inc., there are no particularized allegations from which liability can reasonably be inferred

. We
t herefore affirm in part ; and we vacate in part and remand to give the p laintiffs

a n opportunity to seek leave to amend their c omplaint

. BACKGROUND
Defendants (and, as relevant, their corporate predecessors) Union Carbide Corporation (“Union Carbide”), Occidental Chemical Corporation (“Occidental”), and Bayer Crop S cience Inc. (“Bayer”) ( together , the “Defendants”) operated chemical manufacturing plants during the twentieth century. The plaintiffs are twenty

- eight owners and/or occupants of residential
and commercial properties located near the D efendants’ facilities in Niagara and
Erie Counties (together, the “Plaintiffs”)

.5 According to the first amended complaint (the “ Complaint ”) , the Defendants’ industrial activity generated volumes of radioactive byproducts
from materials containing thorium, uranium, phosphorus , zirconium, and other
elements

. One such byproduct was sla g, a fragmented, rock

- like material that can be used as aggregate for construction purposes. S tarting in the 1940s and continuing through at least the 1970s , the D efendants allegedly disposed of their
radioactive waste on the P laintiffs’ properties, where elevated radiation levels
have since been detected. In support of these claims , the Complaint references government

sponsored radiological evaluations dating back half a century

. One publication , called the Oak Ridge Report , summarized t he results of a 1984 study of radiation hotspot s conducted in the Niagara Falls area . J .K. Williams & B.A. Berven, Oak Ridge National Laboratory, Results of Radiological Measurements Taken in the Niagara Falls, New York, Area (1986) ; see Am. Compl. ¶¶ 38

– 39. According to that study , surveyors identified phosphate slag at dozens of sites , Oak Ridge Report at xi, 6

– 7 ; Plaintiffs allege that several of their properties were among those impacted. T h e slag was used in asphalt driveways and parking lots , and was thought to have originated from the production of elemental phosphorus by6 Occidental’s corporate predecessor. Id. at xi, 5. The Oak Ridge Report also
determined that some soil and rock samples contained thorium

- bearing material , which may have originated from mineral extraction elsewhere in the region

. Id.
at 5. It is alleged that, more recently, investigations conducted on behalf of
certain Plaintiffs confirmed the continuing presence of elevated levels of
radiation at several of the properties that were evaluated

. The EPA also allegedly found elevated radiation levels at or near three locations

— Upper Mountain Road, Niagara Falls Boulevard , and Robert Street

— which encompass multiple of the Plaintiffs’ properties

. With respect to at least some of those sites , the EPA determined that the radioactive materials “may present an imminent and substantial endangerment to public health, welfare, or the environment.” Am. Compl. ¶ 44. The Complaint states upon information and belief that the remaining Plaintiffs’ pro perties are contaminated with material that matches or is very similar to material detected at locations the EPA found to be dangerous

. As of the filing of the Complaint, the EPA had removed radioactive waste
from two discrete areas at certain of the Plaintiffs’ properties located on the Niagara Falls Boulevard site

. When t hose projects ran out of money, the EPA7 demobilized , advising the Plaintiffs that it ha d no definite plan or timetable for resuming the work. A significant volume of waste allegedly remains at th ose site s and will cost millions to remedy

. The Plaintiffs commenced this action in 2017, assert ing a federal claim
under RCRA’s citizen suit provision and five claims under New York state law. They seek injunctive relief as authorized by RCRA, including an order that the Defendants fully evaluate each of the Plaintiffs’ properties and, where necessary,

remove any and all radioactive solid wastes found there

. The Defendants jointly moved to dismiss the Complaint on several grounds. In opposition, the
Plaintiffs attempted to supplement the record with more than a dozen
documents , which the district court evidently (and correctly) ignored when ruling on the motion. 1 T he court dismissed the RCRA claim under Rule 12(b)(6)
and declin ed to exercise supplemental jurisdiction over the state law claims

. This appeal followed.

1 W hen “presented with matters outside the pleadings,” a district court must either “ exclude [] the extrinsic documents” or “ convert the motion to one for summary judgment

. ” Chambers v. Time Warner, Inc. , 282 F.3d 147, 154 (2d Cir. 2002) (citations omitted)

. We assume the former route was taken here, given that there was no conversion to summary judgment and the court’s opinion does not mention the documents.8 DISCUSSION
We review de novo a district court’s dismissal of a c omplaint for failure to
state a claim

. See Mirkin v. XOOM Energy, LLC , 931 F.3d 173, 176 (2d Cir. 2019) . This appeal also implicates subject matter jurisdiction and timeliness.
As to those issues, we review the court’s legal conclusions de novo and factual findings for clear error. See Somoza v. N.Y.C. Dep’t of Educ

. , 538 F.3d 106, 112 (2d Cir. 2008) (statute of limitations) ; APWU v. Potter , 343 F.3d 619, 623

– 24 (2d
Cir. 2003) (jurisdiction)

. I On appeal, the Defendants renew the argument that the federal courts lack jurisdictio n over claims by certain of the Plaintiffs. The Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (“CERCLA”) , 42 U.S.C. § 9601 et seq. , was enacted a few years after RCRA to facilitate “the prompt and effective cleanup of hazardous waste sites.” Niagara Mohawk Power Corp. v. Chevron U.S.A., Inc. , 596 F.3d 112, 120 (2d Cir. 2010) (citing B.F.
Goodrich Co. v. Murtha , 958 F.2d 1192, 1197

– 98 (2d Cir. 1992) ). “[T]o prevent
time

- consuming litigation which might interfere with ” that goal, section 113(h) of
CERCLA withdraws “federal jurisdiction over challenges to ongoing CERCLA9 removal [or remedial] actions [by the EPA] , including those brought under
RCRA.” Potter , 343 F.3d at 624 (internal quotation marks and citation s omitted)

. Specifically, s ection 113(h) provides that “[n]o federal court shall have [federal question] jurisdiction . . . to review any challenges to removal or
remedial action selected under ” the Act. 42 U.S.C. § 9613(h) . This provision is

a “blunt withdrawal of federal jurisdiction

. ” Potter , 343 F.3d at 624 ( quoting McClellan Ecological Seepage Situation v. Perry , 47 F.3d 325, 328 (9th Cir. 1995) ). The term “remove” is broadly defined “ to include not only the cleanup and
removal of [waste] , but also the undertaking of studies, investigations, testing, and other information gathering activities . . . .” Id. ; see also 42 U.S.C. §§ 9601(23), 9604 (b)

. And a suit constitutes a “challenge” to EPA activity under section 113(h) if it so much as “ i nterferes with the implementation of a CERCLA remedy

. ” Broward Gardens Tenants Ass ’ n v. E.P.A. , 311 F.3d 1066, 1072 (11th Cir. 2002) (citing Costner v. URS Consultants, Inc. , 153 F.3d 667, 675 (8th Cir. 1998) ) ; see also Razore v. Tulalip Tribes of Wash

. , 66 F.3d 236, 239 (9th Cir. 1995) (holding court lacked jurisdiction over citizen suit that , if successful, would10 “dictate specific remedial actions and

. . . alter the [EPA’s] method and order for cleanup” (internal quotation marks omitted) ). Still, EPA activity does not bar access to the courts indefinitely: jurisdiction is restored upon the co nclusion of the removal or remedial work

. See El Paso
Nat

. Gas Co. v. United States , 750 F.3d 863, 882 (D.C. Cir. 2014) (“[N]othing in [CERCLA section 113(h)] . . . obviously bars a renewed RCRA claim after a removal or remedial action has concluded.”); Cannon v. Gates , 538 F.3d 1328, 1332 (10th Cir. 2008) (“Section 9613(h) . . . does not preclude actions to challenge a remedial plan after that plan has been compl eted. ” ) ; see also Boarhead Corp. v.
Erickson , 923 F.2d 1011, 1019 (3d Cir. 1991) (“[Section 113(h)] shows Congress concluded that disputes about who is responsible for a hazardous site [and] what measures actually are necessary to

. . . remove the hazard

. . . should be dealt with after the site has been cleaned up .”). In dispute here is whether the EPA i s in fact actively engaged in removal
or remedial work at any of the Plaintiffs’ properties. The Complaint states that the EPA initiated radiological evaluations at the Upper Mountain Road Driveway, Robert Street, and Niagara Falls Boulevard sites , and removed
radioactive solid wastes from certain areas along Niagara Falls Boulevard . Am.11 Compl. ¶ 65. It is further alleged that the EPA ceased investigation and clean

up efforts due to budgetary constraints and demobilized from the region , leaving
behind significant contaminat ion

. Id. While their motion to dismiss was pending, the Defendants obtained permission to sup plement the record to show that the EPA had resumed its work
at the Niagara Falls Boulevard site

. Since then, however, the EPA has published yet more recent updates indicating that the agency completed most if not all of
its work in the Niagara Falls and Lewiston, New York region by the spring of
2021. 2 So while t here seems to be no present bar to jurisdiction , at least with regard to some of th e properties the Plaintiffs identify, the district court on remand may undertake additional jurisdictional fact

- finding to explore this issue
further

. See Potter , 343 F.3d at 627 ( “Where jurisdictional facts are placed in

2 See E

. P

. A

. , “EPA Completes Cleanups at Three Niagara County Sites and Continues Investigation at Two Other Sites” (January 2023), available at https://www.epa.gov/ny/niagara

- county

- radiation

- removal

- sites; E. P

. A

. , “EPA Completes Cleanup Activities at the Niagara Falls Boulevard Site Niagara Falls, New York” (July 2020), avai lable at https://www.epa.gov/sites/default/files/2020

- 07/documents/niagara_falls_blvd_rad_fact_sheet_july_2020_final.pdf. We can take judicial notice of these government newsletters. See Cangemi v. United States , 13 F.4th 115, 124 n.4 (2d Cir. 2021) (tak ing judicial notice of the U.S. Army Corps of Engineers’ website).12 dispute, the court has the power and obligation to decide issues of fact by reference to evidence outside the pleadings

. ” (alteration omitted) (quoting
LeBlanc v. Cleveland , 198 F.3d 353, 356 (2d Cir. 1999) ))

. I I

“ RCRA is a comprehensive environmental statute that governs the treatment, storage, and disposal of solid and hazardous waste. ” Meghrig v. KFC W., Inc. , 516 U.S. 479, 483 (1996) (citing Chi

. v. Envtl. Def. Fund , 511 U.S. 328, 331

– 32 (1994))

. Although “[c] hief responsibility for the implementation and
enforcement of RCRA rests with ” the EPA, the Act “ permits private citizens to enforce its provisions in some circumstances .” Id. at 483

– 84 ; see also 42 U.S.C. § 6972 (citizen suit provision). As relevant here, the statute authorizes suit against any entity that has “ contributed

. . . to the past or present handling, storage , treatment, transportation, or disposal of any solid or hazardous waste
which may present an imminent and substantial endangerment to health or the environment.” 42 U.S.C. § 6972( a )( 1 )( B ) (emphasis added)

. The district court held that the P laintiffs failed to plausibly allege that the
radioactive material on their properties constitutes “ solid waste , ” reasoni ng that
the radiation attributable to recycled slag falls outside the scope of RCRA13 because the slag w as not “discarded.” See Talarico Bros. Bldg. Corp. v. Union Carbide Corp. , No. 17 Civ. 1041, 2021 WL 1610200, at *12

– 13 (W.D.N.Y. Apr. 26, 2021)

. The Plaintiffs contest this holding. Also contested is whether the
P laintiffs have e stablished that any suc h material “may present an imminent and substantial endangerment,” and that each individual D efendant “contributed ” to the presence of the waste on the P laintiffs’ properties.
A. “ Solid Waste”
RCRA defines solid waste as “any garbage, refuse, sludge . . . and other discarded material, including . . . material resulting from industrial, commercial, mining, and agricultural operations . . . .” 42 U.S.C

. § 6903(27)

. The statute

“ does not further define ‘ discarded material ,’ ” Conn

. Coastal Fishermen’s Ass’n v. Remington Arms Co. , 989 F.2d 1305, 1314 (2d Cir. 1993) , creating ambiguity as to whether the term encompasses recycled waste. T he few circuits to have
considered the issue seem to agree that byproducts “destined for future recycling by another industry may be considered ‘discarded’

. . . if they can reasonably be considered part of the waste disposal problem ” addressed by RCRA

. Safe Food
& Fertilizer v. E.P.A. , 350 F.3d 1263, 1268 (D.C. Cir. 2003), on r eh’g in part , 365 F.3d 46 (D.C. Cir. 2004) (citing Am. Petroleum Inst. v. E

. P

. A

. , 906 F.2d 729, 740

– 4114 (D.C. Cir. 1990) ); see also Owen Elec. Steel Co. of S.C. v. Browner , 37 F.3d 146, 150 (4th Cir. 1994) (endorsing the D.C. Circuit’s standard); United States v. ILCO,
Inc. , 996 F.2d 1126 , 1131

– 32 (11th Cir. 1993) (same). We agree.
Not all waste is problematic , though the issue is muddled . The House Report on RCRA observed that “ [m]uch industrial and agricultural waste is reclaimed or put to new use”

— for example, agricultural waste that is “returned
to the soil as fertilizer or soil conditioners.” H .R. Rep. No. 94

- 1491 (I) , at 2

– 3 (1976), reprinted in 1976 U.S.C.C.A.N. 6238, 6240. That sort of waste, the House Report explained, is “not considered to be discarded material within the meaning of [RCRA].” Id. Relying on that guidance, other circuits have concluded that industrial byproduct is not “discarded” waste if it is “destined for immediate reuse in another phase of the [same] industry’s ongoing production process.”
Am

. Mining Cong

. v. E

. P

. A

. , 824 F.2d 1 177 , 1185 (D.C. Cir. 1987) (“AMC I”) ; see also , e.g. , Safe Air for Everyone v. Meyer , 373 F.3d 1035, 1045 (9th Cir. 2004) (holding residue generated from the cultivation of bluegrass was not discarded
because , among other things, it was reused “ in a continuous process of growing and harvesting Kentucky bluegrass seeds, the generating industry ”).15 Still, some recycled waste can be “discarded material” within the meaning
of RCRA. See AMC I , 824 F.2d at 1179 (“ Congress indeed intended that materials being recycled or held for recycling can be [solid] wastes . . . .”) (internal quotation marks and citation omitted)

. “T he statute and the legislative history [of RCRA] suggest that Congress expected EPA to regulate as solid and hazardous wastes certain materials that are destined for recyclin g.” Revisions
to the Definition of Solid Waste , 73 F ed. R eg. 64 , 668

- 01 , 64,671 (Oct. 30, 2008) (citations omitted)

. Likewise, t he House Report on RCRA cautioned that the “impr oper management” of certain types of discarded waste “could pose significant threats to human life and the environment.” H.R. Rep. No. 94

- 1491 (I)
at 4 ; see also 42 U.S.C. § 6902(a)(6) (stating RCRA seeks to “minimiz[e] the generation of hazardous waste . . . by encouraging . . . properly conducted recycling and reuse” (emphasis added) )

. Accordingly , the EPA has promulgated regulations for hazardous solid waste distinguishing legitimate (non

- regulable) and sham (regulable) recycling

. See generally Revisions to the
Definition of Solid Waste , 73 F ed. R eg. 64 , 668

- 01

. In the present case the district court held that the “Defendants’ disposal of slag material recycled as asphalt base is not the discar d of solid waste under16 RCRA” because “[s]uch reuse is not part ‘of the waste disposal problem’ that
RCRA addresses.” Talarico Bros. , 2021 WL 1610200, at *12

– 13 (citation omit ted) (quoting Am. Petroleum Inst. , 906 F.2d at 741 )

. That conclusion was premature, even assuming all the radioactive waste at issue was recycled as construction
material. Whether industrial byproducts that are eventually recycled nevertheless
constitute discarded solid waste depends on the circumstances

. Other circuits have weighed such considerations as the manner in which the material was stored prior to recycling, see A ss’n of Battery Recyclers, Inc. v. E.P.A. , 208 F.3d 1047, 1051 (D.C. Cir. 2000) ; how long the material sat before being put to beneficial use , see Owen , 37 F.3d at 148

– 49; whether the material was subject to a reclamation process , see ILCO , 996 F.2d at 1131; and how market participants
value the material , see Safe Food , 350 F.3d at 1269.
Given that some of the alleged disposal occurred generations ago, the Plaintiffs will need discovery to explore these and other p ertinent facts

. S uch
information may no longer be obtainable ; books and records dating to the mid

twentieth century may be as hard to come by as witnesses

. But that is not a problem for resolution at the pleading stage

. The Complaint states that: the17 D efendants engaged in industrial activity that generated radioactive byproducts, including slag; the D efendants transported and disposed of their radioactive byproducts on the P laintiffs’ properties; and studies have detected radioactivity at those properti es that is attributable, at least in part, to contaminated slag. Those allegations make it plausible that the materials at issue are “ discarded ” under RCRA and thus may constitute regulable “solid waste”

— subject to any other definitional issues not presented here

. B. “Imminent and Substantial Endangerment”
RCRA “ permits a private party to bring suit only upon a showing that the
solid or hazardous waste at issue ‘ may present an imminent and substantial endangerment to healt h or the environment. ’ ” Meghrig , 516 U.S. at 485 (quoting 42 U.S.C. § 6972(a)(1)(B)). That “standard is a broad one,” providing courts the ability “to grant affirmative equitable relief to the extent necessary to
eliminate any risk posed by toxic wastes.” Simsbury

- Avon Pres. Club, Inc. v. Metacon Gun Club, Inc. , 575 F.3d 199, 2 10 (2d Cir. 2009) (quoting 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) ). Still, a p laintiff must clearly allege facts demonstrating
each statutory element . “Threadbare recitals of the elements of [the] cause of18 action, supported by mere conclusory statements, do not suffice.” Ashcroft v. Iqbal , 556 U.S. 662, 6 7 8 (2009) (citing Bell Atl. Corp. v. Twombly , 550 U.S. 544, 555 (2007))

. At issue here are both the “imminent” and “substantial” requirements. An endange rment is “imminent” if there is “ a threat which is present now , although the impact of the threat may not be felt until later.” Meghrig , 516 U.S. at 486 (quoting Price v. U.S. Navy , 39 F.3d 1011, 1019 (9th Cir. 1994)). “ A finding of ‘ imminency ’ does not require a showing that actual harm will occur immediately so long as the risk of threatened harm is present .” Dague , 935 F.2d
at 1356 (2d Cir. 1991) ( citing Envtl. Def

. Fund v. E.P.A. , 465 F.2d 528, 535 (D.C.
Cir. 1972) ). So , a claim of “imminent” endangerment will fail if the waste “no longer presents

. . . a danger” that threatens to occur immediately. Meghrig , 516 U.S. at 485

– 86. On the face of it, the Plaintiffs’ claim of imminent endangerment is not compelling

. T he radioactive material was allegedly deposited on the P laintiffs’ properties as early as the 1940s; yet , as the Defendants point out, t he Complaint
do es not “identify a ny actual harm to health or the environment that has already
occurred.” Appellees’ Br. at 33.19 But RCRA “ does not require proof of actual harm

. ” Dague , 935 F.2d at
1356. The statute’s “ combination of the word ‘may’ with the word ‘endanger,’
both of which are probabilistic ,” indicates that “ a reasonable prospect of future harm is adequate to engage the gears of § 6972(a)(1)(B) so long as the threat is

near - term . . . .” Simsbury

- Avon , 575 F.3d at 211 (alteration omitted) (quoting Me. People’s All. v. Mallinckrodt, Inc. , 471 F.3d 277, 2 96 (1st Cir. 2006 ) )

. “ A n

‘ imminent hazard ’ may be declared at any point in a chain of events which may ultimately result in harm to the public

. ” Dague , 935 F. 2 d at 1356 (internal quotation marks omitted) (quoting Envtl. Def. Fund , 465 F.2d at 535 )

. L atent festering may be a legitimate link in th e chain. This helps explain why “ RCRA contains no statute of limitations

. ” 3 Meghrig , 516 U.S. at 486. Left unremedied, a threat of harm due to

3 In the absence of a statutory limitations period, the Defendants urge us to apply 28 U.S.C. § 2462 , which imposes a five

- year limitations term for any suit “for the enforcement of any civ il fine, penalty, or forfeiture” not otherwise subject to a statute of limitations . That provision is inapplicable when, as here, the plaintiffs seek only equitable relief. Although the Complaint sought damages, the district court credited the Plaintiffs’ subsequent withdr awal of that request in their opposition to the motion to dismiss. In any event, pecuniary relief is not available under RCRA’s citizen suit provision. See 42 U.S.C. § 6972(a)(1)(B); see also Meghrig , 516 U.S. at 488 (holding citizens cannot recover costs for past cleanup efforts under RCRA ).20 environmental contamination might persist for decades

. And private litigants may sensibly await the often prolonged efforts of government at various levels.
The district court thus erred in treating the “imminent” requirement as a
deadline for prompt legal action. See Talarico Bros. , 2021 WL 1610200, at *14 (holding plaintiffs failed “to state a RCRA claim for imminent harm” because they allege “ decades

- old harm only legally addressed in 2017 ” ). The pertinent question is not whether the plaintiff has “diligently pursue [ d ] [its] clai ms,” id. , but whether the plaintiff has made a “showing that a risk of threatened harm [remains] present” at the time of filing the complaint, Simsbury

- Avon , 575 F.3d at 210 (internal quotation marks and citation omitted). The Complaint survives this indulgent test , given the following allegations

. T he Plaintiffs’ properties are contaminated with radioactive materials containing uranium, thorium, and other potentially dangerous
elements

. Per the Oak Ridge Report , as of 1986 , at least 100 instances of elevated gamma radiation were detected in the Niagara Falls region, and several of the
Plaintiffs’ properties were impacted

. M ore recent EPA evaluations found that elevated levels of radiation persist around the Niagara Falls Boulevard and Robert Street properties , and the agency determined that the radioactive solid21 waste at those sites may present an imminent and substantial endangerment

. See Am. Compl. ¶¶ 42, 44. T he EPA initiated clean

- up activity at discrete
locations at the Niagara Falls Boulevard site , but terminated th e projects due to budgetary constraints, leaving a lot of contamination unremedied

. Id. ¶ 65. A s
t o the other Plaintiffs’ properties, the radioactive solid waste is the same as or very similar to that which gave rise to the EPA’s findings of endangerment

. Id. ¶ 45. As a result, the Plaintiffs and their visitors are being exposed to levels of
radiation that increase their health risk s . These allegations go beyond a purely “speculative prospect of future harm.” See Simsbury

- Avon , 575 F.3d at 214. Much more will be required to support a claim that waste buried half a century ago ( or more ) pose s a n imminent threat of harm today

. Nevertheless ,

“ a well

- pleaded complaint may proceed even if it strikes a savvy judge that actual proof of those facts is improbable .” Twombly , 550 U.S. at 556

. A cceptin g the Plaintiffs’ factual allegations as true, we conclude that t he Complaint plausibly allege s a risk of imminent endangerment under RCRA

. A “substantial” endangerment entails a “serious” threat of injury

. Simsbury

- Avon , 575 F.3d at 210. This bar is not particularly high. T here must
be “ reasonable cause for concern that someone or something may be exposed to22 risk of harm . . . in the event remedial action is not taken. ” Burlington N

. and Santa Fe Ry. Co. v. Grant , 505 F.3d 1013, 1021 (10th Cir. 2007) (citation omitted) ;

see also Simsbury

- Avon , 575 F.3d at 211

. Since p roof of actual injury is unnecessary to show endangerment under
RCRA , t he Complaint need not have included “specifics for the impact of the[]
elevated levels [ of radiation ] , such as medical injury claims, [or] depreciation in property values once radioactive materials were disclosed , ” as the district court seemed to require. Talar i co Bros. , 2021 WL 1610200, at *13

. The D efendants lik e wise demand too much , faulting the Complaint for lacking “ factual allegations sufficient to assess ‘ the severity of any harm that might occur.’” Appellees’ Br. at 30 (quoting Simsbury

- Avon , 575 F.3d at 211). Simsbury

- Avon , the case on which the D efendants rely, was decided at summary judgment. In that posture, we affirmed dismissal on the ground that the record was “insufficient to permit a factfinder to assess the magnitude of the possible
risk.” 575 F.3d at 211. The D efendants offer no authority requiring that level of
sp ecificity at the pleading stage

. Still, the Plaintiffs must plausibl y alleg e that the radioactivity is dangerous; “the mere presence” of radioactive materials does not suffice

. S ee Me. People’s23 All. , 471 F.3d at 282 (internal quotation marks and citation omitted)

. Th e Complaint repeatedly references “elevated” radiation levels , but elevated as compared to what? The 1986 Oak Ridge Report

— the only study named in the Complain t

— compares the detected gamma exposure rates to t hen

- t ypical background levels

. Th is is plainly insufficient to demonstrate that a serious risk of harm persists today.
This pleading deficiency might , however, be remediable. Attached to their opposition to the motion to dismiss, the P laintiffs submitted an EPA action
memorandum from 2016 for the Niagara Falls Boulevard site (the “ EPA Memorandum”). See Mem

. in Opp

. to Joint Mot

. to Dismiss , No . 17 Civ. 1041 ( W .D.N.Y.) (filed Feb. 15, 2018 ) (the “Plaintiffs’ Opp.”), Ex. 7

. The EPA
Memorandum reports that , a t a site encompassing the Niagara Falls Boulevard properties , the EPA detected Radium

- 226 in concentrations around eighty times the acceptable cancer risk value and concluded that “these radionuclides pose an immediate risk to public health, welfare, and the environment.” Id. at 12. It
cautions that radium has a long half

- life and that radium

- contaminated soils migra te through airborne dust, surface runoff , construction activities, and foot
traffic into on - site buildings , homes, and nearby residential areas. Id. at 11.24 Also included with the Plaintiffs’ opposition papers was a news article addressing the EPA’s cleanup efforts in the Niagara Falls area, which reported radioactivity detected at levels more than seventy

- five times higher than normal
at a site across the road from two of the Robert Street properties. Plaintiffs’ Opp., Ex. 9 at 2

– 3

. If o n remand the P laintiffs seek leave to amend to expressly incorporate
th ese (and potentially other) supporting documents , their claim of substantial endangerment may be advanced “across the line from conceivable to plausible

. ” Twombly , 550 U.S. at 570.
C. “Contributed To ” Finally, t o plead endangerment under RCRA, a complaint must plausibly allege that the defendant “contributed . . . to the past or present handling, storage, treatment, transportation, or disposa l” of the subject waste. 42 U.S.C. §
6972 (a)(1)(B)

. In the absence of a statutory definition of “contributed,” we give “the term its well

- established meaning.” Green Tree Fin. Corp.

- Alabama v. Randolph , 531 U.S. 79, 86 (2000) (citation omitted)

. As other circuits have
observed , “contribute” “ commonly means

. . . to ‘ have a share in any act or
effect. ’” Hinds Invs., L.P. v. Angioli , 654 F.3d 846, 850 (9th Cir. 2011) (quoting25 Webster’s Third New International Dictionary 496 (1993) ); see also Cox v. City of
Dall

. , 256 F.3d 281, 294 (5th Cir. 2001) (same ); United States v. Aceto Agric. Chems. Corp. , 872 F.2d 1373, 1384 (8th Cir. 1989) (same). This capacious definition accords with RCRA’s “cradle to grave” regulation of solid waste

. Chem. Waste Mgmt., Inc. v. Hunt , 504 U.S. 334, 33 7 n.1 (1992)

. W e conclude that the Complaint sets forth just enough individualized facts to plausibly demonstrate contribution by Union Carbide and Occidental, but not by Bayer

. As to Union Carbide, t he Complaint alleges that : it generated radioactive
solid wastes as byproducts of the production of compounds containing uranium and thorium at a Niagara Falls plant, Am. Compl. ¶ 50; elevated levels of radiation at the Plaintiffs’ properties are attributable to radioactive isotopes in the Radium 226 and Thorium 232 decay chains, which are present in the radioactive solid wastes found on these properties , id. ¶ ¶ 3 6

– 3 7; and agency documentation indicate s that radioactive solid wastes from Union Carbide ’s Niagara F alls plant are present at or near the Plaintiffs’ properties on Niagara Falls Boulevard , Robert Street, and Upper Mountain Road, id. ¶ 51. In addition,
one of the EPA reports attached to the P laintiffs’ opposition papers suggests that26 contaminated slag from the Union Carbide facility may have been used as fill at the Niagara Falls Boulevard properties. See Plaintiffs’ Opp., Ex. 6 at 1

. The allegations against Occidental are similar. According to the Complaint, Occidental generated radioactive slag when producing elemental phosphorous at its Niagara Falls plant

. Am. Compl. ¶ 52

. At least one government

- sponsored study concluded that Oc cidental’s phosphate slag makes
up the radioactive solid waste present at sites in the Niagara Falls area, including
at several of the P laintiffs’ properties

. I d

. ¶ 53. And t he Plaintiffs’ opposition papers included a 1978 letter from Occidental to the Niagara County Health Department , confirm ing that the company’s phosphorous operations generated slag byproduct that was dispersed throughout Western New York: some was sold to local construction contractors, some was transported to a landfill , and
some remained near Occidental’s old facilities. See Plaintiffs’ Opp., Ex. 2 at 1

. Union Carbide and Occidental are thus plausibly linked to specific activities that created the specific types of radioactive materials detected on specific Plaintiffs’ properties. It is therefore reasonable to infer that those
Defendants “contributed to” the handling of the solid waste giving rise to the
Plaintiffs’ RCRA claim. At least at this stage of the case, it is not fatal that the27 Complaint lacks particularized allegations regarding when and how the
radioactive waste was disposed ; those are gaps that might be filled in with discovery

. T he allegations against Bayer , however , are critically weaker

. The Complaint attributes the radiation detected on the Plaintiffs’ properties to radioactive isotopes in one or more of the Radium 226, Uranium 238 , and Thorium 232 decay chains

. See Am. Compl. ¶ 37. Y et neither Bayer nor its predecessor, Stauffer Chemical Company , is alleged to have used materials containing radium, uranium, or thorium , or capable of producing them

. I d. ¶ 54

. The Plaintiffs filed a supplemental report from 1982 regarding uranium and thorium generated from the production of phosphorous at Stauffer’s facility in Las Vegas, s ee Plaintiffs’ Opp., Ex. 14 ; but there is no allegation that the company engaged in similar activity in New York , see Am. Compl. ¶ 54. There is one probative allegation implicating Bayer: Stauffer’s Lewiston plant was located within 2,000 feet of the Robert Street p roperties and within a
mile of four of the Plaintiffs’ other properties

. See Am. Compl. ¶ 55

. But
p roximity alone

— without any identity of chemical composition or other28 allegation linking Bayer’s Western New York activity to the contamination of the Plaintiffs’ properties

— is insufficient to make Bayer’s contribution plausible.
CONCLUSION
For these reasons we AFFIRM IN PART that portion of the judgment dismissing the Complaint aga inst Bayer, VACATE IN PART the remainder of the judgment, and REMAND to permit the Plaintiffs an opportunity to seek
leave to amend

.