Pavement Coatings Technology v. United States Geological Survey

United States Court of Appeals

FOR THE DISTRICT OF COLUMBIA CIRCUIT

Argued December 14, 2020 Decided May 7, 2021

No. 20-5035

PAVEMENT COATINGS TECHNOLOGY COUNCIL,

APPELLANT

v.

UNITED STATES GEOLOGICAL SURVEY,

APPELLEE

Appeal from the United States District Court

for the District of Columbia

(No. 1:14-cv-01200)

Lawrence S. Ebner argued the cause for appellant. With

him on the briefs was David A. Kanter.

Joshua M. Koppel, Attorney, U.S. Department of Justice,

argued the cause for appellee. With him on the brief were

Ethan P. Davis, Acting Assistant Attorney General, at the time

the brief was filed, and Mark B. Stern, Attorney. Paul Cirino,

Trial Attorney, and R. Craig Lawrence, Assistant U.S.

Attorney, entered appearances.

Before: ROGERS, MILLETT and WILKINS, Circuit Judges.

Opinion for the Court filed by Circuit Judge WILKINS.

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WILKINS, Circuit Judge: The U.S. Geological Survey

(“USGS” or “Survey”) is the nation’s largest water, earth, and

biological science agency. Housed within the Department of

the Interior, it has no regulatory mandate and is instead relied

upon to provide unbiased and policy-neutral information to

decision-makers at the local, state, and federal level. The

Survey and its scientists regularly publish this research in

agency reports and scientific journals. Two studies, and the

records that underlie them, are at issue in this Freedom of

Information Act (“FOIA”) appeal.

With a note on the special role of summary judgment in

FOIA cases, we reverse and remand to the District Court with

respect to the model runs withheld under Exemption Five for

further proceedings consistent with this opinion. We affirm the

District Court’s ruling as to Exemption Six.

I.

A.

Requestor Pavement Coatings Technology Council

(“PCTC”) is a trade association for producers of refined coal

tar-based sealant. Coal tar sealant prolongs asphalt’s service

life by protecting it from degradation caused by sunlight, water,

and leaked oil or gasoline. It has also been identified as a major

source of polycyclic aromatic hydrocarbons (“PAHs”). A. 18.

There are different types of PAHs, sixteen of which are

considered priority pollutants by the Environmental Protection

Agency (“EPA”). See 40 C.F.R. Part 423, App. A; see also A.

18–19. PAHs are toxic, mutagenic, teratogenic, and some are

probable human carcinogens. A. 19. In the late 1990s,

scientists at Respondent USGS noted an upward trend in PAH

levels in sediment recovered from urban lakes.

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USGS Research Hydrologists Barbara J. Mahler and Peter

Van Metre undertook several studies to identify the sources of

PAHs in urban environments. Two of those studies—

“Contribution of PAHs from coal tar pavement sealcoat and

other sources to 40 U.S. lakes” (“urban lakes study”) and

“Coal-tar-based pavement sealcoat: An unrecognized source

of PAH to settled house dust” (“house dust study”)—and their

records are at issue here. Both studies identified coal tar sealant

as a major source of urban PAHs. USGS has released all of the

raw data underlying both studies.

Mahler and Van Metre produced computer modeling input

and output data to analyze this raw data. As described by Van

Metre, “[m]odeling is a broad term that generally means to

develop a mathematical model of some natural process” by

relating one or more variables (e.g., urban land use) to the

occurrence of other variables (e.g., the concentration of a

pollutant in local streams) in order to better understand how the

environment works. A. 23. Complicated models require

calibration, achieved by adjusting or replacing variables and

parameters that control the model in order to test how well the

model represents the natural process studied. In the urban lakes

study, Mahler and Van Metre sought to determine what PAH

sources—vehicle emissions, power plant emissions, or coal tar

sealant, among other sources—contributed to the PAHs they

measured in lake sediment samples collected across the United

States.

To do so, Mahler and Van Metre tested three widely used

source receptor models developed by the EPA. A source

receptor model attempts to isolate the source of contaminants

identified in a sample. Testing the three models with different

combinations of sediment samples and PAHs revealed that the

EPA’s “contaminant mass balance” (“CMB”) model was the

preferred choice. The CMB model, like the raw data it

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crunched, is publicly available. See United States

Environmental Protection Agency, Chemical Mass Balance

(CMB) Model, https://www.epa.gov/scram/chemical-mass-

balance-cmb-model (last visited Apr. 23, 2021). Mahler and

Van Metre did not publish the “exploratory decision-making

process” behind their choice to use the CMB model because

such a comparative modeling analysis “would be a major

undertaking” distinct from their goal of “using a given model

to evaluate sources in the environment.” A. 24.

Calibrating the CMB model required Mahler and Van

Metre to make several choices: they selected which lakes to

include and, from each lake, which samples. They decided

how to process that data before entering it into the model (for

example, by using the logarithm of the actual sample values or

tweaking how sample uncertainty was estimated). They chose

which types of PAHs to source. And they chose which sources

to include, since there are statistical limits on how many

sources the model can consider in a run. For example, it made

sense to the researchers to include coke-oven emissions for

lakes near Chicago, where coke ovens are still in operation, but

not for lakes in Washington State or Florida, where coke-ovens

are not.

The USGS scientists also ran combinations of variables

that the researchers believed were highly unlikely to occur in

the real world to see how the model would respond to

adjustments to those variables. Other runs allowed them to

“investigate alternative hypotheses for the causes of . . . PAH

contamination.” A. 24. The scientists also shifted parameters

for various runs, including instructing the model to run a

certain number of iterations before arriving at a solution.

Given these possible combinations of inputs, “the possible

outcomes of a particular model—even if used on the same data

set—are virtually limitless.” A. 26. Van Metre explained that

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the process of selecting “samples, source profiles, PAHs and

modeling parameters reflects the working thoughts of a

scientist as he or she attempts to make sense of the data

presented.” A. 26. Mahler described the process as “not

dissimilar to a writer trying out different combinations of

words or paragraphs in a draft document in an effort to create

the most logical sequence.” A. 14.

From the more than 200 model runs tested, Van Metre and

Mahler chose four representative runs “on the basis of good

quantitative and qualitative model performance.” A. 27. These

four runs were “in general agreement with the vast majority of

the 200 models tested,” though there was “considerable

variability in those results that could be exploited to make it

appear” that USGS overstated coal tar sealant’s role as a

source. A. 27. The record does not disclose whether peer

reviewers—either within USGS or engaged by the publishing

journals—reviewed the 196 model runs that were not selected

for publication. At oral argument, counsel for USGS suggested

that approving officials within the agency “may have seen

some [of the 196 model runs] in the preliminary drafts,” but

conceded that neither scientist declared that they selected the

four chosen model runs to inform the ultimate decision-

maker’s decision whether to publish the urban lakes study.

Oral Arg. Tr. 16:22–17:9; 27:19–28:12; see also 21:13–17.

Requestor PCTC engages experts who use the Survey’s

data to conduct in-depth post-publication peer reviews “to

better understand data that has been collected about products

made by PCTC members.” To test the soundness of the urban

lakes study’s methods and conclusions, PCTC seeks the

computer modeling input and output data Mahler and Van

Metre produced while analyzing their raw data. PCTC takes

issue with USGS’s decision not to publish the exploratory

decision-making process, namely, the inputs and parameters

6

for each run. PCTC believes that Mahler and Van Metre

manipulated the model inputs to ensure that outputs identified

coal tar sealants as the source. Mahler and Van Metre allegedly

achieved this result by using unweathered PAH source profiles

for the non-coal tar sealant sources and weathered samples for

the coal tar sealant source. According to PCTC, since “all

combustion sources of PAHs have similar PAH profiles and all

weather to similar, undistinguishable weathered profiles,

Mahler and Van Metre have rigged the model to guarantee that

most PAHs in the environment (which are all weathered) look

like what they have called [coal tar sealant].” A. 120. PCTC

points to this alleged manipulation to illustrate why it “must be

provided with the model runs it has requested to both attempt

to replicate the reasoning behind the work of Mahler and Van

Metre, and to defend itself against attempts to ban or restrict

the sale and use of [coal tar sealant].” A. 120. Van Metre’s

affidavit stated that providing PCTC with the model runs

would “give [it] yet another tool to try and confuse the public

and discredit our work.” A. 27.

PCTC’s Executive Director, Anne LeHuray, testified in

her affidavit that concealing scientific processes is unsound

scientific methodology. She claimed that a “full account of the

work performed” is necessary to attempt to reproduce Mahler

and Van Metre’s research and pointed to the scientific journal

Nature’s conditions of publication, which require authors to

“make materials, data, code, and associated protocols promptly

available to readers without undue qualifications,” to support

the argument that these model runs would usually be revealed

to the scientific community and the public. A. 129, 168.

PCTC also seeks location information for dust samples

collected as part of the urban house dust study. USGS

scientists collected samples from twenty-three Austin, Texas

residences in mid-2008. USGS labeled each sample with a

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sample ID and created sample sheets linking the sample IDs

and concentrations of PAHs found in each associated sample.

Participants filled out a questionnaire and answered follow-up

questions to identify factors that may have affected PAH

concentrations in their house dust. The questions asked

participants to disclose how many adults and children lived in

the residence, whether they smoked, how often they left their

homes and how long they were gone, their eating and cooking

habits, and whether and how long their windows were kept

open. Volunteers were told their samples would be used only

for the purposes of the study and that personally identifiable

information would remain confidential.

USGS produced all sample sheets and questionnaires (with

the volunteer’s name and address, and sample and site IDs,

redacted) and a “means by which to match the responses to the

results of the sample analysis.” A. 55, 148. However, PCTC

seeks the location information associated with each sample in

order to “conduct a study (or a post-publication peer review of

the USGS’ [sic] dust study) which examines the potential role

alternative (non-[coal tar sealant]) factors—known as

confounders—may have contributed to the PAH levels found

in the USGS dust study.” A. 171. PCTC argues that it must be

provided with volunteers’ addresses because “[w]ithout the

addresses of locations used in the USGS dust study, PCTC will

not be able to construct a study design that adequately

replicates the USGS dust study.” A. 172.

B.

In 2011, PCTC filed a FOIA request seeking release of

USGS records relating to the agency’s coal tar sealant studies.

PCTC sought eight years of documents, including

correspondence regarding coal tar sealant and all documents

relating to studies or publications about coal tar sealant, as well

8

as all lab data for coal tar sealant-related research. USGS

produced 52,000 pages of records, including all raw data

collected for both the urban lakes and house dust studies, but

withheld the modeling data and personally identifiable

information relevant to this appeal. USGS withheld the model

runs under FOIA’s Exemption Five on the ground that

“[r]elease of the exploratory analysis would inhibit the ability

to freely explore and analyze data without concern for external

criticism.” A. 50. It withheld the house dust study participants’

personal information under FOIA’s Exemption Six because

“[r]elease would constitute a clearly unwarranted invasion of

personal privacy” and “would not serve a public interest

because the pertinent scientific data associated in this category

of records is already released.” A. 55–56.

After PCTC filed its complaint in 2014, the parties

submitted cross-motions for summary judgment. The District

Court ruled on those motions on November 13, 2019, issuing

an order granting USGS’s motion for summary judgment and

denying PCTC’s cross-motion. PCTC timely appealed. The

District Court exercised jurisdiction under 5 U.S.C.

§ 552(a)(4)(B) and 28 U.S.C. § 1331. We have jurisdiction

under 28 U.S.C. § 1291.

II.

As we have often observed, “FOIA protects the basic right

of the public to be informed about what their government is up

to.” Hall & Assocs. v. EPA, 956 F.3d 621, 624 (D.C. Cir. 2020)

(quoting Competitive Enter. Inst. v. Office of Sci. & Tech.

Policy, 827 F.3d 145, 150 (D.C. Cir. 2016) (internal quotations

omitted)). FOIA, 5 U.S.C. § 552, requires agencies to disclose

records upon request, unless they fall within one of nine

exemptions. U.S. Fish & Wildlife Serv. v. Sierra Club, Inc.,

— U.S. —, 141 S. Ct. 777, 785 (2021). We construe these

9

exemptions narrowly. Milner v. Dep’t of Navy, 562 U.S. 562,

565 (2011).

We review the District Court’s decision on summary

judgment in a FOIA case de novo. Hall & Assocs., 956 F.3d at

629. Summary judgment is appropriate only “if the movant

shows that there is no genuine dispute as to any material fact

and the movant is entitled to judgment as a matter of law.” Id.

(quoting FED. R. CIV. P. 56(a)); see also Petroleum Info. Corp.

v. U.S. Dep’t of Interior, 976 F.2d 1429, 1433 (D.C. Cir. 1992)

(“This circuit applies in FOIA cases the same standard of

appellate review applicable generally to summary judgments.”

(citing Wash. Post Co. v. Dep’t of Health and Hum. Servs., 865

F.2d 320, 325–26 & n.8 (D.C. Cir. 1989))). “In the FOIA

context this requires that we ascertain whether the agency has

sustained its burden of demonstrating that the documents

requested are . . . exempt from disclosure.” Am. C.L. Union v.

U.S. Dep’t of Justice, 655 F.3d 1, 5 (D.C. Cir. 2011) (quoting

Gallant v. NLRB, 26 F.3d 168, 171 (D.C. Cir. 1994) and citing

5 U.S.C. § 552(a)(4)(B) (stating that “the burden is on the

agency to sustain its action”)). At this stage, “the inferences to

be drawn from the underlying facts . . . must be viewed in the

light most favorable to the party opposing the motion,” in this

case, requestor PCTC. Judicial Watch, Inc. v. U.S. Secret

Serv., 726 F.3d 208, 215 (D.C. Cir. 2013) (quoting Matsushita

Elec. Indus. Co. v. Zenith Radio Corp., 475 U.S. 574, 587

(1986) (internal quotations omitted)).

USGS seeks to withhold some 196 unpublished model

runs under Exemption Five. Exemption Five excludes from

FOIA’s disclosure requirements “inter-agency or intra-agency

memorandums or letters that would not be available . . . in

litigation with the agency.” 5 U.S.C. § 552(b)(5). “A form of

executive privilege, the deliberative process privilege covers

deliberative, pre-decisional communications within the

10

Executive Branch,” Nat’l Sec. Archive v. CIA, 752 F.3d 460,

462 (D.C. Cir. 2014), and was “intended to protect not simply

deliberative material, but also the deliberative process of

agencies,” Montrose Chem. Corp. of Cal. v. Train, 491 F.2d

63, 71 (D.C. Cir. 1974). To qualify for withholding,

information must be both pre-decisional and deliberative.

Petroleum Info. Corp., 976 F.2d at 1434.

With respect to the urban lakes study, USGS stumbles at

both hurdles. The agency first failed to introduce any evidence

establishing what role the requested model runs played in its

decision to publish the urban lakes study. Second, we find no

evidence on this record that disclosing the model runs would

expose the Survey’s decision-making process “in such a way

as to discourage candid discussion within the agency and

thereby undermine the agency’s ability to perform its

functions.” See Dudman Commc’ns Corp. v. Dep’t of Air

Force, 815 F.2d 1565, 1568 (D.C. Cir. 1987).

A.

USGS failed to carry its burden to show that the model

runs are pre-decisional. In order to establish that government

documents are pre-decisional, “the agency has the burden of

establishing what deliberative process is involved, and the role

played by the documents in issue in the course of that process.”

Coastal States Gas Corp. v. Dep’t of Energy, 617 F.2d 854, 868

(D.C. Cir. 1980); see also Paisley v. CIA, 712 F.2d 686, 698

(D.C. Cir. 1983), vacated in part on other grounds, 724 F.2d

201 (D.C. Cir. 1984). Put simply, a pre-decisional record is

one “prepared in order to assist an agency decisionmaker in

arriving at his decision.” Petroleum Info. Corp., 976 F.2d at

1434 (quoting Renegotiation Bd. v. Grumman Aircraft, 421

U.S. 168, 184 (1975)). The government says that the relevant

agency decision to which the model runs are assertedly pre-

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decisional is the Survey’s decision to adopt and publish the

urban lakes study in its own name. USGS Br. 15–16. PCTC

accepts that as the relevant decision for purposes of Exemption

Five. See PCTC Br. 22. But we are faced with a record devoid

of evidence that any decision-maker at USGS considered the

discarded model runs in determining whether and in what form

to publish the urban lakes study. The agency bears the burden

of explaining its decision-making process, but we have no

declaration that does so. Indeed, counsel for the agency

conceded as much at oral argument. See Oral Arg. Tr. 21:12–

22:1 (“I don’t believe that what the approving officials look at

is in the record.”). Counsel is correct.

All we are told is that “approving officials may have seen

some” of the discarded runs in preliminary drafts, id. at 17:1–2

(emphasis added), but this claim was made only at oral

argument and is unsupported by the record evidence. USGS

chose to identify its decision as the decision to publish, but it

did not explain how that decision was made, aside from

averring that the process included peer review. A. 52–53. Yet

USGS failed to explain in detail whether the model runs were

shared with peer reviewers and what role, if any, they played

in the peer review process. USGS instead conflates the

deliberative process of coming to a reliable scientific result

with the approving officials’ decision to publish the urban lakes

study. See Oral Arg. Tr. 20:20–25. The Survey is widely

respected because it publishes reliable scientific research, but,

for FOIA purposes, the decision to publish a paper and the

underlying scientific determination are not one and the same.

Without more, we cannot find that USGS has carried its burden

to explain the model runs’ role in its decision-making process.

The “more” we are looking for requires USGS to establish

how its decision to publish the urban lakes study was reached;

what information was shared with reviewers, internal and

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external; whether drafts reviewed by agency officials making

the publication decision included the underlying model run

data; and how the exploratory data runs influenced the decision

to publish or the form the final publication would take.

Without this information, USGS has “failed to supply us with

even the minimal information necessary to make a

determination.” See Coastal States, 617 F.2d at 861. We

remind USGS that “the burden is on them to establish their

right to withhold information from the public and they must

supply the courts with sufficient information to allow us to

make a reasoned determination that they were correct.” Id.

B.

USGS also failed to prove beyond dispute that the model

runs are deliberative. Our deliberativeness inquiry “focuse[s]

on whether disclosure of the requested material would tend to

discourage candid discussion within an agency.” Petroleum

Info. Corp., 976 F.2d at 1434 (internal quotations omitted). We

ask whether the document is “so candid or personal in nature

that public disclosure is likely in the future to stifle honest and

frank communication,” Coastal States, 617 F.2d at 866, “and

thereby undermine the agency’s ability to perform its

functions,” Dudman, 815 F.2d at 1568. USGS failed to

establish how or why disclosure of the model runs would chill

scientists’ use of exploratory model runs in the future or impact

the accuracy or efficiency of the Survey’s operations.

The agency’s affidavits contain no explicit statement that

disclosure will harm the agency’s decision-making. At oral

argument agency counsel could not point to a similar claim, nor

did we find one in the record. Cf. Oral Arg. Tr. 24:9–10

(USGS’s counsel conceded he was “not sure if” the agency

affidavits “explicitly say that [release] would change the way

they do their business”). We find only claims that releasing the

13

model runs will enable criticism of USGS. A. 27, 49. But

criticism is not a recognized harm against which the

deliberative process privilege is intended to protect. Granted,

USGS argues that release could cause public confusion, and we

have acknowledged misperception of agency positions as a

ground for withholding deliberative materials. See Judicial

Watch, Inc. v. Dep’t of Def., 847 F.3d 735, 739 (D.C. Cir.

2017). But the privilege’s “‘ultimate aim’ is to ‘prevent injury

to the quality of agency decisions.’” Petroleum Info. Corp.,

976 F.2d at 1434 (quoting NLRB v. Sears, Roebuck & Co., 421

U.S. 132, 151 (1975)). And it is also clear from our—and

Supreme Court—precedent that we are obligated to construe

the exemption narrowly and focus on whether disclosure will

harm intra-agency candor and efficiency. Id. at 1434–35; see

also Milner, 562 U.S at 565 (“[FOIA’s] exemptions are

explicitly made exclusive, and must be narrowly construed.”

(internal citations and quotations omitted)); U.S. Fish &

Wildlife Serv., 141 S. Ct. at 785 (“To encourage candor, which

improves agency decisionmaking, the privilege blunts the

chilling effect that accompanies the prospect of disclosure.”).

USGS does not say it will and does not explain how, if these

model runs are disclosed, scientists will cease to conduct model

runs in the future or do them differently.

To the contrary, PCTC introduced evidence that disclosure

of the model runs will not impede or impair the scientists’ work

going forward. The Director of PCTC introduced, in her

affidavit, an unrebutted excerpt from Nature Magazine’s

conditions of publication, which require authors to “make

materials, data, code, and associated protocols promptly

available to readers without undue qualifications.” A. 168.

Although it is not clear that other scientific journals, or even

Nature, would expect the authors to release all 200 model runs,

the Survey cannot meet its burden of justifying the categorical

withholding of all unpublished model runs given this

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unrebutted evidence. And at oral argument the Survey’s

attorney admitted that performing preliminary model runs “is

quite standard.” Oral Arg. Tr. 22:23–24. Consequently, we

hesitate to presume that USGS scientists will be discouraged

from performing these standard calibrations in the future in a

way that would harm the agency’s decision-making. For the

same reason, it is not obvious that disclosure would result in

the same harm to agency decision-making as in Dudman, 815

F.2d at 1569 (finding that publication of draft agency history

would discourage the candid exchange of ideas), and Russell v.

Dep’t of the Air Force, 682 F.2d 1045, 1048 (D.C. Cir. 1982)

(same).

Nor do we find these model runs exactly analogous to peer

review comments. See Formaldehyde Inst. v. Dep’t of Health

& Human Servs., 889 F.2d 1118, 1120, 1123–25 (D.C. Cir.

1989). In Formaldehyde we found reviewers’ comments that

contained “advice, constructive criticism and guidance with

respect to revision” of a scientific study submitted for

publication protected by the privilege where the “undisputed

factual record clearly establishe[d] that [agency]

personnel . . . must regularly rely on the comments of expert

scientists to help them evaluate the readiness of agency work

for publication.” Id. at 1124–25. That record also contained

“unrefuted evidence” that release of reviewers’ comments

“would very likely have a chilling effect on either the candor

of potential reviewers of government-submitted articles or on

the ability of the government to have its work considered for

review at all.” Id. at 1125. Those findings supported the

inference that “a government author is likely to be less willing

to submit her work to a refereed journal at all if critical reviews

could come to light somewhere down the line” resulting “in the

publication of inferior work in (presumably) inferior and less

widely circulated journals.” Id. Because there is no evidence

here that scientists will cease to run thorough and searching

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exploratory analyses, we cannot follow the same chain of

inferences we did in Formaldehyde, where we could easily see

the detrimental effects of disclosure.

We find sufficient uncertainty about whether this type of

data is ordinarily disclosed, or whether there is an expectation

that it will not be disclosed, or what impact it would have if is

disclosed, to rule for USGS at the summary judgment stage.

C.

The absence of evidence establishing that the requested

model runs are protected from disclosure amounts to the

agency’s failure to establish that it is entitled to judgment as a

matter of law. See FED. R. CIV. P. 56(a). We leave to the

District Court the decision how to proceed. Generally

speaking, discovery is rarely appropriate in FOIA cases, In re

Clinton, 970 F.3d 357, 364 (D.C. Cir.), on reh’g, 973 F.3d 106

(D.C. Cir. 2020), cert. denied sub nom. Jud. Watch, Inc. v.

Clinton, No. 20-1051, 2021 WL 1163766 (U.S. Mar. 29, 2021),

and the preferred approach, if possible, is to resolve the lawsuit

without discovery and by summary judgment. If the District

Court believes that it can resolve this case for one side or the

other with supplemental affidavits and further summary

judgment briefing, it should do so. This strikes us as the

prudent course where it allows the District Court to resolve a

contested FOIA request most efficiently. FED. R. CIV. P. 1

(“[These rules] should be construed, administered, and

employed by the court and the parties to secure the just, speedy,

and inexpensive determination of every action and

proceeding.”).

Of course, summary judgment is not barred merely

because “the parties’ affidavits disagree on the probable

consequences of a disclosure,” Alyeska Pipeline Serv. Co. v.

EPA, 856 F.2d 309, 313 (D.C. Cir. 1988), but if the undisputed

16

material facts “are susceptible to divergent inferences bearing

upon an issue critical to the disposition of the case, summary

judgment is not available,” id. at 314. In such an instance, the

matter can be resolved by an adjudicatory proceeding tailored

to the factual dispute in the case, such as a “paper trial” on a

stipulated evidentiary record with findings of fact and

conclusions of law set forth pursuant to Federal Rule of Civil

Procedure 52. See Wash. Post Co., 865 F.2d at 326; Sears,

Roebuck & Co. v. Gen. Servs. Admin., 553 F.2d 1378, 1382–83

(D.C. Cir. 1977).

III.

We affirm the District Court’s grant of summary judgment

to USGS with respect to the sampling location information

collected for the 2010 house dust study. Exemption Six allows

withholding of “personnel and medical files and similar files

the disclosure of which would constitute a clearly unwarranted

invasion of personal privacy.” 5 U.S.C. § 552(b)(6). It aims

“to protect individuals from the injury and embarrassment that

can result from the unnecessary disclosure of personal

information.” Dep’t of State v. Wash. Post Co., 456 U.S. 595,

599 (1982).

The study participants have a greater than de minimis

privacy interest in their addresses, household compositions,

smoking and cooking habits, and the extensive personal details

included in the questionnaires. See U.S. Dep’t of Def. v. FLRA,

510 U.S. 487, 500–01 (1994). And releasing their addresses

serves no cognizable public interest because it would shed no

additional light on the Survey’s “operations or activities,” since

USGS has already produced the questionnaires and a “means

by which to match [participants’] responses to the results of the

sample analysis.” See Nat’l Ass’n of Home Builders v. Norton,

309 F.3d 26, 33–34 (D.C. Cir. 2002) (internal quotations

17

omitted); A. 55, 148. PCTC thus has all the data it needs to

replicate the USGS scientists’ analysis of how participants’

habits may have impacted the concentration of coal tar sealant

in their homes. And in any case, PCTC’s desire to identically

replicate the study using the addresses is foreclosed given that

coal tar sealant has been outlawed in the relevant area since

2006.

Since “something, even a modest privacy interest,

outweighs nothing every time,” the District Court correctly

found the study participants’ personal information properly

withheld under Exemption Six. Nat’l Ass’n of Retired Fed.

Emps. v. Horner, 879 F.2d 873, 879 (D.C. Cir. 1989).

IV.

For the foregoing reasons, we reverse and remand to the

District Court PCTC’s claims regarding the urban lakes model

runs withheld under Exemption Five, and affirm its decision to

withhold the house dust study location information under

Exemption Six.

So ordered.