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Tripoli Rocketry Ass'n v. Bureau of Alcohol, Tobacco, Firearms, & Explosives

Court: Court of Appeals for the D.C. Circuit
Date filed: 2006-02-10
Citations: 437 F.3d 75, 369 U.S. App. D.C. 327
Copy Citations
58 Citing Cases
Combined Opinion
 United States Court of Appeals
         FOR THE DISTRICT OF COLUMBIA CIRCUIT



Argued January 10, 2006            Decided February 10, 2006

                         No. 04-5453

         TRIPOLI ROCKETRY ASSOCIATION, INC. AND
          NATIONAL ASSOCIATION OF ROCKETRY,
                      APPELLANTS

                              v.

      BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND
                    EXPLOSIVES,
                     APPELLEE


        Appeal from the United States District Court
                for the District of Columbia
                      (No. 00cv00273)



    Joseph R. Egan argued the cause for appellants. With him
on the briefs were Martin G. Malsch, Robert J. Cynkar, and
Charles J. Fitzpatrick.

     Jane M. Lyons, Assistant U.S. Attorney, argued the cause
for appellee. With her on the brief were Kenneth L. Wainstein,
U.S. Attorney, and Michael J. Ryan, Assistant U.S. Attorney. R.
Craig Lawrence, Assistant U.S. Attorney, entered an
appearance.
                                2

   Before: TATEL and GARLAND, Circuit Judges, and
EDWARDS, Senior Circuit Judge.
   Opinion for the Court filed by Senior Circuit Judge
EDWARDS.
     EDWARDS, Senior Circuit Judge: Appellants Tripoli
Rocketry Association and National Association of Rocketry are
non-profit organizations whose members are hobby rocket
enthusiasts. They challenge the Bureau of Alcohol, Tobacco,
Firearms & Explosives’ (“ATFE”) refusal to alter its
classification of ammonium perchlorate composite propellant
(“APCP”) as an “explosive” for purposes of 18 U.S.C. § 841(d)
(2000). (ATFE is currently charged with administering the
statute at issue. Until recently, those duties rested with the
Bureau of Alcohol, Tobacco & Firearms (“ATF”), and, before
that, with the Internal Revenue Service. For the sake of
simplicity, we will refer only to “ATFE,” except when quoting
material that refers to one of its predecessors.)
     APCP is commonly used as fuel in hobby rockets, and
classification as an explosive imposes regulatory controls on the
handling of APCP by appellants’ members. The statutory
definition of “explosive” encompasses materials whose “primary
or common purpose” is to “function by explosion.” ATFE
determines whether a material fits this definition by
characterizing the speed at which the material burns: materials
with the fastest burn rates detonate, the slowest ones burn, and
substances in between deflagrate. In other words, under
ATFE’s characterization, a substance that deflagrates burns
more rapidly than something that simply burns (like paper or a
candle wick), but less rapidly than something that detonates (like
dynamite). And ATFE treats a material as explosive if it
functions by detonation or deflagration.
     Appellants challenge ATFE’s determination that APCP
deflagrates. Appellants contend that ATFE’s determination was
                                3

arbitrary and capricious under the Administrative Procedure Act
(“APA”), 5 U.S.C. § 706(2)(A) (2000), because there is no
evidence in the record supporting the conclusion that APCP
functions by deflagration and there is some evidence in the
record suggesting a contrary conclusion. In response, ATFE
points to evidence relating to the properties of “rocket
propellants.” ATFE also argues that, in a case of this nature –
involving the agency’s expertise in deciding a highly technical
question – the court should defer to ATFE’s judgment.
     This court routinely defers to administrative agencies on
matters relating to their areas of technical expertise. We do not,
however, simply accept whatever conclusion an agency proffers
merely because the conclusion reflects the agency’s judgment.
In order to survive judicial review in a case arising under
§ 7006(2)(A), an agency action must be supported by “reasoned
decisionmaking.” Allentown Mack Sales & Serv., Inc. v. NLRB,
522 U.S. 359, 374 (1998) (quoting Motor Vehicle Mfrs. Ass’n of
the United States, Inc. v. State Farm Mut. Auto. Ins. Co., 463
U.S. 29, 52 (1983)). “Not only must an agency’s decreed result
be within the scope of its lawful authority, but the process by
which it reaches that result must be logical and rational. Courts
enforce this principle with regularity when they set aside agency
regulations which, though well within the agencies’ scope of
authority, are not supported by the reasons that the agencies
adduce.” Id. The problem in this case is that ATFE’s
explanation for its determination that APCP deflagrates lacks
any coherence. We therefore owe no deference to ATFE’s
purported expertise because we cannot discern it. ATFE has
neither laid out a concrete standard for classifying materials
along the burn-deflagrate-detonate continuum, nor offered data
specific to the burn speed of APCP when used for its “common
or primary purpose.” On this record, the agency’s decision
cannot withstand judicial review. We therefore remand the case
for further consideration.
                               4

                       I. BACKGROUND
     Title XI of the Organized Crime Control Act of 1970
(“OCCA”) regulates the manufacture, distribution, and storage
of explosive materials. See Pub. L. No. 91-452, § 1102, 84 Stat.
952 (1970) (codified at 18 U.S.C. §§ 841-848 (2000)). Under
the statute, “explosive materials” include “explosives, blasting
agents, and detonators,” 18 U.S.C. § 841(c); and, for purposes
of the provisions at issue here, “explosives” include:
    any chemical compound mixture, or device, the primary or
    common purpose of which is to function by explosion; the
    term includes, but is not limited to, dynamite and other high
    explosives, black powder, pellet powder, initiating
    explosives, detonators, safety fuses, squibs, detonating cord,
    igniter cord, and igniters.
18 U.S.C. § 841(d).
     Until recently, the statute required the Secretary of the
Treasury or his delegate to compile an explosives list, 18 U.S.C.
§ 841(d), (k) (2000), but this responsibility was reassigned by
the Homeland Security Act, Pub. L. No. 107-296 § 1112(e), 116
Stat. 2135, 2276 (2002). The current version of OCCA requires
the Attorney General to “publish and revise at least annually in
the Federal Register” the explosives list, including “any
additional explosives which he determines to be within the
coverage of this chapter.” 18 U.S.C. § 841(d) (Supp. 2002).
Potential users must obtain a license or permit from ATFE to
import, manufacture, or deal in explosive materials. 18 U.S.C.
§ 842(a); see also 18 U.S.C. § 843 (2000) (outlining
requirements for obtaining licenses). Users are also subject to
certain requirements governing the manufacture, storage,
transportation, transfer, and sale of explosive materials. 18
U.S.C. § 842(b)-(k). Violators of these statutory provisions face
the possibility of criminal sanctions. 18 U.S.C. § 844(a)(1), (b)
(2000).
                                5

     It has always been the case that the agency regulations
implementing these OCCA requirements have exempted, inter
alia, “propellant actuated devices . . . manufactured, imported,
or distributed for their intended purposes.” See 27 C.F.R.
§ 555.141(a)(8) (2005) (current exemption); 26 C.F.R.
§ 181.141(i) (1972) (initial exemption). “Propellant actuated
device” is defined to mean: “Any tool or special mechanized
device or gas generator system which is actuated by a propellant
or which releases and directs work through a propellant charge.”
27 C.F.R. § 555.11 (2005).
    Appellants claim that there is no known purpose for using
APCP other than as a rocket propellant. According to
appellants, hobby rocket enthusiasts use APCP in one of two
fashions. The material is sometimes shipped already in a rocket
motor and then used once in a model rocket. Alternatively, the
material is shipped as part of a reloadable motor kit in the form
of propellant modules, from which the rocket enthusiast
assembles the motor. Upon ignition, APCP in rocket motors is
designed to release its energy in a controlled, predictable, and
focused fashion to power the flight of the hobby rocket.
     APCP was placed on the first “Explosives List” issued in
1971, see Commerce in Explosives, 36 Fed. Reg. 658, 675 (Jan.
15, 1971), and has remained on the list ever since, see
Commerce in Explosives; List of Explosive Materials, 70 Fed.
Reg. 73,483, 73,484 (Dec. 12, 2005). In April 1994, ATFE sent
a letter to Aerotech, Inc., a company that produces hobby
rockets, replying to the company’s inquiries regarding the
regulatory constraints affecting its business. ATFE explained
that “[d]uring the early 1970's when [ATFE] was assigned the
responsibility of enforcing the Federal explosives laws, it was
clear that [the agency] did not intend to regulate toy model
rockets which did not constitute a public safety hazard,” but that
“[i]t is also clear that ammonium perchlorate composite
propellants are explosives since they have been on the
                                6

explosives list since the first list was published in 1971.” Letter
from ATFE to Gary C. Rosenfield, President, Aerotech, Inc.
(Apr. 20, 1994) at 1, Joint Appendix (“J.A.”) 106. The agency
declared that the exemption for propellant actuated devices
applies only to rocket motors that, inter alia, contain no more
than 62.5 grams of propellant, thus excluding APCP from
exemption. Id. ATFE also announced that, while fully
assembled rocket motors could qualify for the exemption, rocket
propellent prior to assembly cannot.
     Appellants challenged this decision in a September 7, 1999
letter to ATFE, asserting that APCP does not function by
explosion and, therefore, ATFE lacked statutory authority to
regulate the material as an explosive. Appellants also argued
that any type of rocket motor, regardless of the amount of fuel,
is a propellant actuated device and therefore exempt from
regulation. Finally, appellants criticized what they considered
procedural defects in the promulgation of the explosives list,
arguing that ATFE had never enunciated any “criteria (specific
or general) for determining why the listed materials were
‘explosives,’ ‘detonators,’ or ‘blasting agents’” and that the
“absence of any criteria by which to make a determination that
APCP should be on the list . . . renders the explosives list both
over-inclusive and under-inclusive.” Letter From Appellants’
Counsel to ATFE (Sept. 7, 1999) at 12-13, J.A. 99-100.
     In response, ATFE sent appellants a letter denying their
request that APCP be removed from the explosives list. In this
letter, ATFE declared that, because it functions by deflagration,
APCP is an explosive:
    An item can “function by explosion” not only by
    detonating, but also by deflagrating. While APCP does not
    generally function by detonation, it most definitely
    functions by deflagration; therefore, APCP is properly
    deemed by ATF to “function by explosion” and is properly
    classified as an “explosive.”
                                 7

Letter from ATFE to Appellants’ Counsel (Dec. 22, 2000) at 2
(“December 2000 Letter”), J.A. 73. The agency first noted that
some of the substances specifically itemized as explosives in
§ 841(d) burn too slowly to be characterized as detonating, thus
providing “a clear manifestation of Congress’s intention that
both detonating and deflagrating ‘compounds, mixtures, and
devices’ are to be considered” explosives. Id. at 4, J.A. 75. The
agency further stated that treating deflagrating materials as
explosives places the statutory definition in line with the
scientific definition, which ATFE recapitulated as follows:
    While deflagration produces a reaction that is slower than
    the reaction achieved through detonation, the deflagration
    reaction is much faster than the reaction achieved by what
    is more commonly associated with burning (such as with
    the burning of a candle or with the burning that occurs in a
    typical building- or forest-fire).
Id. (emphasis added). The agency never defined the threshold
for “much faster,” but it did cite a pyrotechnics text to further
articulate the relative measurements that distinguish various
forms of combustion:
    Dr. Conkling indicates that the approximate reaction
    velocity associated with detonation (he cites as examples
    dynamite and TNT) is greater than one kilometer per
    second; he indicates that the approximate reaction velocity
    associated with deflagration (he cites as examples rocket
    propellants, and confined black powder) is in the range of
    “meters per second” [typically, the speed of deflagration
    will be less than 326 meters per second – the velocity of
    sound]; and he indicates that the approximate reaction
    velocity associated with the more-common [sic] type of
    burning is in the order of “millimeters per second.”
Id. at 5 n.5, J.A. 76 (first alteration in original) (quoting JOHN A.
CONKLING, CHEMISTRY OF PYROTECHNICS 2 (1985)).
                                8

     ATFE’s letter concludes that “[u]pon ignition . . . APCP
deflagrates,” because it “burns with oxidation taking place at a
rate slower than the oxidation rate in a detonation (though at a
rate much faster than is associated with typical burning).” Id. at
5, J.A. 76. To bolster this determination, the agency quoted the
National Fire Protection Association’s definition of “propellant”
as “an explosive material which normally functions by
deflagration,” and claimed that other expert organizations adhere
to similar definitions. Id. at 6-7, J.A. 76-77 (quoting NATIONAL
FIRE PROTECTION ASSOCIATION, FIRE PROTECTION HANDBOOK
5-69 (16th ed. 1986)). After finding that APCP deflagrates,
ATFE rejected appellants’ argument that rocket motors are
propellant actuated devices and thus exempt from regulation.
     Appellants brought suit against ATFE in the United States
District Court for the District of Columbia, challenging the
agency decisions rendered in the December 2000 Letter.
Appellants contended that § 841(d)’s definition does not extend
to deflagrating materials and that, in any event, APCP does not
function by deflagration. Appellants also objected to the
agency’s decision to deny sport rocket motors an exemption as
propellant actuated devices. And they contested ATFE’s
decision to establish thresholds for the regulation of certain
APCP rocket motors based upon their weight, design, and
intended use without first affording the public an opportunity to
comment on those thresholds.
     On March 19, 2004, the District Court issued an opinion
addressing the parties’ cross motions for summary judgment.
Tripoli Rocketry Ass’n, Inc. v. Bureau of Alcohol, Tobacco,
Firearms & Explosives, 337 F. Supp. 2d 1 (D.D.C. 2004). The
District Court noted that “a court should review scientific
judgments of an agency ‘not as the chemist, biologist or
statistician that we are qualified neither by training nor
experience to be, but as a reviewing court exercising our
narrowly defined duty of holding agencies to certain minimal
                                9

standards of rationality.’” Id. at 8 (quoting Ethyl Corp. v. EPA,
541 F.2d 1, 36 (D.C. Cir. 1976) (en banc)). After reviewing the
statute and the record, the District Court “conclude[d] that the
ATF’s decision that APCP is a deflagrating explosive is
permissible.” Id. at 9. The District Court then granted summary
judgment to the agency on the issue of whether APCP is a
deflagrating explosive. However, the trial court invalidated
ATFE’s decision that sport rocket motors are not propellant
actuated devices, because it was rendered without
notice-and-comment rulemaking as required by the APA and
OCCA. Id. at 13. The court also noted that the agency had
commenced rulemaking on the disputed non-exempt status of
sport rocket motors that use more than 62.5 grams of APCP. Id.
at 14-15. The District Court delayed issuing any final judgment
on these two matters pending the agency’s completion of the
notice-and-comment rulemakings.
    On October 21, 2004, appellants filed a motion requesting
the District Court to enter a final judgment, pursuant to Federal
Rule of Civil Procedure 54(b), on the issue of whether APCP is
properly classified as an explosive. The District Court
concluded that there was no just reason for delaying a final
judgment and granted appellants’ motion. See Tripoli Rocketry
Ass’n, Inc. v. Bureau of Alcohol, Tobacco, Firearms &
Explosives, CA No. 00-273 (D.D.C. Dec. 21, 2004). Appellants
then filed a timely appeal.
                         II. ANALYSIS
     This court reviews the District Court’s grant of summary
judgment de novo. Egan v. U.S. Agency for Int’l Dev., 381 F.3d
1, 3 (D.C. Cir. 2004). Appellants raise one issue in this appeal:
whether the administrative record supports ATFE’s decision to
characterize APCP as a deflagrating material, and thus an
explosive under § 841(d). Appellants do not challenge the
District Court’s decision that deflagrating materials are properly
defined as explosives under the statute. See Appellants’ Br. at
                               10

17 (“[F]or purposes of this appeal it is assumed that a substance
whose primary or common purpose is to function by
deflagration is an ‘explosive.’”). The simple question before
this court is whether ATFE’s determination that APCP functions
by deflagration is “arbitrary, capricious, an abuse of discretion,
or otherwise not in accordance with law,” 5 U.S.C. § 706(2)(A).
     ATFE’s decision cannot be sustained on the basis of the
current administrative record. The agency has never provided
a clear and coherent explanation for its classification of APCP.
We do not mean to suggest that the record mandates a
conclusion contrary to the agency’s. Rather, we simply find that
ATFE has never articulated the standards that guided its
analysis. “To survive review under the ‘arbitrary and
capricious’ standard, an agency must ‘examine the relevant data
and articulate a satisfactory explanation for its action including
a rational connection between the facts found and the choice
made.’” PPL Wallingford Energy LLC v. FERC, 419 F.3d 1194,
1198 (D.C. Cir. 2005) (quoting State Farm, 463 U.S. at 43
(internal quotation marks omitted)). ATFE has not met this
standard.
     The fatal shortcoming of ATFE’s position is that it never
reveals how it determines that a material deflagrates. Scientific
sources reproduced in the record suggest that the defining
characteristic is burn velocity, but the agency never defines a
range of velocities within which materials will be considered to
deflagrate. We understand that it may be necessary for AFTE
to define a range flexibly, accounting for gray areas where
expert discretion is necessary to characterize a particular
substance. But, as a reviewing court, we require some metric for
classifying materials not specifically enumerated in the statute,
especially when, as here, the agency has not claimed that it is
impossible to be more precise in revealing the basis upon which
it has made a scientific determination. Yet, in this case, ATFE
                               11

has provided virtually nothing to allow the court to determine
whether its judgment reflects reasoned decisionmaking.
     AFTE’s unbounded relational definition – i.e., “the
deflagration reaction is much faster than the reaction achieved
by what is more commonly associated with burning” – does not
suffice, because it says nothing about what kind of differential
makes one burn velocity “much faster” than another. Ten
millimeters per second? A hundred? A thousand? The record
certainly suggests that expansive differentials are possible, even
among compounds containing APCP. One source in the
administrative record describes compounds containing APCP
with burn rates ranging from 3.81 to 101.6 millimeters per
second, see 8 SEYMOUR M. KAYE, ENCYCLOPEDIA OF
EXPLOSIVES AND RELATED ITEMS 416, 433 (1978), and there is
no reason to assume that the range illustrated in the record is
even exhaustive.
     Appellants focus on the range of burn speeds illustrated in
the Encyclopedia of Explosives, arguing that “the administrative
record relied on by BATFE establishes without contradiction
that the highest burn rate for APCP rocket motors (101.6
millimeters per second) is a factor of ten below BATFE’s own
burn rate threshold for deflagration (1000 millimeters (or one
meter) per second).” Appellants’ Br. at 18-19. The agency’s
brief says virtually nothing in response to this. See ATFE’s Br.
at 13 (“Crucially, ATF did not draw the same conclusion as
appellants from the information there.”). Moreover, the burn
rates that ATFE attributes to detonation support appellants’
contention that detonation occurs at a speed representing a
different order of magnitude than the speeds reflected in the
Encyclopedia of Explosives.
     In its December 2000 Letter, ATFE suggests that the upper
bound of burn velocity for a deflagrating material is 326 meters
per second – the speed of sound. See J.A. 76-77. In the same
letter, the agency also indicates “the approximate reaction
                              12

velocity associated with detonation . . . is greater than one
kilometer per second.” Id. at 5 n.5, J.A. 76. What is one to
make of this? Obviously, there is such a wide potential for
disparity among the substances potentially classified as
explosives that the vague description “much faster” conveys no
information at all.
     ATFE’s relational definition suffers from a further
methodological flaw: it designates no points of comparison. In
order to say that one item burns “much faster” than another, one
would need to know the speed at which each item burns. But
ATFE has never pointed to evidence establishing the data points
necessary to make a comparison. For one thing, ATFE has not
stated the burn velocity of APCP in the form relevant to this
regulation. The sections of the Encyclopedia of Explosives
reproduced in the record include tables displaying the burn
speeds of several compounds containing APCP in varying
proportions. See ENCYCLOPEDIA OF EXPLOSIVES AND RELATED
ITEMS, supra, 412-16, 433-36, J.A. 199-203, 220-23. Whether
the compositions listed in those tables approximate the features
of APCP when used for its “primary or common purpose” is
entirely unclear. Similarly, whether the conditions under which
these compositions were observed match those under which
APCP commonly functions is not ascertainable. Even if the
agency had provided representative measurements for APCP, it
would still need to identify the speed at which normal burning
occurs, which it has not done.
     In defense of its unbounded comparative analysis, ATFE
insists that it had no burden to make more particularized
findings. The agency concedes that it “certainly could have
conducted experiments or otherwise researched burn rates
specific to APCP used in model rocket motors to bolster its
conclusion that APCP is capable of deflagration,” but claims
that “nothing in the OCCA or the APA required it to do so.”
ATFE’s Br. at 15. Unsurprisingly, then, rather than resting on
                                13

concrete evidence to support its judgment, ATFE simply points
to evidence relating to the properties of “rocket propellants” and
claims deference on the basis of its presumed technical expertise
and experience. The purported evidence cited by the agency
does not support its determination in this case, and the cry for
deference is hollow.
     ATFE makes three arguments, none of which are
persuasive. First, ATFE points to fire safety texts describing
“propellants” as deflagrating. See December 2000 Letter at 6-7,
J.A. 77-78. ATFE appears to assume, as a matter of simple
syllogism, that if some propellants deflagrate, and APCP is a
propellant, then APCP deflagrates. It is quite obvious that this
argument lacks a critical premise: nothing in the record shows
that all propellants burn at comparable rates. It may be that
“rocket propellant” is such a precise technical term that, once a
feature is attributed to it generally, the feature inheres in every
specific instance where the term applies. But nothing in this
record supports that conclusion. Generic statements about
“rocket propellants,” then, are not informative.
     Second, the agency seeks to invoke its institutional
expertise as a licence for making unarticulated findings. It
accuses appellants of “quarrel[ling] only over a matter of
degree,” and asserts that determining the burn speeds definitive
of deflagration “requires a level of scientific expertise and
judgment that Congress has appropriately delegated to ATF and
which is particularly poorly suited for the judiciary to second-
guess.” ATFE’s Br. at 12. As noted above, ATFE has
overstated the degree of deference owed to it by the courts in a
case arising under the APA challenging an agency action as
arbitrary and capricious. Faced with a reasoned judgment about
what conclusions to draw from technical evidence or how to
adjudicate between rival scientific theories, we will not override
an agency’s discretion. “Particularly when we consider a purely
factual question within the area of competence of an
                               14

administrative agency created by Congress, and when resolution
of that question depends on ‘engineering and scientific’
considerations, we recognize the relevant agency’s technical
expertise and experience, and defer to its analysis unless it is
without substantial basis in fact.” Fed. Power Comm’n v. Fla.
Power & Light Co., 404 U.S. 453, 463 (1972). But where an
agency has articulated no reasoned basis for its decision – where
its action is founded on unsupported assertions or unstated
inferences – we will not “abdicate the judicial duty carefully to
‘review the record to ascertain that the agency has made a
reasoned decision based on reasonable extrapolations from some
reliable evidence.’” Am. Mining Cong. v. EPA, 907 F.2d 1179,
1187 (D.C. Cir. 1990) (quoting Natural Res. Def. Council v.
EPA, 902 F.2d 962, 968 (D.C. Cir. 1990) (internal quotation
marks omitted)).       Because ATFE has articulated no
“‘satisfactory explanation for its action including a rational
connection between the facts found and the choice made,’” id.
(quoting State Farm, 463 U.S. at 43 (internal quotation marks
omitted)), it is owed no deference for the action taken in this
case on this record.
     Finally, ATFE directs our attention to the affidavit of John
A. Conkling, the author of the pyrotechnics text quoted in the
December 2000 Letter. In his affidavit, Conkling states that he
“consider[s] APCP to be a deflagrating material because it is
capable of rapid burning and can accelerate to deflagration
under pressure or confinement.” Conkling Aff. ¶ 11, J.A. 57.
For obvious reasons, this affidavit in no way aids the agency’s
cause in this case. For one thing, the affidavit was not taken
until after litigation in this case commenced. It is therefore not
a part of the agency record under review. It is well understood
in administrative law that the “focal point for judicial review
should be the administrative record already in existence, not
some new record completed initially in the reviewing court.”
Envtl. Defense Fund, Inc. v. Costle, 657 F.2d 275, 284 (D.C. Cir.
1981). The chief exception to this rule – situations “where
                                15

‘there was such a failure to explain administrative action as to
frustrate effective judicial review’” – does not apply here,
because any “new materials should be merely explanatory of the
original record and should contain no new rationalizations.” Id.
at 285 (quoting Camp v. Pitts, 411 U.S. 138, 142-43 (1973)).
Moreover, even if we were inclined to credit the affidavit, it
proves nothing of consequence in this case. Conkling merely
offers a conclusory assertion that APCP deflagrates. But this
view in no way remedies ATFE’s problem in this case, namely,
the agency’s complete absence of standards for determining
when a particular material deflagrates.
                       III. CONCLUSION
     ATFE’s authority to designate deflagrating materials as
explosives under § 841(d) is undisputed by appellants. But for
the agency to so designate a particular material, APCP, it must
establish that it is indeed a deflagrating substance. In this case,
the agency has articulated no standard whatsoever for
determining when a material deflagrates. We therefore remand
the case so that ATFE may reconsider the matter and offer a
coherent explanation for whatever conclusion it ultimately
reaches. Because ATFE’s designation of APCP as an explosive
was in place long before the present challenge, we will not
vacate the designation without first affording the agency an
opportunity to reconsider this matter. The case is hereby
remanded to the District Court with instructions to remand the
case to the agency for further consideration consistent with this
decision.