Document ID: ./input/supremecourt_opinions/opinions/23pdf/23a349_0813.pdf
Page Number: 34

12 

OHIO v. EPA 

BARRETT, J., dissenting 

  In sum, §7607(d)(7)(B)’s procedural bar likely forecloses 
both the failure-to-explain objection that the Court credits 
and any substantive challenge to the reasonableness of ap-
plying the FIP to a subset of the originally covered States. 

B 
  Even if applicants clear §7607(d)(7)(B)’s procedural bar, 
they face an uphill battle on the merits.  To prevail on the 
Court’s  theory,  applicants  must  show  that  EPA’s  actions 
were “arbitrary” or “capricious.”  §§7607(d)(9)(A), (D).  “The 
scope of review under the ‘arbitrary and capricious’ stand-
ard is narrow and a court is not to substitute its judgment 
for that of the agency.”  State Farm, 463 U. S., at 43.  A rule 
is arbitrary and capricious if the agency “entirely failed to 
consider  an  important  aspect  of  the  problem.”    Ibid.  (em-
phasis added).  But we will “ ‘uphold a decision of less than 
ideal  clarity  if  the  agency’s  path  may  reasonably  be  dis-
cerned.’ ”  Ibid. (quoting Bowman Transp., Inc. v. Arkansas-
Best Freight System, Inc., 419 U. S. 281, 286 (1974)).  Given 
the explanations and state-agnostic methodology apparent 
in the final rule and its supporting documentation—and the 
paucity  of  comments  specifically  raising  the  issue—EPA 
may well have done enough to justify its plan’s severability. 
  To begin, the rule and its supporting documents arguably 
make clear that EPA’s methodology for calculating cost-
effectiveness  thresholds  and  imposing  emissions  controls 
did not depend on the number of covered States.  The rule 
applied  EPA’s  longstanding  “4-step  interstate  transport 
framework” to create emissions limits that will prevent NOx 
sources in upwind States from significantly contributing to 
ozone  pollution in  downwind States.    88  Fed. Reg.  36659; 
see 42 U. S. C. §7410(a)(2)(D).  Under that framework, EPA 
(1) identifies “downwind receptors that are expected to have 
problems attaining or maintaining the NAAQS”; (2) identi-
fies which upwind States are “ ‘link[ed]’ ” to those downwind 
receptors because they contribute at least 1% of a receptor’s