On March 20, 2013, the Supreme Court upheld the Environmental Protection Agency’s (“EPA”) exclusion of ditches, channels, culverts, and other stormwater conveyances associated with logging roads from permitting requirements under the National Pollutant Discharge Elimination System (“NPDES”) program established by the Clean Water Act (“CWA”). The eight-justice majority deferred to EPA’s interpretation of two CWA regulations, although a dissent by Justice Antonin Scalia argued such deference was misplaced and that the conveyances should have been regulated as “point sources” under the Clean Water Act.
The case arose when Northwest Environmental Defense Center (“NEDC”) sued several timber companies and state and local government officials, arguing that discharges of pollutants through stormwater conveyances associated with logging roads were discharges through point sources that required NPDES permits. The defendants – and EPA – argued that the conveyances were in fact exempted from the broad definition of “point source” under their interpretation of two federal regulations. One of those regulations, the Silvicultural Rule, 40 C.F.R. § 122.27(b)(1), defined certain types of conveyances associated with logging and other timber operations as “silvicultural point sources” and excluded others. The other regulation, known as the Industrial Stormwater Rule, 40 C.F.R. § 122.26(b)(14), fleshed out the nexus of two provisions of the CWA: section 1342(p)(1), which exempted discharges “composed entirely of stormwater” from CWA permitting requirements, and section 1342(p)(2)(B), which required NPDES permits for stormwater discharges “associated with industrial activity.”
NEDC argued that stormwater conveyances associated with logging roads were not excluded from the definition of silvicultural point sources under the Silvicultural Rule, and that the Industrial Stormwater Rule – which included “logging” under a list of industrial activities – could only be interpreted to mean that stormwater associated with logging roads was in fact stormwater associated with industrial activity, and thus required a NPDES permit. The trial court agreed with the defendants, but the Court of Appeals for the Ninth Circuit reversed, holding that the stormwater conveyances were in fact point sources discharging stormwater associated with industrial activity and that EPA’s regulations governing the issue were unambiguous – that is, they could not be interpreted in any manner other than the one the Ninth Circuit (and NEDC) chose. This last part of the Ninth Circuit’s holding was of particular importance, as two Supreme Court cases – Auer v. Robbins, 519 U.S. 452 (1997), and Bowles v. Seminole Rock & Sand Co., 325 U.S. 410 (1945) – have created a rule that courts will defer to an agency’s interpretation of its own regulations, so long as the interpretation is not plainly erroneous or inconsistent with the regulation itself. This principle, known as “Auer deference”, is binding upon the courts; hence if EPA’s Silvicultural Rule and Industrial Stormwater Rule were ambiguous, and EPA’s interpretation of those rules was not plainly erroneous or inconsistent with the regulations themselves, the Ninth Circuit would be obligated to defer to EPA’s interpretation and rule against NEDC.
The Supreme Court reversed the Ninth Circuit and applied Auer deference: it found that EPA’s regulations were ambiguous, the agency’s interpretation of those regulations was plausible, and that therefore the courts should defer to the agency and hold that discharges from logging roads did not need NPDES permits. In fact, the Court did not even consider for itself the issue of whether the stormwater conveyances associated with logging roads were point sources under the CWA or EPA’s implementing regulations – this despite the fact that the Court at one point said that it found NEDC’s interpretation of EPA’s rules “more plausible” than EPA’s.
A lone dissent by Justice Scalia argued – as the Ninth Circuit had – that NEDC’s interpretation of the rule was in fact the only plausible interpretation, and that the majority’s ruling suggests that it is time to reconsider whether Auer deference is an appropriate rule of law. Chief Justice Roberts wrote a concurring opinion, joined by Justice Alito, suggesting that the Court might revisit Auer deference in the future, but that it would wait for a case in which the issue was clearly presented.
The Supreme Court’s decision in Decker has important implications, not only for the question of whether stormwater discharges require NPDES permits, but for interpretation of environmental regulations more generally; for the foreseeable future, it will remain difficult to challenge an agency’s interpretation of its own regulations.
For more information on stormwater permitting issues, please contact Michael Bogin.