APPENDIX

5a
and five points along the Sam Downs Road where the
Defendants use ditches, culverts, and channels to
collect and then discharge stormwater runoff. Each
sample contained significant amounts of sediment.
None of the Defendants has sought or received
NPDES permits for these discharges into the
streams and rivers. NEDC brought suit under the
citizen suit provision of the CWA, 33 U.S.C.
§ 1365(a), which provides that “any citizen may
commence a civil action on his own behalf ... against
any person” alleged to be in violation of the CWA.
NEDC claims that Defendants have violated the
CWA by not obtaining NPDES permits. On March 1,
2007, the district court dismissed NEDC’s complaint
with prejudice under Federal Rule of Civil Procedure
12(b)(6) for failure to state a claim. NEDC has timely
appealed.
II. Subject Matter Jurisdiction
In the original version of our opinion, we did not
discuss our subject matter jurisdiction. None of the
parties to the suit had raised an objection to subject
matter jurisdiction. In an amicus brief, however, the
United States had contended that the challenged
Silvicultural Rule was unambiguous and that, as a
consequence, citizen-suit jurisdiction under 33 U.S.C.
§ 1365(a) was improper. Instead, the United States
had argued, the suit should have been brought under
33 U.S.C. § 1369(b). A defect in subject matter jurisdiction
is, of course, not waivable.
Without discussing subject matter jurisdiction,
we held on the merits that the Silvicultural Rule is
ambiguous. After we published our opinion, one of
our colleagues asked us to discuss our subject matter
jurisdiction. We asked for supplemental briefing. In