The Tenth Circuit denied environmental groups' petition to review an EPA rule that partially approved Colorado's SIP to reduce ozone pollution. The groups sought vacatur of the approval, arguing the Agency violated the CAA by approving the reasonable further progress and motor vehicle emissions budg...

The U.S. Supreme Court held, 5-4, that the CWA does not authorize EPA to include "end-result" provisions in NPDES permits, in a lawsuit concerning the Agency's issuance of a renewal permit for the city of San Francisco that added two such requirements. The city petitioned for review, arguing the req...