United States v. DTE Energy Co., 711 F.3d 643

Clean Air Act NSR requires permits for major modifications; preconstruction projections determine permit need.
Regulatory history: 1992 actual-to-future-actual test; 2002 actual-to-projected-actual test with reasonable-possibility recordkeeping.
Remand in 2007 led to regulations defining 'reasonable possibility' and requiring monitoring/reporting when project may cause significant emissions.
DTE Monroe Unit #2 project (2010) projected post-change emissions increases; claimed under demand growth exclusion; Michigan DEQ did not act.
EPA issued a violation notice (June 2010); district court granted summary judgment for DTE, rejecting preconstruction enforcement.
EPA appeals challenging district court’s reading; majority reverses and remands to allow enforcement of preconstruction projections under NSR.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Whether EPA may challenge a preconstruction projection before post-construction data.	EPA can enforce projections to ensure compliance with NSR rules.	District court correctly held no preconstruction enforcement unless post-construction data show a violation.	EPA may challenge preconstruction projections; remanded for proceedings consistent with this opinion.
Whether the project-and-report scheme operates as a prior-approval regime or a project-and-report framework.	Scheme allows enforcement without preapproval; projections must be made per regulations.	Preconstruction enforcement should be unavailable until post-construction data prove a violation.	Not a prior-approval scheme; EPA may enforce projections under the project-and-report framework.

New York v. EPA, 413 F.3d 3 (D.C.Cir.2005) (remand over NSR recordkeeping and reasonable-possibility concerns)
Wisconsin Electric Power Co. v. Reilly, 893 F.2d 901 (7th Cir.1990) (actual-to-potential test invalid for power plants)
Alaska Dept. of Envtl. Conservation v. EPA, 540 U.S. 461 (Supreme Court 2004) (EPA supervisory authority over NSR construction/modification)