Anglers of the Ausable Inc v. Dept of Environmental Quality, 796 N.W.2d 240

Anglers of the Au Sable, Inc., Mayer Family Investments, LLC, and Nancy A. Forcier Trust sued DEQ and Merit Energy Company in Michigan Supreme Court proceedings.
The Court granted rehearing, vacated the December 29, 2010 opinion, and dismissed the appeal as moot, citing that Merit had quit-claimed its easement and DEQ no longer permitted discharge into Kolke Creek or Au Sable River.
DEQ attested that there no longer exists any possibility of surface water discharge to Kolke Creek or the Au Sable River, and Merit now uses alternative means to dispose of water.
The Court of Appeals’ opinion was vacated, and mootness arguments were central to the reconsideration.
Several justices filed concurring or dissenting statements addressing mootness doctrine, rehearing standards, and the effect on precedent and public interest.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Whether the case is moot and subject to dismissal	Anglers argues mootness remains because rights persist, so review is proper.	DEQ/Merit contend changed circumstances render mootness and permit dismissal.	Case vacated and dismissed as moot
Whether rehearing was proper given changes in Court membership	Rehearing should be considered on merits, not depend on new makeup.	Court may grant rehearing discretionarily when warranted by law and facts even with new members.	Rehearing granted; opinion vacated
What standard governs motions for rehearing in this Court	Existing rules and precedent support reviewing the merits on rehearing.	Standard depends on Court rules; MCR 2.119(F)(3) guidance applies in practice.	Court concludes rehearing appropriate under applicable rules (not strictly limited to new arguments)
Whether vacating the mootness disposition aligns with Preserve the Dunes and public interest	Preserve the Dunes should be respected; not mootness-based reversal.	Mootness was decided inconsistently; rehearing should restore the correct precedent.	Yes; rehearing vacates prior mootness ruling and aligns with Preserve the Dunes

Anglers of the AuSable, Inc v Dep't of Environmental Quality, 488 Mich 69 (2010) (mootness and Preserve the Dunes context in Michigan water law)
United States v Munsingwear, Inc, 340 US 36 (1950) (vacatur of lower court judgment when case becomes moot)
City of Erie v Pap's AM, 529 US 277 (2000) (importance of jurisdiction and mootness where public interest persists)
United States Fidelity Ins & Guar Co v Michigan Catastrophic Claims Ass'n (On Rehearing), 484 Mich 1 (2009) (discusses rehearing standards and changes in composition)
Preserve the Dunes, Inc v Dep’t of Environmental Quality, 471 Mich 508 (2004) (established framework for MEPA-related precedent; mootness considerations)