All sides are waiting for a U.S. Supreme Court ruling by the end of June in a big Clean Water Act case.

The March 31 decision is only the latest legal battle over the contentious "waters of the United States" rule.

Action is latest round in long-running battle over major minerals development in sensitive Bristol Bay watershed.

The U.S. Environmental Protection Agency has proposed a regulatory revision that would reverse a Trump-era limitation.

Industry groups praise U.S. Supreme Court order reinstating a Trump-era cutback, but environmental advocates say the action will create a lot of confusion. 

Scope of federal jurisdiction on lands near certain bodies of water is core to landowner challenge, but timing of court action will determine if Justice Stephen Breyer, a veteran of Clean Water Act rulings, can weigh in before he retires.