Montana Department of Environmental Quality

State environmental regulators have denied a petition to list the Big Hole River as impaired. Water conservation groups worry this will continue to harm the river, and its aquatic life.

Legislators have voted forward bills on property tax relief, Medicaid expansion, judicial oversight and more.

The state Department of Environmental Quality is considering whether a more intensive effort is needed to clean up arsenic contamination at Arrowstone Park in Deer Lodge.

A landmark Montana Supreme Court decision last year struck down laws passed by Republicans that would have changed Montana's bedrock environmental policy. Now, GOP lawmakers have introduced a suite of bills to undo the court's ruling.

Gov. Gianforte names new Department of Agriculture director. Montana's DEQ to develop emissions reduction roadmap

The Montana Supreme Court upheld the water use permit for a controversial proposal for a copper mine near the Smith River. The mine is now fully permitted to be built.

The Montana Supreme Court Friday affirmed a lower court ruling finding that state environmental regulators failed to assess the greenhouse gas emissions associated with a fossil fuel power plant.

State environmental regulators are expanding their ability to measure air quality, particularly in rural communities. The latest addition to their network is a permanent monitor in Glasgow.

State environmental regulators have proposed changes to how they assess pollutants that can kill aquatic species in rivers and streams. Environmental groups worry the methods aren’t scientifically sound.

Schools kept students inside for recess and athletics Monday as a thick blanket of smoke smothered western and central Montana. New research aims to better understand air quality inside schools.