Authors looked at pollution from highways, coal-fired power plants, hog farms, other sources.
Comment period continues through Aug. 9; Samish Island residents concerned.
Weather, emissions combine to form a smothering blanket of air pollution.
Automaker agrees to pay $4.3 million in penalties, but actual costs could be much higher.
State agencies have taken separate actions against U.S. Golden Eagle Farms in Skagit County.
Skagit River watershed glaciers have lost enough ice to equal the size of the city of Mount Vernon.
About 300 million children live in areas with “toxic” levels of air pollution, according to new research from the United Nations Children’s Fund.
The settlement over cheating on vehicle-emissions tests is the largest auto-scandal settlement in the nation’s history.
Emission reductions are required to start Jan. 1.
Large industrial emitters must reduce carbon emissions over time.