Wildfires churning out dense plumes of smoke as they scorch part of the U.S. West Coast have exposed more than 8 million people to hazardous pollution levels.
A report issued Thursday by watchdog groups Environment Montana and Frontier Group says that Western Sugar Cooperative in Billings exceeded its permitted limit for release of materials including toxic pollutant ammonia nitrogen, E. coli and fecal coli-form into the Yellowstone River 56 times during a 21-month period...