"The military is beginning to check whether chemicals from its firefighting foam may have contaminated groundwater at hundreds of sites nationwide, according to the Defense Department."

"The United States has exported its first liquefied natural gas (LNG) cargo from the lower 48 states, after a tanker set sail from Cheniere Energy's Sabine Pass export terminal in Louisiana."

"U.S. authorities have asked the German carmaker Volkswagen to produce electric vehicles in the United States as a way of making up for its rigging of emission tests, the German newspaper Welt am Sonntag reported."

"Volkswagen internal memos and emails suggest that company executives pursued a strategy of delay and obfuscation with United States regulators after being confronted in early 2014 with evidence that VW diesel vehicles were emitting far more pollutants than allowed."

"After a runaway oil train killed 47 people in Lac-Megantic, Quebec, just miles from the Maine border in 2013, Mainers demanded to know more about the state’s railways."

"A new report finds the railroad cars that transport the toxic gas around the United States are vulnerable to accidents and sabotage."

"After more than six years of negotiations, the global aviation industry agreed on Monday to the first binding limits on carbon dioxide emissions, tackling the fastest-growing source of greenhouse gas pollution."

"Europe and the United States tried to bridge differences over emissions standards for aircraft on Sunday as global aviation leaders prepared to adopt new rules that could affect Boeing Co and Airbus Group's production of the largest jetliners and freighters."