"In the months before last week's deadly fertilizer plant explosion in Texas, U.S. government watchdogs criticized federal oversight of facilities that make or store dangerous chemicals."

"COPEMISH, Mich. — A team led by a nurseryman from northern Michigan and his sons has raced against time for two decades, snipping branches from some of the world's biggest and most durable trees with plans to produce clones that could restore ancient forests and help fight climate change."

"Wisconsin Power & Light Co. and three other utilities will spend $1.2 billion to clean up coal-fired power plants and shut down older plants under a settlement announced Monday with federal regulators."

"Underfunded agency faces the challenge of finding answers to key questions: When did Exxon's pipeline rupture and when did the company learn of the spill?"

"CHARLESTON, W.Va. -- Scientists backed by a $15 million industry-funded research project are picking apart -- and trying to disprove -- a series of studies that found coalfield residents near mountaintop-removal mining operations face greater risks of serious illness and premature death."

"Nearly 800 hazardous waste sites are located in Erie, Niagara and Cattaraugus counties, and the majority of them are a threat to the largest source of fresh water in the world – the Great Lakes."

"CLEARWATER -- Despite warnings from scientists, rising sea levels still seem little more than a distant, imperceptible threat, a phenomenon whose change is measured in centimeters over decades."

"RONAN, Mont. -- In a place where the lives and histories of Indian tribes and white settlers intertwine like mingling mountain streams, a bitter battle has erupted on this land over the rivers running through it."