"Federal appeals court judges appeared skeptical today about U.S. EPA's argument that it is required under the Clean Air Act to use a less stringent implementation regime for fine particulates than it is for more coarse -- and less dangerous -- particles."

"Carbon dioxide has been vilified for decades as a driver of global warming. A new study finds signs that CO2, exhaled in every breath, can exert an equally worrisome threat -- impaired cognition -- in nearly every energy-efficient classroom, meeting hall or office space."

"Honeywell International Inc said Tuesday it could take nine to 12 months to upgrade the Metropolis Works uranium conversion facility in Southern Illinois to ensure it could withstand a strong earthquake or tornados."

"With all of the theatrics of a town hall-style presidential debate [Tuesday] night, President Obama and Republican challenger Mitt Romney sparred over who is the bigger 'Mr. Oil' and 'Mr. Gas' amid declining U.S. energy imports and rising domestic production."

Residents of a neighborhood just east of Hialeah have been experiencing cancer and asthma in what they see as unusual amounts. They live in an area with many industries that pollute with toxic dust and chemicals. Those companies often flout enforcement efforts by the county.

"About 67 percent of Americans believe temperatures are rising, marking a slow but persistent rebound from the 2009 freefall in public opinion around climate change. Belief in warming now almost matches its pre-tumble level of four years ago, a new poll finds."

"A host of startup companies are pursuing new technologies that they claim will soon lead to large-scale commercialization of biofuels made from algae. But questions remain about the viability and environmental benefits of what its developers are calling 'green crude.'"

"Under fire for dumping toxic pollution into Lake Michigan, owners of the last coal-powered steamship on the Great Lakes promised four years ago they would eliminate its murky discharges in time for the 2012 sailing season."

"A Duke University-led study of coal ash contaminants, published Monday, found high levels of toxic arsenic in Mountain Island Lake."

"In February 2011, a resident of a western Pennsylvania town noticed that her water was black and 'had a very strong metallic odor.'"