"Crisscrossing Michigan are more than 3,100 miles of old wrought- and cast-iron natural-gas pipelines -- the type federal regulators consider the most at risk of corrosion, cracking and catastrophic rupturing. The state's two largest utilities have replaced less than 15% of these pipelines -- 542 miles -- in the past decade."

"Rumors of Scripps begone -- geophysicist Marcia McNutt, who stepped down as head of the U.S. Geological Survey (USGS) in February, is returning to Washington, D.C., as the new editor-in-chief of Science. McNutt will take over the editorship on 1 June from Bruce Alberts, who announced his retirement last year."

"Growing environmental objections to exporting coal from Washington state and Oregon have begun to endanger the coal industry’s hope to restore its flagging fortunes by shipping much more of the embattled fossil fuel to China and India."

Next year, Ontario will become the first industrial region in North America to eliminate coal-fired electrical generation.

"The Obama administration is inching ahead with a plan that would allow wastewater from fracking to be shipped on barges, fueling a debate whether it is safer than other transportation modes or risks polluting drinking water."

"A federal agency has declared that more sick and dying sea lion pups have stranded themselves on southern California beaches so far in 2013 than in the previous five years combined, but scientists are still unsure what is afflicting the mammals."

"LITTLE ROCK, Ark. -- Federal pipeline safety officials on Tuesday issued a corrective action order to ExxonMobil Pipeline Co. after one of its pipelines ruptured last week in central Arkansas."

"The so-called 'Monsanto Protection Act,' a controversial provision protecting the biotech giant from litigation, has found an unusual critic in the tea party."

"A coalition of environmental groups wants air-quality officials to determine if the refining of heavy Canadian crude has an effect on local health and safety."

"YAKIMA, Wash. -- Underground tanks that hold a stew of toxic, radioactive waste at the nation's most contaminated nuclear site pose a possible risk of explosion, a nuclear safety board said in advance of confirmation hearings for the next leader of the Energy Department."

"GRANTS PASS, Ore. -- The last partner has dropped out of a proposal to ship coal from Montana and Wyoming to Asia through Oregon's Port of Coos Bay, port officials announced Monday."

"Scientists taking a first look at the genetics of the bird flu strain that recently killed two men in China said Wednesday that the virus could be harder to track than its better-known cousin H5N1 because it might be able to spread silently among poultry without notice."

"WASHINGTON -- The Environmental Protection Agency's latest proposed tightening of limits on sulfur in gasoline, and its previous rules, will most likely have the perverse consequence of retarding the development of cars running on batteries, advanced biofuels or hydrogen -- all promising but expensive technologies that have not become mass-market products."

"DENVER -- Authorities are investigating after construction crews discovered a problem with a liquid gas pipeline that allowed a carcinogen to seep into the ground near a large creek that feeds into the Colorado River."

"Cleanup costs at a single northern mine next to Great Slave Lake are ballooning so high they are forcing Ottawa to rethink plans for thousands of contaminated sites across the country."