National (U.S.)

"Engineering experts probing the Gulf of Mexico oil spill exposed holes in BP's internal investigation as the company was questioned Sunday for the first time in public about its findings."

For years, mine safety experts urged the Mine Safety and Health Administration to require coal-dust monitors in mines. Mining companies and MSHA resisted. Now Massey Energy Co. is using the lack of such monitors as an argument to deny charges that it did not do enough to control the buildup of explosive coal dust at its Upper Big Branch Mine, where 29 workers died in a massive blast on April 5.

Are fireflies vanishing from the U.S. and Canada because of light pollution? A new study by the Museum of Science Boston aims to use the backyard observations of hundreds of citizens to find out.

A 2008 natural gas explosion that killed a man in Sacramento "was one example of what many experts and studies say is weak oversight of gas pipelines in the United States, a problem that has contributed to hundreds of pipeline episodes that have killed 60 people and injured 230 others in the last five years. Those figures do not include the final toll of the explosion of another Pacific Gas and Electric pipeline this month in San Bruno, Calif., that left seven people dead and more than 50 injured."

"The federal loan guarantee program and other aid for new nuclear plants may not be enough to induce Constellation Energy to build a third reactor at its Calvert Cliffs site, 40 miles south of Washington, the company’s president and chief executive said on Thursday."

"Six Massey Energy management personnel -- including the company's corporate safety director -- have filed suit challenging subpoenas that would force them to answer questions about the April 5 explosion that killed 29 workers at Massey's Upper Big Branch Mine."

"A bill to enact a federal mandate  for renewable electricity is gathering steam in the Senate. And unlike many issues in Washington these days, the measure is gaining support on both sides of the aisle. On Thursday, Chuck Grassley (R-Iowa) became the latest Republican to back a renewable electricity standard (RES)."

"Louisiana Democrat Mary Landrieu today vowed to block the Senate's confirmation of a top White House nominee until the Obama administration takes action on its deepwater drilling moratorium."

"The oil giant nears an agreement to dispense $500 million through an alliance overseen by gulf state governors. Critics fear expertise elsewhere will be overlooked."