"The National Science Foundation has closed its investigation into Pennsylvania State University climatologist Michael Mann after finding no evidence of scientific misconduct related to his research.

It is the latest in a string of investigations to exonerate scientists involved in the so-called "Climategate" email scandal.

"EPA has dropped plans to regulate pollution washing off construction sites for the second time in as many years. The agency slipped the proposed regulation off the table last Friday, eight months after it sent the draft rule to the White House Office of Management and Budget for review."

"Presidential candidate Jon Huntsman is pounding away at rival Rick Perry's skepticism of manmade global warming and criticism of the nation's central banker, saying those stands hurt the GOP and make the Texas governor come off as a not-so-serious national figure."

"Dozens were arrested at the White House Saturday as protesters began a two-week sit-in expected to draw over 2,000 opponents of a proposed pipeline from Canada to the US Gulf Coast."

Groundwater pollution from hexavalent chromium from Pacific Gas & Electric led to the "a $333-million-dollar, class-action settlement in 1996 -- one of the largest of all time -- and inspired the 2000 blockbuster movie bearing [Erin] Brockovich's name." Despite the settlement, PG&E has "done little to contain the plume of hexavalent chromium, which U.S. EPA deemed a likely carcinogen in a draft assessment last year."

"At long last, mainstream media begins to pay attention to the flat denial of basic climate science being pushed by right-wing Republican presidential candidates."

"DENVER—Hispanic leaders in the West have formed a new group called Nuestro Rio to focus attention on the Colorado River, which has sustained generations of Latinos."

"The 12-member congressional supercommittee picked to trim $1.5 trillion from the federal budget will undoubtedly be listening to hundreds of viewpoints on where to cut back. But many of the voices chiming in could be the members' current or former staffers who have close ties to the lobbying world.

More than 100 former staffers of the bipartisan, bicameral supercommittee members have gone to work for entities that lobby Congress, according to data collected by the Center for Responsive Politics.

"The Environmental Protection Agency is emerging as a favorite target of the Republican presidential candidates, who portray it as the very symbol of a heavy-handed regulatory agenda imposed by the Obama administration that they say is strangling the economy."

"CHARLESTON, W.Va. -- Appalachian residents support strengthening Clean Water Act restrictions on mountaintop removal and would punish at the ballot box public officials who work to weaken strip-mining regulations, according to a new poll released Tuesday."