A worker installs solar panels atop a government building in Lakewood, Colo. The industry has added more than 80,000 jobs since 2010, according to The Solar Foundation.
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Cruden ranks the Gulf oil spill as one of the most significant environmental disasters of our time. It "deserves ... all of our energy to make sure nothing like this ever happens again," he says.
The city of Des Moines, Iowa, sits on the Raccoon and Des Moines rivers. The city's water works says it will sue three neighboring counties for high nitrate levels in these waterways.
An excavator loads a truck with oil sands at the Suncor mine near the town of Fort McMurray in Alberta, Canada in 2009. Environmental groups that oppose oil sands mining have pointed to delayed and canceled projects as a sign of recent success.
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