Seattle garbage collector Anousone Sadettanh empties a small residential garbage bin into his truck in 2014. It is now illegal to toss out food with the trash in the city. Residents will get warning tags for now; the city will start imposing fines in July. Elaine Thompson/AP hide caption

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A polar bear walks in the Arctic National Wildlife Refuge.The Obama administration is proposing new protections in the region that would ban mining and drilling. Subhankar Banerjee/AP hide caption

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The Los Angeles River in 2013. Engineers turned it into a narrow concrete channel in the 1940s, after a flood destroyed homes and left 100 people dead in 1938. Steve Lyon/Flickr hide caption

itoggle caption Steve Lyon/Flickr

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. John Moore/Getty Images hide caption

itoggle caption John Moore/Getty Images

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. Gerald Herbert/AP hide caption

itoggle caption Gerald Herbert/AP

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. iStockphoto hide caption

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