Environment

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**FILE** Steam rises from the stacks of Basin Electric's Laramie River Station coal-fired power plant near Wheatland, Wyo., on Feb. 11, 2014. (Associated Press/The Casper Star-Tribune, Alan Rogers)

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FILE - This Oct. 5, 2011 file satellite photo provided by NASA shows algae blooms on Lake Erie. A U.S.-Canadian agency is calling for sharp cutbacks in phosphorus runoff into Lake Erie to counter a worsening problem of algae blooms that degrade water quality, harm fish and chase away tourists. In a report Thursday, Feb 27, 2014, the International Joint Commission identifies farm fertilizer as a primary culprit in feeding runaway algae blooms. It recommends placing Lake Erie on a federal impaired waters list, which would activate a plan to limit phosphorus levels. (AP Photo/NASA, File)

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Jose Ortega, left and Fidel Meza work the soil looking for drip lines in a dry tomato field as storms arrive in the area Wednesday, Feb. 26, 2014 in Lemoore, Calif. The first significant California storm in months barreled down from the north Wednesday, promising much-needed rain to the drought-stricken state but also the threat of mudslides and flooding. A potentially stronger storm is expected to move in late Thursday. (AP Photo/Gary Kazanjian)

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AP10ThingsToSee - Farmer Carlton Duty Jr. checks water content in his dry tomato field as storms arrive in the drought-striken area Wednesday, Feb. 26, 2014 in Lemoore, Calif. Duty said "this year will be a challenge. I'm always glad to have rain, but I'm not sure it's enough." (AP Photo/Gary Kazanjian, File)

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Farmer Carlton Duty Jr. checks water content in his dry tomato field as storms arrive in the area Wednesday, Feb. 26, 2014 in Lemoore, Calif. Duty said "this year will be a challenge. I'm always glad to have rain, but I'm not sure it's enough." The first significant California storm in months barreled down from the north Wednesday, promising much-needed rain to the drought-stricken state but also the threat of mudslides and flooding. A potentially stronger storm is expected to move in late Thursday. (AP Photo/Gary Kazanjian)

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This undated image provided by the U.S. Geological Survey shows researchers measuring a grizzly bear in the Taylor Fork area of the Gallatin National Forest north of Yellowstone National Park in southwest Montana. A government-sponsored research team said Wednesday Feb. 26, 2014, there are no signs of decline among Yellowstone’s grizzly bears despite warnings from outside scientists as officials consider lifting the animals’ federal protections. (AP Photo/U.S. Geological Survey)

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In this photo taken on Jan. 23, 2014, trumpeter swans fly above the Green River at the Seedskadee National Wildlife Refuge outside Green River, Wyo. Trumpeter swans were reintroduced to Seedskadee in the early 1990s and now winter at the refuge. (AP Photo/Casper Star-Tribune, Ryan Dorgan)

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In this photo taken on Jan. 23, 2014, trumpeter swans float on the Green River at the Seedskadee National Wildlife Refuge outside Green River, Wyo. Trumpeter swans were reintroduced to Seedskadee in the early 1990s and now winter at the refuge. (AP Photo/Casper Star-Tribune, Ryan Dorgan)