This video discusses how a vote in Alaska may affect the permitting of the Pebble prospect, which could become the largest mine in North America.

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This video takes a peek inside the daily session in which leaders of the spill cleanup in Venice, La., develop a constantly evolving approach to fighting back the oil spreading along the Gulf Coast.

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In this video, The Times's Jim Yardley tours the Yellow River, witnessing China's rampant pollution, booming urbanization and uncertain future.

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This video discusses how global warming and coastal development are decimating Pacific sea turtle populations. In Costa Rica, a group of one-time poachers is giving baby sea turtles a chance at survival.

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September 27, 2010 -- Thousands of walruses gathered together in a dangerous "haul out" on the coast of Alaska earlier this month. Scientists say the walruses came ashore in such large numbers because their normal habitats, Arctic ice floes, are melting.

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