Like most trips of this nature, once the supplies are loaded, the crew of the station will then load the ship with trash and send it back to Kazakhstan.

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Officials and environmentalists have expressed concern that the ship's fuel, at full load at the start of the cruise, could spill into the sea.

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You just can't load them all in one airplane or one big ship and get him into theater.

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Worries are growing that the ship could cause an environmental disaster if it breaks up and sheds its load of about 2, 300 tonnes of fuel.

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During that time, astronauts will load about 2, 300 pounds of cargo back on the ship, and then it will return to Earth on March 25, splashing down off the coast of Baja California.

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