The Coast Guard evacuated the Kulluk's 18-man crew Dec. 29, and it drifted for 10 hours the following day after the tug that was towing it lost power.

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It found that the routine the tug crew followed before towing or entering fog was "ineffective", with the watertight engine room door left open and the crew not being used in the most effective manner once in the fog.

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There were also no defined procedures for the tug operators when assisting or towing in restricted visibility, it said.

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