Yes it did mean to use atomic devices to create a harbour (US spelling harbor) See http://en.wikipedia.org/wiki/Peaceful_nuclear_explosions and this is the item One of the first U.S. proposals for peaceful nuclear explosions that came close to being carried out was Project Chariot, which would have used several hydrogen bombs to create an artificial harbor at Cape Thompson, Alaska. It was never carried out due to concerns for the native populations and the fact that there was little potential use for the harbor to justify its risk and expense.

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