Other major ports affected would include Savannah, Ga., which handled 18 million tons, and Houston and Hampton Roads, Va., which each handled more than 12.5 million tons.
Thousands of other jobs would be directly affected by the shutdown. Truck drivers might not have any cargo to transport, tug boat captains no ships to guide and freight train operators nothing to haul.
Simultaneously, another labor dispute involving dock workers was playing out on the West Coast.
Longshoremen at several Pacific Northwest grain terminals worked Thursday under contract terms they soundly rejected last weekend. The owners implemented the terms after declaring talks at an impasse. The International Longshore and Warehouse Union has yet to announce its next move.
Workplace rules, not salary and benefits, have been the obstacle to a new deal.
The dispute involves terminals in Portland, Ore., Vancouver, Wash., and Seattle, where longshoremen have been working without an agreement since the last contract expired Sept. 30.
Associated Press writers Ken Thomas in Washington and Tamara Lush in Tampa, Fla., contributed to this report.
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