(Portland, OR)  --  The Port of Portland is buzzing with activity again, as Longshore union workers try to catch up on a backlog of shipments.  The containers began to accumulate after a labor dispute began October 31st of last year with waterfront terminal operators and shipping lines.  The dispute affected dozens of West Coast ports as discussions took place between the International Longshore Workers Union and the Pacific Maritime Association.  A tentative agreement was reached Friday, and union workers are scheduled to vote on whether to approve the agreement in the next few weeks.