A gantry that malfunctioned last Friday, sending a 90-tonne slab of concrete into the Fraser River, will be out of commission for at least a week.A spokesperson for the Port Mann Highway 1 project said the gantry used to hoist pre-fabricated concrete deck sections into place has to be leveled and repaired before it will be back in service, which could take up to two weeks.In the meantime, workers have been deployed to other sections of the bridge."Once the leveling and the plan for repairs has been completed we'll have a better idea of the next steps and the time frame involved," Logan said.It will be up to contractors Kiewit-Flatiron to make-up for any delays and costs caused by the malfunction.No workers were hurt in the accident last Friday morning during construction of the new Port Mann Bridge. But the incident put an immediate halt to the construction of the approaches to the the new bridge.Logan said the contractor Kiewit-Flatiron is investigating the cause of the malfunction and will remove the concrete deck section from the river if it can."It's not desirable to leave it in the river, although it's not affecting navigation or river use," Logan said.Once the concrete slab has been hauled out of the river, the contractor will decide if it can still be used or if a new one will have to be cast at a plant in Coquitlam's Pacific Reach industrial park.The concrete section that fell into the river is one of 1,100 needed for the Coquitlam and Surrey bridge approaches. So far about 1,000 have been hoisted into place, Logan said.The main span, meanwhile, is built of steel girders topped with concrete deck panels.WorkSafe BC is also investigating the accident although no one was hurt.Logan said the yellow horizontal construction gantry had tipped to the south and was immediately secured. It has been tied down so it won't move he said. An assessment confirmed the damage is limited to the base or footing and not to the yellow gantry or the bridge deck. Work is expected to begin this week to restore it to its proper level position so repairs can be done.Coquitlam is the staging ground for much of the $3.3 billion bridge and highway construction project. The toll bridge is expected to be open in 2013.dstrandberg@tricitynews.com