Largest crane on the Eastern Seaboard arriving to start removing Baltimore bridge collapse wreckage

BALTIMORE -- Crews working to clear the steel frame of the collapsed Francis Scott Key Bridge and the 984-foot cargo ship that felled it face "an incredibly complex job" - one that is essential to reopening the Port of Baltimore and recovering the remains that may lie under the wreckage, Maryland Gov. Wes Moore said Thursday.

"When you have a chance to see that wreckage up close, you fully understand the enormity of the challenge," Moore said in a news conference, noting, "Our timeline will be long."

The largest crane in the Eastern Seaboard was expected to arrive Thursday evening to help clear the wreckage, Maryland Sen. Chris Van Hollen said, though it wasn't yet on site as of early Friday. Additionally, three heavy lift vessels should begin arriving Friday, Transportation Secretary Pete Buttigieg told CNN.

Maryland officials are working "full speed" to reopen the vital shipping channel and revive traffic through the port - the largest in the US for autos and light trucks, handling a record 850,000 vehicles last year, Moore said. Nonetheless, he said, "We have a very long road ahead of us."

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The cargo ship - nearly the length of the Eiffel Tower - has had as many as 4,000 tons of steel frame weighing on its bow since it struck the Key Bridge early Tuesday, sending a crew of eight construction workers plunging to the waters below, he said.

Only two workers survived and the bodies of two others were later pulled from the water. Authorities believe the submerged tangle of steel and concrete is enveloping the remains of the last four construction workers, and say the debris must be removed before divers can safely search the area.

Recovery efforts will continue to be a top priority, Moore said, adding that it is "our obligation to bring a sense of closure to these families."

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Officials are conducting a full assessment of the debris pieces before they can be lifted from the water, US Coast Guard Rear Adm. Shannon Gilreath said. This appraisal is critical in determining how small to cut the bridge pieces so cranes can lift them, he said.

Over 2,400 feet of boom have also been deployed to contain any potential pollution leaks from the ship, Moore said. National Transportation Safety Board investigators have said 56 containers on the vessel contain hazardous material, mostly corrosives and flammables, as well as some lithium-ion batteries.

Demolition workers may be able to clear a channel large enough for ships to pass through as soon as a month after the required equipment arrives on scene, according to an expert in the field familiar with ongoing discussions.

The expert, who spoke to CNN on condition that his name not be used, said it will likely take longer than that to remove all the debris, but clearing the 1,200-foot area between the two pillars that supported the bridge's main span will be enough to reopen the port to traffic.

The Army Corps will cover the full cost of clearing the channel where the bridge collapsed, Sen. Van Hollen said.

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Federal transportation officials said Thursday they would provide the $60 million requested by Moore as a "down payment" toward clearing and rebuilding the Key Bridge. The funds, requested by state officials earlier Thursday, will go toward removing debris, rerouting traffic and ultimately rebuilding the bridge.

The state can later request additional funding, and Maryland's congressional delegation said they would press fellow lawmakers to fund the rebuilding project.

'This is about the nation's economy'

The economic fallout of the bridge collapse could be wide-ranging as the crisis has indefinitely halted the flow of ships in and out of the Port of Baltimore and delivered a stunning blow to the thousands of dock workers who rely on the busy port.

"This is not just about Maryland, this is about the nation's economy," Moore said Thursday. "The port handles more cars and more farm equipment than any other port in America. And at least 8,000 workers on the docks have jobs that have been directly affected by this collapse."

To aid port workers, the Maryland Department of Labor has established a hotline for unemployment insurance, the governor said.

Ports up and down the East Coast are gearing up to temporarily accommodate cargo shipments that would have otherwise arrived in Baltimore, and several sectors will have to reroute supply chains, including railroad and trucking operations, Buttigieg told CNN Thursday.

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Earlier, the governors of New York and New Jersey said their Port Authority could take on additional cargo to minimize supply chain disruptions.

Managing supply chain disruptions and reopening the port "is not going to be a small project by any stretch," Buttigieg said.

"We know that it's going to be costly, but we also know that that cost is worth it to get Baltimore back on its feet, to get everything back to normal and to support our traffic systems and supply chains," he added.

Investigators interviewing vessel's pilots and crew

As salvage efforts are underway, the National Transportation Safety Board has been gathering evidence at the scene of the crash, interviewing witnesses and analyzing the ship's data recordings.

Two pilots who were tasked with guiding the ship out of port were expected to be interviewed by authorities Thursday. The vessel's captain, his mate, the chief engineer and another engineer have already spoken to investigators, said NTSB chair Jennifer Homendy.

Investigators have used audio and data from the 213-million-pound ship's voyage data recorder to extract clues as to what happened in the moments leading up to the collision.

The first sign of distress came just under three minutes before the crash when the cargo ship's pilot called over the radio requesting any tugboats in the area to respond to the vessel, Homendy said.

Within a minute, police officers on both ends of the bridge were ordered to stop traffic crossing the bridge, said Marcel Muise, the NTSB investigator in charge of the collapse inquiry. Officials have credited this swift action for saving lives.

During their first full day at the scene Wednesday, investigators saw the "utter devastation" of the mangled bridge - pieces of which are still draped over the ship's bow, Homendy said.

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The Dali, a Singaporean-flagged container vessel, had 23 people on board - 21 crew members and two pilots. Of the crew members, 20 are Indian nationals who are "in good shape" following the crash, India's Ministry of External Affairs said Thursday.

Only one member was slightly injured and required some stitches, said spokesperson Randhir Jaiswal.

All crew members were still onboard the cargo ship as of Thursday, said an Indian Ministry of External Affairs senior official familiar with the matter.