TRENTON — Despite his repeated claims the Hudson River train tunnel was projected to run $2.3 billion to $5.3 billion over budget, Gov. Chris Christie has known for two weeks that the official federal estimate showed a cost overrun of as low as $1 billion, two people close to the project said.

The revelation came hours before the governor was scheduled to speak Friday with U.S. Transportation Secretary Ray LaHood, who will try to persuade Christie — again — to save the tunnel that was designed to double rail capacity between New Jersey and midtown Manhattan.

Among the added incentives LaHood may offer to keep the nation’s largest public works project alive are federal high-speed rail grants and cost-sharing with Amtrak to expand rail capacity, said those close to the project. They asked not to be named because they are not at liberty to discuss the talks publicly.

Christie announced Oct. 7 that he was killing the project, originally slated to cost $8.7 billion, because of projections by an advisory committee that pegged the cost at $11 billion to $14 billion.

But after meeting at the Statehouse with LaHood the next day, Christie agreed to delay his final decision for two weeks until the secretary and other officials presented him with cost alternatives. It is not certain whether the governor will make a formal decision Friday.

Those close to the project said it was during the meeting two weeks ago that LaHood told the governor the low estimate for the project was $9.7 billion.

Part of the reason for the differing numbers is that Christie’s figures include $800 million to build two tracks along a new bridge over the Hackensack River just south of the existing Portal Bridge between Kearny and Secaucus. The 100-year-old bridge is in disrepair and is so low it is often opened to allow commercial boats underneath, leading to delays.

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Federal officials have counted the tunnel and Portal Bridge projects as separate entities, while Christie has maintained they are joined at the hip and should be counted in the same cost estimate.

Including the Portal Bridge, the estimate LaHood gave Christie was $10.6 billion to $13.5 billion, said a third person familiar with the talks.

The governor has continued to use the higher cost projections in his public criticism of the project.

"You may have read about this $8.7 billion tunnel that’s being planned up in New Jersey to go into New York," he told a crowd in Allentown, Pa., on Wednesday. "And listen, it’s not a bad idea. But it’s now running $2 billion to $5 billion over its original estimate."

Although federal transportation officials have seethed over Christie’s use of the higher projections even after his meeting with LaHood, they had kept the $9.7 billion figure a closely guarded secret because of the transportation secretary’s belief he could conciliate with Christie.

The 9-mile tunnel from Secaucus to West 34th Street in Manhattan, formally known as Access to the Region’s Core, or ARC, was expected to be completed by the end of 2018.

NJ Transit Executive Director Jim Weinstein, a member of Christie’s tunnel advisory committee, said projections, by their very nature, are not an exact science.

"The reality is, you don’t know the real answer for this stuff until it’s all built and operated — and that’s eight, nine years from now," he said. "You’re trying to project the future."

Weinstein said Christie does not want New Jersey taxpayers to be on the hook for cost overruns.

"The governor’s concern — and it’s a valid concern — is sort of signing a blank check that New Jersey is going to have pay for," he said. "And he is not going to do that."

The federal government and the Port Authority of New York and New Jersey have pledged $3 billion each for the project, with New Jersey picking up the remaining $2.7 billion, plus overruns.

As the latest tunnel episode unfolded, the chairman of the Assembly Transportation Committee said his request for records related to Christie’s decision to cancel the tunnel failed to justify the governor’s claim of up to $5.3 billion on cost overruns.

"That claim seems as though it was simply pulled out of thin air by the governor," Assemblyman John Wisniewski (D-Middlesex) said. "The governor is risking New Jersey’s economic future with numbers that, at least according to these documents, have no basis in reality."

Among the hundreds of pages of documents Wisniewski received through his open records request was a monthly report, amended Oct. 5 — two days before Christie’s announcement that he was cancelling the project — that noted: "The overall project remains within budget."

Christie spokesman Michael Drewniak said what Wisniewski received was the first response to his open records request.

"Given the wide scope and extent of his request, the assemblyman was notified that additional documentation will continue to be provided on a rolling basis," Drewniak said.

By Mike Frassinelli and Josh Margolin/The Star-Ledger

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