NEWARK, N.J. (CBSNewYork/AP) — A new study issued Monday said there is a 25 percent chance that the 106-year-old rail tunnel under the Hudson River will have to close for repairs before a new one is built.

As WCBS 880’s Stephanie Colombini reported, the plans for the new tunnels are taking too long for the group Common Good.

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Study author Philip Howard said if it takes the expected three years to go through the environmental review process, it is likely the existing tunnels will not make it through the construction of the new ones.

U.S. Sen. Charles Schumer (D-N.Y.) called the scenario a “transportation Armageddon.”

“If one tunnel closes down – one of the old tunnels – 65,000 commuters have to find another way into Manhattan,” Howard said.

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Howard said 18 months of red tape is the golden number.

“That 18-month difference not only saves a lot of money, it saves about $3 billion,” he said.

The group is calling on President Barack Obama to issue an executive order expediting the process.

The estimated $20 billion Gateway Project includes new rail tunnels under the Hudson River to replace the century-old tunnels damaged by Superstorm Sandy, and a new connection at Penn Station.

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