Two of the four East River tunnels connecting Penn Station to Long Island are undergoing major reconstruction after damage from Superstorm Sandy.
The repairs have been ongoing for six months and raise concerns about LIRR delays.
Deep below the streets of Midtown, a small army of workers toil 24 hours a day, seven days a week.
Their mission is to demolish, repair and rebuild a pair of tunnels damaged by Sandy.
They are lines owned by Amtrak, but also used by legions of Long Island Railroad and New Jersey Transit riders who travel in an out of Penn Station each and every day.
"Inside these bench walls are conduits that were holding the electrical wires and all the systems," said Warren Lebeau with Amtrak. "Those had been crushed over 110 years and there was no extra room to pull in new wires."
On Wednesday, Amtrak showed reporters the progress made in the last six months.
The demo work is complete and the rebuilding of infrastructure and bench walls is in full swing on the currently closed line 2 tunnel.
If all goes well, the work should be wrapped up by July of next year.
The MTA takes credit for some of the progress after pointing out some concerns early in the project.
"Some of the things we saw was responses, stationing personnel to make sure that they are in the right place at the right time to respond," said LIRR President Rob Free. "And make sure certain inspections are being done, equipment. And we worked together and we figured it out."
"We are working together, communicating, talking making sure we understood each other about how we would route trains in and out of Penn Station with only three tubes," Amtrak Laura Mason.
After the rebuild, comes the installation of new signal and electrical systems followed by a critical time of testing inside the two-and-a-half mile tunnel that runs from Penn Station to Long Island City.
At that point, the lengthy project is only halfway complete.
There's a three-month transition period between the end of work on the first tunnel and the start of work on the second tunnel. Once that begins, it's another 13 months of demolishing, repairing and rebuilding.
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