That's the word Tuesday from Joseph Lhota, the chairman of the Metropolitan Transportation Authority.
Lhota made the revelation at a meeting of business leaders on Long Island.
The MTA is building a new tunnel under the East River to allow LIRR trains access to Grand Central. Now, all LIRR trains go to Penn Station, on Manhattan's west side.
Lhota says there have been problems tunneling underneath a rail yard in Queens. The MTA has brought in experts from Europe to help with developing a plan going forward.
The project has been delayed several times. Earlier estimates were for it to be completed by 2015.
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