US RAIL operator Amtrak has asked the US Congress for £2bn to fund network improvements for the anticipated surge in rail travel after the World Trade Center attacks.
It wants the money for tunnel upgrades, new rolling stock and security improvements.
A large portion of any grant is likely to be required for work to tunnels serving Penn Station to New York. A US government report last year said £600M would be needed for fire safety improvements alone.
'The tunnels are old and some were built before the American Civil War.
Major work is needed to improve ventilation and escape routes, ' an Amtrak spokeswoman told NCE.
She said the expected growth in traffic and perceived increase in risk after the WTC attack had accelerated ongoing discussions about improvements.
Around 25km of tunnels dating from the 19th and early 20th centuries serve the station running under the Hudson and East Rivers.
Meanwhile engineers working on the 'bathtub' foundations under the collapsed WTC buildings said that it could be four months before debris is removed allowing access for work on the diaphragm wall which retains water from the River Hudson near the site. Originally restrained at the top by the buildings, the wall is now supported by rubble which recovery teams have to remove.
Failure of the wall could lead to catastrophic inundation of rail and subway tunnels.
Concrete plugs were installed last week at the ends of the 500m subway tunnel sections crushed by falling debris.
Geotechnical consultant Mueser Rutledge partner George Tamaro said that this was precautionary rather than due to any increased danger.
'We decided it was prudent. I might have taken risks in the past - but not now, ' he said.
Backfilling around areas where the wall was believed to be weakest has been carried out, he added.
New 'tieback' ground anchors have been installed, along with movement monitoring equipment.
Mueser Rutledge associate Daniel Hahn said that access was proving extremely difficult but that the structure appeared stable.
'If there were new problems with the structure then water flows would increase, and so far they have not, ' he said.