ENGINEERS AT the World Trade Center site have discovered a 30m long gash in one of the walls of the 'bathtub' structure beneath the collapsed towers.
The massive crescentshaped hole runs along the top of the slurry wall which retains the River Hudson flowing alongside the site.
Since the 11 September terrorist attacks, the walls previously secured by the buildings above have been held in position largely by the debris which fell into the basement up to 21m deep.
Engineers, fearful of inundation by the Hudson if the walls were to fail, whave been gradually excavating the debris and installing ties to secure the wall.
Partner at consultant Mueser Rutledge George Tamaro, who is leading the excavation and stabilisation work, said that pumping around the hole at the south east corner of the site near the junction of Greenwich Street and Liberty Street was ensuring that water did not flood the basement.
'We knew the hole was there and believe it was caused by the top of Tower Two crashing into the basement. However we did not know the extent of the damage, ' said Tamaro.
He said that the work to uncover debris near the hole was proceeding very gently.
The lost section of wall must be rebuilt before the top level of ties can be installed.
Tamaro said that up to 10 bodies a day were still being uncovered in the basement.
He added that it was hoped that the bulk of the bathtub work would be completed by May.