RAILTRACK CHIEF executive Gerald Corbett last week accused Balfour Beatty of failing to react to information from ultrasonic testing of the rail which caused last month's Hatfield crash.
He also said Balfour Beatty had not recommended Railtrack impose speed restrictions on the East Coast Main Line.
Speaking to the all party House of Commons sub-committee Corbett said that Railtrack was reviewing contracts with its maintenance contractors.
Balfour Beatty did an ultrasonic test on the Hatfield line in June using a train mounted machine, but this was inconclusive. It later retested the line but again failed to produce a conclusive result.
Balfour Beatty said there was no problem with the train mounted testing unit, but that the ultrasonic signal could have been affected by 'shelling' on the rail.
A spokesman said shelling was not unusual. It occurs when the upper surface of a rail starts to spall as groups of shallow horizontal cracks form a few millimetres below the surface.
The contractor refused to comment further pending the outcome of the crash investigation.
Corbett confirmed that Railtrack was looking at changing how it dealt with its contractors. He added it may make alterations to the new IMC2000 contracts.