A CRANE driver had a miraculous escape when he leapt from his 100-tonne machine seconds before it toppled over on the edge of a steep ravine yesterday.

Environment Agency officials were called in after fears that diesel from the crane could leak into a beck and threaten a colony of bats.

The Health and Safety Executive is investigating the accident, which took place during construction at Twizell Burn, in Pelton Fell, near Chester-le-Street, County Durham, at noon yesterday.

A Durham County Council spokesman said last night: "We are engaged in strengthening and extending a culvert which carries Twizell Burn underground.

"The ground in the vicinity is hilly and very steep, and the scheme is to enable us to stabilise the sloping ground.

"The crane, on hire by the council's contract services, was lifting materials to the bottom of the slope, where the work is being carried out.

"We understand it was lifting three tonnes of material at the time, which was apparently well within its lifting capability at the configuration it was in."

The spokesman said the jib was extended 50-metres when the crane tipped over and came to a rest upside down with its jib on the bottom of the slope, preventing it from toppling further.

Environment Agency spokesman Louise Turner said two officers were sent to the scene following concerns about the potential leakage of 700 litres of diesel in three tanks.

She said: "Because of the precarious position of the tank, it is not safe enough to make a proper assessment, but there is no smell or sign of any diesel spillage.

"The main concern is that the tanks could be ruptured during the removal of the crane."

Officials with anti-pollution equipment will monitor the rescue operations, which are expected to take place today or tomorrow.

A 500-tonne crane will be needed to remove the vehicle.

The Health and Safety Executive said the crane driver had felt the crane move and managed to get out with seconds to spare.