Old tunnel blamed for mine disaster: Union calls for inquiry into second roof collapse. Steve Boggan reports

THE CONTROVERSIAL roof bolting system criticised in the wake of the Bilsthorpe colliery disaster was probably not to blame for the tunnel collapse which killed three men, according to the first underground inspections.

Brian Langdon, the man leading the inquiry into the disaster, indicated yesterday that old mineworkings had been the main cause of the roof fall, although he stopped short of clearing the bolting system of blame.

These early findings were accepted by Nacods, the pit deputies' union, and the Union of Democratic Mineworkers. But Mick Stevens, general secretary of the UDM, said miners were still concerned about roof bolting and that he planned to call for a full inquiry into another roof collapse in Nottinghamshire, at Wellbeck colliery on 13 August. Before venturing underground at Bilsthorpe to examine the scene and interview witnesses, Mr Langdon, the deputy Chief Inspector of Mines, said: 'The presence of the old roadway and, in particular, the old face line that was adjacent to the old roadway . . . was a major contributory factor.'

Asked whether roof bolting was to blame, he replied: 'The rock displacement was so great that the collapse probably would have occurred whatever system was in place.'

The collapsed tunnel was only one metre away from old workings, according to union officials. The usual distance between new and old workings is about 10 metres.

Mr Langdon's initial observations were based on examinations over the weekend by Health and Safety Executive inspectors and officials from the UDM. But Health and Safety officers were quick to reject early reports which said roof bolting had been cleared of blame. 'Nothing has been ruled in or out yet,' one officer said.

The roof bolting system, in which 2.4m bolts are drilled into the roofs of tunnels, is meant to bind loose strata together to create a solid and safe slab of rock overhead. Mining engineers say it is quick, cheap and problem- free, but critics argue that it is not efficient in British mines, which in many cases have been worked before.

In the incident at Wellbeck, a salvage team was removing chocks supporting an old face, and roof bolts were being used. British Coal said the roof collapse was 'minor' and no one was injured. But Mr Stevens said: 'I don't call any incident like this minor. I want a full inquiry into what happened.'

A government move to enact sweeping deregulation of the mining industry during the parliamentary recess provoked furious criticism yesterday and the prospect of a court challenge from Nacods, writes Patricia Wynn Davies.

Frank Dobson, Labour's employment spokesman, accused ministers of deliberately delaying publishing 'the most far-reaching changes in mine safety in modern times' until after MPs had risen for the summer holiday, and of weakening the existing regulations to induce foreign investors to buy privatised pits.

John Monks, the TUC general secretary, yesterday promised Nacods financial backing in the event of a judicial review of the new rules.

The Management of Safety and Health at Mines Regulations 1993 are due to come into effect on 1 October without a debate.