Police and Pike River agency rule out putting camera down air pipeline at mine
Monday, 1 March 2021
A risk assessment team has decided it would be too dangerous to put a camera down the compressed air line at the Pike River mine.
The police put cameras down three 300-millimetre pipes in the West Coast mine in January, but were unable to penetrate beyond the roof fall due to the extent of damage to each pipe.
A roof fall sits at the top of the 2.3-kilometre drift (or access tunnel), blocking access to the mine workings. The Pike River Recovery Agency has been tasked with recovering any evidence in the drift to find out what happened when 29 men died after the mine exploded in November 2010.
An electrical engineer who has been investigating the disaster with the support of some Pike River families previously called for the agency to deploy a camera down the mine's compressed air pipeline.
**READ MORE:
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* Pike River re-entry to be finished in six months, agency boss says
* New borehole into Pike River mine could investigate cause of explosion
**
Richard Healey said the 150mm pipeline fed fresh air into the mine, and he had data showing the line was broken just before the first explosion on November 19, 2010. It continued to pump 6 cubic metres per second of air into the mine after it was broken somewhere between 1400 metres and 2400m up the mine.
He said a camera could see if the pipeline had broken at an area called “the goaf” and could examine whether it had collapsed.
The royal commission into the disaster, held in 2011, said mining experts found a substantial volume of methane fuelled the explosion.
“The area most likely to contain a large volume of methane was a void (goaf) formed during mining of the first coal extraction panel in the mine,” it said.
The agency and police, in a joint statement, said the agency carried out a risk assessment on whether to deploy a camera through the air pipe.
“As a result of that assessment the decision has been made not to deploy a camera,” it said.
Police refused to release the footage from the three 300mm pipes, but said it revealed significant damage to the “heavy-walled” pipes.
“The 150mm galvanised pipes are light walled, so it's a fair assumption they would also be significantly damaged. The risk assessment team has assessed the risk as too high.”
It said the 150mm pipes were under tension. One end of the pipes went into the roof fall, and the other end was buried in the Rocsil plug.
The risk assessment said the pipeline could only be accessed by removing a coupling, but doing that would result in the pipe “springing unpredictably”.
The statement also said the risks were too high because the workers would need to use ladders to access the pipes, which were 2m off the floor, and would need to wear breathing apparatus.
“Safety has always been the top priority during this project.”
Healey said he was disappointed in the decision as he believed the risks could be easily managed.
Police were still investigating any criminal culpability for the 2010 disaster with the help of a $50 million Government-funded re-entry of the mine’s drift by the Pike River Recovery Agency.
The agency recovery team last month reached the roof fall 2.3km up the drift and was now completing a forensic examination of an area called Pit Bottom in Stone, which held key electrical equipment.
The mine site was due to be handed over to the Department of Conservation by June for inclusion in the Paparoa National Park.