Case against Pike River Coal outlined

Flames leap from the ventilation shaft at the Pike River Mine in November 2010. Photo / Mark Mitchell

Any survivors of the first explosion that tore through the Pike River underground coalmine, killing 29 workers on November 19, 2010, would have been stumbling around in the dark, a hearing in the Greymouth District Court has been told.

Judge Jane Farish is hearing, by formal proof, evidence that the Ministry of Business Innovation and Employment (formerly the Labour Department) has compiled against the Pike River Coal Company.

The ministry has laid nine charges against the company, alleging that it could have taken numerous practicable steps to avoid the explosion, the most significant being that it should have placed the main ventilation fan outside the mine.

Ministry health and safety officer Jane Birdsall said Pike River had failed on many fronts but in particular the lack of proper ventilation and methane gas control. She also noted that the rescue chamber and smoke lines, or lifelines, were inadequate.

The smoke lines that hang from the ceiling are supposed to guide workers, in blackout conditions, to the rescue chamber. Inside Pike mine they were non-existent in some places and damaged in others, tangled with other fittings or lying on the floor.

These faults had been brought to management's attention but not rectified. Pike River had also ignored its own safety recommendations regarding the main fan.

Ms Birdsall said the decision to place the fan underground was "rare, if not unique to Pike".

However, as risk assessment controls the company was meant to place the fan in an area of stone so there was no possibility of it sparking a coal gas explosion. In addition, "explosion paths" were to be created around it to divert pressure from the fan and enable it to continue to operate at times of emergency.

Instead, the fan was sited further into the mine in the coal seam and the explosion paths had not been created, leaving it unprotected in the path of the main explosion.

The only escape route available for the miners, up the ventilation shaft, involved an initial 55m vertical climb which most, if not all, would have been incapable of at the best of times.

The only underground fresh air base, 1km away from the furthest workings, relied only on a piece of brattice to protect it from gases.

Some underground machinery that should have been fitted with gas detectors was not, the mine did not have a proper methane drainage method, and recommendations that this be rectified had also been ignored, Ms Birdsall said.

At the end of the evidence, Judge Farish reserved her decision to April 18.

Last August, Judge Farish presided over the prosecution of Pike River contractor VLI, a subsidiary of Sydney-based Valley Longwall International, which had admitted three charges; each carrying a maximum fine of $250,000. Those charges related to its failure to take all practicable steps to protect its employees Josh Ufer, 25, Ben Rockhouse, 21, and Joseph Dunbar, 17.

At the time she was criticised for fining the company just $46,000. The judge entered convictions on two counts and imposed the $46,000 fine on the other after the Crown indicated it was not expecting a financial penalty on all three.

The decision drew sharp criticism from the miners' union and the victims' families, who considered the fine lenient.