The company was remanded to October 26, 2012 for sentencing at the Greymouth District Court and could be fined up to a total of $NZ750,000.

The charges brought against VLI Drilling by the Department of Labour of NZ do not relate specifically to the Pike River mine disaster, the company said in a statement.

“The charges relate instead to our failure to have a procedure in place to verify that Pike River Coal had conducted its inspections of our drill rig [an LMC75], so that – if these had not been conducted – our rig was not operated,” it said.

DoL’s summary of charges states: “It is not known if the drill rig was operating at the time of the explosion, nor if the power supply to the drill rig was in place.”

VLI Drilling supplied specialist drilling services to PRC at the Pike River mine. PRC was to conduct regular inspections of VLI Drilling drill rig as part of its mine safety management responsibilities.

“This is the standard arrangement with mines in which we provide specialist drilling services, including in Queensland,” VLI said.

“In hindsight, our reliance on PRC’s processes alone is regretted. Our admission to the charges is intended to acknowledge that we could have done more to monitor PRC’s inspections of our equipment.

“Our thoughts remain with the families and friends of all the victims of the Pike River mine disaster.”

Meanwhile the 12 charges against former Pike River coal chief executive Peter Whittall have been adjourned at the request of his lawyers until October 25, 2012 because his legal representatives still require time to consider the evidence provided under disclosure to him.

The Judge noted he expected Whittall to plead on this date.

Pike River Coal Limited (in receivership) has been remanded until October 26, 2012 for formal proof by the Ministry of nine charges. The receivers have indicated they will be taking no further part in the legal process.