A Royal Commission's damning report on the Pike River mine tragedy says the company paid insufficient attention to health and safety matters and exposed workers to unacceptable risks in its drive to produce coal.
The commission also heavily criticises the former Department of Labour for failing to properly supervise the West Coast mine in which 29 men died in a series of explosions that began on 19 November 2010. Only two workers, Daniel Rockhouse and Russell Smith, survived the blast.
In its report released on Monday afternoon, the Royal Commission outlined a litany of problems, with many warnings of a potential catastrophe that were not recognised in the months before the deadly methane explosions.
The commission blamed a culture of production before safety at the mine for causing the men's deaths and found that urgent legislative, structural and attitude changes are needed to avoid a repeat of the disaster.
The Department of Labour has come in for particularly heavy criticism for failing to properly supervise operations at Pike River, where the drive for coal production before the mine was ready created the circumstances of the tragedy.
The commission has made 16 recommendations, including that the Government set up a new Crown agency to focus solely on health and safety, and tougher regulations to govern underground mining.
It says workers should also be given greater powers to allow unions to appoint check inspectors with the power to close a mine if it is unsafe, and company directors should be made more responsible for health and safety matters.
The Royal Commission report said the mine was new and owner Pike River Coal Ltd had not completed the systems and infrastructure necessary to safely produce coal, and that health and safety systems were inadequate.
The ventilation and methane drainage systems could not cope with what the company was trying to do, including driving roadways through coal, drilling ahead into the coal seam and extracting coal by hydro mining - a method known to produce large quantities of methane.
The report said there were numerous warnings of a potential catastrophe at the mine. For months, underground deputies and workers had reported incidents of excess methane, as well as other health and safety problems. In the last 48 days before the first explosion, there were 21 reports of methane levels reaching explosive volumes.
Former Pike River Coal chief executive Peter Whittall is defending health and safety charges laid by the Labour Department. The company is also facing charges.
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PM apologises, minister resigns
Prime Minister John Key on Monday apologised to the families of the miners who died, saying on behalf of the Government he deeply regrets what has happened.
"While much of the fault for the tragedy lies with the Pike River Coal Limited, the Royal Commission also makes it clear that the regulatory environment was not effective over a long period of time.
"On behalf of the Government, I apologise to the families, friends and loved-ones of the deceased men for the role this lack of regulatory effectiveness played in the tragedy."
Mr Key said the Government would broadly accept and implement the recommendations, but a small number require further investigation before they could be put in place. It accepts there were systemic failures in the regulatory regime across successive governments.
Labour Party leader David Shearer said the commission's report is thorough and called on the Government to adopt all the recommendations and to extend the health and safety improvements to all workplaces.
Meanwhile, Kate Wilkinson has resigned as the Minister of Labour following the report's release.
Ms Wilkinson said the mining tragedy happened on her watch and she feels it is the right and honourable thing to do. She will retain her other portfolios and remains in the Cabinet.
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Families receive report
Government ministers Gerry Brownlee and Chris Finlayson delivered the Royal Commission's report to families of the victims in Greymouth on Monday before it was made public at 4pm.
Speaking to media after the meeting, Mr Brownlee said it was a tragedy that still affects the families and will do for many years to come, and the Government remained deeply disappointed that it happened.
Mr Finlayson, the Attorney-General, will oversee the implementations of the Government's recommendations and its response to them. He said it was a particularly difficult meeting for the families, but they seemed heartened by what they heard and continued to show courage and forebearance.
Bernie Monk, a spokesperson for some of the victims' families and who lost a son in the mine, described the report as hard-hitting and said it would be beneficial for the families to move on.
Mr Monk said the Government appears to now be taking the families seriously and it is clear from the report that many blunders were made and it wants to make amends for that. The magnitude of what has come out in the report has helped him find closure.
The families have brought in experts, including a group from the Britain, to review a recovery plan. However, Prime Minister John Key has repeated his stance that he had not yet seen evidence that the mine could be safely re-entered to retrieve the bodies.
Failure on every level - lawyer
The lawyer for the Pike River families group said the report paints "an unrelenting picture of failure on virtually every level".
Nicholas Davidson, QC, said the report makes it clear that New Zealand has Third World mining practices and virtually nothing in it is a surprise - except for the emphatic nature of its conclusions.
Mr Davidson said the failures include the way the legislation was applied and the failure of the Labour Department in its inspectorate role. He said government ministers Gerry Brownlee and Chris Finlayson indicated that an offence of corporate manslaughter would be considered.
However, a lawyer representing a group of Pike River Coal's former directors and managers said her clients contest the commission's finding that the West Coast mine had a culture of production before safety.
Stacey Shortall's clients include former chief executive Peter Whittall and former chairman of the board John Dow.
Ms Shortall told Radio New Zealand's Checkpoint programme on Monday that Mr Dow and Mr Whittall contested allegations about the culture at the mine at the hearings and during their employment at Pike River Coal believed that health and safety matters were being appropriately addressed.
Listen to Checkpoint interview with Nicholas Davidson
Listen to Checkpoint interview with Stacy Shortall