The Pike River tragedy was preventable and caused by the mine being used before it was ready and the company ignoring warnings of explosive methane levels, a royal commission has found.
In a damning report on the November 2010 explosion that killed 29 workers, the commission found Pike River's "drive for coal production before the mine was ready created the circumstances within which the tragedy occurred".
It recommended sweeping changes after finding the Department of Labour failed.
Labour Minister Kate Wilkinson has resigned her portfolio in the wake of the report's release, to take effect immediately.
The commission found there had been reports of excess methane, as well as other health and safety problems, for "months".
In the two days before the explosion there were 21 reports of methane levels reaching explosive volumes and 27 reports of lesser but still potentially dangerous volumes.
"The reports of excess methane continued up to the very morning of the tragedy. The warnings were not heeded."
It also found that Pike River began operating the West Coast coalmine before its health and safety systems were adequate.
Drainage and ventilation systems "could not cope" with everything the company was trying to do, such as driving roadways through coal, drilling ahead into the coal seam and extracting coal by hydro mining.
The company had only one mine that was its revenue source and had to continually borrow to keep operations going.
Pike River's initial estimates that the mine would produce more than a million tonnes of coal a year by 2008 were unrealistic. It had shipped only 42,000 tonnes.
The commission found that the company's board of directors did not ensure health and safety was properly managed and its executive managers did not properly assess the "unacceptable risks" workers were exposed to.
"Mining should have stopped until the risks could be properly managed," it said.
The Department of Labour should have prohibited the mine from operating until adequate systems were in place.
It "assumed" Pike River was complying with the law "even though there was ample evidence to the contrary".
The commission found there was no "predictable window of opportunity" for the Mines Rescue Service to safely enter the mine after the first explosion.
There was no system for sampling the mine's atmosphere after an explosion, so it was "impossible" to assess the risks of entry.
The location of the main underground fan and damage caused to the backup fan on the surface meant the mine could not be reventilated quickly.
The commission found comments by chief executive Peter Whittall after the first explosion, including that fresh air was being pumped into the mine and men were waiting underground for a rescue attempt, gave false hope.
However, the commission found he did not intentionally mislead the families or the public.
Although the comments were "over-optimistic, even unwise", they were made under "extreme stress".
"He allowed his desire for a successful outcome to intrude."
Whittall's announcement to the victims' families of a second explosion five days later "went horribly wrong" when he raised hopes about improved gas levels before Superintendent Gary Knowles told them it was not survivable.
"The scene turned to one of profound distress," the commission said.
KEY'S EARLY INSIGHT
Speaking earlier today, Prime Minister John Key said the report made 16 significant recommendations and the Government planned to adopt the "vast overwhelming bulk" of them.
He would not identify which recommendation the government would not adopt.
The Government has had the report for a week.
"There's been some very good people on the royal commission and it's been extremely thorough in terms of the work that they've done,'' Key said.
"The report is sobering to be perfectly frank and so I think you will see some significant recommendations that the Government will adopt."
RAW DISCUSSION WITH FAMILIES
Cabinet ministers Gerry Brownlee and Chris Finlayson left a briefing with families of 29 Pike River victims saying it was a "raw" discussion.
Brownlee said outside: "There's never an easy meeting, discussing something as raw [as this]. We are still deeply disappointed it happened."
Finlayson said the families were "heartened by what we had to say" in the "particularly difficult" meeting.
He said it would be up to key to discuss the findings and reccomendations at 4pm.
The spokesman for many Pike River families said earlier it was an insult to the 29 dead men that Key was not in Greymouth today.
Families of the men who died in the disaster in November 2010 went into a private meeting to read the royal commission's findings and recommendations after 10 weeks of hearings over nine months.
Bernie Monk, who lost his son Michael in the blast, said Key's non-appearance was "an insult".
"This is a major, major thing that has happened in New Zealand," he said.
The report follows 10 weeks of public hearings over nine months and damning evidence of safety failures at the West Coast coalmine.
Families of the 29 men who died during a series of explosions in the underground mine have called for someone to be held culpable and manslaughter charges laid. Some also want to see the offence of corporate manslaughter introduced.
Key told TVNZ's Breakfast show this morning he had not had any advice on introducing a charge of corporate manslaughter, and there was no recommendation for financial payments to the families.
The bodies of the 29 men remain underground, with families desperate to get them out.
Key said he understood their emotions and desire for closure.
''I've never had an expert in my office yet who has believed that there is a safe and credible plan that's been presented [to recover the bodies].''
It was not a matter of money, although it would cost a lot, but rather the safety of those sent in, he said.
Carole Rose, mother of Pike River victim Stuart Mudge, said with the inquiry complete, the families hoped someone would be held culpable and manslaughter charges laid.
''Twenty-nine men died. We want to see charges ... Somebody is responsible for this,'' she said.
The inquiry heard allegations of workplace bullying, a report showing gas levels spiked to explosive levels six times in five days a month before the mine exploded, evidence from one former mining operator who left the company fearing the mine could explode at any moment, ''impossible'' workloads facing mines inspectors, a lack of enforcement action, plastic bags placed over gas sensors, a lax safety attitude encouraged by production bonuses, potentially flammable gas mixtures in an electrical substation and safety systems inside the mine being bypassed.
Former mine manager Peter Whittall has pleaded not guilty to 12 charges laid under the Health and Safety in Employment Act.
In evidence to the inquiry, the "horrified" chairman of the Pike River Coal board, John Dow, said management, including former chief executive Gordon Ward and Whittall, had kept safety problems from the company's board.
Neville Rockhouse, a former safety manager at Pike River mine whose son, Ben, died in the explosion, was one of those who gave evidence against the company.
He said the families had pushed for the commission to recommend a law change introducing corporate manslaughter to sheet home culpability in future mine accidents.
"It's something they already have in Britain and Australia,'' he said.
"It is something the Government seriously needs to consider, otherwise boards and executive management can make whatever decision they like and hide behind the company. It would draw a line in the sand."
Whatever the commission recommended, he expected the Government to act with urgency to implement any changes.
"They'd be bloody insane if they didn't,'' he said.
''The bomb started ticking a long time ago for this particular mine when the Department of Labour didn't think the mining industry was worth an improved code of practice, when they disbanded the inspectorate and disbanded the mining act and its regulations."
The Pike River tragedy was described during the inquiry as "a homicide investigation of huge proportions", involving more than 200 witnesses being interviewed, with another 170 still to be spoken to.
A police spokesman said yesterday their investigation was continuing and it was not known how long it would take.
The royal commission report comes as the families fly in international mining experts to help them in their bid to convince authorities that it is safe to stage a recovery of the bodies.
After promising the families he would do all he could to bring the bodies home, Key has repeatedly told them the Government's experts think the mine is too unsafe to enter.
The families will be handed copies of the report in Greymouth today, but Key has sent two senior ministers instead of fronting personally.
The report will also be released in Wellington and a spokesman for Key said Key would front a press conference to announce the response immediately after the Cabinet considered the report.
WORST MINING DISASTER IN 96 YEARS
The Pike River coalmine exploded on November 19, 2010, killing 29 men.
For days New Zealand held out hope that they would be pulled out alive from the mine, deep in the Paparoa Range, 40 kilometres north of Greymouth.
Pike River Coal's chief executive at the time, Peter Whittall, told the media that the men could be sitting around an open pipe breathing fresh air while waiting for rescue.
When the mine exploded a second time five days after the first, all hope of rescue was lost.
It was New Zealand's worst mining disaster in 96 years.
Key promised everything would be done to bring the men home.
A royal commission was announced to establish what happened and why, plus how to avoid future tragedies.
Its three appointed commissioners were chairman Justice Graham Panckhurst, a West Coast-born senior High Court judge; Stewart Bell, Queensland's commissioner for mine safety and health; and David Henry, former commissioner of Inland Revenue and the Electoral Commission.
Ten weeks of public hearings spanned nine months, starting in July last year. They were divided into four phases, with 57 witnesses giving oral evidence and more than 200 others filing written submissions. The commissioners had to consider more than 70,000 pages of evidence.
Damning evidence of safety failures was presented and the Pike River mine was labelled an "accident waiting to happen".
The Labour Department, now part of the Business, Innovation and Employment Ministry, and the Government also came in for criticism for its weakened mining inspectorate and under-regulated laws.
- Fairfax Media
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