Commission's Report - Volume 1
The regulators
The Coal Mines Act 1979
This was the main act governing coal mining activities until 1992. A specialist coal mines inspectorate administered mining. The inspectorate reviewed applications for exploration and mining licences and inspected the mine once it was developed. This meant that the inspectorate had a hand in the safety of a mine from its planning to closure.
By 1992 a new legislative framework was in place. The granting of exploration and mining permits, the assessment of environmental effects and the regulation of health and safety in coal mining were administered by separate entities under separate acts. The mines inspectorate no longer had a role throughout the life of a mine.
Ministry of Economic Development (MED)
MED approved the issue of Pike’s mining permit in 1997. Its focus was the economic benefits to New Zealand. MED did not fully apply the criteria set out in its coal policy programme, which included requirements to check the experience of the applicant and its proposed mining methods, and to ensure that these represented good mining practice. In terms of the coal programme, health and safety, which is intrinsic to good mining practice, was not MED’s concern. MED did not consult DOL so no one looked at the health and safety implications of the proposed mine.
MED’s subsequent monitoring of the mine development was limited to ensuring that work statements were filed and storing mining plans.
Until 1 January 2009 MED carried out electrical safety inspections for DOL. After that date MED ceased to conduct inspections and DOL had no capacity to continue them.
Department of Conservation (DOC)
In 1998 Pike applied for access to the conservation land where the mine was to be developed. Over the next six years the potential environmental effects of the development were assessed in detail. DOC was concerned to minimise disturbance from surface activities and ensure that underground mining caused only minimal subsidence. In late 2004 an access arrangement was signed. It set out detailed controls.
DOC discharged its statutory function to protect the conservation value of the land. During development of the mine it met the company regularly to manage operational issues and accommodate a number of variations to the access arrangement.
Pike gave no evidence to indicate that DOC’s controls compromised its ability to develop a productive and safe mine. The explosion, when the mine was still in start-up mode, limited the commission’s assessment of whether underground coal mining and conservation and environmental values would have been compatible at Pike River over the longer term.
Local and regional authorities
Pike required resource consents from the Grey and Buller District Councils and the West Coast Regional Council. These were initially granted in 1999, but a number of appeals were not resolved until 2004. The councils considered environmental and public safety issues in terms of the Resource Management Act 1991. Health and safety in the workplace was not part of their mandate.
Department of Labour (DOL)
DOL’s function was to ensure that Pike River was a legally compliant coal mine. The first workplace inspection was conducted in early 2007 when the drift was under construction and the mine design was already settled. From then, mining inspectors conducted quarterly inspections.
DOL’s policy was to tailor a regulatory approach appropriate for individual employers. Because Pike was assumed to be a ‘best practice’ and ‘compliant’ employer the inspectors adopted a low-level compliance approach. This proved ineffective, as was most evident regarding the need to provide two emergency exits from the mine. In mid-2009 the main ventilation shaft was designated the second means of egress out of the mine. To use it involved a 110m ladder climb that was physically exhausting in normal conditions, but probably impossible in an emergency.
In April 2010 an inspector told the mine manager that the shaft, although technically compliant, was not a suitable emergency escapeway. In August DOL advised Pike by letter that a new egress was required ‘as soon as possible’.[8] In November 2010 Pike said a new egress would be established by mid-2011. DOL considered this unsatisfactory, but took no further action before the explosion.
Pike was not a best practice or compliant employer in relation to this and some other obligations. The workforce had voiced concern to management about the unsuitability of the second egress. The start of hydro mining in September 2010 increased the level of risk in the mine to the point where DOL should have issued a notice prohibiting hydro mining until a suitable second egress was in place.
DOL’s compliance strategy did not require an assessment of Pike’s safety and operational information. The inspectors did not have a system, training or time to do so. When, at the hearings, they were shown examples of safety information obtained by the commission from Pike’s records, the inspectors were visibly dismayed. This was not a case of individual fault, but of departmental failure to resource, manage and adequately support a diminished mining inspectorate.
The cause of the explosions
Activities in the mine
Sixteen Pike workers and 13 contractors perished in the mine. Their locations at 3:45pm on 19 November 2010 are not known with any certainty. Eight men, mainly contractors, were probably in the pit bottom area. The other 21 men were most likely at various workplaces, including the hydro panel and four work areas inbye of the panel.
The contractors, other than an in-seam drilling crew, were due to finish work at 4:00pm and could have been preparing to leave the mine when the explosion occurred.
Source of the methane
The expert panel concluded that the size and duration of the explosion indicated it was fuelled by a large volume of methane, perhaps up to 2000m3. Methane accumulated in the hydro goaf following mining was estimated at up to 5000m3. Another roof fall like that which occurred on 30 October 2010 would have caused a large pressure wave bearing a substantial volume of methane.
The pressure wave would have flowed down the hydro panel roadways and entered the main mine roadways, with the potential to flow inbye, particularly if a temporary stopping failed and allowed the wave to enter the main intake roadway. Methane carried along the roadways by the pressure wave would be diluted by air into the explosive range.
Another potential source of methane was an accumulation in the elevated inbye western areas of the mine. High methane readings were reported in these areas right up to the morning of 19 November.
Potential ignition sources
There are a number of possible ignition sources, since a spark is sufficient to ignite methane diluted to within the explosive range.
About midday on 19 November the water supply to the mine was stopped for a maintenance shutdown and mining and roadway development underground had to cease. Late afternoon, the maintenance work was completed and the control room operator reactivated a main pump at pit bottom in stone to restore water to the mine. He then called underground to advise the miners and as he spoke to an engineer all reporting to the control room from underground was lost. The coincidence of the switching on of the pump and the explosion seconds later suggested that an electrical cause may have been the ignition source.
An electrical expert thought that the VSD used to power the water pump could have produced electrical wave form distortion, called harmonics, and caused sparking in the mine earthing system or in a metal pipeline. This theory, however, is disputed and unless experts can re-enter the mine and examine the electrical systems the timing coincidence will remain a matter of conjecture.
Another potential ignition source is contraband. Smoking materials and battery-powered devices, including wristwatches and cameras, are prohibited underground because they are an ignition risk. Contraband incidents occurred at Pike River, despite preventative actions taken by management. Underground vehicles powered by diesel engines incorporated flameproof enclosures to prevent hot surfaces igniting gases, but these systems can be prone to failure. Frictional ignitions caused by metal to metal contact during vehicle or work activity underground could also ignite a gas explosion. The main fan was not flameproof, and other underground electric motors could also have been potential ignition sources.
The site of the ignition
The characteristics of the explosion, its effects upon the two survivors in the drift and computer modelling undertaken by the expert panel indicated that the most plausible ignition site was one inbye of the main fan, in about the middle of the mine workings.
The subsequent explosions
There were three further explosions on the afternoons of 24, 26 and 28 November. These were also methane-fuelled, but were shorter and more violent than the first one. They were probably sited nearer to the main ventilation shaft. The pattern of the explosions indicated that, during the afternoon, air was naturally drawn into the mine from the portal and became mixed with accumulated methane so that an explosive fringe developed. An underground fire or hot coal could then have ignited the explosive atmosphere.
The cause of the deaths
Following an inquest the chief coroner found that the men died ‘at the immediate time of the large explosion … or a very short time thereafter’ from the force of the explosion or the effects of the irrespirable atmosphere.[9] This finding was based on reports from medical experts produced at the inquest. The commission heard additional evidence concerning survivability.
The evidence from a number of mining experts generally supported the inquest finding. Based on the history of similar disasters, the small area of the mine, the force, heat and toxicity of the explosion, and the effects experienced by the survivors in the drift, the experts considered that survival for any appreciable time in the working area of the mine was most unlikely.
Laser images of the FAB taken by a device lowered down the slimline shaft showed that the lid of a box containing self-rescuers was open, raising the suggestion that someone could have survived to open the box. This, however, is only one possible explanation. The lid could have been left open before the explosion, opened by someone afterwards or possibly blown open during the explosion.
The commission considers these suggestions speculative and insufficient to alter the chief coroner’s finding. It agrees that the men probably died at the time of the explosion or a short time after it.
Search, rescue and recovery
The initial emergency response
Pike’s emergency response management plan required the most senior manager on site to take control of any emergency. Within minutes of the 3:45pm explosion the mine manager was told that all reporting from underground had stopped and no one had called the control room – an unprecedented situation. An electrician was sent underground and drove 1500m inbye before a toxic atmosphere forced him to retreat, but not before he saw a vehicle and someone lying on the roadway. He reported this at 4:25pm. Emergency services were then contacted.
It would have been better to call for emergency help once it was clear the situation was unprecedented. Emergency services could have been stood down if necessary. The delay probably made no difference to the survival of the men, but the mine manager was not to know this.
Police assume control
Within the hour local police officers reached the mine and officers at Police National Headquarters in Wellington decided that the police would lead the emergency response. This brought initial order to a very difficult situation as Pike managers, mines rescue crews, the New Zealand Fire Service, DOL, St John Ambulance and others rallied at the mine site.
The next day further New Zealand and Australian mines rescue and mining experts arrived at the mine, their travel needs facilitated by the police, who expertly managed many logistical demands throughout the response effort.
Conducting the emergency response was very complex, given the need to co-ordinate multiple agencies, make crucial decisions and maintain external communications, including with the families, when time was of the essence.
Self-rescue
After an underground fire or explosion coal miners worldwide are trained to self-rescue by walking or driving out of the mine. It is standard practice for miners to carry a self-rescuer, a form of breathing device for use in a toxic atmosphere. The workers at Pike River carried 30-minute duration self-rescuers and were trained to use the drift as the preferred escapeway in an emergency.
As at November 2010 it was the only useable means of egress. Climbing up the 110m ventilation shaft – the designated second egress – would not have been possible wearing a self-rescuer and with the shaft effectively functioning as a chimney after the explosion. As far as is known, the explosion did not cause a roof fall sufficient to block off the drift, so the absence of a second means of egress probably did not affect the men’s chances of survival.
The Mines Rescue Service (MRS)
The MRS operates through a charitable trust to provide training and emergency response services to the mining industry. It is funded from a coal levy and payments received for its ancillary services.
Mines rescue crews were deployed to Pike River immediately after the 4:30pm callout. Throughout the rescue phase local crews made up of volunteer miners, assisted by their Australian counterparts, were on standby, but to their frustration conditions did not permit entry into the mine.
The MRS also played a major role in sealing and using the Queensland MRS inertisation device to stabilise the mine following the sequence of explosions, and successfully led an operation to reclaim and reventilate the first section of the drift in 2011.
The fresh air base (FAB)
During the emergency response reference was made to a place in the mine where the men could be waiting in fresh air to be rescued. This was the stub near Spaghetti Junction and at the bottom of the slimline shaft called the FAB. The methane drainage pipeline passed through the stub, which also contained a supply of spare self-rescuers, and first aid and fire-fighting equipment. There was a roll-down brattice curtain at the entrance, but it did not provide an effective seal. Nor was there any assurance that, following an explosion, fresh air would flow down the slimline shaft.
The stub was an FAB in name only, not a place of safety in an emergency. Nor was it suitable as a changeover station for anyone wanting to don a fresh self-rescuer.
A lack of information
The emergency response was hampered by a lack of information. The number of men missing underground remained uncertain until Saturday morning, 20 November, when the correct figure and the breakdown between employees and contractors was announced.
There could be no rescue attempt without information on the mine atmosphere. Reporting from underground stopped at the time of the explosion and Pike had no back-up system. For the first five days the only samples available for analysis were taken from near the top of the ventilation and slimline shafts, but they were not considered representative of conditions underground. A new borehole drilled into the heart of the mine reached pit bottom on the morning of 24 November. The availability of representative samples stimulated hope, but the second explosion that afternoon put paid to any thought of a rescue attempt.
The window of opportunity fallacy
There has been criticism that rescuers did not go into the mine during a so-called ‘window of opportunity’ when it was supposedly safe to enter immediately after the explosion. The commission rejects this criticism and any suggestion of a lack of courage on the rescuers’ part.
There is no predictable period during which a gassy coal mine may be safely entered before a second explosion may occur. Secondary explosions are unpredictable, and the window of opportunity fallacy has claimed many lives in mines throughout the mining world. International best practice is to re-enter an underground coal mine only on the basis of representative and reliable atmospheric information. This did not exist at Pike River.
Entry into the mine would also have been unusually challenging with no ventilation or second egress, and a 2.3km inclined drift to negotiate.
The co-ordinated incident management system (CIMS)
CIMS is a system designed to co-ordinate the response activities of New Zealand emergency services. CIMS is generic, not specific to mining. A core concept is an incident management team comprising planning/intelligence, operations and logistics managers who formulate an incident action plan. That plan must be approved by an incident controller. The controller and the management team are based close to the incident site, where decisions are made promptly and with the benefit of expert advice.
After the police assumed the lead agency role at Pike River the three management and the incident controller roles were assigned to police officers, meaning the leadership group at the mine lacked mining expertise. Superintendent Gary Knowles, the incident controller, based himself at Greymouth, but was required to refer many decisions to an assistant commissioner at Police National Headquarters in Wellington.
This three-level structure was cumbersome and unsuited to the rapidly changing situation faced by the rescuers at the mine. Instead of decisions being made at Pike River, where mining and rescue experts were gathered, many were made by non-experts in Wellington. This slowed the emergency response and could have impeded a rescue had one proved possible. Preparations to seal the mine to reduce the chances of further explosions were hindered, and some experts at the mine became disillusioned.
The commission considers that management of the response over the crucial rescue period was not in line with CIMS principles. The difficulties experienced highlighted the need for advance planning for an underground coal mining emergency, involving all the relevant agencies, including the MRS.
Recovery of the men’s bodies
After the explosions the mine entrances were sealed and inert gas was pumped underground. This extinguished fires and stabilised the atmosphere, which became methane rich and irrespirable.
In March 2011 the police handed control of the mine to receivers, appointed following Pike’s voluntary receivership. Late that year the receivers, assisted by the MRS, established permanent seals that enabled the drift to be reclaimed and ventilated to 170m inbye of the portal.
In July 2012 Solid Energy New Zealand Ltd purchased the mine and also signed an agreement with the government to recover the bodies as part of any future mining operation if it ‘can be achieved safely, is technically feasible and is financially credible’.[10] The government has a watchdog role, and may also contribute to any recovery costs over and above the costs arising from a resumption of commercial mining.
There is no prescribed timeframe and the risks involved in re-entering the mine workings beyond the drift make body recovery from this area very uncertain.
The families of the men
Attendance at the hearings
The loss of 29 lives at Pike River exacted an enormous toll on the men’s families, friends and colleagues. Many family members attended the commission’s hearings. A number provided written witness statements and some provided heart-breaking oral evidence to the commission. The commission was impressed with their fortitude and courage.
Were false hopes raised?
Some families consider they were given false hope concerning the prospects of their men’s survival. The families were initially briefed twice daily by Superintendent Knowles and Peter Whittall, based on information they received from the mine site shortly beforehand. Over the first weekend Mr Whittall in particular referred to fresh air being pumped into the mine, men waiting underground and the possibility of a rescue attempt when the mine conditions were better understood.
The commission has concluded that Mr Whittall gave false hope, but did not do so deliberately. Although some of his comments were over optimistic, even unwise, they reflected his state of mind at the time. Under extreme stress he allowed his desire for a successful outcome to intrude, showing that someone not so close to the situation should be selected for the spokesperson’s role.
Advice of the second explosion
Superintendent Knowles and Mr Whittall were at the mine at 2:37pm on 24 November when the second explosion occurred. Experts agreed that no one could have survived this even more forceful explosion. People were advised by text message of a ‘significant update’ at the 4:30pm family briefing.[11]
Mr Whittall began by referring to improved gas levels and preparations to go into the mine. This caused great excitement. But as soon as order was restored he referred to the second explosion and Superintendent Knowles added that it was not survivable, so the operation had moved to a recovery phase. The scene turned to one of profound distress.
Mr Whittall agreed that this announcement went horribly wrong. However, the commission accepts his evidence that this outcome was unforeseen and entirely unintended. The stress of the occasion and a few ill-chosen words raised hope before all hope was dashed, but this was a human error.
The recording of the first explosion
The CCTV recording of the first explosion was not shown to the families until Tuesday 23 November. Some were critical of the delay and there was also a suggestion that the recording was edited and was shorter than the original.
The delay, although unfortunate, arose because the recording was not drawn to Mr Whittall’s attention until Sunday 21 November. He then acted promptly in obtaining and arranging for the recording to be shown to the families. The evidence of those who supplied the recording to Mr Whittall confirmed that it was not an edited version.
Body recovery
Following the second explosion most families sought the recovery of the men’s remains above all else. Early comments to the effect that recovery could be only ‘some weeks’ off led to optimism.[12] Then, during 2011, progress towards re-entry into the mine stalled, frustration set in and family members felt that they were alone and unsupported.
The sale of the mine to Solid Energy in 2012 revived hope, but in May the families were told that the prospects of body recovery were remote. They were ill prepared for this news.
The commission received expert evidence that the delay and uncertainty concerning body recovery had hindered the grieving process and increased the toll on many family members. This was clearly evident as relatives gave evidence at a hearing in late 2011, and emphasised the need for communications with families to be both factual and balanced.
Support for family members
The commission acknowledges the outstanding level and value of the support given to the families from the time of the first explosion. Family members expressed heartfelt appreciation for the comfort and assistance they received.
A Pike liaison group, police and Air New Zealand family liaison teams, St John Ambulance, the Red Cross, the Focus Trust, the mayor, churches and people of Greymouth, Tai Poutini Polytechnic, the Salvation Army, central and local government agencies and others offered support in a variety of ways. Based on the lessons learnt from this tragedy, the police are training 40 staff members as victim liaison officers and developing liaison guidelines for major crisis management. This is commendable.
Safety of the mine and the surrounding area
The main shafts into the mine were capped in late 2010, a step towards extinguishing any hot spots underground. In December 2011 permanent steel doors were installed at the mine entrance. The mine atmosphere remains methane rich, and therefore inert. Gas samples taken from six boreholes are continuously monitored.
Control of the mine is now the responsibility of Solid Energy. Access to the site is controlled by a series of security gates and, following a recent review, increased remote monitoring of the site and access road is under development. These steps are sufficient to safeguard the mine in the meantime. If the mine is not to be reopened measures to permanently seal it should be effected by the mine owner in consultation with the local authorities and the land owner.
[8] Kevin Poynter, Operational Review Process Monthly Report – Staff Member, 2 September 2010, DOL3000090046/3.
[9] Counsel’s Submissions and Coroner’s Findings, 27 January 2011, INV.01.27510/8.
[10] Deed relating to body recovery at the Pike River Coal Mine, 17 July 2012, SOL0503445.001/2.
[11] Wendy Robilliard, witness statement, 1 July 2011, POLICE.BRF.54/4, para. 12.
[12] Andrea Vance, Michael Fox and Amy Glass, ‘New Blast Makes Mission More Difficult’, The Press, 29 November 2010, http://www.stuff.co.nz/the-press/news/pike-river-disaster/4399940/New-blast-makes-mission-more-difficult
