A mine fire that burned Peabody Energy’s North Goonyella mine and likely cost the State of Queensland more than 100 Million dollars in coal royalties was overseen by numerous Queensland Government mines inspectors from its’ initial heating event to a raging fire that saw the mine close and hundreds of miners and contractors lose their jobs.
AMSJ has learned Queensland Government mines inspectors stood overseeing the leadup to the event and ‘giving advice’ to Peabody Energy that may have contributed to the loss of the mine.
Records uncovered by AMSJ show that mines inspectors attended the Peabody mine and met with Peabody personnel from the 3rd September 2018 (almost one month prior the eventual public disclosure of the mine fire) to discuss high Carbon Monoxide (CO) levels in the 9N tailgate area of the mine. Inspectors and the mine operator agreed to provide a detailed timeline of the events leading up to the high CO incident and establish a large Floxal unit onto a gas riser at the tailgate end of the working face.
One day later the inspector returned to the mine and methane levels were rising (from 12.6% to 14.02% but CO levels from the tube bundle system had fallen marginally from 586 ppm to 447 ppm. The mine had previously been evacuated and Peabody Energy gave advice to the mines inspector that conditions were improving. The mines inspector noted that “there was good discussion concerning the way forward.”
The inspector was informed of the plan, once miners were underground, to seal off the tailgate and inject Floxal in through the seal to completely inert the end of the tailgate face. The mine also planned to examine the use of a foam generator to facilitate the injection of inert gas via the Floxal unit into the mine to prevent the heating increasing.
On the 5th September, an agreement was made with the mines inspector and Peabody regarding the plan to bag off the tailgate hatch and flush gas from the tailgate end of the goaf. Meantime Peabody had sort to mobilise two additional Floxal units from NSW.
Again, on the next day, 6th September 2020, two mines inspectors returned to the mine. CO, Oxygen, Hydrogen and Ethylene were dropping but one of the inspectors suggested that that the mine consider controlling access as the situation was “in effect” an emergency. Peabody Energy agreed.
The mine had planned conduct a risk assessment on the establishment of a 400-metre borehole to the source of the heating and to complete an additional risk assessment with the Industry Safety & Health Representative to implement a controlled re-entry to the mine.
An inspector recommended to Peabody that planned TARPS be implemented to withdraw people if critical levels were reached. But alarmingly, the mines inspector made specific recommendations on the use of the sealing management plan. The inspector recommended that the mine consider reviewing the sealing management plan when the shield recovery progressed past the maingate chute road. The maingatre chute road was to be used as a return for future recovery.
Inspector morphs from mine safety regulator to mine advisor/consultant
It appears at this point the mines inspector then became embedded in solving the problems at the mine rather than regulating aspects of critical safety. AMSJ has previously been informed by Queensland Mines Inspectorate that inspectors were not involved in decisions at the mine but on the 6th September, evidence suggests that specific advice began to be provided.
By the 7th of September at 1.30 pm, ERZ controllers had gone underground and around 6.30 pm they had completed an inspection of the mine. The controllers reported is issues with water particularly at the 17 cut-through of being 600mm from the roof and that methane in development heading was relatively low.
The mines inspector said in a report that gas levels showed “no issue of concern” despite CO being at 160 ppm in the tailgate chute road and the end of the face indicating 280 ppm. He was concerned with Peabody’s TARPs remarking that the TARPS were “not completely relevant due to the mine’s situation.” He requested a revised sealing plan in view of the changes to conditions in the mine.
Peabody was vigorously pumping inert gas into the mine using Floxal units connected to the sealed goaf via boreholes and was still waiting for the arrival of a large Floxal unit from NSW to continue inertisation of the goaf and the borehole drilling to the source of the spontaneous combustion was underway.
On the 8th September, an inspector returned to the mine and met with nine of the mine site’s leadership team. Water had been building up in the mine with pumps and other electrical sources isolated due to concern over ignitions. But there were early indicators of problems. The inspector wrote that “when a Floxal unit had been turned off for repairs, CO at the end of the tailgate rose quickly from 131 ppm to 265ppm and was still rising.” Methane dropped and Oxygen jumped.
There had also been a loss of circulation in the borehole drilling at 232m potentially due to subsidence cracks appearing from the goaf where the drillers were trying to pinpoint the location of the heating. The mines inspector agreed that “the best way forward was to place a thick grout in the drill hole to prevent leakage from the cracks and then continue drilling. But advised that the process may need to be completed several times in order to prevent leakage into the drill hole.
The mine had begun implementing and modifying TARPS to undertake essential works underground, but the inspector advised the mine that they should consider which activities would be deemed “essential” in view of the situation emerging. The mine advised that underground works would be a “volunteer only” activity.
On the 9th September, the inspector appeared upbeat with tube bundle results trending down albeit slowly. The inspector writes “all fluctuations in the past 24 hours can be explained and accounted for.” He joins a site meeting by teleconference regarding the use of higher capacity Floxal units at the mine.
There may have been an upbeat mood emerging as levels were trending down and the Queensland Government’s Simtars has monitoring team had arrived on site. ERZ controllers were continuing inspections and the mine was seeking to risk assess repowering the longwall.
By the 10th September, the Simtars team’s Gas Chromatograph was reading higher CO (+20 ppm) levels of gas than the North Goonyella unit. The mine was continuing to inject Floxal and commenced injecting the inert gas into the borehole being constructed. Gas readings were indicating that there was an indication of spontaneous combustion coming from the main gate side of the chute road. Peabody had mobilised QMRS, Simtars, engaged expert gas consultants by the 10th September but was reporting that the situation was routine to the market.
By the 11th September, there were clear signs that conditions were not as expected. One of the Floxal units injecting into the maingate was not injecting into the goaf rather it was injecting into the pressure chamber at the seals. An urgent call was reportedly made to the Queensland Government mines inspector during the night and the inspector approved a plan to open valves to permit inert gas into the goaf.
“We held a discussion about going forward. The mine is working on options should the inertisation alone not be able to control the situation.”Queensland Mines Inspector
The mine was also scrambling to prepare to drill two additional holes with two separate rigs into the goaf to allow further inertisation of the goaf. The QMRS foam generator was also connected into one the boreholes at the tailgate end of the goaf.
The inspector had continued to receive gas data spreadsheet and Incident Action Plans from Peabody Energy and by now was firmly embedded in the Peabody operation and it was apparent that he was being used a point of expert reference for managing the unfolding situation.
Grappling with high CO
By the 12th of September, the mine was still grappling with high CO levels. In the tailgate chute road, the CO had reached as high as 448pm but was varying significantly. Graham’s Ratio showed peaks and reductions.
The mines inspector stated “we held a discussion about going forward. The mine is working on options should the inertisation alone not be able to control the situation.”
Day by day the records on the mine’s emerging situation continued to evolve and problems were developing. On the 14th the mine confirmed that a new hole being drilled into the goaf was, in fact, incorrect and needed to be redrilled into the desired location. By the 15th September CO in the TG chute was up at 470 ppm. There were different results in gas monitoring being obtained between the Queensland Government’s Simtars Gas Chromatograph and the mine site’s Gas Chromatograph. The inspector identified obvious errors in ventilation models being used. Daily site meeting involved a large range of personnel including an expert from Simtars and other consultants.
By the 17th, three Government mines inspectors had turned up at the site together with the Queensland Government’s Simtars personnel. The Tailgate Chute road was now at 600 ppm (with suspected failed coupling from Floxal unit being attributed to the increase). Peabody’s strategy moving forward involved mobilising a rig to plug the chute road. The mines inspectors were concerned expressing that “if the tailgate chute road was plugged a formal risk assessment must be conducted.”
Mines minister remains uninformed
Despite the unfolding situation, the Queensland mines minister wasn’t reportedly informed about the incident according to his office at the time. AMSJ submitted FOI requests and was advised that during the process the mines minister was not formally briefed on the evolving disaster. In fact, ultimately information relating to the event was refused to be released to AMSJ on the basis of an ongoing investigation. That investigation may have now been finalised almost two years after the event.
On the 19th a meeting convened by Peabody and attended by the Deputy Chief Inspector of Mines, two mines inspectors and two experts from the Government’s Simtars heard the gas reading CO make was variable between tube bundle points. The meeting discussed “explosibility risk and unknown explosibility environments around what was now referred to as a “heating event.”
By the 23rd a tube bundle result went from 550 ppm to 745 ppm and hydrocarbons, presumable ethylene was present. Inspectors now referred to the event as a spontaneous combustion. The Narrabri (NSW) Floxal unit had still not arrived and the chute road sealing was still on the table. There was also a requirement to recalibrate ethe tube bundle system.
Government personnel descend on mine in lead up to smoke billowing from portal
Queensland Government personnel descended on the mine on the 27th September 2018 for a 8.30 am meeting.
There were now four Government mines inspectors and two personnel from the Government’s Simtars Gas Unit together with the head of Peabody’s Australian Operations. The tone had changed. The mine had turned off the power in order to prevent an explosion but the QMRS’ GAG engine used to rapidly inertise the mine had not been deployed despite solid indicators of a mine fire.
At around 6 pm on the 27th of September at 6 pm, thick black smoke was emanating from the main fan shaft. That continued the next morning with inspectors noting volumes of black smoke coming from the belt drift, the main fan.
Finally, on the 27th September and inspector gave a Directive under Section 125 of the Coal Mining Safety & Health Act to suspend operations and withdraw from an exclusion zone until an acceptable level of risk was achieved.
At around 11.00 pm on the 28th the Department officers then issued a directive to not enter past the locked gate of the mine. The mine was on fire but, according to a Freedom of information request submitted by AMSJ, the Minister’s office had not received a briefing note on the event.
Over the forthcoming weeks we intend to expose the circumstances between the 23rd September and 27th September which saw the mine transition from a heating to an outright mine fire.
On 18th September 2020, almost two years after the event, the Queensland Mines Inspectorate (now Resources Safety & Health Queensland) told the Mackay Daily Mercury that the investigation into the event had been finalised.
The Queensland government now considering compliance activity
“The Queensland Mines Inspectorate is currently considering potential compliance activity in relation to this incident,” the spokesman said.
“Preliminary findings from the incident were released on August 9, 2019, and further information about the investigation will be published once the compliance process has finalised.”
A time frame for when this compliance activity process would be finalised was not provided by Queensland Resources Safety & Health.
Shadow Mines Minister, Dale Last told AMSJ this week that “The investigation into North Goonyella has gone nowhere for years because some witnesses, including government staff, won’t give evidence.”
From our investigation into the North Goonyella mine fire event, we clearly understand why!
Read more Mining Safety News
Notes: AMSJ has provided this article for informational purposes. The information contained within the article is factually correct but is not intended to be evidence for a Court or Board of Inquiry. Other factors may have affected inspectorate decisions that we were not privy to as part of our investigation. We reiterate the article is informational only and the outcome of a legal investigation may impact the findings within this story.