North Goonyella Mine Fire 10th October 2018. “One of the in seam drainage blow skids was found to be breathing in. This indicates that the water trap underground has blown out and the gas could be free venting into the Mine atmosphere. Dennis Black stated that they would attempt to fill the riser and attempt to refill the water trap in this manner”
MRE – North Goonyella – 10.10.2018.pdf
H9 temperature at 59 degrees C, drone with thermal indicator to be used as a check.
This has gone up from the first reading of 42 degrees C taken on the 6th October.
Bleeder fan showed 24% methane and usual reversal when the GAG was not running — goaf gas, methane, in the bleeder road is usually at 1.3% in 46 cubic metres.
E44 shows fresh air — to be replaced as a sampling point.
- Brady noted a correlation between 36Ct and H9 readings when the GAG was off and also C02 step change up to 1%(unexplained) in GN2698 (hole in goaf opposite TG Chute road.
Quantity at H9 still not known.
We were informed that one of the in seam drainage blow skids was found to be breathing in. This indicates that the water trap underground has blown out and the gas could be free venting into the Mine atmosphere. Dennis Black stated that they would attempt to fill the riser and attempt to refill the water trap in this manner
Les Marlborough asked for an explanation of the logic behind the current inertisation strategy with the Floxal injection. He noted that the only Floxal gas going into the 9N Goaf was that going in through MG9N 3 CT and he did not understand why the Mine was not injecting more Floxal gas into the Goaf.
It was explained that the strategy was founded on not pushing methane out over the heating. Les Marlborough stated that with 25% Methane at H9 shaft the methane was already being flushed out of the goaf. Mr Romanski stated that he did not want to inject Floxal gas with 3% oxygen into the goaf area. Les Marlborough explained that the Floxal units can be adjusted so that the flow from the unit is reduced and the oxygen content is lowered to between 1 and 2%. Les Marlborough stated that, as part of the Mine Record Entry from today there would be a recommendation for the Mine to review the Floxal strategy.
Les Marlborough asked about how well developed the Mine medium and longer term strategy has been developed — Mike Carter undertook to give details after the meeting.
Martin Watkinson gave an update upon the potential to provide a suitable cable for the camera which is likely to take two weeks.
RECOMMENDATION
Inertisation Strategy using a Floxal unit during NGC Mine NIA spontaneous combustion/fire emergency
The Mine is recommended to review the Floxal strategy in relation to inertisation of 9N goaf.
Inspector Richard Gouldstone arrived at NGC Mine Camp at 07:15am on Wednesday 10 October 2018 to attend a meeting in regard to progress on dealing with the spontaneous combustion and subsequent underground fire. Inspector Les Marlborough arrived shortly afterwards.
Update Meeting NGC Camp @ 8:30am present
Les Marlborough (Mines Inspector)
Richard Gouldstone (Mines Inspector) Mike Carter (Millennium SSE — IMT member)
John Anger (SSE)
Peter Baker (Peabody Operations Manager)
Dennis Black (VO)
Marek Romanski (UMM)
John Fitzpatrick (MSO)
Casey Moore (ISHR)
Neville Impson (Compliance Manager)
Josh Cook (Graduate Mining Engineer)
By dial in
David Cliff (Consultant)
Darren Brady (Consultant)
Luca Rocchi (Chief Inspector of Mines)
Shaun Dobson (Deputy Chief Inspector)
Martin Watkinson (Simtars)
11/10/2018 I Of
No major changes in direction in the last 24 hours
Last 24 Hours
- Gag running at 11:10 am after maintenance from 6:45am and encountered problems with over-temperature/ fuel pressure 4:10pm to 10:15pm, 48 hours shutdown now arranged earlier than planned for 12 October.
- MG belt road plug in place(Sat pm/Sun am).
- Borehole GN2703 (MG A Hdg 2 CT) — now plugged 234 cubic metres placed. This leaves only MG chute to plug plus TG to add to the incomplete seal already in place.
- Borehole GN2701 (MG Chute Road) — ready for plugging but problems of maintaining the hole still persist after reaming and kinked hoses in hole estimate Friday before this will be completed.
- GN2704 (TG Roadway) — Down to seam and ready to set up for pumping seal. • GN2705 Rig 1226/1265 swapped due to hole design and rig capability now down 365m.(MG Chute concrete seal preparation).
Floxal Unit #6 set up over 42 CT (Stone Dust Silo) @ 7501/s. This running continuously. e Floxal Unit #2 at 6 CT in the Corridor. Run all night @ 3201/s. This running continuously.
e Borehole monitoring, 1-19 4 hourly, GN2700, 1946, 2695, 2698, 36CtD„E, 25Ct 9N and 44Ct E Hdg (unreliable samples thought to be emulsion product) all at 6 hourly intervals.
- Emergency sealing prep works continued at H40 & 1 in 4
H9 temperature at 59 degrees C, drone with thermal indicator to be used as a check
- UIS flaring 2Ct Ct MGIOS.
Next 24 Hours
Continue GAG operations, afternoon maintenance window may be conducted to avoid hottest part of the day
GN2703 then GN2701 Rocksil Plug works
Continue drilling for LW containment concrete seals to compliment the rocsil plugs
Continue Sampling Regime and seek replacement for 44E
Revise Floxal Strategy — no plan to increase inertisation of goaf, NGC unit into 3Ct only
Preparation of sealing strategy
Conducting prep work for Radon heat survey
Gas flare maintenance planned
IMT change over today
Discussion
Latest H9 results showing slight blip in readings proved to be a transient.
Bleeder fan showed 24% methane and usual reversal when the GAG was not running — goaf gas, methane, in the bleeder road is usually at 1.3% in 46 cubic metres.
E44 shows fresh air — to be replaced as a sampling point.
- Brady noted a correlation between 36Ct and H9 readings when the GAG was off and also C02 step change up to 1%(unexplained) in GN2698 (hole in goaf opposite TG Chute road.
Quantity at H9 still not known.
It is still accepted that with the uncertainty of the status of VCDs potential impacts of changes will be difficult to predict Plugging of all access to LW9 should prove most informative, subject to the status of the two TG seals/plugs.
We were informed that one of the in seam drainage blow skids was found to be breathing in. This indicates that the water trap underground has blown out and the gas could be free venting into the Mine atmosphere. Dennis Black stated that they would attempt to fill the riser and attempt to refill the water trap in this manner
Les Marlborough asked for an explanation of the logic behind the current inertisation strategy with the Floxal injection. He noted that the only Floxal gas going into the 9N Goaf was that going in through MG9N 3 CT and he did not understand why the Mine was not injecting more Floxal gas into the Goaf.
It was explained that the strategy was founded on not pushing methane out over the heating. Les Marlborough stated that with 25% Methane at H9 shaft the methane was already being flushed out of the goaf. Mr Romanski stated that he did not want to inject Floxal gas with 3% oxygen into the goaf area. Les Marlborough explained that the Floxal units can be adjusted so that the flow from the unit is reduced and the oxygen content is lowered to between 1 and 2%. Les Marlborough stated that, as part of the Mine Record Entry from today there would be a recommendation for the Mine to review the Floxal strategy.
Les Marlborough asked about how well developed the Mine medium and longer term strategy has been developed — Mike Carter undertook to give details after the meeting.
Martin Watkinson gave an update upon the potential to provide a suitable cable for the camera which is likely to take two weeks.
11/10/2018 of
Number Recommendation Due Date
Inertisation Strategy using a Floxal unit during NGC Mine NIA spontaneous combustion/fire emergency
The Mine is recommended to review the Floxal strategy in relation to inertisation of 9N goaf.
Please provide a written status report on each SCP together with the actions taken to address each item by their due dates
Please provide a written status report on each Directive together with the actions taken to address each item by their due dates
Please provide a written status report on each Directive and SCP together with the actions taken to address each item by their due dates
