Audit 9 Nth Standard Operating Procedure Second Workings September 2016. SPONTANEOUS COMBUSTION; BOREHOLE MANAGEMENT; CHANGE MANAGEMENT RISK ASSESSMENT DEFICIENCIES
9 Nth 2nd workings Audit PB sept 2016
Inspector Paul Brown in September 2016 created this Mine Record Entry in September 2016.
Most of his adverse findings and Recommendations can be be broken down into 3 categories that directly pertain to the Heating and Fire in September 2018.
- SPONTANEOUS COMBUSTION MANAGEMENT
- BOREHOLE MANAGEMENT
- CHANGE MANAGEMENT RISK ASSESSMENT DEFICIENCIES
Straight failures occur such as identifying 38 Boreholes on the Night of the 4/5th October 2018, more than a month since the Emergency began.
In my opinion this openly demonstrate that North Goonyella either took only token/no action or just basically ignored the MRE and Findings of Inspector Brown.
This is further obvious when confusion and in some cases total lack or Reliable Monitoring and Spontaneous Combustion Information and Deficient Procedures.
Inspector Brown required a response by the 29th of September 2016.
Whatever the Response says I am sure it would be enlightening when trying to understand exactly what did/did not occur at North Goonyella exactly 2 years later in 2018
BOREHOLE MANAGEMENT
Step 14. Does not make reference to a standard or a specific procedure for dealing with Borehole’s.
Step 14. Borehole’s are only one source of risk of lightning, risk of Lightning has not been fully addressed, please reference the Blakefield South Mine report 5 January 2011 for most recent information.
Surface Contour Plan
Cemented, Uncemented, Lost, Goaf Drainage Borehole plan
Section 3.8 is only considering one source of lightning risk, again reference the Blakefield report. There is a need to demonstrate why the risk does not exist at North Goonyella Mine.
SPONTANEOUS COMBUSTION
Reference made throughout the Risk Assessment to ‘Atmospheric Monitoring’ must be specific for each situation, i.e. hand held instrument, tube bundle, real
Step 18. Changes in caving of TG end coal does not appear to be considered in spontaneous combustion risk. If it is a change from Longwall 8 North (even a small change) then it must be considered within the risk assessment.
Step 42. No detail on precautions to be taken to minimise the risk of access to potential explosive and or irrespirable atmospheres.
Step 45. There is no reference made to the previous history of Spontaneous Combustion at North Goonyella Mine.
Recommendation –
The document could be complimented with detail about the estimation of extraction achieved with Top Coal Caving.
4 Section 3.5, “Ventilation pressures are set-up to as low as practicable with the aim of maintaining low differential pressures across both active and previous goaves Is this TARP driven for triggers? if not, why not?
CHANGE MANAGEMENT RISK ASSESSMENT DEFICIENCIES
Two signatures missing from Risk Assessment cross section, page 2.
Step 15. Reference made to “Investigate provision of goaf sewer chamber” , if this has not been captured in previous Risk Assessments and is a significant change from normal operations, the concept of a ‘Sewer Chamber’ must be a stand alone Step to be risk assessed within this document.
Step 18. Changes in caving of TG end coal does not appear to be considered in spontaneous combustion risk. If it is a change from Longwall 8 North (even a small change) then it must be considered within the risk assessment.
Recommendation –
- The document could be complimented with detail about the estimation of extraction achieved with Top Coal Caving.
Section 3.5, detail based on known history from Longwall 8N extraction on volumes of gas extraction would be of benefit to this section.
Section 3.5, ventilation modelling detail for Sewer Bleed detail required.
MINE RECORD ENTRY
On 12 September 2016, I received copies of the Standard Operating Procedure Second Workings NC-MIN-SOP-LW318, and the underpinning Workplace Risk Assessment NG-MlN-RSK-LW014 LW9N Secondary Workings, from North Goonyella Mine representative Mr Marek Romanski (UMM).
I have read and considered the documents and make the following observations on which I require a response.
1.0 LW9N Secondary Workings Risk Assessment
Document provided to Inspectorate, NG-MlN-RSK-LW014:
Two signatures missing from Risk Assessment cross section, page 2.
As a general comment for the whole of the Risk Assessment (RA), any references made to a site Standard, Procedure, MOP, TARP, PHMP or SOP must have the full document name recorded within the RA details.
Reference made throughout the Risk Assessment to ‘Atmospheric Monitoring’ must be specific for each situation, i.e. hand held instrument, tube bundle, real
Step 14. Does not make reference to a standard or a specific procedure for dealing with Borehole’s.
Step 14. Borehole’s are only one source of risk of lightning, risk of Lightning has not been fully addressed, please reference the Blakefield South Mine report 5 January 2011 for most recent information.
Step 15. No reference made to volume of known goaf drainage capability and historical data of Longwall 8 Nth.
Step 15. Reference made to “Investigate provision of goaf sewer chamber” , if this has not been captured in previous Risk Assessments and is a significant change from normal operations, the concept of a ‘Sewer Chamber’ must be a stand alone Step to be risk assessed within this document.
Step 16. When referencing ‘Commissioning checks’, detail by reference name of checklist or, template name, procedure, work order type. Any existing controls must not be generalised, if they are not an existing document and have to be generated by a planner then it becomes a proposed control.
Step 18. Changes in caving of TG end coal does not appear to be considered in spontaneous combustion risk. If it is a change from Longwall 8 North (even a small change) then it must be considered within the risk assessment.
Step 42. No detail on precautions to be taken to minimise the risk of access to potential explosive and or irrespirable atmospheres.
Step 45. There is no reference made to the previous history of Spontaneous Combustion at North Goonyella Mine.
Step 46. The current controls are generalised without specific reference, it is not transparent if these controls have been reviewed for Longwall 9 Nth or, if they are specific to the series of longwall. More detail required.
Step 48. Proposed control should reflect application rate per ton extracted and not per hour, reason being the cut rate can vary by shearer speed and face slumping. Inspector Neil Randolph can provide advice for the mine on this matter.
Step 50. Seat Belts are not a control for “Poor road conditions preventing ingress I egress”.
2.0 Longwall 9N, SOP Second Workings
Document provided to Inspectorate NG-MlN-SOP-LW318 :
1 . Recommendation – The document could be complimented with detail about the estimation of extraction achieved with Top Coal Caving.
Recommend adding the detail why the change to position of TG drive was made.
In section 3.3 there needs to be linkage to the Dust Management Plan for double chocking.
4 Section 3.5, “Ventilation pressures are set-up to as low as practicable with the aim of maintaining low differential pressures across both active and previous goaves Is this TARP driven for triggers? if not, why not?
Section 3.5, detail based on known history from Longwall 8N extraction on volumes of gas extraction would be of benefit to this section.
Section 3.5, ventilation modelling detail for Sewer Bleed detail required.
Section 3.6, the first dot point, same comment applicable as point 4 in this MRE.
Section 3.6: the second dot point, detail must reflect statement made in page 61 of the Risk assessment for 300m of retreat as a trigger to review the TARP.
Section 3.6, the third dot point, too generalised, specific locations to be referenced or demonstrated by a plan.
Section 3.8 is only considering one source of lightning risk, again reference the Blakefield report. There is a need to demonstrate why the risk does not exist at North Goonyella Mine.
1 1. Section 3.8.2, last paragraph belongs in section 3.8.1.
Section 4, recommend adding responsibilities specifically for ERZ Controllers and Shift Supervisors, ‘Implement and Monitor of the SOP and related documents.’
Further to the comments made above, I am of the belief the SOP can be further complimented with the following Plans as appendices:
Surface Contour Plan
Seam thickness contour Plan
Seam dip contour Plan
Depth of cover contour Plan
Geological Hazard plan for the specific Panel (9N) Plan
Cemented, Uncemented, Lost, Goaf Drainage Borehole plan
3.0 Summary
It is not the intention of this MRE to question the methods of operation to be employed in regard to mining 9 North longwall but to ensure that the appropriate risk assessment processes have been followed in particular to principal hazards.
A response to the MRE content is required by 29 September 2016.
