FIRE PREVENTION AND MITIGATION MEASURES ADOPTED AT THE HAZELWOOD MINE
THE HAZELWOOD MINE LICENCE
Coal mining activities in Victoria are regulated under the Mineral Resources (Sustainable Development) Act 1990 (Vic) (Mineral Resources Act), and related regulations. Under s. 8(1)(a) of the Mineral Resources Act, a person cannot carry out mining in Victoria without obtaining a mining licence. The mine licensing regime is discussed in detail in Chapter 3.2 Regulation of fire risk at the Hazelwood mine.
The Governor in Council approved mining licence number 5004 for the Hazelwood mine on 10 May 1996.1 On 10 September 1996, the original licence was revoked and the Governor in Council:
- granted a new mining licence number 5004 for a term of 30 years
- approved an authority to commence work
- approved a work plan and a rehabilitation plan.2
The mining licence contained a schedule of conditions relevant to environmental matters such as drainage and discharge, groundwater, dust and noise, and operational matters such as roads, fencing, security, car parking and royalties.3
The primary obligation under the schedule of conditions to the mining licence is that work at the mine is carried out in accordance with the approved work plan (incorporating a rehabilitation plan), as amended from time to time in accordance with the Mineral Resources Act.4
The obligation under the schedule of conditions reflects a licensee’s obligations under s. 39 of the Mineral Resources Act to comply with any conditions on the mining licence and the approved work plan, and to work in accordance with the approved work plan.
The following conditions on the licence are also of particular relevance:
15. PROGRESSIVE REHABILITATION
15.1 Progressive reclamation will be conducted as per the rehabilitation plan. In addition, any further rehabilitation work will be carried out at the direction of an Inspector.
15.2 As and when directed by an Inspector of Mines, despite any compensation agreements between the licensee and the owner of any private land in the licence, the licensee shall undertake progressive reclamation of land on the area subject to surface disturbance.
16. FINAL REHABILITATION
16.1 Final reclamation will be in accordance with the rehabilitation plan and any additional requirements as directed by an Inspector.
16.2 Failure to complete works in accordance with the rehabilitation plan or in accordance with the directions of an Inspector, shall constitute grounds upon which the rehabilitation bond may be forfeited either in whole or in part in accordance with Section 83 of the MRD Act [Mineral Resources Act].5
On 11 July 2006, mining licence number 5004 was amalgamated with mining licences 5449–5452 and varied to permit mining to take place on the west field of the Hazelwood mine, and to require the licensee to spend $667,930 per annum on mining work in the licensed area.6
APPROVED WORK PLAN FOR THE HAZELWOOD MINE
Work plan – 1996
The work plan for the Hazelwood mine approved on 10 September 1996 has since been varied seven times, with the latest and most substantial variation being approved in 2009.7
The 1996 work plan reflected the ‘Work Plan Submission’ submitted by Hazelwood Power Corporation on 1 June 1995.8
The following clauses of that work plan submission address the risk of fire at the Hazelwood mine:
7.4 Bushfire Mitigation Program
In recognition of the fact that the Mine is situated in high bushfire risk area and the potential consequences on the Mine infrastructure of a bushfire, [Hazelwood Power Corporation] contributes to funding a Bushfire Mitigation Program in the area surrounding the mine. The Bushfire Mitigation Program conforms with the “Latrobe Valley Open Cut Mines – Fire Service Policy and Code of Practice” – see Section 7.7 below.
7.5 Emergency Response Plan
[Hazelwood Power Corporation] has developed an Emergency Response Plan to be followed in the event of an emergency such as fire or flood, catastrophic failure of Mine or plant, bomb threats, hazardous materials etc.
7.6 Fire Instructions
As part of Fire Prevention management [Hazelwood Power Corporation] has promulgated a set of Fire Instructions for Mine personnel, these instructions are updated prior to every fire season – usually in December. Prior to the fire season each year all Mine personnel are required to undertake fire training conducted by the Mine’s fire service section. The Fire Instructions are incorporated as part of the Mine’s Emergency Control Plan.
7.7 Fire Protection Policy
[Hazelwood Power Corporation] adheres to the “Latrobe Valley Open Cut Mines – Fire Service Policy and Code of Practice” issued April 1994 for the Mine, bunkers and their surroundings to ensure adequate:
- Management Accountability
- Preparedness and Planning
- Training of Personnel
- Installed Fire Protection Systems
- Fire Extinguishing Capability
- Emergency Procedures.
The Fire Service Policy and Code of Practice contains the essential requirements and operating procedures for fire protection services for the Mine and its surrounding area.
An extensive network of water reticulation and sprays has been established in the Mine for fire protection.
Refer Figure 13A: “Fire Service Network Schematic”9
The Mine Fire Service Policy and Code of Practice is discussed in further detail below. Figure 13A to the 1996 work plan is depicted in Figure 3.5 below.
Figure 3.5 Fire service network schematic for the Hazelwood mine – Figure 13A to 1996 work plan10
Work plan variation – 2009
On 8 February 2008, GDF Suez applied to vary the work plan in order to allow the expansion of mining in the west field of the Hazelwood mine.11 A delegate of the Department Head of the Mining Regulator approved the work plan variation on 11 May 2009.12
The objective of the west field development was to ensure an uninterrupted supply of coal to the Hazelwood Power Station beyond 2009. It involved two phases:
- Phase 1 involved mining areas of the west field known as block 1A and 1B, which fell within the existing licence boundaries and had already commenced in February 2004.
- Phase 2 involved an expansion beyond the initial boundaries of mining licence number 5004 into areas designated block 1C, 2A, 2B, 3 and 4. Four new mining licences were issued to expand the mine licence boundaries (which were subsequently amalgamated into mining licence number 5004, as noted above).13
The work plan variation was required in order to expand into phase 2 of the west field development.14
The mine blocks for phase 1 and phase 2 of the west field development are depicted in Figure 3.6 below.
Figure 3.6 West field development at the Hazelwood mine15
The 2009 work plan variation provides that mining of overburden and coal as part of the phase 2 west field development will be carried out according to the schedule in Figure 3.7 below.
Figure 3.7 Mining schedule for phase two of west field development16
|1C||2010 to 2015||2011 to 2019|
|2A||2016 to 2017||2018 to 2021|
|2B||2018 to 2025||2019 to 2028|
|3||2026 to 2028||2027 to 2031|
|4||2028||2027 to 2031|
Mr James Faithful, GDF Suez Technical Services Manager–Mine, explained to the Board that ‘references to “overburden mining” [in the work plan] refer to the removal of the soil/clay material overlying the coal… [and] “coal mining” means the mining operations in relation to the on average 100 metre thick coal seam underlying the overburden.’17 Mr Faithful also confirmed that block 1C is still being mined.18
The work plan proposes that the fire management for the west field development ‘will be a continuation of existing methods, and generally comply with the Latrobe Valley Open Cut Fire Protection Policy.’19
As noted in Chapter 3.2 Regulation of fire risk at the Hazelwood mine, at the time that the 2009 work plan variation was prepared, work plans were required to include a health and safety management plan.20 Section 9.1 of the 2009 work plan variation states that GDF Suez:
- is compliant with Australian and New Zealand Standard 4801:2001 ‘Occupational health and safety management systems –Specification with guidance for use’ (AS4801)
- has developed a range of policies, which relevantly includes the ‘Mine Fire Service Policy
and Code of Practice.’21
The health and safety management plan also refers to a risk assessment undertaken by GDF Suez in 2003 to identify major occupational, health and safety mining hazards associated with the development of the west field.22 This risk assessment was conducted in order to fulfil the work plan criteria required under the Mineral Resources Development Regulations 2002 and the obligation to conduct a safety assessment of major mining hazards under the Occupational Health and Safety (Mines) Regulations 2002 (as it then was).23 As part of the risk assessment, ‘major mine plant fire’ is identified as a potential major mining hazard.
The 2003 risk assessment/safety assessment is explored in further detail under the heading ‘Safety assessment’ below.
APPROVED REHABILITATION PLAN FOR THE HAZELWOOD MINE
Rehabilitation plan – 1996
The 1996 work plan includes a rehabilitation plan that addresses both final rehabilitation and progressive rehabilitation. Hazelwood Power Corporation’s 1995 work plan submission (which forms part of the 1996 work plan) described the goal of rehabilitation as follows:
Hazelwood Power Corporation has made a strong commitment to rehabilitate land disturbed by mining operations in accordance with community expectations.
The Mine has a long standing policy to ensure that all land disturbed by mining is stabilised and landscaped to blend into or complement natural features. This policy was developed in consultation with government agencies, special interest groups and the public, chiefly through the Rehabilitation Consultative Group, which meets quarterly.24
Final rehabilitation of the mine was reflected in a ‘Rehabilitation Concept Master Plan’, which envisaged that ultimately the worked out part of the Hazelwood mine would be flooded to form a lake and the surrounding areas could be used for grazing, conservation, active and passive recreation, wetlands habitat and forestry.25 In 1996, only preliminary studies into the creation of a lake had been carried out.26
The Rehabilitation Concept Master Plan contains a ‘Mine Rehabilitation Policy’, which provides directives for three phases of mine operation as follows:
(i) Operational Phase
Where physically practical, screen operational work areas to minimise visual intrusion and minimise disturbance to waterways, vegetation and landforms in nonoperational areas.
(ii) Post Operational Phase
During the life of the project, progressively, and at the earliest practical opportunity after land is no longer required for operations – shape, landscape, revegetate and return disturbed land to its pre-mined capability for agricultural and silvicultural uses in order to:
- stabilise slopes
- manage water runoff to control erosion
- provide a sustainable landform and vegetation pattern that blends into or complements the existing natural features of the region
- provide ultimately for other sustainable beneficial uses
- comply with the Rehabilitation Master Plan.
(iii) Mine Closure Phase
With mine closure imminent, consolidate activities of the post operational phase and liaise with agencies and the public to ensure that:
- sustainable beneficial land uses have been achieved
- rehabilitated land is safe to return to public or private holding.27
In terms of progressive rehabilitation at the Hazelwood mine, a ‘5 year Rolling Implementation Plan’ was prepared with the aim of scheduling ongoing rehabilitation to a five year projection and revising the plan annually or as required.28
The initial five year Rolling Implementation Plan for the period 1996 to 2000, depicted in Figure 3.8 below, envisaged that several sections of the worked out areas of the Hazelwood mine (including small sections of the northern and eastern batters indicated with shading in Figure 3.8) would be the subject of rehabilitation works. No evidence was provided to the Board to explain the extent to which rehabilitation was carried out in accordance with this early plan.
Figure 3.8 Rehabilitation Master Plan—Five Year Program 1996–200029
Rehabilitation plan variation – 2009
Section 6 of the 2009 work plan also addresses rehabilitation. The goal for rehabilitation of the mine is described as ‘a technically feasible, safe, stable and sustainable landscape that reflects the aspirations of stakeholders within the practical constraints of rehabilitation for the mine.’30 This goal required the following objectives to be met:
- a safe and stable self-supporting structure
- maximise the opportunities for establishment of a self-sustaining ecosystem
- minimise the use of natural resources
- minimise the cost of recovery of resources.31
The 2009 work plan identified several issues for consideration in developing and implementing the rehabilitation plan:
- mine stability
- natural equilibrium
- batter stability
- rehabilitation material/ecosystem function
- resource recovery
- public safety.32
Section 6.5 of the 2009 work plan deals with progressive rehabilitation at the Hazelwood mine. Importantly, this section acknowledges the role that progressive rehabilitation can play in fire prevention:
There are 2 major tasks to be completed using overburden:
1. coverage of coal batters to provide fire protection and a nutrient base to support plant growth that in turn provide long term batter stability
2. placement of the balance of overburden material on the floor of the mine to assist with counterbalancing aquifer pressures.33
Ms Kylie White, Executive Director of the Earth Resources Regulation Branch of the Department of State Development, Business and Innovation,34 confirmed that it is ‘still the requirement that during the life of the mine progressive rehabilitation occur at the earliest practical opportunity after the land is no longer required for operations,’35 reflecting the post-operative rehabilitation requirements of the Mine Rehabilitation Policy described in the 1996 work plan.
Mr Faithful provided the Board with evidence regarding the steps required as part of rehabilitation. As a preliminary matter, worked out batters must be ‘reshaped’ as part of rehabilitation, that is, laid back and re-profiled, in order to:
- ensure the stability of soil placed on the batters
- enable revegetation
- make the area visually compatible with surrounding land
- make the areas capable of being used by the public and for other purposes post closure.36
He explained that worked out batters at the Hazelwood mine are typically at a slope of about 1H:1V (ie one metre horizontal for every one metre vertical) and must be progressively laid back to a slope of no steeper than 2.5H:1V and preferably 3H:1V.37
According to Mr Faithful, the steps involved in rehabilitation are:
- Stability assessments: Stability assessments take the current known stability of the batters and then model the stability level after the proposed rehabilitation is completed. A range of variables, including batter profiles, groundwater levels, seismic events, and weather events are simulated to determine how the rehabilitated batters would perform under varying load conditions. Once that assessment is undertaken, controls such as horizontal bores, open drains and vertical pumping bores are then simulated to ensure that the resulting batter safety factors are not compromised.
- Planning: Based on the desired batter profile (or ‘steepness’), the extent to which the existing batters need to be laid back has to be determined.
- Identification and removal or relocation of mining infrastructure: Depending on what the infrastructure is, and what stage of the mining sequence has been reached, infrastructure that is required for the ongoing operation of the mine may need to be rebuilt in a different location.
- Removal of coal and overburden and reshaping: This work is completed using a method called “truck and shovel”. Excavators (shovels) are used to progressively remove the coal and the overburden from each of the levels and this material is carted away in trucks. This is the most complex process.
- Covering with overburden: The layer of overburden is typically about one metre deep.
- Revegetation: After the batters are reshaped, and covered in suitable overburden, topsoil is spread on the area and the area is revegetated. Any necessary geotechnical equipment (eg horizontal bores, standpipes, inclinometers, extensometers) is installed.38
Mr Faithful also identified a number of practical constraints faced by GDF Suez in planning areas for progressive rehabilitation:
- Availability of sufficient quantities of suitable overburden: The composition of the overburden (dirt and clay overlaying the coal, utilised in rehabilitation works) varies throughout the Hazelwood mine. Overburden is not always suitable for placement on batters. Further, only a certain volume of overburden is available from recent mining operations conducted within the mine. Additional suitable overburden material may have to be located.
- Construction constraints: Typically, given the ground conditions at the mine, “earthworks” projects such as rehabilitating batters can only be carried out between November and April due to difficulties with the wet weather outside of this period. In the Latrobe Valley, the earthworks season is generally limited to the period from Melbourne Cup Day to Anzac Day.
- Infrastructure positioned on the northern batters: Important infrastructure is situated on the northern batters, which would need to be removed in order for the rehabilitation works to be completed. Such infrastructure includes power lines, fire services mains pipes, pumps, ponds and groynes, roads, ramps and benches, bores, other geotechnical equipment and roadside/underground drains.
- Infrastructure positioned north of the northern batters: In order to reduce the grade of the batter and allow for future land use, an area of land at the top of the batter would need to be removed. Mine infrastructure and other infrastructure (ie SP Ausnet’s high voltage power lines which service Morwell and other towns, the Princes Freeway and the Morwell Main Drain) are likely to be affected by such works and would need to be assessed and managed (including with third parties).
- Future mining direction: Mining will eventually proceed further to the north at the western end of the Hazelwood mine. The batters at the western end of the northern batters are temporary batters, which will be directly mined through. Any overburden placed over the top of these batters as part of rehabilitation works would need to be later removed.39
The 2009 work plan recognises the requirement for suitable overburden material as a potential obstacle to progressive rehabilitation. Overburden from blocks 1A, 1B and 1C comprise significant volumes of fine grained sands from the former Morwell River valley, which are saturated and are only suitable for batter coverage if given sufficient time for the water content to dissipate. The proposed mine sequencing would not allow sufficient time for dissipation of the water content to occur, so the overburden from these blocks was only deemed suitable for placement on the mine floor.40
Under the 2009 work plan, the planned sequencing of progressive rehabilitation is directly linked to the nature of the overburden as it becomes available from mining operations.41
The first area designated for rehabilitation at the end of mining block 1C is shaded in red in Figure 3.9 below. The area at the eastern end of the northern batters corresponds with an area that was significantly affected by the Hazelwood mine fire.42
Figure 3.9 Progressive rehabilitation staging/sequencing – rehabilitation at end of
block 1C (2019)43
Suitable overburden material for the first stage of progressive rehabilitation will only become available once overburden mining operations move into block 2A, currently scheduled for 2016–2017 and block 2B, scheduled for 2018.44
Overburden materials from block 2B mining operations are inherently more stable and have been scheduled for use in rehabilitation works on the eastern and southern batters at the conclusion of operations in block 2B in 2028 (Figure 3.10).45
Figure 3.10 Progressive rehabilitation staging/sequencing – rehabilitation at end of
block 2B (2028)46
The final stages of rehabilitation are planned to take place at the end of mining block 3 and 4 in 2031 (Figures 3.11 and 3.12).
Figure 3.11 Progressive rehabilitation staging/sequencing – rehabilitation at end of
block 3 (2031)47
Figure 3.12 Progressive rehabilitation staging/sequencing – rehabilitation at end of
block 4 (2031)48
Prior to GDF Suez formally applying to vary the work plan, the proposed expansion at the Hazelwood mine also involved the preparation and assessment of an Environment Effects Statement (EES) amendment to the Latrobe Planning Scheme and four planning permits.49
The panel commissioned to assess the EES and the Latrobe Planning Scheme amendment conducted hearings in 2004 and 2005, in which rehabilitation issues formed a key component.50 The panel found that:
The potential for long-term degradation of the environment will depend on the actions taken as part of the rehabilitation process. For example, instability of the mine could impact on the local surface and subsurface drainage systems. The mine could also be a source of dust unless the revegetation is successful. Unless the risk of fire from the ignition and subsequent slow combustion of coal remaining within the mine void are minimised, smoke could be a significant nuisance. An extreme possibility of an off-site effect is the escape of a fire in the mine area into surrounding land.51
Progress of rehabilitation undertaken at the Hazelwood mine
From the inception of the Hazelwood mine to the end of June 2013, approximately 609 hectares of land (including worked out areas, overburden dumps and mine perimeter areas) had been rehabilitated, of which approximately 90 hectares was subsequently lost to the west field expansion.52
The areas of the Hazelwood mine that have been rehabilitated to date are illustrated in green in Figure 3.13.
Figure 3.13 Progressive rehabilitation at the Hazelwood mine as at May 201453
Since privatisation of the mine in 1996/1997, 431.3 hectares of the mine have been rehabilitated, however Mr Faithful informed the Board that this figure does not paint the full picture.54
According to Mr Faithful, the majority of the rehabilitation works carried out at the mine prior to privatisation were ‘easy wins’, for example, external waste dumps, where all that was required was grading the overburden material (which was already relatively flat), and topsoiling and revegetating the area.55 Prior to privatisation, no rehabilitation works were undertaken within the pit or on any of the worked out areas of the Hazelwood mine.56
This was confirmed by Mr Robert Gaulton, former Mine Geologist with the SECV who worked at each of the Latrobe Valley mines between 1972 and 1996, and by Mr Graeme Freshwater, the former Mine Manager at the Hazelwood mine employed by the SECV.57
Some of the more recent rehabilitation projects undertaken by GDF Suez have been more difficult and labour and time intensive, as they have involved worked out areas and have therefore required re-profiling of batters and the removal of infrastructure. For example, between 2008 and 2012, the eastern end of the northern batters (being the part of the Hazelwood mine closest to the Morwell township) was rehabilitated.58 Significantly, the Hazelwood mine fire in 2014 did not impact this area.
Figure 3.14 illustrates the extent of rehabilitation undertaken at the Hazelwood mine against its progressive rehabilitation targets under the work plan in effect from time to time.
Figure 3.14 Progressive rehabilitation against work plan targets from 1992–201359
There was a difference in interpretation between GDF Suez and the Mining Regulator regarding whether the progressive rehabilitation proposed in the 2009 work plan needed to be commenced or completed by the end of mining each relevant block.60 For example, in the case of block 1C, GDF Suez understood that progressive rehabilitation had to be commenced by the end of that mining sequence in 2019, whereas the Mining Regulator’s view was that the planned progressive rehabilitation had to be completed by that date. This is a matter that both parties are willing to discuss.61
As outlined above, a number of preparatory steps, such as stability assessments and removal of infrastructure need to be carried out before overburden can be utilised. The whole process might take 4–5 years and accordingly, in order to complete the first planned stage of rehabilitation by 2019, stability assessments will need to commence very shortly.62
Although preparatory work for the end of the block 1C rehabilitation project has not yet commenced,63 GDF Suez is still identifying and carrying out smaller rehabilitation projects, with approximately 20 hectares rehabilitated since the 2009 work plan was approved.64 Shortly prior to the Hazelwood mine fire, a further nine hectares in the northern and eastern batters of the mine had been identified as potentially suitable for rehabilitation works in 2014. This area will be rehabilitated at the end of 2014.65
Adequacy of rehabilitation bond
The Board received several submissions querying the adequacy of the rehabilitation bond for the Hazelwood mine required under s. 80 of the Mineral Resources Act.66
The licensee paid a rehabilitation bond of $15 million by way of bank guarantee in May 1996, and this amount was reaffirmed on 8 June 2001.67 No witness was able to explain to the Board the precise methodology applied to determine the amount of the bond in 1996.68 It appears from pre-privatisation documents located by the Mining Regulator that the rehabilitation bond was set at $15 million as an ‘interim figure’ based on ‘an estimate of rehabilitation costs for ongoing progressive rehabilitation and final rehabilitation at present day values.’69 As at December 1995, the total rehabilitation liability was estimated to be around $20 million.70
Environment Victoria submitted that $15 million was demonstrably inadequate to cover the costs of rehabilitation of the Hazelwood mine.71 According to Mr George Graham, GDF Suez Asset Manager, the costs to complete rehabilitation would be less than $100 million, or about ‘$80-something million’.72 Ms White agreed that $15 million appeared to be an underestimate, particularly in light of the expansion of the Hazelwood mine, and that it was time for a reassessment.73
Section 79A of the Mineral Resources Act allows the amount of a rehabilitation bond to be reassessed. In 2010, the Mining Regulator commenced a project to devise a methodology to assess the rehabilitation liability for all mines in Victoria, but this stalled and was only recently re-enlivened.74 The Victorian Government suggested that this project might result in the rehabilitation bond for the Hazelwood mine being increased.75
Significantly, the amount of the bond was not re-assessed in 2001 or in 2009 when the land subject to the mining licence was substantially increased with the result that more land would be disturbed and require rehabilitation.76
Whilst there is considerable disparity between the current rehabilitation bond and the likely future rehabilitation liability, there are a number of other considerations raised by the parties that might influence the assessment of the bond amount. These include how future costs are tied to the approved progressive rehabilitation plan,77 the overall ‘risk profile’ of the licensee78 and its record of compliance, and the need to provide an incentive for the licensee to meet its rehabilitation obligations.79 Examination of the most appropriate balance between these competing factors goes well beyond the Board’s Terms of Reference but may be considered as part of the Mining Regulator’s review of its methodology for setting rehabilitation bonds.
FIRE MANAGEMENT POLICIES AND PROCEDURES
GDF Suez maintains a number of fire management policies and procedures, including the following:
- Emergency Response Plan – Hazelwood Mine (revised May 2013)
- Mine Fire Service Policy and Code of Practice (revised July 2013)
- Hazelwood Mine Fire Instructions (issued 27 July 2011)
- Internal Grass Slashing – Specification for Grass Mowing (issued 17 October 2011)
- Hazelwood Mine Guidelines for Season and Period Specific Fire Preparedness and Mitigation Planning (issued 13 September 2007)
- Check List for Fire Fighting Equipment Annual Inspection (issued 18 January 2013)
- Check List for Season Specific Fire Preparedness and Mitigation Planning (issued 24 November 2008)
- Check List for Hazelwood Slot Bunker Fire Services Wash Down and Routine Inspection
(issued 18 January 2013)
- Mine Fireman Assessment (issued 24 February 2012)
- Fire Person Duties Training Manual (issued 23 August 2012)
- GDF Suez Hazelwood Electricity Safety – Bushfire Mitigation Plan (for the period
commencing 1 July 2013).80
The Mine Fire Service Policy and Code of Practice is the central document concerning fire management strategies at the Hazelwood mine and is referred to in the work plan. This document is explored in further detail below under the heading ‘Mine Fire Service Policy and Code of Practice (revised July 2013)’.
While the ‘Hazelwood Mine Guidelines for Season and Period Specific Fire Preparedness and Mitigation Planning’ primarily address preparedness to respond to the outbreak of fire, they also refer to a number of matters that are relevant to the issue of fire prevention.81 The Guidelines note that ‘wetting down exposed coal levels will assist in dust suppression.’ This is important because:
With the right conditions brown coal, once loosed and mixed with air, will readily spontaneously combust, while brown coal still undug is in the safest fire resistance condition. While the local conditions within the Morwell brown coal mine may and will often be very different to that of the surrounding areas, the mine conditions will usually be more severe than the surrounding areas; this is due to the lack of grassland, promoting rapid run off of rainfall, and the depth of the mine promoting its our [sic] unique environment. Consequently, the brown coal levels will usually dry out quicker than the surrounding grassland fields, promoting a problem with air borne coal dust, and the greater need for dust suppression.82
The Guidelines also recognise the risk of flying embers entering the mine:
6.7 FLYING EMBERS
Flying embers from wildfire in remote grasslands and forests can travel for kilometres and contain sufficient energy to start spot fires when they land on combustible materials. During times when bushfires are in the immediate area, a heightened awareness is required to detect the landing of these fire initiation sources and hence to take immediate action to report and put these spot fires out.83
Other policies and procedures relating to preparedness to respond to fire are discussed in Chapter 2.2 Preparing for fire.
Mr Steven Harkins, GDF Suez Director of People, Culture and Environment, explained that each year GDF Suez declares the commencement of a fire season, sometimes as early as November, depending on how wet or dry the winter period has been.84
In the lead up to the commencement, or during the early stages of the declared fire season, a range of preparedness measures are undertaken at the Hazelwood mine, including grass slashing and other fuel reduction measures.85
Mr Robert Dugan, GDF Suez Mine Production Manager, stated that each year GDF Suez conducts a grass slashing program, comprising approximately 530 hectares between the mine boundary and the top of the open cut, which is usually completed by December or January.86 Mr Dugan explained that he conducts a review in about February of each year to determine whether the grasslands require any further slashing.87
GDF Suez has documented the requirement to conduct grass slashing in the Mine Fire Service Policy and Code of Practice. Section 7.9 specifies that by the beginning of the declared fire season, an up-to-date drawing of the ‘Fire Prevention, Slashing, Grazing Layout Plan’ should be issued. Grass cutting must then be carried out in accordance with the Plan, with the actual start and finish dates for grass cutting dependent on weather conditions.88
The GDF Suez ‘Internal Grass Slashing – Specification for Grass Mowing’ procedure prescribes the equipment and method to be used when undertaking grass slashing works.
GDF Suez produced a ‘scope of works’ document for grass slashing to be carried out for the 2013/2014 fire season.89 Under the scope of works, slashing, mulching and mowing were to be carried out in two stages:
- Stage 1: initial slash from November to December 2013, to be completed by 31 December 2013.
- Stage 2: follow up slash of regrowth if required, to be completed by mid-February 2014.90
Upon completion, all grass, weeds and undergrowth were required to be no greater than 75 millimetres in height.91
According to the Slashing, Mulch & Mowing Layout Plan, these works covered areas outside of the perimeter of the open cut, and not the mine floor or batters.92
In the 2013/2014 fire season, grass slashing was completed by the first week of January 2014.93 On around 3 February 2014, Mr Dugan prepared a weekly status report on preparedness measures at the Hazelwood mine, which noted that grass slashing was complete, but follow up slashing might be required in late February 2014.94
During the Hazelwood mine fire, Mr Kevin Hayes, Field Subject Matter Expert and Workplace Inspector, Earth Resources Unit at VWA, visited the Hazelwood mine on a number of occasions.95 Toward the end of the mine fire, on 20 March 2014, Mr Hayes observed that grass in excess of 100 millimetres in height and trees and shrubs had been allowed to grow within the 50 metre fire break zone around the perimeter of the mine. Mr Hayes issued an improvement notice to GDF Suez under the Occupational Health and Safety Act 2004 (Vic) (OHS Act), which required GDF Suez, by 23 June 2014, to maintain the fire break corridor, to review the adequacy of the 50 metre wide fire break, and to review the requirement to regularly monitor its maintenance particularly during the fire season.96
Throughout the declared fire season, GDF Suez adopts a range of other measures to reduce the risk of fire at the Hazelwood mine, including:
- the issuing of fire preparedness plans and alerts on high risk days
- wetting down of coal faces in the operating areas of the mine
- washing down vehicles entering the mine
- having water tankers available and kept at least half full.97
The practice of wetting down coal faces is documented in the Hazelwood Mine Fire Instructions issued 27 July 2011.98 This policy document primarily deals with preparedness and response measures in the event of a fire and is discussed in more detail in Chapter 2.2 Preparing for fire.
The Instructions also refer to some procedures aimed at the prevention of fire. Under the Instructions, the Director of Mining, the Production Manager, or the Mine Production Superintendent declares a ‘Fire Alert’ when hot, dry or windy conditions are expected and there is a high risk of fire rapidly spreading in the mine.99 When a ‘Fire Alert’ has been declared:
[A] Shift Operations staff member shall continuously man the Control Centre Office. The 1×7 [crew] shall ensure that cable protection sprays are turned on for initial wetting down and that wetting down is carried out on coal surfaces, conveyors and transfer points to provide Fire protection and to check the spread of any Fire.100
This practice is limited to operational parts of the Hazelwood mine.
In addition, s. 4 of the Hazelwood Mine Fire Instructions sets out a number of other preventative measures that apply at all times, including:
- Smoking and carrying of cigarettes is prohibited in most areas of the Hazelwood mine.
- Welding, burning, cutting, grinding and use of open flame appliances and portable engines
are strictly regulated and require permits.
- Strict procedures apply to the use, maintenance and cleaning of operational plant and equipment such as conveyors, machines and the Hazelwood Slot Bunker.
- Motor vehicles are not permitted to travel across coal faces without an approved exhaust system, and dozers and other vehicles are subject to a range of other requirements.101
Mine Fire Service Policy and Code of Practice (revised July 2013)
The Mine Fire Service Policy and Code of Practice includes a statement that encapsulates GDF Suez’s understanding of the risk of fire at the Hazelwood mine:
Hazelwood Mine has suffered a number of fires over the years. Many of these have emanated from external “Bush Fires”. Following a major fire in 1944 the Stretton Royal Commission made a number of significant recommendations relating to external forests and to internal water supply and sprays, which are still a major part of the Hazelwood Mine Fire Prevention Policy. However, fires have also been started from within the mine due to plant malfunctions. Notable amongst these have been fires on Dredgers and belt fires damaging belt, head ends and the rising conveyors. Fires have also been caused by vehicles and mobile plant due to coal deposited on hot exhausts igniting and dropping off to start a fire. Although many fires have started from outside, no fire has escaped the Hazelwood Mine and entered the external environment.
Due to the methods employed for the extraction and use of Brown Coal in the Hazelwood Mine operations, large areas of brown coal are generally exposed in the operating faces, permanent batters and floor of the mine. Whilst the brown coal in its raw state is a high moisture fuel and difficult to burn, it weathers, dries and readily degrades to a fine dust which ignites easily under the right conditions, and can spontaneously ignite.
Potential sources of ignition are frequently present in the form of electrical faults, faulty mechanical equipment, vehicle exhausts, metal cutting and welding activities, etc. A fire within the Hazelwood Mine can put all nearby machinery and equipment at risk particularly if coal spill or dust accumulates. In the mine, fire danger to personnel is not great provided that they are not trapped by machinery, buildings, or coal batters and provided that refuge is available from both heat and smoke. Although the effects of carbon monoxide need to be monitored in a large scale brown coal fire.
Brown coal fires are best suppressed by the application of water. Wetting of the coal lays the coal dust, and helps to extinguish the fire and prevent it from spreading. Large quantities of water are required to extinguish deep seated burning, and often when burning coal is wetted, sufficient heat remains to dry out the surface again and to allow the fire to re-establish. Sometimes, it is best to dig out the batter where a fire is smouldering to completely remove any remnants of it.102
The Policy describes its purpose as follows:
This Fire Service Policy and Code of Practice is based on the adoption of sensible precautions as well as the establishment of a system of fire protection in the Hazelwood Mine to:
(a) protect all personnel within the open cut,
(b) protect all plant and equipment required for the maintenance of coal winning operations, and
(c) protect the brown coal reserves to enable continuation of coal winning activities.
The aim is to prevent or extinguish any fire which may threaten the brown coal winning activities, and to restore normal operating conditions as early as possible after a fire. Training of all personnel in the fire fighting methods and procedures is an integral part of preparedness for combating fires.103
A number of mine procedures address prevention of fire, some of which have been discussed in relation to other policy documents above. In addition, the Mine Fire Service Policy and Code of Practice requires that a fire-break and control of grassed and forested areas be maintained within the ‘zone of responsibility’. The zone of responsibility is defined as the area within the perimeter of the Hazelwood mine, plus those areas within the following distances of the operational area: northern side – one kilometre; western side – one kilometre; southern side – 0.5 kilometres; and eastern side – one kilometre.104 The fire-break must meet the following requirements detailed in Figure 3.15.
Figure 3.15 Fire-break requirements under the Mine Fire Service Policy and Code of Practice105
|Within 50 metres
of the perimeter of
the Hazelwood mine
|A continuous and permanent fire-break corridor which is constantly monitored and in which:
|From the outer edge of the 50 metre fire-break zone to the Hazelwood mine boundaries (in all directions) including all road verges||During the proclaimed fire season:
|Within the zone
|Vegetation should primarily consist of:
Under the Policy, the actively mined areas of the Hazelwood mine are to be protected by wetted corridors established along the working levels. Pipelines and sprays are to be provided such that if all sprays on working levels were to operate simultaneously under light wind conditions:
- A minimum of 50 per cent of exposed coal on working levels would be wetted at a rate of at least six millimetres of water depth per hour.
- The wetting down would be such as to provide intersecting corridors of wetted coal. The width of the wetted corridors should be a minimum of 50 metres. The unwetted coal areas should not exceed 12,500 square metres in area with a maximum dimension in any direction of 250 metres. Portable or readily relocatable sprays are to be used if necessary to achieve this requirement.106
The public hearings focussed on s. 3.4 of the Policy, which specifically addresses the ‘worked out batters’ of the Hazelwood mine:
As a minimum requirement worked out batters are to be protected as follows:
- All benches are to be clay covered.
- All berms are to be eliminated by trimming or by filling with clay such as to shed fretted coal provided that batter stability calculations indicate that neither of these options will cause batter failure.
- Tanker filling points are to be provided such that a tanker on any part of the worked out batters is within 5 minutes travel of a tanker filling point.
NOTE: in the absence of tanker filling points a hydrant manifold will suffice. Fixed sprays should be used in conjunction with the droppers for the tanker filling points in order to provide wetted breaks.
- Where possible access to areas worked out to be maintained.
- Where practicable, fire break zones extending down to full depth of each batter may be utilised such that the length of exposed coal in any one batter is not greater than 500 m. These zones can be in the form of metalled vehicle access ramps or clay covering, a minimum of 8 m wide.107
The ‘worked out batters’ are considered to be those batters which are not in areas ‘where excavation or transport plant operate, including working and transport levels, reserve coal areas, regular travel routes for dredgers and slew conveyors, and service corridors for essential operational services.’108
The Policy notes that the design and location of tanker filling points should involve consideration of ‘ease of access, location and reliability of the water supply’.109
Water supply limitations are recognised by the Mine Fire Service Policy and Code of Practice, which provides that:
In order to properly protect all parts of the Hazelwood Mine, pipe work and sprays are to be installed as laid down by this Fire Service Policy and Code of Practice. However, it must be understood that a larger water supply system would be required to run all the sprays and protection systems simultaneously. This policy provides for diversity in the simultaneous application of the fire protection water supplies and distribution.
The maximum demand as defined in this Fire Service Policy and Code of Practice is an allowance of water usage upon which the design of the water supply system is based. The maximum demand rate of water use is considered to be sufficient to meet any likely contingency within the Hazelwood Mine. The distribution of this allowance of water usage is reasonably flexible for any situation but the use of more water than allowed for in one area may cause a reduction in the performance of the system.110
Section 7.1.1 of the Policy specifies the source of water supply must be designed so that supply is from at least two systems, such that the loss of the larger system or pumping station will not reduce the supply available below 50 per cent of the designed maximum demand.111
Section 7.1.2 of the Policy specifies that the system must be able to supply sufficient water to operate whichever is the greater of either Option A or B described below:
Option A – Consisting of the sum of the following:
- An allowance to operate rotary sprays to provide cover to 50 per cent of exposed coal and all machine and conveyor protection sprays on the working levels.
- An allowance to operate three hydrants on one header on each of the working levels.
- An allowance to operate the rotary sprays protecting one quarter of the length of the trunk conveyor system below grass level.
Option B – Consisting of the sum of the following:
- An allowance to operate rotary sprays to provide cover to 25 per cent of exposed coal and all of the machine protection sprays on the working levels.
- An allowance to operate three hydrants on one header on each of the working level [sic].
- An allowance to operate the rotary sprays protecting one half of the length of the trunk conveyor system.
- An allowance to operate three hydrants per header for the headers protecting half of the length of the trunk conveyor system.112
Evolution of Mine Fire Service Policy
The Mine Fire Service Policy and Code of Practice evolved from the Latrobe Valley Open Cut Mines – Fire Service Policy, which was produced by Generation Victoria prior to privatisation in 1994 (1994 Policy and Code).113
The 1994 Policy and Code replaced the Latrobe Valley Open Cuts Fire Protection Policy (Revision 1), dated November 1984, produced by the SECV (the predecessor to Generation Victoria) (1984 Policy and Code). The 1984 Policy and Code in turn was a revision of the SECV’s Latrobe Valley Open Cuts Fire Protection Policy, dated December 1981 (1981 Policy and Code), which was developed following the review of the 1977 fire at the Hazelwood mine.114
Mr William Brown, former Fire Services Officer at the Hazelwood mine, told the Board that the 1994 Policy and Code and the predecessor versions developed by the SECV were the ‘bible’ for fire services at open cut brown coal mines in the Latrobe Valley.115
The 1994 Policy and Code was signed off by the mine managers of all three open cut brown coal mines in the Latrobe Valley (Yallourn, Loy Yang and Hazelwood), and applied to all three mines.116 The policy contained requirements and operating procedures for fire protection services relevant to these open cut coal mines and their surrounding areas.117 The 1994 Policy and Code states that it ‘evolved over many years of open cut operation and draws on the experience gained from general fire service operation and from several major open cut fires,’ including the 1944 fire at the Yallourn mine and the 1977 fire at the Hazelwood mine.118
Section 1.1.4 of the 1984 Policy and Code dealt with fire prevention measures specifically directed to the worked out areas of all three Latrobe Valley mines:
1.1.4. Worked Out Batters (refer to fig 1.2)
As a minimum requirement worked out batters are to be protected as follows:
- All benches are to be clay covered.
- All berms are to be eliminated by trimming or by filling with clay such as to shed fretted coal provided that batter stability calculations indicate that neither of these options will cause batter failure.
- Fire break zones extending down to full depth of each batter may be utilised such that the length of exposed coal in any one batter is not greater than 500 m. These zones can be in the form of metalled vehicle access ramps, a minimum of 8 m wide or in the form of a 20 m width clay covering.
Alternatively fixed spray breaks may be used, but it should be noted that water for these sprays has not been included under the maximum demand conditions, and this protection should not be considered as reliable as clay fire breaks or vehicle access ramps.
Figure 2 shows an example of this protection.119
That is, the 1984 Policy and Code provided that, as a minimum, exposed coal in the worked out batters must be protected by either (a) the use of fire-break zones in the form of 20 metre wide clay covering or eight metre wide vehicle access ramps; or (b) fixed sprays.
Figure 2 of the 1984 Policy and Code is reproduced in Figure 3.16.
Figure 3.16 Worked out batters – example of fire protection (Figure 2 of the 1984 Policy and Code)120
Section 1.1.4 of the 1984 Policy and Code resulted from a recommendation made by the Review Committee inquiring into the fire at the Hazelwood mine on 4 to 6 November 1977. In its final report, the Review Committee recommended that the mine ‘establish and implement a specific policy for the clay covering of dormant batters and levels. In developing this policy, consideration should be given to operational feasibility and economics of batter redesign to facilitate the application of clay cover.’121
The Review Committee also noted that immediately following the 1977 fire ‘an accelerated programme of covering dormant levels and ramps within the [Hazelwood mine] was implemented and achieved during the summer period.’122 However, the cost of providing a stable clay covering in the worked out open cut area had been assessed at $8 million for clay excavation, transport and covering, plus additional costs of between $5 and $10 million for relocation of existing infrastructure (roads, power lines, drainage etc). As a potentially more economical alternative, the mine operator had begun to explore the feasibility of flattening existing coal batters to allow for a thinner stable clay covering layer.123
The equivalent to s. 1.1.4 of the 1984 Policy and Code is found in s. 4.4 of the 1994 Policy and Code, which introduced an alternative measure:
As a minimum requirement worked out batters are to be protected as follows:
- All benches are to be clay covered.
- All berms are to be eliminated by trimming or by filling with clay such as to shed fretted coal provided that batter stability calculations indicate that neither of these options will cause batter failure.
- Tanker filling points are to be provided such that a tanker on any part of the worked out batters is within 5 minutes travel of a tanker filling point. Fixed sprays should be used in conjunction with the droppers for the tanker filling points in order to provide wetted breaks.
- Where practicable, fire break zones extending down to full depth of each batter may be utilised such that the length of exposed coal in any one batter is not greater than 500 m. These zones can be in the form of metalled vehicle access ramps or clay covering, a minimum of 8 m wide.124
In the lead up to privatisation of the Hazelwood mine, the 1994 Policy and Code was replaced by the Hazelwood Power Corporation Fire Service Policy and Code of Practice dated 8 November 1995. Mr Brown provided Revision 1 of this document, dated 4 December 1995, to the Board.125 The equivalent provision was essentially the same in this version of the policy, except that a note was added that in the absence of tanker filling points, a hydrant manifold would suffice.126
Section 3.4 of GDF Suez’s 2013 Mine Fire Service Policy and Code of Practice is substantially identical to the equivalent provision in the 1995 document, and the requirement has not been revised since that time.127
Accordingly, the minimum requirements under both the 1994 Policy and Code and the current (2013) Mine Fire Service Policy and Code of Practice are:
- Either tanker filling points or hydrant manifolds are to be provided within five minutes travel of any part of the worked out areas.
- Fixed sprays should be used in conjunction with droppers for the tanker filling points in order to provide wetted breaks.
- The use of fire-break zones in the form of access ramps or clay covering is provided as an
alternative, rather than the primary means of prevention.
Mr Richard Polmear, GDF Suez Carbon Efficiency and Improvement General Manager, has been employed at the Hazelwood mine in a variety of roles since 1982, including roles in which he was responsible for fire services.128 Prior to that, Mr Polmear was employed at the Yallourn open cut mine from 1980.129 As submitted by GDF Suez, with over 30 years experience at the Hazelwood mine, Mr Polmear was uniquely placed to provide insight into why the changes occurred between the 1984 and 1994 Policies and Codes.130
Mr Polmear explained to the Board that at the time when the 1981 Policy and Code was drafted, mining at the Hazelwood mine was far less developed and ‘there were no worked out batters at the Hazelwood Mine, there was no Loy Yang Mine; the only mine that had worked out batters was the Yallourn Mine.’131
According to Mr Polmear, the Yallourn mine is far less deep and the batter profiles are generally much flatter than at the Hazelwood mine.132 Because the Hazelwood mine is deeper and the batter profile steeper, particularly in the northern batters, the use of clay covering as a fire break was not practicable in all parts of the mine at Hazelwood:
… the proposal as proposed in [s. 1.1.4 of the 1984 Policy and Code], which worked in concept at Yallourn, doesn’t work physically at Hazelwood because the overall slope is 3:1… [installing fire-breaks] would mean it would be one continuous slope from top to bottom, which means you’ve lost all access, you’ve lost any possible corridors for easements and the like. So the only way that you can cure that…[is] you actually have to go back further at the top to flatten it so that you’ve got access on benches. If you do that, then you actually have problems with the services that run at the top of those, so at that critical point just round the corner from where we’ve done rehab, it steepens up from about 6:1 to 3:1 overall slope. If you apply this rule at 500 metre intervals and you put the dirt in, then you end up with paddocks, but paddocks which are now inaccessible from top to bottom. So, if a fire does get in there, you can’t get in to fight it.133
Mr Polmear considered that, for practical purposes, whilst the 1984 Policy and Code was in effect, the alternative of fixed spray breaks was the only option capable of being implemented at the Hazelwood mine.134
However, according to Mr Polmear, water supply was also a practical issue that complicated fire protection at the Hazelwood mine:
The characteristics of the Mine created particular challenges as regards fire protection. It is much deeper than the Yallourn mine, with the result that the supply of water through reticulated fire service pipes is much more complex, as safe operation requires pressures to be maintained between 40 m and 115 m head on each level for static and maximum demand. At the Mine this requires 3 different pressure zones that could not be safely interconnected.135
Removal of pipework forming part of the fire service network
The serviceability of fire service pipes in the northern batters at the Hazelwood mine became a significant issue in the early 1990s. Mr Polmear explained that pipes in the northern batters were installed between 1955 and 1980 and were some of the oldest at the mine.136 The pipes installed throughout this period also had little or no internal or external corrosion protection and because of the acidic nature of coal, they were particularly susceptible to degradation.137
By 1990, corroded and failing pipes in the oldest areas of the Hazelwood mine, particularly around the northern batters, had become a significant problem because leaking water could enter the batter and cause batter movement and potential instability. Mr Polmear recalled one instance where a leaking pipe resulted in a two metre vertical movement in a batter.138
Repairing pipework required welding and was also problematic, as this process in itself creates a fire risk and in fact resulted in a number of fires in the worked out areas of the Hazelwood mine.139
Mr Polmear explained that in 1992, in light of the problems with ageing pipework, the SECV commissioned independent consultants, Richard Oliver International Ltd, to conduct a risk assessment for the purpose of seeking an exemption from complying with the requirements of ss. 1.1.4 and 1.1.5 of the 1984 Policy and Code in respect of the worked out areas, including the north-eastern and eastern batters, of the Hazelwood mine.140
In June 1992, Richard Oliver International Ltd produced a report titled ‘Fire Risk Analysis of the Worked Out Areas of Morwell Open Cut’, which concluded that:
Exemption from ss.1.1.4 and 1.1.5 would increase fire risk in the worked out areas and would increase SECV and [Hazelwood mine] liability in this regard. Presently this risk is not minimal. An exemption is thus not appropriate.
Moreover any such policy exemption or modification should not proceed until there has been a demonstrable reduction in fire risk.141
The report made a number of further observations relevant to this Inquiry:
- As at 1992, around eight per cent of the total plan area of the worked out areas of the Hazelwood mine consisted of exposed coal, that is, areas not covered by either clay covering or sprays.142
- As at 1992, the water supply to the worked out areas appeared satisfactory, but ‘could be a little greater (perhaps 20 per cent more) than policy requirement for the worked-out areas and batters’ to cover remaining exposed coal.143
- ‘With all but 8 per cent of the plan area of the worked-out areas and batters covered by water or clay, significant spread of fire through the worked-out areas does not appear to be a key threat.’144
- As a result, the policy (as it then was) addressed the risk of fire spreading in the worked out areas, but spread of fire may result from (among other things) ‘embers or coal or foliage fires blown by the wind.’145
- From November 1989 to April 1992, there were 28 fires reported in the worked out areas. In these prior incidents, piped water was the major means of fire suppression.146 This was a reference to the reticulated water system in the northern batters.147
- Risk to the safety of personnel arising from a fire in the worked out areas was identified as minimal and a loss of life ‘would not be anticipated.’148
- However, ‘corporate image’ and ‘other community impact outside the mine’ were identified as potential consequences of any fire in the worked out areas of the Hazelwood mine.149
The report recommended that the SECV carry out a detailed engineering survey of the reticulated fire services water system, including an assessment of the northeast corner coal production area, and that this survey should cover maintenance, design and pump aspects.150 In terms of potential revisions to the 1984 Policy and Code, the report suggested that the number, distance and capacity requirements for tanker filling points should be specified.151
Despite the results of the 1992 risk analysis, s. 1.1.4 was revised in the 1994 Policy and Code such that clay or fixed spray breaks were no longer a minimum fire protection requirement so long as tanker filling points were provided within five minutes travel of any part of the worked out areas.
Following this revision to the Policy and Code, until around 2007, any degraded or leaking pipework was progressively removed from the northern batters,152 principally in the area that was affected by the Hazelwood mine fire in 2014.153 The fire service network as it existed immediately prior to the Hazelwood mine fire is shown in Figure 3.17.
Figure 3.17 Fire service network as at 9 February 2014154
Pipework was only ever removed from the northern batters as a result of it becoming unserviceable, with the exception of pipework removal due to the:
- development of the internal overburden dump (during the period 1998–2003)
- construction of the Hazelwood Ash Retention Embankment (which followed the creation
of the internal overburden dump).
- completion of rehabilitation works in 2007/2008.155
When Mr Polmear was asked why these pipes were not replaced once they had been removed, his answer was ‘they didn’t need to be, in accordance with the policy.’156
During the Hazelwood mine fire, extensive pipework was installed in the worked out areas of the Hazelwood mine in order to assist with the fire suppression effort. This is detailed in Chapter 2.3 Fighting the Hazelwood mine fire.
Mr Polmear confirmed that the pipework removed during the period 1994 to 2007 corresponded with the area of the northern batters where pipework was installed during the Hazelwood mine fire.157 After 1992, no risk assessment was conducted to determine whether any removed pipework should be replaced.158
During the Inquiry’s public hearings, there was debate as to whether GDF Suez was entitled to depart from the fire service network depicted in the 1996 work plan without the Mining Regulator approving a variation of the work plan. In his expert opinion to the Board, Mr Roderic Incoll, Bushfire Risk Consultant, suggested that alterations to the fire service network were unauthorised and ought to have attracted the attention of the Mining Regulator.159 Ms White also initially gave evidence that such a modification would require a variation to the work plan.160
GDF Suez submitted that the 1996 work plan merely referred to the existence of the fire service network and the inclusion of a diagram of that network did not constitute a fixed requirement without which the commitment to the overall policy was breached.161 GDF Suez claimed, in effect, that the operative requirement under both the 1996 work plan and 2009 work plan variation adhered to the 1994 Policy and Code, and having regard to the flexible fire protection options provided under that policy, it would be illogical and unreasonable to ‘set in stone’ the fire service network as it existed in 1996.162
Ms White ultimately agreed with GDF Suez’s proposition that as long as the standards in the 1994 Policy and Code continued to be met, that would constitute compliance with the requirements of clause 7.7 of the approved work plan.163
Preventing fire in the worked out areas of the Hazelwood mine
Mr Incoll explained to the Board that:
Fire is an ever-present hazard and enemy of production that can arise from many causes internally and at times can arise unseen from outside the Mine… One way this can occur is by the ignition of exposed coal in the Mine by fires burning in the rural landscape, either by direct flame attack or ignition by wind-bone [sic] burning embers.164
GDF Suez’s main strategy for preventing the outbreak of a mine fire as a result of an external fire has been vegetation management in the rural land surrounding the Hazelwood mine, by grass slashing, grazing, and fire-breaks.165
While vegetation management can be an effective strategy against a direct firefront, it does not address the risk of mass ember attack into the Hazelwood mine from external sources resulting in widespread simultaneous ignitions (the likely cause of the Hazelwood mine fire in 2014).166 The key issue for resolution, therefore, is ‘[t]he protection of exposed coal that ignites easily on hot, dry windy days.’167 Given the scale of mining at the Hazelwood mine, the extent of the area of exposed coal to be protected is a major factor in the challenge of protecting the mine from fire.168
According to Mr Incoll, ‘[e]ffective fire protection of a mine of this size from ignition by flames or embers from outside the mine can only be achieved by either covering exposed coal with earth and/or a water spray to wet down coal faces.’169 Mr Faithful agreed.170 Independent expert, Professor David Cliff, Professor of Occupational Health and Safety in the Minerals Industry and Director, Minerals Industry Safety and Health Centre at the University of Queensland, put it to the Board that: ‘fundamentally, if the coal can’t be exposed to air, it can’t burn; it’s as simple as that.’171
From this perspective, Mr Incoll considered that the fire prevention measures contained in the Mine Fire Service Policy and Code of Practice and related policies were inadequate to protect against the risk of fire in the worked out areas of the Hazelwood mine.
Mr Incoll reported to the Board that under the Mine Fire Service Policy and Code of Practice the strict rules regarding vegetation that govern the fire break zone surrounding the perimeter of the Hazelwood mine do not apply to worked out areas within the Hazelwood mine. Vegetation of the nature and density observed by Mr Incoll in May 2014 within areas of the mine obstructs access for firefighting, makes it difficult to suppress embers with water sprays and if ignited under hot dry windy conditions may become a scrub fire.172 Mr Incoll recommended that it be addressed.
Mr Incoll also reported to the Board that the water supply for the fire service network is inadequate and there are no water coverage requirements specified for the use of fixed spray breaks in worked out areas. The effective cover of exposed coal surfaces with water sprays requires a reticulation system capable of delivering water in the volumes required for dampening down exposed coal in all sectors of the mine.173
Further, the use of fire-break zones on worked out batters was not implemented and exposed batter lengths exceeded 500 metres. Even if fire-breaks were effective in containing fire to a 500 metre section of the mine, this would represent an extensive firefront to deal with under hot dry windy conditions.174
Mr Incoll told the Board that the minimum requirements under s. 3.4 of the Mine Fire Service Policy and Code of Practice:
…may well be adequate, I think they’re intended for internal protection of the mine where you have limited fire and not under total fire ban weather conditions, but they’re not when you’re looking at widespread fires started by an ember shower. It’s my firm conviction, as I’ve said, it has to be either covered with some sort of a blanket of earth or another substance or covered by water to resist that type of attack.175
Mr Incoll concluded:
In my opinion considering the outcome of the recent fire, anything less than 100 per cent spray coverage availability during hot dry windy conditions, or full earth covering of the Northern Batters is inviting a recurrence of the incident with similar outcomes. For this reason this situation must be permanently remedied.176
In his initial written submission, Mr Incoll recalled that ‘[t]he standard response of the open cut fire services under the [SECV] arrangements on hot dry windy days at any time of the year, was to start up large scale irrigation systems that covered exposed coal faces with a water spray.’177 During the public hearings, Mr Incoll confirmed that he had personally witnessed this happen.178
Mr Freshwater told the Board:
For fire safety, pipelines and sprinklers were installed to the whole of the mine, including the worked out areas. The sprinklers produced a rotating fine mist of water… On days when it was hot or a fire danger day, the fire service personnel would arrive at work very early and turn on the sprinklers which would wet down the coal levels and batters.179
Mr Freshwater also noted that fire service personnel used to ensure that all vegetation in the mine was removed.180
GDF Suez submitted that observations regarding the current adequacy of water supply were based on a misapprehension of the coverage of the fire service network during the ‘good old days’ of the SECV.181 As noted above, neither the current Mine Fire Service Policy and Code of Practice nor the 1994 Policy and Code required 100 per cent coverage for operational areas of the Hazelwood mine and explicitly stated the system was incapable of such coverage.
When this was put to Mr Incoll, he accepted that this was what the policy said, but his impression at the time was that in fact, the fire service network could produce 100 per cent coverage.182 Furthermore, Mr Incoll confirmed that as a preventative measure it was possible to manage the water supply so that, over the course of a morning, areas that need to be wetted down could be wetted down sequentially and that is what had occurred in the past.183
Mr Incoll identified rehabilitation as a routine method of covering exposed coal that could be used as a fire prevention method.184 The value of rehabilitation as a fire prevention measure was also known both to GDF Suez185 and the Mining Regulator.186
However, Mr Faithful outlined a number of obstacles (see under the heading ‘Approved rehabilitation plan for the Hazelwood mine’ above) that make progressive rehabilitation a complex, costly and time-consuming exercise. The practical limitations of rehabilitation as a fire prevention measure were also recognised by Mr Leonard Neist, Executive Director, Health and Safety, VWA,187 Ms White,188 Professor Cliff,189 Mr Gaulton190 and Mr Freshwater.191
According to Mr Faithful, it would be considerably more costly to accelerate rehabilitation of the northern batters from the existing 2009 rehabilitation plan and any attempt to do so would be constrained by consultation and agreement with a range of third parties.192 The additional cost of accelerating progressive rehabilitation is primarily due to the need to remove infrastructure earlier than anticipated and difficulties with sourcing suitable overburden material outside of the planned mining sequence.193
Environment Victoria submitted that none of the factors identified by Mr Faithful necessarily precludes accelerated progressive rehabilitation of the worked out areas of the Hazelwood mine,194 suggesting:
- The steps identified by Mr Faithful as being required for rehabilitation would be required no matter when rehabilitation occurred.195
- The particular steps required for rehabilitation were not impediments in the sense that GDF Suez would lack the capability to undertake them, or that they would preclude progressive rehabilitation occurring.196
- Mr Faithful recognised the possibility of importing overburden from different parts of the mine, sourcing it specifically for rehabilitation rather than relying on coal mining by-product, or sourcing it externally.197
- GDF Suez had not provided any evidence of any investigations it had made about sourcing overburden from other parts of the mine, sourcing it from the over burden dump or sourcing it externally.
A number of witnesses canvassed the potential of capping exposed coal with clay or some other fire retardant substance as an alternative fire protection method to complete rehabilitation.
Mr Gaulton raised the possibility of coating exposed coal with ‘a fire protectant such as stabilised clay and cement mixture’, such as ‘shotcrete’ that could ‘provide and [sic] interim fire prevention measure until the batters can be fully rehabilitated.’198
Professor Cliff described permanent rehabilitation as the ‘ultimate solution’ but suggested temporary capping was commonly used in the mining industry to treat stockpiles or waste heaps of coal that have the potential to spontaneously combust.199 Examples of treatments that might potentially be used include fly ash slurries, foams, gels, organic surfactant materials, polymers, bituminous tar, a form of clay, ‘shotcrete’, or some other form of cementation.200
GDF Suez submitted that there was no evidence that any of these measures had been trialled as a fire prevention measure in open cut brown coal mines anywhere in the world.201 As Mr Gaulton noted, this might be because the Latrobe Valley is unique in that ‘[t]his is the only place in the world where huge massively thick seams of brown coal are mined and exposed to the atmosphere with the intrinsic consequences of that.’202 Mr Gaulton told the Board that ‘shotcreting’ and other treatments had been used in potentially similar applications, for example, as a treatment applied to both underground and high batters of open cut mines to enhance stability.203 Such treatments have been used in open cut black coal mines in Queensland.204
GDF Suez identified other potential issues associated with capping exposed coal with clay or some kind of fire retardant treatment:
- If a treatment was applied to worked out batters without reshaping works having first been undertaken, this could impact on benches, roads, drains, bund walls and general access.205
- The impact of such works on horizontal bores in the northern batters would need to be carefully managed, so that de-watering was not disrupted, giving rise to stability issues.206
- Flattening batters could increase the risk of fire by increasing the surface area of exposed coal.207
- Applying a surface treatment could involve exposing workers to risks by having to work at heights.208
- It is an important element of batter stability management that batters be visible and readily accessible and a superficial coating to worked out batters could impede routine geotechnical inspections and the maintenance of batter stability.209
Based on some of the issues identified above, Environment Victoria preferred permanent rehabilitation to temporary capping.210 It also identified other factors that made rehabilitation superior to temporary capping and wetting down coal faces with sprays:
- Because full rehabilitation involves the ‘laying back’ of the batters, reducing their steepness, the batters are more accessible to firefighters.
- Having a less steep slope would mean stability issues would not need to be dealt with on an ongoing basis and visual inspection of batters would no longer be required.
- Once completed properly, rehabilitation is immune from human error and technological failure. Unlike water protection, there would be no reliance on decisions by people to activate a water protection system, nor does rehabilitation rely on technological aspects such as having access to electricity and pipes not failing.211
There was also evidence suggesting that not all of the obstacles identified by GDF Suez were insurmountable. For example, Professor Cliff told the Board that:
- Existing coal treatments had been successfully applied to vertical or near vertical coal faces.212
- Fly ash slurries can be easily applied to steep batters and at heights using equipment similar to that used by the CFA to apply foam during the Hazelwood mine fire.213
- Contrary to the suggestion that flatter batters might present a higher fire risk due to a greater surface area, steep vertical coal faces in fact present a greater fire risk due to the effect of convection updrafts.214
- Open cut coal mines in New South Wales and Queensland, commonly rely on methods other than visual inspection, such as ground-penetrating radar and other 3-dimensional scanning systems, to monitor batter stability. As such, this is not necessarily an obstacle to applying a fire retardant to exposed coal.215
Further, in Mr Gaulton’s opinion, the application of a surface treatment would not necessarily obstruct a horizontal drain, as the bore hole casing usually projected around a metre from the coal face.216
While the level of optimism surrounding the prospect of capping exposed coal varied considerably, there was a consensus that a risk assessment would need to be undertaken before any option or combination of options was adopted.217
OCCUPATIONAL HEALTH AND SAFETY
Occupational health and safety management system standards
The 2009 work plan variation states that GDF Suez is compliant with AS4801.218 AS4801 is an Australian and New Zealand Standard for occupational health and safety management systems (OHSMS). The Standard is designed as a framework primarily for independent external audits and reviews of an organisation’s OHSMS, but it can also be used as a framework for internal audits.219
The purpose of AS4801 is to specify:
requirements for an occupational health and safety management system (OHSMS), to enable an organisation to formulate a policy and objectives taking into account legislative requirements and information about hazards or risks. It applies to those hazards or risks over which the organisation may exert control and over which it can be expected to have an influence.220
The Standard may be used by any organisation that wishes to:
- implement, maintain and improve an OHSMS
- assure itself of its conformance with its stated OHS policy
- demonstrate such conformance to others
- seek certification/registration of its OHSMS by an external organisation, or
- make a self-determination and declaration of conformance with the Standard.221
It is intended that all requirements under the Standard are incorporated into the organisation’s OHSMS, however ‘the extent of the application will depend on such factors as the OHS policy of the organisation, the nature of its activities and the conditions in which it operates.’222 As such, AS4801 is a voluntary standard, which an organisation may choose to partially implement according to its needs.
Professor Cliff told the Board that compliance with AS4801 requires a risk assessment process to be undertaken in respect of all hazards in a workplace, not just hazards with the potential for multiple fatalities such as ‘major mining hazards.’223
The definitions of key concepts which apply under the Standard are detailed in Figure 3.18.
Figure 3.18 Definitions of key concepts under AS4801224
|Term||Definition||Paragraph of AS4801|
|Control of hazards/risks||The process of elimination
or minimization of risks.
|Hazard||A source or a situation with a potential for harm in terms
of human injury or ill-health, damage to property, damage
to the environment, or a combination of these.
|Hazard identification||The process of recognizing that a hazard exists and
defining its characteristics.
|Hazard/risk assessment||The overall process of estimating the magnitude of risk
and deciding what actions will be taken.
|Incident||Any unplanned event resulting in, or having a potential
for injury, ill-health, damage or other loss.
|Risk||(In relation to any potential injury or harm) The likelihood
and consequence of that injury or harm occurring.
|Safety||A state in which the risk of harm (to persons) or damage
is limited to an acceptable level.
The Standard requires that an organisation establishes and maintains an OHSMS in accordance with the following requirements (among others):
- Paragraph 220.127.116.11: The organization shall establish, implement and maintain documented procedures to ensure that the following are conducted –
(a) hazard identification
(b) hazard/risk assessment
(c) control of hazards/risks; and then
(d) evaluation of steps (a) to (c).
- Paragraph 18.104.22.168: The identification of hazards in the workplace shall take into account:
(a) the situation or events or combination of circumstances that has the potential to give
rise to injury or illness
(b) the nature of potential injury or illness relevant to the activity product or service; and
(c) past injuries, incidents and illnesses.
- Paragraph 22.214.171.124: All risks shall be assessed and have control priorities assigned, based on the established level of risk.
- Paragraph 126.96.36.199: All risks, identified through the assessment process as requiring control, shall be controlled through a preferred order of control methods (commonly referred to as a hierarchy), based on reasonable practicability. Elimination shall be the first control method to be considered.225
The Standard also notes that while undertaking hazard identification and hazard/risk assessments consideration should be given to adverse conditions arising from:
- normal operating conditions
- abnormal operating conditions, including shut-down and start-up conditions, inclement weather and foreseeable misuse
- incidents, and potential emergency situations
- past activities, current activities and planned activities.226
In the context of an incident such as a bushfire, this means hazard identification and risk assessments should consider adverse conditions such as weather conditions, the proximity of plantations, power failures, insufficient water supply and the unavailability of CFA resources during extreme bushfire risk weather due to other fire emergencies in the region.
During the public hearings, Mr Incoll suggested that a risk assessment would take into account the potential loss of power or water supply and, if that is likely to happen, consider what alternative supply arrangements are available.227
Professor Cliff further noted that as part of a risk assessment, it would not be unreasonable to assume that the capacity of the CFA to respond could be hampered by the need to deal with other fires in the region during peak fire season. According to Professor Cliff, if a thorough risk assessment is carried out, issues such as incapacity of the CFA to respond, the loss of power, faulty pipes and pumps could all be flagged as potential problems and additional controls put in place.228
The GDF Suez Safety Management System
As Hazelwood mine is a ‘prescribed mine’, GDF Suez is required to have a safety management system under r. 5.3.21 of the Occupational Health and Safety Regulations 2007 (Vic) (OHS Regulations) (see Chapter 3.2 Regulation of fire risk at the Hazelwood mine).
GDF Suez provided to the Board a folder comprising 21 documents and running to several hundred pages, which it submitted constituted its Safety Management System (SMS) prepared in accordance with r. 5.3.21 of the OHS Regulations.229 GDF Suez did not provide the Board with a copy of the Safety Management System Manual (document 1 of the GDF Suez SMS) until the evening prior to Professor Cliff giving evidence on 12 June 2014. The complete 21 document GDF Suez SMS was provided to the Board after Professor Cliff gave evidence.230
Document 1 of the SMS is the GDF Suez Safety Management System Manual. According to the Manual, the SMS ‘aims to apply best practice hazard management techniques to systematically identify and manage the Health and Safety risk that may be associated with the business of the company’ and is designed to comply with the requirements of various standards, including AS4801.231
Document 2 of the SMS is the GDF Suez Health and Safety Policy. Under this Policy, GDF Suez commits to:
- taking a proactive approach to health and safety requirements at all levels of the business and in all decision-making processes
- meeting or exceeding all health and safety statutory obligations
- maintaining a SMS and regularly reviewing its effectiveness to achieve improvement: ‘The effective Health and Safety Management System will be certified to comply with OHSAS 18001 and AS/NZS 4801’
- identifying, reporting investigating and resolving all safety related incidents, taking action
to prevent recurrence and monitoring the effectiveness of control methods.232
Document 3 of the GDF Suez SMS is entitled ‘Hazard Identification Risk Assessment and Control’. It documents ‘the method by which risks and hazards at IPR-GDF Suez Hazelwood will be managed, identified, recorded, assessed and controlled.’233 Clause 5 of this document, under the heading ‘Hazard Identification’ recognises GDF Suez’s obligation under r. 5.3.23 to ‘conduct a comprehensive and systematic safety assessment to provide a detailed understanding of all aspects of risks to health and safety associated with major mining hazards.’234
The Board notes that there is no reference in cl. 5 or elsewhere in the Hazard Identification Risk Assessment and Control document to the identification of mining hazards falling short of the definition of ‘major mining hazards’, that is hazards such as mine fires that do not have the potential to cause more than one fatality.
Under cl. 12 of the Hazard Identification Risk Assessment and Control document, ‘all hazards identified shall have a risk assessment conducted…to determine the likelihood and the probability of consequences from a hazard.’235 However, the requirement to conduct risk assessments in relation to all identified hazards is limited to ‘major mining hazards’, as this is the only type of hazard required to be identified under cl. 5.
Document 4 of the SMS is the GDF Suez Hazard and Risk Register, which bears the subtitle ‘Risk Assessments of Major Health & Safety Hazards at GDF Suez Hazelwood, Power Station and Mine.’236 Notwithstanding the reference to ‘major hazards’ in the subtitle, this document purports to be a comprehensive analysis of all mining hazards at the mine (not just major mining hazards), and identifies hazards, likelihood, consequence, risk rating, control measures and residual risk.237
The Hazard and Risk Register is 44 pages long and identifies 102 hazards. The hazard of most interest to the Board is ‘Fire’.238 The Register makes reference to major and minor fires but only in the operational areas of the mine (ie dredgers and station bunkers). It notes that there are ‘minimum risks to personnel’ and higher risk to plant and buildings.239 However it makes no reference to the hazard of fires in the worked out areas of the mine, nor does it refer to the possible consequence of harm to people outside the mine.
Due to the late provision of the GDF Suez SMS to the Board, Professor Cliff was not able to express any opinion in his expert report as to whether it satisfied r. 5.3.21 of the OHS Regulations. However, in the course of giving evidence during the public hearings and after only having reviewed the Safety Management System Manual (document 1 of the GDF Suez SMS) that morning, Professor Cliff noted that ‘the development of a safety management system under the legislation relates to mining hazards as well as major mining hazards’ and he ‘had no evidence of the risk assessments that would underpin them.’240
Under r. 5.3.23 of the OHS Regulations, GDF Suez is also required to conduct a comprehensive and systematic Safety Assessment in order to assess the risks associated with major mining hazards (see Chapter 3.2 Regulation of fire risk at the Hazelwood mine).
From 2003 to 2004, a Major Mining Hazards Safety Assessment comprising the following four documents was prepared for GDF Suez with the assistance of Qest Consulting:
- Safety Assessment of Major Mining Hazards: Stage 1 – Identification of Major Mining Hazards (dated December 2003)
- Safety Assessment of Major Mining Hazards: Stage 2 – Semi-Quantitative Risk Assessment
(dated February 2004)
- Safety Assessment of Major Mining Hazards: Stage 3 – Critical Control Adequacy Assessment & Reduced Case Risk Assessment (dated March 2004)
- Executive Summary: Safety Assessment of Major Mining Hazards (dated April 2004).241
The Executive Summary describes the Safety Assessment process as follows:
The assessment was aimed at achieving compliance with the requirements for a Safety Assessment as per the Occupational Health and Safety (Mines) Regulations 2002. A Major Mining Hazard is defined under these Regulations as; “a mining hazard that has the potential to cause an incident that causes, or poses a significant risk of causing, more than one death”242
As part of the 2003/2004 Safety Assessment, GDF Suez identified 53 mining hazards, of which 17 were considered to be major mining hazards. Relevantly, a ‘major mining plant fire’ was identified as a major mining hazard and was evaluated as being a ‘rare’ occurrence but with potentially ‘catastrophic’ consequences.243
Professor Cliff explained that the term ‘catastrophic’ in the context of risk assessments is a term of art and refers to ‘things that have the potential for significant harm like multiple fatality or very large economic or health effects from limited events.’244
For the purposes of the 2003/2004 Safety Assessment, major mining plant fires were characterised as set out in Figure 3.19.
Figure 3.19 Extract from Appendix 1 to ’Safety Assessment of Major Mining Hazards:
Stage 1 – Identification of Major Mining Hazards‘245
MH No. Hazard
|Hazard Name||Major mining plant fire|
|Description||Conveyors, stacker, dredger. Dredger considered biggest risk issue.
Areas of concern: Coal build up and mechanical failure.
|Causes||1. Electrical / mechanical failure 2. Grease build up 3. Coal build up 4. Hot work
5. Housekeeping 6. External fire 7. Lightning 8. Spot fire from vehicle / plant 9. Belt fire
|Likelihood / Probability||E Rare|
|Controls (Preventative)||1. PM (Condition monitoring, Lubrication), Shiftly inspection, Temperature censors /protection.2. Degreasing of plant, Shift inspections.3. Design to prevent spillage, PM, cleaning daily or on request (hose down / shovel clean), shiftly inspections, safety walks.4. Permit system, Follow up inspections, Training of fire man / spotter for Hot Work.5. Cleaning daily or on request (hose down / shovel clean), shiftly inspections, safety walks.6. Perimeter slashing, Fire brakes, On-site fire fighting tankers.7. Lightning rods on major plant.8. Modified exhausts, Modified braking systems, vehicle washing, PM, Ongoing inspection, Diesel powered vehicles.9. Preventative maintenance program, Shiftly fault inspections, competent maintenance personnel / operators, works management system (priority for safety items), FRAS belts.|
|Controls (Mitigation)||Fire extinguishers on all plant. Monthly visual inspection of extinguishers, Annual testing
of extinguishers, Reticulated fire water protection to all major mining plant. Annual training
in fire fighting. LV fitted with hoses. Escape routes from MMP, Emergency response procedures. Adequate fire water pressure and supply. Annual spray pattern testing.
On-site fire fighting tankers.
It can be seen from Figure 3.19 that the 2003/2004 Safety Assessment was focused on the causes, likelihood and consequences of a major fire breaking out in those parts of the mine where coal is actively mined.
In October 2009, GHD was commissioned to facilitate Safety Assessments concerning major mining hazards at the Hazelwood Mine.246 GHD’s work culminated in a report titled ‘Report for Major Mining Hazards Assessment: Interim Submission’, dated 22 December 2009.247
The Safety Assessments were conducted using a team-based approach over the course of four workshops in December 2009, which were attended by consultants from GHD, GDF Suez personnel working in various capacities at the Hazelwood mine, and others.248
The Safety Assessments involved:
- reviewing the 2003/2004 work referred to above to assess recognised major mining hazards against the definition of major mining hazards in the OHS Regulations
- using the workshop exercise ‘to identify representative, reasonable and thoroughly defined risk scenarios that have the potential to lead to a multiple fatality’
- for each scenario, identify current controls and select ‘Critical System’ and ‘Risk’ controls
- develop performance standards for all identified ‘Critical System’ and ‘Risk’ controls.249
As part of the Safety Assessment, ‘bow-tie’ diagrams were developed for each of the 17 identified major mining hazards.250 A bow-tie is a diagrammatic representation commonly used in risk assessments that identifies the causes, outcomes and risk controls for a particular hazard. An example of a bow-tie diagram is depicted in Figure 3.20 below.
Figure 3.20 Bow-tie diagram format251
Professor Cliff explained that:
A normal bow-tie diagram has an event, an unwanted event in the middle, the knot in the bow-tie. On the left-hand side you have the causes, on the right-hand side you have all the consequences, and between the causes and the event, you have the preventative controls; between the unwanted event and the consequences you have the mitigated controls. Now, controls are actions, barriers, that prevent or mitigate the event. So they’re not things like a piece of paper or a plan, they are firefighting system, they are automatic controls, they are evacuation, they are self-contained self-rescuers, so they are things you can identify as being able to control something.252
Prior to the workshop process, earlier versions of bow-tie diagrams produced in 2004 were validated and updated by a team consisting of a GHD consultant, a member of the mine’s management, the Mine Asset Manager and a safety representative. This process involved itemising ‘all known, reasonably foreseeable causes associated with each [major mining hazard] group.’253 The workshops then reviewed the bow-tie diagrams in detail, discussing the credible risk scenarios and controls.254
Relevantly, the bow-tie diagram for ‘mine fire’ identifies bushfire and spontaneous combustion
as potential causes.255
The 2009 GHD report recommended that GDF Suez carry out the following tasks:
- risk assessments for each of the scenarios for the seventeen identified major mining hazards illustrating that risk has been reduced to as low as reasonably practicable
- develop performance standards around each of the critical system and risk controls identified during the safety assessment workshops, including an assessment of the current adequacy of each control.256
As noted in Chapter 3.2 Regulation of fire risk at the Hazelwood mine, on 20–21 June 2012, VWA conducted a verification inspection of the Hazelwood mine in relation to mine fires arising from operational plant.257
On 21 June 2012, VWA inspector Mr Hayes issued an improvement notice requiring GDF Suez to ‘conduct a comprehensive and systematic Safety Assessment in order to assess the risks associated with the major mining hazard, mine fires.’258
In the improvement notice, Mr Hayes noted that:
- The 2009 GHD report recommended that ‘risk assessments are to be carried out for each of the scenarios for the MMHs [major mining hazards] illustrating that risk has been reduced to as low as reasonably practicable.’
- The operator of the Hazelwood Mine informed him that the risk assessments contemplated by the 2009 report were incomplete.
- The Safety Assessment documentation relating to ‘mine fires’ he observed was incomplete and unfinished.
- ‘If a mine fire was to occur whilst employees are performing duties within the mine, the fire has the potential to cause an incident that would pose a significant risk of causing, more than one death due to asphyxiation or burns.’
- ‘A failure to assess the risks associated with the Major Mining Hazard Mine Fires and to conduct a comprehensive and systematic Safety Assessment in accordance with regulation 5 3.23, may lead to hazards and failure scenarios not being identified and risk control measures not being implemented, thus exposing employees to a mine fire. A mine fire has the potential to result in multiple fatalities.’259
In response to the improvement notice, a working party of GDF Suez employees met on 4–5 October 2012 to review the risk scenarios, control measures and performance measures set out in the existing bow-tie diagram for mine fire and evaluate whether the risk had been reduced to as low as reasonably practicable.260
The working party determined that a mine fire satisfied the definition of a ‘major mining hazard’ under the OHS Regulations and agreed that to define a major mine fire as ‘any fire that is beyond the capability of the mine fire crews in attendance and requires external resources (CFA) or cannot be controlled within 30 minutes.’261
As a result of the working party review, several scenarios, risk controls and performance measures were revised. In particular, a new mine fire scenario was developed to address the risk of fire developing from geological hot spots.262
Following the working party review, in October 2012, a new bow-tie diagram and revised system control descriptions were developed for ‘major mine fires’.
On 8 October 2012, VWA conducted a follow-up visit and found that the review of the Safety Assessment had been completed to the satisfaction of the VWA, and that GDF Suez had complied with the improvement notice.263
The updated bow-tie diagram identified ‘bushfire’, ‘spontaneous combustion’ and ‘hot spots’ as potential causes of a major mine fire. For bushfire, the following preventive controls were identified:
- weather monitoring (under the Mine Fire Service Policy and Code of Practice)
- designated fuel storage area
- fire-breaks (under the Mine Fire Service Policy and Code of Practice)
- grass cutting (under the Mine Fire Service Policy and Code of Practice)
- daily preparation plans
- annual fire training.264
An identified control for spontaneous combustion was covering waste coal in worked out batters, the mine floor and overburden dump in compliance with the Mine Fire Service Policy and Code of Practice.265 However, as noted above, under s. 3.4 of the Mine Fire Service Policy and Code of Practice, there is only a requirement to cover coal in worked out batters if there are no tanker filling points or hydrant manifolds within five minutes travel.
Professor Cliff identified a number of critical shortcomings in the bow-tie diagram and system control descriptions developed in October 2012.
Professor Cliff told the Board that the documents do not identify fire in the worked out batters as a specific hazard.266 In Professor Cliff’s experience, mine fire risk assessments are ‘location-specific’ and ‘scenario-specific’.267 Based on prior incidents experienced at the Hazelwood mine, a fire in the worked out areas is a particular type of mine fire that needs to be managed and Professor Cliff told the Board he would have expected to see this treated as a separate hazard.
Professor Cliff also told the Board that the system controls identified do not address ember attack as a specific scenario that could cause a fire in the worked out areas of the mine. Professor Cliff found it surprising that ‘there appears to have been no consideration of where these embers could lodge within the mine other than the active working areas…given the sheer surface area of the abandoned areas and the associated large expanse of coal.’268
Further, it is apparent from the GDF Suez bow-tie diagram that it does not include the kinds of impacts that Professor Cliff would have expected to see listed on the right hand side of the bow-tie diagram, such as multiple fatalities, injury, damage to plant, loss of asset, loss of production and harm to local the community.269
Professor Cliff advised that there did not appear to have been any consideration or testing of risk controls to determine whether such controls were effective under adverse conditions such as the inability of the CFA to respond during peak fire season, loss of power or failure of pipes and pumps.270
Mr Incoll also observed in relation to the Safety Assessment that:
The framework for Occupational Health and Safety in relation to fire in the proximity of the Mine has been extensively developed… However the same audit process was not conducted into incursions by external fires, despite the history of rural fire affecting mining operations since at least 1944. Apart from seasonal break preparation and vegetation management, the framework for responding to the external fire threat only commences operation when a fire is a threat to the Mine, that is reactively rather than proactively by identifying and mitigating hazards outside the Mine boundary.271
Professor Cliff initially formed the view that the bow-tie diagram and system control descriptions developed in October 2012 did not satisfy the requirements under r. 188.8.131.522 However, Professor Cliff did not have the 2003/2004 Safety Assessment and 2009 GHD report when preparing his expert report.273 After being shown these documents, he conceded that they did provide the basis for a Safety Assessment that met the requirements of r. 184.108.40.2064
However, Professor Cliff also maintained that the documents did not address the issue of fire in the worked out areas of the Hazelwood mine, ‘because they only refer to multiple fatality under the major mining hazard feature.’275
RECOMMENDATIONS ARISING FROM REVIEWS OF PREVIOUS FIRES AT THE MINE
Past fires at the Hazelwood mine
As noted in Chapter 2.1 Origin and circumstances of the Hazelwood mine fire, open cut coal operations are high-risk environments for fire. Given the volatility of brown coal, it is not unusual that the Hazelwood mine experiences several fires in any given week.276 Prior to privatisation, it appears there were between 200 and 400 fires a year.277 The vast majority of fires experienced at the Hazelwood mine are minor fires that affect actively mined areas of the mine and are quickly suppressed without any requirement for CFA assistance.278 These fires are generally caused by a mechanical fault of some sort, for example a bearing seizing in an idler resulting in sparks being generated, or a flare up of a pre-existing geological hot spot.279
In the early 1990s, there were around 10–20 fires a year in the worked out areas of the mine.280 There was evidence that, at that time, the majority of fires in the worked out areas resulted from welding associated with the repair of leaking pipework.281 The exact incidence of fires in the worked out areas in recent years was unable to be determined during the course of the Inquiry.282
To Mr Dugan’s knowledge, none of the previous fires at the Hazelwood mine was caused by external bushfires. In Mr Dugan’s 35 years’ experience in the Latrobe Valley brown coal mining industry, he was not aware of any fire being caused in the Hazelwood mine as a result of external bushfire, prior to the Hazelwood mine fire in 2014.283 While this might be true of the Hazelwood mine, the risk of bushfire resulting in a major fire in an open cut brown coal mine is well known and has occurred before in the Latrobe Valley. The Yallourn mine fire in 1944 was caused by an external bushfire and became the subject of the Stretton Royal Commission. Bushfire risk is also explicitly acknowledged in the GDF Suez Mine Fire Service Policy and Code of Practice.284
The Hazelwood mine also experienced a well-publicised fire in 1977 (recommendations arising out of which led to the creation of the initial 1981 Policy and Code, as discussed above).285
Since privatisation, there have been a number of significant fires, which are outlined in Figure 3.21 below.
Figure 3.21 Recent fire history at the Hazelwood mine
|Date fire started||Cause of fire and brief description|
|12 February 2001||A fire occurred on the Energy Brix coal supply conveyor. The fire was most probably caused by a bearing failure on a return idler. CFA personnel brought the fire under control within approximately one hour of it being detected. No one was injured. An internal investigation into the incident subsequently identified that the mine’s Management System did not detect the failure on the conveyor.286|
|15 November 2003||Spot fires spread to the main slot coal bunker. The cause of the first fire was not able
to be determined. The most significant fire was controlled by approximately midnight.
About 100 CFA and other personnel fought the fires. No one was injured. An internal investigation into the incident found that high temperatures and strong winds contributed
to the spread of the fire.287
|3 April 2005||A fire developed on conveyors M171 and M172 and spread to the main coal bunker. Both the CFA and the Metropolitan Fire Brigade provided assistance to fight the fire. No serious injuries were caused. The Mining Regulator directed the mine operator to conduct a risk assessment for combatting fires at height. An internal investigation was carried out and recommended a number of improvements in emergency response and firefighting.288|
|30 December 2005||A major fire established in the south-east field, which by that time was no longer being mined. Fire in an old geological hot spot spread as a result of hot temperatures and strong north-westerly winds. CFA crews from local brigades were not able to attend due to other fires in the area and CFA crews largely unfamiliar with mine fires attended the fire. The fire was ‘controlled’ by 1 January 2006 and was declared ‘safe’ by 5 January 2006.289|
|12 October 2006||An idler overheated and a mine conveyor unit caught fire. The fire caused extensive damage to the plant within the mine, valued at approximately $30 million. The fire
was suppressed on 18 October 2006, and salvage works continued for several days following the fire.290
|Date fire started||Cause of fire and brief description|
|14 September 2008||The fire started at approximately 12.45 pm, caused by an ignition from the same
hot spot in the worked out areas that caused the December 2005 fire. Personnel were unable to mount an effective initial response to the fire due to difficult access to the worked out areas and insufficient firefighting facilities, and the fire spread. The CFA were not able to attend for two hours. The fire was controlled by 17 September 2008.291
|21 January 2012||The D11 dredger caught fire as a result of faulty idler overheating and igniting coal
and rubber on a conveyor. Fire did not appear to spread to the coal surface (which
was 12 metres below the dredger), and was isolated to the machine itself. The fire flared and was difficult to contain because of a time delay in securing an external water supply to extinguish the fire. The fire was extinguished by 4 pm on 21 January 2012.292
Investigations and reviews into past fires
In respect of each of these incidents, either GDF Suez or independent consultants who GDF Suez retained, carried out an investigation and produced an incident report with a series of recommendations. The relevant regulator at the time became aware of all of these incidents and took a varying level of interest, depending on the nature and particular features of the fire and its approach to regulation (see Chapter 3.2 Regulation of fire risk at the Hazelwood mine for more detail).
All of these previous incidents form part of the history of fires at the Hazelwood mine and lessons can be learnt from them. The December 2005 and September 2008 fires were of particular interest to the Board, as they concerned fires that took hold in worked out areas of the mine. Although considerably smaller in scale and caused by hot spots, rather than bushfire, there were a number of similarities between these fires and the Hazelwood mine fire in 2014.
Notably, the internal investigation into the December 2005 fire found that:
- The fire broke out between levels 3 and 5 on a coal face which was 30 metres high and difficult to reach.293
- The mine’s tanker was unable to quickly respond to the initial outbreak of fire, as it was being
used to combat a grass fire elsewhere in the mine. By the time the tanker was en route, it became apparent that CFA assistance would be required.294
- There were limited personnel available due to the holiday period so employees on leave were called upon to form fire and relief crews.295
- CFA crews from the Latrobe Valley who were familiar with coal mine fires could not attend due to ongoing fires in the region (Region 10). CFA crews from Region 8 Western district were called. These crews, although competent at fighting bushfires, appeared unsure and hesitant on how to attack a coal fire.296
- Although water supply was reliable within the designated fire area (in the south-east batters), ‘further consideration should be given to ease of access, location and reliability of water supply in other worked out sections of the mine, specifically the north-eastern batters of the mine.’297
- ‘Where ever [sic] practically possible fire-break zones extending down the full depth of each batter may be utilised such that the length of exposed coal in any one batter is not greater than 500 m. These zones can be in the form of metalled vehicle access ramps or clay covering a minimum or 8 m wide.’298 This recommendation reflected the alternative fire measure already specified in s. 3.4 of the Mine Fire Service Policy and Code of Practice.
The September 2008 fire was caused by the same hot spot as the December 2005 fire. Following the 2005 fire, the hot spot was covered in clay and monitored, but spots such as this can flare up unexpectedly, for example due to wind getting through cracks in the coal.299
GDF Suez engaged GHD to investigate the September 2008 incident. The GHD report into the 2008 fire noted that:
- It is essential that GDF Suez is ‘able to mount a decisive initial response to prevent small fires escalating into large fires. This is particularly important out of normal work hours when manning levels are very low. It takes CFA up to two hours to mobe [sic] a full response of sufficient resources to combat significant fire’ at the Hazelwood mine.300
- ‘The significant factor in this fire was the escalation into an uncontrollable fire within a short time due to [mine] personnel being unable to mount an effective initial response as the non-operational areas have very difficult access and there were insufficient fire-fighting facilities available.’301
- At some stage prior to the incident, ‘the fire water pipe that supplied this non-operational section of the mine had been damaged and the fire water isolated.’302
The Board was particularly interested in recommendation 6 of the GHD report into the September 2008 fire in the worked out areas of the Hazelwood mine:
A risk assessment should be undertaken on the non-operational areas to determine if further prevention work is required. The risk assessment should include a Cost/Benefit Analysis.
A range of options have been identified in terms of prevention of hot spots from reigniting and detection of hotspots.303
The draft version of this recommendation read as follows:
A risk assessment should be undertaken on the non-operational areas to determine if further prevention work is required. The risk assessment should include a Cost/Benefit Analysis.
A critical element of the initial response and the ongoing emergency response was the lack of fire water supply to the non-operational areas and the restrictions in access due to the conditions of the roads, the accumulation of debris and that some batters did not have road access.
The annual audit should include fire water supply to non-operational areas, access and housekeeping.
A range of options were identified in the brainstorming session (refer Appendix B) in terms of prevention of hot spots from reigniting and detection of hotspots.304
GDF Suez has revisited recommendations arising from previous significant fires on a number of occasions. GDF Suez also maintains a software system known as Paradigm II to manage compliance and allow employees to track the implementation of actions arising from incidents at the Hazelwood mine.305
The report into the October 2006 fire included a review of the recommendations arising out of the 1977 fire at the Hazelwood mine.306 The report into the September 2008 fire also reviewed the implementation of recommendations arising out of the October 2006 fire and found that all of those recommendations had been implemented.307 The Mining Regulator oversaw implementation of these recommendations, including a review of the Mine Fire Service Policy and Code of Practice.308
The recommendations arising out of the January 2012 fire have also been fully implemented.309
GDF Suez submitted that its implementation of recommendations arising from reviews of previous incidents has led to improvements in its fire management procedures.310 GDF Suez provided the following examples of such improvements:
- training exercises with the local CFA
- refined techniques for fighting coal fires (eg the use of a 30,000 litre water tanker as the first responder to any fire emergency)
- the implementation of procedures under which Mine personnel escort the CFA throughout the mine
- updating the following fire policy documents:
- Mine Fire Service Policy and Code of Practice
- Emergency Response Plan
- Mine Fire Instructions
- the preparation of the following additional fire policy documents:
- Guidelines for Season and Period Specific Fire Preparedness and Mitigation Planning
- Guidelines for Season Specific Fire Preparedness and Mitigation Planning
- Check List For Fire Fighting Equipment Annual Audit and Inspection
- Check List For Season Specific Fire Preparedness and Mitigation Planning.311
In June 2012, Mr Stan Kemsley, GDF Suez Mine Technical Compliance Manager, conducted an audit of the implementation of recommendations from the fires in April 2005, October 2006, September 2008 and January 2012. Mr Kemsley’s report (dated 29 June 2012) includes a table, which lists the recommendations from each incident and states whether they have been addressed and whether they have, in Mr Kemsley’s view, been effective.312
The implementation of recommendations arising from the review of the December 2005 fire in the worked out areas of the Hazelwood mine was not included as part of Mr Kemsley’s audit. However, it is clear that the recommendation in the relevant incident report concerning the formation of clay fire-breaks313 was not implemented.314 The reason for not doing so is clear from the evidence of Mr Polmear and Mr Faithful referred to in detail above—it was not practicable in areas where the profile of batters in worked out areas is extremely steep.
Critically, Mr Kemsley found that recommendation 6 of the September 2008 report had not been implemented.315
Mr Romeo Prezioso, GDF Suez Senior Mine Planner, was the Fire Service Officer at the time of the September 2008 fire and listed a range of measures that GDF Suez had implemented in response to recommendation 6. These included:
- From about February 2009 to April 2013, the production of a Monthly Hotspot Inspection Report with respect to the known hotspots (as identified by Mr Prezioso).
- From about December 2012, inclusion of the results of regular Fire Hot Spot Status reports as part of the Fire Management Systems – Weekly Status “Rag Reports”.
- The removal of disused mining infrastructure, such as a conveyor and ARMCO vehicle crossing from the southern batters of the Hazelwood mine, and the realignment of a road, in order to improve access.
- The enhancement of the annual firefighting equipment audit to more comprehensively address the worked out areas of the Hazelwood mine. The annual audit now assesses access conditions and the condition of the fire services infrastructure at the worked out areas of the Hazelwood mine.
- The digging out and recapping of known hot spots with clay.
- The use of thermal imaging cameras, and consideration of the use of buried thermocouples.316
The audits of fire services infrastructure referred to by Mr Prezioso were said to include the reticulated fire service pipes in the area and resulted in various improvements being made to the water supply, including the repair or installation of new pipes, valves, sprays and other mechanisms.317 However, Mr Prezioso said that the purpose of the audit was not to evaluate the effectiveness of the existing fire service network, but ‘to assess [that] what was on site was operational and functional.’318 As a result, no additional pipework was installed in the northern batters in response to the September 2008 fire or the audits of the fire service network that followed.319
Mr Prezioso also conceded that no risk assessment had been conducted as recommended.320
Mr Prezioso explained that he understood the key concerns behind recommendation 6 were:
- improving access to worked out batters such as the southern batter
- ensuring early detection of ‘flare ups’ of hot spots within the Hazelwood mine.321
Mr Prezioso was inviting the Board to conclude that GDF Suez had implemented the spirit of the recommendation, if not the letter.