17 The respondent has no prior convictions. The maximum penalty for each offence is $550,000. Those facts are not in issue.
18 On behalf of the respondent, evidence was received in affidavit form from:
(i) Mr Anthony Quin: Mr Quin is currently employed by the BHP Billiton Group as Senior Commercial Manager of the Energy Coal Division.
Mr Quin's affidavit deposes to the change in the respondent's corporate history since the accident at Wallarah Colliery in July 1998. There was no issue as to his evidence on those matters and he was not required for cross examination.
(ii) Mr Peter Hayes: Mr Hayes currently operates as a consultant via his company PJH Consulting. In July 1998, Mr Hayes was the General Manager of the Wallarah Joint Venture which owned and operated the Wallarah Colliery.
At the time of the accident in July 1998, Mr Hayes had 24 years of experience in operations and management of coal mining operations, both underground and open cut.
Mr Hayes' affidavit was extensive with considerable annexed material. He was required for cross examination.
19 The proper consideration of the objective seriousness of the offences requires an understanding of the factual circumstances that ground the offences.
20 A crew of five miners commenced a night shift at the Wallarah Colliery at about 11:00pm on 5 July 1998. At that time, the Colliery was mining the Great Northern Seam. Those five comprised Mr Tytherleigh as Deputy and the four mine workers Anthony Carroll, Tony Dickson, Noel Pezely and Russell Anslow.
21 The mining activity being undertaken at that time was operating under support rules for first workings in the Great Northern Seam. Those support rules had been made and approved pursuant to the provisions of ss 102(1) and 105 of the Coal Mines Regulation Act 1982 respectively. Those support rules provided:
[1] During face advancement, a test hole is to be drilled at 3m centres at any place across the roadway, with a minimum depth of 0.9m. As appropriate, temporary support may be placed (at maximum 3m intervals) until such times a test hole is drilled.
[2] The maximum distance of exposed roof beyond the last test hole or temporary roof support, to the face shall be 10m.
[3] Workmen are not to proceed beyond the last test hole or temporary support unless the roof has been tested by sounding with a metal bar or suitable metal object & found secure.
[5] Four way intersections are to have a minimum of 5 bolts, a minimum of 1.0m in length, located in similar positions as shown in the diagram. ie; One bolt in each quadrant & one in the approximate centre. This shall be completed immediately after the formation of the intersection.
[6] A mining official may direct that additional support above the described minimum rules be installed when roof conditions deteriorate.
[7] Roof Supports are to be installed to resin installation standards as displayed by the manufacturer.
22 The crew of miners earlier referred to were working in an area in close proximity to and running at a shallow angle more or less parallel with a fault zone. At a point in the work, the crew encountered a large amount of water at or adjacent to the 2 CT intersection. The water was coming from the fault which had been hit and the crew spent some ninety minutes pumping the water out.
23 As mining activity continued, the mine crew hit the fault at the heading. It was reported to the Under Manager, Mr Wallace, who came to inspect the worksite. Mr Wallace gave instructions to the Deputy, Mr Tytherleigh, that mining was to cease and that he wanted 'extra support put up, plus a row of props along the edge of the fault, and then I wanted the area taped off'.
24 As part of the discussion between Mr Wallace and Mr Tytherleigh, it was decided to square up the end of the heading before finishing. Accordingly, after Mr Wallace gave his instructions, mining activity continued with double bolting 1.5 metres apart.
25 During Mr Wallace's inspection of the worksite, he sounded the roof and assessed it as competent. That procedure was described by Peterson J at first instance as follows:
[28] ... The standard means of testing the roof is to strike it with a length of drill steel in a process called "sounding the roof". A solid ring will be accepted as indicating a sound roof whereas a hollow or flat sound induced by the steel will indicate a "drumminess" of roof, perhaps inducing an increase in the number of bolts applied to the roof.
26 The sounding of the roof of the mine was undertaken as a part of the roof bolting process in order to support the mine roof. Supporting a mine roof is a critical part of mining activity. That support will consist of either temporary support in the form of timber props or permanent support by way of roof bolting. At the time of the incident, the latter was in use.
27 The process of roof bolting at the time of the incident was explained in our earlier judgment on liability as follows:
[68] In relation to the drilling machine being used, the evidence before his Honour was that, at the time of the accident, the drilling machine was a rotary percussive drill known as a Falcon Roof Bolter. As his Honour described at [30] of his judgment:
While the drill is sometimes referred to as a 'hand held' drill, the drill sits on top of a telescopic leg which extends by hydraulic action to push the drill machine up to the roof. The drill, the drill steel having been loaded into the top of the machine, is then operated by a control lock or lever.
[69] Reference to the hand held nature of the Falcon Roof Bolter would appear to be related to the need for the miners to manually manoeuvre the drill into position immediately under the roof to be bolted. That meant, generally speaking, when being used, the miners were working under unsupported roof. Again from his Honour's judgment there is evidence that, when the roof was 'bad', temporary support in the form of timber props were installed prior to the installation of the permanent support (bolts, primarily) using a roof bolting machine. Mr Mark Levey, the Mine Manager for Wallarah at the time of the accident gave evidence to that effect.
[70] The use of a hand held drill such as the Falcon Roof Bolter is to be distinguished from rig mounted bolting machinery that allows the operator to be under supported roof at any time. ...
[71] There was evidence that rig mounted bolting machines had been used at the Wallarah Colliery prior to the accident and were available to be used on 6 July 1998. Nevertheless, for reasons that we understand had to do with the clearance height of the mine in that area on 6 July 1998, a decision had been taken to proceed with the roof bolting using the Falcon Roof Bolter. The result of that decision was that at the time of the accident the miners operating the Falcon Roof Bolter were working under unsupported roof.
28 The practice of sounding the roof in the manner described by Peterson J at first instance was and is, by all accounts, an acknowledged method of assessing roof competency and it has been a practice in the coal mining industry for many years. On behalf of the respondent, both at first instance and before us, much was made of the fact that, at all times up to the time of the fatal roof fall, the roof continued to sound competent.
29 While that may be the case, such a procedure as a definitive method of assessing roof competency allied to a safe place of work has to be considered in light of the workplace circumstances then prevailing. In the present matter, the workplace situation presented as one that relatively quickly deteriorated to one of real and foreseeable risks to safety against which the respondent's system of work, in important respects, clearly failed. That failure centred around the need to ensure roof stability in underground mining activity.
30 The importance of roof stability in underground mining cannot be overstated. As we said in our judgment:
[87] We take the view that, in the context of the underground coal mining industry, the need to ensure the stability of the roof of the mine would be an essential factor in safely undertaking underground mining activity. As his Honour said at [84] of his judgment:
In the context of underground mining, it is difficult to perceive any necessary function more important to the safety of workers in the mine than the support of the roof.
[88] It is obvious that if the mine roof is not stable, there is a very real possibility of a roof fall with all of the attendant dangers and problems that such an occurrence would cause. The steps taken as part of mining activity to secure the roof by way of bolting and/or temporary supports evidence the importance of such an issue. As well, the legislative provisions already referred to reinforce the importance of having approved minimum support rules and the acknowledgment of the need to go beyond them when roof conditions deteriorate at any time. Overarching those specific legislative provisions in relation to that particular activity is the obligation on the mine operator to take whatever action may be necessary in the interest of safety (clause 9, Managers and Officials Regulation) as part of ensuring the health, safety and welfare of employees (or non-employees) at work, as required by s15 of the Occupational Health and Safety Act 1983 (or s8 of the Occupational Health and Safety Act 2000).
31 That the roof conditions at the relevant worksite on 5 and 6 July 1998 where the miners were working were unstable is without doubt. Once the mine workers encountered the fault with the attendant water problems and Mr Wallace attended and gave the instructions he did, the workplace situation further deteriorated. As we explained in our judgment:
[23] Mr Wallace was at the work area for about one hour. Just before he left, there was a roof fall consisting of some ply that had fallen out of the face plus coal tops had fallen.
[24] During the roof bolting process that continued after Mr Wallace left, water was coming out of the roof from the bolt holes. As well, the drill steel of the roof bolter was jamming, indicative, as his Honour found, 'of a poor roof.'
[25] Later in the shift, Mr Carroll and Mr Dickson returned from their crib break and took over the roof bolting process from Mr Anslow and Mr Pezely. In handing over to them, Mr Anslow reported, in the process of drilling a hole, he had noticed a parting in the hole that was evidence of a soft layer in the conglomerate.
[26] While Mr Carroll and Mr Dickson were bolting, they experienced problems with the air pressure in the Falcon roof bolter. While the air hoses were being checked, another fall occurred. This consisted of approximately six metres of stone. The roof had fallen back from the face to a point about 1.5 metres from where the last roof bolts had been installed.
32 As the facts disclosed, Mr Carroll and Mr Dickson continued to encounter problems with the bolting process. The drill steel became jammed in the roof. It was while attempting to free it by striking it with another steel that the third roof fall occurred, burying Mr Carroll, causing him fatal injuries and seriously injuring Mr Dickson.
33 The acknowledged indicia of roof instability that were present by the time the third roof fall occurred were:
(i) Ground water emanating from the roof and other parts of the area being worked;
(ii) Jamming of drill steels during bolt hole drilling and roof parting;
(iii) Prior roof falls;
(iv) Mining parallel to a known fault; and
(v) Guttering of ribs and roof condition deteriorating.
34 On that point we said at [98]:
Given the known indicia of an unstable roof and the importance of ensuring a safe and secure roof in underground mining activity, it is imperative that employers should identify with as much precision as possible, the known indicia of an unstable roof and the steps that are to be taken when such indicia exist. One of those steps would be to cease mining immediately until the situation had been properly risk assessed.
35 Against the background we have detailed, the risk to safety that presented itself was abundantly obvious. The risk to safety was the risk of a roof fall. The likely outcome of a roof fall in underground mining where miners are working is death and/or serious injury to employees. That is precisely what happened. In our view, in assessing the culpability of the respondent against the factual circumstances of the offences, the foreseeability of injury or accident was high and renders the offences more serious in nature.
36 In his affidavit evidence, Mr Hayes emphasised the steps taken by the respondent to put proper support rules in place. Those support rules, identified as minimum support rules, had been developed by the respondent and approved by the Department of Mineral Resources (DMR) pursuant to the relevant provisions of the Coal Mines Regulation Act. As Mr Hayes stated, 'approval ... by the DMR of the support rules was essential'.
37 The support rules were and are a vital step in ensuring the stability of the roof so that mining activity can proceed safely. In finding the offences proved, we determined in essence that the support rules were inadequate in not being sufficiently prescriptive. As we said in our judgment at [66]:
In short, there is a two-step decision-making process within the system of work - the assessment of the roof and the erection of roof support consequent upon that assessment.
38 The support rules in place at the time of the incident had two provisions that became specifically relevant to the factual circumstances of the offences. They were:
Rule (3): Workmen are not to proceed beyond the last test hole or temporary support unless the roof has been tested by sounding with a metal bar or suitable metal object and found secure.
Rule (6): A mining official may direct that additional support above the described minimum rules be installed when roof conditions deteriorate.
39 Dealing first with Rule (3). It was apparent at the time of the accident that the respondent placed great faith in the sounding of the roof, almost to the exclusion of all other indicia, as an indication the roof was stable and thereby safe. Certainly, the work circumstances evidenced a continuation in mining activity notwithstanding the indicia of roof instability. As we said in our judgment on liability at [98]:
For reasons not fully known but predominantly, it would seem, because the roof continued to sound competent, mining activity continued in order to square up the end of the heading before finishing. It was, on any view, an unwise and unsafe decision given the roof conditions then existing. Not only did mining activity continue but it persisted beyond a second and more extensive roof fall some time shortly after. Again, the continuing activity was justified by relying on sounding the roof as the determinant that it was safe to do so notwithstanding all indicia to the contrary. It is difficult to visualise a more unsafe system of work. Further, this unsafe system can be traced directly to the absence of any oral or written prescription designed to protect employees by identifying matters that, taken together, constituted a risk to safety at work and how they were to be addressed to safely and proactively deal with that risk.
40 Given the acknowledged indicia of roof instability present at the time, steps beyond a mere sounding of the roof were called for. Rule (6) clearly contemplated that by providing for 'additional support ... when roof conditions deteriorate'. In part, that is what Mr Wallace did do. Clearly, however, the minimum support rules were of little, if any, assistance as to what was expected to be done "when roof conditions deteriorate". On that point, we said as follows:
[95] There is no doubt that the minimum support rules were not sufficiently prescriptive as to what constituted unstable roof conditions and equally so, as to what was to be done, in any precise way, when such conditions did exist. But the failure pleaded goes beyond the minimum support rules to the actual system of work designed to deal with unstable roof conditions. The evidence before his Honour to which our attention has been drawn would indicate that beyond the minimum support rules and the discretion inherent in them to provide additional support 'when roof conditions deteriorate', there was nothing in any prescribed form that could be relied upon. There is the 'practice' that Mr Levey described and to which we have earlier referred. Relying on a somewhat loosely articulated practice within the industry as constituting a system of work above and beyond the minimum support rules is, on any view, inadequate when considered against the obligation to ensure a system of work that was absent a risk to the health and safety of the employees concerned subject, in this case, to s33(2).
...
[117] As is evident, there is no mention in the minimum support rules that directs work to cease in the circumstances prevailing at the respondent's worksite on 6 July 1998. That is, indicia of deteriorating roof conditions. Outside of the minimum support rules, there does not appear to be any evidence of a system of work that directed mining activity to cease below unsupported roof in circumstances of an unstable roof. On any view, given the clear risk to safety that such a situation presented to the workmen concerned, there should have been. There was, on the evidence, a decision taken by Mr Wallace when he first visited the worksite for work to cease. For reasons that have already been detailed, mining activity did continue. What we find difficult to comprehend is the decision presumably taken to press on with mining activity following the second, and seemingly more significant, roof fall that followed after Mr Wallace left. By that stage, circumstances demanded that work cease immediately in the face of an increasingly risk-laden situation at the workplace.
41 Within the context of assessing the respondent's culpability, Mr Hayes pointed to the careful and considered process undertaken to develop the support rules in place at the time of the accident. One of the sources that guided the development of the support rules was the Roof Support Guidelines for Massive Strata Conditions. Those guidelines were produced by the DMR, (now Department of Primary Industries) in 1994. Mr Hayes helpfully annexed a copy to his affidavit. Given they were in place at the time of the incident, it is surprising they were not before his Honour at first instance. If anything, they emphasise the need for the respondent to have had in place a comprehensive system of work in order to assess and ensure roof stability that went beyond the minimum support rules then in place.
42 The DMR guidelines make it clear the reason why they were developed. As the foreword signed by the then Chief Inspector of Coal Mines said:
Roof support has been a basic issue in Coal Mines for many centuries. Often roof material and/or depth of mining have required man made support to be installed regularly to maintain stability. Support under these conditions is mandatory not optional.