Robertson v Gillman Bros Mining Contractors Pty Ltd

[2007] WASCA 36

JURISDICTION     :   SUPREME COURT OF WESTERN AUSTRALIA

TITLE OF COURT  :   THE COURT OF APPEAL (WA)

CITATION:   ROBERTSON -v- GILLMAN BROS MINING CONTRACTORS PTY LTD [2007] WASCA 36

CORAM:   WHEELER JA

PULLIN JA
BUSS JA

HEARD:   16 AUGUST 2006

DELIVERED          :   15 FEBRUARY 2007

FILE NO/S:   CACV 66 of 2005

BETWEEN:   GRANT WILLIAM ROBERTSON

Appellant

AND

GILLMAN BROS MINING CONTRACTORS PTY LTD
Respondent

ON APPEAL FROM:

Jurisdiction              :  DISTRICT COURT OF WESTERN AUSTRALIA

Coram  :WISBEY DCJ

Citation  :ROBERTSON -v- GILLMAN BROS MINING CONTRACTORS PTY LTD [2005] WADC 95

File No  :CIV 1964 of 2001

Catchwords:

Tort - Negligence - Employer and employee - Alleged failure to provide proper plant and safe working environment - Causation - Challenges to trial Judge's findings of fact and law

Legislation:

Nil

Result:

Appeal dismissed

Category:    B

Representation:

Counsel:

Appellant:     Mr E J Myers

Respondent:     Mr M H Zilko SC & Mr C C Rimmer

Solicitors:

Appellant:     Bradley & Bayly

Respondent:     Jarman McKenna

Case(s) referred to in judgment(s):

Bankstown Foundry Pty Ltd v Braistina (1986) 160 CLR 301

Chance v Alcoa of Australia Ltd (1990) A Tort Rep 81‑017

Czatyrko v Edith Cowan University (2005) 79 ALJR 839

Dahl v Grice [1981] VR 513

Fernandez v Tubemakers of Australia Ltd [1975] 2 NSWLR 190

Purkess v Crittenden (1965) 114 CLR 164

Watts v Rake (1960) 108 CLR 158

Wilsher v Essex Area Health Authority [1988] 2 WLR 557

1. WHEELER JA:  I have had the advantage of reading in draft the reasons for decision of Buss JA.  I agree with those reasons and have nothing to add.

2. PULLIN JA:  I agree with Buss JA that the appeal should be dismissed.

3. Although there were many grounds of appeal, there were only two overall points involved.  I will deal first with the second of them. 

4. The complaint in grounds 12, 13 and 14 was that the trial Judge erred in concluding that there had been no breach of duty by the respondent.  The breach of duty alleged was that a seat was defective on 22 October 1999 or, alternatively, there was a breach of duty by reason of the failure to maintain defective roads and seats over a 20 month period.

5. The first allegation of breach was not supported by the evidence.  The evidence was that the particular vehicle the appellant was driving, a bogger numbered B 15, had its seat reported as defective on 3 September 1999.  A Mr McSkimming gave evidence that he changed the seat on 3 September.  There was no complaint about the seat thereafter.  Mr McSkimming also gave evidence that the seats were never left in damaged condition for weeks or months.  Mr John Gillman also gave evidence about the regular repair or replacement of seats if they were complained about.  Mr Stanley Gillman gave evidence that there were unallocated seats available for installation when they were needed.

6. As a result, the overwhelming evidence was that there was no defective seat on the machine on 22 October which could have caused any injury.  This allegation of negligence or breach of duty was therefore bound to fail. 

7. As to the alternative allegation of negligence, the evidence did not support the contention that there was a breach of duty.  Over the 20 month period the appellant complained once about a seat on 4 June 1999 and once about the road on 1 April 1999.  There were at least nine witnesses called who gave evidence about the roads and said that they were normal roads for a mine site.  The appellant called a worker to establish the bad condition of the roads and this witness, Mr McDonald, did not support the appellant's evidence in this regard.  The appellant relied heavily on documentary material to make out this case but, put in context, they reveal very few complaints about the roads.  Over the relevant period there were some 6000 "plods" which, if there had been written complaints about the seats or the roads, would have contained such complaints.  There were

only 37 plods identified by the appellant, 27 of them before 22 October 1999.

1. His Honour said, in [247] of his reasons for decision:

   "The evidence given by the defendant's witnesses, Stanley Joseph Gillman, Gregory Alan Gillman, Wayne Conway, John Kent Gillman, Craig Vincent McSkimming, Murray Lee Giles, Justine Vivian Leda, Brian Stephen Bosenberg and Graham Leonard Lindgard, was to the effect that: 

   (a)the roads within Golden Pig were serviceable and of an equivalent standard to those encountered at numerous other mine sites; 

   (b)the seats on the haul trucks and boggers were of a reasonable condition and adequately maintained; …"

2. This evidence was uncontradicted save for the evidence of the appellant, who gave what his Honour found was a "significantly exaggerated" account of the extent of deficiencies in the vehicle's seating, the condition of the roads and the forces applied to his body as a result of both.

3. His Honour then concluded at [248] and [249]:

   "248    I am satisfied on all of the evidence that there were occasions when one or more vehicles had defective seats, which were not promptly repaired or replaced.  Further that there were occasions when roads were below optimal standard and when there was a lack of adequate road base.  It is to be observed, however, that only a very small proportion of the plods tendered in evidence (37 out of approximately 6,000) complain about vehicle or road conditions.  The position is similar with the maintenance meeting minutes.  One would expect the position to be otherwise if the situation was as suggested by the plaintiff. 

   249The evidence establishes that underground mining is a harsh environment where road surfaces, vehicle seating and working conditions generally must of necessity be ever changing.  I am satisfied that the defendant had in place an appropriate maintenance and supervision system to respond to that environment.  Although deficiencies in the state of equipment and the condition of the roads are identified in the documentation referred to by the plaintiff, it is abundantly clear from the records generally that they were no more than would necessarily be expected and unavoidable in this particular activity."

4. This led to his Honour's conclusion in [250] that the appellant had failed to establish that the respondent was in breach of the duty of care owed to him as its employee.

5. The grounds of appeal challenged his Honour's conclusion at [249] that the respondent had in place an appropriate maintenance and supervision system to respond to the environment at the underground mine site.  In my opinion his Honour did not err in this respect. 

6. Another part of ground 13 alleges that his Honour's finding was not reasonably open to him on the evidence.  There is then particularisation of a number of matters.  There was an allegation that there was evidence that no road base material was purchased in certain months and this was then illustrated on a schedule handed up in the form of an aide‑mémoire to this Court.  However, that ignored other evidence that road base material was manufactured on site, and that fact that none was purchased in certain months did not prove that there was no road base material to repair potholes.  The selection of the documentary evidence to show that the roads were not in good repair and the evidence of the appellant was not supported by the overwhelming weight of other evidence given by witnesses who said that the roads were in good condition.  The particulars concerning the seats are very generalised and the evidence that I have referred to does not support the allegation of breach of duty.  Ground 14 contains a generalised assertion and generalised particulars asserting a failure to maintain the roads and seats.  For the reasons already given, those allegations cannot be made out in the face of the evidence to the contrary.  As a result, the allegation that his Honour erred in finding that there was no breach of duty must fail and grounds 13 and 14 must be dismissed.

7. All the other grounds related to the issue of causation.  This was doubtless a very difficult issue because the appellant, on the evidence of the neurosurgeons who had treated him, had a pre‑existing defect in his back.  Mr Woodland described this as a pre‑existing condition of bilateral lumbar 5 pars interarticularis defects with a mild degree of spondylolisthesis (slippage) at the L5/S1 level, and that 5%‑8% of the adult population in this country would have the condition of pars interarticularis defects with a subgroup having developed the slippage/spondylolisthesis.  Mr Woodland said that the condition was not necessarily symptomatic and could be rendered symptomatic by a single incident, sometimes very slight, so that merely twisting and picking something up off the floor can produce a facit joint disturbance.  There was also a significant sequestrated disc fragment at the L3/4 level. 

8. When the appellant collapsed in early January 2000, he was not at work and had not been at work for some 10 days.  22 October 1999, which is the date identified by the appellant as the date when he suffered the work injury, was a day on which there was no particular event leading to the onset of some pain which he noticed at work which caused more pain when he arrived at home and some continuing pain, but no leg pain (the lack of leg pain being significant) until his collapse in January 2000. 

9. On 22 October 1999 the appellant was working the bogger B15, sometimes driving the unit and sometimes working it using remote control.  It is therefore possible that some twisting or bending movement at work on 22 October may have induced the injury or it may, according to the appellant, have been caused by the fact that he was bounced around in his seat while driving on site seated on poor seats and driving on bad roads.  His allegations that there were roads and seats in poor condition amounting to a breach of duty failed, but I am considering the causation issue on the basis that I am wrong in relation to the breach of duty issue.

10. The existence of possible causes, only one of which was the cause associated with the allegations of negligence, means that the appellant must fail.    It was not enough for the appellant to prove that his back pain began at work on 22 October 1999.  If his injury was induced by bending at work, his case failed.  If caused by the defective seats or roads then he had a foundation for his case.  There was no incident at work which caused the sudden onset of pain.  The fact that it was sudden strongly suggests that some slight movement (which might have occurred at home) brought on the disc prolapse.  The evidence left open the possibility that the prolapse did not occur until January 2000.  This was particularly so because he suffered no leg pain.

11. In my opinion, this is a case where expert evidence was necessary to reach a conclusion, even though it is true that it is not always necessary for an expert witness to support allegations of negligence (but bearing in mind that it is not for the expert witness to answer the ultimate question which the court has to answer about causation).  See for example Dahl v Grice [1981] VR 513 at 514. The fact that a causal connection may be open without any medical evidence to support it is uncontroversial. See Fernandez v Tubemakers of Australia Ltd [1975] 2 NSWLR 190 at 197. However, where the court cannot draw a conclusion about which of competing causes might have caused the injury, an expert opinion will often be necessary to assist the court in reaching a conclusion. In those circumstances, the observations of Lord Bridge in Wilsher v Essex Area Health Authority [1988] 2 WLR 557 at 570 ‑ 571 are pertinent. His Lordship said:

    "Where expert witnesses are radically at issue about complex technical questions within their own field and are examined and cross‑examined at length about their conflicting theories, I believe that the Judge's advantage in seeing and hearing them is scarcely less important than when he was to resolve some conflict of primary fact between lay witnesses in purely mundane matters."

12. Further, if the possible cause does not rise above being one of several possibilities, then the plaintiff must fail, as did the plaintiff in Wilsher's case.  His Honour in this case accepted the evidence of Mr Schaeffer, who was an experienced neurosurgeon.  The evidence of Mr Schaeffer was that trauma was unlikely to have caused the injury, and that the most probable cause of the appellant's injury was degenerative disc disease.  Mr Stokes and Mr Woodland, two treating neurosurgeons, were inclined to the view that his back condition was related to some event on 22 October 1999.  The difficulty for the appellant is that they were relying on the account given to them by the appellant, and his Honour did not accept the appellant's description of the amount of bouncing around he suffered.  The further difficulty is that there was no particular incident on 22 October which could be identified.  In my opinion, the grounds of appeal complaining about the trial Judge's conclusion that appellant had not proved that "any work activity the responsibility of the defendant" was "causative" must be dismissed. 

13. A number of grounds of appeal referred to "whole body vibration" having caused the injury.  It is obvious, however, that "whole body vibration" means vibration experienced by a person at a particular level.  Mr Gibson, who referred to the concept of "whole body vibration", carried out no tests on site to say whether or not the injuries suffered were consistent with published material on the subject.  Mr Schaeffer had not heard of "whole body vibration", and the two other neurosurgeons, although they had heard of the expression, did not offer "whole body

vibration" as the cause of the injury.  The trial Judge did not err in accepting and acting on Mr Schaeffer's evidence.

1. The appeal should be dismissed.  

2. BUSS JA:  The appellant appeals to this Court against a judgment of Wisbey DCJ.  After a trial in the District Court, his Honour dismissed the appellant's action for damages for personal injuries allegedly suffered in the course of his employment with the respondent.

3. The appellant alleged that between 1 February 1998 and 23 December 1999 (and especially on 22 October 1999), while driving haul trucks and boggers, he was subjected to frequent jolts, jerking and vibration, which caused injuries to his thoracic, lumbar and sacral spine.   The appellant contended that the respondent, his employer, was negligent in that the trucks and boggers had defective seating, and the roads on which he was required to drive them were not maintained adequately.

4. The learned Judge found that the appellant had suffered serious injuries to his spine, but was not satisfied that those injuries were caused or contributed to by the working conditions of which he complained.  His Honour found, relevantly:

   (a)At [239]:

   "The evidence does not establish what caused the injuries to the [appellant's] back.  Clearly he had a degenerative spinal condition and I am satisfied that something occurred on 22 October 1999 setting in train a course of events culminating in the L3/4 and L5/S1 prolapses.  It is not possible to determine on the evidence whether what occurred on 22 October 1999 was a spontaneous occurrence or the manifestation of some traumatic event.  Since the [appellant] cannot recall a specific event, the state of the evidence is such that a choice between the two is a matter of mere conjecture.  I am, however, unable on the evidence to conclude on the balance of probability that any work activity the responsibility of the [respondent] can be identified as causative.  Indeed in his final submissions [the appellant's] counsel resiled from attempting to attribute responsibility to a specific event occurring on 22 October 1999."

   (b)At [250]:

"The [appellant] has failed to establish that the [respondent] was in breach of the duty of care owed to him as its employee."

1. The learned Judge made a provisional assessment of damages, however, in the sum of $876,477.56, before the deduction of any workers' compensation statutory allowances.

The statement of claim

1. The appellant, in his amended substituted statement of claim, pleaded, relevantly:

   " … 

   2The [respondent]

   (i)is and was at all material times a proprietary limited company registered and incorporated in Australia according to law;

   (ii)at all material times conducted the business of mining;

   (iii)employed the [appellant] from about September 1994 to about 23 December 1999 as a Plant Operator and Truck Driver at the Golden Pig Mine near Southern Cross ('the first mine') and occasionally at the Fraser's Decline Mine near Southern Cross ('the second mine');

   (iv)at all material times occupied, controlled and managed the said mines and the access roads, haulage roads, access ramps and ore drives ('the roads') at the said mines;

   (v)at all material times occupied, controlled and managed the waste pads, resample pads and dumping areas ('the terrain') at and surrounding the mines; and

   (vi)at all material times owned and operated numerous machines including boggers and trucks at and surrounding the mines.

   3At all material times:

   (i)The roads at the said mines were defective.

   Particulars of Defects:

   (a)the roads were not gravelled adequately or at all;

   (b)the roads did not have adequate drains with resultant flooding and deterioration;

   (c)the roads were ungraded; and

   (d)the roads were potholed, corrugated and uneven.

   (ii)The terrain at and surrounding the said mines was defective.

   Particulars of Defects:

   (a)there were numerous steps and pot holes in the terrain; and

   (b)the terrain had not been, or had not been adequately or regularly, levelled by a bulldozer or excavator so as to minimise the impact to truck drivers and machinery operators who were required to travel in machines over the terrain in the course of their employment with the [respondent].

   4At all material times it was an implied term of the contract of employment between the [appellant] and the [respondent] that the [respondent] would exercise reasonable care to provide the [appellant] with:

   (i)a safe system of work;

   (ii)a safe place of work;

   (iii)safe plant and equipment; and

   (iv)adequate instructions, training and warnings;

   so as to guard against the risk that he may be injured in the course of his employment.

   5At all material times by reason of sections 9(1) and 13(1) of the Mines Safety and Inspection Act 1994 (WA) it was the statutory duty of the [respondent] to, so far as was practicable, provide and maintain at the first mine and the second mine a working environment in which the [appellant] was not exposed to hazards.

   6(i)        Between 1 February 1998 and 23 December 1999 at and around the first mine and the second mine and in the course of his said employment with the [respondent] the [appellant] repeatedly and frequently drove haul trucks ('the trucks') and loaders (hereafter referred to as 'boggers') over the said roads and terrain in circumstances where he was subjected to repeated and frequent jolts, jerking and vibration whilst so driving.

   (ii)In most weeks throughout the period pleaded in paragraph 6(i) hereof the [appellant] drove the trucks or the boggers for 5 or 6 days per week and for 6 hours or more per day except for holidays.

   (iii)A number (T6, T9, B13, B15 and B20) of the trucks and boggers so driven by the [appellant] were fitted with defective seats.

   Particulars of Defects:

   (a)the suspension and shock absorbing mechanisms were seized, broken and/or collapsed;

   (b)the adjusting mechanisms were broken and/or not functional;

   (c)the seats had inadequate suspension and/or inadequate shock absorbing mechanisms suitable for use in mining conditions to reduce vibration transmission;

   (d)the seating and suspension systems were not adequately or regularly maintained, repaired and/or replaced; and

   (e)the [appellant's] spine was thereby frequently and repetitively subjected to jolts, jerking and vibration with resultant risk of injury.

   7On or about the 22 October 1999 at the first mine and in the course of his employment with the [respondent]:

   (i)the [appellant] was driving a Caterpillar Elphinstone 1500 bogger known as 'B15' ('the bogger') over roads situated in the C6 and L6 S levels at the first mine.

   (ii)The seat in the bogger was defective.

   Particulars of Defects:

   (a)the suspension and shock absorbing mechanism was seized, broken and/or collapsed;

   (b)the seat had inadequate suspension and/or inadequate shock absorbing mechanisms suitable for use in mining conditions;

   (c)the seating and suspension system was not adequately or regularly maintained, repaired and/or replaced; and

   (d)the [appellant's] spine was thereby frequently and repetitively subjected to jolts, jerking and vibration with resultant risk of injury.

   (iii)The roads pleaded in paragraph 7(i) hereof were defective.

   Particulars:

   The [appellant] repeats and relies upon the Particulars pleaded in paragraph 3 hereof and says further that there were numerous steps in the road in the L6 S level of the first mine.

   (iv)The [appellant] was thereby subjected to frequent and repetitive jolting, jarring, jerking and vibration whilst so driving the bogger with resultant risk of injury.

   8By reason of the matters pleaded in paragraphs 3, 6 and 7 hereof the [appellant] suffered pain and injury.

   Particulars of Injuries:

   (a)Prolapse of the L3, L4 discs with associated nerve root impingement;

   (b)Damage at the L5/S1 level with associated nerve root impingement;

   (c)Tears and bulges along the spine between the L3 and S1 levels;

   (d)Injury to the lumbar and thoracic spine generally;

   (e)Resultant right limb radicular symptoms; and

   (f)Resultant depressive illness and psychiatric disorder.

   9The [appellant's] pain and injuries as pleaded aforesaid were caused by the negligence and/or breach of statutory duty and/or breach of the contract of employment of the [respondent], its servants or agents.

   Particulars of Negligence:

   The [respondent], its servants or agents were negligent in that they:

   (i)provided the [appellant] with defective seating in the trucks and boggers particulars of which are set out in paragraphs 6(iii) and 7(ii) hereof;

   (ii)failed to adequately surface the roads and terrain of the said mines, particulars of which are set out in paragraphs 3 and 7(iii) hereof, so as to reduce vibration transmission to drivers of machinery;

   (iii)failed to provide, repair or replace the seating and suspension in the trucks and boggers with a KAB 515/525 seat and suspension system suitable for use in mining conditions in order to protect the [appellant's] body against frequent and repetitive jolting, jarring, jerking and to reduce vibration transmission;

   (iv)failed properly or at all to supervise the [appellant] in the performance of his work duties whereby the inadequacies and/or dangers of the seat and suspension mechanism and the excessive jolting, jarring and vibration of the boggers and the trucks should have been observed and remedied and the risk of injury to the [appellant] averted;

   (v)failed to take reasonable measures namely ensuring vehicle seating was functional and not defective, by adequately surfacing roads and terrain and by responding to complaints from employees about such matters so as to ensure that the place where the [appellant] carried out his work was safe;

   (vi)failed to provide and maintain a safe system of work for the [appellant]; and

   (vii)failed to heed or to respond to complaints by the [appellant] and other employees of the [respondent] concerning the seating in the trucks and the boggers and the condition of the road and terrain surfaces.

   Particulars of Complaints:

   (a)the [appellant] did on numerous occasions between early 1998 and in or around June 1999 make verbal and written complaints regarding the condition of the roads and/or the seats with the verbal complaints being made to the following persons:  L Giles, B Bosenberg, J Leeder, S Gillman, G Gillman and J Gillman;

   (b)the [appellant] did on or around 24 June 1999 make a complaint to Mines Inspector, R Leggorini, regarding the condition of the roads and terrain;

   (c)written complaints regarding the seating in T6 were made and recorded by employees of the [respondent] on the PLODS sheets on the following occasions:

   M Gorfin ‑ 29 March 1999; W Conway ‑ 29 March 1999; W Horner ‑ 6 April 1999; G Western ‑ 26 June 1999 and 28 June 1999; W Saba ‑ 28 June 1999;

   (d)written complaints regarding the seating in T9 were made on the PLODS sheets by the [appellant] on 4 June 1999 and by G Western on 16 June 1999, 17 June 1999 and 14 July 1999 and were also recorded in the service sheets on 9 November 1998 and 3 November 1999;

   (e)written complaints regarding the seating in B13 were made by other employees of the [respondent] on the PLODS sheets by G Savage on 11 October 1999, 2 December 1999, 4 January 2000 and 5 January 2000 and by G Western on 4 January 2000;

   (f)written complaints regarding the seating in B15 were made by an employee of the [respondent], G McDonald, and were recorded on the PLODS sheets on 28 August 1999, 29 August 1999 and 3 September 1999;

   (g)written complaints regarding the seating in B20 were made by employees of the [respondent] and were recorded on the PLODS sheets by W Horner on 4 November 1999, 5 November 1999, 9 November 1999 and 6 December 1999 and by M Gorfin on 21 December 1999.

   Particulars of Breach of Statutory Duty:

   The [appellant] repeats and relies upon the Particulars of Negligence pleaded above as constituting particulars of the [respondent's] breach of the statutory duty pleaded in paragraph 5 hereof.

   Particulars of Breach of Contract:

   The [appellant] repeats and relies upon the Particulars of Negligence hereinbefore pleaded as constituting particulars of the [respondent's] breach of the implied terms of the contract of employment pleaded in paragraph 4 hereof.

   … "

1. A "plod" is a form which was completed each working day by each of the respondent's employees at the Golden Pig mine.

The challenge to the learned Judge's findings of fact

1. The appellant, in his grounds of appeal, has attacked, amongst other things, the learned Judge's findings of fact in relation to the expert and non‑expert evidence.  It is therefore necessary to recount, at some length, his Honour's findings in relation to the numerous witnesses called by the appellant and the respondent.

The appellant's evidence

1. The learned Judge recorded, in his reasons, the appellant's evidence in relation to material facts and circumstances:

   "8  The [appellant] stated that at the beginning of the shift a full pre‑start would be undertaken before the truck was driven to the portal and down the incline underground where the incline road branched off in various directions.  The journey from the truck depot to the portal was approximately 800 to 1,000 metres.  Once underground it was necessary to go to the blast face and having scaled or removed any loose rock, water down the area before bogging the mullock.  It was the [appellant's] duty to operate a bogger to fill his haul truck with mullock and then transport the ore to the stockpile.  The distance from the blast face to the position where the haul truck was filled from the bogger varied between 200 to 800 metres.  The [appellant] did eight to nine trips per shift, transporting ore.  The road from the portal underground (the decline road) was composed of rock and dirt but often because of washaways, machinery would be travelling over bare and exposed ridges of rock.  He stated that the bogger operator was responsible for forming the road. 

   9  At the time of the birth of his daughter in September 1997 the [appellant] had several weeks off work and when he had returned the grader operator Harry Watt had become a jumbo operator.  The [appellant] returned as a nipper, with limited truck driving, but by January/February 1998 had returned to full‑time driving duties.  By then the mine access roads were only graded monthly.  Initially mullock was placed on the roads by the bogger operators, and thereafter road base was used on the worst sections of road. 

   10  From mid‑1998 until the cessation of his employment, the [appellant] operated trucks and boggers.  He stated that during this period the above surface road was rough and potholed, as were the underground access roads which were not being maintained to the previous levels.  As a result he stated that as a machinery operator he experienced a shocking ride and would be thrown around the cab all through the shift such that it felt like he was being ripped in half.  'The ride was terrible.  Your [sic] getting thrown all around the place'. 

   11  The roads were in a poor condition throughout 1998 and 1999 because of inadequate supply of road base and a lack of drainage causing the road surfaces to be gouged out by water.  In the result the vehicles were often traversing bare rock.  The pumping system which was required to keep the water off the roads was continually failing, and was not rectified until mid‑1999.  Limited grading was being carried out. 

   12  The [appellant] claimed that for most of 1998 and for periods during 1999 there was no road base on site, and he claimed he raised the issue with all the supervisors, at safety meetings, and noted it on his plods.  He stated that the seats in the trucks were usually broken or seized such that the suspension was inoperative, and claimed that it took weeks or months for seats to be repaired or replaced.  He complained about the condition of the seats to his supervisors Lee Giles and Stan Gillman; the site supervisor Justin Leda; the maintenance supervisor John Gillman; and the fitters; but they took no notice of him.  As a consequence he wrote a really damning plod in October 1998 which he handed to Stan Gillman. 

   13  The [appellant] pointed out that the [respondent] claimed an inability to locate any plods prior to November 1998. 

   14  During 1998 and 1999 the [appellant] operated trucks 6 and 9 and boggers 13, 15 and 20.

   …

   17  The [respondent] held regular safety and toolbox meetings, and safety meeting minutes were kept, although the [appellant] claimed they were not necessarily accurate.  A file containing safety meeting minutes and audits pertaining to roads was received as Exhibit 3.  The [appellant] referred in particular to minutes of a safety meeting held at Golden Pig on 7 April 1999 where it was recorded that he made a request for more road base.  Although he could not be definite the [appellant] stated that the probability was that at that date there had not been any road base available for some months. 

   18  Reference was also made by the [appellant] to the minutes of the safety meeting on 8 September 1999 when it was recorded that more road base was coming.  He claimed that there was no road base then available.  The file documents entitled 'documents pertaining to roads' was received (Exhibit 2). 

   19  The [appellant] stated that his complaints about the lack of road base were met with indifference, and did not result in any improvement of road conditions. 

   20  The [appellant] alleged that he endorsed many of his 1998 plods with complaints about the state of roads, but reduced his complaints in 1999 because Stan Gillman had threatened him with the sack.  It does seem from his evidence, however, that he was of the view that the provision of road base improved in 1999. 

   21  The [appellant's] recollection concerning seating was that the seats in trucks 6 and 9 were only replaced once in his employment; that in bogger 13 once or twice; and he had no recollection of the seat being replaced in boggers 15 or 20.  He stated that the seat in truck 6 was 'pretty stuffed usually' with the result that he got bounced around.  The adjustment tilting mechanism was broken.  He stated that the seats in truck 6 and 9 were not properly maintained during his employment and were the cause of continual complaints.  The seats on boggers 13, 15 and 20 between February 1998 and October 1999 were seized or broken, with the result that there was a complete absence of suspension and the [appellant] as driver or operator got shot around 'like a bullet out of a gun'. 

   22  On 22 October 1999 the [appellant] was operating bogger 15 on afternoon shift.  The condition of the roads was pretty bad because of surface water and a lack of road base.  The ride was shocking, the [appellant] claiming to having been thrown about the cab, with the seatbelt cutting him in half.  It was a Friday afternoon.  The [appellant] stated: 

   'As I commenced doing my job my back became sore.  As the shift got on to near the end of the shift I was in quite a lot of pain but as you’re underground you're very warm and you also wear a belt, a big belt, and that keeps your lower back warm.  At the end of the shift as its 11.30 at night I took my belt off and I walked home because the house was near the mine as I cooled down it became extremely painful … my lower back.' 

   23  The [appellant] stated that on arriving home he told his wife that his back was sore, and had a shower.  He went to work the following morning, but claimed that he tried to stay on the truck so that he could brace himself.  Notwithstanding, his back pain worsened as the day progressed.  The [appellant] was unable to recall a specific incident giving rise to his back pain, stating 'I mean when you're getting thrown around the bogger and the truck all the time its hard to describe one from the other, its just the job.  You're getting thrown around because of the roads'. 

   24  When he got home from work on 23 October the [appellant] stated that he lay down on a couch under the patio and when he went to get up his back gave way and he collapsed to the ground.  He spent the rest of that day and the next day, which was Sunday, flat on his back, ingested some analgesics purchased by his wife, and applied inflammatory cream.  He did not work on the Monday because he had his supervisor's exam. 

   25  When he attended work on Tuesday he reported to the site manager, Justin Leda, advising that he had hurt his back and was taking pain killers.  He requested that he be restricted to truck driving, and although that was arranged, his back was extremely sore.  Mr Slater, a chiropractor he consulted in Merredin on Friday, arranged x‑rays and performed a massage and manipulation.  The [appellant's] recollection was that he attended Mr Slater on about four occasions up to 23 December when the mine shut for the Christmas break.  At that stage the [appellant] believed that he had pulled a muscle in his back as he could not recall any specific incident.  Notwithstanding that he worked consistently between 22 October and 23 December, the [appellant] stated that he experienced continuous back pain. 

   26  During the Christmas break the [appellant] went to stay with his in‑laws in Baldivis, and on their recommendation attended a naturopath who massaged his back and applied magnets.  As with the chiropractic treatment, this did not improve his back condition, and he continued to experience constant pain.  On the evening of 1 January 2000 the back pain became so intense that he was unable to sleep or to straighten up in the morning, and he had to be assisted to walk.  He attended upon Dr Loeffler at the Grange Medical Centre and by the time of the appointment he had a loss of sensation in the right leg.  Dr Loeffler gave him an epidural injection so that he could straighten up, but it did not have any effect on the leg condition. 

   27  In January the [appellant] returned to Southern Cross and saw his general practitioner, Dr Leanne Lip, who referred him to the neurosurgeons, Mr Wong and Mr Stokes.  She also prescribed analgesics.  Both neurosurgeons recommended conservative treatment, principally the ingestion of Panadeine Forte and Brufen.  Mr Stokes referred the [appellant] to a spinal surgeon, Mr Woodland, who having assessed him, performed a spinal fusion at the L5/S1 level.  The [appellant] was hospitalised for eight or nine days and following discharge had physiotherapy for approximately a month before ceasing when the insurer stopped payment.

   … 

   33  The [appellant] stated that he made frequent complaints about the state of the mine roads and vehicle seating at toolbox meetings, but without consequence. 

   34  In cross‑examination the [appellant] confirmed he did not recall injuring his back in any specific incident at work.  He said that if he had been told that the jolting of the machinery might cause an injury to his back he would not have taken the job.  When questioned about the circumstances of his injury he stated 'I didn't relate it to anything because I didn't know how I had done it'.  He claimed to have been bounced around violently on just about every shift between January 1998 and December 1999 but continued because 'that was the job'.  He confirmed that he had made complaints about vehicle seats and road conditions to numerous of the [respondent's] employees.  He stated that he endorsed seat complaints in a plod on one or two occasions in 1999, and complaints concerning lack of road base on two or three plods.  Additionally he made numerous verbal complaints.

   35  When it was suggested to the [appellant] that the safety meeting minutes did not record continual complaints by him he stated that the minutes were biased in favour of the [respondent].  He denied that unserviceable seats could be replaced within 24 hours, and although he agreed that it was possible to tag out machinery if it was unsafe, stated that it did not necessarily mean that the machine would be taken out of service.  A schedule of the minutes of the safety meetings and the minutes themselves were received in evidence (Exhibit 5.1 & 2). 

   36  The [appellant] agreed that at an induction in 1994 he was instructed to drive mine vehicles at a speed appropriate to the road conditions, and that it was a matter of commonsense in any event.  Although he agreed that one should drive to the conditions, he claimed that it was necessary to go full tilt so that the hydraulics would operate.  A diesel operator assessment safety questionnaire completed by the [appellant] on 22 November 1994 was received in evidence (Exhibit 6).  An induction questionnaire completed by the [appellant] on 11 March 1996 was received in evidence (Exhibit 7). 

   37  The [appellant] agreed that the bogger operator was required to smooth the road but stated that it was not possible to do so if there was too much surface water.  He asserted that Golden Pig was a wet mine, especially through the A level.  He agreed there was an obligation to tag out unsafe equipment but responded that if an employee started tagging out equipment his conduct would not be viewed favourably. 

   38  The [appellant] stated that he had not been subject to jolting before 1998 as the roads were maintained and seats repaired.  He stated that the bogger operator's job was to maintain the road at the heading or ore drive and not the haulage road, and it appeared from his evidence that the preparation of the road surface in the ore drive would of itself involve the driver of the machinery in significant jolting. 

   39  The [appellant] stated that shifts were of eight hours duration, and claimed that he would be in the seat driving for approximately seven of the eight hours. 

   40  He confirmed that if a vehicle was unserviceable the operator could tag it out and use another vehicle if one was available.  He specifically denied that he had not complained to Lee Giles, Stan Gillman and Justin Leda about the condition of seats in the vehicles, and stated that he also complained to maintenance fitters. 

   41  When discussing the damning plod that he claimed to have handed to Stan Gillman in October 1998 the [appellant] said he had endorsed on it 'failure to rectify unsafe seats and any injury that could happen because of this could result in legal action'.  He agreed that the only written complaint he made about seats during 1999 was on 4 June, and it appears that at that time he changed vehicles.  He stated that he made a complaint to the fitters about too much air pressure in vehicle tyres. 

   42  The [appellant's] recollection was that Stan and Greg Gillman and Justin Leda told him he had an attitude problem. 

   43  He agreed that on 22 October 1999 when he first experienced back pain he had been operating bogger 15 and a truck.  He had been using a remote control for part of the shift and this involved him continually getting in and out of the bogger.  The plod for 22 October 1999 relating to the [appellant's] work was tendered (Exhibit 8) and the [appellant] was prepared to accept that it demonstrated that he would have spent considerably less time seated in the bogger than normally. 

   44  Having been referred to the plods to refresh his memory, the [appellant] agreed that he had operated boggers frequently between 27 October 1999 and 23 December 1999.  When the [appellant] visited the naturopath in Warnbro he received a light massage to his back.  The pain he experienced on 1 January 2000 was described as an extreme version of that experienced on 22 October 1999 although the [appellant] had never before experienced twisting to the right or loss of sensation in the right leg. 

   … 

   46  In re‑examination the [appellant] stated that if he had tagged out a machine because of the condition of the seat he would have lost his job, but stated that he had tagged out machines for other reasons."

The evidence of the appellant's wife, Joanne Robertson

1. The learned Judge recounted, at [49], the evidence of the appellant's wife, Joanne Robertson, in relation to the incident on 22 October 1999:

   "Mrs Robertson stated that on 22 October 1999 the [appellant] complained of a really sore back when he came home from work.  His position was worse the following day, causing him to lie down on a couch under the verandah where he 'sort of collapsed'.  That incident was on a Saturday and the [appellant] lay around on the weekend.  Although the [appellant] returned to work between that time and Christmas he was experiencing continuous pain and attended a chiropractor."

The evidence of Dr Ian Gibson

1. Dr Ian Gibson is a consultant ergonomist who was called by the appellant.  He holds the degree of doctor of philosophy in human physiology and has undertaken post‑graduate research in that discipline.  In a report dated 9 September 2003, which was tendered in evidence, Dr Gibson refers to a phenomenon known as "whole‑body vibration".  In his report, Dr Gibson states, relevantly:

   " … 

   2.2Accident details

   2.2.1Mr Robertson has not identified any single event as the cause of his back problems.  Back pain developed at the end of a routine shift on 22 October 1999 and I note that Mr Robertson continued working until January 2000 when increasing pain forced him to cease work.  The medical reports describe Mr Robertson's subsequent treatment, which is not relevant to this report, save to note that Dr Woodland's report links Mr Robertson's back injury to his conditions of work.

   2.2.2Mr Robertson believes that driving the bogger was physically more stressful than driving the truck because of the difference in seating positions ‑ in the bogger the driver sits facing across the vehicle and has to continuously turn his head from left to right in order to manoeuvre the vehicle, and cannot avoid rough sections of road, whereas in the truck he is facing forward with a better view of the road surface and can brace himself when traversing rough sections.

   3.0REVIEW OF RISK FACTORS

   3.1Vibration and its effects

   3.1.1Whole‑body vibration (WBV) is where vibration is transmitted to the body as a whole by its supporting surface (ie seat or floor).  It is commonly experienced in the mining industry by drivers, operators and passengers in a variety of vehicles, including load‑haul‑dump (LHD) machines and boggers, such as those operated by Mr Robertson.

   3.1.2WBV is believed to cause a range of problems, especially those affecting the musculoskeletal system for the lower back.  These disorders are believed to arise from damage to the spine and surrounding structures brought about by an accumulation of strains placed on the back over a period of time, and rarely a single event.

   3.1.3In addition to vibration, other components of work may be risk factors for back disorders, such as:  heavy physical work, sustained static postures, frequent bending and twisting of the trunk, repetitive lifting and forceful movements.  Many people will suffer back pain in the absence of significant exposure to vibration, but the consensus of ergonomic and medical opinion is that WBV can make a substantial contribution to the development of disorders of the lower back.

   3.2Sources of vibration

   3.2.1There are three main sources of vibration which are transmitted to the driver via the seat pan, namely road surface, vehicle activity (speed, type of task, load) and engine vibration.  Rough roads are a major source of harmful vibration, and it is always important to maintain a road surface in the best possible condition so as to minimise wear and tear on both equipment and operators. … 

   3.2.2Other important factors influencing a driver's exposure to vibration are the state of the vehicle (age, condition, suspension), the seat (design, suspension, maintenance), cab layout, work organisation (especially shift duration).  Thus many factors can increase or decrease a driver's exposure to vibration.

   3.2.3Poor road conditions will expose the driver to a high level of vibration on which will be superimposed sudden jolts and jars from pot holes or ridges.

   3.2.4A good quality suspension seat can significantly reduce the intensity of the vibration reaching the driver, although it can never be 100% effective.  Seat suspension systems deteriorate over time, especially under harsh conditions, and if not maintained or replaced can add to vibration problems. … "

1. Dr Gibson admitted, in cross‑examination, that he had not carried out any calculations as to the vibration levels in haul trucks and boggers of the kind driven by the appellant in the conditions in which he operated.

The evidence of Mr Bryant Stokes

1. Mr Bryant Stokes is a consultant neurosurgeon who was called by the appellant.  He examined the appellant on 27 January 2000 and diagnosed spondylolisthesis of L5/S1 and disc protrusions of his lumbar spine at L3/4 and L5/S1.  In a report dated 27 January 2000, which was tendered in evidence, Mr Stokes said, relevantly:

   "Mr. Robertson explained that he had the slow onset of low back pain in October 1999 without any evidence of an acute injury that could have produced these symptoms however, he believes, and I would support this view, that he has constant jolting in his work driving dump trucks and boggers and that certainly can produce a repetitive stress injury to the lumbar spine.

   This man's history does not give an account of any other injury that could have caused his symptoms and therefore one could consider that the persistence of repetitive strain to his back could have been the cause of the current situation.  What is significant is that on return to work his symptoms were grossly magnified and causing him to cease work early in January to which he has not yet returned.  He has a spondylolisthesis at L5 on S1 and this is likely to be congenital and not directly caused by the work but could have been made symptomatic by repetitive jolting and stress to the lumbar spine."

2. The learned Judge summarised, at [67] ‑ [69], Mr Stokes' evidence at trial, relevantly, as follows:

   "Mr Stokes when given the history of the incapacitating incident on the night of 1 January 2000 and asked to comment on it stated: 

   'Well it does seem as though something did occur.  Now one of the common things that occur is that where there is any form of disc degenerative change or degenerative change in the back that there can be what's called facet joint disturbance and that can occur very simply.  I mean many of us experience these things from time to time.  Just simply twisting and picking something up off the floor can produce a facet joint disturbance.  And that can produce acute pain?‑‑‑Absolutely.' 

   Mr Stokes stated that it was his view that there was a lot of low frequency but high amplitude jolting in operating mining machinery and that the seating position on a bogger was also a factor. 

   Mr Stokes confirmed that he assessed the [appellant's] disability as of the order of 25 per cent, but that assessment was pre‑spinal fusion, and he had not seen the [appellant] since 2001.  It was clear that Mr Stokes attributed the [appellant's] continuing back pain to the spondylolisthesis at L5/S1.  It appeared from Mr Stokes' evidence that the relationship of spinal injury and/or symptoms, to vibration, had not been comprehensively evaluated."

The evidence of Mr Peter Woodland

1. Mr Peter Woodland is an orthopaedic surgeon, who specialises in spinal surgery, and was called by the appellant.

2. In a report dated 13 January 2003, which was tendered in evidence, Mr Woodland states, relevantly:

   "The first point I would make is that your client informed me on my initial assessment 30 July 2001 that prior to the incident 22 October 1999 he did not experience any significant lumbar back pain and that statement is also indicated in your letter.  The other point is that there is no doubt in my mind that your client did have the pre‑existing condition of bilateral lumbar 5 pars interarticularis defects with a mild degree of spondylolisthesis (slippage) at the L5/S1 level.  5% ‑ 8% of the adult population in this country would have the condition of pars interarticularis defects with a sub group having developed the slippage/spondylolisthesis.  The condition however is not necessarily symptomatic.  One has to say however, that this condition does predispose to an individual's development of back pain and it is my strong view that the condition can be rendered symptomatic by repetitive incidents or a single incident.

   In your client's case it is my view that taking into account he denied any significant pre‑existing back symptoms, the incident on 22 October 1999 when your client was operating the Bogger in the mine was the principal cause of his injuries.  I certainly agree that his work history in the preceding years involved operating machinery over rough terrain and I would not have been surprised if a worker with the pre‑existing condition of pars defects and spondylolisthesis would have experienced back pain, but again your client reports that he did not experience significant pain prior to the incident 22 October 1999.

   The initial lumbar spine MRI scan 28 January 2000 did show also a significant disc protrusion at the L3/4 level extending to the right hand side and I personally feel that your client's initial severe pain dating to 22 October 1999 was probably due to a combination of disc injury at the L3/4 level and also due to the L5/S1 spondylolisthesis being rendered symptomatic.  As you would be aware, follow‑up MRI scan 13 November 2000, 10 months later, showed almost complete resolution of the previous large L3/4 disc protrusion.  By the time I first saw your client July 2001 there was no doubt in my mind that his lumbar back pain and reported right lower limb sciatic symptoms related to the L5/S1 spondylolisthesis with right side L5 nerve root impingement.  The diagnostic test of discography performed by Dr Michael Kent, Pain Management Specialist also had confirmed that the pain generator was likely to be the L5/S1 disc and motion segment level.

   The fact that there was a large L3/4 disc protrusion which subsequently resolved over the ensuing months, does strongly suggest that there was a specific incident on or about 22 October 1999, that is there was some acute event significant enough to cause disc injury."

   Mr Woodland also noted that the significant ongoing jarring and jolting to the appellant's lumbar spine in the course of his employment may have caused increased wear and tear and degenerative change, at both the L3/4 disc level and the L5/S1 spondylolisthesis level.  Mr Woodland then recorded that although the appellant did not apparently experience any back pain until October 1999, "one could argue that the pre‑existing work conditions resulting in increased wear and tear did pre‑dispose to acute injury occurring on or about 22 October 1999".  Although Mr Woodland found it extremely difficult to quantify exactly, he suggested that "25% of [the appellant's] injury causation related to the driving conditions in the months or years preceding 22 October 1999".

3. Mr Woodland, in his oral evidence, explained (at T216) the nature of spondylolisthesis:

   " … there's an inherent weakness at the base of the spine.  Instead of one solid bone, the bottom L5 vertebra is split in two and that develops at an early age, probably in late childhood, and your back is just not as strong at that level ..."

4. The learned Judge summarised, at [84] ‑ [85], Mr Woodland's oral evidence, relevantly, as follows:

   " … When questioned specifically on causation, Mr Woodland referred to the disc protrusion at the L3/4 level, and the L5/S1 spondylolisthesis, and in respect to the latter noted that a person with that condition who was exposed to a single event injury or multiple repetitive injuries could develop back pain because of the inherent weakness at the base of the spine.  He was satisfied that as at January 2000 the [appellant] had an acute disc protrusion ‑ that something happened.  As he put it 'it was  a pre‑existing condition of spondylolisthesis at the L5/S1 level and that was rendered symptomatic by whatever cause'. 

   Mr Woodland stated that as at 8 November 2001 when he operated, the L3/4 disc protrusion had subsided such that most if not all of the [appellant's] ongoing back pain originated from the L5/S1 level. … He expressed the view that 80 per cent of adults develop back pain, and that people with a spondylolisthesis are more likely to experience back pain than those without the condition.  He stated that there was anecdotal evidence that if the spine was subject to excessive vibration it led to an acceleration of degenerative change."

The evidence of Dr Andrew Harper

1. Dr Andrew Harper is a specialist occupational physician who was called by the appellant.

2. In a report dated 6 December 2000, which was tendered in evidence, Dr Harper recorded that the appellant informed him that he first developed low back pain on 22 October 1999.  The pain came on gradually after work, following a normal day's work and the symptoms worsened the next day.  The appellant continued to work until Christmas 1999, and on 2 January 2000 awoke at night with extreme pain in the lower back and a loss of feeling in the right leg.  He had not previously experienced any difficulties with his spine.

3. In his evidence at trial, Dr Harper expressed the opinion that repetitive jarring and vibration is a factor in causing disc and spinal degeneration.

The evidence of Dr Michael Kent

1. Dr Michael Kent is an anaesthetist and consultant pain management specialist who was called by the appellant.  In a report dated 9 August 2001, which was tendered in evidence, Dr Kent said:

   "Mr Robertson presented to me a confusing picture.  I think his original symptomatology was in fact due to the L3/4 disc prolapse and sequestration of disc fragment, causing an L4 radiculopathy.  There is at least radiographic evidence of resolution in large part of this abnormality.  I think his current pain relates to the L5/S1 motion segment and discography would suggest that the L5/S1 disc is the most likely pain generator at this time."

   The learned Judge recorded, at [106] ‑ [108], evidence which Dr Kent gave at trial:

   "In the course of his evidence he confirmed that although an early MRI scan showed an L3/4 disc prolapse with compression of the right L4 nerve root, when he saw the [appellant] on 22 November 2000 the picture had changed considerably in that in respect of the disc prolapse the disc fragment pressing on the L4 nerve root had been reabsorbed and the back pain seemed referrable to L5/S1.

   Dr Kent stated that a lumbo discography performed on 23 February 2001 demonstrated abnormal discs at L3/4, L4/5 and L5/S1, although the pain seemed to relate to the L5/S1 area. 

   In addressing the issue of the acute presentation on 2 January 2000 Dr Kent said: 

   'The original insult might have resulted in a weakening of the disc and acute pain at the time.  That could have been in October.  It can then settle to one degree or another but the underlying problem still remains.  That can then present days, weeks or months later as an acute disc prolapse and acute nerve root symptoms.  Mr Robertson's history is not incompatible with that scenario.'"

The evidence of Stanley Gillman

1. Stanley Gillman, a director of the respondent, has had significant experience in the mining industry.  The learned Judge set out in his reasons, at length, the substance of Mr Gillman's evidence.  It is useful to reproduce what his Honour said, at [116] ‑ [144]:

   "116  [Mr Gillman] confirmed that road base or crushed rock was spread on the mine road surfaces to provide a final surface, and it was obtained from around the mine or brought in.  He stated that the [respondent] organised a screen deck in about November 1999 to provide its own supply of road base.  Generally road base was taken underground by the bogger operators, and the decision as to when to take and spread more road base seemed from his evidence to sometimes be left to the bogger operators.  He disagreed with a comment made by the [appellant] that 800 tonnes of road base would be totally inadequate, stating that the Golden Pig roads were of a hard flat surface and consequently did not require copious amounts of road base.  Basically maintenance consisted of filling in the potholes and smoothing off. 

   117  Mr Gillman could not recall the [appellant] ever complaining about the lack of road base.  He was unable to recall any occasions when there was a lack of road base at Golden Pig, although he had no doubt that there were times when it was in short supply.  Mr Gillman explained that the underground roads were formed by the bogger operators, following drilling and blasting in the decline, sheeting up behind as the decline moved forward.  He disagreed strongly with the [appellant's] contention that the roads at Golden Pig were in a woeful condition.  When asked about 'toes', Mr Gillman stated that they were generally located at the drill face and were subsequently eliminated by filling or otherwise as the excavation proceeded.  Pot holes were generally filled.  Although a grader was engaged from time to time, the road maintenance work was often undertaken by the machinery operators.  He stated that the [respondent] had a good induction system and that instructions were given to employees to note on their plods any equipment failures and/or to tag up [sic] defective machinery. 

   118  Mr Gillman could not recall the [appellant] complaining to him about the condition of seats in the machinery.  He denied that the [appellant] handed him a plod in October 1998 in which he made a firm complaint about the condition of a seat in a vehicle, and stated that he had never abused the [appellant] or threatened him with dismissal.  He stated that the [appellant] had good underground skills but there had been an issue in 1999 when the [appellant] made a personal attack concerning the mine foreman. 

   119  Mr Gillman confirmed that the seats in the trucks and boggers were adjustable to meet the particular requirements of the operator.  He stated that if an operator was not satisfied with the condition of the seat [of] a vehicle he could report it on the plod or tag the machine out.  If an operator tagged the machine out, he could park it up because there was generally another machine available.  He claimed that the [respondent] did not have any difficulty with operators tagging out machinery since its policy was to encourage proper maintenance. 

   120  He had no recollection of swearing to a Mr McDonald about the behaviour of the [appellant].  He claimed that the normal changeover period for a defective seat would be 24 hours.  There was an eight man maintenance crew headed by John Gillman, the maintenance supervisor, to deal with defective equipment and machinery, and it was not subject to budgetary restrictions.  There was also a practice of cannibalising parts from machines that were excess to requirements. 

   121  Mr Gillman stated that at the conclusion of a shift it was the practise [sic] of the operator to complete his plod and hand it in to the shift boss who would then bring any maintenance requirements to the attention of the maintenance crew.  He confirmed that the [respondent's] operations resulted in the production of about 200 to 250 plods a week.  Having been dealt with, the plods were archived for a period of time before being destroyed.  As a consequence of reorganisation, all plods in storage prior to January 1999 were incinerated at about that time.  Following a request from the [appellant's] solicitors he searched for the plods covering the period January to October 1998 but could not locate them. 

   122  Mr Gillman could not recall the [appellant] making any specific complaints about the condition of the mine roads in 1998.  He advised that the [respondent's] line of employment authority was that there was a mine foreman, Justin Leda; three shift bosses Lee Giles, Brian Bosenberg and Wayne Conway responsible to Mr Leda; and then the production crew which included the machine operators such as the [appellant]. 

   123  Mr Gillman said that Fraser's mine was a very wet mine and required considerable grading to keep it operational, whereas Golden Pig was a dry mine.  He stated that the roads at Golden Pig were as good as the roads in any of the other mines in which he had worked over 25 years.  It was not possible to get the grader in near the ore drives, and it was the responsibility of the bogger drivers to keep the roadways clean. 

   124  Mr Gillman claimed that the haulage ways were graded on about a weekly or perhaps fortnightly basis in 1988[sic]‑1999.  The grading duties were undertaken by Mr Gillman, his brother Greg, or Harry Watts.  Mr Gillman stated that in an eight hour shift a machinery operator would be in his seat for about six and a half hours.  He stated that there were monthly safety meetings and additionally occupational health meetings attended by all employees.  The machinery was serviced regularly including comprehensive weekly services. 

   125  In cross‑examination Mr Gillman seemed to retreat to the position that grading was not done more regularly than fortnightly.  When asked whether he ever received any complaints about the roads he responded that there would always be problems with road conditions in the underground mining environment.  From time to time the roads would be cut up and require attention.  He asserted that road base was on site most of the time, but there were occasions when it was not available. 

   126  He agreed that the [respondent] was not producing road base until mid‑1999, and prior to that was buying it.  When shown the spread sheet (Exhibit 18) he agreed that it demonstrated the [respondent] did not purchase road base in January, May, September, October, November and December 1998 nor May, July or August of 1999, but notwithstanding he asserted that there was generally sufficient road base available. 

   127  Mr Gillman agreed that Mr Tynan who was engaged by the [respondent] as a safety consultant had reported that roadworks were required throughout the mine, but commented again that it was an ongoing process.  Essentially he seemed unable to make any useful contribution to the condition of the roads at the time of Mr Tynan's report.  He was referred to Mr Tynan's report of 28 January 1999 which contained a further reference 'declines require a lot of road base and need more work cleaning up and grading closer to the working levels'. 

   128  Mr Gillman was referred to the Occupational Health and Safety Committee meeting of 20 May 1998 which referred to the deteriorating state of the roads, and agreed that was indicative of a problem at that time, and that the minutes suggested an ongoing problem.  The minutes of the meeting on 14 July 1998 noted that the L6 north drive under the sublevel access was in atrocious condition and required cleaning.  Mr Gillman stated that was an area that was unable to be graded, and had to be cleaned up by the bogger drivers.  Its significance depended upon when firing occurred as the condition referred to was to be expected immediately after a firing.  He agreed, however, that if the bogger drivers were doing their job the drive should not be in an atrocious condition. 

   129  The safety meeting minutes of 6 May made reference to the fact that roadworks were required in and around the drives, especially in K7 area.  Mr Gillman said that it simply indicated a necessity for the bogger driver to run the bogger bucket along the wall.  He appeared to concede that there were problems experienced from time to time with the ground water pumping arrangements and that he had seen drives where water had washed away the fill, causing corrugations. 

   130  The minutes of 5 August 1998 made reference to flooding, the necessity for grading, and the scarcity of road base.  The spread sheet demonstrated that road base was not purchased in August 1998. 

   131  The minutes for 2 September 1998 again contained reference to Mr Gillman's request that road base be used sparingly.  The spread sheet demonstrated that road base was not purchased in that month. 

   132  The minutes for the meeting of 14 January 1999 recorded that the grading hours in November and December 1998 had reduced significantly.  Road base had not been purchased in November or December 1998, which appeared consistent with that minute, although Mr Gillman pointed out that the roads could still be graded whether or not there was road base, as it was possible to use material in the side windrows.  The minute suggested that the road conditions were causing damage to truck tyres.  Mr Gillman expressed the view that it was probably in the load areas.  He agreed that the provision of road base and road  conditions was a general safety issue, and that he understood that jolting and jarring on rough roads had the potential to result in back injury to machinery operators. 

   133  The minutes of the safety meeting on 7 April 1999 referred to the [appellant] enquiring as to the availability of road base and being advised that it would be available by the end of the week, and that the [respondent] was looking into crushing on site. 

   134  Mr Gillman did not agree that the conclusion to be drawn from the safety meeting references was that there was generally an insufficiency of road base on site, claiming that the supply was adequate to maintain the roads in reasonable condition. 

   135  Mr Gillman agreed that a plod completed by Mr Bosenberg on 21 January 1999 referred to the necessity for roadworks, and that his plod of 12 April 1999 noted that the road was washed out. 

   136  In cross‑examination Mr Gillman agreed that there were references by various employees to the fact that the roadway in certain areas was poor and/or in need of cleaning and attention, but protested that was not an unexpected consequence of mining activities.  He agreed, however, that because of the rough road conditions that would be expected to be encountered from time to time, it was important that the seats in the trucks and boggers were adequate to meet the situation. 

   137  Mr Gillman's plod of 8 August 1999 described the conditions underground at that time as 'shit'. 

   138  Mr Gillman was unable to point to any documentary record that a truck or bogger had been tagged out because of a defective seat between January 1998 and December 1999. 

   139  Mr Gillman was cross‑examined on the spread sheet, and agreed that it demonstrated that in respect of bogger 13 the seat was repaired in June 1998 and there was no indication that it had ever been replaced.  Bogger 15 had seats replaced in January 1998 and December 1999, but there was no indication of any seat repairs.  Truck 6 had replacement seats in April and October 1998 and June 1999, and a seat repair in August 1998.  Truck 9 had seat replacements in April 1998 and December 1999 and seat repairs in May and August 1998 and June and November 1999. 

   140  Mr Gillman stated that if seats had been cannibalised from another machine, however, there would be no record and it would not show up on the spread sheet.  It was put to Mr Gillman that an examination of the plods when compared to the spread sheet suggested that complaints about the condition of seats often did not receive very prompt attention. 

   141  When it was put to him that his evidence that seats were replaced within 24 hours of complaint was incorrect, Mr Gillman responded 'apart from unallocated seats or seats being moved in from the other machines that we had parked up and we were cannibalising, I cannot prove that we were putting the seats in with this proof'. 

   142  Mr Gillman could not recall telling Jeff McDonald that he was 'pissed off' with the [appellant].  Similarly he had no recollection of seeing a plod completed by the [appellant] complaining about a defective seat and suggesting that it might give rise to injury and legal proceedings.  He went further, and denied that it had occurred. 

   143  Mr Gillman was referred to an internal memorandum from Graham Lingard, the mine foreman, dated 26 February 1999 contained in Exhibit 2 noting that the general condition of the underground roads had deteriorated and required prompt attention to bring them up to the required standard.  He stated that he was not in a position to disagree with that assertion. 

   144  In re‑examination Mr Gillman confirmed that as a result of the mining operation there were approximately 96 plods received per week over the 51 working weeks of the year.  He agreed that there was probably something of the order of 10,000 plods that had come into existence, and of those it appeared from the documentation that there were a very small number that asserted problems with seats and/or the condition of roads.  He stated that the spread sheet did not record unallocated seats or seats cannibalised from other vehicles."

The evidence of Dr Steven Chew

1. Dr Steven Chew is a consultant mechanical engineer who was called by the respondent.  The learned Judge summarised his evidence, at [150] ‑ [157]:

   "150  Dr Chew's first report specifically addressed matters raised by Dr Ian Gibson.  He agreed that there was a phenomenon described as whole body vibration (WBV) which was known to cause low back injury brought about by an accumulation of strains over a period of time.  He agreed with the fairly obvious propositions put by Dr Gibson that the three main sources of vibration transmitted to the operator of a vehicle were road surface, vehicle speed, and engine vibration, and that in that respect the condition of the vehicle's suspension and seating were important. 

   151  He reported that whether the driver's seat amplified vibration or attenuated it by damping, depending on the characteristics of the springs and gas strut used.  It was his view that significant testing in the work situation was required before any informed comment could be advanced as to the [appellant's] WBV exposure and the consequences thereof.  He agreed that it was important that vehicle seats be regularly inspected and properly maintained. 

   152  He agreed that literature dating back to the 1980's contained epidemiological and anecdotal evidence linking exposure to WBV with the development of low back pain in drivers and operators of mining equipment. 

   153  In his report of 24 February 2004 Dr Chew recorded that he had inspected the operator work station on an Elphinstone bogger and the operator cab of a Torro 35D dump truck.  The vehicles were located at the [respondent's] Southern Cross operation.  Dr Chew also entered the underground mine to observe the typical tunnel roads and a bogger being operated by remote control. 

   154  He reported that the KAB 301 seat fitted to the bogger had a mechanical torsional bar suspension and a gas strut damper.  A KAB 525 seat had a mechanical torsional bar suspension, two coil springs, and a gas strut damper.  The report concluded that the KAB 525 seat could not be fitted to the bogger and stated generally about its comparison with the KAB 301 seat that: 

   'Whilst the KAB 525 seat, in comparison to the KAB 301 seat, has additional features which are desirable from the ergonomic prospective, namely the adjustable lumbar support and the weight dialler, there is yet no evidence to support the hypothesis that the whole body vibration experienced by an operator of the Elphinstone R1500 bogger fitted with a KAB 301 seat is at harmful levels, nor is there evidence to support the hypothesis that replacing the KAB 301 seat by a KAB 525 seat will reduce the whole body vibration experience by the bogger operator.' 

   155  That assessment related also to the Torro 35D dump truck although it was accepted that the KAB 525 seat could be fitted to the dump truck. 

   156  … 

   157  In cross‑examination Dr Chew agreed that WBV was an accepted risk of injury to drivers of boggers and trucks in the mining industry and was so recognised in the 1990's.  He also agreed that if the mine roads were not maintained to a proper level and/or the vehicles were not properly maintained, the risk was increased.  He made the obvious comment that a mine road would not be or be expected to be as good as roads provided for normal vehicular traffic."

The evidence of Mr Harold Schaeffer

1. Mr Harold Schaeffer is a retired consultant neurosurgeon who was called by the respondent.  He examined the appellant on 15 March 2004, at the respondent's request.  Mr Schaeffer did not treat the appellant's injuries.  The learned Judge summarised Mr Schaeffer's evidence, relevantly, at [167] ‑ [174]:

   "167  Mr Schaeffer reported that the spinal fusion although technically successful, did not appear to have reduced the [appellant's] back pain probably because it was emanating from more than one lumbar level.  He expressed the view that the essential cause of the [appellant's] symptomatology was degenerative disc disease of the mid and lower lumbar spine, the L5/S1 spondylolisthesis having played some part in destabilising the lumbar spine.  He reported that these were constitutional problems and not precipitated traumatically.  He further reported: 

   'Indeed there is no history of any obvious specific injury to the lumbar spine in this case.  He alleges that his symptoms have been caused or precipitated by the jolting and jarring movements while driving machinery at work, but I find it difficult to see how this is something that would have resulted in any actual structural injury to the lumbar spine.  It could, of course, have resulted in some degree of symptomatic aggravation, but I'm not satisfied that it has constituted a significant causal factor in respect of his current disability.  Certainly the underlying degenerative condition and the spondylolisthesis are much more important aetiological factors.' 

   168  Mr Schaeffer summarised his views as follows: 

   'My diagnosis is that of degenerative disc disease of the lower lumbar spine, substantially at the L3/4 and L5/S1 levels and a congenital spondylolisthesis at the L5/S1 level.  There is likely to have been a work related aggravation.' 

   169  … 

   170  In his report of 16 July 2004 Mr Schaeffer seems to take the position that as the surgery was work related, the disability must to some extent be work related, but that apparently because he assumed that there was an injury on 23 [sic] October 1999 during the course of the [appellant's] work, although even then he did not consider that to be a significant causal factor.  He recorded his view that the injury represented a temporary aggravation of the degenerative condition and spondylolisthesis. 

   171  Mr Schaeffer confirmed in evidence the views expressed in his reports, and in particular the view that the events of 22 October 1999 did not constitute anything more than a temporary aggravation of the underlying spinal conditions.  He considered there must have been some advancement in the degenerative condition proximate to 2 January 2000 when the [appellant] experienced an acute onset of pain. 

   172  Mr Schaeffer stated that medical studies demonstrated that in 40 per cent of disc protrusion there was no history of a traumatic event, the protrusion being a spontaneous process because of the reasons which he outlined.  Where the prolapse was precipitated by injury it was usually the result of a bending and/or lifting incident.  Trauma did not cause degeneration.  He stated that he had difficulty accepting that the driving of vehicles played a substantial part in the development of disc herniation, and did not accept that driving resulted in any structural alteration of the appearances of the [appellant's] lumbar spine. 

   173  When asked in cross‑examination to comment on WBV, Mr Schaeffer stated: 

   'Look, back symptoms particularly in middle age are ubiquitous and I'm not surprised that anybody will experience some back symptoms under various circumstances including what you suggest.'

   174  He stated that his experience was that the commonest age group for adults suffering lumbar disc problems was 30 to 40 years.  Pre‑existing degeneration was a prerequisite for disc herniation, but Mr Schaeffer would not accept that driving over rough conditions was likely to accelerate the degenerative process."

The evidence of Dr Alan Home

1. Dr Alan Home is an occupational physician who was called by the respondent.  He examined the appellant on 27 October 2003 and 20 October 2004.  The learned Judge referred, at [177] ‑ [179], to various aspects of Dr Home's evidence at trial:

   "177  In his report of 20 October 2004 Dr Home recorded that the [appellant] continued to describe chronic low back pain predominantly right‑sided without significant pain referral.  In addition he was receiving treatment for depression.  Dr Home felt on examination that the [appellant's] complaints were consistent, and stated that there had not been any significant change in presentation since the first review.  … 

   178  In the course of his evidence Dr Home expressed the view that the acute disc protrusion at L3/4 probably occurred proximate to 2 January 2000 when the [appellant] experienced an acute onset of pain.  As with Mr Schaeffer, he considered that spinal degeneration was a prerequisite to an acute disc protrusion.  … 

   179  In cross‑examination Dr Home stated that the issue of whether exposure to low frequency vibration contributed to degenerative change was controversial although there appeared to be a correlation between driving heavy vehicles and the development of back pain, although even in that respect the studies were equivocal and there was insufficient epidemiological evidence to reach a firm conclusion.  He expressed the view that because the [appellant] was able to drive heavy machinery between 22 October 1999 and 23 December 1999 it was unlikely that he had an acute disc protrusion on 22 October 1999."

The evidence of Peter Tynan

1. Peter Tynan has had about 25 years' experience in the mining industry.  He specialises in the provision of safety and training.  He investigated and reported on the appellant's injury.  At trial, Mr Tynan gave evidence that the appellant had told him that he had no recollection of any specific event causing the development of the pain he experienced on 22 October 1999.  Mr Tynan gave evidence that he had undertaken assessments and prepared safety reports for the respondent.  He said that Golden Pig was fairly typical of underground mining operations of a comparable size.

The evidence of Gregory Gillman

1. Gregory Gillman, a director of the respondent, was the assistant manager of the Golden Pig operations.  He could not recall any problems with the supply of road base at Golden Pig.  He agreed, however, that there were occasions when road base was scarce but, to his recollection, there was always some road base available.  Mr Gillman could not recall any particular problems with the seats of machinery used in underground operations or the condition of the road surface.  The learned Judge found, at [186], that although there was little doubt Mr Gillman was a truthful witness, his evidence generally was vague and uncertain.

The evidence of Wayne Conway

1. Wayne Conway was the respondent's safety officer.  The learned Judge recorded aspects of his evidence, at [187] ‑ [190]:

   "187  … [Mr Conway] pointed out that the [respondent] had a maintenance team headed by a maintenance supervisor which was responsible for checking plods and dealing with any maintenance requirements.  He stated that as a general rule most of the faults reported to maintenance were unrelated to seats.  He stated that the roads were kept in repair by a grader driver, whose task was to do all the main haulage ways.  The bogger operators attended to the ore drives.  It appeared from his evidence that some of the bogger operators were somewhat dilatory in this respect.  He agreed that there were occasions when the [respondent] ran low on road base but stated that the waste or dirt from the ore drives was generally available for road surfacing. 

   188  Mr Conway could not recall the [appellant] complaining about vehicle seats or road conditions.  He confirmed the obvious point that it was necessary to drive to the conditions. 

   189  In cross‑examination he agreed that the [appellant] appeared to adopt safe work practices, although his contact with the [appellant] was somewhat limited in terms of being his shift boss.  Although he could not recall the [appellant] complaining of seats and/or road conditions he agreed that he could not exclude the fact that he did in fact complain.  He agreed that the [respondent] had problems with road base on a few occasions, and it can be inferred that he meant from that that there were times when road base was not available. 

   190  Although asserting that the main haulways were generally well maintained, Mr Conway agreed that there were times when by reason of spillage or other causes the road conditions were not satisfactory for the smooth operation of vehicles.  He agreed that some dewatering problems had been experienced at Golden Pig, but pointed out that it was a harsh environment.  He could not recall any occasion when a seat was tagged out, pointing out that it was the operators [sic] responsibility to tag out a defective seat."

The evidence of Robert Leggerini

1. Robert Leggerini is a mines inspector with the Department of Industry and Resources.  He has held that position for 29 years.  The learned Judge summarised his evidence, at [191] ‑ [192]:

   " … [Mr Leggerini's] job involves visiting all active mine sites within a particular region which included Southern Cross where the Golden Pig operation was conducted.  He stated that he endeavoured to visit underground mine sites at least four times a year and his recollection was that he would have visited Golden Pig approximately four times in 1999.  He stated that it was his practise [sic] to intermingle with the employees, and that from time to time they would make safety issue complaints to him.  He could not recall the [appellant] ever complaining about road conditions or vehicle seats. 

   His report following an inspection of Golden Pig on 23 June 1999 was tendered in evidence (Exhibit 22).  That document indicated that no significance [sic] safety issues were detected on that occasion.  Because he got transferred to the Collie region sometime in 1999 he was unable to confirm that he attended Golden Pig four times during that year.  He also confirmed that the condition of roads on a mine site was in a constant state of flux.  He had a recollection that there was an occasion when he noted water problems in the Golden Pig decline."

The evidence of John Gillman

1. John Gillman is a qualified diesel mechanic.  His recollection was that in 1998 and 1999 he was maintenance supervisor at Golden Pig.  The learned Judge summarised his evidence, at [194] ‑ [201]:

   "194  In respect to maintenance he stated that on each shift there was an underground fitter, a workshop fitter and an apprentice.  At shift changes they would perform daily servicing, greasing, checking vehicles for damage, and dealing with anything the plods noted required attention.  He stated that the mine operated almost every day of the year. 

   195  When he was maintenance supervisor at Golden Pig in 1998/99 there were approximately 12 people in the workshop crew.  Apart from his supervising work in the maintenance workshop he also went underground on a regular basis to attend to machinery.  He stated that each machine operating at the mine had a weekly service.  The haul trucks and boggers also had a 125, 250, 500, 750, 1,000 and 2,000 hour lubrication service.  He stated that employees did tag out machines from time to time, and that the practice was encouraged by the [respondent].  When a machine was tagged out there was usually another machine available to take its place. 

   196  Mr Gillman said that the leading hands and himself had authority to purchase seats, and he recalled purchasing seats.  There were also machines in the town yard which were cannibalised.  He stated that a lot of the reported seat faults did not require seat replacement but merely attention to the damper (shock absorber).  If a seat was not able to be repaired seats were available in the town yard, there being three to five spare seats available.  He estimated that vehicle seats were probably replaced several times a year.  He could not recall an occasion where a spare seat was not available when required. 

   197  Mr Gillman identified a service sheet dated 2 September 1999 as one of the service sheets used at Golden Pig (Exhibit 23).  He stated that during the weekly services it was the practice to get into and operate the trucks and boggers.  He stated that any problems connected with brakes, lighting, steering, seats or tyres was normally actioned immediately.  He had no recollection of the [appellant] complaining about the condition of seats or roads. 

   198  In addition to Golden Pig Mr Gillman had worked at Transvaal, Fraser's, Great Victoria and Marvel Lock in Western Australia and the Spring Creek Coal mine in New Zealand and he stated that the roads at Golden Pig were typical of the roads at other mines.  He stated that the main access, main decline and main haulage ways were graded, but the working headings were maintained by the boggers. 

   199  In cross‑examination he agreed that if there was a report of a seat being unsafe and the problem was not immediately rectified, somebody was falling down on their job.  He did not agree that the fact that there were regular complaints concerning the seating on a particular machine indicated that maintenance was defective, pointing out that the KAB 301 seat, being a single damper seat, did give rise to regular maintenance problems.  Mr Gillman did seem to agree that the machinery service check list did not contain a check seat item until about mid‑1999. 

   200  He agreed that from time to time there were problems with the dewatering system as a result of which excess water washed away road base.  So far as tyre pressure on the boggers and trucks was concerned he stated that they were set at the manufacturer's recommendation. 

   201  In re‑examination he was referred to service sheets relating to a bogger which demonstrated that in 1997 and 1998 there was a specific requirement to check seats and seatbelts.  The weekly service sheets dated 1 October 1997 and 10 January 1998 were tendered in evidence (Exhibit 24)."

The evidence of Craig McSkimming

1. Craig McSkimming was a maintenance supervisor employed by the respondent at Golden Pig.  The learned Judge set out, at [202] ‑ [207], relevant aspects of his evidence:

   "202  … It appears that he was a leading hand at the relevant time, and knew the [appellant].  He stated that he had driven boggers, haul trucks and light vehicles at Golden Pig and described the roads in the mine as 'generally acceptable'.  He stated that it was the bogger drivers' responsibility to look after the roads in the ore drives or headings.  He stated that bogger drivers were responsible for taking road base into the mine when required, and that is [sic] was customary then for them to back blade or spread the road base. 

   203  He confirmed that in 1998/99 the boggers and haul trucks were serviced weekly, with additional regular wet servicing which included oil and filter changes.  Running repairs were carried out when required.  He confirmed that the [respondent] operated an out of service tagging system, and plods, to bring to attention servicing requirements.  There was also daily maintenance of vehicles between shifts.  He stated that all operators were told to note any vehicle defects on their plods which were regularly checked by maintenance.  Maintenance requirements notified on the plods were generally attended to within a day. 

   204  Mr McSkimming stated that blown out shock absorbers was the most common problem with vehicle seats requiring changing of shock absorbers.  If the problem was irreparable, the seat would be taken out and replaced with a new or reconditioned seat.  Seats were also sent to Perth to be repaired.  He stated there may have been occasions when replacement seats were not available when required, but could not recall any occasion when a seat in a machine remained unserviceable for weeks. 

   205  Mr McSkimming was shown a time card for 3 September 1999 which had been completed by him demonstrating that a seat on B 15 had been replaced (Exhibit 25).  He was also referred to Exhibit 23 (the weekly service sheet) relating to B 15 which sheet he stated confirmed that on 3 September 1999 the seat on B 15 had been changed.  He believed a new seat had been fitted, although he was unable to establish that from documentation.  When it was put to him that the replacement seat might have been cannibalised from another machine he stated that was not a practice that was followed. 

   206  When it was put to him that plods indicated complaints about the seat on B 15 on 28 August 1999, 29 August 1999 and 3 September 1999 he was unable to provide an explanation as to why the problems had not been rectified save to say that it would have been checked on those occasions. 

   207  Mr McSkimming said that there were numerous occasions in the period of his employment where machines had been tagged out of service because of defective seats.  He stated that he was not aware from complaints or otherwise that road base was scarce on site from time to time, claiming that it was always available.  When he was challenged as to the availability of road base he stated: 

   'There is always road base underground.  You can always resurface the old stuff by grading it and rebogging the old sumps.'"

1. On the pleadings, and having regard to the expert evidence that was exchanged before trial, whether there was a concept of whole‑body vibration and, if so, its application, if any, to the appellant's case, was in issue between the parties.  In particular, Mr Schaeffer, in his report dated 15 March 2004, said he found it difficult to see how the alleged jolting and jarring experienced by the appellant would have resulted in any actual structural injury to his lumbar spine.

2. It is true that the respondent did not put to the appellant's expert witnesses (in particular, to Dr Gibson or Dr Harper) in cross‑examination the proposition that whole‑body vibration was unlikely to cause structural injury to the lumbar spine.  I do not consider, however, that such failure precluded the learned Judge from finding that whole‑body vibration was unlikely to result in such damage, particularly when regard is had to the state of the pleadings and the exchange of expert evidence which I have mentioned.  Further, the necessity for cross‑examination of Dr Gibson in relation to the concept of whole‑body vibration, and its application to the appellant's circumstances, was substantially diminished (if not wholly removed) by his concessions that:

   (a)he did not know the vibration levels when the appellant was driving the truck and the bogger (T201);

   (b)he did not know whether or to what extent whole‑body vibration affected the appellant because he had not taken any measurements in relation to the vehicles in question when driven on the roads at Golden Pig (T201); and

   (c)he was unable to say, in consequence of his not having done any tests, whether the appellant's exposure to whole‑body vibration exceeded or was less than any applicable health or safety standard (T202, 204),

   and also by his Honour's adverse findings in relation to the appellant's credit.

3. Ground 4 fails.

Ground 5

1. The learned Judge said, at [243], that Mr Schaeffer's evidence was consistent with the evidence of Dr Home. 

2. Dr Home said, relevantly:

   (a)Acute disc protrusion usually arises as a result of activity either on the day it happens or, if it occurs overnight, as a result of something that happened the previous day or the day before (T431).

   (b)An acute disc protrusion in a person who has underlying disc degeneration of some degree may be caused as follows:

   "the most common types of things that cause it are coughing when you are brushing your teeth or getting off a chair or picking up a pin from the ground.  It's usually something fairly innocent; you know, basically turning, twisting the body."  (T432).

   (c)He was heavily reliant upon the accuracy of the appellant's history (T432).

   (d)After the appellant's version of events, in relation to a history of continuous pain after 22 October 1999, was put to Dr Home in cross‑examination (T439), he said:

   "If you accept the history that he's giving in that version, you accept that something happened to his back on 22 October.  As I said before, it's very difficult to work out what that was."

   (e)It was also put to Dr Home, in cross‑examination (T439), that if the appellant had had constant pain which had not remitted, then that indicated a back injury at least on 22 October 1999, and Dr Home responded:

   "Of some sort, yes."

   (f)In cross‑examination (T439):

   "There was clearly a vulnerability of the disc in the period leading up to 2 January.  As I say, whether the jolting and jarring and so forth in the period is related to that, or whether that was causing pathology at one of the other levels of his back, is really speculative. …"

   (g)In cross‑examination (T439), in response to the proposition that pain is indicative of injury:

   "It's indicative of some process that causes pain.  That can be an injury.  Accepting that his pain came on 22 October then you would have to say there is a likelihood that he had some sort of injury at that time."

   (h)The appellant had degenerative changes at three levels and in consequence there were "lots of things that could have caused [the] pain he experienced on 22 October 1999" (T440).

   (i)As to the suggestion, in cross‑examination, that on 22 October 1999 there was a "fissuring of the disc but not a protrusion through the annulus", Dr Home said:

   "That's one possibility."  (T440).

   (j)Dr Home was then asked whether a minor event on 2 January 2000 or on the evening of 1 January 2000 was the "final insult".  He said:

   "It's possible.  It's speculative really.  I think if you are able to tolerate jolting and jarring for two months it's unlikely he did have an acute fissure in a disc because again you would expect, because of the anterior nature of those injuries, even a fissure, which causes back pain, people are intolerant sitting never mind sitting and jolting and jarring.  I think that's speculative, that sort of assessment."

3. In my opinion, a review of Dr Home's evidence indicates that it is substantially consistent with the evidence of Mr Schaeffer that:

   (a) "there must have been some advancement in the [appellant's] degenerative condition … within a few hours before he experienced that pain" on 2 January 2000 (T417); and

   (b)"symptomatic aggravation of pain may have occurred in October and the question as to the intensity and duration of that aggravation is to a considerable extent dependent upon the subsequent history" (T423).

   Significantly, Dr Home said (T440) that the appellant had degenerative changes at three levels and in consequence there were "lots of things" that could have caused his pain on 22 October 1999.  Although Dr Home's evidence indicated that he had greater uncertainty than Mr Schaeffer as to the cause of the appellant's pain between 22 October 1999 and 2 January 2000, his evidence did not materially advance the appellant's case.  In particular, in relation to Dr Harper's evidence that there was a fissuring of the disc on 22 October 1999 but not a protrusion through the annulus until 2 January 2000 (T440), Dr Home merely said that was "one possibility". 

4. Dr Home's evidence was, on the whole, broadly supportive of the evidence of Mr Schaeffer.  It was reasonably open to the learned Judge to prefer the evidence of Mr Schaeffer and Dr Home where, and to the extent that, it was inconsistent with the evidence of Dr Harper, Dr Kent and Mr Woodland.

5. Ground 5 fails.

Ground 6

1. Ground 6 is in substance repetitive of the allegations in grounds 1 ‑ 5.  It does not add anything of consequence.  For the reasons I have given in relation to grounds 1 ‑ 5, ground 6 is without merit.

Ground 7

1. The appellant's particulars of ground 7 set out the basis for his argument that the learned Judge failed to apply the proper principles to determine whether he could draw inferences from the evidence that the appellant had established a probable causal connection between the alleged injury he suffered on 22 October 2000 and the alleged jolting, jarring and vibration he experienced in the course of his employment, even if the medical evidence was to the effect that the alleged probable causal connection was only a "possible causal link".  The particulars are as follows:

   "7.1The appellant‑plaintiff had not suffered any symptoms to his back prior to 22 October 1999 apart from occasional twinges;

   7.2The appellant‑plaintiff was subject to jolting and vibration in the course of his employment as a truck driver and bogger driver with the respondent‑defendant;

   7.3Whole Body Vibration was known as a likely cause of spinal injury to Bogger and Truck drivers in the mining industry during the time that the appellant‑plaintiff was employed by the respondent‑defendant;

   7.4The appellant‑plaintiff's spine was likely to be twisted and at the same time jarred and jolted in a manner that would dispose the appellant‑plaintiff's spine to injury while he was working as a Bogger driver because he sat at right angles to the line of travel;

   7.5The appellant‑plaintiff developed pain while working as a bogger driver on 22 October 1999;

   7.6The day after the appellant‑plaintiff first suffered pain to his back he fell to the ground due to the pain to his back and had to be assisted to his feet by his wife;

   7.7From 22 October 1999 until 2 January 2000 the appellant‑plaintiff suffered continuous significant pain without pain free periods;

   7.8Between 22 October 1999 and 2 January 2000 the appellant‑plaintiff sought treatment from a naturopath and a chiropractor and took pain relief medication;

   7.9Although the appellant‑plaintiff continued to work he also continued to suffer significant pain;

   7.10On or about 2 January 2000 the appellant‑plaintiff suffered the disc prolapse that caused him to seek medical treatment;

   7.11All the treating physicians, Mr Stokes, Mr Woodland, Mr Kent and the occupational physician Dr Harper who saw the appellant‑plaintiff for the purpose of providing a report all agree that on the basis of the facts set out in paragraph 2.1 [sic] to 2.10 [sic] that the appellant‑plaintiff suffered an injury at work due to jolting, jarring and vibration on 22 October 1999;

   7.12Dr Home's evidence conceded that there was a possibility that the appellant‑plaintiff suffered a fissure to his lumbar disc as described by Dr Harper as a result of working as a bogger driver and truck driver."

   Once again, this ground substantially repeats earlier grounds.

2. The learned Judge considered carefully the evidence as to causation and the findings made by him were reasonably open.  His Honour was entitled to find against the appellant on the issue of causation, in circumstances where:

   (a)his Honour made the adverse findings in relation to the appellant's credit, which I have mentioned;

   (b)the evidence of Mr Stokes, Mr Woodland and Dr Harper was that, in forming their opinions, they relied on the accuracy and cogency of the appellant's history;

   (c)there was a substantial body of evidence to the effect that:

   (i)the roads within Golden Pig were serviceable;

   (ii)the seats in the haul trucks and boggers were in reasonable condition and adequately maintained; and

   (iii)there were infrequent complaints made by the appellant, and a paucity of complaints by other employees of the respondent, in relation to the condition of the roads and seats; and

   (d)his Honour accepted the evidence of Mr Schaeffer and Dr Homes, and apparently preferred their evidence where it differed from the evidence of the other experts.

3. The learned Judge did not make an error of law, as alleged in ground 7.  The ground is without merit.

Grounds 8 and 9

1. Grounds 8 and 9 overlap in substance with aspects of grounds 1 ‑ 7. 

2. The learned Judge's findings made it unnecessary for him to consider whether any jarring, jolting and vibration experienced by the appellant, in the course of his employment, made a contribution to his injuries which was more than negligible, and therefore material.  As I have mentioned, in the context of examining grounds 1 ‑ 7, the findings in question were reasonably open to his Honour. 

3. The appellant relied on Chance v Alcoa of Australia Ltd (1990) A Tort Rep 81‑017.  In Chance, Malcolm CJ said, at 67,726 ‑ 67,727:

   "Where there are possible competing causes it is sufficient if the evidence would support an inference that the defendant's negligence 'materially contributed' to the plaintiff's injury: McGhee v National Coal Board [1973] 1 WLR 1 at 6 per Lord Wilberforce; as explained by Lord Bridge in Wilsher v Essex Area Health Authority [1988] 2 WLR 557 at 560. In the present case there was a finding of negligence against the respondent for failing to provide a safe system [of] work so as not to expose the applicant to the risk of injury to his eyes by caustic soda burns. Although the incidence was rare it was known that caustic soda burns to the eye caused the condition of dry eye. The appellant was exposed to caustic soda burns in both eyes on separate occasions. He later contracted the dry eye condition which affected both eyes with differing severity. There was another competing explanation for the condition, namely that it was idiopathic, but the condition so caused was extremely rare in men under 50 years of age.

   In my opinion the state of the evidence was such that on Professor Constable's evidence the proper inference of fact was that on the balance of probabilities the caustic soda burns had materially contributed to the onset of the dry eye condition.  The learned Judge does not appear to have appreciated the significance of the relevant evidence given by Professor Constable.  In these circumstances, having regard to the general view which the learned Judge took of Professor Constable's evidence, this Court is entitled to draw the relevant inference for itself: cf Warren v Coombes (1979) 142 CLR 531. In The London Bank of Australia Ltd v Kendall (1920) 28 CLR 401 at 407 Isaacs and Rich JJ said:

   '... it is the duty of the appellate tribunal (and it is the statutory right of the litigant who invokes it to require of it the performance of that duty) to determine for itself the true effect of the evidence so far as the circumstances enable it to deal with the evidence as it appeared in the Court of first instance ...'

   See also McLaughlin v Daily Telegraph Newspaper Co Ltd (1904) 1 CLR 243 at 277 per Griffiths CJ."

4. In the present case, the learned Judge did not fail to appreciate the significance of any relevant evidence given by any of the expert witnesses.  Further, the findings which his Honour made (and which were reasonably open to him) precluded the making of a finding or the drawing of an inference that any jarring, jolting and vibration experienced by the appellant, while he was driving the trucks and boggers, materially contributed to the injuries of which he complained. 

5. The appellant's reliance upon such authorities as Watts v Rake (1960) 108 CLR 158, and Purkess v Crittenden (1965) 114 CLR 164, is misplaced. The principle in Watts, as explained in Purkess by Barwick CJ, Kitto and Taylor JJ, at 168, is as follows:

   "We understand [Watts] to proceed upon the basis that where a plaintiff has, by direct or circumstantial evidence, made out a prima facie case that incapacity has resulted from the defendant's negligence, the onus of adducing evidence that his incapacity is wholly or partly the result of some pre-existing condition or that incapacity, either total or partial, would, in any event, have resulted from a pre-existing condition, rests upon the defendant.  In other words, in the absence of such evidence the plaintiff, if his evidence be accepted, will be entitled to succeed on the issue of damages and no issue will arise as to the existence of any pre-existing abnormality or its prospective results, or as to the relationship of any such abnormality to the disabilities of which he complains at the trial.  It was, we think, with the character and quality of the evidence required to displace a plaintiff's prima facie case that Watts v. Rake was essentially concerned.  It was, in effect, pointed out that it is not enough for the defendant merely to suggest the existence of a progressive pre-existing condition in the plaintiff or a relationship between any such condition and the plaintiff's present incapacity.  On the contrary it was stressed that both the pre-existing condition and its future probable effects or its actual relationship to that incapacity must be the subject of evidence (i.e. either substantive evidence in the defendant's case or evidence extracted by cross-examination in the plaintiff's case) which, if accepted, would establish with some reasonable measure of precision, what the pre-existing condition was and what its future effects, both as to their nature and their future development and progress, were likely to be.  That being done, it is for the plaintiff upon the whole of the evidence to satisfy the tribunal of fact of the extent of the injury caused by the defendant's negligence."

   Also see the observations of Windeyer J at 171 - 172.

6. In the present case, on the findings which the learned Judge made (and which were reasonably open to him) the appellant did not establish a prima facie case that his alleged injuries resulted from the respondent's negligence.

7. Grounds 8 and 9 fail.

Ground 10

1. The learned Judge said, at [242]:

   "The application of commonsense suggests that if the [appellant's] body had been subjected regularly to the kind of forces which he claimed, and that it was having a cumulative effect upon the integrity of his spinal column, there would have been some symptomological [sic] indication thereof before 22 October 1999."

2. That observation follows the learned Judge's rejection, at [241], of the appellant's evidence as to the extent of the deficiencies in the vehicle seating and the condition of the roads, and the extent of the forces applied to his body as a result of both of those matters.

3. The observation in question precedes the learned Judge's apparent acceptance, at [247] ‑ [248], of evidence given by the respondent's witnesses to the effect that:

   (a)the roads within Golden Pig were serviceable and of an equivalent standard to those encountered at numerous other mine sites; and

   (b)the seats on the haul trucks and boggers were of a reasonable condition and adequately maintained.

4. In my opinion, the learned Judge's observation, at [242], was erroneous in that any conclusion to that effect should have been arrived at by applying the relevant medical evidence (accepted by his Honour) to the relevant facts (found by his Honour).  The observation does not, however, vitiate his Honour's findings, as to the appellant's credit or as to the condition of the seats and the roads, in that it was not an essential element of the reasoning process which culminated in the rejection of the appellant's claim.  In those circumstances, the complaint in ground 10 does not require the setting aside of any material findings made by his Honour.

Ground 11

1. Ground 11 overlaps in substance with aspects of grounds 1 ‑ 10.

2. It was reasonably open to the learned Judge to find that the cause of the disc prolapses which occurred on 2 January 2000 was a matter of conjecture.  His Honour said, at [239]:

   " … It is not possible to determine on the evidence whether what occurred on 22 October 1999 was a spontaneous occurrence or the manifestation of some traumatic event.  Since the [appellant] cannot recall a specific event, the state of the evidence is such that a choice between the two is a matter of mere conjecture.  I am, however, unable on the evidence to conclude, on the balance of probability, that any work activity the responsibility of the [respondent] can be identified as causative. … "

3. In my opinion, the learned Judge's conclusion that it was not possible to determine whether what occurred on 22 October 1999 was a spontaneous occurrence, or the manifestation of some traumatic event, was based not merely on the appellant's inability to recall a specific event, but on all of the relevant evidence at trial.  For that reason, and also for the reasons I have given in the context of grounds 1 ‑ 10, I am satisfied that his Honour did not make an error of law or fact as alleged in ground 11.

Ground 12

1. Ground 12 overlaps in substance with aspects of grounds 1 ‑ 11.

2. As I have mentioned, there was substantial evidence, from witnesses called by the respondent, to the effect that:

   (a)the roads within Golden Pig were serviceable and of an equivalent standard to those encountered at numerous other mine sites; and

   (b)the seats on the haul trucks and boggers were of a reasonable condition and adequately maintained.

   It is apparent, from the learned Judge's findings at [247] ‑ [249], that his Honour accepted that evidence.  His Honour's conclusions, at [249], were these:

   "The evidence establishes that underground mining is a harsh environment where road surfaces, vehicle seating and working conditions generally must of necessity be ever changing.  I am satisfied that the [respondent] had in place an appropriate maintenance and supervision system to respond to that environment.  Although deficiencies in the state of equipment and the condition of the roads are identified in the documentation referred to by the [appellant], it is abundantly clear from the records generally that they were no more than would necessarily be expected and unavoidable in this particular activity."

   For the reasons I have given in the context of grounds 1 ‑ 11, the findings and conclusions to which I have referred, in the context of ground 12, were reasonably open to his Honour.  The appellant has not made out an error of law, as alleged. 

Ground 13

1. The appellant alleges that the learned Judge erred in law and in fact in finding that he was satisfied that the respondent had in place an appropriate maintenance and supervision procedure and that the deficiencies in the roads and equipment were no more than to be expected in the harsh environment.  Ground 13.1 alleges that the learned Judge erred in law, in determining whether the respondent was negligent, by failing to apply the appropriate test, namely, whether the respondent had met the standard of care required at law.  The particulars of ground 13.2 set out the basis for the appellant's argument that his Honour should have found, on the evidence, that the respondent, without reasonable cause, had failed properly to maintain the seats and the roads.  The particulars are as follows:

   "13.2.1.The evidence of Stanley Gillman as found by his Honour proved that no road base was purchased by the respondent‑defendant in January, May, September, October, November and December 1998 nor in May, July or August 1999;

   13.2.2.The evidence from the minutes of the safety committee meetings and Occupational Health and Safety committee meeting showed that there were extended periods of time when road base was scarce and not available to grade the roads;

   13.2.3.The evidence from the respondent‑defendant's records of repairs to the seats showed that the seats were not repaired in an expeditious manner;

   13.2.4.The evidence from the PLODs and other documents produced by the appellant‑plaintiff showed that the roads and seats were poorly maintained;

   13.2.5.The evidence of John Kent Gillman proved that the respondent‑defendant was aware that suspension on the seat used in the vehicles driven by the appellant‑plaintiff being the KAB 301 was unsatisfactory and gave rise to problems yet the respondent‑defendant continued to provide the seat for the use of its employees until after the appellant‑plaintiff was injured;

   13.2.6.The evidence of Dr Chew the respondent‑defendant's expert witness was that to allow a driver to drive over rough roads in mining conditions for even a few days increased the risk of injury to the driver;

   13.2.7.The respondent‑defendant knew that rough roads and poorly maintained seats were likely to cause injury to the appellant‑plaintiff."

2. As to ground 13.1:

   (a)An employer owes a non‑delegable duty of care to its employee to take reasonable care to avoid exposing him or her to unnecessary risks of injury.  If there is a real risk of injury to an employee in the performance of his or her work, the employer must take reasonable care to avoid the risk by adopting a method of operation for the performance of the task which eliminates the risk, or by the provision of adequate safeguards.  See Czatyrko v Edith Cowan University (2005) 79 ALJR 839 at 842 ‑ 843. Also see Bankstown Foundry Pty Ltd v Braistina (1986) 160 CLR 301 at 307 ‑ 308.

   (b)The learned Judge did not make an error of law, as alleged.  It was necessary for his Honour to determine what a reasonable employer in the position of the respondent would have done to avoid any foreseeable risk of harm to its employees from the condition of the seats in the trucks and boggers and the condition of the roads.  The nature of the working environment was a relevant consideration in determining what reasonableness required of the respondent. 

3. As to ground 13.2, the learned Judge did not err, as alleged.  It is important to appreciate the precise terms of the relevant findings which his Honour made.  In particular:

   (a)his Honour was satisfied, on the evidence, that there were occasions when one or more vehicles had defective seats which were not promptly repaired or replaced and, further, there were occasions when roads were below optimal standard and when there was a lack of adequate road base:  [248];

   (b)his Honour was also satisfied, however, that the respondent had in place an appropriate maintenance and supervision system to respond to the harsh environment, and that it was abundantly clear from the documentary records that those deficiencies which had occurred were no more than would necessarily be expected and unavoidable in this particular activity:  [249]; and

   (c)his Honour reiterated, in effect, his earlier adverse finding in relation to the appellant's credit by noting, at [248], that if the position in relation to maintenance was as suggested by the appellant then the documentary records would have revealed the making of many more complaints:

   " … only a very small proportion of the PLODS tendered in evidence (37 out of approximately 6000) complain about vehicles or road conditions.  The position is similar with the maintenance meeting minutes. …"

4. During a period of approximately two years, the appellant made a complaint about his work conditions at one safety meeting.  In addition, between 1 November 1998 and 24 December 1999 the appellant made one complaint regarding an unsafe seat (on 4 June 1999) and one complaint regarding the condition of the roads (on 1 April 1999).

5. According to Mr Stanley Gillman's evidence, the Golden Pig mine operated for 51 weeks per year and there were three shifts per day.  The drivers of the trucks and the boggers completed 54 plods each week and other employees completed 42 plods each week, making a total of 96 plods per week.  Between 1 November 1998 and 31 January 2000 there were 63 working weeks which generated 6,048 plods.  The appellant referred to 26 plods which mentioned the need to repair or replace seats, and 11 plods which mentioned the need for road base.

6. It is apparent, therefore, with regard to seats, that the rate of complaints was 1.73 complaints per month, or 0.43 per cent of all plods completed by employees.  Further, it is apparent, with regard to roads, that the rate of complaints was 0.73 complaints per month, or 0.18 per cent of all plods completed by employees.  In other words, 99.57 per cent of the plods made no complaint about seats, and 99.82 per cent of the plods made no complaint about the roads. 

7. There was no evidence that anyone had suffered any injury while driving a bogger or a truck at the Golden Pig mine (apart from the appellant's allegations in relation to himself). 

8. The appellant gave evidence at trial that the seats and the roads were generally defective, but, as I have mentioned, the learned Judge did not accept his evidence in that respect.  Numerous witnesses called by the respondent gave evidence which contradicted the appellant.

9. The appellant said in evidence that he complained regularly about the state of the roads throughout 1998, but in 1999 he reduced the frequency of his complaints because Mr Stanley Gillman threatened to dismiss him.  Mr Stanley Gillman denied the appellant's evidence in that respect.  The learned Judge did not make an express finding in relation to the conflict of evidence between the appellant and Mr Stanley Gillman.  It is apparent, however, from the findings I have set out at par [134] above, combined with his Honour's finding, at [241], that the appellant had significantly exaggerated the extent of the deficiencies in the vehicle seating and the condition of the roads, that his Honour must have preferred Mr Stanley Gillman's evidence to that of the appellant.

10. The learned Judge did not, in his reasons, make an extensive analysis of the documentary evidence (in particular, the plods and the maintenance meeting minutes), but I am not persuaded that, in the circumstances, such an analysis was necessary.

11. The learned Judge did not refer to some evidence given by Mr McDonald (at T275 ‑ 276 and T283 ‑ 284) which, to some extent, supported the appellant's evidence in relation to the condition of the roads and the seats. It is plain, however, from the findings of his Honour to which I refer at [134] above that his Honour did not accept the appellant's case and that his Honour preferred the evidence of the witnesses called by the respondent.

12. The appellant's argument that a failure to maintain roads or seats "even for a short time created a risk of injury to the appellant‑plaintiff" is not relevant in circumstances where it is plain, on the appellant's own evidence and the medical evidence which his Honour accepted, that an injury did not occur in one of those short periods. 

13. Although the respondent's maintenance and supervision procedure in relation to the seats and the roads was imperfect, a perfect system is not required, and there was evidence which provided a reasonable basis for the learned Judge to make the findings which are attacked in ground 13.2.  His Honour did not make an error as alleged, and the findings in question were reasonably open to him. 

14. Ground 13 fails.

Ground 14

1. Ground 14 repeats, in substance, the earlier grounds.  It adds nothing new.  For the reasons I have given in relation to the earlier grounds, I find that ground 14 is without merit.

Conclusion

1. The appeal should be dismissed.