COURT IN THE FEDERAL COURT OF AUSTRALIA NEW SOUTH WALES DISTRICT REGISTRY GENERAL DIVISION FOSTER J HRNG SYDNEY, 27-28 February; 1-3, 6-9, 13-17, 21-24, 27-31 March; 3-5, 10-11, 13, 19-20, 24, 26-28 April and 1 May 1995 #DATE 14:12:1995 #ADD 18:1:1996 Counsel for the Applicant: Mr A. Puckeridge QC with Mr R. Wilkins Instructed By: Maurice May and Co Counsel for the Respondent: Mr J. Mccarthy QC with Mr P. Jones Instructed By: Australian Government Solicitor ORDER THE COURT ORDERS THAT: 1. The application be dismissed. 2. Costs be reserved. Note: Settlement and entry of orders is dealt with in Order 36 of the Federal Court Rules. JUDGE1 FOSTER J In these proceedings, which were commenced in the High Court of Australia and transferred to this Court, the applicant, Pedro Juan Cubillo ("Cubillo"), sues the Commonwealth of Australia to recover damages for personal injury and consequential loss allegedly sustained by him as a result of his employment by the Commonwealth at Maralinga, South Australia, in the years 1957 and 1958. 2. Cubillo was a Private in the Australian Army. He was a sapper in the Royal Australian Engineers and performed various duties in relation to the construction and dismantling of test sites and equipment used in the series of atomic explosion tests conducted in 1957 ("the Antler series"). He claims that as a result of the negligence of the Commonwealth, as his employer, he was wrongfully exposed to ionising radiation, which exposure caused him to suffer from renal cell carcinoma some 20 years later. The Commonwealth has denied liability in every respect. It has denied the acts and omissions relied upon as constituting negligence. It has also denied that the specific cancer suffered by Cubillo was caused or contributed to by any activity engaged in by the applicant during his employment at Maralinga. 3. The evidence given in the case has covered many fields of scientific expertise. Expert witnesses, some of international renown, have provided scientific opinion from the fields of health physics, radiobiology, epidemiology, and oncology. The evidence has been complex and detailed with some significant differences of opinion. The evidence of lay witnesses has suffered from the difficulty of recalling events occurring nearly 40 years ago. Before entering upon a consideration of the evidence, it is convenient, by way of background, to set out certain matters as to which there appears to be no contest and to make findings in certain contested areas. THE MARALINGA TESTING AREA 4. The Antler series of tests was part of the overall program of testing of atomic weapons by the British Government on the Australian mainland and adjacent islands. The Australian Government had agreed to cooperate with the British Government in the conduct of these tests which involved the detonation of nuclear weapons and devices associated with them. Pursuant to that agreement personnel of the Australian armed forces took part, at various sites and various levels, in the preparation for and conduct of the tests and the cleaning up operations which followed. It appears that in 1954 the Maralinga area had been identified as an appropriate site for the conducting of a number of these tests. 5. The Maralinga proving ground consisted of a large area of desert country in South Australia. It had been selected to minimise any difficulties or danger which might be occasioned by the tests to centres of population. A very considerable infrastructure was established. A village, known as the Maralinga Village, was built in proximity to a railway stop on the trans-Australia railway, known as Watson. The village housed a large number of personnel involved in the tests and the logistics associated with them. There is no need to describe it. It was carefully planned to deal with the scientific necessities for the experiments and to provide for the comfort and convenience of personnel, scientific and non-scientific, military and non-military, involved in the project. 6. Some 8 miles to the north of Maralinga Village a forward base, known as "Roadside" was established. This was in the nature of a "tent city" which housed and provided amenities for personnel working on the construction of the test sites and in the assembly of the scientific apparatus required for the tests, including the assembling and positioning of the weapons themselves. The applicant and other personnel of the Royal Australian Engineers lived in this area during the test operations. 7. The desert area to the north of Roadside was referred to as "the forward area". It was in designated parts of this area that the nuclear tests were carried out at specially prepared sites. Access to this area was controlled by security officers stationed at Roadside. There was an established sealed road from Maralinga Village to Roadside and through Roadside to the various parts of the forward area where work was being done. Permission was required to proceed beyond Roadside. Vehicular access was controlled by a boom gate operated by a "peace officer", a member of the Australian Federal Police. SECURITY MEASURES FOR PERSONNEL IN THE FORWARD AREA 8. In the forward area there were elaborate security arrangements. These were put in place not only to ensure the secrecy of the tests, but also as a means of ensuring compliance with regulations imposed for the safety of personnel. To this end, observation towers were erected in the forward area to enable security officers to observe all working parties in the forward area and to determine whether they were keeping outside areas where there could be dangerous levels of radioactivity. In association with these observation towers there were roving patrols in Land Rover vehicles which could proceed quickly to any location should a problem arise. There was radio contact between these patrol vehicles and the observation towers. 9. It was understood that after each nuclear explosion there would be areas of danger associated with radioactive fallout. It was also understood that it would be necessary for personnel to perform work of various kinds in areas affected by radioactivity in varying degrees. Accordingly, it was necessary to take steps to prevent harm to such personnel. Procedures were put in place which were implemented by scientific personnel known as the "health physics group". This group was responsible for establishing the boundaries of zones affected by radioactive fallout immediately after each nuclear explosion, marking those boundaries, and thereafter monitoring them by taking readings with appropriate scientific instruments. 10. It appears that the areas of radioactivity receded with the passing of time so that the boundaries would contract in the direction of the point of the explosion, which was known as "ground zero". It was the responsibility of the health physics group to ensure that all personnel, including their own, who entered into radioactive areas were appropriately clad in protective clothing. The extent of this clothing depended upon the classification of the area as either "yellow", "red" or "blue". 11. Yellow, red and blue areas were defined in the "Radiological Safety Regulations Maralinga" ("the Regulations") which were agreed upon by the United Kingdom and Australian authorities concerned and promulgated in 1956. They were issued by the "Director, Atomic Weapons Research Establishment of the United Kingdom". They made detailed provision for maximum permissible levels of radiation exposure for different types of radiation and for the use of protective procedures and equipment. The colour-designated areas referred to above were defined in the Regulations as follows:- "3.2.1 Non-Active Areas A NON-ACTIVE area is one in which the maximum radiation levels do not exceed 1/10 of those laid down in Section 2 above for ACTIVE areas and there is no detectable loose activity. No special radiological precautions will be necessary. 3.2.2 ACTIVE Areas Those in which there may be some radiation risk and where precautions appropriate to the degree of risk must be taken. There will be three categories: (a) BLUE area - Risk of penetrating radiation but not of inhalation, ingestion or injection. No special clothing. (b) RED area - Risk of penetrating radiation and of slight inhalation, ingestion and injection. Protective clothing will be worn in accordance with Health Physics recommendations for the particular area. (c) YELLOW area - Risk of serious inhalation, ingestion, injection or penetrating radiation hazard. Fully protective clothing must be worn. 3.2.3 The classification of an area will be laid down by Health Physics representatives who must be informed prior to any proposed change in the work which might affect the classification. Health Physics representatives will review the classification periodically. 3.2.4 Signs showing the classification and having a patch of the appropriate colour will be displayed at all entrances to any ACTIVE area. All areas not classified in this way will be NON-ACTIVE areas and these will not have any special marking. 3.3 No person will be allowed to enter RED or BLUE areas without permission of the Scientist, or other Officer, in charge of the area concerned. No person will be allowed to enter a YELLOW area without permission from the Health Control Officer in charge. When it is necessary to carry out any building, engineering or other maintenance work in any ACTIVE area, a 'Permit to Work Certificate' must first be raised through the Group Leader, Range Facilities, who will consult Health Physics representatives where necessary. 4. FILM BADGES All personnel will wear a Personal Monitoring Film at all times. 5. PROTECTIVE CLOTHING 5.1.1 All radiological protective clothing will be WHITE, and will be distinguished by RED epaulettes or a RED triangle as appropriate. 5.1.2 The wearing of the approved protective clothing with film badges and dosimeters as specified in the appropriate parts of the Regulations is compulsory. 5.1.3 To assist the rigid enforcement of these rules under no circumstances will radiological protective clothing be issued for other purposes. 5.2 Degree of Protection 5.2.1 Workers in BLUE areas - No special protective clothing necessary. 5.2.2 Workers in RED areas - Approved laboratory coats or overalls, shoes or overshoes. The above is general for all RED areas but in certain special cases additional clothing will be specified by Health Physics representatives. When worn in ACTIVE areas laboratory coats and overalls must be kept fastened at all times. 5.2.3 Workers in YELLOW areas - Complete change of all clothing into the fully protective items provided." 12. The full protective clothing to be worn in yellow areas consisted of a garment which covered the entire body including the head. Additionally, boots and gloves were worn to protect the hands and lower limbs and a respirator was provided to prevent the inhalation of any airborne radioactive contaminants. It is not suggested that this clothing, if worn, was inadequate to protect against radioactive contaminants relevant to this case. 13. After a nuclear explosion, only a portion of the forward area would be contaminated. It was possible to go north from Roadside for some miles in the direction of the relevant ground zero before any danger of radioactive contamination could occur. Before anyone proceeding into those areas actually reached them it was necessary to be processed through a health physics "caravan". This was a highly designed installation which could be moved from place to place in the forward area. It is unnecessary to describe it in detail. It is not contested that it was adequately designed for the purpose of monitoring and providing for the radiation safety of personnel going through it and beyond into contaminated areas. 14. Personnel going into those areas would leave the vehicles which they had used to come to the caravan in an adjacent uncontaminated area. They would then pass through the stages of the caravan where they would be issued with protective clothing appropriate to the task they were to perform and also with the film badge and, if necessary, the dosimeter referred to in the Regulations cited above. The film badge was a device which recorded the level of radiation to which its wearer was exposed. This level was ascertained subsequently by the development of the film contained within it. This was done in a laboratory in the Maralinga Village. Records were kept of the radiation doses received by the individual wearer. The dosimeter device enabled an instantaneous reading of the level of radiation to which its wearer was exposed. Although some evidence has been given in the case as to occasional defects in the operation of these devices, I am satisfied that, in general, they worked satisfactorily. There is no suggestion in the case that, in themselves, they were other than appropriate measuring devices for the purposes for which they were designed. 15. Upon return from radioactive areas, the personnel re-entered the health physics caravan. Their clothing was monitored for any adhering contaminants using a measuring instrument called a "geiger counter". Their clothing was then removed and their bodies similarly monitored. If any contamination was present, the person affected was required to wash until cleared of any contamination. He then resumed his own clothing, returned to the vehicle which had been left in the carpark and proceeded back to Roadside. Again, it is not suggested in this case that the procedures in relation to monitoring and decontamination in the health physics caravans were inadequate. 16. There was evidence tendered on behalf of the applicant that there were defects in relation to the processing of film in the film badges with the result that readings were not obtained or were defective. Countervailing evidence has been given, which I accept. I am satisfied that the health physics procedures were appropriate for the task of monitoring the radiological safety of personnel and that they were generally applied in a diligent manner. There is a question, however, as to whether, prior to the Antler trials, the ordinary health physics procedures could not be implemented because of circumstances to which I shall refer later. 17. In addition to the sealed roads referred to above, there were also unsealed roads leading into portions of the forward area. These roads were not for general use but were restricted to vehicles used by the health physics group. These vehicles could, from time to time, be contaminated by radioactive materials. They were painted yellow for the purpose of distinguishing them from other vehicles used by personnel in the area. They were used only on these roads which were given the name "yellow" roads. It is not suggested that the segregation of these vehicles and these roads was, in any way, ineffective in preventing personnel such as Cubillo from coming into contact with contaminated vehicles or road surfaces. 18. The evidence establishes to my satisfaction that a system of warning signs was put in place. These signs were placed in appropriate positions on roads in the forward area which were used by personnel working in the area. After leaving Roadside and heading north, vehicles came to a sign at the side of the road shortly to the south of a site known as "Iwara". This sign was in red on a white background. It read "WARNING - CONTROLLED AREA - NO ENTRY - UNLESS AUTHORISED BY THE RANGE COMMANDER OR HIS REPRESENTATIVE". This sign was erected well to the south of any areas which could be contaminated by radioactive fallout from the tests. 19. As vehicles proceeded north from Iwara, other sealed roads became available to them leading towards the explosion sites. Each of these roads was controlled by further warning signs erected in reasonable proximity to, but well short of, contaminated areas. These signs were in black on a yellow background. They read "WARNING - YOU ARE APPROACHING A RADIOACTIVE AREA". 20. When the roads reached the actual boundary of an area designated as subject to radioactivity, further signs were erected. These signs were red on a yellow background. They read "DANGER - RADIOACTIVE AREA - NO ENTRY - UNLESS WEARING FULL PROTECTIVE CLOTHING AND TRAVELLING IN A YELLOW VEHICLE". This sign reflected the fact that entry into radioactive areas was to occur only in health physics vehicles driven and occupied by personnel who had passed through the health physics caravan and been issued with appropriate protective clothing. 21. Although it might be said to have been faintly disputed in the evidence, I am quite satisfied that these signs were in position at all relevant times. Their existence and position is clearly attested to by the evidence of an Australian scientist, Mr Moroney, whose evidence in relation to this and other matters I fully accept. 22. In addition to these warning signs, the existence of contaminated areas was depicted upon maps. The regulations provided for the creation and distribution of such maps which were to show the boundaries of active areas. These were to be updated from time to time. I am satisfied, on the evidence of Mr Flannery, who was the Range Security Officer at relevant times, that such maps were in fact brought into existence and that they contained information supplied by Mr Turner, who was the Australian scientist in charge of health physics between the Buffalo series (referred to later) and the Antler series. 23. I am satisfied that a basic map came into existence at the termination of the Buffalo series and that the radioactive area at that time was depicted by hatching on the map. Mr Flannery was of the view that copies of this map, produced on a Gestetner copying machine, were in fact distributed to all personnel working on the range. His evidence satisfies me that they were at least distributed to relevant officers in sufficient numbers to enable their further distribution to men under their command. 24. Cubillo and other witnesses, to whom I shall refer later, and who were sappers performing similar work to him, deny ever having received such a map. It is possible that they did not. In any event, having regard to their rank and their ages, it is not likely, in my view, that they would have paid much attention to it. As army privates they would not have expected to be permitted to exercise any independent discretion as to where they travelled in the forward area to do their work. I am satisfied, however, that, in general terms, provision was made for the supply of these maps to all personnel and that a copy would have been quite readily available to anyone who was interested. I am also satisfied that the map was displayed on a noticeboard in the Roadside area. The map became the basis of other maps which have been tendered in evidence and which I shall refer to later. 25. It may be noted that the map in question merely delineated one "yellow control area". It did not attempt to delineate red or blue areas. Indeed, so far as I can determine on the evidence, no blue area was ever the subject of delineation. After the conclusion of the Antler trials a red area was established for the first time. I shall refer to the yellow and red areas later in these reasons. THE BUFFALO TEST SERIES AND THE INTER-TRIAL PERIOD 26. Prior to the Antler series, the Maralinga range had been used for a series of experimental nuclear explosions, known as the "Buffalo" series. In that series four nuclear weapons were detonated at separate sites within the range. The first bomb was detonated on 27 September 1956 at a site referred to as "One Tree". The second was detonated on 4 October at a site referred to as "Marcoo". The third explosion occurred on 11 October at a site referred to as "Kite". The fourth occurred on 22 October at a site referred to as "Breakaway". All these sites were, of course, within the forward area. The detonations and health physics operations in relation to them were under the control and supervision of the British authorities. After the detonation at Breakaway the range was handed over to the Australian authorities for supervision until the British resumed control on 6 August 1957. In the meantime work was done in relation to the preparation of sites for the Antler series of tests. 27. The period between October 1956 and August 1957 is described as the "inter-trial" period. During this period the health physics requirements of the range were provided by an Australian health physics group under the command of Mr Turner, to whom I have already referred. The Court was informed that Mr Turner was too frail and old to be a witness in these proceedings. However, during the inter-trial period Mr Turner provided monthly health physics reports which have been admitted into evidence. I shall refer to relevant parts of these reports later in these reasons. THE ANTLER TEST SERIES 28. There were three explosions in this series. The first was detonated at a site referred to as "Tadje". This occurred on 14 September 1957, the weapon being exploded on a tower 30 metres high and having an explosive force of one kiloton. The second was detonated at a site referred to as "Biak". The explosion occurred on 25 September. It was of the same force and was also detonated on a tower 30 metres high. The final explosion in this series was at a site referred to as "Taranaki". It took place on 9 October. The weapon was attached to a balloon at an elevation of 300 metres. The explosive force was 25 kilotons. Other sites had been prepared for this series but they were not in fact used. These sites were called "Gona" and "Tufi". 29. I attach to these reasons, as Schedule 1, a map, obtained from the evidence, which shows the forward area from Roadside, the relevant roads and the positions of the ground zeros for the explosions in the Buffalo and Antler series, together with other features referred to in the evidence. THE MINOR TRIALS SERIES 30. A further series of tests, known as the "minor trials series", were also conducted on the Maralinga range. These were conducted in areas away from the ground zero sites of the Buffalo and Antler series. They were performed at sites referred to as "Kittens", Tims", and "Naya". The evidence of Mr Flannery and others clearly indicated that these tests were "top secret", conducted by and open to only British scientific personnel. The preparatory work was different in kind from the work associated with the Buffalo and Antler trials. It was of a highly sophisticated scientific nature and could only be performed by highly trained scientific personnel. 31. Cubillo's case was initially presented on the basis that he worked in these areas in relation to these trials. However, that case was abandoned during the hearing. The decision to do so was clearly correct as Mr Cubillo's extremely vague recollections in this regard could not prevail against the weight of testimony to the effect that he could not possibly have been involved in any work relating to these tests. The abandonment of this part of his claim was also of significance in another respect. The minor trials tests provided the only opportunity for possible exposure to the radionuclide polonium 210. Such exposure had also formed part of Cubillo's case. It was also abandoned and, in my opinion, on the evidence, properly so. SOURCES OF RADIATION FROM THE BUFFALO AND ANTLER TRIALS 32. Considerable evidence was given as to the sources, measurement, distribution and potential physical dangers of ionising radiation from these trials. It is unnecessary to consider this evidence in great detail as the claims made by Cubillo fall within a narrow area. It is clearly established that the tests, both as a result of the explosions themselves and the fallout from them, were productive of ionising radiation in the form of gamma rays, beta rays, and alpha rays. Gamma rays achieve a high degree of penetration through objects animate and inanimate in their path. It is the ionising radiation involved in these rays which is measured by the dosimeters, film badges and geiger counters already referred to. Beta rays have considerably less penetrating power. Cubillo's case does not involve any consideration of them or their effect. I shall not refer to them further. Alpha rays have little penetrative capacity, with the result that the external exposure of the human body to them is of no significant consequence. However, the evidence establishes that if a radionuclide having the capacity to emit alpha rays actually enters the human body by being inhaled or ingested, then it has the potential to cause harm, particularly as a carcinogenic agent. 33. It is Cubillo's case that he was wrongfully exposed to "alpha-emitters" during the course of his work at Maralinga, and that during the course of his work he either inhaled or ingested the alpha emitters with the result that he subsequently developed a renal cell carcinoma. As I have already indicated, at the outset of his case, he identified one such alpha-emitter as being polonium 210. The alleged inhalation or ingestion of this radionuclide was abandoned along with his contention that he worked in the minor trials areas. As a result, his case came to depend upon the contention of inhalation or ingestion of the only other alpha-emitting radionuclide present at Maralinga, namely plutonium 239. 34. Considerable evidence was given as to the nature and properties of plutonium 239. Evidence was also given as to its creation through the nuclear explosions of the Buffalo and Antler series and its subsequent distribution in the test areas. I shall consider the detail of this evidence later. It will also be necessary to consider conflicting scientific testimony in the case as to the potential effect on the kidney of the introduction into the human body by inhalation or ingestion of plutonium 239. 35. In considering this testimony regard will have to be paid to scientific terms used in relation to various aspects of the measurement of ionising radiation. It is convenient to refer to them at this point. A substance which is radioactive is so because it emits radioactive ions into the surrounding atmosphere. It does so because it is subject to radioactive decay which is measured in disintegrations per second (dps). The original unit for measuring such radioactivity was the "curie" (Ci) which is based on the radioactivity of one gram of radium. This proved to be an inconveniently large unit of measurement and has been replaced by the "becquerel" (Bq) (1 Bq = 1 dps). 36. For scientific purposes it is also necessary to have units of measurement for radiation. This is achieved by measuring the number of ions produced in a unit volume of air. Such a measurement establishes the quantity of radiation passing through the air and, therefore, the quantity of radiation to which an interposed object is exposed. This measurement is known as the "exposure dose". It was originally measured in "roentgens". The relevant unit is now called the "coulomb/kg". 37. As might be expected, health physics, with its focus upon the question of damage to the human organism through ionising radiation, is concerned not only with measurement of the exposure of the human body to radiation but, more significantly, with absorption of the radiation into human tissue in various parts of the body. A measurement is therefore necessary of the amount of energy deposited by radiation passing through tissue. This measurement is known as the "absorbed dose". Absorbed dose was originally measured in "rads" being 0.01 joules of energy per kilogram (J/kg). The rad has now been replaced by the "gray" (Gy), 1 J/kg. 38. A further refinement of measurement of dose has been arrived at to take into account that some forms of radiation are more effective at producing biological damage than others. Alpha particles, whilst they present no significant risk when they impinge upon the body's outer surfaces, are hazardous when they are absorbed into the human body. Conversely, gamma rays readily penetrate the body's outer surfaces, but produce less risk of biological damage. Similarly, beta particles when absorbed into the body are less hazardous than alpha particles. These factors are taken into account by a measure of "dose equivalent". The original unit was the "rem" (rad equivalent man). This unit has been replaced by the "sievert" (Sv). The measurement of dose equivalent is of great significance in this case as there has been very considerable scientific study of the effects on various parts of the human body of exposure to radioactive substances. Such studies have involved considerations of dose received measured in rems or sieverts. 39. It may also be noted at this stage, that the human body is constantly exposed to ionising radiation from natural sources. Such radiation is referred to as "background radiation" and, as might be expected, the potential deleterious effects of radiation from nuclear sources can be considered in terms of whether the amount of radiation produced by those sources exceeds background radiation and, if so, to what extent. 40. It may be noted also that, prior to 1956, the question of the safe limitation of radiation doses to human beings had been the subject of considerable attention. The present organisation, at an international level, which assumes responsibility for the making of recommendations as to permissible exposure to ionising radiation is the International Commission on Radiological Protection (ICRP). This organisation was active in the field prior to the commencement of the nuclear testing at Maralinga and elsewhere. In 1955 the Commission had established a recommended limit for radiation dose received by workers in the field as being 0.3 rem per week. It is clear that the Radiological Safety Regulations 1956, referred to above, took account of and reflected the recommendations of the Commission. As indicated already, it is not suggested on behalf of the applicant, that these Regulations were otherwise than a proper response, in 1956, to the perceived hazards of radiation resulting from the proposed nuclear tests. In fact, the Regulations set out in some detail, in sets of scientific formulae, the permissible radiation exposure levels in active areas for external radiation exposure (beta and gamma) and for internal radiation exposure through alpha-emitters and beta/gamma emitters. 41. Where the hazard was seen to be related to the inhalation, ingestion or injection of radioactive isotopes the Regulations laid down a maximum permissible level of contamination of the ground surface. This took account of the obvious fact that, after fallout, contaminants would exist at ground level from which they could rise to a level where they might be ingested or inhaled as a result of disturbance by natural forces such as wind gusts or because of work being done in the area. Measuring devices known as "cascade impactors" were used to monitor the presence of radioactive contaminants in the air. These devices were in use in areas where personnel were working during the inter-trial period preparing sites for the Antler series. No criticism was levelled at these instruments other than a general observation made by Mr Robotham, a health physicist called on behalf of the applicant, that they "had limited value because of the relatively small volumes sampled compared with the size of the area involved". THE APPLICANT, HIS SERVICE AT MARALINGA AND SUBSEQUENT HISTORY 42. The plaintiff was born on 23 October 1929. He left school in 1945 having failed to obtain the intermediate certificate. Thereafter he worked as a process worker, a tramways conductor and a fitter of industrial sprinkling systems. On 28 February 1956 he joined the Australian Army, performed his basic training at Kapooka and then volunteered to go to the Maralinga range. He was aware that it was a testing site for atomic bombs but, he said, he received no specific training by film or otherwise in relation to atomic explosions. He arrived at Maralinga on 8 March 1957 and performed duties as a sapper in the Engineers until finally leaving the range on 6 November 1958. Accordingly, he arrived during the inter-trial period and left in the month following the completion of the Antler series. His work was of a labouring kind in the preparation of sites and in their subsequent dismantling. I shall refer to this in more detail later. 43. After leaving Maralinga and engaging in some army exercises in Queensland he served in Malaya from September 1959 to November 1961. In 1961 he received treatment for an abscess on the liver. At that time he was a very heavy drinker. He also smoked tobacco to excess. I am satisfied that he had and continued to have a drinking problem and that he continued to be a heavy smoker. 44. He left the army in 1962 and thereafter had a variety of jobs, one of which was the fitting of sprinklers, an occupation he had followed previously. He continued this occupation until retirement on 2 June 1994. 45. Early in 1982 Cubillo was diagnosed as suffering from a grawitz tumour of the right kidney, also referred to in the evidence as a renal cell carcinoma. This was removed by operation at Westmead Hospital, Sydney, in March 1982, the operating surgeon being Dr Drummond. After recovering from the operation, Cubillo continued to drink heavily to the extent that his domestic life was severely affected. His wife left him in 1983. He had also been a very heavy smoker up to the time of the operation. 46. As advised, Cubillo had regular medical checkups in relation to his kidney cancer and its possible recurrence or spread. One of these resulted in his being admitted to Westmead Hospital in January 1990 for suspected lung cancer. A biopsy was performed and thereafter a tumour was removed from his right lung which was a metastasis from the original grawitz tumour. There was no evidence of any other tumour and it was hoped that he would have no more problems. In 1991 he developed what he has described as a lump under the right collar bone. It appears that it was provisionally diagnosed as a recurrence of his cancer problem. Arrangements were made for its removal but, in fact, it dispersed of its own accord. He has had no recurrence, with the result that any continuing cancerous condition appears to be in remission. His retirement in 1994 was not related to any health problem claimed to be associated with his service at Maralinga. 47. It is clear from the medical evidence, and it is accepted by Cubillo, that he has had a long history of alcoholism and that his memory and concentration have been severely affected by it. This has manifested itself in the case by his experiencing serious difficulty in recalling many aspects of his work at Maralinga. I consider that he was basically an honest witness, not seeking to mislead the Court, but that these problems have considerably affected the weight of his testimony. THE APPLICANT'S CASE 48. As already indicated, it is claimed that Cubillo's renal cell carcinoma resulted from his being wrongfully exposed by the Commonwealth, as his employer, to ionising radiation at Maralinga. At the end of the case the claimed exposure was to the isotope plutonium 239, the claim in respect of polonium 210 having been abandoned. It is asserted that the renal cell carcinoma was occasioned by the introduction of plutonium 239 into his body as a result of inhalation or, more probably, ingestion. The inhalation was said to have resulted from the radionuclide becoming suspended in the air he was breathing as a result of his working in dusty or windy conditions in contaminated areas. Ingestion was said to have occurred as a result of his wiping contaminated dust or sand across his face and mouth whilst removing perspiration when working in similar conditions in similar areas. It was also claimed to have occurred through eating radiation contaminated food in such areas. 49. The work being performed fell into three groups. First, it was alleged that exposure occurred whilst he was working as a sapper in areas described as "laneways". These areas were in the vicinity of the ground zero sites for the Antler series. They were being constructed for the siting of instruments and associated cabling to be used in the recording of data to be obtained from the test firings. The work consisted of the digging of trenches which, in general, radiated out from the ground zeros. This was physically hard and dirty work, carrying risk of inhalation or ingestion. In conjunction with this work, fencing was erected consisting of the forcible placing of "star-pickets" into previously drilled holes. 50. Secondly, exposure was alleged in relation to work done by Cubillo in relation to either the dismantling of an observation tower or the retrieval of the dismantled parts from a contaminated area. 51. Thirdly, it was claimed that inhalation or ingestion occurred whilst Cubillo was engaged in a sweeping operation conducted at the Taranaki site after it had been contaminated by fallout from the Biak explosion. It was asserted that ingestion of plutonium 239 would have occurred when, in the hot and dusty conditions that prevailed, Cubillo removed his respirator in order to wipe perspiration from his brow and face, the wiping operation being performed by his hand when clothed in a glove, the surface of which had become contaminated by radioactive material. It is also alleged that inhalation of radionuclides would have occurred in those circumstances. 52. Fourthly, reliance was placed upon the assertion that Cubillo, along with other sappers, had cooked and eaten meals whilst working in contaminated areas. The food consisted of meat cooked on shovels over open fires lit by the men. The shovels were used in contaminated areas and were likely to have been contaminated by sand containing plutonium 239. 53. These claimed exposures were alleged to be in breach of the Commonwealth's duty of care as an employer. The ultimate statement of the acts and omissions relied upon in this regard were as follows:- "i. Failure to ensure that all personnel on the range were aware of areas where there could be a risk to them from alpha emitters when eating. ii. Failure to warn the Applicant of 'red areas' and of the risk to him from alpha-emitters when eating. iii. Causing and/or permitting the Applicant to eat in areas where there was a risk to him of damage from plutonium. iv. The vicarious liability of the Respondent, Hutton, in failing to supervise the activities of personnel under his direction and control to see that work was not done in areas where there was a risk from ingestion or inhalation. v. Failure to supervise the Applicant and to ensure that all personnel involved in the Taranaki sweep-up wore respirators during such operation. vi. Failure to warn personnel involved in the Taranaki sweep-up, including the Applicant, of the danger of removing respirators in the course of such operation. vii. Failure to ensure that proper control procedures (wearing respirators; and advice as to danger areas) were maintained when personnel including the Applicant were carrying out activities which involved a risk by way of inhalation or ingestion of radio-active materials, specifically plutonium. viii. Causing and/or permitting the Applicant to carry out work activities when there was risk to him of damage from inhalation or ingestion of alpha emitters, specifically plutonium, and proper control procedures were not maintained." 54. The reference to "the Respondent, Hutton" (he was not in fact a respondent to the application), was a reference to the Lance Corporal, referred to for the most part in the evidence as "Lance Corporal Woodleigh". He was in charge of one of the sapper work parties engaged in work in the laneways. He gave evidence to which I shall refer later. 55. Apart from relying upon these particularised breaches of the employer's general duty of care, counsel for the applicant made submissions based upon the principles expounded in cases such as Birkholz v R J Gilbertson Pty Limited (1985) 38 SASR 121 and McGhee v The National Coal Board (1973) 1 WLR 1. I shall refer to these submissions later. 56. It is plain that, however the applicant's case is put, he must establish on the balance of probabilities, that he was, during his work at Maralinga, exposed to the risk of inhaling or ingesting plutonium 239 in an amount sufficient to constitute a danger to his health. This in turn necessarily leads to the inquiry whether the applicant has established to the same standard that he was required to work in areas where that risk existed. As this is a fundamental question in the case, it is convenient to deal with it at the outset. DID THE APPLICANT WORK IN AREAS WHERE HE WAS EXPOSED TO THE RISK OF INHALING OR INGESTING PLUTONIUM 239? 57. It will be remembered that the Regulations spoke of active areas being designated as "yellow" where there was a serious risk of inhalation or ingestion requiring full protective clothing, and "red" where there was slight risk of inhalation or ingestion requiring protective clothing to be worn only on the recommendation of health physics personnel. The question must, therefore, be asked whether the evidence establishes that Cubillo was required to work in areas that could properly have been designated as either yellow or red. 58. The sweeping-up operations at the Taranaki site merit separate consideration. I shall refer to them later. (a) Work in the Laneways and on Towers 59. The applicant's evidence relating to work in other allegedly active areas consists of certain statements in the health physics reports of the inter-trial period and associated correspondence, the testimony of Cubillo and lay witnesses called on his behalf, being fellow sappers, and the evidence of Mr Robotham, a health physicist. Also, some evidence was given by Dr Kefford to which I shall refer later. Mr Davy, a health physicist gave evidence on behalf of the respondent. Further evidence was given for the respondent by Mr Flannery, the security officer at the range, and Major McDougall, who had been in charge of health physics during the Antler series. Some film badge and dosimeter records were relied upon. Also the evidence of Mr Moroney, a physicist, given in other proceedings, together with maps prepared by him, was admitted in these proceedings, Mr Moroney having recently died. 60. It is impossible to establish from the evidence in the case exactly where Cubillo performed his work in the forward area. The records indicate that he was one of the sappers involved in the general engineering work required in relation to the sites for the explosions. However, there are no records in evidence indicating what the daily duties of the sappers were and the areas in which those duties were performed. Film badge and dosimeter records provide some assistance and are referred to in the health physics testimony. 61. There was a suggestion in the evidence that labouring and fencing work in the laneways was conducted not only in the inter-trial period but also between the explosions in the Antler series, however, I am satisfied that this suggestion is not made out on the evidence. Apart from the sweeping-up operation at Taranaki, I find it impossible to determine on the evidence what work, if any, was done by Cubillo in the forward area let alone any active areas after the commencement of the Antler tests. There is, however, a serious question as to whether he was required to work in yellow or red areas in the inter-trial period after his arrival at Maralinga and before the first explosion at the Tadje site. 62. On behalf of the applicant, heavy reliance is placed upon certain statements in the health physics reports issued by Mr Turner in this period. It is, therefore, necessary to set out relevant parts of those reports. 63. In his report of December 1956/January 1957 Mr Turner deals with health control in the forward area after the completion of the Buffalo trials. He speaks of the establishment of a "Yellow Boundary" and the issuing of a "Health Control Map" in the following terms:- "Yellow Boundary:- A continuous length of yellow tape has been erected from a point due west of Apu, south around Breakaway to Pom-Pom and across towards Kite. The tape is staked to empty cable drums at intervals of about 25 yards. It is intended in the near future to extend the yellow tape for 2.5 miles along the Kite-Nawa road. Map:- Two thousand 8in x 13in copies of a Health Control Map have been printed and are now issued to all personnel proceeding north of Roadside. This map shows the principal roads and work sites in relation to the yellow area." 64. I am satisfied that this "Map" is the basic map to which I referred earlier, which should have found its way into the hands of all personnel entering the forward area and have been placed upon the noticeboard at Roadside. It is basically the same map which has been reproduced as Schedule 1 to these reasons. It is the same as map 2 of Exhibit 4. 65. It is clear that, at least in January 1957, Mr Turner had established a demarcation line indicated by yellow tape and was intending to extend it for a considerable distance. The area to the north of this tape was designated the "yellow control area". The report refers to a fairly elaborate procedure for the issuing of permits to enter this area and for the supervision of the area from a tower manned by peace officers whose duty was to watch vehicles and personnel proceeding towards that area through the forward area. They were provided, by telephone, with relevant information enabling them to check on the legitimacy of people or vehicles moving in the area. The report also refers to the system of contact with the roving patrol vehicle, to which I have already referred, and the procedures for dealing with unauthorised intruders. In this regard, I am satisfied by the evidence of Mr Flannery that, although these procedures were in place, it was never necessary to use them. 66. The report also refers to the taking of measurements of radioactive decay of fallout from the Buffalo tests. It was also noted that air sampling had produced an indication "of a slight amount of activity at Gona" in the dust cloud arising from the work of heavy machinery. However, cascade impactor readings indicated that there was "insufficient activity to represent a health hazard". 67. In the February 1957 report Mr Turner indicated that the yellow tape had now been extended 2.5 miles along the Kite-Nawa road. It also spoke of the erection at this stage of the warning signs to which I have already referred. The report also speaks of radiation surveys being carried out. No submissions have been made to me based upon this material. It is indicative, however, of the level of supervision being maintained in relation to the presence and extent of radioactivity following the Buffalo series. It may be noted that air sampling by means of cascade impactors had been conducted in the crater areas at the ground zeros of Breakaway and Marcoo. Calculations were made on the basis of breathing air for 56 hours per week in these areas. It was found that there was no inhalation hazard for normal winds. The further comment was made that: "A hazard may exist for strong winds, but under such circumstances, the dust cloud that is created from non-active areas usually deters people from approaching the forward area. For the Breakaway region, it would appear that by the end of 1956, most of the loose activity had been blown away". 68. In the March report the following statements appear which are relied upon on behalf of the applicant: "Active Area Radiological Safety Regulations, Maralinga, (RSRM 56 (5)) section 3.2.1. states that a non-active area has no detectible loose activity. The maximum permissible level of loose beta, gamma contaminations is 6 x 10 -8 uc/cm2 (section 2.4.3.). Unless concentrated this level cannot be detected by a geiger counter as the counting rate is an extremely small fraction of the natural background. On D4 and D4 + 1 day, the edge of the fall-out was determined as being 0.04 miles south of Pom Pom 0.19 " " " J7 0.32 " " " J8 0.5 " " " J9 0.7 " " " Nawa Accordingly, Health Physics barriers were erected on D4 + 2 day across the main roads to One Tree and Marcoo at the above points. On D4 + 8 day, they were found to have been moved to Kite and J7 respectively. The barriers were replaced in their earlier positions. On D4 + 17 day, U.K. representatives confirmed the moving of the yellow boundary to the J7, Kite, Nawa line. This meant that an active area existed below the yellow boundary. Section 3.2.2. of RSRM would require that this area be declared a Red area. However, with the hundreds of men required in this area under difficult labour conditions, it would be quite beyond the capabilities of the present Health Control facilities to cope with such an area. The future sites having already been selected within this potential Red area, there was little that could be done about the matter. The control methods chosen were:- (a) limiting movement in the forward area to the south of Mina if at all practicable. (b) when a large body of men had to work in the area, cascade impactors were set up and the samples counted every second day, as a check on any inhalation hazard. (c) meals were eaten at Mina. (d) in the case of Tadje, the topsoil was removed. Gona A survey on 3 Jan 57, of the Gona area showed that the gamma intensity varied from 8 c.p.s. on the southern edge to 20 c.p.s. on the north side. The beta component was about equal to these values. As the activity was confined to glass beads of about 1mm diameter, and it had been shown that these beads were insoluble in either water or HCL, then it was decided to forego the removal of top soil. By 31st March, Gona was more than half completed and only a few workmen remained on the site. Tadje A survey on 22nd Feb. 57 of the Tadje area showed that gamma radiation varied from 23 to 40 c.p.s. and beta plus gamma varied from 35 to 150 c.p.s. Despite the insoluble nature of the fall out beads, it was decided that this activity warranted the removal of the top soil over a radius of 55 yards and also from a 60 foot wide access strip. The area was cleared on March 8th, after which there was no evidence of any remaining surface contamination. A cascade impactor was maintained at Tadje for the rest of the month. By March 31st, the preliminary work was completed and the foundations were laid. Biak Work at Biak will commence early in April. A survey of the Biak area on March 20th showed that there is no beta activity on the ground and the background is about 2 c.p.s. of gamma." 69. The reference to "D4" is intended to indicate the nuclear test at the Breakaway site. The "glass beads", although being part of the fallout from the previous tests, are not of direct significance in this case. They contained no plutonium 239 and were not a relevant inhalation or ingestion hazard. 70. It clearly appears, however, that as at March 1957, Mr Turner was of the view that the moving of the yellow boundary to the J7 Kite-Nawa line had exposed an active area to its south, which could properly have been described as a red area. It was not possible to employ the normal health control facilities for the reasons that he sets out. Presumably this would have involved the issue of some form of protective clothing regarded as suitable by health physics personnel. It may be noted that there is nothing in the case indicating what that would have been. As inhalation and ingestion risk in a red area was said to be slight, it does not seem likely that workers in the area would have been issued with respirators as a matter of course. It is also to be noted that steps were taken, as set out, to check on inhalation hazards. There is nothing in the report to indicate that any such hazards were detected. There is also a question whether, in later reports commented upon by Mr Davy, Mr Turner in fact changed his earlier view as to this area. I shall consider this when discussing Mr Davy's report. 71. The applicant relies upon this part of Mr Turner's March report as an indication that Cubillo, having arrived on 8 March, was required to work in a red area in circumstances which constituted a risk of inhalation or ingestion of alpha-emitting radionuclides, specifically, in light of the elimination of polonium 210 from the case, the isotope plutonium 239. 72. In the June 1957 report Mr Turner speaks of the "rocket lanes" having been completed and the dismantling of Apu and Katu towers being about to commence. From other evidence it appears that the rocket lanes would have been constructed in the yellow area. They contained cables designed to conduct electric current to ignite rockets which were positioned so that, after firing, they would leave atmospheric trails which would provide a backdrop to the nuclear explosions. It appears that their firing points were north of the Antler ground zeros and consequently in the yellow control area. It is apparent from this report that personnel working in the rocket lane areas would have done so under health physics supervision with health physics protective clothing. It may be noted that the official records kept of the readings of Cubillo's film badges indicate that he was working in the yellow area for some days in May, June and August. Gamma doses of 0.13 and 0.02 rems are recorded for these periods. 73. Reference is also made in this report to the lookout tower having been moved to Tadje with instructions being given to the relevant peace officer "to keep a close watch on movement in the vicinity of the yellow boundary which can be seen clearly from beyond J9 to beyond Biak". The yellow boundary had itself been adjusted, presumably to take account of the contraction of radioactivity. 74. The July report indicated that the dismantling of the Apu and Katu towers was continuing after which they were to be decontaminated. There was also reference to the fact that "owing to persistent westerly winds the yellow boundary had to be withdrawn 100 yards from Breakaway towards Tanka". The level of activity at the new boundary was "between 100 and 200 counts per second on a 1320 monitor" (a form of geiger counter). It may be noted that this report contains a detailed analysis of the fallout from the Breakaway explosion. 75. It may also be noted that the report of the Range Commander, Colonel Durance, to the Chairman of the Atomic Weapons Test Board of Management on the completion of Operation Antler stated (inter alia) that "all work required to be ready for the beginning of the operation was completed and during the operation the Field Engineer Troop performed 44,000 man hours in assisting the Scientific Group". This group included the contingent of Australian Engineers. It lends weight to the finding that I have already made that the construction work in which Cubillo was engaged was completed before the commencement of the test series and that the brushing operation of the Taranaki site was, so far as this case is concerned, the only significant event thereafter. 76. In addition to the material from the March report set out above, the applicant also relies upon the contents of a letter from J.F. Richardson, Acting Director of the Commonwealth X-Ray and Radium Laboratory, to the Secretary of the Department of Supply. The letter is dated 1 May 1957. The letter reads as follows:- "1. I refer to your memorandum 6021/1/141 of 15/4/57. Attached to this memorandum was a copy of one to you from the Range Commander, Maralinga. 2. In this memorandum, the Range Commander drew attention to certain apparent inconsistencies between the Radiological Safety Regulations (RSRM/56(5)) and a supplementary set of instructions issued by the United Kingdom Health Physics Group during Operation Buffalo. Further, the Range Commander asked:- (a) that he be authorised to proceed with work on sites in the forward area; and (b) that he be assured that no one was being exposed to radiation hazard at these sites. 3. Comments on the interpretation of the regulations referred to are made in the attached memorandum. 4. After discussion between Mr. Cook and Mr. W. O'Connor of your Department and Mr. Richardson of this laboratory it was decided that Mr. Richardson should go to Maralinga to consult with the Health Physics Representative (Mr. Turner) on the points raised by the Range Commander and on any other matters relevant to Health Physics and Health Control on the Range. 5. Mr. Richardson was at Maralinga from the 24th to 26th April. During this period he had fruitful discussions with the Range Commander and Mr. Turner. Mr. Turner arranged a tour of the forward area and he and Mr. Richardson inspected the various bomb sites together. 6. As a result of this visit it is considered that:- (a) Apart from manpower, the arrangements for Health Control both in the forward area and at base are entirely satisfactory. The various aspects of Health Control have been described in the routine reports issued by the Health Physics Representative. Those whose duties take them to the forward area at present cannot proceed beyond Iwara unless in possession of an entry permit issued by the Health Physics Representative. This permit is only issued after appropriate enquiries and instruction. It is considered that in view of the rigorous and adequate control exercised over people entering the forward area, the legitimate possession of such a permit should be sufficient authority for the people concerned to proceed to their work in this area. Once such a permit is issued the Range Commander could be absolved from responsibility for the health of the individual (insofar as this may be affected by radiation alone) if this course was considered desirable. (b) The degree of hazard which exists at any place can be determined only by Health Physics officers using appropriate instruments. It is considered highly undesirable that work be done in areas which cannot be classified as non-active as defined in RSRM/56(5), section 3.2.1. Unfortunately, owing to the early changes made in the position of barriers defining Yellow Areas (of which changes Mr. Richardson was not aware before his visit to Maralinga) work has in fact been proceeding in active areas, for example, Tadje and Gona. The movements of the Yellow boundary and the action taken for Health Control at Tadje and Gona have been described by Mr. Turner in his report for March 1957. Mr. Turner has classed these areas as Red Areas, but as his assessment of conditions indicated that the hazard is slight no special protective clothing has been recommended for people working in these areas. Mr. Richardson supports this decision. 7. Owing to the proximity of the new sites to the Yellow Area it will shortly be necessary for work to be done in clearing lanes lying well inside the Yellow boundary. Mr. Turner has already arranged that this will be a 'Yellow Entry' and that the men working in this area will wear full protective clothing, including respirators, and will pass through Health Control in the usual way. 8. It is strongly recommended that every effort be made when selecting future sites that these be in areas which can be classed as non-active in accordance with section 3.2.1 of the RSRM/56(5). It is in accordance with this recommendation that the Duna site has been provisionally moved further east from that originally chosen to prevent work being carried on inside the Yellow boundary near Breakaway." 77. This communication is relied upon by the applicant's counsel as some indication that Cubillo was working in "active" areas, being the areas which Mr Turner had previously considered should have been classified as red after the movement of the yellow boundary referred to in his March report. It must be noted, however, that the result of this classification is much qualified by Mr Turner's reported assessment that the concomitant hazard was so slight that no special protective clothing had been recommended for workers in the area. In my view, this can only mean that the assessment of the inhalation and ingestion risks was such that the wearing of respirators was not required. 78. Mr Flannery, the Range Security Officer at Maralinga in 1957, also gave evidence in relation to the areas in which the engineers worked in the inter-trial period. He had no responsibility for health physics as such but, as his evidence indicates, he worked in close cooperation with Mr Turner in the implementation of health physics requirements. He had overall responsibility for the entry of personnel to the forward area through Roadside and for ensuring that only authorised personnel did so. He was also responsible for the overall surveillance of the activities of personnel whilst in the range area through the peace officers in the towers and the roving patrols. He visited the forward area himself on a daily basis. He had no responsibility, however, for personnel entering controlled radioactive areas, this being the jurisdiction of the health physics authorities. He was an impressive witness who was obviously most conscientious in the performance of his duties. I am satisfied that when he described the standards of safety and conduct at the range at Maralinga in 1957 as being "first rate" this was indeed his firmly held opinion. 79. Mr Flannery confirmed that the boundaries of the yellow or radioactive area were delineated by yellow tape which "was around every site of the Buffalo series except Kite which by that time would have lost any radioactivity". He himself did not see any preparation for the Antler series performed within the yellow area except for the clean-up at Taranaki. 80. Mr Flannery was familiar with the map showing the "yellow control area" hatched-in. It was part of his duties to provide this map in sufficient numbers to officers in charge of the various groups for distribution to personnel under their command. I am satisfied that he in fact provided the maps in accordance with his duties. It was not part of his duties to supervise their further distribution and he was, in those circumstances, unable to confirm that this was done. 81. He expressed the view that no construction work was done in "the instrument lanes" in contaminated areas, these being the areas within the hatched yellow control area on the map. He indicated, as was clearly the fact, that no red areas were designated before the completion of the Antler series. They were then marked out with red tape, the boundaries having been established after the Antler explosions through measurements made by health physics personnel. However, before the Antler explosions, although no red boundary was established, he was satisfied that, to his observation, no work was done inside the area which was hatched on the official map and described as the yellow control area. In his view, this area covered any area that could properly be described as a red area. 82. Mr Moroney, to whose evidence I shall shortly refer, delineated the boundary of the red area, as defined in the Regulations, on Map 7 of Exhibit O, as at July/August 1957. Mr Flannery was satisfied that the red area as so defined by Mr Moroney fell within the boundaries of the hatched yellow control area of the map (Map 2 of Exhibit 4) from which he and security personnel under him worked in performing their duties at the range. 83. It appears that all the sites for the Antler series fell outside, that is to the south of, the boundary and were, therefore, in Mr Flannery's opinion outside any area which could properly be classified as yellow or red within the terms of the Regulations. 84. A further witness called on behalf of the respondent, William Gordon McDougall, was a Major in the British Army in 1957. He was a health physicist by training and from 30 July 1957 to 22 October 1957 was in charge of health physics at Maralinga, having taken over from Mr Turner who had been in charge in the inter-trial period. Mr Turner became his deputy during the British supervision of the Antler test series. During his tenure of office there was a cessation of monthly health physics reports but an extensive and comprehensive report (Exhibit N) was made by him at the conclusion of his tour of duty. Under the heading of "Takeover of the Range" the following appeared:- "Responsibility for HP control of the range was assumed on 15 August, 1957. The Yellow Area remained as in the inter-trial period. It consisted of the area bounded by and including Central Street, Fifth Avenue, East Street and the Nawa-Kite road with the extension to the south-west to include Breakaway and Apu. Mr. Turner had recorded the work done on the range in the inter-trial period. No airborne hazard existed. A gamma dose-rate in excess of 7.5mr/h existed only in the immediate vicinity of One Tree, Marcoo and Breakaway craters. The beta activity in the Yellow Area was fixed almost wholly in large insoluble particles varying in weight from 0.03 mg to as much as 82 mg. It was noted towards the end of the trial that the glazed area of Breakaway was tending to break up into a fine dust when walked or driven upon. It was clear that the Yellow Area did not in general present a serious hazard. With the exception of the crater areas it could have been classified as Red. As the range staff had become accustomed to working under these conditions, and as it was likely to become seriously contaminated in the near future, no alteration was made." 85. Mr McDougall identified the hatched area on the second map in Exhibit 4 as correctly depicting the official yellow area at the time he took over. He said that at that time there were, within that general area, three small areas which could properly have been described as "yellow". These areas were around the ground zeros of the Buffalo series. They would have been "a matter of a few hundred yards around each". He indicated that all the intended sites for the Antler series were in fact below the hatched area on that map, although he stated that some of the work on the instrument lanes must have been "very near the edge of it". 86. Major McDougall had not been aware of Mr Turner's comments in his March health physics report. At the time he arrived at Maralinga the yellow boundary was "the J7 Kite and Nawa line". He also said that "it was implicit when you only lay down a yellow boundary that almost inevitably there will be a red area on the other side of it". I take this, however, as being in the nature of a general comment. It is clear from Major McDougall's other evidence that at the time he took over the range from Mr Turner, the boundary referred to could more properly be regarded as the boundary of a red rather than a yellow area within the meaning of the Regulations. 87. Mr Moroney's evidence must also be considered in this context. Mr Moroney was a nuclear physicist. During the Antler series he acted as Joint Scientific Secretary for two Australian committees formed in relation to the tests. These were the National Radiation Advisory Committee chaired by Sir MacFarlane Burnett and the Atomic Weapons Test Safety Committee chaired by Professor Ernest Titterton. In that capacity he went to Maralinga on 9 September. He witnessed the three firings in the Antler series with intermittent returns to Sydney. Thereafter, he maintained a professional interest in Maralinga, returning on a number of occasions in relation to other trials and the clean-up activities on the range. 88. Prior to the Antler series he visited the ground zeros for the Buffalo series. He "approached them to a reasonable distance and looked at them, with appropriate health physics protection and instrumentation". He also visited the three Antler sites which were all complete at that time. Mr Moroney prepared a series of maps showing the situation (inter alia) in relation to radioactivity on the range at various times. These maps are Exhibit O in these proceedings. Map 6 is entitled "Health Control Maralinga Forward Area" and dated February 1957. It is in effect basically the same map as Map 2 of Exhibit 4. However, Mr Moroney has indicated on it the position of various warning signs to which I have already referred, and has also depicted the position of the yellow tape which marked the boundary of the active area. This followed the irregular south western boundary of the hatched area and continued in a straight line eastwards along the Kite-Nawa road. Mr Moroney actually saw the yellow tape in position when he arrived in July. 89. The next map, Map 7, depicts the radioactive area which, in Mr Moroney's opinion, remained from the Buffalo tests as at July/August 1957. This map takes into account the classification of areas into red and yellow. By that time the yellow areas had contracted to quite small circles around the sites of the Breakaway, Marcoo and One Tree ground zeros. The line of the yellow tape had become, in Mr Moroney's scientific opinion, the boundary of the red area. Consequently, the area described on the official map as the yellow control area had become, for practical purposes, a red area with its outer boundaries along the line of the yellow tape. The whole of the Antler sites were outside these boundaries and, consequently, were not within an area that could be described as carrying even a slight risk of inhalation or ingestion of radioactive material. 90. Against this background I now turn to consider the evidence of Mr Cubillo and his lay witnesses. I have already noted the problems in relation to Mr Cubillo's memory. He is not able to throw a great deal of light on the areas in which he worked. He remembered that Lance Corporal Woodleigh used to send men out to do different jobs which involved them travelling by vehicle to an area where they were to work. As he said, "whoever was in charge just took us to the area". He was of the opinion that he worked in the area called Kittens, but that claim, as I have said, has been specifically abandoned. He did, however, have a fairly specific recollection of joining cables. It is possible, of course, that these were cables in relation to the instrument lanes leading to the Antler sites or, perhaps, the cables leading to the rocket sites. 91. He remembered digging post-holes using a drill attached to a compressor on the back of a 3 tonne vehicle and that, when using the drill, he would be on the ground beside it, the holes being fairly deep. The holes were drilled in the areas of Tadje, Biak and Taranaki. Sometimes he assisted in blowing holes in hard ground with explosives. The holes were in the areas already referred to as laneways. The holes that were drilled were for the placement of star-pickets. The areas that were exploded were to take instruments. He was in the charge of Sapper Moore who has since died. Mr Moore would indicate where the holes were to be dug or the explosives laid. Whilst doing this form of work in the laneways he would not wear protective clothing, nor would he go through the health physics caravan. 92. Cubillo gave evidence of eating meals in the laneways. Sometimes these meals were sandwiches, although it appears from the evidence that sandwiches were eaten when work was being done on the joining of cables. On other occasions he would join other groups who were working in the laneways for lunch. He said that meals of this kind were brought from Roadside in a box and consisted of meat and eggs which were cooked on a shovel over an open fire. The shovel would be one used for digging in the course of their work. The shovels were "fairly clean, all you had to do was just wipe the dust off". So far as sandwiches were concerned, they were obtained from the counter in the canteen at Roadside and were eaten out in the open or in the trucks they were working in. 93. When going into a radioactive area he went through health physics and was supplied with a protective suit, rubber boots and respirator, the suit having a hood. When wearing this clothing he would go out into the area where he understood nuclear explosions had occurred, but had no recollection of what he did when out there. However, he remembered that he was accompanied by a health physicist who was taking readings in the area they were going through. 94. He also remembered going out on a truck to retrieve a camera tower. He went from Roadside, but does not remember where he went to. He does not remember wearing any protective clothing on this occasion. However, he had an instrument which appears to have been a geiger counter. When they arrived at their destination there was a dismantled tower and wooden platform lying on the ground. They ran the counter of over it and "the needle just went right across, straight over". They found a little bead "about the size of a pinhead" which appeared to have caused the counter to react in this way. He brushed it off the platform and loaded the platform onto the truck. It was very hot and dusty and the dust would stir up as they walked. It is reasonable to assume that one of the yellow area gamma dose readings referred to earlier was recorded on this occasion. He had a vague recollection of dismantling a camera tower on another occasion. He couldn't say where it was except that it was in the forward area. He had no recollection of Mr Chasty, another witness in the case, being present. I consider that I cannot attach any weight to this recollection. 95. So far as his claim to have worked in the instrument lanes leading up to the sites of the three Antler explosions are concerned, Cubillo is supported in broad terms by Messrs Chasty, Abercrombie, Hutton and Cervetto. I am satisfied that Cubillo and the others worked hard in the open in conditions that were often dusty and in which they would quite frequently wipe perspiration from their face in circumstances where they may have conveyed dust and dirt to their mouth. I am also satisfied that from time to time they would have inhaled some quantities of dust. 96. So far as the allegations of regular eating of meals cooked on dusty shovels over open fires are concerned, I find myself far from satisfied as to these activities. It is unnecessary to consider the evidence in any detail. It suffers from the twofold vices of fading memory over the years and also suggestibility through discussion of the evidence by the witnesses among themselves. It appears that some slight evidence as to this activity was given before the Royal Commission. It has now become a major feature. 97. Mr Flannery, who gave very balanced evidence, regarded this as one of the "myths" of Maralinga. He pointed out that the lighting of fires in the open was expressly forbidden, unless with permission, by the Regulations. It is also clear from his evidence that any fires so lit would have been, for the most part, clearly visible from the watchtowers with the result that action would have been taken to prevent it. 98. I was not impressed by evidence given by Mr Hutton to the effect that this activity was actively encouraged and aided by the officer in charge. Neither the content of the evidence nor the manner of giving it impressed me. I think the truth of the matter is that this activity may have occurred on occasions but was by no means a regular thing. Like Mr Flannery, I am unimpressed by claims that these men who were subject to military discipline and were members of the Australian Army behaved like leaderless rabble, regularly acting in breach of the Regulations. 99. I have considered Mr Chasty's evidence that Cubillo was working with him on an occasion when a tower was being dismantled in circumstances where protective clothing was being worn. On this occasion, according to Mr Chasty's evidence, both he and Cubillo removed their respirators because of the heat. It is possible that Chasty was working on the tower at Apu which would have been in a yellow area, requiring the wearing of protective clothing. He says that Cubillo was working with him. Cubillo has no recollection of this. Mr Chasty was mistaken as to other matters, in respect of which he had claimed a clear recollection. He was clearly wrong in asserting that he was not issued with a film badge and equally wrong in asserting that he came to Maralinga on the same train as Cubillo. I am satisfied he was an honest witness but, that, over the period of time involved, his memory is not reliable. He also demonstrated suggestibility. I am not persuaded by his evidence that Cubillo in fact worked on the dismantling of any tower in the circumstances deposed to by Mr Chasty. 100. In the upshot, so far as this aspect of the case is concerned, I am satisfied that Cubillo worked in the instrument laneways leading to the Antler sites and that he did so in conditions where dust could be stirred up through the activities of the men, which dust could, in some circumstances, be inhaled or swallowed. I consider that on occasions which were comparatively rare he ate meals cooked in the field and that on other occasions he ate sandwiches which he brought with him from Roadside. I am satisfied that he was unaware of the designation, in terms of the Regulations, of the areas in which he was working and that he was not issued with any protective clothing for use in that work. He relied upon those in charge of him to take any necessary steps for his safety in relation to radiation hazards. I am also satisfied that there were occasions when he entered radioactive areas having passed through the health physics procedure and having been issued with appropriate clothing. I am satisfied that on those occasions the group he was with was accompanied by a health physics representative, this being the established procedure. On one such occasion he assisted on the retrieval of dismantled portions of a camera tower and had the experience with the geiger counter to which I have referred. 101. In relation to his work in the laneways, the question whether he was thereby exposed to a radiation hazard through the inhalation or ingestion of plutonium 239 must be determined by assessment of the expert evidence in the case. I shall deal with this later. Before doing so, it is necessary that I consider the evidence relating to Cubillo's involvement in the sweeping-up operation at Taranaki. (b) Taranaki Sweep-up 102. Hitherto I have been considering areas which may have been affected by radiation hazards introduced by the Buffalo explosions. The sweeping-up operation at Taranaki was occasioned by the explosion at Biak during the Antler series. It appears that fallout from this explosion unexpectedly occurred over the site where the Taranaki test was to take place. Accordingly, it was necessary that the fallout be cleared away so that the final preparations for the Taranaki explosion, which was to be a balloon firing, could take place. This operation was performed whilst health physics was under the control of Major McDougall. He deals with the operation at some length in his report (Exhibit N). First, I shall consider Cubillo's version of the clean-up operation. 103. Cubillo said that he went to the contaminated area "to clean up radioactive wastes so that scientists (could) work in there". He went through health physics and was issued with protective clothing being "the lot, respirator, protective clothing". After leaving the health physics facility he entered a vehicle that had a circular broom attached to it. This was inside the Taranaki area. He said that he was told that "once we got a reading of 0.3 to get out". He had a film badge and dosimeter, the latter being carried somewhere in his overalls. In relation to what occurred in the Taranaki area he was asked the following questions and gave the following answers:- "When you got inside the Taranaki area as you have referred to, what work did you do?---Well, we were told which part to sweep, it was highly radioactive and the soldiers had had to work in there and that's when we were told once we got a reading of point 3 to get out and being so hot - - - Well, just pausing there, please, Mr Cubillo. What did you actually do when you were inside that area?---I'd be watching the broom and make sure nothing goes wrong. The broom you have described as a circular broom?---That's right. Was attached to what sort of vehicle?---It's a Land Rover. Then the Land Rover would go over a particular area?---That's right. What would the broom do?---Sweep the waste edge of it of that certain area and then we'd go back in - - - Where would it sweep to?---Well, an area they just told us to sweep, sweep it over. Could you see what you were sweeping?---Not for very long because it was that hot, with the respirator on you couldn't see, you were sweating like a pig so you'd have to take it off because you'd wipe yourself you'd be sweating - wipe yourself with the back of your hands. Just a minute. You say you can recall taking your respirator off?--Oh yes, it was so hot. And doing what once you - - -?---Once you got the respirator off I'd be sweating so much I'd have to wipe the sweat off my brow, face - - - With the back of your hand?---That's right. In a manner similar to what you already indicated?---Mm. (Yes) When you did that, did you have anything on your hand when you wiped your face?---Gloves. You had to have gloves on. Did you do that work for a period of time?---We weren't there for that long, say half hour, could have been more, but - - - How long did it seem to you?---Well, time just got away, but it seemed to me about half hour, could have been more. On an occasion on which you removed your respirator, did you observe a reading on what you have referred to as the dosimeter?---Mm, that's right. What did you observe as the reading?---Point 3. What did you do when you observed that?---Just packed up and went back to health physics." 104. He gave the following evidence as to what occurred upon his return to the health physics caravan:- "When you went back to health physics, what happened there?---We were checked before we went into the caravan. They took the gloves off, took the respirator off, took the hood off, just checked us with a counter. Then we'd go in, strip off, have a shower. How many showers did you have?---Well, they said, once we had to shower, we came back out. They had a machine there that checked your hands, your feet, and if you had a reading, you had to go to wash basin, use hands and soap, clear yourself. Do you recall what happened to you on that occasion?---As far as I remember, I just went into caravan. I only remember showering the once. My hands were clean. I might have washed a couple of times and then that was it, got changed and left." 105. In answer to further questions in relation to the sweeping-up operation, Cubillo said that it was performed using a circular broom that was pulled along behind the Land Rover and that the broom "just rolled around". He further stated that when he took his respirator off he was sitting at the back of the Land Rover watching the broom revolve. The Land Rover was open at the rear and sides and, perhaps, the top. 106. It is difficult to evaluate Cubillo's evidence as to the Taranaki sweeping-up operation. His memory, in general, could only be described as poor and it is difficult to place great reliance upon matters that he claims to recollect specifically. Mr Cervetto, whose memory I would regard as generally being more satisfactory, insofar as it had not been affected by any drinking problem over the years, was present at the sweep-up. In contrast to Cubillo, however, he has only the vaguest of recollections of being present on the occasion. He can provide no specific recollections in any way comparable to those that Mr Cubillo now feels that he has. Moreover, Cubillo's recollection has, apparently, undergone some changes with the passage of time. In a statement made for the purposes of the Royal Commission in 1984 he expressed the view that he was riding on a tractor and that the reading obtained on the dosimeter was a "high reading". He appears to have made no mention of the reading being "0.3". It does not appear that, before this litigation, he had ever claimed that a reading as high as 0.3 had been observed by him. In fact his film badge record for the day in question indicates that he was exposed to no more than 0.13 rem. I am not satisfied that he ever observed any dosimeter reading of the order he now claims, although I accept that he now believes that he did. 107. Some problems also arise in relation to the particulars supplied in the course of the litigation. In answer to questions relating to the Taranaki clean-up, Cubillo's solicitors provided the following information to the solicitors for the Commonwealth:- "Our client was required to go through the health physics caravan, where again, he was required to put on protective clothing. Our client then went to the bomb site. At the time, our client would have been driven in a land rover to the Taranaki site at the back of the land rover. When our client arrived at the Taranaki site there would have been a concrete platform of approximately 100 yards in diameter. Our client was then required with the other personnel present, in turn to drive the land rover, which had circular brooms attached to the back, and sweep the dust off the concrete platforms. Our client would have performed these duties just prior to the Taranaki explosion." 108. These particulars were supplied on 21 July 1994. They indicate, quite clearly, that contrary to the evidence he gave as set out above, he was required to drive the Land Rover during the sweeping process, a task which was undertaken in turn with other personnel. It is a very different picture from that portrayed in his testimony, namely of sitting, in an exposed position, on the rear of the vehicle during what would have obviously been the most dusty part of the operations. Whilst some allowance may, perhaps, be made for some failure of communication between Cubillo and his solicitor during the course of giving instructions as to this matter, the discrepancy is, however, in my view, not one of merely minor significance. 109. Again, there are problems in relation to his assertion that he removed his respirator. There is no doubt that he was issued with a respirator and was required to wear it whilst working in dusty conditions in this operation. He, obviously, would have known that it was a part of the protective clothing issued to him for the purpose of the work he was doing. I simply do not accept that he or, indeed, any of the sappers would have been under any misapprehension as to why the respirator was issued or as to why it should be worn. Equally, I am certain that they would have known that in the interests of safety the respirator should not have been removed in dusty conditions. 110. Cubillo made a statement for the purposes of the Royal Commission. The statement has been tendered in evidence in these proceedings. Although it deals with what is obviously the sweeping operation with the circular broom and refers to the "high reading" on the dosimeter, no mention is made of any removal of the respirator during the course of the work. 111. Furthermore, in the particulars supplied to the respondent's solicitor, the removal of the respirator at the Taranaki sweep-up is referred to in the following terms:- "Whilst our client was sweeping the Taranaki site he would have taken off his respirator as it was too hot to breathe. Our client would have suffocated and would not have been able to see as the respirator would have fogged up." 112. Again, these assertions fall far short of the precise allegations given in Cubillo's testimony, which are set out above, and which are to the effect that he removed his respirator whilst sitting on the rear of the Land Rover amidst the dust of the sweeping operations because it was fogged with perspiration and extremely uncomfortable in the hot climatic conditions. The removal was, also, more or less contemporaneous with the reading of 0.3 on the dosimeter. The question is, of course, whether this recollection can be regarded as a true recollection rather than one which Cubillo has come to believe in the context of the case he brings. He does not, in general terms, evince a reliable memory. This now specific version is not corroborated in any way. The decision to leave the area must necessarily have been taken in consultation with the driver of the vehicle who has not been identified or called. The dosimeter reading is contradicted by the records. These are highly significant problems. 113. I am satisfied that this operation was by no means haphazard. It was an organised military operation under the supervision of the health physics team. The person in command of the work has since died. However, the whole episode is the subject of a comprehensive report by Major McDougall in Exhibit N. The relevant part of the report reads as follows:- "Round 2 was a tower burst at Biak. The firing was at 1000 hours on 25th September. Soon after firing it was clear from the lane surveyor's reports that an appreciable amount of fallout had descended upon Taranaki, which was the intended site for Round 3. The wide extent of the contamination resulted in a heavier call upon the Yellow vehicle fleet than had been anticipated. Fortunately the degree of contamination upon sites used on Round 2 was not high. All entries that were required were made without undue delay. The Yellow boundary was initially established from Marcoo, through a point 500 yd east of Kudat, to Boundary and included all areas to the north and north-east. It was subsequently established that fallout had occurred along the whole length of East Street to 25th Avenue. On D2 + 1 members of DC, RF and HP Groups started work in Taranaki. The first objective was to get the sheds assembled and as clean as possible, The second was to remove gross contamination from the road and compacted area. To this end the area was swept with rotary road brushes. The sweeping was continued on three subsequent days. It removed a considerable amount of fallout bodily from the road. The dust was collected and dumped. Due to the large area involved the gamma doses-rate was not materially affected. The amount of contamination detected upon vehicles and personnel who had been in the area was soon small. Whilst the actual sweeping was in progress the airborne activity in Taranaki was higher than at any other time or place in the trial. At D2 + 2 it reached a maximum of 0.04 tolerances. The brush operators clothing was heavily contaminated. The men involved in this task were changed daily. The maximum whole body dose received by them was 0.18 r. A thyroid count failed to reveal any measurable quantity of iodine-131. Everyone working in Taranaki wore a respirator when in the vicinity or downwind of the brushing operations. A member of HP Group was in the area to direct health control." 114. I note also that the evidence indicates that the ambient temperature at that time did not exceed 26 degrees C. 115. Reference is also made in the report to a check on airborne activity during the sweeping operations. This was conducted by the use of "Portable Air Samplers 1195" and "cascade impactors". Measurements taken by these means failed to indicate the presence of any significant activity. 116. Major McDougall described the operation of the cascade impactor. He said it was an instrument which basically took air around a number of corners at each of which the heavier particles in the air impacted upon a plate. After the air had passed around four corners it was drawn through a very fine filter. The material obtained at each stage or corner could then be subjected to geiger counter readings. This enabled a wide sample of airborne activity to be measured. Major McDougall indicated that the advantages of the cascade impactor were that "you can sort out those particles which are liable to be taken into the lung". He went on the say that a great majority of particles were very large and in fact "you couldn't breathe them into your lungs. You only really take something into your lungs if it's below 10 micron; a micron being a billionth part of a metre". 117. Major McDougall gave further evidence as to the Taranaki sweep-up in his oral testimony. In relation to the time spent by any one person in the performance of work in this operation, he said that the men were changed daily because of exposure to "a fair amount of radiation" and also because it was a very dirty job. He said "it was a very unpleasant job, radiation or no radiation so we only allowed each chap to do it for one day". He stated that the men involved in the task were fitted with full protective clothing, but that if they were upwind of the dust they were allowed to remove their respirators. He further said that the maximum dose received by any person in the course of the operation was 0.18 rads. 118. He also gave evidence of a further measure of radiation exposure that was applied to personnel working in this operation. This was a "thyroid count" which was used to reveal any measurable quantity of the isotope iodine 131 in the thyroid gland. This procedure involved the placing of an instrument which was extremely sensitive to beta radiation against the skin surface above the thyroid gland to determine whether any radiation was being emitted from the isotope in the thyroid, iodine 131 being readily detectable in the thyroid if there has been recent exposure of the body to it. He said that such a test was extremely relevant to the question of whether a person had swallowed or inhaled any radioactive material, as iodine 131, being a fission product, would have become almost immediately apparent in the thyroid if ingestion had taken place. He said "it would have gone straight there". 119. The test was fairly time consuming and, to his recollection, only the brush operators, being the personnel most likely to be exposed, were given the test. There were four such people and no measurable quantity of iodine 131 was detected. 120. It must be remembered, of course, that this test, like the readings from the dosimeter and film badge, did not record the presence of alpha emitters such as plutonium 239. They recorded predominantly gamma emissions with some beta. They were, however, an obvious indication of levels of radioactivity in the areas where the readings were taken. Such radioactivity found its origin in fissile materials, that is, direct products of the nuclear explosion. Alpha emitters had a somewhat different source to which I will refer. I should record at this point, however, that I accept the evidence of Major McDougall, given on more than one occasion in his oral testimony, that the amount of alpha emitters to be found in the vicinity of a ground zero after the detonation of a nuclear weapon and the hazard from them, was infinitesimal in comparison to the hazard from gamma and beta emitting fission products. 121. Major McDougall's view was that after fallout from a nuclear explosion had occurred there was a possibility of a plutonium 239 isotope, plutonium being used in the bomb, being resuspended in the air in the area of the fallout. However, in his view, it presented an infinitesimal degree of risk from the health physics point of view. Accordingly, although weapon debris would have been present during the Taranaki sweep-up operation, "the hazard from that debris at that point of time would have been assessed as small in relation to the hazard from fission products". He further said that alpha emitting plutonium 239 would have been present but, on the evidence of previous trials, would not have been present in quantities which could be assessed as presenting a hazard. He agreed that there was no measurement made of the presence of alpha activity during the sweeping operation. 122. On the question of the wearing of protective clothing during the operation, Major McDougall had this to say:- "The people who were involved in the sweeping operation were fully clad in protective clothing and wearing respirators and we put a health physics member of the team there to ensure that the people who were doing the brushing and were in the actual dust wore their respirators. If they were operating in Taranaki and were upwind, were not in the dust, then people were allowed to take their, I am pretty certain, to take their respirators off, certainly after the first morning, but carry them. When you say upwind; was there a noticeable wind influence?---No. No, there was very little wind on the days whilst the brushing operation was carrying on. Well, in those circumstances how can you define upwind?---Yes, I mean there was a wind but there wasn't a strong wind which you quite frequently saw at Maralinga which would actually raise the dust. There was a gentle breeze blowing. What, producing a perceptible drift in the dust haze as it were?---Correct. So, if you were upwind of that in the sense that you were not in the direction of the drift of the dust haze, you were allowed to remove your respirator?---I would've allowed people to remove their respirator." 123. Major McDougall went on the say that the operation was supervised by an extremely experienced scientist (now deceased). 124. The Major pointed out that the level of 0.3 rads had been selected on the basis that that was the normal level of permissible exposure for a worker in industry over a week. If a brush operator were to achieve that level of exposure he would not be employed again in the area for a week. This measurement was, in his view, "a very safe level" and would not exceed 15 counts per second if measured with a geiger-mueller tube. He said that a reading of above 15 counts per second was taken as "above tolerance", but that this inserted "an extremely large safety factor". He also expressed the view that most of the contamination detected on the clothing of those involved in the operation, resulted from "very large particles which would have been too big to go into a person's lungs and which would have been spat out. They would have been fission products resulting from the explosion". He also expressed the view that a person actually in the cloud of dust being stirred up by the sweeping operation would have been better off with the respirator on unless it became completely clogged up with dust, "because once you took it off you were breathing all this horrible muck, just sand and dirt". 125. In relation to the removal of respirators in risky conditions, a great deal of evidence was given by lay witnesses. This evidence related to areas of work other than the sweeping operation at Taranaki. I do not propose to deal with this evidence in detail. I gained the impression that the topic has, in general, assumed increasing prominence with the passage of time and in the course of discussion amongst the Maralinga sappers. 126. The most elaborate evidence in this regard was given by Mr Hutton the Lance Corporal who had been in charge of one of the working parties engaged in preparing the laneways and subsequently assisting in the removal of instruments after the explosions. Cubillo was not a member of Mr Hutton's party but, obviously, had contact with him from time to time whilst working on the range. It is difficult to evaluate Mr Hutton's evidence. He was a difficult witness. He was belligerent towards counsel and, on many occasions, apparently more intent on point-scoring rather than responding to counsel's questions in a temperate factual way. He gave the clear impression of being embittered in relation to his service at Maralinga and highly emotional in his recall of events. At the very least, I am driven to regard his evidence as exaggerated. I am not persuaded that respirators, when issued for obvious reasons of personal safety, were removed at the first available opportunity and with the connivance of responsible officers. In general, however, I am satisfied that when proper supervision was temporarily lacking, there may have been occasions when, because of heat and discomfort, respirators were removed. In other words, I am certainly not prepared to assume that all the evidence that has been given in this regard is the subject of fabrication, but I am certainly not prepared to accept that respirator removal was a regular feature of the working day in the forward area. 127. I return, then, to the question of Cubillo's activities during the Taranaki sweeping operation. I have referred to the difficulties involved in the acceptance at face value of his evidence in relation to the removal of his respirator whilst working in the dust. I found Major McDougall to be a most impressive witness. I am satisfied that the operation was organised with a proper regard to radiation safety in accordance with the health physics standards applicable at the time. The soldiers would have been instructed that respirators were to be worn except in the absence of dust. Specifically, they would have been instructed that respirators could be removed when they were upwind of the dusty area, but were to be replaced if dusty conditions occurred. 128. I am also satisfied that there was general supervision by appropriately trained health physics personnel present during the sweeping operation, although such personnel clearly could not be at the elbow of every person involved in the operation at all times. Obviously, a reasonable degree of reliance had to be placed upon the workers' obedience to instructions and their commonsense in relation to avoiding obvious danger. In the upshot, I am not persuaded that Cubillo removed his respirator in the manner and at the time that he asserts. The best that I would be prepared to find in his favour is that it is likely that he removed his respirator when he was upwind of the dust cloud stirred up by the operations. This he would have been permitted to do. It is certainly possible, however, that after removal of the respirator he wiped his face with a dusty glove and transferred dust to his lips. 129. I come, then, to the question whether the activities in which I have found that Cubillo was probably engaged, exposed him, on the balance of probabilities, to the risk of inhalation or ingestion of the isotope plutonium 239. This has been the subject of conflicting scientific testimony to which I now turn. SCIENTIFIC EVIDENCE ON EXPOSURE TO PLUTONIUM 239 130. The applicant called a health physicist, Mr F.P.J. Robotham, who provided two written reports which were tendered in evidence and who also gave extensive oral testimony. In his report of 5 May 1994, Mr Robotham refers to the Regulations and to Mr Turner's health physics reports in relation to the inter-trial period. In relation to permitted levels of exposure, he noted that "where the major concern was inhalation, ingestion or injection of radioactive isotopes, the maximum exposure was defined as being a level of surface contamination which did not exceed 10uC/m2". 131. He also stated that "during the inter-trials period potential inhalation hazards were monitored using cascade impactors. These had limited value because of the relatively small volumes sampled compared with the size of the area involved". 132. Mr Robotham placed considerable reliance upon the passage from Mr Turner's health physics report of March 1957 which has been cited above. He drew from it that "the decontrolled area immediately to the south of the marked yellow area was ... still active". The men, including presumably Cubillo, were therefore required to work in an active area without proper health physics protection. He spoke of the risks likely to have been incurred by Cubillo through working in this area in the following terms:- "My understanding is that between June and September 1957 Mr Cubillo was required to drill holes for fences. He recalls being issued with a film badge but not protective clothing. The sites were Tadje, Biak and Taranaki, before the tests at these respective sites. However, this general area had been contaminated by the Buffalo 4 (Kite) in October 1956. It is difficult to reconstruct a potential exposure for Mr Cubillo although there is a significant possibility of inhalation of radioactive material given the nature of his task and the locale." 133. He also stated that:- "Between April 1957 and October 1957 Mr Cubillo was required to drill holes at various sites in the forward areas. It is not possible to reconstruct Mr Cubillo's possible exposures from this activity. However, given the levels of residual contamination, especially from Breakaway, Mr Cubillo was at significant risk of inhaling or ingesting radioactive materials." 134. After he received further information from the applicant's solicitors in relation to the cooking of meals in these areas, this evidence, apparently, not having been referred to by Cubillo in the first instance, he added to his previous opinion in the following way:- "The statement of Mr Hutton, who was the Australian NCO, confirms the presence of Mr Cubillo during those mid-morning cooking sessions. Mr Cervetto confirms that no monitoring for radioactivity was carried out before these cooking sessions. What cannot be determined are the: . levels of radioactive contamination present; . types and solubility of radioactive materials present; . quantity ingested through cooking. Thus, it is not possible to quantify any radiation exposure Mr Cubillo may have received through eating food cooked in restricted areas. It is possible, however, to state that such practices should not have been allowed and the fact that the practice appears to have been widespread demonstrated lack of adequate supervision and training. (Mr Hutton described it as 'a recognized practice not only amongst the Australian Servicemen but also the British started to employ this method as well'.) In my earlier report I concluded that Mr Cubillo's involvement in drilling post-holes (star-pickets) could give rise to a 'possibly significant' internal hazard. The evidence from Mr Cubillo's workmates confirms this possibility and makes it more probable. Mr Cervetto's evidence shows that the drilling team also assisted in the erection of perimeter fences. The location of those fences is not clear, however, similar considerations apply to the digging of star-picket holes." 135. It must be noted, of course, that in forming and expressing these opinions, Mr Robotham has accepted the evidence that these activities occurred to a far greater extent than I have found to be the position. 136. As this part of the case forms a discrete segment, it is convenient to consider the evidence given in relation to it by Mr Davy, the health physicist called by the respondent. 137. In the first place, it is quite apparent that Mr Davy has had recourse to far more factual information in relation to the areas and levels of contamination experienced at Maralinga than has Mr Robotham. Through his research, Mr Davy not only challenges Mr Robotham's results but also the basis of his reasoning. In the first place, he establishes to my satisfaction, that it is more probable than not, that the areas in which Cubillo and the other men were required to work in the inter-trial period were not significantly contaminated, particularly by plutonium 239. He, in effect, negatives the concerns expressed in Mr Turner's health physics report of March 1957 and the associated letter from Mr Richardson. He points out that Mr Turner himself, in reports given later, resiled from the views that he had expressed in the earlier report. It will be remembered that the result of evidence which I have already considered was that the southern boundary of the "yellow control area" marked on the basic map of the inter-trial period was, in terms of the Regulations, in reality the southern boundary of the red area at the time when the work was going on. Consequently, the work was being done in an area where there was not even, in terms of the Regulations, a slight risk from inhalation or ingestion. 138. Mr Davy's evidence is fully supportive of this view. I found him to be a most credible witness and was very impressed with the extent of his experience in relation to the radiation hazards present at Maralinga, the depth of his research, and the reasoning processes by which he arrived at his conclusions. He paid close regard to evidence bearing on the question of the nature and extent of radiation hazards resulting from the Buffalo and Antler series and ensuing trials, particularly the Vixen series. He focussed particularly on the contamination of the relevant areas by plutonium 239. 139. It is, of course, important to bear in mind that this case is concerned only with Cubillo's inhalation or ingestion of plutonium 239. It is not concerned with Cubillo's exposure to gamma or beta rays resulting from the radioactive decay of other substances dispersed on the range as a result of the nuclear explosions, except insofar as measurements relating to the dispersal of those substances can throw light upon the quantity of plutonium 239 which might have been present at particular locations. Mr Davy's evidence makes very clear the nature and origin of plutonium 239 in the forward area. The explosion of a plutonium nuclear bomb results in fallout around the ground zero of the explosion. The radioactivity in that area is occasioned, in the early stages after the explosion, by the presence of radioactive elements with very short half-lives. These are subject to rapid radioactive decay which accounts for most of the ionising radiation emitted in the area. Plutonium 239 has a long half-life in excess of 24,000 years. Accordingly, present measurements of its existence on the range equate for practical purposes with measurements that would have existed at the time of the explosions. As Mr Davy points out there has been nothing worth mentioning by way of reduction in the quantity of plutonium 239 present on the range due to radioactive decay. 140. Moreover, the chemical composition of the bomb determines the amount of plutonium 239 which ultimately forms part of the radioactive field resulting from fallout from the explosion. Calculations based upon the amount of plutonium 239 produced by the ordinary processes taking place in the core of a nuclear reactor are of limited use in gauging the presence and effect of plutonium 239 after a nuclear explosion. It is clear from Mr Davy's evidence that very considerable scientific work has resulted in the production of what is named the "Baker Inventory Factor" which is used in determining the effects of plutonium 239 resulting from the explosion of plutonium nuclear bombs. Mr Davy explained these matters at some length in his evidence. There is no need to repeat the explanation here. It was uncontested and insofar as it plays a necessary part in Mr Davy's analysis of the situation at Maralinga, I accept it. 141. It will be observed that Mr Robotham's evidence as to the contamination of the areas in which the post-holes and other holes were being dug, was given only in very general terms. He advanced the view that those areas would have been contaminated by fallout from the Kite and Breakaway explosions in the Buffalo series. According to the health physics reports to which I have referred, these were the areas in which it was suggested that the engineers were required to work after the shifting northward of the yellow boundary in the inter-trial period. The nature of the contamination, if any, of these areas is therefore highly significant for the purposes of this case. This is a matter which Mr Davy examined in some detail. His examination is based upon available records which are lengthy and technical and which I shall not set out here. The results of his analysis may be broadly set out as follows. 142. The area in question is wedge shaped. It appears on the map in Schedule 1 to these reasons, the area having been copied from a map provided by Mr Davy as an attachment to his report (Exhibit 9). It is this area which contained fallout from the Breakaway detonation of 22 October 1956, the fallout having fallen to the south of the Pom Pom J7, J9 Nawa road line. The area would have been controlled as a red area by Mr Turner's health physics team if the yellow boundary line had not been moved north to a line along the Pom Pom-Nawa road line leaving the wedge shaped area decontrolled. There was not, however, a total absence of control. Movement north of Mina was limited wherever practicable, cascade impactors were run in areas where large bodies of men had to work, all meals were required to be eaten at Mina and there was an extensive removal of the top soil at the Tadje site. The construction of the Tadje tower and site occurred in this area as did the preparation of the Biak site. 143. In Mr Davy's considered opinion, the Taranaki site was never contaminated with fallout from any detonation of the Buffalo series. Consequently, the question whether Cubillo could have suffered harm from inhalation or ingestion of plutonium 239 is restricted to work he may have done in the Tadje or Biak areas. The renovation of the Gona tower also took place within the wedge but there is no suggestion that Cubillo performed any work there. 144. The Breakaway fallout in the wedge area was unique in the Maralinga experience. According to Mr Turner's July 1957 report, it consisted of "millimetre sized beads of a glass appearance" . Both Mr Robotham and Mr Davy agreed with Mr Turner's evaluation that these beads did not constitute an inhalation or ingestion hazard. They "came from the stem of the cloud rather than from the mushroom of the cloud". They constituted very early fallout from the Breakaway explosion. It is accepted that the beads themselves were radioactive. As I understand the evidence, they emitted gamma rays. Mr Davy's opinion, which I accept, was that the bead which Cubillo found on portion of the dismantled tower in the yellow area was in fact a bead from the Breakaway fallout. It emitted gamma rays as was obvious from the geiger counter reading to which Cubillo referred in his evidence. However, because of their size and weight the beads could not have become resuspended in the air as a result of the work being carried out in the area. For this reason they could not have been ingested or inhaled, even if that were possible having regard to their size. 145. It was put to Mr Davy in cross-examination that the presence of the beads in this area would be indicative of the presence of other radioactive materials, including alpha emitters, which would be capable of being resuspended and, therefore, being either inhaled or ingested by men working in the area. Mr Davy did not agree with this suggestion. His view was that the presence of the beads was by no means an indicator of the presence of other fallout in the nature of "fine particulate". Such material would originate in the mushroom of the cloud and be subject to later fallout. It was not valid to assume that "fine particulate" would also be present in the area where the beads were found. I do not understand any evidence of Mr Robotham to be to the contrary. I accept Mr Davy's evidence. 146. Moreover, the Tadje site, insofar as it may have represented a radiation hazard from the Breakaway or Kite detonations, was decontaminated by the removal of the top soil before Cubillo commenced work at Maralinga. The Biak site was not within the wedge of the Breakaway fallout. Nor was it subject to any contamination from the Kite detonation. The evidence of Mr Davy based upon the March 1957 health physics report is uncontested and, in my view, clearly indicates that this was so. 147. I am quite satisfied, on the balance of probabilities, that Cubillo, whilst working and eating in the "laneways" areas in the inter-trial period, was not subject to any inhalation or ingestion hazards resulting from fallout in those areas from any of the detonations in the Buffalo series. 148. In reaching this conclusion I have not failed to take into account suggestions in the evidence as to the hazardous effects of dust storms and some references to the breaking up of glazed areas in the vicinity of the ground zeros and the disturbance of the broken up surfaces by wind. The suggestion was that the effect of wind disturbance was the movement of radioactive materials into the areas where the men were working. These suggestions are only in the most general form. They are not backed up by measurement records or by any form of considered calculation. I am satisfied by Mr Davy's evidence that any such movements would mainly occur at ground level and over small areas. Also, it is to be presumed that work would not be carried out in conditions of true dust storms. Moreover, there is no meteorological evidence tendered on behalf of the applicant to suggest that such storms occurred to any significant degree or, indeed, that severe wind conditions were experienced with any frequency. Mr Davy's evidence, based upon a perusal of meteorological records, is to the contrary. 149. Mr Davy also referred to inferences that may properly be drawn in relation to work in this wedge shaped area from film badge readings for the period May 1957 to the commencement of the Antler series in the September. In that period Cubillo received a total gamma ray exposure of 0.15 rem and his commanding officer, Captain Marqueur, accumulated a dose of 0.17 rem over a somewhat longer period. Mr Davy makes the point that both these doses are smaller than 0.23 rem which is the anticipated annual dose that an individual receives from natural background radiation. 150. Mr Davy also makes the point, on what appear to be quite valid grounds, that in November 1958 Mr Turner, in the course of a review of his findings, came to the conclusion that his earlier concerns about men working in the decontrolled wedge shaped area were unfounded. In other words he came to the view that, in retrospect, he had erred by referring to the area south of the newly established yellow boundary as being potentially a red area. Mr Davy explains this matter in his evidence. The explanation is not contested by any evidence to the contrary. I am quite satisfied to accept it. 151. The result is that the applicant fails to satisfy me that he was subjected to any risk of inhaling or ingesting plutonium 239 whilst working in these areas in the inter-trial period. 152. I come, then, to consider whether the applicant has established any scientific basis for an assertion that he was at risk of inhalation or ingestion of plutonium 239 when he participated in the retrieval of the dismantled tower parts. It is sufficiently clear that this must have taken place in the yellow controlled area and was therefore subject to health physics supervision. There is the evidence, which I accept, of the brushing aside of the radioactive fallout bead. There is also a suggestion in the evidence that walking about in the area produced dust. The difficulty is that Cubillo's evidence is so vague that it is simply not possible to conclude, even on the balance of possibilities, that he inhaled or ingested any dust. In fact he does not assert that he did. Even if one assumes in his favour that he was not wearing a respirator and that by wiping his face he transferred dust to his lips or nose, there is a total absence of evidence as to the amount of dust that he might have taken into his body in this way or of any computation of radioactive dose that he might thereby have acquired. 153. It is convenient, in this context, to consider an argument which was put forward on behalf of the applicant on the basis of a portion of the evidence given by Mr Robotham and also Dr Kefford, to whom I shall refer in greater detail later. Both these witnesses, Mr Robotham faintly and Dr Kefford quite explicitly, espoused the view that irrespective of measurements of dose, a person in the position of Cubillo could fall victim to a radiation hazard by inhaling or ingesting "a small particle" of plutonium 239. Mr Robotham's evidence was, in fact, given in relation to a speck of polonium 210 of a microcurie in radioactivity. Dr Kefford's evidence was less specific but certainly involved the concept of the inhalation or ingestion of an airborne particle of pure plutonium 239. I am satisfied that the question whether this could happen lies within the realm of health physics rather than medicine. 154. Professor Doll, who gave evidence mainly in the field of epidemiology, an area to which I will refer later, was fully qualified by learning and experience to speak on the medical aspects of radiation and cancer. He was not prepared to give any opinion as to the possibility of such an inhalation or ingestion. He regarded it as being in the field of health physics. Other medical experts in the case gave evidence to the same effect. I am satisfied that the opinion expressed by Dr Kefford lay outside the field of his expertise and, accordingly, I give his view little weight. 155. It was, however, well within Mr Davy's field. He was quite positive that the inhalation or ingestion of such a pure speck or particle of plutonium 239 was not something that could occur in nature. At most such inhalation or ingestion would be of particles of dust or dirt to which some atoms of plutonium 239 could adhere. Accordingly, the question was always one of estimation of dose measured in rems. Unless the amount of material received into the body carried with it a radiation dose at a level accepted as hazardous, then the exposure could not be regarded as a harmful one. I accept Mr Davy's evidence in this regard. Indeed, I prefer his evidence to that of Mr Robotham wherever there is a conflict between the two. 156. I am unable, upon the scientific evidence, to find that Cubillo was exposed to a hazardous level of plutonium 239 whilst involved in the retrieval of the tower components. 157. I come, then, to the Taranaki sweeping operation. Did the removal by Cubillo of his respirator and the wiping of his face, in the circumstances that I have found, carry with it, on the scientific evidence, a risk of inhalation or ingestion of plutonium 239? 158. Both Mr Robotham and Dr Kefford expressed the view that Cubillo was exposed to such a risk. Dr Kefford's view was founded, primarily, on the facts that the area was contaminated by fallout from the Biak detonation, that Cubillo was exposed to dust and dirt from the surface of the ground where the fallout had occurred, that his clothing was clearly contaminated and that he had introduced the dust and dirt to his mouth and nose by wiping perspiration from his face. These facts, coupled with Dr Kefford's espousal of the "particle" theory, led him to infer that Cubillo had received plutonium 239 into his body. Mr Robotham was also impressed by these facts. In addition to them, he undertook some calculations which led him to assert that Cubillo was significantly at risk from exposure to plutonium 239 during this operation. These calculations were hypothetical in nature, not being based upon any actual measurements made at the time or in relation to the fallout from the Biak detonation upon the Taranaki site. 159. Mr Davy, on the other hand, made calculations which were based upon available measurements. He did not criticise Mr Robotham's methodology, but expressed the view that his results were flawed because he had proceeded upon erroneous assumptions. Relying on these assumptions Mr Robotham had arrived at an estimate of Cubillo's exposure to alpha emitters in the course of the sweeping-up operation of 1,000 millisieverts, this exposure being due to inhalation or ingestion of plutonium 239 and being significantly high. It was based upon an estimate that 10% of the radioactivity present in dust resuspended into the air during the clean-up was due to the presence of the plutonium 239. This was purely an estimate and was heavily challenged by Mr Davy. 160. Mr Davy, in fact, went to considerable lengths to arrive at a view of the extent of plutonium 239 present in the fallout from the Biak detonation. In doing so he quite clearly paid careful regard to records relating to surveys of radiation in the area which were not considered at all by Mr Robotham. Mr Davy was able to make useful comments based upon his involvement in the clean-up operations at the Maralinga site. 161. As has been mentioned, the long half-life of plutonium 239 means that measurements of its presence in the area of Biak and Taranaki made many years after the Biak explosion would not and do not differ from measurements made shortly after it. In theory, therefore, measurement by any acceptable means of the level of plutonium 239 in the area would give a clear indication of the extent to which it was present after the test in 1957. However, the situation has been complicated by the fact that the Vixen B trials, which were conducted some time after the Antler trials, further contaminated the Taranaki area with plutonium 239. These trials, however, did not contaminate the whole of the area previously contaminated by the Biak detonation. Consequently, part of the area between the Biak ground zero and the Taranaki site still contains only the plutonium 239 that was deposited by the Biak detonation. This fact has enabled significant calculations to be made. I accept, from Mr Davy's evidence, that it is possible to accurately measure, by established scientific means, the amount of plutonium 239 remaining in the relevant area. 162. The distance from the Biak ground zero to the Taranaki site is 2.7 kilometres. An aerial survey conducted in 1990 as an adjunct to reporting on the rehabilitation of the former nuclear test sites determined that "deposited plutonium 239 could not be delineated by the aerial survey more than 1km from ground zero for Biak. The limit of detection at this point equates to about 60kBq/m2 (1.6uCi/m2) and the level of deposited pu/239 would be expecte d to drop off further in the 2.7km separating Biak from Taranaki". 163. Mr Davy was asked what he could say about the concentration of plutonium 239 which could be expected as distance from the Biak ground zero increased. He gave the following answers:- "... the plutonium is formed mainly by nuclear reactions within the case of the weapon. It is an integral part, its formation is an integral part of the nuclear detonation, and therefore it will be distributed in a constant ratio to all the other fission products, and as - just from the point of view of spreading out, you get a reduction in the density of fission products as you move further and further away from the point of detonation, so too will you get a reduction in the amount of plutonium 239 on the ground as you move further and further away from the point of detonation. So, in this case we know that 1 kilometre from the ground zero from Biak, the activity is 1.6 microcuries per square metre, is that right?---Correct. We know that, in fact, there is 2.7 kilometres from Biak to Taranaki?---Correct. What does that say about the level of activity which one would expect at Taranaki in relation to the 1.6 microcuries per square meter 1 kilometre from ground zero at Biak?---You know for certain it will be less." 164. Mr Davy went on to say that it would not be proportionately less, there being no simple relationship with distance. In fact, the amount of dispersed plutonium 239 dropped off far more quickly than would be expected from "just straight distance". 165. Mr Davy indicated that, although the Biak site had been cleaned up in 1964, the area where the reading had been taken had not been touched in that clean-up. As a result the reading obtained was a clear indication of the level of plutonium 239 present at the time of the Taranaki sweep-up. He also indicated that the Taranaki detonation would not have had any effect upon the area where the reading was taken. Nor was it affected by the subsequent Vixen B firings. Consequently, the reading of 1.6 microcuries per square metre 1 kilometre from the Biak ground zero, provided "an upper bound" for calculations of the level of plutonium 239 deposited at Taranaki by the Biak explosion. 166. Mr Davy also said, in relation to the dispersion of plutonium 239: "...the formation of the majority of the plutonium 239 is by a nuclear reaction which is part of the nuclear detonation within the case of the weapon, and over and above that there's a small part that is unconsumed plutonium from the weapon itself, but it is explosively dispersed in the same way as all the mixed fission products, and it is not physically possible to have plutonium by itself. It would always have to be along with other fission products that were formed at the same time." 167. As a result of this, Mr Davy was able to indicate that there would be a similar proportion of plutonium 239 to be found amongst the general fission products (some 150 in number) at the Taranaki site after the Biak explosion. He also stated, and I accept, that the result of research made it "technically feasible and quite proper to relate the quantity of plutonium 239 on the ground from the known amount of mixed fission products on the ground". He also said that "for any detonation there is a very specific relationship between the amount of plutonium and the amount of mixed fission products and it is a relatively small number - and if you do not detect mixed fission products with an efficient detector then you can be very confident that there is no likelihood of inhalation or ingestion of plutonium". 168. This was a very significant consideration, having regard to the testing done by the health physics personnel to detect the presence of iodine 131 in the thyroid glands of men involved in the Taranaki sweep-up. As indicated earlier, iodine 131 is a fission product which rapidly finds its way into the thyroid if it has been inhaled or ingested. From the records, Mr Davy inferred, reasonably in my view, that the four persons tested in this way were the drivers of the vehicles. This was on the basis that the drivers would have been the persons most exposed to radiation during the operation. There was no iodine 131 detected in their thyroid glands. This clearly indicated that they had not inhaled or ingested plutonium 239 either. As it is reasonable to infer that Cubillo would have been less exposed than a driver then, a fortiori, there is no indication that Cubillo was exposed to any risk of inhalation or ingestion of plutonium 239 during the sweep-up operation. Mr Davy's evidence was very firm that the absence of iodine 131 is a clear indication that none of the potential airborne radionuclides resulting from the detonation have entered the physiological system of the person tested. I accept this view. 169. Mr Davy also approached the question of Cubillo's exposure using similar methodology to that adopted by Mr Robotham. In the process, he exposed, accurately in my view, the errors that had entered Mr Robotham's analysis by reason of his flawed assumptions. I do not propose to set out this part of Mr Davy's evidence. Rather, I will record Mr Davy's own analysis and the conclusions of his analysis in relation to exposure, with accompanying comments on Mr Robotham's evidence where appropriate. 170. Mr Davy commenced his analysis by selecting an appropriate dosimeter reading for the Taranaki sweep-up. Whereas Mr Robotham had accepted Mr Cubillo's alleged reading of 0.3 rem, Mr Davy had recourse to the actual dosimeter reading recorded for Mr Cubillo. He also had regard to Cubillo's film badge reading for that day. The relevant dosimeter reading for Cubillo was 0.1 rem whilst the gamma dose recorded by his film badge was 0.07 rem. The highest dose for the day recorded by any person involved in the clean-up was 0.18 rem. Mr Davy applied in this calculation as in all other calculations made in relation to the case, a philosophy which he described as that of selecting "the upper bound". Accordingly, he accepted for the purpose of his calculations the figure of 0.18 rem as an indication of the gamma dose recorded by a dosimeter worn at waist level. He had regard to Mr Cubillo's height and accepted that the dosimeter would be recording at a level of approximately one metre above ground. 171. This figure provided him with the basis to make a calculation of the density of gamma surface contamination which would be required to produce such a dosage reading at such a level above ground. Mr Robotham had selected a conversion factor based upon tables which, in Mr Davy's opinion, was more appropriate to "a reactor core at equilibrium burn-up" than "for a weapon where you have the complete range of short lived and long lived fission products". Mr Davy selected a conversion factor appropriate to the explosion of a nuclear weapon and a resulting radiation field 48 hours after explosion. I am prepared to accept that Mr Davy's approach was the correct one. It has the effect of reducing Mr Robotham's figure by a factor of three. 172. These adjustments to Mr Robotham's approach led Mr Davy to conclude that Mr Robotham had overestimated the degree of surface contamination by a factor of about 14 "with the same reduction applying to his estimate of airborne concentration resulting from resuspension of the surface contamination". Mr Robotham's calculation had produced "a gamma surface contamination level of about 10 -2Ci/m2". 173. It was then necessary to apply "a resuspension factor" in order "to relate the activity on the surface of the ground to that which can become airborne and breathed in". Resuspension factors are arrived at empirically. There was, in fact, no direct measurement made of any such factor during the Taranaki sweep-up operation. However, by having regard to factors established in similar situations in the Buffalo series, it was possible to make a reasoned guess at an appropriate factor to be applied in the Taranaki situation. Mr Davy also had regard to what Major McDougall had noted as to features of the dust stirred up in the Taranaki operation. 174. It was also necessary for Mr Davy to consider the nature of the activity which could become suspended. In particular, it was necessary to arrive at a judgment as to the relevant quantities of plutonium 239. Mr Robotham had simply hypothesised that plutonium 239 would constitute 10% of the airborne material. 175. Mr Davy, on the other hand, had regard to the measurements available as to the presence of plutonium 239 at the one kilometre distance from the Biak site which "had to be less than 1.6 microcuries per square metre of plutonium 239". According to Mr Davy's expert opinion this figure had to be further decreased by "a factor of 10 down to take into account research published in America relating to plutonium 239 used in particular types of weapon. This reduced the relevant figures to something between 0.1 and 0.2 microcuries of plutonium 239 per square metre". On the "upper bound" philosophy Mr Davy selected the higher figure. This in turn required a very substantial reduction in the dose figure for plutonium 239 which Mr Robotham had arrived at on his calculations. The appropriate reduction was 1/625. The result was that the estimated dose received by Cubillo during the Taranaki clean-up due to the presence of plutonium 239 in the suspended material was necessarily reduced from Mr Robotham's figure of 1,000 millisieverts to 1.6 millisieverts. The further correction factor of 10 was then applied to this figure resulting in a dose estimate of 0.16 millisieverts which Mr Davy, on the "upper bound" philosophy, was prepared to increase to 0.2 millisieverts. 176. I accept Mr Davy's computation as indicating the upper limit of dose likely to have been received by Cubillo by way of inhalation of plutonium 239 during the work at Taranaki. It may be noted that this calculation assumes the absence of a respirator. 177. There remains the question of whether Cubillo could have ingested any plutonium 239 by transferring dirt and dust into his mouth when he wiped his face in the manner previously described. Mr Robotham only deals with the alleged risks of this activity in general terms. Mr Davy approaches it differently. The matter was directly raised with Mr Davy in cross-examination in the following passage:- "...why would it not be possible for Mr Cubillo to ingest an atom of plutonium 239 when wiping his face, brow, with his glove to remove perspiration?---I would think that the transfer of surface contamination from the glove to become surface contamination on the lips, albeit a very reduced level, is a feasible - a feasible process and I would accept that you could, by licking your lips, ingest some of that dust. Is that what you are asking me? And in relation to that, if ingested, we do not know at this stage the dose that was ingested if it occurred?---I can't agree with that statement. Why do you not agree with that statement?---I would say that the knowledge of the weapon, the knowledge of the process of deposition of fission products, the knowledge of the formation of higher isotopes of uranium and their subsequent decay into plutonium, predetermines the existence of a series of ratios which can then be used to quantify, albeit, in an upper bound way, the dose that could result from the hypothesis that you have just put. And I would add the point that as I put in evidence that the transfer of a plutonium compound, a plutonium oxide compound, across the gut wall, is extremely small, 0.001 per cent and 99.999 per cent of that plutonium that you envisaged being on some of the dust on the lip would be passed straight out." 178. I shall return to the proposition in the last sentence later in these reasons. Mr Davy was pressed with the possibility that some significant amount of plutonium 239 could be ingested in this way. He did not accept the suggestion. It was put to him that his calculations did not "deal with the situation ... of just, say, one occasion when he is wiping his glove, his contaminated glove, across his face and lips". It was put that, in such circumstances, "we do not know how many atoms he would have ingested or could have ingested". Mr Davy's answer was:- "One way of doing that, and it's a standard Health Physics approach, and you could have asked Mr Robotham to do it, is to estimate the area of the lips, not a very hard parameter to estimate, you can estimate the layer of dust on the lips that leads you to the belief that your lips need licking and that's not a terribly difficult parameter to provide your estimate for, and you can work through the arithmetic and you'll end up by concluding that this scenario no matter how spectacular it may sound is not significant compared with the total dust loading that arises with a resuspension factor of 10 to the minus 4 ... The glove scenario is not a significant scenario, I'm sorry." 179. Later, Mr Davy had this to say in relation to this topic:- "Perhaps if I could make my point a little clearer. If you assume that he wore no respirator at any time then I have stated that if you look at experiments on resuspension factors then the amount of dust you would inhale and ingest by working in an area where you have got a resuspension factor of 10 to the minus 4 would swamp that scenario of transferring it from the glove. Now, if you wore your respirator at all times when you're exposed to contaminated dust and the only time you took your respirator off was when you're in a relatively uncontaminated area that was upwind of the sweeping operations so that you can't inhale dust, then of course the scenario of getting something off your glove is obviously greater than inhaling nothing, but it is not significant in terms of total activity. HIS HONOUR: When you say total activity you mean the amount of radioactive material that may have been ingested?---To lead to a significant risk, yes. To lead to any risk from that amount of material?---Yes." 180. I found Mr Davy's evidence on this matter quite compelling. Contrary to the evidence of Mr Robotham and Dr Kefford in relation to the possibility of ingestion in these circumstances, I am not prepared to attribute any significance to the fact that Cubillo may have wiped his face with a contaminated hand or glove. I accept Mr Davy's evidence as to the "upper bounds" which can be applied to the inhalation and ingestion of plutonium 239 by Cubillo at Taranaki. The question remains, of course, whether the amount that might have been inhaled or ingested, extremely small as it was, could, nevertheless, have some bearing upon Cubillo's later development of renal cell cancer. This matter has been dealt with in the evidence as a question of health physics, oncology, and epidemiology. I shall now consider the health physics evidence. EFFECT UPON KIDNEY OF INHALATION/INGESTION OF PLUTONIUM 239 - HEAL TH PHYSICS EVALUATION 181. This topic can be dealt with fairly briefly as, in the upshot, there is no conflict between the evidence of Mr Davy and Mr Robotham. The evidence of both is based upon research material, the validity of which is fully accepted in the scientific community. This material comprised certain tables and an associated tape devised by the International Commission on Radiological Protection (ICRP). The tables, which were produced in an eight volume set in 1970 and described as "ICRP 30 - Limits for Intakes of Radionuclides by Workers", incorporated all data which had been established since 1955 when the concept of the existence of critical bodily organs for specific radionuclides had been introduced into health physics. The critical organ is that organ which receives the highest dose of an ingested or inhaled radionuclide as a result of the concentration of the radionuclide in that organ, the mode of decay of the radionuclide and the size of the organ. For instance, bone is the critical organ for "bone seekers" such as radioactive calcium, radium, strontium, uranium and plutonium 239. 182. In ICRP 30 the main addition was the incorporation of a factor to account for the radiosensitivity of the various organs. This refinement was possible as a result of the continuing studies on Japanese persons who had survived the atomic bombs. The tables were very extensive. However, apparently because of considerations of size, not all material was published in this form. ICRP also kept in the form of recordings on tape a great deal of information in relation to radionuclides and target organs which was seen to have only limited application. The material kept on tape was, however, readily accessible to anyone interested. 183. Mr Davy gave evidence in relation to this material. He stated that in relation to plutonium 239 the ICRP tables simply do not mention the kidney as a potential target organ. To obtain any information in this regard it is necessary to have recourse to the tapes. Mr Davy then considered the information in the tapes in relation to his calculated dose of 0.2 millisieverts of plutonium 239 received by Cubillo at Taranaki. According to his unchallenged calculation from the tapes, the dose to the kidney through ingestion of this quantity of plutonium 239 would be 10-12 rem which is, as he said, "a very very small number". He stated that "virtually none of any ingested or inhaled plutonium ends up in the kidney. It is not possible to irradiate the kidney by ingesting or inhaling even reasonable quantities of plutonium". 184. The figure for inhalation of plutonium 239 was similarly small. By way of illustration Mr Davy compared these doses to what might occur in every day circumstances. He said "in terms of spending a period of time in an ordinary residence it is less than a second. The actual radon given off by those brick walls in your house, you are there for less than a second and you have exceeded by a fair degree the doses we have just been talking about". 185. Mr Davy further pointed out, in a passage already quoted, that 99.999% of ingested plutonium 239 would not pass through the gut wall into the human bloodstream, but would simply be harmlessly excreted. Furthermore, in relation to plutonium 239 passing from the blood to the kidney, there was an extra discrimination factor of 100, "so in terms of not going to the kidney 99.99999 is what we are up to". 186. In addition to this evidence, Mr Davy supplied a highly complicated and sophisticated calculation, which was totally unchallenged, and which took into account the Baker Inventory Factor referred to earlier. It also took into account factors used in the calculation previously referred to in relation to Cubillo's exposure to plutonium 239 at Taranaki. The result of the calculation was a dose to the kidney of 0.002 rem. This was 35 times less than the radiation dose which the kidney would receive in a year from natural background radiation. 187. Mr Robotham did not deal with this question in his evidence-in-chief. However, he was cross-examined in relation to it. He agreed that ICRP did not consider the kidney as a target organ for plutonium 239. He had heard of the ICRP 30 tapes but had not used them. On being shown the relevant portions of the tapes he agreed that of 100,000,001 units of plutonium 239 inhaled 100,000,000 would go to the lung and only 1 to the kidney and that the position was similar in relation to ingestion. The following exchange then occurred:- "Is it then the situation, Mr Robotham, that we really can discount the relevance of all the relevance we heard about plutonium 239 and Mr Cubillo in this case, given Mr Cubillo's renal cell carcinoma?---Yes, I would say that the ingestion or inhalation of plutonium under such circumstances would contribute only a small dose to Mr Cubillo's kidney. Small? We are talking about differences of between 8 million and 10 million?---Yes. When you are talking about those differences, is that what you mean by a small difference?---It's extremely small. It is infinitesimal, is it not?---I'll grant that, yes." 188. He was then cross-examined as to the various activities engaged in by Cubillo at Maralinga, and as to whether they could now be relied upon as occasions when he could have suffered radiation harm to his kidney. He agreed, in effect, that where plutonium 239 could be the only active agent, as opposed to polonium, the activity could be removed from consideration. He agreed that the cleaning of the Taranaki site was "gone". Similarly, the dismantling of the camera tower. The drilling of the post-holes and the other holes had no relevance, assuming, as was the case, that Cubillo could not have been exposed to polonium during those activities. Also, the eating of food cooked on shovels was irrelevant. In the upshot, Mr Robotham agreed that plutonium 239 could be excluded as having any causative effect whatsoever upon Cubillo's renal cell cancer. Only the possible inhalation or ingestion of polonium 210 remained relevant as a cause. 189. In the circumstances that polonium 210 as a potential cause of Mr Cubillo's damage was abandoned, it would appear that at the end of Mr Robotham's evidence the applicant had no case. However, Cubillo gained some support from the evidence of Dr Kefford, the only medical witness called on his behalf. I turn, therefore, to the medical evidence. THE MEDICAL EVIDENCE 190. Dr Kefford, an oncologist, supported the thesis that the ingestion of plutonium 239 could have caused Mr Cubillo's subsequent renal cell cancer. He based this theory on the likelihood of Cubillo having swallowed a particle of plutonium 239 whilst working in the dusty contaminated conditions of the Taranaki sweep-up. He said that the ingestion of a very small particle of plutonium 239 would be sufficient to cause carcinogenic changes in the kidney of persons of a particular genetic make-up. Radiation would cause mutation of tissue and adversely effect tumour suppressor genes which operate to prevent the formation of tumours by cell division. 191. It is not entirely clear whether Dr Kefford is postulating a particle of pure plutonium 239 as he also speaks in his evidence of the deleterious effect of specks of radioactive dust. Insofar as his views are reliant upon a concept of the ingestion of a particle of pure plutonium 239 I reject them. I am, indeed, satisfied that the existence or otherwise of such particles resulting from fallout from a nuclear explosion is a matter in the field of health physics. In this regard, I have been amply satisfied by the evidence of Dr Davy that such particles do not in fact occur other than in controlled conditions. 192. However, I have come to the conclusion that Dr Kefford's evidence in this regard amounts really to an assertion that extremely small amounts of the isotope, such as might adhere to the surface of a speck of dust, would be sufficient, if inhaled or ingested, to induce carcinogenic effects in the human kidney. So seen, his evidence espouses a thesis that very low doses of radiation can cause renal cell cancer and that such a low dose can be administered by the introduction into the area of the kidney of a small quantity of an alpha emitter which, in this case, can only be plutonium 239. 193. Considerable criticism has been levelled at Dr Kefford's evidence by counsel for the Commonwealth. I was not impressed with him as a witness. He tended to be abrasive, partisan, and dogmatic. He not infrequently appeared to assume the role of an advocate rather than of an impartial expert. I am not prepared to find, however, that he was totally lacking in credibility because of these blemishes on his testimony. His expertise in oncology requires that his opinions be carefully considered in conjunction with the rest of the expert medical testimony in the case. Moreover, because of the final state of Mr Robotham's evidence, it is Dr Kefford's testimony that is the linchpin of the applicant's case on causation. 194. Dr Kefford furnished reports and gave oral testimony. His first report is dated 25 November 1994. His second report is dated 6 March 1995. The first report followed upon an examination of Cubillo. The second contains comment apparently based upon statements of the applicant's lay witnesses and copies of the respondent's "epidemiological evidence" provided to Dr Kefford. I set out two passages from the first report:- "Between 1957 and 1958 he worked as a Field Engineer in the Royal Australian Engineer Corp of the Australian Army at the Maralinga Test Site for British Atomic Weapons. At this time he was aged 28-29. His precise movements, duties and radiation exposure during this time has been well documented by others and I shall not enlarge upon it here, except to say that he was clearly exposed to significant alpha emission, by inhalation, slight to possibly significant beta exposure by inhalation, and moderate gamma emission by external exposure. It would appear that the most hazardous task in which he was involved was working in the Kittens areas (Naya) where large quantities of Polonium 210 had been dispersed. It is also clear that his protection was minimal to non existent at time despite adequate information at the time about the harmful effects of exposure to ionising radiation, and that had effective control procedures been implemented his exposure to radiation hazards during this time would probably have been minimal. His internal exposure may have been as high as 20Sv or more, depending on the quantity of Po 210 inhaled." (In his oral testimony Dr Kefford observed that the figure 20 was a typographical error and should have been 2.0. Also Po 210 (polonium 210) should have read Pu 239 (plutonium 239).) "The cause of Grawitz tumour (renal cell carcinoma) of the kidney is unknown. Smoking is a definite risk factor and about 30% of renal cell carcinomas are caused by smoking. Heavy radiation exposure of the type experienced by Mr Cubillo is associated with the causation of this cancer as it is with most human cancers, and the time lag of between 18 and 24 years between exposure and induction, is consistent with a causative link based on data from the Hiroshima bomb survivors. The high incidence of renal cell carcinoma in patients examined with thorotrast in the 1920's is attributed to its emission of alpha and gamma radiation. To my knowledge alcohol abuse is not a known risk factor for Grawitz tumours. I would regard the occurrence of a Grawitz tumour in this man during his late forties as being probably linked to his previously heavy radiation exposure during the Maralinga tests". 195. The relevant portions of the second report read as follows:- "I am appalled to read of some of the working conditions, particularly the fact that the men working on camera towers very close to the blast site used for the 1956 blasts had to remove their respirators because of extreme heat. On Page 2 of Robert Chasty's statement: 'we all removed our respirators, even the English chap. We would wipe our faces with the back of our gloves to wipe the perspiration off our brow and also to clean the glass of the respirator so we could see we then put our respirators back on again'. He states that they were not monitored by health physics people during this time. In relation to the BICC mast he also states 'the problems of accidentally breathing or eating radioactive material were never explained to me nor were the precautions to be adopted to prevent the problems. There were times when we ate food and cooked it near or on test sites particularly when we were doing the star-pickets. It would have been in 1957 or so that we started to cook food on shovels out near where we were working. I am sure we were working in the forward areas at the time'. It is clear that the great masses of epidemiological evidence provided by overseas experts is irrelevant to this situation. It is quite clear that the inhalation and ingestion of radioactive material could have been extremely high, and therefore I am even more convinced of my original statement that there is a high probability that Mr Cubillo's renal cell carcinoma was caused by exposure to radioactive material inhaled or ingested as a result of his activities at Maralinga." (Work in relation to the BICC mast was specifically excluded from the applicant's case as carrying no relevant radiation hazard.) 196. It may be noted that Dr Kefford appears to have emphasised in these reports the importance of the "heavy" nature of the alleged radiation exposure. In this regard it is apparent from the reports and also his later evidence that he had accepted as fact the level of internal dose of 2.0Sv, which had been arrived at as a purely hypothetical figure by Mr Robotham. He also emphasises the high risk factor involved in Cubillo's heavy smoking. He accepts as "quite clear that the inhalation and ingestion of radioactive material could have been extremely high". Finally, he dismisses "the great masses of epidemiological evidence" as being clearly irrelevant. 197. Surprisingly, in view of the wording of these reports, in his oral evidence Dr Kefford eschewed any reliance, in the forming of his opinion, upon a "heavy" dosage of radiation. Indeed, he said that he regretted using the word. He made it clear that he had no expertise in the field of radiation or health physics and was totally reliant upon the material provided by Mr Robotham in this regard. Furthermore, on a number of occasions he expressed the opinion that the level of dosage received by Cubillo was not particularly relevant insofar as the inhalation or ingestion of a small particle or speck of alpha (and perhaps beta) emitting radioactive material would be sufficiently carcinogenic when in proximity to Cubillo's kidneys to produce his renal cell carcinoma. 198. He was not concerned with the problems arising from the information on the ICRP tapes which had led Mr Robotham to exclude plutonium 239 from any significance in the case. He agreed that those figures would indicate that in the case of an inhalation of 100,000,000 plus one units of plutonium 239 100,000,000 "would go to the lung and one only would go to the kidney". He disagreed, however, that "in terms of inhalation the kidney is not a target organ". It was sufficient "that radiation producing substances are reaching the kidney in minuscule amounts". This was because there is "no simple dose relationship between radiation dose and carcinogenesis". 199. He expressed the opinion that the ICRP information applied only to "distribution of dose to different organs, but said nothing as to carcinogenesis". This would depend upon the "individual specific tissue sensitivity to radiation". Accordingly, if an individual had a particular sensitivity to radiation induced cancer of the kidney, the "minuscule" amount of plutonium 239 which could reach it would, nevertheless, be sufficient to initiate carcinogenesis. Dr Kefford further explained his approach by reference to molecular biology. He gave evidence as to the mechanism by which the radioactive particle acted as a cancer producing agent. He said: "precisely what happens ... is that individuals with a particular genetic make-up who are predisposed in certain tissues to the effects of radiation undergo mutations, actual physical base changes in the DNA of the cell of the tissue that is being irradiated and that those mutations when they occur in genes that regulate the cell cycle, release the cell from a negative effect on cell growth, such that it goes into continuous cellular-like division. ... these genes are called tumour suppressor genes and they have only been recently discovered." 200. In a later passage Dr Kefford also spoke of radiation damage that could be caused to other genes "which affect DNA repair". He said "all our cells have a molecular machinery to protect us from DNA damage and if that machinery itself is damaged by physical or radiating carcinogens then the cell is particularly predisposed to another carcinogenic event". 201. In relation to the acknowledged deleterious effect of Cubillo's previous smoking habit, Dr Kefford introduced the theory of synergism. He gave the following evidence on this topic:- MR PUCKERIDGE: If you could indicate what that is?--- Synergism means that the sum of the two components is greater than the arithmetic sum, so that the effect of the two components when given together is greater even than just the sum of the two parts. HIS HONOUR: One accelerates the other or - - - ?---Correct. Perhaps you had better just tell me what is the relationship between the history of smoking and the effect of the inhalation or ingestion of a significantly radio-active particle?---It's a very, very well established fact that - the best data comes from radium miners who also smoke and their incidence of lung cancer is much higher than the men to either only smoke or only exposed to radium and so from that data, and there are many other examples in the medical literature, there is strong evidence of synergism in relation to carcinogenesis. In respect to the kidney, the data is simply not available. We just don't know but on the basis of carcinogenesis in other solid organs it seems a very logical assumption to make. I am not aware of any epidemiological evidence that addresses the point in relation to cancer of the kidney." He later said: "There are two strong carcinogens acting here. It's impossible to say which is more important but it is possible on the basis of other epidemiology to say that having both acting together is far worse that just having one by itself." 202. Dr Kefford dismissed as irrelevant epidemiology and the extensive evidence of epidemiologists given on behalf of the Commonwealth, to which I shall refer later. He expanded on his assertion as to their irrelevance in the following passage:- "Having read those reports, does it change your view in any way?---It does not. Do you have anything to say as to the relevance of those reports?---Yes I do. I think one has to make a very clear distinction between epidemiological studies and the very specific and individual circumstances affecting one person. The study of - the science of epidemiology is also removed from the recent understanding of the molecular biology of the genesis of cancer and for those two reasons I have serious reservations about the conclusions of these reports. HIS HONOUR: When you say a recent understanding could you be a little more specific about that?---Yes, your Honour, I refer specifically to the discovery that the causes of cancer in nearly all cases of solid tumours of which renal cell carcinoma is one are due to mutations in tumour suppressor genes and in genes which regulate DNA repair." 203. He further expanded upon these statements by referring to "the important point ... that individuals can be predisposed to carcinogenesis by their genetic make-up". Such persons have a "particular predisposing genotype" which, he said, was "fairly recent knowledge". He went on, as follows:- "Now, it's an example of the fact that within our community there are individuals who might smoke 80 cigarettes all their life and never get cancer because they have a protective constitutional genotype. There are other individuals who because of the nature of their genetic makeup are predisposed to the carcinogenic effect of radiation or carcinogens in the environment such as cigarette smoke. Furthermore, this constitutional makeup doesn't predispose to cancer as a whole but to cancer in specific target organs. So that one person who smokes might (get) cancer of the larynx and never get lung cancer, another might get cancer of the bladder and never get lung cancer. So that the molecular understanding of carcinogenesis is at variance with epidemiological studies. All that epidemiology can tell us is, it can identify in large populations what are risk factors in the environment, that's all it can do. It can't tell us any more about the precise quantity of risk in an individual. For me to smoke five cigarettes a day might be absolutely disastrous. Whereas in a population study, it would appear to be a minimal risk. So I guess that's the point." 204. In relation to Cubillo himself, Dr Kefford agreed that he could not point to any evidence to suggest that he had any unique susceptibility to radiation induced renal cell cancer. He said "all I can say is that I have no evidence that Mr Cubillo has a particular susceptibility to radiation. I just don't know, no one does, and there is no way of finding out". 205. Dr Kefford was extensively cross-examined and material of a countervailing nature was put to him from the reports of expert witnesses to be called in the respondent's case. There is no need to set out this material in these reasons. I finally put to him the following question and received the following answer:- "Well, can I ask you this, because I have got to know, what is the theory that you propound leading from Mr Cubillo's exposure in his activities at Maralinga to plutonium or polonium to his developing of a renal cell cancer some whatever it is, 20 years later ?---My theory is that during his activities in Maralinga, particularly when he discarded radio protective clothing, and particularly when he was doing duties such as sweeping up contaminated sites with a circular broom and working in contaminated areas and eating and so on, that on one occasion or several occasions, wiping his hand with the back of his glove or ingesting sandwiches or whatever, or breathing in that dust, a particle of radioactive material entered his body, it circulated through the blood stream, a large proportion of it was probably distributed to his lungs and other organs as we have shown. A small proportion of it was distributed to the renal tubules and parenchyma cells and caused a carcinogenic mutation in a critical tumour suppressor gene in a cell, and with the long induction period known for that to become manifest as a detectable mass, it took 18 years for that tumour to be clinically detectable and furthermore that the fact that he was a heavy smoker may have in some way as yet undetermined, predisposed to that carcinogenic event through additional mutations in other genes within those critical cells and therefore assisted the whole process, but that part of it I don't know. It is equally possible that radiation had nothing to do with it and that cigarette smoke and carcinogens in it were sufficient to cause the event, however, there is no other evidence of severe tobacco injury in the man, but he was a heavy smoker. I don't know what was the most important contributing factor, but both seem very plausible to me." 206. He further said that an inhalation or ingestion of the isotope would be quite sufficient to give a carcinogenic dose to the kidney, even if the inhalation or ingestion occurred only on one occasion. However, in relation to plutonium 239 as against polonium he appeared to be of the view that the theory was on firmer ground if the exposure was more extensive. He gave the following evidence:- "Well, I would say certainly an eight hour period, based on Robotham's calculations, to be absolutely confident, I suppose you would say a two-day period of working in those dusty conditions would give, given the distribution of plutonium to the kidney, still a dose that would conceivably be carcinogenic. So it is a dose that could be cumulative over a period of even a day or so?---Sure. So that one has the picture of it coming in particle by particle, as it were, over a period of time and accumulating through the distribution system and renal area?---Absolutely. Kicking off this whole unfortunate process?---Exactly." 207. Dr Kefford's evidence, it may be said, is in conflict, in every significant aspect, with the medical evidence and the epidemiological evidence called on behalf of the respondent. Apart from that conflict it has some obvious inherent difficulties. In the first place, despite his insistence from time to time on the irrelevance of the size of the radiation dose, it is quite clear that Dr Kefford has been influenced not inconsiderably in his overall approach and assessment by the material of Mr Robotham's reports and the general picture painted by the lay evidence. Mr Robotham's estimates, which were entirely hypothetical, suggested a heavy dose of radiation in the order of 2 sieverts. As I have found, the actual potential dose was very significantly smaller. It is very difficult to reconcile the doctor's single minuscule application of alpha emitter radiation with what he said in the passage last quoted. Moreover, he made it abundantly clear that he had no real concept of the effect of radiation from a health physics point of view. I consider that he shifted ground on this topic from time to time in a manner that betrayed a considerable absence of confidence in this area. Moreover, I am left with a clear impression that he had in his mind, at all relevant times, a picture of the applicant working in a dangerous, highly radioactive dust cloud. This picture could readily enough be obtained from the lay evidence and from Mr Robotham's report. The facts of the matter were, however, significantly different as the evidence of Mr Davy has demonstrated. 208. However, Dr Kefford's evidence puts forward a somewhat beguiling theory, for the testing of which, it is necessary to have regard to the evidence called by the respondent. 209. It is convenient to commence with the evidence of Dr Richard Fox. Dr Fox is a practicing oncologist with a most impressive curriculum vitae. Since 1985 he has been the Professor and Director of the Department of Haematology and Medical Oncology at the Royal Melbourne Hospital and University of Melbourne. He is an Honorary Consultant in cancer medicine at the Royal Prince Alfred Hospital in Sydney and Honorary Professorial Associate at the Ludwig Institute of Cancer Research, the Melbourne Tumour Biology Branch at the Royal Melbourne Hospital. He was instrumental in the formation of the Australian Cancer Network, a national body which deals with cancer issues at a national level, cancer now being the major cause of death in the Australian community. He has served on many learned committees and been an author or co-author of numerous learned publications in relation to cancer, its causes and treatment. He has had very wide experience in cancer research in the clinical, medical and epidemiological fields. He has lectured extensively on cancer related topics. He has been intimately involved in all issues relating to understanding the significance of the relationship between tobacco smoking and cancer and has followed for a considerable period of time the main scientific literature in relation to this topic. Dr Kefford was one of his students in the 1970s. He took issue with Dr Kefford's evidence in many major respects. 210. In the first place, he was entirely opposed to Dr Kefford's dismissive view of the value of epidemiology in this case. He clearly held the view that the material collected by way of epidemiological research is of fundamental importance in the discernment of links between cancer in various parts of the human body and agents to which the body is exposed. He rejected Dr Kefford's opinion that epidemiology has been relegated to a minor insignificant role because of advances made in the field of molecular biology. In his view, which I accept, molecular biology is really only beginning to provide explanations of connections that epidemiological studies have pointed to for many years, particularly in the area of tobacco smoking and cancer. He stated that the two fields of science are complimentary; it is not a matter of the later superseding the earlier. In particular, Dr Fox positively disagreed with any theory supposedly founded upon discoveries of molecular biology that 100,000,000th of a "speck" of the radionuclide plutonium 239 could reach the kidney with carcinogenic effect, when the results of very extensive and carefully controlled epidemiological studies point to the impossibility of such an occurrence. 211. Dr Fox was asked to make specific comment on the following statement made by Dr Kefford in his evidence: "... the causes of cancer in nearly all cases of solid tumours are due to mutations in tumour suppressor genes and in genes which regulate DNA repair". Dr Fox replied as follows:- "Well, in general, most cases now of cancer are believed to be due to mutations in various genes. These are either onco genes which are genes that promote cancer or tumour suppressor genes which have sort of been holding things in abeyance which actually turns them into an onco gene, and as well there are repair genes and a whole series of other genes that are involved in control of cell cycle progression, etcetera, etcetera. It's a very complex business and most cases of a particular malignancy evolve over a long period of time and have to accumulate a series of these mutations. But I do not know why this matter was raised in terms of the relationship to the epidemiological reports. It doesn't nullify, it just enables us to understand mechanisms by which carcinogens can act." 212. He was then asked the following question and gave the following answer:- "Is there anything in particular about this point concerning cancer being due to mutations that makes the Cubillo history special or different in any way?---No, there's nothing that we can see that's special about Mr Cubillo and as I said, there are another 20 Mr Cubillo's out there with renal cell cancer and a whole series of other cancers just on the fact that they are Australians in this particular day and age. I think where Rick (Kefford) has got to is, I really think he had for various reasons concluded absolutely that Mr Cubillo's renal cancer was due to radiation exposure and was then simply trying to explain how radiation might have caused that." 213. I should perhaps indicate that the last sentence in this passage from Dr Fox's evidence confirmed a view I had tentatively formed that a great deal of Dr Kefford's evidence was rationalisation. He was seeking to support by a process of reasoning a predetermined view. 214. Dr Fox made a clinical examination of Mr Cubillo on 13 December 1994. He received a history consistent with what I have already recorded. Recent x-rays of relevant areas were normal and Mr Cubillo was able to carry out normal daily activities. He told Dr Fox that from age 16 he had smoked 20-40 cigarettes a day, stopping in 1982 after his kidney operation. At that stage he was drinking "some 6-8 schooners of beer a day". 215. Dr Fox provided a report and gave oral testimony. He commenced by considering the incidence of cancer in the general community, pointing to the fact that in Australia there are approximately 60,000 new cases of cancer each year, the incidence being closely related to age. The relevant statistics indicate that "an individual in passing from the age of 50 to 59 has, on average, a 1 in 20 chance of developing a cancer during that decade. In moving from the age of 60 to 69 the risk doubles, i.e. a 1 in 10 chance, and similarly, going from age 70 to 79 the risk doubles again". Accordingly, the occurrence of cancer in a number of the ordinary population was predictable without recourse to any particular category of causation. It is clear that Dr Fox held the view that Cubillo's renal cancer could be accounted for in this way. 216. However, on the basis of epidemiological studies which he regarded as producing valid results, Dr Fox was able to posit the likelihood that Cubillo's cancer was attributable to his heavy smoking up to the time that it manifested itself in 1982. It may be remembered that in his first report Dr Kefford said that "smoking is a definite risk factor and about 30% of renal cell carcinomas are caused by smoking". In these circumstances, it is quite unnecessary to set out in these reasons the detail to be found in Dr Fox's report as to various studies which have implicated cigarette smoking as a risk factor in the occurrence of renal cell carcinoma in men and women. He instanced no less than six such studies. For instance, the study referred to as the Sharpe Study published in the Canadian Medical Association Journal in 1989 found that smoking more than 20 cigarettes per day was associated with the presence of metastatic renal carcinoma. Cubillo's consumption of cigarettes had been well in excess of this for over 35 years before his carcinoma was diagnosed. 217. Conversely, Dr Fox was satisfied that other important studies indicated that there was no significant association between exposure to ionising radiation and the occurrence of renal cell carcinoma. Of course, it has already been observed in these reasons that the extensive research which produced the information contained in the ICRP tapes had demonstrated the absence of any such association. 218. Again, Dr Fox set out in his report and gave oral evidence of numerous reported studies which point to this conclusion. Amongst these reports are those undertaken in respect of atomic bomb survivors of Hiroshima and Nagasaki, a cohort study of great scientific renown referred to as the Life Span Study, to which I will refer later. Also included were the studies conducted by Sir Richard Doll, generally regarded as the world's most esteemed cancer epidemiologist, of participants in the United Kingdom nuclear weapons tests in the Pacific which, of course, included the Maralinga tests. Both Professor Schull, who was charge of the Life Span Study, and Sir Richard Doll gave evidence in these proceedings to which I shall refer later. The result of these studies was that there was no appreciable risk of kidney cancer from exposure to ionising radiation. 219. Dr Fox summed up the "relative risk of induction of cancer of the kidney by radiation versus smoking" in the following way:- "Based on the data from survivors from the atomic bomb explosions in Nagasaki and Hiroshima, and other groups exposed to radiation, the risk of renal cancer is relatively very low or non-existent. However, there is a consistent association of induction of kidney cancer and smoking depending on the intensity and duration of smoking a factor of two to three-fold." 220. He went on the express the opinion in relation to kidney cancer that:- "In the final analysis, the scientific data reviewed above do not show ionising radiation to be a significant cause of carcinoma of the kidney. In particular, the atomic bomb data from Nagasaki and Hiroshima when one removes bladder cancer from the analysis, shows a slight but not significant increase. In particular, follow up studies of UK participants in the Australian A-bomb tests demonstrate there was no increased risk for development of kidney cancer. Therefore, in Mr Cubillo's case I cannot support the contention that his potential exposure to radiation in the atomic bomb testing in Australia was responsible. He clearly was exposed to heavy cigarette smoking for a long duration and this, by a factor of up to two-fold, increased his risk of the development of cancer of the kidney." 221. Furthermore, Dr Fox rejected Dr Kefford's proposition that in the case of the induction of renal cell carcinoma there could be a synergistic effect between prior heavy tobacco consumption and the effect of low dose radiation. He expressed the view that synergy was absolutely irrelevant to the present case. Whatever might be the situation as to some interaction between smoking and radiation in the case of lung cancer, Dr Fox was of the view that there was no basis for postulating anything similar in the case of renal cell carcinoma. This was because, in his words, "you don't have a radiation effect in the first place". He said, in relation to the synergy theory of Dr Kefford, "why develop a special theory for Mr Cubillo? I mean it just doesn't make sense that it would have picked out Mr Cubillo and you have this elaborate theory when there is no evidence that it is carcinogenic - that renal cancer can be caused by radiation in the first place". 222. Dr Fox also refused to ascribe any relevance to Dr Kefford's proposition that Cubillo might have some particular susceptibility to the development of renal cell carcinoma through exposure to ionising radiation. In his view, there was simply no evidence of radiation causing renal cell carcinoma, nor of the existence of any particular individuals that were prone to develop radiation induced cancer. 223. Dr Fox was an impressive witness. He was not cross-examined on any of his evidence. I prefer his evidence to that of Dr Kefford in all areas in which they are in conflict. 224. The next witness to whom I should refer is Professor Brett Delahunt, an anatomical pathologist whose present position is Associate Professor of Pathology at the University of Otago, New Zealand. He is a urogenital pathologist and a recognised expert on renal cell cancer. He also has a most impressive curriculum vitae and has been the author and co-author of a very large number of learned papers in the area of his specialty. I found him to be an enormously impressive witness. By use of appropriate diagrams he was able to explain clearly the nature and situation of a renal cell carcinoma in a way which cast considerable doubt upon the accuracy of Dr Kefford's evidence in this regard. He provided a comprehensive report and gave oral testimony. He had had access to Cubillo's hospital records and the medical notes in relation to his nephrectomy operation in 1982. He had also examined 11 tissue sections taken from Cubillo's tumour, adjacent kidney and associated structures. He also viewed the histological slides relating to the metastatic carcinoma in Cubillo's lung. He was satisfied that this tumour had spread from the original renal cell carcinoma. 225. Professor Delahunt gave an exposition of factors suspected to play a role in the aetiology of renal cell carcinomas, the details of which need not be repeated here. Significantly, however, he stated his belief that the fact that Mr Cubillo had been a heavy smoker for a large period of his life was "a highly significant factor in the development of Mr Cubillo's tumour". 226. Professor Delahunt gave specific consideration to radiation exposure as a risk factor for renal cell carcinoma. In doing so he provided a summary of the more important studies as to the carcinogenic effects of ionising radiation. The Professor regarded the Life Span Study of the Japanese A-bomb survivors as one of the most, if not the most, important epidemiological study ever undertaken. He spoke of it in his report as follows:- "Long term follow-up of survivors from the atomic bombs dropped on Japan at the close of the Second World War provide valid data concerning risk of developing cancer associated with exposure to radiation. There is almost complete case ascertainment of deaths from the 120,000 individuals registered for follow-up in 1950 and radiation dosage has been estimated for 95% of registered subjects. In these studies increased risk for renal cell carcinoma was not observed although radiation dosage of 1 Gy was associated with a relative risk of 2.0 for malignancies of the urinary tract. Urinary tract malignancies consist predominantly of transitional cell carcinomas which are tumours of the lining epithelium of the renal pelvis, ureter and bladder totally unrelated to renal cell carcinoma. The 1994 update of the Radiation Effects Research Foundation Life Span Study reported no significant radiation related risk for cancers of the kidney for survivors of the Nagasaki and Hiroshima atomic bombs." 227. Similar results were referred to in other studies. I shall not set them out here. 228. Professor Delahunt also dealt with renal tumours induced by radiation in experimental animals. He had sought to induce renal tumours in experimental mice and rats. The use of ionising radiation for this purpose had, however, proved unsatisfactory because the doses that were required were so high that complete failure of the animal's physiological system occurred prior to the development of any tumour of the kidney. In this regard he gave the following evidence:- "Well, does that say anything about radio-sensitivity of the kidney in these animals?---Yes, the kidney is not a radio-sensitive organ. It is an organ that is perhaps a little more sensitive than the heart, but the heart is an organ which is not radio-sensitive and if you irradiate it, tumours don't occur. If you irradiate the kidney at very very high levels you will produce tumours, but you'll produce few tumours and the level of irradiation is such that it effectively destroys the substance of the kidney." 229. It was also ascertained that the level of radiation required to produce tumours was associated with sclerosis or scarring of the kidney which implied "that the damage to the kidney by the radiation is such that the blood supply is compromised and as a result of that scarring occurs and the normal structures of the kidney are lost". This knowledge, gained from animal experiments, could be transposed to human beings because of a basic similarity of the organs. A high dose of irradiation to the human kidney would be productive of similar sclerosis quite visible under the microscope and associated with the loss of renal function. An examination of the slides of Cubillo's kidney disclosed no sclerosis and, consequently, Professor Delahunt concluded that there was no evidence that the kidney had been exposed to high doses of radiation. 230. In general, Professor Delahunt was of the opinion that the most important aetiological factor in the development of renal cell carcinoma appeared to be cigarette smoking, that being the one predisposing factor for which there was consistent and strong evidence. Conversely, there was little evidence to associate radiation with the development of renal cell carcinoma except in very high doses, such high doses being associated with sclerosis of the kidney. 231. He considered that, in Cubillo's case, cigarette smoking was "a significant cause of his renal cell carcinoma". Alcohol consumption was also a possible contributory factor. He emphasised by reference to particular experiments performed upon laboratory rats that "the doses required to induce tumours that resemble renal cell carcinoma in animals were really quite high in comparison, especially to the radiation doses which were recorded as being received by the applicant". Also, sclerosis developed before any tumour formation occurred, the tumours occurring over a time span comparable, having regard to the much shorter life of a rat, to the time span required for the development of such tumours in a human being. It was the Professor's opinion, quite contrary to that expressed by Dr Kefford, that had Cubillo received a radiation dosage sufficient to cause renal cell carcinoma, he would have suffered a severe systemic reaction involving radiation burns and possible hair loss and loss of immune function together with obvious sclerosis to the kidney. In the absence of any of these features, Professor Delahunt did not believe that ionising radiation had been a contributing factor to Cubillo's renal cell carcinoma. 232. A number of passages from Dr Kefford's evidence were put to Professor Delahunt for his comment. I do not propose to set this material out in these reasons. The answers he gave completely satisfy me that I should prefer the evidence and conclusions of Professor Delahunt to those of Dr Kefford wherever they are in conflict. His evidence, in my opinion, shows that Dr Kefford's theorising was shallow, unsubstantiated and unacceptable. 233. Many of the highly qualified scientists who gave epidemiological evidence on behalf of the respondent in this case were also qualified to express medical opinions. I do not propose to set out these opinions, except to note that none of the opinions given supported Dr Kefford's views. They either cast severe doubt upon them or refuted them. However, because of his extraordinary eminence in the field of epidemiology and cancer research, I shall refer to some of the evidence given by Professor Doll. 234. The Professor gave evidence as to the risk to the kidney of inhalation or ingestion of plutonium 239. He agreed that the ICRP tapes indicated that in relation to any particular inhalation or ingestion of plutonium 239 100,000,000 parts would go to other organs of the body and only one part would go to the kidneys. In this context he gave the following evidence:- "To double the normal risk of developing kidney cancer any such dose would have had to be enormous and it would certainly have had to effect the risk of cancer in other organs as well causing in the case of any ingested plutonium much higher incidences of cancer in the lung and bone. I was not suggesting that Mr Cubillo himself would have developed cancer of the lung or bone. What I was intending to say was with the amounts of plutonium that were about if one was to assume that any would have affected the kidney, the amounts would have had to be so enormous that many other people in Maralinga would have had to have gone down with cancer of the lung and cancer of the bone, where plutonium is specifically deposited. It is another way of saying that only one hundred millionth part of plutonium that is ingested will end up in the kidney. So you would not see the plutonium exposure for the reasons that you have given as being a significant contribution to any ionising radiation exposure for Mr Cubillo at Maralinga?---I cannot see that plutonium could have contributed to the risk of his developing cancer of the kidney." 235. This passage, in fact, referred to some material provided by Professor Doll in a written report which was also in evidence. There is no need to refer to that earlier material as the essential matters concerned are in the passage quoted. For Cubillo's cancer to have been attributable to ingestion of plutonium 239 there would have to have been such an abundance of the isotope present in the areas he worked in at Maralinga that it would necessarily follow that there would have been a high incidence of lung and bone cancer amongst those present, these being the target organs for plutonium 239. The fact that this had not occurred was a clear indication that plutonium 239 was not present in sufficient quantities to have any effect upon Cubillo's kidneys. Later evidence given on the same topic was as follows:- "You exclude any possible connection with plutonium?---Yes, I do completely, your Honour." And again, "I think you regard the contribution infinitesimal for plutonium ... if any at all it would be infinitesimal. Infinitesimal is small." 236. He later said that such an infinitesimally small exposure of the kidney to plutonium 239 "should be ignored in relation to the possibility of producing cancer in the body". It was not a matter "as against smoking ... as of any significance at all". 237. Of particular significance, in my view, was the evidence that Professor Doll gave in relation to dose. It will be remembered that it was integral to Dr Kefford's thesis that the amount of the radiation dose was, for practical purposes, irrelevant. In effect, he said that any level of radiation, however small, provided that it got to the kidney, could be carcinogenic. A particular passage of Dr Kefford's evidence that related to Mr Robotham's calculation of dose was put to Sir Richard for comment. That passage read as follows:- "I place little reliance on the level of exposure that was measured. I don't think it's terribly relevant, I really don't." 238. Sir Richard was then asked the following question and gave the following answer:- "Sir Richard, in relation to radiation and the measure of the possible effects of that on cancer, that is exposure there as against other factors, what would you say about that particular answer?---Well, I found it quite an astonishing remark. There is, in my experience, completely uniform agreement that as far as the induction of cancers other than leukaemia are concerned, the risk is directly proportional to the dose. The only difference of opinion amongst people at any rate that attend the meetings of United Nations Scientific Committee on the Effects of Atomic Radiation is whether low doses have any effect at all. There are scientists who argue that very small doses of the order that we have been considering, natural background and doses of that order, don't have any effect at all because of the cells' capacity to repair the damage. I'm not myself one that holds that view but that is the only element of controversy that I am aware of at all. Otherwise there is unanimous agreement that risk is minimally proportional to dose, with some reduction in the effect at very low doses and possibly some people argue, no effect at all. So, Sir Richard, is it fair to say that in relation to any calculation by science or otherwise as to the relationship between an exposure to ionising radiation and a possible carcinoma, in this case an RCC (renal cell carcinoma), the first matter that needs to be determined is the issue as to whether there has been exposure and a level of that exposure?---Yes, the level of that exposure to the tissue at risk." 239. When one considers, as the evidence demonstrates, the level of expertise and the international renown of the scientists attending the meetings referred to in this passage, Sir Richard's description of Dr Kefford's evidence as "quite an astonishing remark" takes on an even greater significance than it otherwise would have had. 240. Sir Richard was also asked to comment upon Dr Kefford's evidence as to the potential synergistic effect of tobacco smoking in combination with exposure to ionising radiation, in relation to the production of Cubillo's renal cell carcinoma. He gave the following answer:- "Well, this question of the possible synergism of different factors in causing cancer is one of considerable scientific interest and I think most people accept that there are synergistic effects in the sense that the development of cancer is a complex process requiring several changes in a cell and different agents may cause different changes at different times so that they can - different agents can work together in causing cancer. We don't have very much quantitative evidence on - or even qualitative evidence - on the effects of synergism but there is an increasing amount and as Dr Kefford pointed out, some of the evidence is from the radon miners whose smoking histories are known and in whom one can see that the combined effect of exposure to radon and cigarette smoke is greater than the effect of radon in non-smokers - is greater than the additive, the addition of the effect of radon in non-smokers or cigarette smoking in the absence of exposure to radon. It would be nice if one could say the two factors multiply each others effects and that has been a common hypothesis until recently but it is becoming clear that they don't, in fact, quite have as great an effect as that. But in relation to the present case, the possibility of synergism, and I would quite readily accept that radiation and smoking may act synergistically in the production of cancer, but the effect of each factor quantitatively can only be assessed by seeing its effect in the absence of the other. And the estimates of the effects of radiation that we have made as a possible cause of cancer of the kidney indicates that the increase in risk for the sort of small doses of which we have been talking, is very small - of the order of one or two per thousand. Now, those estimates have been obtained from populations who are, or most of whom, are smokers so that the synergistic effect is already seen in that estimate. What one means by saying that smoking and radiation acts synergistically in producing the disease is that if radiation causes a risk of, let's say 2 per 1000, in the absence of smoking multiples the risk from other factors by 1.002, it will have the same quantitative effect of the smoker. It will increase the risk by, again, another proportion of 2 per 1000 whereas the risk of smoking in the absence of radiation, if that causes a 500 per 1000 risk in the unexposed to radiation, it will cause 500 in a 1000 times increase to the risk in a person that's exposed to radiation. Of course, one can't talk about people not being exposed to radiation because we are all exposed to background radiation and as far as I've been able to assess in the present situation, the amount of radiation to which this individual has been exposed is not substantially great, is probably less, than the amount of - almost certainly less - than the amount of exposure from natural background radiation. So to suggest that there is any equality between these two factors and their contributions to the production of the disease, even if they are acting synergistically, is just in my opinion, erroneous." 241. In my view, this passage on its own, and without regard to similar expressions of expert opinion from other witnesses in the respondent's case, is sufficient to put paid to Dr Kefford's reliance on synergy in this case. 242. In relation to Dr Kefford's hypothesis that Cubillo might have "a specific tissue sensitivity" predisposing him to carcinoma of the kidney from exposure to very low doses of radiation, Sir Richard had this to say in his evidence:- "I think it is impossible ... for the simple reason that people would have died long ago from natural radiation. This little bit of plutonium 239 that is being suggested might get through to the kidney, would not be the first exposure of the organ to radiation. They have been exposed to radiation their whole lives. It would be an equivalent amount to what you would get from background radiation in effect?---Indeed, your Honour, yes. I see?---And they would've been dead long ago if they had tissue susceptibility to radiation of the sort he is talking about." 243. When discussing the distribution of plutonium 239 in the human body in accordance with the data of the ICRP tapes, Sir Richard elaborated on this point as follows:- "It tells you something that is very important in relation to what we're discussing. It tells you about the distribution in relation to the body and we know that, as far as the kidney is concerned, the dose would have to be enormous to produce, to give a dose to the kidney which was anyway comparable to the background radiation that he's already exposed to." 244. I am quite satisfied that this evidence effectively removes from the case any consideration that Cubillo's renal cell carcinoma could be attributed to a "minuscule" quantity of alpha emitting radionuclide impinging upon a specially sensitive kidney. EFFECT OF THE MEDICAL EVIDENCE 245. In my opinion, the medical evidence called on behalf of the respondent, which I have sought to set out in fairly summary form above, effectively disposes of Dr Kefford's theory that Cubillo's renal cell carcinoma could have been caused by the inhalation or ingestion of a small particle of plutonium 239 whilst he was performing his duties at Maralinga. I am satisfied that the evidence points inevitably to the cancer's being either idiopathic in origin, i.e. not ascribable to any particular cause, or to its being causally related to Cubillo's history of heavy smoking. The weight of evidence compels the view that it was not caused by radiation at Maralinga. 246. The applicant's case, therefore, must necessarily fail. Before I part with it, however, I should make reference to some other significant aspects of the case. The first is the extensive epidemiological evidence called on behalf of the respondent. THE EPIDEMIOLOGICAL EVIDENCE 247. The whole of this evidence was called on behalf of the respondent. It was extensive and complex. It was presented by witnesses of the highest international reputation. Except in some peripheral ways it was uncontested. I accept it in its entirety. 248. In effect, the only response made to it on behalf of the applicant was that it was irrelevant. This could only be described as a bold submission made, apparently, on the basis that Dr Kefford's evidence overwhelmingly indicated that Cubillo had been placed at risk of incurring the renal cell carcinoma by the inhalation or ingestion of a particle of plutonium 239. The existence of this risk required that all the epidemiological evaluations of radiation risk be seen as having no real significance in the case. They were simply beside the point. Studies of the statistical relationships between radiation and various types of cancer, one of which has extended over 50 years, could simply be swept aside as having no bearing upon the outcome of this case. 249. There is no substance in this submission. I reject it. The epidemiological evidence in the case adds support to the respondent's medical evidence which I have already found is sufficient to resolve the case in its favour. In these circumstances I do not propose to deal at length with this material. However, the volume that was presented requires that I make reference to the most significant parts of it. 250. Essentially, epidemiology relies upon statistical analysis of populations to estimate the risk of developing particular diseases as a result of exposure to particular agents. It is a highly developed science involving complex statistical and mathematical concepts. These concepts have been explained in the evidence at considerable length as has the methodology employed in individual studies. The relevant material is contained in the extensive reports of the scientists who gave evidence before me and in their equally extensive oral testimony. Before referring to salient parts of it, it is convenient to set out a brief explanation of some of the terms associated with it. 251. Two such terms are "absolute risk" and "relative risk". 252. "Absolute risk" refers to the excess number of incidences of disease, above those "normally expected" in the population being studied. "Normally expected" means in the absence of exposure to the particular agent being studied. In radiation studies, excess incidences are often stated in terms of the number of years the individual, or group of individuals, have lived following exposure. The unit used is person-year-gray (PYGy). For example, a person who survived 5 years after exposure to 0.5 Gy would contribute an excess of 5 x 0.5 or 2.5 PYGy. 253. "Relative risk" may be expressed in terms of a "relative risk ratio" or in terms of "excess relative risk". A "relative risk ratio" is the ratio of the risk in one population to that in another. A relative risk ratio of 1 means that the disease is no more frequent in the exposed population than in the unexposed population. "Excess relative risk" refers to the difference between the observed relative risk and 1, being the value expected in the absence of risk. In other words, if a disease is no more frequent in an exposed population than in an unexposed population, the excess relative risk would be expressed as 0 (zero). To further illustrate these terms, a relative risk ratio of 2 means that the disease is twice as frequent in the exposed population than in the unexposed population. In these circumstances, the excess relative risk would be expressed as 1. 254. Results may be further characterised as "statistically significant" or "statistically non-significant". A result is "statistically significant" if the probability that it is due to chance or random variation is 1 in 20 or less. This probability is conventionally written as "p is less than or equal to 0.05". Conversely a result will be characterised as "statistically non-significant" if the probability that it is due to chance or random variation is "p is greater than 0.05". 255. A complication is introduced into the concept of statistical significance by the use of the terms "one-sided" and "two-sided". Conventionally, p = 0.05 is interpreted to mean that there is a 1 in 20 chance that the difference between the incidence of disease normally expected and the incidence of disease observed, could occur in either direction. Unless "p" is qualified this is what it is taken to mean. However, when there is a prior hypothesis that the incidence of a disease in a population exposed to a particular agent will be higher than the incidence of that disease in an unexposed population, it is thought more appropriate to only cite the probability of a excess of incidences being found above those normally expected. 256. Another way of expressing whether or not a result is statistically significant is in terms of confidence levels. A 95% confidence level is equivalent to p is less than or equal to 0.05. That is, the probability that the result is due merely to chance or random variation is 1 in 20 or less. Confidence levels are often expressed in conjunction with confidence limits. Confidence limits define the range of results supported by the data at the chosen confidence level. For example, a study of the difference between the incidence of a disease observed in an exposed population and the incidence observed in a non-exposed population may be reported as lying within the confidence limits of 2 and 4 at a 95% confidence level. This means that the reader can be 95% sure that the true relative risk of developing cancer after exposure to the agent lies somewhere between 2 and 4. 257. Highly significant evidence was given by Sir Richard Doll. He is of such eminence in the field of epidemiology that it is appropriate that I make some reference to his curriculum vitae. 258. Sir Richard Doll graduated with a Bachelor of Medicine from the University of London in 1937. He went on to be awarded the degrees of Doctor of Medicine and Doctor of Science from the University of London in 1945 and 1958 respectively. He holds honorary degrees of Doctor of Science from a number of universities including Harvard, London and Oxford and of Doctor of Medicine, also from a number of universities, including Oxford University. 259. His professional appointments have been numerous and in relation to cancer research have included the chairmanship of the Medical Research Council's Cancer Coordinating Committee and of the Institute of Cancer Research Management Committee, membership of the UK Coordinating Committee on Cancer Research, Radiation and Cancer Subcommittee, the Scientific Council of the International Agency for Research on Cancer and the Council of the International Union Against Cancer. He is also an honorary member of several national and international associations including the American Association for Cancer Research, the American Epidemiological Society, the International Epidemiological Society, the International Association of Cancer Registries and an honorary fellow of the Society for Radiological Protection. 260. He has received awards and professional distinctions too numerous to relate for his contributions to medical research, particularly in the area of cancer research. During his career he has held, amongst others, the posts of Regius Professor of Medicine at the University of Oxford (1969-1979), Warden of Green College at the University of Oxford, a post-graduate college with a special interest in clinical medicine (1979-1983) and Director of the Imperial Cancer Research Fund's Cancer Epidemiology and Clinical Trials Unit (1978-1983 and 1987-1989). 261. He is currently an honorary member of the Imperial Cancer Research Fund's Cancer Studies Unit in Oxford. He has also been a consultant in epidemiology to the National Radiological Protection Board since 1985 and a member of the British Delegation to the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) since 1989. 262. His major areas of research have included studies of the health effects of ionising radiation, smoking and asbestos exposure. He has also studied the causes of lung cancer, leukaemia and peptic ulcer. He has published over 400 articles since 1936, and it would not be inaccurate to say that his professional reputation in the field of epidemiology is unsurpassed. 263. One of Sir Richard's major areas of research has been a study of mortality and cancer incidence in UK participants in the UK atmospheric nuclear weapons tests and experimental programs. The study was commissioned by the British Ministry of Defence in 1983 after a number of claims in the British media that people who had taken part in the tests had experienced a high incidence of leukaemia. Sir Richard and Dr Sarah Darby, who was also associated with the Imperial Cancer Research Fund, carried out the study in conjunction with the National Radiological Protection Board. 264. All together a total of 21,358 men who had participated in the tests and experimental programs that were carried out in Australia and the Pacific Ocean between 1952 and 1967 were identified from archives of the Ministry of Defence and were followed up to 1 January 1991 ("the participants"). Another 22,333 men who had served in tropical or sub-tropical areas other than the test locations during the period when the tests were carried out were also selected from the archives to serve the function of a control group ("the controls"). These controls were selected in order to match the participants as closely as possible by service (army, navy, air force, or employer if civilians), rank (officer, other rank, or socio-economic class if civilian), year of birth, year of enlistment (or employment) and year of discharge (or termination). 265. The causes of mortality and the incidence of cancer in the participants was determined from national records and compared with the causes of mortality and cancer incidence in the controls. In addition, the causes of mortality in both groups was compared with what would have been expected if the men had experienced the same causes of death as those of men of the same ages in England and Wales as a whole, during the same period ("the corresponding national population"). 266. Causes of mortality were compared first, over the whole period of follow-up and secondly, ten or more years after entry to the study. This was because a material increase in the risk of developing cancer after exposure to radiation is seldom seen in under ten years. The results were expressed in the form of standardised mortality ratios ("SMRs"), that is, mortality ratios expressed as a percentage of those expected from the corresponding national mortality rates. 267. Over the whole period of follow-up the participants were found to have had a slightly lower mortality from cancer than the controls (the SMRs were 83 and 86 respectively), but they had exactly the same mortality rate from all causes put together (the SMR was 84 for both groups). 268. Comparisons made ten or more years after entry to the study showed that the participants once again had a slightly lower mortality from cancer than the controls (the SMRs were 84 and 87 respectively), but they had exactly the same mortality rate from all causes put together (again the SMR was 84 for both groups). 269. Mortalities in both groups from all causes and all cancers over the whole period of follow-up and ten or more years after entry to the study were lower than the corresponding national population (shown by the fact that the respective SMRs were all less than 100). This was explained by the fact that the requirements for recruitment to the armed services means that such recruits are, generally speaking, healthy people when they join up. The small differences between the participants and the controls in relation to mortality from cancer were concluded to be easily accounted for by chance. 270. Sir Richard concluded that these results indicated that participation by UK servicemen in the UK atmospheric tests of nuclear weapons did not effect their expectation of life at all, as far as one can detect it, neither their total expectation of life nor their expectation of living without cancer. In fact the participants in the nuclear test program had a healthier profile than the population as a whole in relation to mortality from both all cancers and all causes. 271. Causes of mortality were also examined to reveal any differences in mortality rates for 27 different types or categories of cancer. Of relevance to this case are the results in relation to leukaemia, because it is the type of cancer most readily induced by ionising radiation, and for kidney cancer, because of its special relevance to Cubillo's case. 272. Mortality from leukaemia was examined over the whole period and for the period 2 to 25 years after entry to the study, as leukaemia induced by irradiation tends to occur sooner than other types of radiation induced cancer and the risk is highest in the relatively early period. For the period 2 to 25 years after entry to the study, the participants had a significantly higher mortality from leukaemia than the controls (the SMRs were 123 and 34 respectively). Over the whole period of follow-up the participants still had a higher mortality from leukaemia than the controls, however the difference was less marked and only marginally significant (the SMRs were 100 and 56 respectively). 273. It was concluded that the significantly higher mortality in the participants compared to the controls even over the whole period of follow up, was due not to a peculiarly high instance of leukaemia in the participants, but to a peculiarly low incidence in the controls compared to the corresponding national population. No explanation was found for the low incidence of leukaemia in the controls and it was concluded that despite a "p" value of 0.01 the low incidence was a chance finding. 274. Mortality from kidney cancer was examined only for the period ten or more years after entry to the study. Over this period, the participants had a lower mortality from kidney cancer than the controls (the SMRs were 104 and 150 respectively). Mortality in the participants was close to that expected from the corresponding national population, but mortality in the controls was somewhat higher than the corresponding national population. The number of deaths observed, however, were small (21 in the participants and 32 in the controls). Further, the results were not statistically significant (p one-sided = 0.11) and the higher mortality from kidney cancer in the controls was, therefore, concluded to be a chance finding. 275. Total numbers of incident cases of cancer were also examined. Comparison was not possible with the incidence of cancer expected from the corresponding national population, as linkage of the study records with the National Cancer Registration was incomplete. However comparison was possible between the participants and the controls. The results closely paralleled those for cancer mortalities. Total cancer incidence in the participants was almost identical to that in the controls (the incidence in the participants was 97% of the incidence in the controls). The incidence of kidney cancer was lower in the participants (79% of that in the controls) and the incidence of leukaemia was higher in the participants (345% of that in the controls for the period 2 to 25 years after entry to the study and 161% of that in the controls for the whole period of follow-up). The higher incidence of kidney cancer in the controls was not statistically significant (p one-sided = 0.17). However, the higher incidence of leukaemia in the participants was statistically significant (2 to 25 years after entry to the study, p one-sided 0.001 and for the whole period, p one-sided = 0.05). 276. Finally, the participants were examined by sub-group according to the operations in which they participated, whether they had been identified by the Ministry of Defence as having been "liable to exposure to radiation, and whether they had a recorded gamma radiation dose. The examination showed that no sub-group had experienced a total cancer mortality more than ten years after exposure greater than that expected by reference to the corresponding national population. In particular, the 1,548 men who participated in the Antler series of explosions experienced a mortality rate from cancer other than leukaemia ten or more years after first participation, that was lower than the national average (SMR 88 based on 58 deaths) and 1 death from leukaemia against 2.21 expected. Furthermore, examination of the incidence of cancer in relation to the dose received among men who had been monitored for dose, provided no evidence of any increase with dose for either leukaemia or other cancers. This was what was expected in view of the small dose that the men had collectively received. 277. Sir Richard also gave evidence on a similar study commissioned by the New Zealand Ministry of Defence. That study was undertaken by the Department of Community Health of the Wellington Medical School. All together 528 personnel of the Royal New Zealand Navy were identified as having participated in UK atmospheric tests of nuclear weapons when serving on two ships. 1,504 other men who had served over the same period on three other ships that had not participated in the tests were chosen as controls. The characteristics of the men in each of the groups were broadly similar in regard to rank, age, year of enlistment and smoking habits. The men were followed from the date of first participation in 1957-58, or from 15 May 1957 in the case of the controls, until the end of 1987. Deaths and diagnosis of cancer were obtained from national mortality and cancer registration records and mortality and cancer incidence rates were compared with those expected from corresponding national rates for all men of the same ages over the same period. 278. The participants were found to have had a higher mortality from all causes and all cancers than the controls (the respective SMRs were 119 and 180 for the participants, and 106 and 130 for the controls). Mortality in the participants from all cancers was significantly higher than that expected from corresponding national rates. 279. Twenty different types or categories of cancer were also separately examined. The participants were found to have a significantly higher mortality from leukaemia than the controls (the SMRs were 702 and 126 respectively). The participants were also found to have higher mortality from kidney cancer than the controls (the SMRs were 500 and 273 respectively). However, these statistics were based on a very small number of deaths (4 and 2 from leukaemia and 2 and 3 from kidney cancer in the participant group and control group respectively). For this reason the results were not regarded as statistically significant. Furthermore, one of the 4 deaths from leukaemia in the participants was of a type that has not been associated with irradiation and the other 3 occurred more than 25 years after the tests, when the risk of radiation induced leukaemia would be expected to be low. 280. A comparison of incidences of cancer from cancer registration data revealed a slightly higher incidence of cancer in the participants than the controls (the standardised incidence rates were 131 and 116 respectively). 281. Sir Richard reported that no comparable study of Australian participants had been carried out, but that there had been two smaller investigations conducted. In the first, questionnaires were sent to individuals thought likely to have participated in the UK tests. By the questionnaire it was hoped to find out whether any particular type of illness could be associated with any particular type of involvement in the test. From 2,440 responses, the only statistically significant positive associations that were observed for any types of cancer were between the decontamination of personnel, equipment, vehicles or aircraft and the occurrence of melanoma, and between the maintenance of contaminated equipment and non-melanomatous skin cancer. In neither case was it concluded that the association was causal. (Donovan, JW., Stevenson, CE., Ariotti, DE., "Survey of Health of Former Atomic Test Personnel", Health of Atomic Test Personnel, 1983, Australian Government Publishing Service, Canberra.) 282. The second investigation traced 1,560 death certificates of personnel who had been identified as participating in the test program. These death certificates were compared with those of 3,010 control men of similar ages whose deaths had been registered in the same registries at the same time. A comparison of the proportions of deaths due to different causes showed that the proportion attributable to cancer was slightly higher in the participants (risk ratio 1.10). The excess was, however, almost entirely accounted for by an excess of lung cancer in the test participants other than members of the armed services. As this group also had a higher proportion of deaths attributed to chronic obstructive airways disease, which like lung cancer is predominantly caused by smoking, it was concluded that the excess lung cancer was unlikely to have been due to participation in the tests. The proportions of deaths from leukaemia, malignant melanomas, and other skin cancers were all lower in the participants than in the controls. No separate figure was given for kidney cancer. 283. The study concluded that there was no excess mortality which might have been due to exposure to ionising radiations. (Donovan, JW., " Causes of Death of Former Atomic Test Personnel", Health of Atomic Test Personnel, 1983, Australian Government Publishing Service, Canberra.) 284. On the basis of these studies, Sir Richard expressed the opinion that participation in the UK tests did not expose the participants to any risk of cancer, except possibly to a risk of leukaemia. Although the small New Zealand study suggested the possibility that total cancer mortality amongst participants was increased in comparison with national rates, the much larger British study provided no such suggestion. In that study the cancer mortality in the participants was significantly less than expected in comparison to national rates and practically identical with that in the control group. Moreover, none of the sub-groups that were most likely to have received any radiation showed any increased mortality. The Australian study, although epidemiologically much weaker, provided results that were consistent with either the absence of risk or the existence of a small risk, but not with the existence of a large risk. 285. The small New Zealand study also suggested that participants suffered an increased risk of kidney cancer in comparison to both the controls and the population as a whole. However, the much larger British study provided no such suggestion, the mortality rate from kidney cancer being close to normal in the participants and somewhat raised in the controls. In both the New Zealand study and the British study, the number of deaths from kidney cancer was small and the differences in mortality rates were not statistically significant. 286. In relation to leukaemia, Sir Richard concluded that although both the British and New Zealand studies provided some reason to think that participation in the tests might have caused some risk, it seems most likely that the higher mortality from leukaemia found in participants in comparison with the controls in those studies, were both chance findings. He expressed several reasons for this conclusion. First, the total mortality from leukaemia in the British participants over the whole period of the study was almost precisely what would have been expected if they had experienced the normal mortality experienced by men of the same ages in the country as a whole. Secondly, the high relative risk of mortality from leukaemia in the participants compared to the controls in the period 2 to 25 years after entry to the study was principally due to a significantly low incidence in the controls, something that was not characteristic of the controls over the rest of the period of the follow-up. Thirdly, the highest relative mortality in the participants compared to national rates was in men who were not in any of the groups most likely to have had any material exposure. Fourthly, it is difficult to attribute the excess in the Royal New Zealand Navy men to participation in the tests as (i) there is no reason to think that the men could have had any material exposure, (ii) 1 of the 4 cases was of chronic lymphatic leukaemia which has not been produced by radiation in other situations, and (iii) 3 of the 4 cases occurred more than 25 years after the tests, which would be unlikely if they had been caused by radiation at the time of the tests. 287. Sir Richard was cross-examined in relation to the evidence he gave with respect to the UK study. He was particularly questioned as to the reliability of the information provided by the Ministry of Defence. Sir Richard agreed that identification of all participants so many years after the event was not easy and the research team had to consider the possibility that the list provided by the Ministry of Defence may have been incomplete. As a result, the research team carried out many checks on Ministry records to ensure that the information was as complete and accurate as possible. Information about test participants was also sought from all other organisations known to have compiled independent lists. In the event, 412 participants were reported to the National Radiological Protection Board who had not previously been identified by the Ministry of Defence. These men were separately studied and were found to have had almost the same risk of death from cancer as the other participants. None of those men died of leukaemia. 288. Sir Richard was further cross-examined about his conclusion that the statistically significant difference in the mortality from leukaemia experienced by the participants in comparison to the controls for the period 2 to 25 years after entry to the study, was in fact a chance finding. Sir Richard justified his conclusion by pointing to the fact that when the study was continued for a further 7 years the controls experienced 11 deaths from leukaemia, which was almost exactly the same as expected from national rates. In comparison, the participant group experienced only 6 deaths from leukaemia. Therefore, over the whole period of the study the total mortality experienced by the participants was almost exactly what was expected in comparison to national rates. The mortality experienced by the controls was still lower than that expected from national rates, but the difference over the whole period of the study in comparison to the period 2 to 25 years after entry to the study was far less marked. Further, over the whole period of the study, the difference in mortality from leukaemia experienced by the participants in comparison to the controls was only marginally significant. 289. Sir Richard was also pressed as to whether the UK participants who had died of leukaemia had suffered from any particular exposure. He indicated that the high number of mortalities from leukaemia in the participant group compared to the control group over the period 2 to 25 years after entry into the study, prompted inquiries as to whether the participants who had died of leukaemia had suffered from any particular exposure. 290. Information as to the particular tasks engaged in by the participants who had died from leukaemia was supplied by the Ministry of Defence. The information indicated that the subjects had participated in a variety of tasks ranging from office clerks to sappers and signals people. The only information available about the particular exposures of those people were the exposures that had been recorded on their film badges and dosimeter records. For the purposes of the study it was also assumed that people who had taken part in the Maralinga experimental programs could have had some exposure to alpha particles which would not have been measured by their film badges or dosimeters. 291. In the end, the research team was unable to identify a group in relation to activities or exposure where there could be said to have been some excess hazard. It was found that the excess of leukaemias were in no way associated with the Maralinga program and, in fact, the excess of leukaemias seemed to be most associated with people who had not received any particular specified exposure. The participants who had been identified by the Ministry of Defence as liable to exposure to radiation, both external and internal, when studied, were found to have experienced a lower mortality from leukaemia than other groups as well as a lower mortality from other neoplasms. The group of participants that experienced mortality from leukaemia had not participated in any of the major operations, were not classified by the Ministry of Defence as liable from exposure to radiation and had not taken part in the minor trials at Maralinga. 292. No doubt, a survey which focussed specifically on, for instance, personnel who had been involved in the sweeping-up operation at Taranaki, in conjunction with some appropriate control group, might have been more immediately relevant. Unfortunately, Professor Doll was not provided with information of such specificity as to enable him to select out such a group for particular study. It is possible, of course, that such a group would have been too small a population to found a basis for reliable results. Moreover, in light of the health physics and medical evidence in the case it is, in my view, highly unlikely that such a survey would have revealed anything of statistical significance. 293. Sir Richard also referred to the results of some other tests in the following paragraph of his report, tendered in evidence:- "Non-significant increases in kidney cancer have been reported in patients treated with a short-lived isotope of radium (224 Ra) (Spiess et al., 1989) and in men who were monitored for plutonium at the Atomic Weapons Establishment in Britain (Beral et al., 1988). In both cases the numbers were small (5 against about 2.5 expected in the first and 3 against 1.25 expected in the second) and the dose in the patients treated with radium was large (46 Sv to the kidney spread out over months). No excess was, however, seen in the combined data for 11 groups of underground miners exposed to large amounts of radon (SMR 10 or more years after first employment 91, based on 41 deaths) (Darby et al., 1994b) and there is no suggestion of a hazard of kidney cancer among the few men known to have been specifically exposed to substantial doses of plutonium, neither in the men employed at Rocky flats, 17 of whom have died of cancer (Wilkinson et al., 1987) nor in the 26 men who were heavily exposed at Los Alamos when working on the manufacture of the first nuclear weapons during the second world war (Voelz and Lawrence, 1991)." 294. Sir Richard also gave evidence as to an ongoing study in which he had been involved for some time. This related to the effect of radiation by x-rays, given as treatment to a number of patients suffering from ankylosing spondylitis. He indicated that the level of exposure was very high being 6 gray and that the kidneys, being on each side of the part of the spine which was most heavily irradiated in the treatment, were amongst the organs which received the highest dose of radiation. The high dose was accumulated as a result of treatment given over several weeks. This study involved 15,000 people treated by radiotherapy for this disease. It was possible to obtain precise measures of the radiation dose that each had received. Thirty-five developed kidney cancer. The doses were very large, the mean average dose being, as indicated, 6 gray. The Professor said "we found that the best estimate of risk in relation to this was that there was a 10% increase in the relative risk of developing cancer of the kidney for each gray of radiation". This was a small absolute excess related to very high levels of dose. 295. The findings were compatible with those from Hiroshima and Nagasaki. Other studies, such as one where patients in Germany had been treated for a rare disease by the injection of radium directly into their bloodstream, also indicated that any resulting kidney cancer was in relation to a very high, even enormously high, dose. Such cases are clearly in major contrast to any conceivable radiation dose that Cubillo could have received to his kidneys as a result of work at Maralinga. 296. Another major study should be referred to. This is the Life Span Study, which I have mentioned. Evidence in relation to this study was given by Professor William Jackson Schull who has been intimately involved in it since its inception. Some reference to his curriculum vitae is, accordingly, appropriate. 297. Professor Schull was awarded the degrees of Bachelor of Science and Master of Science from Marquette University, Milwaukee, Wisconsin in 1946 and 1947 respectively. In 1949 he was awarded the degree of Doctor of Philosophy from Ohio State University. 298. Professor Schull has spent much of his career studying the effects of radiation. His professional appointments in the area have been numerous and, amongst others, have included the positions of consultant to the United National Scientific Committee on the Effects of Atomic Radiation, member of the National Council on Radiation Protection and Measurements and member of Committee 1 of the International Commission on Radiation Protection, a committee which focuses on the biological effects of ionising radiation. 299. Throughout his career Professor Schull has been intimately involved with the Life Span Study of the survivors of the atomic bombing of Hiroshima and Nagasaki in August 1945. He accepted his first research position with the Atomic Bomb Casualty Commission in Japan soon after his graduation and since then he has served as Head of the Department of Genetics of the Commission, Vice Chairman and Chief of the Department of Epidemiology and Statistics of the Radiation Effects Research Foundation and Permanent Director of the Foundation with oversight responsibilities for Epidemiology, Statistics and the Tumour and Tissue Registries. He continues to serve at the Foundation as a Senior Scientific Consultant. 300. Professor Schull is also a member of several professional organisations including the American Epidemiological Society, the American Society of Human Genetics, the Radiation Research Society and the Society for Epidemiological Research. He has been awarded several awards and professional distinctions including the Order of the Sacred Treasure Third Class Emperor of Japan, which he was awarded in 1992 in recognition of his involvement in studies of the atomic bomb survivors. 301. He is currently Director of the Human Genetics Centre of the School of Public Health at the University of Texas Health Science Centre in Houston, and Professor of Academic Medicine. He is also currently an honorary member of the National Council on Radiation Protection and Measurements in the United States, a member of the Advisory Board to the Bureau of Radiation Effects Research and Chairman of the Bureau's Committee on an Assessment of the US Centre for Disease Control and Prevention's Radiation Studies. He also serves on two US National Academy of Science National Research Council Committees involved in the assessment of the biological hazards of exposure to ionising radiation. 302. The study of cancer among the atomic bomb survivors is the largest epidemiological study ever carried out. The study has continued for over 48 years and is still continuing. Most of what is known about the biological consequences of human exposure to ionising radiation stems from this study, and current regulatory standards rest largely on the experiences of these survivors. 303. The study population consists of approximately 121,000 individuals of whom approximately 91,000 were present in the cities at the time of the bombings. The remaining 30,000 individuals were not present in the city at the time of the bombings, but roughly half of them were exposed to some degree of ionising radiation because they began entering the city within hours after the bombing on rescue operations. 304. The study has focussed on estimating the dose of ionising radiation received by each survivor and correlating this with information about incidences of cancer diagnosed amongst the survivors, in order to calculate risk estimates of developing cancer at varying levels of exposure. 305. Estimating the dose of ionising radiation received by each survivor involved interviewing each individual identified as being present within a 1,800 metre radius of the hypocentre in order to determine their age and gender, where they were at the time of exposure, that is, whether they were inside or outside and, if inside, the composition of the structure of the building they were in, the room in which they were located at the time of exposure, whether they were standing, kneeling or supine, whether they were facing towards or away from the hypocentre, what they were wearing and whether they experienced any symptoms of radiation sickness at the time. 306. This information was then used to estimate the dose received by each individual by taking into account how many structures, such as walls, ceilings and tiled roofs, shielded the individual from the hypocentre and to what extent the composition of the structures prevented the radiation from penetrating inside the building. The posture of the individual at the time of exposure and the direction in which the individual was facing were taken into account in estimating the doses of radiation to individual organs. Currently, estimates on doses to 15 organs are available for 86,632 of the approximately 91,000 exposed individuals in the study population. 307. The incidences of cancer amongst the survivors has been ascertained from three sources. First, approximately 20% of the study population are physically examined at the facilities of the Radiation Effects Research Foundation every second year. Second, copies of death certificates are obtained for each individual in the study population who has died, whatever the cause of death. Third, Tumour and Tissue Registries record information about all tumours diagnosed in Hiroshima or Nagasaki, including the identity of the individual, the type of tumour, its method of diagnosis, whether the tumour is a primary or a metastatic one, and the types of cells involved. 308. In terms of kidney cancer, the experiences of the atomic bomb survivors have enabled the research team to estimate both mortality and morbidity risks. The excess relative risk of mortality from kidney cancer has been calculated to be 0.58 per gray of absorbed dose to the kidney (90% confidence interval -0.09 to 1.94). The excess absolute risk has been calculated to be 0.09 (90% confidence interval 0.02 to 0.26). It has been concluded by the research team that neither of these risk estimates for cancer of the kidney is statistically significantly different from 0 (zero), that is, they show no increased risk. 309. The excess relative risk of developing cancer of the kidney per sievert of dose to the kidney has been calculated to be 0.71 (95% confidence interval -0.11 to 2.25). The corresponding excess absolute risk has been calculated to be 0.29 (95% confidence interval -0.50 to 0.79). From these calculations the researchers have concluded that there is no statistically significant increase in cancers of the kidney with increasing dose, although they concede that the data, when taken at face value, does suggest some small increased risk might exist. 310. Professor Schull gave evidence that in his expert opinion these two sets of data fail to demonstrate a statistically significant increase in the occurrence of cancer of the kidney following exposure to ionising radiation. 311. Applying the risk estimates to the dose to the kidney of 0.002 rem calculated by Mr Davy to have been received by Mr Cubillo, Professor Schull estimated that Cubillo's risk of developing kidney cancer was increased by approximately 5.8 x 10 -6. He expressed the opinion that this was a very small increase in risk. Further, he stated that Cubillo's true risk would be even smaller because this risk estimate calculation covers the risk of developing any form of kidney cancer, not just specifically a renal cell carcinoma. Further it does not take into account that the risk of developing kidney cancer has been found to be higher in females than males. Professor Schull concluded that it was most unlikely that any ionising radiation Cubillo may have been exposed to at Maralinga caused or contributed to his renal cell carcinoma. 312. In cross-examination, counsel for the applicant put to Professor Schull that if Cubillo was unfortunate enough to ingest radioactive material in the process of wiping a contaminated glove across his face and mouth, he might receive a high enough dose of ionising radiation to cause or contribute to a cancer of the kidney. Professor Schull rejected this proposition on the basis that if a dose of radiation was ingested which was large enough to cause kidney cancer one would expect to see other effects as well, primarily skin effects. 313. Professor Schull's evidence is clearly supportive of the proposition that Cubillo could not have suffered his renal cell carcinoma as a result of exposure to radiation at Maralinga. 314. I have dealt with the evidence of these two eminent witnesses at some length because it provides two cogent examples of the weight of epidemiological material confronting the applicant's case. I mean no disrespect to the other eminent witnesses who were called by the Commonwealth in this area when I do not seek to refer in detail to their contributions to the case. 315. I have had the advantage of a comprehensive report and detailed testimony from Dr Colin Muirhead, supportive of the conclusions to be drawn from the British studies in which he played a significant role. Also from Dr Shirley Fry who supplied a comprehensive summary of significant studies in the field which led her to conclude that there was no epidemiological support for a causal connection between Cubillo's cancer and exposure to radiation at Maralinga. 316. Emeritus Professor Warren Keith Sinclair provided a report and gave oral evidence. He also had most impressive qualifications which covered the fields of mathematics, physics, physiology, biochemistry and biophysics. His main work was in the field of radiation biology but, quite clearly, he had considerable expertise in epidemiology. Before his retirement in 1991 he had been President of the National Council on Radiation Protection (NCRP) of the United States, an independent professional organisation of great repute which evaluates radiation risks and makes reports on them to government. 317. At the international level he is a member of the International Commission on Radiological Protection (ICRP) and Chairman of its Committee on Biological Effects. This body provides recommendations on radiation safety standards and procedures at an international level. He is also a delegate for the United States to the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) and has also served as a consultant to that body. He has also served and serves upon other bodies of international importance in the radiation field. 318. Professor Sinclair provided information on a number of the topics which have been considered in the case and was in general agreement with the conclusions of Professor Doll and the other witnesses called by the respondent. His conclusions were opposed to those of Dr Kefford. 319. He explained at some length a methodology, the validity of which was not questioned, and which was named the "Probability of Causation Approach". This applied sophisticated mathematical and statistical analysis to data to arrive at a degree of likelihood that a particular event was caused by a particular agent. He applied this approach to the question of the causation of Cubillo's cancer through inhalation or ingestion of plutonium 239 at Maralinga. I need say no more than that the result of his calculations was that the likelihood of such causation could be described as negligible. 320. The evidence given by these experts quite clearly, in my view, supports the conclusion I had already reached on the evidence from the health physics and medical fields. I am satisfied, on the whole of the evidence, that Cubillo's renal cell carcinoma was not caused by exposure to ionising radiation at Maralinga acting either directly or synergistically. 321. Before parting with this case, however, I should make some observations and findings on the question of negligence. NEGLIGENCE 322. Earlier in these reasons I referred to the acts and omissions relied upon by the applicant. The first four related to allowing the applicant to be in areas where he was at risk from inhalation or ingestion of alpha emitters, specifically plutonium 239. In fact, the first three related to his being allowed to eat in such areas without any appropriate warning. On the findings I have made, these grounds need not be considered further. I am satisfied that he did not eat in such areas. 323. Similarly, neither is ground (iv) made out. I am not satisfied that Cubillo was subject to the supervision, direction and control of Lance Corporal Hutton in any areas where there was risk from inhalation or ingestion of plutonium 239. 324. Grounds (v), (vi) and (vii) relate to supervision and warning of the applicant in relation to the wearing of respirators. Grounds (v) and (vi) relate to the Taranaki sweep-up. Ground (vii) is in general terms. In view of the findings I have made, these grounds must be restricted to the Taranaki sweep-up. As I have found, that operation was conducted in a professional manner without any breach of standards of care appropriate at the time. The applicant was provided with a respirator. It would have been quite clear, even in the absence of very specific warning, that it should not be removed whilst work was being conducted in dusty conditions in a "yellow" controlled area. As I have found, I am satisfied that health physics personnel were in the area whilst the work was being conducted. Clearly, it would not have been possible for each engineer to be personally observed and supervised. It was reasonable, in my view, for the respondent to rely upon the engineers not removing their respirators in dangerous conditions. In any event, the relevant danger was from the alpha emitter plutonium 239. The evidence of Mr Davy, which I have accepted, effectively removes this as a risk for consideration. 325. Ground (viii) adds nothing to what has gone before and may be disregarded. 326. Consequently, irrespective of the finding on causation, I am not satisfied that any of the respondent's acts and omissions specifically relied upon have been established. 327. Finally, as indicated earlier, the applicant sought to make out a case by reliance upon the principal underlying the decisions in cases such as Birkholz; McGhee; Bonnington Castings v Wardlaw (1956) AC 613; The State of Western Australia v Watson (1988) Aust Tort Rep 80-266; and Bennett v Minister of Community Welfare (1992) 176 CLR 408. 328. Counsel for the applicant placed particular reliance on the following passages:- "Where a defendant is under a legal duty to take precautions to protect the plaintiff from the risk of contracting disease, and, by omitting those precautions he substantially increases the risk of the plaintiff contracting that disease, the law treats that increase in risk as a sufficient basis, in the absence of evidence showing how the infection occurred, for an inference that the omission of the precautions materially contributed to the contracting of the disease." (per King CJ in Birkholz v R J Gilbertson Pty Limited 38 SASR 121 at 130); "What is a material contribution must be a question of degree. A contribution which comes within the exception de minimis non curat lex is not material, but I think any contribution which does not fall within that exception must be material. I do not see how there can be something too large to come within the de minimis principle but yet too small to be material." (per Lord Reid in Bonnington Castings v Wardlaw (1956) AC 613 at 621). 329. It was counsel's submission that the Commonwealth had breached its legal duty to protect Cubillo from the risk of injury from radiation. This breach of duty resulted in a substantial increase in the risk of Cubillo's developing renal cell carcinoma. In the absence of evidence as to the exact cause of that carcinoma the substantial increasing of the risk was a sufficient basis for an inference that the Commonwealth's breach of duty had materially contributed to it, unless the Commonwealth could show that that contribution fell within the exception de minimis non curat lex. 330. It must be observed at the outset of consideration of this submission, that the principal relied upon does not obviate the necessity of an applicant establishing a breach of duty. It is only of assistance in establishing causation once that breach has been proved. As I have already held that no breach has been established, the occasion for the application of these cases does not arise. However, lest it be considered that they can have some application in subverting the finding on causation which I have already made, I deem it desirable to give this submission some further consideration. 331. Birkholz, McGhee, Bonnington and Watson were all cases in which the plaintiff's disease or condition could only have been caused by one agent, namely contact with infected cattle, brick dust, silica dust and asbestos dust respectively. It was established in each case that the plaintiff had come into contact with these dangerous agents in the course of his employment, it being admitted or proved that the employer had failed in its duty to take adequate precautions to protect the plaintiff from injury of the kind the plaintiff subsequently suffered. 332. In Birkholz, the plaintiff was suffering from brucellosis and it was accepted on the evidence that the plaintiff's disease was caused by contact with infected cattle which could have occurred in one of a number of possible ways, the precise way being impossible to identify. Only some of the possible ways in which contact may have occurred could have been prevented by reasonable precautions on the part of the employer. The question in issue was, therefore, whether in the absence of proof as to the precise way in which the plaintiff came into contact with the infected cattle, the employer's breach of duty could be held to have caused or materially contributed to the plaintiff's brucellosis. 333. In Bonnington, it was accepted on the evidence that the plaintiff's disease was caused by accumulated contact with silica dust in the course of employment. It was established that the plaintiff had come into contact with the silica dust both as a result of the employer's breach of duty and in circumstances in the course of employment which involved no breach of duty. The question in issue was whether exposure to the causal agent occasioned by the employer's breach of duty could be said to have caused or materially contributed to the plaintiff's disease. Although the facts of McGhee were slightly different to Bonnington, like Bonnington it also concerned causation of a disease by cumulative causes and the question in issue was substantially the same. The same may be said of Watson. 334. Each of these cases can be distinguished from the present case. Even if it had been proved on the balance of probabilities, first, that the Commonwealth had breached its duty of care to protect Cubillo from the risk of injury from radiation, and second, that Cubillo had been exposed to radiation as a result of the breach, this would not be a case in which the cause of the disease could be attributed to only one agent, namely, exposure to radiation. As a result, the facts of the case do not give rise to either of the issues which concerned Birkholz, McGhee, Bonnington or Watson and do not allow the question of causation to be decided as in those cases. Furthermore, any exposure to radiation must, for the purposes of this case, be confined to radiation from the alpha emitter plutonium 239. It could not be said, on any basis, that that exposure substantially increased the relevant risk. 335. It should also be noted that the House of Lords in Wilsher v Essex Area Health Authority (1988) 2 WLR 557 considered whether McGhee established any new approach to the law of causation. It was held that it did not. Lord Bridge of Harwich (at 569) stated:- "...McGhee v National Coal Board laid down no new principle of law whatever. On the contrary, it affirmed the principle that the onus of proving causation lies on the pursuer or plaintiff. Adopting a robust and pragmatic approach to the undisputed primary facts of the case, the majority concluded that it was a legitimate inference of fact that the defendant's negligence had materially contributed to the pursuer's injury. The decision, in my opinion, is of no greater significance than that and to attempt to extract from it some esoteric principle which in some way modifies, as a matter of law, the nature of the burden of proof of causation which a plaintiff or pursuer must discharge once he has established a relevant breach of duty is a fruitless one." (See also Bennett at 416). 336. In the result, I am of the opinion that the applicant's case fails. I accordingly dismiss the application. The applicant was legally aided. In these circumstances I have been asked to reserve the question of costs. I accordingly do so. 337. I therefore order that:- 1. The application be dismissed; 2. Costs be reserved.