The AWRE formed a small decontamination and health physics team in the UK and shipped them to Maralinga to work with range staff on Hercules 5, under the supervision of Pearce, who was on site for the last three weeks of the operation. There was only one Hercules operation. Pearce said the name Hercules 5 was ‘dreamed up by one of the staff because the fifth labour of Hercules was to clear out the Augean stables’. In classical mythology, this labour was, tellingly, considered to be both humiliating and impossible. Counsel assisting the Royal Commission, Peter McClellan, mused aloud that perhaps the AWRE saw this part of Australia as Augean stables. Pearce kept his answer neutral and non-committal. But there was a heaviness in the atmosphere during Pearce’s testimony in London. The Royal Commission was in the UK capital to question the people responsible for radioactive contamination of Australian territory. Pearce’s name was inextricably linked to this dreadful aftermath.
The Hercules 5 clean-up plan was presented to the AWTSC in 1964 and passed with few amendments. The Royal Commission later dwelt on the fact that the clean-up and survey phases were rushed through, noting how the AWTSC had enthusiastically rubber-stamped the plan and no-one had stopped to think that one day Indigenous people might want to come back to the lands from which they had been so brutally expelled. Also, while approval was given for cleaning up within the boundaries of the range, no plans were drawn up for surveying and clearing up any contamination that had fallen outside the boundaries, other than at Emu.
During his grilling at the Royal Commission, Pearce constantly put the responsibility back on the AWTSC, minimising his own input in the management of the clean-ups and survey. He made it clear that he had not thought much about the plight of the Aboriginal people, and it had not informed his approach to his task. The problem was that the AWTSC did not want to manage the clean-up either. No-one wanted to own the responsibility for a dying weapons range. Both the AWRE and the AWTSC thought the Maralinga era was over and would soon be forgotten. The AWTSC explicitly stated in its liaison with Pearce, as revealed in testimony to the Royal Commission, that once the range had been tidied up it should be patrolled for about 15 to 20 years. After that time, the public would no longer be interested in it. When the Royal Commission raised this time frame with Pearce, he did not see anything particularly cynical about it, though he pointed out, a little ruefully, that interest had not in fact disappeared after all. On the contrary.
Hercules 5 was not based on a physical survey of the site but on existing records. That meant making a number of lazy assumptions rather than plotting the real radiation risks on the ground. The task set for the Hercules team had 10 parts to it, encompassing cleaning contaminated buildings and vehicles, burying any contaminated materials that could not be cleaned in pits at Taranaki, carrying out a health physics survey of the area to determine the risk to human health of any contamination, fencing any areas that still had residual contamination and preparing drawings to show where the fences and pits were located.
Hercules lasted from August to November 1964 and produced two reports, one describing the radiological state of the range at the conclusion of the clean-up and the other prepared especially for the AWTSC describing the residual radioactive and toxic contamination still present. Pearce stated at the end of the operation that the signs and fences would be regularly inspected and maintained, but that the range was now more or less in a holding pattern, pending a decision on its future. He recognised that Hercules was not a final clean-up but thought it would do until longer term decisions were made and personnel departed the site.
Pearce well knew that plutonium was loose on parts of the range and, with his team, calculated the inhalation hazards from the plutonium mixed with the dust. The inhalation hazards drove much of the clean-ups. He also recommended, based in part on data provided by Harry Turner, that the topsoil could at some point be ploughed to dilute the plutonium by mixing it through the soil to a greater depth than where it currently lay. This proposal was put to the AWTSC, which agreed that diluting the plutonium was wise. Ploughing and grading were duly carried out around Wewak, TM100 and TM101, as part of Hercules. The contents of various contaminated refuse pits around the site were consolidated into a total of 19 huge burial pits at Taranaki. The pit area was enclosed in a high chain-link fence. Ploughing was not, however, such a great idea. As radiation scientist Geoff Williams later said about ploughing the plutonium into the topsoiclass="underline"
That might have sounded very nice in the lush fields of southern England but out there [at Maralinga] you have three or four inches of sand on top of very hard limestone, so in many cases the scraper was just bumping along on the limestone. If it had solved the problem, if it had really diluted to a sufficient level, it would have been all right. But it didn’t because the fragments and the concentration were so high, all it did was make a bigger mess.
No measurements were made of the effectiveness (or, indeed, otherwise) of ploughing the plutonium into the soil. As Pearce said in evidence, ‘We knew the levels of activity on the surface and it was reasoned that if that were distributed uniformly through a thickness you would finish up with a uniformly contaminated layer of soil some inches or 15 cm thick… I cannot recall any experimental evidence for that at the moment’. Hercules was conducted without any form of testing on either side of it. It was mostly guesswork.
The original 10-year agreement for the British to use Maralinga was due to expire on 7 March 1966. This forced a decision, because maintaining the site was costly and pointless unless it was going to be used for further tests. On 16 February 1966, four weeks after Menzies retired from office, the Australian Government received word from the UK High Commission that Britain would relinquish the site. The Maralinga agreement meant that they needed to clean it up. Remarkably, the AWRE – in possession of so much knowledge about what was left there – proposed four completely inadequate actions to make the site safe, starting with disc-harrowing some open areas of ground ‘with a view to reducing the hazard to a level safe for permanent human habitation’. The other three measures were sealing the pits with concrete and sand, removing from Maralinga village a small amount of radioactive ducting material and sealing drains. Disc-harrowing – churning up the topsoil using a tractor towing large circular blades – could never make the area safe for people to live in. At the Royal Commission many years later, John Moroney gave evidence that even the notoriously lax AWTSC never took this suggestion seriously. He said that the only way that the site could be made habitable was by removing all the plutonium, not by churning it into the sandy topsoil. At this point, Jim McClelland berated Moroney, and the safety committee, for not just recommending that all the plutonium be removed, instead of mucking around with ploughing and disc-harrowing. Moroney replied, ruefully, ‘It would have been a good idea, yes. We would not have had this Royal Commission’.
Pearce did not spend a lot of time physically at Maralinga, although he visited at crucial moments. In early 1966 he arrived at the test range with his AWRE boss Roy Pilgrim to survey the site. At that time they decided to set up RADSUR to survey Emu Field and Maralinga so they could produce the appropriate documentation needed to meet the requirements of British withdrawal. They made no such plans for Monte Bello, which was essentially ignored until much later. RADSUR was a flawed attempt to map radio-active contamination before Operation Brumby.