Dig for secrets: the lesson of Maralinga's Vixen B

Liz Tynan

Chain Reaction #119, Nov 2013, www.foe.org.au/chain-reaction/editions/119

Occasionally I give guest lectures to undergraduates about Maralinga. In the vast majority of cases, the students have never heard of the place. A small number may have heard the word, but don't know what it means. Most have never heard it at all.

This lack of knowledge about the British nuclear tests in Australia is not surprising. The tests were not part of the national conversation for many years. Although older people remember something about the test series, no-one knows the story of the most secret tests of all, the ones that left the most contamination: Vixen B.

Maralinga is a particularly striking example of what can happen when media are unable to report government activities comprehensively. The media have a responsibility to deal with complex scientific and technological issues that governments may be trying to hide. While Maralinga was an example of extreme secrecy, the same kind of secrecy could at any time be enacted again. The Edward Snowden case has shown what can happen when journalists become complicit in government secrecy, and we have learned the press must be more rigorous in challenging cover-ups. That did not happen during the Maralinga era.

The British nuclear test program was spread over 11 years, from 1952 to 1963, and took place at three locations: the Monte Bello Islands off the coast of Western Australia, and Emu Field and Maralinga in the South Australian desert. A total of 12 "mushroom cloud" bombs were exploded: three at Monte Bello, two at Emu Field and seven at Maralinga.

Vixen B

The tests that had more far reaching significance than the 12 major trials, however, were the 12 radiological experiments known as Vixen B that were only held at Maralinga. These experiments used TNT to blow up simulated nuclear warheads containing a long-lasting form of plutonium.

In total, Vixen B scattered 22.2 kg of plutonium-239 around the Maralinga test site known as Taranaki, with some 20kg initially thought to be in the adjacent burial pits and over 2kg dispersed across the test range. Later it was found that rather than the 20kg sitting safely in the 21 Taranaki burial pits that were bulldozed at the time to hold waste material, it was actually spread around the site in particles of widely divergent size.

This form of plutonium has a half-life of over 24,000 years. The extreme persistence of radiation and the threat of cancer posed by inhaling small particles in dust at the site make this substance especially dangerous.

The toxic legacy of Maralinga can almost entirely be summed up in one word: plutonium. When the Maralinga Rehabilitation Technical Advisory Committee (MARTAC) reported in 2002 on the outcome of the operation to remove contamination from the area, co-funded by the British government, it said "Plutonium ... was almost entirely the contaminant that determined the scope of the [Maralinga rehabilitation] program." The site was rehabilitated in the mid to late 1990s, with some UK government funding, although controversies continue about the effectiveness of that remediation.

While the major trials sent clouds of minute particles of debris into the stratosphere (more than 10km above the ground) and spread fallout over most of the continent, the impact of the minor trials was more concentrated, more geographically contained and longer-lasting.

Plutonium oxide from Vixen B shot up between 800 and 1,000 metres into the air, where it was picked up by the wind and carried in plumes that spread northwards from the firing pads in a pattern about 150 kilometres long and many metres wide.

The 1968 Pearce report, prepared by the British physicist Noah Pearce, claimed that the 1967 clean-up operation had placed about 20kg of the 22kg of plutonium into 21 shallow pits adjacent to the Taranaki firing range. In fact, most of the plutonium was later found to be scattered around the site.

MARTAC confirmed that the plutonium contamination at Taranaki, as described by the Pearce report, was wrong by a factor of 10: "A comparison between the levels reported by the UK at the time (Pearce 1968) and the field results reported by the Australian Radiation Laboratory ... (Lokan 1985) demonstrates an underestimate of the plutonium contamination by about an order of magnitude."

The errors perpetuated by the Pearce report resulted in considerable confusion and misinformation about plutonium contamination at Maralinga for many years.

Royal Commission

Most people who know anything at all about the British tests usually know that Robert Menzies did not consult Cabinet when he agreed to the first British test, at Monte Bello in 1952. Later, the Australian judge and former federal Labor politician who was to lead the 1984-1985 Royal Commission into the British nuclear tests, Jim McClelland, described Menzies' actions as both "grovelling" and "insouciant". The McClelland Royal Commission came to be described as a spectacle of national revenge.

The output of the contemporary media shows a notably limited understanding of the scientific and technological aspects of the bomb tests, and their political ramifications. This era is an example of exceptionally successful media management, in which the official line presented by the test authorities and both the UK and Australian governments dominated. The 1950s media found themselves incapable of overcoming the high official stone wall.

By the late 1970s a marked change in how the Australian media covered the British nuclear tests was apparent. The Australian media had dropped its Menzies era compliance and was nurturing some resourceful investigative journalists who would not follow the official line.

Political scrutiny also stepped up. Momentum began to build around the time that the left-wing ALP politician and then deputy leader of the opposition Tom Uren asked a question of the Minister for Defence, Jim Killen, in Parliament in December 1976. This question challenged the ongoing Maralinga secrecy, particularly surrounding Vixen B.

Killen was under growing pressure to look more closely at the issue. One of the most significant outcomes was a secret Cabinet submission tabled on 11 September 1978, titled "Plutonium Buried Near Maralinga Airfield". This was not actually plutonium from the Vixen B experiments, but a significant amount of the substance in barrels of salt from an earlier experiment.

The submission raised a potential security problem: "It would not appear difficult for a small party of determined men who had received information to recover the substance in a single quick operation if they were willing to take large risks to themselves. They could then threaten, say, to exploit the extremely toxic properties of plutonium against the population of a major city."

This secret submission was to become central to the journalistic uncovering of Maralinga that set in motion years of media scrutiny of the legacy of Maralinga. The investigative journalist Brian Toohey ran a series of stories in the Australian Financial Review in October 1978, based in part on the leaked Cabinet submission.

Toohey's stories brought the wrath of Defence Minister Killen down on his head. Killen denounced Toohey in Parliament, accusing him and the Australian Financial Review of issuing an invitation to terrorists to help themselves to the dangerous material at Maralinga.

Several months before the McClelland Royal Commission began in 1984, Toohey wrote a National Times feature that provided a detailed examination of Vixen B, containing information that had, until then, not appeared publicly. Toohey wrote: "It would seem that what the British and Australian authorities described as minor experiments in fact involved the cavalier dispersal of plutonium and have created a far greater health hazard at Maralinga than the full-scale atomic tests."

The landmark New Scientist story by Ian Anderson in 1993 was the most significant later era piece of investigative science journalism on Maralinga. The story titled "Britain's dirty deeds at Maralinga" went further than ever before in uncovering the truth of Vixen B. Anderson was the first to show publicly how much plutonium contamination remained at the site and that the true level of contamination had been known by the British authorities but covered up.

What are we to make of the events at Maralinga in the 1950s and 1960s, and particularly the Vixen B tests? Australia was not a nuclear power. It was in a highly ambiguous position – it was the staging ground for nuclear weapons testing but the tests themselves were run with great secrecy and control by another nation, the "mother country" herself. This made Australia, at least initially, curiously powerless and inept in dealing with the tests.

The biggest failure of all was to completely overlook by far the most dangerous tests held at Maralinga, Vixen B. The total secrecy surrounding Vixen B was more for political rather than military or national security reasons, and the British acknowledged later that there was no reason other than political for them not to be held on UK territory. The absence of media coverage and public debate created a gap in most people's understanding of Maralinga, making it in many ways a uniquely tangled national issue, still mysterious and perplexing.

Dr Liz Tynan is a Senior Lecturer in the Graduate Research School at James Cook University, Townsville.

This is a longer version of an article published in The Conversation on 26 July 2013.