(see Graphic)
Next Thursday in London, Australian ministers will demand that Britain pay
at least A $75 million ( £33 million) to clean up land
at Maralinga in South Australia contaminated by British nuclear tests more
than thirty years ago. The Australians also want A $45 million to
compensate the Maralinga Tjarutja, the Aboriginal tribe that has been
deprived of access to about 3000 square kilometres of its land as a result
of the tests.
The meeting is expected to be heated. Recent government statements suggest
that Britain will refuse both demands. It will argue that Maralinga was
satisfactorily cleaned up after the tests finished and that, in an agreement
reached in 1968, Australia signed away the right to make claims against
Britain for mopping up.
The Australians will argue that Britain is in the wrong, both factually and
morally. ‘If they had been as far out in the design of their bomb as they
were with measuring the contamination, they would never have been able to
build the bomb in the first place,’ says Peter Burns of the Australian
Radiation Laboratory (ARL) in Melbourne.
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Burns and his colleagues now believe that contamination at Maralinga is much
worse than Britain has admitted. They say 21 pits, which were dug to hold
radioactive waste, contain far less plutonium than Britain maintains. The
remaining plutonium – ten times more than Britain has acknowledged – was
spread over the land.
SENSITIVE ISSUE
The Australians will say that if they had known the full extent of the
pollution, they would never have signed the agreement releasing Britain from
its responsibilities over the cleanup. The Australian case has been
reinforced by recently declassified American documents covering joint
British and US nuclear tests in Nevada in the early 1960s, codenamed Roller
Coaster. Since 1990 the ARL, which advises the Australian government, has
sifted through vast quantities of documents and microfiches supplied by the
US Department of Energy.
According to the ARL’s scientists, the implications of the American results
for Australia are that the plutonium would have been dispersed over greater
distances with higher concentrations on the ground. Although the British
were aware of this data as early as 1963, they never passed it on to the
Australians.
The forthcoming meeting will bring together senior ministers from the two
countries. Since September 1991, when they lodged their claim for Britain to
share the cleanup costs, the Australians have been met in Britain only by
junior ministers. Also, Australia told Britain of the technical deficiences
of its early surveys and cleanup in December 1991. Simon Crean, Australia’s
Minister for Primary Industries and Energy was annoyed by what he saw as
foot dragging. Last year he called in Britain’s High Commissioner in
Canberra to complain. In next week’s meeting, Crean and foreign minister
Gareth Evans, will be pitted against Britain’s Foreign Secretary, Douglas
Hurd, Secretary of State for Defence, Malcolm Rifkind.
The dialogue between the two nations over Maralinga dates back more than
forty years, when the world was in the grip of the Cold War. Britain wanted
to join the nuclear club. The US, the founder member of the club, was
reluctant to share its secrets. Australia offered vast remote areas in
which Britain could test its nuclear technology. And between 1952 and 1963,
Britain conducted three atomic explosions at the Monte Bello Islands off
the coast of Western Australia and nine at Maralinga and Emu, which are
located next to the Woomera rocket range, about 1000 kilometres northwest of
Adelaide.
In an effort to study the behaviour of different components of an atomic
bomb, British scientists also carried out hundreds of tests using high
explosives in combination with radioactive materials. These ‘minor’ trials,
especially the 30 that used plutonium-239, caused the worst contamination.
Twelve of these, called one-point safety trials, sent jets of molten
plutonium up to 1000 metres into the air, spreading contamination in narrow
‘plumes’ outwards from the firing pads at Taranaki.
In 1964, after the tests finished, the British mounted Operation Hercules, a
limited cleanup of the site. This was followed in 1966 by a radiological
survey and, a year later, by Operation Brumby – a major cleanup mounted by
staff from what was then called the Atomic Weapons Research Establishment
(AWRE) in Aldermaston. During the operation, the 21 pits, filled with
contaminated equipment, were capped with 650 tonnes of concrete. Also, an
area of about 2 square kilometres around the firing site was ploughed up, in
an attempt to reduce the hazard posed by surface contamination.
In a 1968 report, Noah Pearce from AWRE claimed that the operation had been
effective. He calculated that approximately 20 of the 22 kilograms of
plutonium used at Maralinga was buried in the pits. On the basis of this
study, the Australian government signed an agreement that it was satisfied
with Britain’s attempt to clean up the site. The agreement released Britain
‘from all liabilities and responsibilities’ at Maralinga.
Except for an incident in 1978, in which Britain repatriated 0.5 kilograms
of waste plutonium from a nearby site, this was how things remained until
1984, when the 3000 square kilometres of land around the test site were due
to be returned to the Aborigines. A team of scientists, including Burns,
Geoff Williams and Malcolm Cooper, all of the ARL, went to check the
radioactivity at Maralinga. The group was stunned to find levels that were
higher and spread more widely than Pearce had described. They also found the
first of many fragments of contaminated equipment. One piece of steel
contained 3 grams of plutonium.
The 1984 visit by the ARL scientists was a watershed. It sparked off a train
of events which led to a Royal Commission that was highly critical of
Britain’s role at Maralinga (This Week, 12 December 1985). In turn, this led
to the formation of a joint American, Australian and British Technical
Advisory Group (TAG), which was given the job of designing methods for
clearing up the site once and for all. Since 1984, ARL scientists have
pieced together what happened to the radioactive fallout.
‘A lot of what we did at Maralinga was nuclear archaeology,’ says Williams.
The team’s conclusion was that Pearce’s report was ‘basically flawed’. For
example, it missed the polluted fragments. The ARL scientists now estimate
that there are more than 3 million of them, ranging in size from a few tens
of micrometres in diameter to objects bigger than a cricket ball. The health
hazard posed by these fragments has never been adequately dealt with,
according to ARL. People could just pick them up.
Another ‘inadequacy’ in Pearce’s report, was a misunderstanding of how
plutonium particles in the soil were resuspended in air after being
disturbed. The amount that could be inhaled was between six and twenty times
greater than Pearce suggested, says Burns. This is important because
Aboriginal children often play in dusty conditions.
Perhaps the most significant discrepancy in the Pearce report was in the
overall levels and distribution of radioactivity. The report says that
about 2500 metres from the firing pad, radioactivity levels were less than 1
microcurie per square metre (37 000 becquerels per square metre). But the
ARL found levels up to ten times this amount. At 8 kilometres from the
firing pad, the ARL found radioactivity as high as 3 microcuries per square
metre. ‘For a nation to conduct such a technically sophisticated programme
and then get contamination levels wrong by a factor of 10 – it’s just
unbelievable,’ says Williams.
The ARL scientists admit that they had an advantage over Pearce because they
used gamma ray detectors to measure emissions from americium-241, a decay
product of plutonium-241. The British had to rely on alpha particle
emissions from plutonium which are difficult to detect. ‘But they could have
done radiochemistry analysis of the soil which would have given a more
accurate reading of plutonium,’ said Burns.
The discrepancies in radiation distribution meant the boundaries for
describing dangerous areas where plutonium pollution was high were drawn in
the wrong places. Because of this, the ARL says some of the cleaning up
during Operation Brumby, was carried out in the wrong places. One plume was
missed altogether.
The ARL’s findings of higher and more widely dispersed radioactivity were
supported by an aerial survey conducted in 1987 as part of the TAG
assessment.
In the past three years, further support has come from the US and British
tests conducted in Nevada. Some of these were similar to the one-point
safety trials in Australia. They reveal that such tests spread plutonium
more widely than Britain admitted in Australia.
Using data from the American documents, together with those from Mara-linga,
ARL scientists conclude that most of the 22 kilograms of plutonium used at
Maralinga was dispersed as an aerosol over plumes that reach out 150
kilometres or more from Taranaki. A British report, AWRE Report T4/61,
written in 1961, also suggests that plutonium was spread as an aerosol. But
it was not given to the Australians until 1985.
Next Thursday, Australia will ask Britain to pay a large proportion of the
cost for a stringent cleanup. Of the methods presented to it by the TAG
(This Week, 24 November 1990), Australia chose an option costing A Dollars
101 million. The plan is to pass an electric current through the material in
the 21 pits, turning it into a glass-like substance in order to ‘immobilise’
it. This process, called in situ vitrification, is needed because the pits
are too shallow to contain the contamination. At Marcoo, a crater from an
atomic explosion will be capped with concrete. The Aborigines will be given
back their land, except for 480 square kilometres, encompassing the
contaminated plumes. This area will be fenced off.
Last week, a spokesman for the Ministry of Defence in London refused to be
drawn on the Australian allegations. But it seems unlikely that Britain will
agree to share the cost of the cleanup. In the House of Commons on 1 April,
Archie Hamilton, the then armed forces minister, said Britain’s obligations
for decontaminating Maralinga were fully discharged in the 1960s.
He also played down the health effects of the remaining radiation, equating
dose levels at Maralinga to those in Cornwall from naturally occurring radon
gas. ‘He was being mischievous,’ said Williams. ‘It is not acceptable
internationally to compare levels of man-made radioactivity with those of a
naturally occurring radionuclide.’ Doses in Cornwall could reach 8
milli-sieverts a year. But, according to the TAG, because of the Aboriginal
lifestyle, a child living near Taranaki could inhale more than 460
millisieverts a year.
Hamilton continued: ‘We firmly believe that any question of providing
compensation for the Aboriginal population is not a matter for Her Majesty’s
government.’ The Aborigines were not moved to make way for the British
nuclear tests, he said. But Andrew Collett, a lawyer representing the
Tjarutja, says Hamilton spoke in half-truths. ‘He’s right in saying the
people weren’t moved because of the tests. But they were moved to comply
with British military interests. They were in the way of the Woomera rocket
range with which Britain was involved.’
The scene is set for a heated debate. While Britain digs in to defend its
position, Australia is on the offensive. Last month, Crean visited Maralinga
and told journalists exactly what he expected of Britain. He also knows his
demands may be refused. In this case, he warned, his next move will be to
the International Court of Justice.
