Steve Quayle News Alerts

November 24, 2003
By Mark Dunn

ALMOST 18kg (40 pounds) of uranium, including 9.7kg (21 pounds) of enriched uranium, was unable to be accounted for at the Lucas Heights nuclear reactor.

The whereabouts of 62kg (137 pounds) of radioactive thorium also remained a mystery after audits at the high-security Australian Nuclear Science and Technology Organisation failed to pinpoint the material.

Australia's nuclear watchdog, the Australian Safeguards and Non-proliferation Office, has identified unaccounted-for batches of nuclear material on seven occasions during inspections at the reactor since 2000.

ASNO categorizes the problem as MUF (material unaccounted for), and found:

* IN 2002-2003, 3.37kg (7.5 pounds) of natural uranium, 0.01kg (.02 pounds) of depleted uranium and 1.01kg of thorium was unable to be accounted for.
* IN 2001-2002, 9.7kg (21 pounds) of enriched uranium, 310g of U-235 isotope and 4.41kg of depleted uranium was unaccounted for.
* INVESTIGATORS were unable to account for 61.2kg (135 pounds) of radioactive thorium, a material used in the nuclear fuel cycle, at ANSTO in 2001.

ASNO believes most of the material is unable to be found because of faulty records or failures in accounting for substances that were transferred from waste stocks to inventory storage.

ASNO and ANSTO both said there was no evidence nuclear material had been stolen or lost at the New South Wales site.

In 2000 ASNO asked Lucas Heights to improve its controls when a 0.34kg container of powdered natural uranium was "mislaid" and other records were inaccurate.

"ANSTO has undertaken to strengthen its accountancy and control system to prevent recurrence," ASNO reported.

Although investigations are continuing into some MUF issues, ASNO assistant secretary Andrew Leask said the International Atomic Energy Agency had found ANSTO complied with reporting conditions and safeguards.

"MUF, in its various forms, it doesn't necessarily indicate anything sinister," Mr Leask said.

He said nuclear plants worldwide experienced MUF and ASNO used those instances in Australia to improve accounting controls.

In its most recent annual report, ASNO said MUF discrepancies in 2002-03 were due in part to a major transfer of waste holdings from the previous year.

It blamed the 2001-2002 MUF problem, including the 9.7kg (21 pounds) of enriched uranium, on a transfer of 500kg (1,102 pounds) of enriched uranium from waste stock back onto safeguards inventory at the request of the IAEA.

The IAEA had ruled the material, which had been accumulating since 1974, should be kept under closer scrutiny until it was fully conditioned for final disposal.

"When this was done the aggregated total was found to differ from currently available data," ASNO said.

"The material is active waste from isotope production stored in sealed tanks and so is difficult to measure accurately."

ANSTO spokesman Steven McIntosh said the 9.7kg of enriched uranium was not enriched enough to be suitable for a nuclear weapon and terrorists would need tens, if not hundreds, of tonnes of the types of radioactive material unaccounted for at Lucas Heights to build a "dirty" bomb.

Herald Sun

http://www.news.com.au/common/story_page/0,4057,7956906%255E2,00.html