Authorities suspect vibrations from the truck caused the screws and the bolt to come loose, and the radioactive capsule from the gauge fell out of the package and then out of a gap in the truck. "We are taking this incident very seriously. We recognise this is clearly very concerning and are sorry for the alarm it has caused in the Western Australian community," Simon Trott, Rio's iron ore division chief, said in a statement. The silver capsule, 6 millimetres (mm) in diameter and 8 mm long, contains Caesium-137 which emits radiation equal to 10 X-rays per hour. Authorities have recommended people stay at least five metres (16.5 feet) away as exposure could cause radiation burns or radiation sickness, though they add that the risk to the general community is relatively low.
"From what I have read, if you drive past it, the risk is equivalent to an X-ray. But if you stand next to it or you handle it, it could be very dangerous," said Stuchbery. The state's emergency services department has established a hazard management team and has brought in specialised equipment that includes portable radiation survey meters to detect radiation levels across a 20-metre radius and which can be used from moving vehicles. Trott said Rio had engaged a third-party contractor, with appropriate expertise and certification, to safely package and transport the gauge.
"We have completed radiological surveys of all areas on site where the device had been, and surveyed roads within the mine site as well as the access road leading away from the Gudai-Darri mine site," he said, adding that Rio was also conducting its own investigation into how the loss occurred.
Analysts said that the transport of dangerous goods to and
from mine sites was routine, adding that such incidents have
been extremely rare and did not reflect poor safety standards on
Rio's part.
The incident is another headache for the mining giant
following its 2020 destruction of two ancient and sacred rock
shelters in the Pilbara region of Western Australia for an iron
ore mine.
(Reporting by Melanie Burton; Editing by Edwina Gibbs)
