The missing radioactive capsule was found on a remote road in Australia

Brisbane, Australia
CNN
—

Authorities scanning a remote Australian highway for a small missing radioactive capsule found it by the side of the road after a challenging search likened to trying to find a needle in a haystack.

State emergency services announced the discovery Wednesday afternoon, six days after the capsule, containing highly radioactive cesium-137, was discovered missing from a package sent hundreds of kilometers from a Rio Tinto mining site in northern Western Australia to the capital Perth.

“Finding this site has been a monumental challenge – the search parties have literally found the needle in the haystack,” Minister of State for Emergencies Stephen Dawson told a news conference on Wednesday.

The capsule’s disappearance prompted a massive search of the highway by specialist radiation detection units – and prompted warnings to the public to stay away from the capsule, which could cause serious burns if it comes in contact with the skin.

Authorities believe the capsule – about 8 millimeters high and 6 millimeters round – somehow fell off the back of a truck while being transported 1,400 kilometers (870 miles) along the Great Northern Highway from the mine.

Rio Tinto, which used the device in a meter at its Gudai-Darri iron ore mine, said it regularly transports and stores dangerous goods as part of its business and employs expert contractors to handle radioactive materials.

In a statement on Wednesday, chief executive Simon Trott said the company was “incredibly grateful” for the work undertaken to find the capsule and once again apologized to the community for its loss.

“While the recovery of the capsule is a great testament to the skill and tenacity of the search team, the fact is that it should never have been lost in the first place,” he said. “We are taking this incident very seriously and are undertaking a full and thorough investigation into how it happened.”

Authorities said the missing capsule was found at 11:13 a.m. local time Wednesday, two meters from a road south of the small town of Newman by crews using radiation detection equipment.

Officials said a 20-meter exclusion zone has been created around the capsule and it will be transferred to a lead container before being taken to a security facility in Newman.

On Thursday, he will begin his journey south again – this time to a health facility in Perth.

Chief health officer and chairman of the Radiological Board, Andrew Robertson, said it did not appear that anyone had been exposed to radiation from the capsule during its absence.

“It doesn’t appear to have moved – it appears to have gone off the track and landed on the side of the road. It’s remote enough that it’s not in a large community, so it’s unlikely that anyone was exposed to the capsule,” he said.

Washington’s Department of Emergency Services (DFES) raised the alarm on Friday, warning residents of a radioactive spill across the state, including in the northeastern suburbs of Perth, home to about 2 million people.

According to authorities, the capsule was placed in a package on January 10 and taken from Rio Tinto’s Gudai-Darri mine by a contractor on January 12.

The vehicle spent four days en route and arrived in Perth on January 16, but was only unloaded for inspection on January 25 – when it was discovered the capsule was missing.

The incident came as a shock to experts, who said the handling of radioactive materials such as cesium-137 is tightly regulated, with strict protocols for its transport, storage and disposal.

Radiation Services WA says radioactive material is transported throughout Western Australia on a daily basis without any problems. “In this case, there appears to have been a failure of normally applied control measures,” it said in a statement, adding that it had nothing to do with the loss of the capsule.

DFES Commissioner Darren Klemm said the capsule was found in the “best possible area” due to its remote location and finding it in such a short time was “incredible”.

“A lot of work was done around the metro area based on some intelligence early on … so you can’t help but imagine there was an element of surprise for the people in the car when the equipment jumped,” he said.

Cesium-137 can cause serious health problems for people who come into contact with it: burns from close exposure, radiation sickness, and potentially deadly cancer risks, especially for those who have been unknowingly exposed for long periods of time.

Robertson, the chief health officer, said standing one meter from the capsule for one hour would be equivalent to receiving a radiation dose of 10 X-rays.

Officials feared the capsule might have gotten caught in the tires of another vehicle and been transported away from the search area. It could also have been taken from the area by an animal – or worse, taken and kept by someone who was unaware of the dangers.

And the risk wasn’t just in the short term – cesium-137 has a half-life of around 30 years, meaning that after three decades the capsule’s radioactivity will halve and after 60 years it will halve again, meaning the loss the capsule can remain radioactive up to 300 years.

Robertson said it was unlikely the capsule had contaminated the surrounding soil because it sat unattended for days by the side of the highway.

“It’s encased in stainless steel, so it’s unlikely, unless there’s been significant damage to the source itself, which is unlikely from falling off the back of a truck, that there’s going to be any contamination in the area.”

Robertson is investigating the disappearance of the capsule and will present a report to the Minister for Health in the coming weeks.

Dawson, the emergency services minister, said the recovery of the capsule was an “outstanding result”.

“I think West Australians can sleep better tonight,” he added.