- Antoinette Radford
- BBC reporter
image source,Western Australian Government
The hazardous device was eventually found near the town of Newman, which is on the 1400km route from the Gooday-Dari mine to Perth.
Authorities in Western Australia were faced with a seemingly impossible task when mining company Rio Tinto reported a capsule of radioactive cesium-137 missing on January 25.
Searchers had to find a pea-sized capsule along a 1,400-kilometre route. The line runs from the Gudai-Darri mine in northern Australia to a warehouse north of central Perth.
Authorities acted quickly, mobilizing professional search and rescue crews to find the capsule, and firefighters were pulled from their usual summer duties.
Experts from across the country were called in, including experts in nuclear science, emergency management agencies and radiation protection officials.
Authorities believe the capsule fell from a radiation measuring instrument on January 12 as it was being transported from the Rio Tinto mine to a storage facility on Perth’s north-eastern suburbs.
They believe that vibrations during transportation may have caused the bolts to loosen, causing the capsule to fall through the gap between the casing and the truck.
Cesium-137 capsules are commonly used in radiation measuring instruments in mining to determine the density of certain substances. But if a person comes into contact with it, it can cause severe burns and expose the body to radiation equivalent to 10 X-rays per hour.
Authorities began searching around the Perth and Newman mine sites on January 26 before informing the public of the threat.
On January 27, authorities issued an urgent health alert to inform the public of the risks posed by the radioactive capsules. Health authorities have a simple instruction for anyone who may come across the capsule: stay away.
“It emits both beta and gamma rays, so if you get close to it, you could get skin injuries, including burns,” the state’s chief health officer, Andy Robertson, warned.
Authorities fear it may have become lodged in the tire of a passing car.
image source,Radiation Services WA
Authorities believe the capsule fell from a radiation measuring instrument on January 12 as it was being transported from the Rio Tinto mine to a storage facility on Perth’s north-eastern suburbs.
By January 27, the search team was looking for the small capsule with all their might, but not with their eyes, but with portable radiation meters. The gauge is used to detect radioactive material within a radius of 20 meters.
“We’re not trying to find the little capsule by sight. Radiation equipment will hopefully lead us to it,” a police spokesman said the next day.
Police are focusing on the GPS route the truck was traveling on, as well as locations close to the Perth metropolitan area and high-density areas.
Police focused on a site along the Great Northern Highway on Jan. 28 after a resident reported unusual activity in a Geiger counter, a device used to measure radioactivity.
But this search was fruitless.
The next day, the additional resources requested from the Australian federal government were approved, and those in charge of the search began planning the next stage of work. The search began to accelerate as new equipment entered Western Australia and became operational on January 30.
Darryl Ray, incident controller for the state’s emergency services, described the new tools provided by the government as “specialized radiation detection equipment”.
Local media reported that new equipment used by searchers included radiation portal monitors and gamma-ray spectrometers.
Radiation portal monitors detect gamma radiation and are commonly used at airports to scan individuals to ensure travelers are free of radioactive material. A gamma ray spectrometer measures the intensity of the radiation.
Darryl Ray said the new detection equipment could be mounted on a vehicle so that it could be searched from a moving vehicle traveling at about 50km/h.
“It will take about 5 days to complete the original route, which is estimated to be 1,400 kilometers. The staff will drive north and south along the Great Northern Highway.” He said.
But by the end of January 31, the capsule was still missing.
“More than 660 kilometers have been searched so far and all agencies are grateful for their support,” the Department of Fire and Emergency Services said.
image source,Government of Western Australia
The capsule’s serial number allowed authorities to authenticate the capsule that was found.
And the next day, the near-impossible was achieved when the government revealed that the capsule had been found just two meters from the side of the road at 11:13 local time on Wednesday.
Authorities said search crews had “literally found a needle in a haystack”.
While authorities would not say exactly where the radioactive capsule was found, officials said it was the “best possible outcome”.
Local media reported that it was found about 74 kilometers from Newman, or about 200 kilometers from the mine.
No one appeared to be injured by the capsule, and it did not appear to have moved from where it fell, authorities said.
Fire and Emergency Services Commissioner Darren Klemm said a car traveling at 70km/h was found by investigative equipment used to detect radioactivity at the outset, paired with specialized equipment to physically locate the capsule. took it.
After a check of the serial number on the capsule, searchers confirmed it was correct.
Nigel Marks, an associate professor at Curtin University in Western Australia, hailed the discovery as a “victory for science”.
“You know it emits gamma radiation, so obviously look for something on the side of the road that has strong gamma rays … Sure enough, that’s where they found it.”
image source,Reuters
Emergency crews in Australia are hunting for radioactive capsules along the 1,400km route.
Dr. Max added that many “orphan radioactive sources” are lost and often cannot be found.
“It’s a regulatory failure, but I think it’s really cool how they figured it out.”
The chairman of Australia’s Radiological Council will now investigate how the capsules were misplaced in the first place.
The results of the report will determine whether charges will be brought against Rio Tinto.
After the capsules were discovered, Rio Tinto chief executive Simon Trott said the company would “cooperate fully” with the investigation.
He added that Rio Tinto would pay for the search if the government asked for it.