Investigation into Australia's radioactive capsule begins

STORY: An investigation is underway into how exactly a radioactive capsule fell out of a truck and got lost along a 870 mile stretch of the arid Western Australian outback.

Verified by members of Australia's Defence Force and sealed in a lead container, the Caesium-137 capsule, just 6mm in diameter and 8mm long, is being escorted to Perth by a team of 14, including nuclear specialists.

Here's Western Australian chief health officer, Andrew Robertson.

“We will be looking at the manufacturer of the gauge, how it was set up at the mine site, how it was taken down, how it was packed and the transfer and then obviously receipt and whether that was all done in accordance with the radiation safety act and the transport regulations.”

Authorities believe the gauge broke apart on the journey, dislodging the capsule which then fell out of its crate and from the truck - a road train with multiple trailers.

Department of Fire and Emergency Services Incident Controller Darryl Ray said a search team found it when radiation equipment mounted to their car detected gamma rays.

“Everything spiked and their computers went mad and they hit the brakes. Flew out of the vehicle in excitement. We took control of the scene, set up a hazmat (hazardous material) zone, a hot zone, controlled the entry. We verified the source with three different pieces of equipment as well.”

“It wasn’t found by luck, it was found by a lot of specialists. A very dedicated team from many different agencies and organizations both state and from the commonwealth. And believe it or not I was pretty confident since day one to actually find it."

Officials say no one is thought to have been exposed to radiation and the site on the Great Northern Highway was not permanently contaminated.

The capsule was part of a gauge used at one of Rio Tinto's iron ore mines.

The company has also launched its own investigation and offered to reimburse the cost of the search.

It has also said it will cooperate fully with the official investigation.

The maximum penalty for failing to safely handle radioactive substances is around $700, and $35 extra for every day the offense continues - though the state government has flagged new rules with bigger penalties.

Prosecutions would be considered under state radiation safety laws dating to 1975.