From:
s 22 - Irrelevant
Sent:
Saturday, 28 January 2023 10:51 AM
To:
s 22 - Irrelevant
Subject:
ARPANSA Update on missing radiation source in Western Australia - 28 January
2022 [SEC=OFFICIAL]
Please see below update from ARPANSA as of 10:30am 28 January 2022.
Background
A 19.9 Giga-becquerel (GBq) industrial radiation source in a level gauge was transported by road on a trailer
from s 22 - Irrelevant
in the Pilbara to the Perth metropolitan area
for s 22 - Irrelevant. The ceramic radioactive material was inside a metal capsule which is 6 mm diameter and 8 mm
long.
The source was packed on 10 January 2023 - secured in the gauge housing, then inside a transport box (to
which it was bolted), this was mounted on a pallet and initially storeds 22 - Irrelevant The Pallet was collected
and loaded onto a trailer by the s 22 - Irrelevanton 12 January 2023 for transport by road to Perth. It
travelled through some intermediate depots before arriving at the premises s 22 - Irrelevant in Malaga on 16
January 2023. The pallet was stored at those premises until being opened on 25 January 2023, when the
source was found to be missing. The source is thought to have fallen through a hole in the damaged box and
then from the trailer to the road.
Investigations by s 22 - Irrelevant
including physical and instrumental
searches of various sites and a section of the Great Northern Highway near Bindoon, have been conducted
and are continuing. These efforts to find the source have not been successful. The Department of Fire and
Emergency Services (DFES) is the Hazard Management Agency for the incident s 22 - Irrelevant
of the missing
material.
Situation Update
ARPANSA Duty Officer was contacted s 22 - Irrelevant
on Friday 27 January
advising that a Category IV radiation source (20GBq Cs-137) has become detached from the gauge during
transit between Wittenoom and Perth WA (approximately 1,400km distance) and requesting advice on any
available equipment that ARPANSA had which may assist in the recovery of the lost source noting the
by ARPANSA under FOI
extensive distance. WA Health also requested advice from ARPANSA to validate their calculations of any
possible health risk (dose estimates).
ARPANSA advised s 22 - Irrelevantthat we have two different vehicle-based detection systems and confirmed
with them possible timing of mid-week next week for any possible delivery to allow sufficient time to make
planning arrangements and for ARPANSA to prepare the system for deployment.
o Noting the significant search area, further work is required by ARPANSA to calculate the maximum
speed at which any vehicle can travel whilst not compromising detection capability.
A formal Request for Assistance s 22 - Irrelevant
for Australian
Government assistance to locate the missing radiation source, namely:
o Specialised radiation detection capability, to locate 20 giga-becquerel of Caesium-137 up to 10 to 15
metres off the side of the road.
Released
o The total distance of road is estimated as 1350km of regional highways and would also include some
metropolitan road routes.
o The request is a priority, with the requirement for the equipment to be on the ground into Perth by
no later than Wednesday 1 February 2023. The duration of the request is unknown at this stage and
would be dependent on the ground coverage area of the capability provided.
1
