Establishing a radioanalytical capability to support cyclotron decomissioning
Loading...
Date
2022-11-20
Journal Title
Journal ISSN
Volume Title
Publisher
South Pacific Environmental Radioactivity Association
Abstract
The 30 MeV cyclotron at the National Medical Cyclotron (NMC) ceased operations in October 2009 after producing medical isotopes for application in nuclear medicine for approximately 20 years.
Upon its closure a process of decommissioning commenced. Initially, internal components that make up the cyclotron were removed, leaving behind the vault. The vault is predominantly constructed of concrete and steel reinforcements. Neutron activation of these materials produced radioisotopes that will need to be accurately identified and quantified to support decision making around storage and disposal options of these materials. This is a critical aspect of any cyclotron decommissioning project and has safety, environmental and economic implications.
A capability to quantify typical radionuclides found in cyclotron materials is being developed at ANSTO. Cyclotron vault materials that may require assessment are concrete, steel and waters. Radionuclides of interest are typically beta- and gamma-emitting neutron activation products.
Non-destructive, high resolution gamma spectrometry will be applied to quantify gamma emitting radionuclides such as 152Eu, 154Eu, 134Cs and 60Co. The complex matrix of some reactor materials will cause attenuation of gamma photons and empirical and/or theoretical corrections will be applied. Beta-emitting radionuclides will require a suite of destructive radioanalytical techniques designed to isolate and quantify beta-emitting radionuclides such as 59Fe and 55Fe. Gross beta counting will assist in identifying which samples will require destructive beta analysis.
This presentation will outline the approach taken in identifying a sampling strategy and in the method development for non-destructive and destructive analysis and how this can support future cyclotron decommissioning needs of Australia and our region.
Description
Keywords
Cyclotrons, Isotopes, Nuclear medicine, Radiopharmaceuticals, Decommissioning, Steels, Reinforced materials, Radioisotopes, ANSTO
Citation
Thiruvoth, S., Harrison, J., Bedwell-Wilson, J., Cunynghame, T., Martiniello, J., Mokhber Shahin, L., & Silitonga, A. Establishing a radioanalytical capability to support cyclotron decomissioning. (2022). Presentation to SPERA 2022 - Connecting People, developing solutions for a Changing Environment, 28-30 November 2022, Chrischurch, New Zealand, (pp. 37). Retrieved from: https://au-admin.eventscloud.com/file_uploads/baa6bb17538b457fbd436f1552075bea_SPERA2022e-handbook.pdf