last update: 22-07-2018


The scope of CAST was defined through a process of consultation initiated by a questionnaire circulated to a wide range of organisations. A synthesis of the responses to the questionnaire showed that 14C release from irradiated steels, Zircaloys, graphites and from ion-exchange resins were of widest interest. The responses indicated that there were several on-going (or planned studies) on irradiated graphites and uncertainties on 14C release rates and speciation remain to be resolved. However, there was less on-going work and little information available, for the release of 14C from irradiated steels, Zircaloys and ion-exchange resins.

The objectives of CAST were to:

a) gain a scientific understanding of the 14C release mechanisms and rates from the corrosion of irradiated steels and Zircaloys and from the leaching of ion-exchange resins and irradiated graphites under geological disposal conditions;
b) provide speciation of the 14C release and how this relates to aqueous conditions;
c) evaluate this understanding in the context of national safety assessments; and
d) disseminate this understanding and its relevance to safety assessments to a range of interested stakeholders and provide an opportunity for training of early career researchers.

These objectives address Topic 2 in Key Topic 2 of the Implementing Geological Disposal- Technology Platform (IGD-TP) Strategic Research Agenda, which identifies a need for improved data and understanding of the underpinning scientific mechanisms of the release of radionuclides and chemical species from various long-lived Intermediate Level Wastes. This includes detailed characterisation methods, issues related to adequate inventory determinations, chemical form, speciation on release and transport in the near field and far field.


Click on a photo for a complete view.

This photo shows waste package than can contain
irradiated zircaloy and steel
This photo shows the remote
handling of this package
containing these irradiated metals
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