Opal News
OPAL news
We expect to resume operations once there is regulatory approval from ARPANSA. The fuel-plate displacements found during a routine shutdown in July 2007 resulted in a design change, i.e. the incorporation of a stopper to prevent fuel-plate movement. The revised design has been thoroughly tested and evaluated, including tests that exceeded conditions that would be experienced in the reactor. ANSTO has undertaken detailed risk assessments and technical analyses, in collaboration with the reactor designer INVAP and drawing upon the advice of independent international experts. Documentation on the modifications was submitted to our regulator ARPANSA in December 2007. If ARPANSA approval is received, operation of OPAL will recommence using fuel manufactured to the new design.
This shutdown has also enabled ANSTO to successfully complete a set of unrelated repairs to the reflector vessel, which contains heavy water. The very small leaks of light water into the heavy water in the vessel would gradually have affected the efficiency of neutron production over several years if not resolved.