ANSTO has confirmed today that there is no safety risk to staff or the public from the reported light-water seepage into the reflector vessel which surrounds the OPAL reactor core. Nothing is leaking out of the reactor into the external environment.
ANSTO also said that reactor commissioning and operation can continue, and the seepage will have minimal effect on how the reactor is being utilised.
Tests carried out last week confirmed that a small amount of light-water in the pool surrounding the reactor’s reflector vessel, which houses the reactor, is seeping into the reflector vessel’s heavy water. The heavy water is designed to reflect neutrons released from the reactor back into the core.
OPAL’s designers, INVAP, are currently assessing the situation, and a team is working out the best way to fix it.
As the tests have confirmed that safety is not an issue, ANSTO is planning to take OPAL back to full power in the near future. The means that neutron production and commissioning of irradiation facilities can recommence.
ANSTO’s regulator ARPANSA is fully aware of the situation, and agrees that the seepage raises no safety concerns.