The Open Pool Australian Lightwater (OPAL) reactor

OPAL reactor project

In September 1997, following several major reviews into Australia's nuclear science and technology needs, the Commonwealth Government decided to fund a proposal by Australian Nuclear Science and Technology Organisation (ANSTO) to replace the ageing HIFAR (High Flux Australian Reactor) research reactor. The provision of funding was subject to, amongst other things, approval of the site and the design, approval of each major component of the nuclear plant, and an approval to operate by the CEO of ARPANSA. The following pages provide information on the licensing process and decisions made by the CEO for this project.

Stage 1 - siting licence

On 7 April 1999, the CEO of ARPANSA received an application from ANSTO for a facility licence authorising the preparation of a site for the proposed replacement research reactor. The CEO issued a licence for this purpose on 22 September 1999.

Stage 2 - construction licence

The next stage of the process was for ANSTO to submit an application for a facility licence authorising construction of the facility. On receipt of the application, ARPANSA performed a comprehensive safety evaluation of the proposal. This safety evaluation took into account world's best practice, advice from experts in the field, results of an International Peer Review of the Preliminary Safety Analysis Report (PSAR), and the views and concerns of individuals and organisations from the public arena. The CEO issued a licence to construct on 4 April 2002.

Stage 3 - operating licence

Following completion of the OPAL reactor Periodic Safety Review (PSR), on 22 October 2014, the CEO of ARPANSA decided to issue an amended facility licence to the ANSTO to operate a controlled facility (the OPAL reactor) at the ANSTO Lucas Heights Science and Technology Centre.

Modified fuel design for OPAL reactor

Following a fuel fault, discovered in July 2007, the OPAL reactor was shut down pending an investigation which resulted in a modification to the fuel design. On 1 May 2008, the CEO of ARPANSA, Dr John Loy, announced that he had approved a submission for a modified fuel design for the OPAL reactor.

The full decision and statement of reasons that accompanied it can be downloaded using the following link.

In his reasons, the CEO contemplated the imposition of additional licence conditions on the Opal reactor operating licence and provided ANSTO with an opportunity to make any submissions it wished on the proposed licence conditions. On 27 May 2008 ANSTO responded:

On 2 June 2008, the CEO imposed additional licence conditions contained in the following letter:

OPAL reactor heavy water isotopic purification system

Following the discovery of the ingress of lightwater into the heavy water moderator, ANSTO and the reactor designers (INVAP) proposed to construct and operate a heavy water purification system to maintain the performance of the reactor. On 24 June 2011, the acting CEO of ARPANSA Professor Peter Johnston approved the ANSTO submission for commissioning of the OPAL Reactor Heavy Water Isotopic Purification System plant. The plant intends to improve the current quality of the reactor reflector vessel heavy water. The commissioning stage approval had been preceded by separate ARPANSA approvals for the pre-commissioning and construction of the plant. Once the commissioning is completed and successful, ANSTO will request ARPANSA approval for routine operation.

Periodic safety review of the OPAL reactor

Schedule 2, licence condition 1, of the original OPAL reactor operating licence and later superseded by schedule 2, licence condition 13, of the amended licence (issued on 13 February 2014) requires ANSTO to conduct periodic safety reviews. ANSTO submitted the periodic safety review in the last quarter of 2011. This review re-examined the safety of the OPAL reactor taking into consideration operating experience from commissioning and the first two years of operation and international best practice. Apart from submitting the periodic safety review to ARPANSA, ANSTO was also required to seek international peer review. ARPANSA has assessed the review  and is satisfied that the information submitted provides adequate assurance of the ongoing safety of the OPAL reactor as currently operated