Q&A: Patrick O’Sullivan, International Atomic Energy Agency (IAEA)

Energy Focus talks to Patrick O’Sullivan, Decommissioning Specialist in the International Atomic Energy Agency (IAEA) Department of Nuclear Energy’s Waste Technology Section.

Q&A: Patrick O'Sullivan

What is the IAEA's role in the decommissioning of nuclear facilities and radioactive waste disposal?

The IAEA develops safety standards and associated guidance which, although not mandatory, typically provide the basis for the legal and regulatory infrastructure developed by IAEA member states. The IAEA is also mandated to gather and disseminate good practices on all aspects concerned with the peaceful uses of nuclear energy, including decommissioning planning and implementation. Finally, the Agency provides direct support through its technical cooperation programme, e.g. face-to-face and distance capacity building and training activities.

Where do you see the biggest opportunities in decommissioning and waste management across Europe over the next 5–10 years?

There are currently approximately 80 power reactors permanently shut down or under active decommissioning in Western Europe, and a further 30 or more may be shut down during the next decade. With the important exception of the gas-cooled reactors, for which management of irradiated graphite remains problematic, the generally preferred decommissioning strategy for these is to proceed directly to dismantling following a transition period during which the spent fuel is removed and the facility is prepared for decommissioning – including post-operation clean out, establishment of waste management systems, facility characterisation and preparation of safety and environmental impact studies for decommissioning. Important prospective activities arise in all these areas, as well as on aspects more directly associated with facility decontamination and dismantling. Similar considerations apply to other facilities of the nuclear fuel cycle and to management of legacy waste and associated storage facilities, e.g. from past research-related activities.

What can be done within the nuclear decommissioning sector to reduce uncertainty on projects?

Cost overruns are almost always associated with unanticipated changes to the planned project scope. Final costs are generally most sensitive to: (1) the end state of the facility and the associated land; (2) contamination levels, particularly unexpected contamination; (3) the extent to which dismantled materials can be cleared from regulatory control; and (4) the waste management options available for materials being managed as radioactive waste. Important uncertainties linked to these issues may be reduced by well-focused characterisation undertaken prior to decommissioning; early agreement on end state criteria with regulatory authorities; and establishment of waste treatment systems during the transition period. The IAEA has several initiatives to encourage the sharing of experience on these issues, including a network for decommissioning practitioners and a decommissioning wiki-based information resource.

Nuclear decommissioning trust funds have been established in several countries, whereas others rely on provisioning arrangements made by the facility owners. What is important is that oversight arrangements are in place to ensure that future costs are estimated with sufficient accuracy, taking account of uncertainties, and that financing arrangements are reviewed on a regular basis and modified as necessary to ensure that adequate provisions are made while revenues are being generated from the facility.

How can we  drive more innovation in decommissioning and waste management, so that projects can be delivered faster, cheaper and safer?

Cost, project duration and cumulative dose levels tend to be interlinked. Staff costs (e.g. for project management, engineering and other support activities) typically make up a significant proportion of total costs. Innovation begins with improvement in planning and project management: reducing the overall timeframe from shut down to completion of decommissioning is a key consideration in reducing overall costs. Other important costs are related to dismantling and removal of the plant and the waste management costs. For example, dose levels in pressurised water reactors plants can be significantly reduced by undertaking a prior system decontamination of the primary loop, thus enabling the dismantling to proceed more quickly and safely. Removal of large components in a single piece rather than their segmentation and packaging on-site also tends to reduce time and cost. Adopting or leveraging innovation developed in other fields brings significant benefits for decommissioning, e.g. early development of electronic 3D models of the plant, with superimposed dose levels, will also facilitate faster and safer dismantling. In addition, maximising the extent to which materials can be released from regulatory control and provision of suitable metal melting facilities, to facilitate recycling, will tend to reduce overall costs.

What do you see as the biggest challenges facing the decommissioning industry in Europe?

With the possible exception of damaged reactors, decommissioning of nuclear facilities can be fully implemented using currently available technologies. The most important single challenge is the current lack of waste management facilities, particularly for disposal of radioactive waste with significant long-lived components. Ensuring that sufficient numbers of appropriately qualified and trained people are available for the extensive timeframe over which decommissioning will occur, and the provision of systems to capture and transfer experience gained from ongoing projects, are also important.

How can we continue to improve cooperation and synergies across Europe?

Much has been achieved in terms of general harmonisation of standards, though there is still a wide diversity of approaches to waste management and the application of clearance in particular. Greater collaboration on research and development would likely accelerate acceptance of more advanced technologies in areas such as robotics, development of remote means of characterisation (e.g. using drone technology), virtual reality systems in preparation for dismantling activities, and the use of laser technology for cutting and decontamination, waste management in general and clearance in particular.

How can UK businesses break into supply chains in other countries?

The IAEA’s role in promoting harmonisation of safety standards, and in facilitating knowledge sharing on current good practices, is helping in this regard, e.g. by assisting member states to be ‘informed customers’ in selecting which technologies best correspond to their needs. It is likely that countries with small nuclear programmes will rely increasingly on external expertise to implement decommissioning activities.