ASME Message

Abstracts
site remediation, to license termination. A key feature of the EPRI Program is the collection and transfer of lessons
learned and experiences from the major decommissioning projects conducted to date. The EPRI Program conducts
research and development based on the needs of its utility members; the EPRI Program membership consists of utilities
from the USA, France, Spain, Sweden, Italy, Taiwan, and Japan. EPRI is the mechanism through which these
international utilities can conduct collaborative research and development and learn from each other’s experiences and
lessons learned. In addition to collaborative research and development, the EPRI Program Team of decommissioning
experts provides direct and site-specific support to its member utilities to facilitate knowledge transfer and
decommissioning project optimization.
This presentation will provide information about the EPRI Nuclear Power Plant Decommissioning Technology
Program and discuss USA and International Decommissioning experiences to date.
3) 40253 – Tokai-1 Decommissioning Project
Keizaburou Yoshino , JAPC (Japan)
Tokai-1 is the oldest and historical commercial Magnox reactor in Japan, which had started commercial operation in
1966. The unit had helped introduction and establishment of the construction and operation technologies regarding
nuclear power plant at early stage in Japan by its construction and operating experiences. However, The Japan Atomic
Power Company (JAPC), the operator and owner of Tokai-1, decided to cease its operation permanently because of a
fulfillment of its mission and economical reason. The unit was finally ceased in March 1998 after about 32 year operation.
It took about three years for removal of all spent fuels from the site, and then decommissioning started in 2001. JAPC,
always on the forefront of the nation’s nuclear power generation, is now grappling Japan’s first decommissioning of a
commercial nuclear power plant, striving to establish effective, advanced decommissioning. The decommissioning for
Tokai-1 was scheduled as 20 years project. At the beginning, the reactor was started to be in a static condition for ten
years (“safe storage period”). While the reactor had been safely stored, the phased decommissioning works started from
non-radioactive or low radioactive equipments toward high radioactive equipments. First five years of the project, JAPC
concentrated to drain and clean spent fuel cartridge cooling pond and to remove conventional equipments such as turbine,
feed water pump and fuel charge machine as planed and budgeted.
From 2006, the project came into new phase. JAPC has been trying to remove four Steam Raising Units (SRUs).
The SRUs are huge component (7ton, φ6.3m, H24.7m) of the Gas Cooling Reactor (GCR) and inside of the SRUs are
radioactively contaminated. It is concerned that workers are required safety and minimizing contamination areas during
SRU removal. Therefore, JAPC is developing and introducing Jack-down method and remote control multi functional
removal system. This method is the method by which to remove the SRUs in turn from the bottom by lifting the SRU by
a large jack and cutting for removing SRU is done remotely with this system. The system enables cutting and holding not
only SRU body but also internals. This technology and experiences would be useful for the reactor removal in the near
future.
4) 40289 – Activities of the OECD/NEA WPDD in the Field of Decommissioning
Claudio Pescatore, Patrick O'Sullivan, OECD/NEA
The OECD/NEA seeks to assist its member countries in developing strategies for the management of all types of
radioactive material, including waste, that are safe and sustainable and that meet the broad needs of society - with
particular emphasis on the management of long-lived waste and spent fuel and on decommissioning of disused nuclear
facilities. The programme of work in the area of decommissioning is supervised by the Radioactive Waste Management
Committee (RWMC) and carried out by the Working Party on Decommissioning and Dismantling (WPDD). The latter is
made of senior representatives from regulatory authorities, decommissioning organisations, policy making bodies, and
researchand-development institutions from the NEA countries. It includes also representatives of the IAEA and of the the
European Commission. The WPDD supports the RWMC by keeping under review the policy, strategic, and regulatory
aspects of decommissioning of phased-out nuclear installations. Its scope of work includes decommissioning and
dismantling of shutdown facilities up to and including the release of the site, but excluding fuel removal, removal of
nuclear processing fluids, post-operational clean out of fuel residues and removal of operational wastes. The work
programme comprises activities in the following key areas: Policy, regulation and strategy; Funding and costs;
Techniques; Decommissioning materials management and site release; and Human and organisational factors. Recent
trends in the above areas, as noted in a recent analysis by the WPDD, include: • Policy, regulations and strategy – most
countries have adopted policies for decommissioning and for funding provisioning but a range of options were being
applied to the decommissioning of nuclear power plants (early dismantling, safe store and entombment), • Funding and
costs – cost calculations for decommissioning are very sensitive to the assumed end-state and to the levels of
contaminations on the sites and may be greatly influenced by stakeholder requirements, • Techniques – the focus of
current R&D is on the development of innovative technology for segmentation, dismantling and concrete
decontamination, together with better instrumentation for material management and control • Materials management and
site release – there is a significant acceleration in the number of decommissioning projects, including provision of
infrastructure for storage of materials and for undertaking clearance and recycling of disused materials; • Human and
organisational factors – efforts are being made to structure decommissioning contracts to optimise the supply chain
relationships, with greater transparency and better communication amongst all concerned parties; and • Stakeholder
participation and knowledge management – there is a range of approaches to stakeholder involvement in developing
decommissioning plans and to rule making. In general, this issue is gaining momentum. A number of specific activities,
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