The 13th International Conference on Environmental ... - Events

Abstracts
shearing tools have been developed to cut the reactor internals. All of those equipments are hydraulically driven which is
very suitable for submerged applications. Mechanical cutting has a number of advantages compared to other cutting
techniques. ? <strong>The</strong> technique produces almost no secondary waste. ? <strong>The</strong> visibility during cutting is very good because the
cutting produces only a negligible amount of micro particles. ? Chips from the cutting process falls down to the bottom of
the cutting pool and are easy to collect. ? No gases are produced that can cause airborne contamination. ? <strong>The</strong> technique
is safe and reliable. ? All reactor internal sizes, materials and thicknesses can be cut.
Westinghouse experience in mechanical cutting has demonstrated that it is an excellent technique for segmentation
of internals. Westinghouse continues to develop new methods and products in order to further reduce the waste volume.
In summary, the purpose of this paper will be to provide an overview of the Westinghouse mechanical segmentation
process, based on actual experience from the work that has been completed to date.
2) 40130 – EPRI Nuclear Power Plant Decommissioning Technology Program
Karen Kim, Sean Bushart, Mike Naughton, Richard McGrath, Electrict Power Research Institute (USA)
<strong>The</strong> Electric Power Research Institute (EPRI) is a non-profit research organization that supports the energy industry.
<strong>The</strong> Nuclear Power Plant Decommissioning Technology Program conducts research and develops technology for the safe
and efficient decommissioning of nuclear power plants.
Several USA nuclear power plants shut down and entered active decommissioning in the 1990s. At that time the
decommissioning of a commercial nuclear power plant was a first of a kind evolution; nuclear power plant
decommissioning is a combination of industrial decommissioning with the complexities of radioactive materials and
waste management. <strong>The</strong> first plants to undergo this process encountered various challenges related to decommissioning
planning and project management, removal of large radioactive components, radiation protection, site remediation, final
status survey, and license termination. <strong>The</strong> USA regulatory framework for nuclear power plant decommissioning
developed and evolved along with these first decommissioning projects. As of 2009 these nuclear power plants have
successfully completed decommissioning activities and have achieved license termination. Two major contributors to the
successful completion of these projects were a) the development of technology specifically tailored to tasks unique to
nuclear plant decommissioning and b) learning from each other’s experiences.
<strong>The</strong> EPRI Nuclear Power Plant Decommissioning Technology Program conducts research and develops technology
that addresses the range of decommissioning tasks from pre-planning, site characterization, removal of large components,
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. <strong>The</strong> 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 <strong>International</strong> 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. <strong>The</strong> 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, <strong>The</strong> 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. <strong>The</strong> 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. <strong>The</strong> 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).
<strong>The</strong> SRUs are huge component (7ton, �6.3m, 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. <strong>The</strong>refore, 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. <strong>The</strong> 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.
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