ASME Message

Abstracts
projects and reports address the above areas. They will be reviewed for the ICEM-2010 audience
5) 40307 – French Decommissioning Feedback Experience and Lessons Learned
Jean-Guy Nokhamzon, CEA (France); Patrick O'Sullivan, OECD/NEA
The French (CEA, EDF and AREVA) experience in decommissioning of nuclear facilities goes back many decades
and relates to many installations of very different types.
Some twenty facilities were dealt with by 2009, corresponding to around half of all the nuclear facilities
permanently closed up to date, beginning in March 2001 with the decommissioning of AT1 facility at La Hague, the pilot
plant used by the CEA in the seventies for the reprocessing of spent fuel from fast neutron reactors (former IAEA stage 3,
excluding the civil engineering structures), as well as the blasting of G1 stack at Marcoule, on 19 July 2003 and ending
with the total demolition of the research reactors Triton and Néréide in Fontenay aux Roses in 2004 and the final steps
for the total decommissioning of Siloë, Siloette and Mélusine in Grenoble research Centre by 2012.
All the work done demonstrates the following:
1) Decommissioning can and has been done in a safe, cost-effective and environmentally friendly manner.
2) Current technologies have demonstrated their effectiveness and robust performance in numerous
decommissioning activities. Feedback experience on design, construction and operation is a considerable help for
reliable planning, cost evaluation and successful realization of a decommissioning project.
3) During decommissioning radiological risks are very small in comparison to non-radiological risks.
4) The dissemination of best practices and sharing of information in international workshops, conferences and
especially within working groups as the OECD/NEA/CPD and IAEA/IDN has proven to be a good basis for an
effective cooperation and support to master new challenges on decommissioning projects.
5) Future challenges will require further international cooperation to establish sustainable regulations and
guidance to achieve objectives without being burdensome or overly conservative.
6) A consistent, internationally accepted rationale is necessary for the elaboration of concepts and for the
derivation of numerical values on clearance, exemption and authorized releases.
7) With decommissioning moving towards being a fully mature industrial process, increased dialogue among
regulators, implementers and international standards organisations is necessary.
6) 40032 – Decommissioning Planning for Swedish Operating NPPs
Gunnar Hedin, Mathias Edelborg, Niklas Bergh, Westinghouse Electric Sweden (Sweden); Jan Carlsson, Fredrik
de la Gardie, SKB (Sweden)
Decommissioning studies have been carried out for the three BWR units of Oskarshamn and the three BWR units of
Forsmark nuclear power plants. The final closure of these units is far ahead but anyhow there has been a need for
developing a more general decommissioning planning basis. The main objectives of the studies have been to establish an
estimate of the waste amounts arising from these units during decommissioning and dismantling as well as providing a
firm basis for funding of the decommissioning phase for these units. The waste amounts will be used when designing a
separate repository for decommissioning waste of the same type as the existing facility for final disposal of short-lived
low- and intermediate level waste, the SFR, at Forsmark, Sweden. The broader studies are also used for verification that
the existing national decommissioning fund is of an adequate size.
The studies have been performed by Westinghouse in cooperation with the utilities of Forsmark (FKA) and
Oskarshamn (OKG), on behalf of SKB, the utility-owned Swedish waste management organization, responsible for
coordination of the national waste fund as well as for designing, building and operation of waste management facilities.
Each of the studies contains a general description of the plant with the purpose to characterize them to facilitate
decommissioning project comparative studies of different plants. Also, a detailed inventory of all materials in the plant
have been put together and modeling of radioactivity data have been carried out to establish typical contamination levels
for the main parts of the plant. The procedures and technologies foreseen to be used for the future dismantling and waste
management work are briefly described based on standard, presently easily available techniques.
The combination of the materials inventory data and the radiological data is used to calculate the number of
different waste containers that will be produced during dismantling of the plant. Standard 20 feet ISO containers will be
used for the low-level waste while special steel containers that fit the transport overpack system will be used for
intermediate level waste. The long-lived waste will be loaded into thick-walled steel containers.
The inventory data will also be used by experience models that calculate work hours for taking care of all the
different types of plant components. The working time estimates are then combined, together with general duration data
for different activities during plant decommissioning, into a time schedule for the complete program, from initial
planning and preparatory activities to non-radioactive building demolition and site restoration.
Costs are then estimated for each of the work breakdown structure (WBS) elements of the time schedule.
Summarized it provides a budgetary estimate for the complete decommissioning program. By rearranging the elements of
the cost estimate according to the IAEA/EC/OECD-NEA common matrix (the “Yellow Book”), cost comparison with
other plants is facilitated.
The paper will provide detailed data of waste characterization and amounts, as well as of time schedules and cost
estimates for the main part of the Swedish BWR fleet and show how decommissioning will fit with the existing
-45-