ICEM11 Final Program 9.7.11pm_ICEM07 Final Program ... - Events

Session 6 Abstracts
2) GROUNDWATER FLOW MODELING OF PERIODS WITH TEMPERATE CLIMATE CONDITIONS FOR USE IN
A SAFETY ASSESSMENT OF A REPOSITORY FOR SPENT NUCLEAR FUEL (w/oP-59154)
Steven Joyce, Lee Hartley, Serco; Trevor Simpson, Serco (UK)
As a part of the license application for a final repository for spent nuclear fuel, the Swedish Nuclear Fuel and Waste Management
Company (SKB) has prepared a safety report (SR-Site) that assesses the long-term radiological safety after closure of a repository
located at 500 m depth in the Forsmark area, c. 120 km north of Stockholm. The movement and composition of groundwater
affect both the key pathways for radionuclide migration and the performance of engineered barriers, and hence are important issues
that have to be considered and modelled as part of quantitative assessment calculations. This presentation describes the groundwater
flow modelling studies that have been performed to represent the post-closure hydrogeological and hydrochemical situations
during temperate climate conditions, and how these are used to support safety assessment calculations and arguments.
The collation and implementation of onsite hydrogeological and hydrogeochemical data from the surface based site investigations
at Forsmark are used as the basis for defining a reference case for the natural hydrogeological situation at the site (hydrogeological
base case). Areas of uncertainty within the current site understanding and the engineered system are examined by a
series of flow model variants. The flow modelling needs to consider a wide range of…
3) CONCEPTION OF A NEW CONDITIONING PROCESS, OF STRONGLY PLUTONIUM
CONTAMINATED WASTE CANISTERS (w/oP-59205)
Maxime Michel-Noel, ONET Technologies-ONECTRA (France)
Intermediate storage in the Pegase nuclear facilities, of wastes strongly contaminated with plutonium and conditioned in 100
litres canisters, was no longer possible due to the new safety evaluation of this installation. A new process have been then imagined
to transform all these canisters in new confined packages inside the building itself. The conception, which is described, is based
on safety risk analysis which has been conducted before the construction.The operation itself is now terminated.
4) METHODOLOGICAL GUIDE ON DEVELOPMENT OF WORK PLAN FOR MITIGATION OF ACCIDENT
CONSEQUENCES DURING TRANSPORTATION OF RADIOISOTOPE THERMOELECTRIC GENERATORS AND
RADIOISOTOPE HEAT SOURCES (w/oP-59162)
Valeriy Shempelev, Scientific and Engineering Centre for Nuclear and Radiation Safety; Vladimir Reka, Rostechnadzor;
Malgorzata Sneve, Norwegian Radiation Protection Authority; Alexander Smetnik, Evgenij Kapralov,
FSUE VO “Safety”; Galina Zubareva, Tver State Medical Academy (Russia/Norway)
This methodological Guide has been built on the requirements of the regulatory acts of the Russian Federation, federal codes
and standards in the field of atomic energy, and also recommendations of the IAEA regulating the issues of safety during transportation
of radioactive material, and is intended to provide methodological aid to the operation organizations (operators), consignors
and consignees, when planning and organization of work on mitigation of accident consequences during transportation of
Radioisotope Thermoelectric Generators (RTG) and Radioisotope Heat Sources (RHS) by transport of all types, by land, air and
water all over the territory of the Russian Federation.
The methodological Guide contains recommendation on the procedure of preparation and execution of the Work Plan for mitigation
of accident consequences and its sections, as well as a standard model of the Plan and agreement with emergency and rescue
units for implementation of work to prevent transport incidents and accidents when transporting RTG and RHS drafted on the
basis of results of generalizing the real plans developed by the operating organizations. RTG utilize heat energy from radioactive
isotopes, in this case 90Sr and its daughter nuclide 90Y, to generate electricity as a power source.
5) PHYSICAL AND CHEMICAL PROCESSES DURING VACUUM DRYING
OF METALLIC SPENT NUCLEAR FUEL (wP-59114)
Martin Plys, Michael Epstein, Sung Jin Lee, Robert Apthorpe, Fauske & Associates LLC (USA)
A key process step in remediation of metallic spent nuclear fuel is vacuum drying, in order to move such fuel from pool storage
to dry storage. The drying process for metallic spent nuclear fuel is complicated by the fact that it must accommodate failed
fuel elements, scrap pieces of fuel elements, and scrap particulate. A number of physical and chemical processes that must be considered
in order to effectively and safely vacuum dry these materials are discussed in this paper including: (1) Exothermic oxidation
of exposed metallic surfaces, (2) The impact of uranium hydrides that may be present, (3) The potential for thermal instability,
(4) Degradation of thermal conductivity at low pressures, (5) Multi-component diffusion in scrap and particulate, and (6) Behavior
of uranium oxide hydrates.
We have addressed these issues by creating models for the individual phenomena that are based upon experimental data, integrating
these models into the process simulation code, FATE, and validating process simulations against closed-form solutions. The
integrated model has been employed during the conceptual and preliminary design phases for vacuum drying of scrap particulate
at Hanford in order to converge upon design and operational features that are demonstrably robust and therefore minimize safetyrelated
technical specifications
6) SECURITY ISSUES FOR LONG-TERM STORAGE OF USED FUEL (w/oP-59380)
Felicia A Durán, Gregory Wyss, Calvin Jaeger, Sandia National Laboratories (USA)
With the uncertain future of the proposed Yucca Mountain Repository for final disposal of used light water reactor fuel, the
need to store these fuels past their current regulatory certification periods has become clear. This situation presents possible regulatory
and technical issues with regard to both storage safety and security. The U.S Department of Energy (DOE), Office of Nuclear
Energy (NE) is engaged in a program to develop the technical bases for extending dry storage and subsequent transportation of used
nuclear fuel (UNF). The DOE/NE program addressing this issue is divided into four main topical areas: Research and Development
(R&D) Opportunities, Security, Transportation, and Concept Evaluations. This paper will discuss work to address security
issues for long-term storage of UNF. The timeframe for long-term management of UNF is currently defined to be on the order of
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