Browsing by Author "Dimitrovski, L"

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    ANSTO's radioactive waste management policy: preliminary environmental review
    (Australian Nuclear Science and Technology Organisation, 1996-05) Levins, DM; Airey, PL; Breadner, B; Bull, PS; Camilleri, A; Dimitrovski, L; Gorman, T; Harries, JR; Innes, RW; Jarquin, E; Jay, G; Ridal, A; Smith, AM
    For over forty years radioactive wastes have been generated by ANSTO (and its predecessor the AAEC) from the operation of nuclear facilities the production of radioisotopes for medical and industrial use and from various research activities. The quantities and activities of radioactive waste currently at Lucas Heights are very small compared to many other nuclear facilities overseas especially those in countries with nuclear power program. Nevertheless in the absence of a repository for nuclear wastes in Australia and guidelines for waste conditioning the waste inventory has been growing steadily. This report reviews the status of radioactive waste management at ANSTO including spent fuel management treatment of effluents and environmental monitoring. It gives details of: relevant legislative regulatory and related requirements; sources and types of radioactive waste generated at ANSTO; waste quantities and activities (both cumulative and annual arisings); existing practices and procedures for waste management and environmental monitoring; recommended broad strategies for dealing with radioactive waste management issues. Detailed proposals on how the recommendations should be implemented is the subject of a companion internal document the Radioactive Waste Management Action Plan 1996-2000 which provides details of the tasks to be undertaken milestones and resource requirements.
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    Australian research reactors spent fuel management: the path to sustainability
    (European Nuclear Society, 2016-03-13) Finlay, MR; Miller, R; Dimitrovski, L; Domingo, X; Landau, P; Valery, J; Laloy, V
    Since the late 1950’s, ANSTO has successfully operated three research reactors in Australia: HIFAR (1958-2007), MOATA (1961-1995) and OPAL (2006- Specific strategies were developed and implemented for the management and disposition of spent fuel from HIFAR and MOATA. They included strategic considerations, technical options, fuel characteristics, storage capacity, operational constraints and associated implications. In addition, the operating licenses of the Australian reactors have required the identification of spent fuel disposition arrangements, i.e. the “deferment” strategy of storage indefinitely is not acceptable. Disposition then employed three routes with direct disposal in the USA under the US-DOE FRRSNFA Program and reprocessing in France by AREVA, and in the UK by the UKAEA. Both reprocessing routes included return of vitrified waste. ANSTO and AREVA have worked together since the late 1990’s on the disposition of uranium aluminide (UAlx) spent fuel from HIFAR. Today, ANSTO is committed to develop a lifetime strategy for management and disposition of uranium silicide (U3Si2) spent fuel from OPAL. AREVA’s ability to offer an integrated solution for storage, transport, reprocessing, waste return and long-term management, including addressing individual customer needs (type of fuel, timelines, quantities, final waste management strategy,...), has provided ANSTO with a viable spent fuel management strategy, for OPAL’s lifetime.
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    Forty-nine years of safe storage of research reactor spent fuel at ANSTO
    (International Atomic Energy Agency (IAEA), 2009-10-19) Dimitrovski, L; Anderson, M
    ANSTO permanently shut down its 10 MW research reactor (HIFAR) in January 2007 following 49 years of operation. The shutdown followed the earlier closure of a smaller 100 kW research reactor (MOATA) in 1995. The spent fuel resulting from the operation of the HIFAR and MOATA reactors (2281 elements) was stored in wet and dry storage facilities. Of the 2281 spent fuel elements produced only 19 incurred some degree of “damage”, either physical or chemical. Until recently (2007) some of these elements were still kept in dry storage, awaiting removal and preparation for final shipment. The damaged fuel elements were then removed from the wet storage ponds, some placed inside special sealed cans, and then deposited in the dry storage holes for long term storage. The management of spent fuel remained a very important aspect of the operation of research reactors for ANSTO. For disposition of UK-origin spent fuel arising from the operation of the HIFAR reactor, ANSTO initially elected to ship the irradiated fuel assemblies to the UKAEA in Dounreay, Scotland. With the closure of Dounreay, alternatives were evaluated, and reprocessing of the spent fuel at the La Hague reprocessing plant was selected as the option for the disposition of ANSTO’s UK origin spent fuel. Between 1999 and 2004, a total of 1288 fuel assemblies were sent in four shipments to the La Hague reprocessing plant. For the remaining HIFAR fuel assemblies containing US origin uranium, ANSTO decided to exercise its option to return the fuel assemblies to the USA under the Foreign Research Reactor Spent Nuclear Fuel (FRR SNF) acceptance programme. ANSTO’s remaining spent fuel was shipped to the USA in 2006 and 2009 respectively. This paper describes ANSTO’s management of its spent fuel inventory.
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    Preparation and performance of the largest ever shipment of irradiated HEU fuel elements under the FRR program: the 2006 ANSTO HIFAR spent fuel transport from Sydney to the United States
    (European Nuclear Society, 2007-03-11) Hart, K; Dimitrovski, L; Anderson, M; Anne, C; Adam, J
    The HIFAR reactor was officially shut down on 30 January 2007. The management of spent fuel remains a very important aspect of the operation of research reactors for Australian Nuclear Science and Technology Organisation (ANSTO). Between 1999 and 2004, a total of 1288 fuel assemblies were sent in four shipments to the La Hague reprocessing plant. For the remaining HIFAR fuel assemblies containing U.S. origin uranium, ANSTO decided to exercise its option to return the fuel assemblies to the U.S. under the Foreign Research Reactor Spent Nuclear Fuel (FRR-SNF) Acceptance program. The shipment consisted of 5 NAC-LWT casks containing 42 fuel elements each and 2 TN-7/2 casks each containing 60 fuel elements each, representing a total of 330 fuel elements. 3 types of fuel elements were part of the shipment: 2 types are cylindrical elements while the third type consists of fuel plates. The handling of large casks like NAC-LWT has required preparatory works like the availability of a reinforced concreted area. The use of NAC Dry Transfer System was necessary because the reactor pool at ANSTO is too swallow to permit a wet loading). This shipment was the largest shipment of HEU (high enrichment uranium) removed from one single facility under the FRR program. After a long maritime voyage, the 7 casks were delivered safely to the DOE site at Savannah River in South-Carolina. © The Authors
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    Radioactive waste management at ANSTO - managing current and historic wastes
    (International Atomic Energy Agency (IAEA), 2001-11-05) Harries, JR; Dimitrovski, L; Hart, KP; Levins, DM
    The Australian Nuclear Science and Technology Organisation (ANSTO) site at Lucas Heights has operated as a nuclear site for over 40 years and most of the waste generated is still stored at the site. The 10 MW heavy water research reactor (HIFAR) has operated at Lucas Heights for over 40 years with associated radioisotope and radiopharmaceutical production facilities. HIFAR is scheduled to shut down in 2005 and a contract has been signed for a multipurpose 20 MW research reactor which, amongst other uses, will provide continued radiopharmaceutical production and neutron beam research. In addition to these activities, a wide range of nuclear science and technology R and D is carried out at the site. In 1995, ANSTO issued its radioactive waste management policy which made a commitment to: (a) complying with all regulatory requirements; (b) ensuring that radiation dose rates were kept as low as reasonably achievable (the ALARA principle); (c) disposing of waste when appropriate disposal routes are available; and (d) being in accord with international best practice. An extensive audit was earned out of ANSTO's waste management facilities and practices. The recommendations arising from this audit became the basis for an integrated five year Waste Management Action Plan, which began in 1996. The Plan dealt with legacy issues that had arisen from the accumulation of the radioactive waste at Lucas Heights. It involved construction and operation of improved storage facilities for low- level radioactive waste, better monitoring of existing storage facilities for spent research reactor fuel and intermediate level liquid wastes, and conversion of liquid and solid wastes into more stable forms suitable for prolonged storage. Solidification of the intermediate level liquid waste has been a major priority of the Waste Management Action Plan. This acidic waste is generated during the production of molybdenum-99 for radiopharmaceutical use. A hot cell process was developed involving concentration of the waste by evaporation, destruction of the ammonium ion by a novel process and solidification of the waste as a uranium-rich salt. Routine processing of the liquid waste commenced in 1999 and to date over 2 m3 of liquid waste has been converted to a solid. The solidified waste is stored in high- integrity stainless steel vessels with a design life of at least 50 years. Another project under way will convert this solid waste into a more durable waste form suitable for long term storage or disposal. Two waste forms were initially considered; a titanate-based variant of synroc and cement. Laboratory scale testing established the feasibility of producing the titanate based ceramic with a high waste loading (∼44 wt % U) and the superior performance of this matrix over cement. Engineering scale development of a hot cell process for production of the ceramic waste form is under way. Much of the historic waste was characterised when it was generated by external dose with little information recorded about the radionuclide content. In 1996, a radioactive waste scanning system was installed to determine the radionuclide content of drums of historic waste. A data base system is being developed to integrate the characterisation, treatment and location information on the radioactive waste at ANSTO including the results from the drum scanning measurements. An important objective of ANSTO's waste management policy is minimization of radioactive waste generated and stored. This is being achieved by a number of strategies: for example, in one radioisotope production area a threefold reduction in waste volume has been achieved by separating non-radioactive waste from radioactive waste at the source. A substantial reduction in radioactive gas emissions during the production of molybdenum-99 has also been achieved by changes in waste processing operations and procedures. As well as focussing on historical waste issues a number of initiatives within ANSTO aimed at improving current processes and waste systems are being carried out. Currently, waste water from active drains at ANSTO is treated by a flocculation/centrifugation process and discharged to the sewer. Over the next few years, ANSTO plans to upgrade its effluent treatment facilities using state-of-the-art technology. Pilot plant demonstration of a membrane-based process is in progress after which a specification will be prepared for a full scale plant. Planning is also under way for a new facility to treat and package ANSTO's radioactive waste in readiness for disposal in the national repository for low level and short lived intermediate level waste. © Author(s) 2001
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    The return of Australia's intermediate level waste from France
    (Australiasian Radiation Protection Society, 2012-10-16) Dimitrovski, L; Donlevy, TM
    On 1 May 2012, the Australian Nuclear Science and Technology Organisation announced that it will apply for a licence to construct an interim storage facility for Australian radioactive waste generated by several decades of nuclear medicine production and scientific research. Plans for the proposed interim storage facility will be assessed by the independent regulator, the Australian Radiation Protection and Nuclear safety Agency, ARPANSA, which will conduct a public consultation process. The proposed new storage facility at Lucas Heights (subject to regulatory approval) would enable Australia to meet obligations to repatriate Australian waste currently being reprocessed in France and due, under arrangements established by Governments in the 1990s, to return to Australia by the end of 2015. It is anticipated that this proposed interim facility would operate at Lucas Heights for up to five years from late 2015 - while planning is underway for the siting, design and construction of a national radioactive waste management facility anticipated to be operational by 2020. This talk will summarise the history of ANSTO's spent fuel management and past shipments to the USA, UK and France, focus on the intermediate level waste arising from reprocessing in France and the specially designed package it will be transported and stored in; and, expand on the plans underway at ANSTO to enable it to receive and manage this waste by the agreed deadline in 2015.