Scientific and Technical Reports

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Report on the proceedings of a symposium on nuclear ships
(Australian Atomic Energy Commission, 1971-10-18) Higson, DJ
To some extent the Hamburg Symposium on Nuclear Ship? was disappointing in that no major technical advances were reported and no new projects or plans for the application of nuclear propulsion to commercial shipping were announced. In fact, a number of papers tended to be a rehash of ideas which have been current for the past ten years, without throwing any new light on the problems. This was particularly notable in the regulatory area. Since the formulation in 1962 of the Brussels Convention on the Liability of Operators of Nuclear Ships, there has been very little real progress towards the acceptance of unrestricted operation by commercial nuclear powered vessels. However, technical development has been proceeding steadily and an advance towards commercial exploitation has become evident. Some important trends, such as an, increasing interest amongst shipowners, were also "apparent at the Symposium. In terms of actual industrial activity West Germany is now the leader in this field and dominated the proceedings. The research vessel "Otto Hahn" has been in service since 1968 and has carried commercial cargoes. This ship is operated by the Gesellschaft' fur -Kernenergieverwertung in Shiffbau und Schiffahrt mbH (GKSS) which is a government controlled corporation through which industry collaborates in government backed design, research and development work. Japan and Italy are also active and the first Japanese nuclear powered ship, the "Mutsu", is being fitted out at present for commissioning in 1973. The USA confined its contributions to the Symposium mainly to reporting experience with the NS "Savannah", which is now laid up. Only one paper (presented by Vickers Shipbuilding) originated from the UK. However, the US and UK Governments, though not currently optimistic about the commercial prospects for nuclear propulsion, have the technical and industrial backing to enter this field at short notice if the business becomes attractive. Economically the position is fairly clear although strongly dependent upon the cost of bunkering oil fuel for conventional shipping. Oil costs are very high at present and, assuming the continuation of this situation, it appears that large nuclear powered container ships of 120,000 shp and 30 knot service speed would be competitive in operation between Australia and Europe and probably also on shorter runs (e.g., the Pacific trade). Once established, it should then be possible for nuclear propulsion to be applied economically to other types of shipping and to smaller power units. A return to the low prices for fuel oil which prevailed in 1969 would probably make nuclear propulsion totally uneconomic however. In any case, significant governmental support would be an essential investment in t .... rly stages. Generally there can be no doubt concerning the ability of nuclear marine propulsion to provide a reliable service with the characteristic of sustained high power which could not be obtained in any other way but questions of legal liability, indemnification and international acceptance remain to be resolved. In some related respects the technical status of nuclear propulsion is not entirely satisfactory. A number of safety problems have not yet been convincingly solved and these matters will require careful evaluation by regulatory authorities. There could well be a need for the feedback of views to the designers. This will become an urgent problem if commercial exploitation proceeds at the rate which some authorities predict, and pressure is already growing for a reduction of restrictions upon the operation of nuclear ships.
Uranium mining industry review 1971/72
(Australian Atomic Energy Commission, 1972) South, SA
This is the second report in the series "Uranium Mining Industry Review" based on information received by the Nuclear Materials Section. Unless other-wise stated, costs shown are in US dollars
Transport of radioactive materials
(Australian Nuclear Science and Technolgy Organisation, 1990-09) Rolland, JM
It is estimated that around 500 million packages of potentially hazardous materials are transported throughout the world each year. This range of materials includes corrosives, flammable gases, flammable liquids, poisons, oxidisers and explosives. Our everyday life depends on the routine transport of these materials and we intuitively accept the small risk associated with their distribution. Radioactive materials represent one other type of potentially hazardous material. Several tens of millions of packages of radioactive material are transported throughout the world annually. Around 90% of these packages contain only small quantities of radioisotopes, mainly for medical purposes. Most of the remaining 10% contain radioisotopes for industrial and research purposes. Shipments of nuclear fuel cycle materials represent only a few percent of the radioactive packages transported. The number of shipments of radioactive materials will continue to increase by about 10% each year as the medical, industrial and research uses of radioisotopes are more widely applied as a nuclear fuel cycle activities increase. About 50,000 packages of radioactive materials are transported annually within Australia. Of this number, Ansto ships over 20,000 packages each year to all main cities in Australia and to regional countries. The vast majority of these shipments constitute radiopharmaceuticals for medical diagnostic purposes. About 75% of the shipments made by Ansto are by air and 25% by road to destinations within the Sydney area.
The environmental behaviour of uranium
(International Atomic Energy Agency, 2023) Carvalho, FP; Fesenko, S; Harbottle, AR; Lavrova, T; Mitchell, NG; Payne, TE; Rigol, A; Thorne, MC; Ulanowski, A; Vidal, M; Voitsekhovych, O; West, JM; Yankovich, TL
This publication is one of the series of IAEA publications on the environmental behaviour of naturally occurring radionuclides It outlines uranium behaviour in different environments, as well as its transfer to, and metabolism in, humans The publication also provides concepts, models and data required for the assessment of the impacts of uranium on non-human biota Assessing the environmental and health effects of uranium poses specific challenges because of the combination of different types of hazard and potential exposures Therefore, both the radiotoxicity and chemical toxicity of uranium are considered in this publication.
Interim report task 2: performance testing- task 2.4: natural mineral analog studies performance and chemical characteristics of brannerite in natural systems to Lawrence Livermore National Laboratory for Contract B345772
(US Department of Energy (DOE), 2000-04-30) Lumpkin, GR; Colella, M; Leung SHF
To investigate the long-term alteration behavior of brannerite, we have undertaken a study of 13 natural samples from various geological environments, including granites, granitic pegmatites, quartz veins, and placer deposits. Literature data and U-Th-Pb chemical dating carried out in this work indicate that the samples range in age from approximately 20 Ma to 1580 Ma. Where independent age data or estimates are available for comparison, the U-Th-Pb chemical ages are in reasonable agreement for the younger samples, but the older samples tend to show evidence for Pb loss (up to about 80%), a common feature of metamict Nb, Ta, and Ti oxide minerals. Our results show that many of the samples exhibit only minor alteration, usually within small patches, microfractures, or around the rims of the brannerite crystals. Other samples consist of variable amounts of unaltered and altered brannerite. Heavily altered samples may contain anatase and thorite as fine-grained alteration products. Certain samples exhibited fracturing of the associated rock matrix or mineral phase in the immediate vicinity of the brannerite grains. These fractures contain U bearing material and indicate that some U migrated locally from the source brannerite.

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