High-Level Nuclear Waste

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High Level Nuclear Waste Repository Thermal Loading Analysis

High Level Nuclear Waste Repository Thermal Loading Analysis

The Nuclear Waste Policy Act of 1982 1 , as amended, sets the statutory limit of the proposed Yucca Mountain Nuclear Waste Repository at 63,000 metric tons initially heavy metal (MTIHM) of commercial spent nuclear fuel (SNF). It also requires that between 2007 and 2010 the Secretary of Energy report to the President on the need for a second U.S. High Level Nuclear Waste (HLW) repository. Given the high economic, social, and political costs associated with the siting of a HLW repository, investigating the expansion of the proposed Yucca Mountain statutory limit to beyond 63,000 MTIHM, rather than siting a second repository, is of significant interest. The factor that limits the amount of SNF that can safely be emplaced per unit area in a geologic repository is not the volume of the SNF, but rather the decay heat of the SNF in conjunction with the thermal loading scenario chosen for the geologic repository. The decay heat emanating from SNF is a function of the fuel burn-up, average power, initial enrichment, and cooling period.
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Disposal of High-Level Nuclear Waste in Deep Horizontal Drillholes

Disposal of High-Level Nuclear Waste in Deep Horizontal Drillholes

Abstract: Spent nuclear fuel and high-level radioactive waste can be disposed in deep horizontal 14.. drillholes in sedimentary, metamorphic, or igneous rocks.[r]

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Radionuclide migration in plutonic rocks: implications for high level nuclear waste disposal

Radionuclide migration in plutonic rocks: implications for high level nuclear waste disposal

Chapter 8: Simulation of Repository Processes II: The Interaction of Granite and Synroc doped with Mixed Fission Products 8.1 Introduction - Previous Work 8.2 Mixed Fission Products.. 8.[r]

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Radionuclide migration in plutonic rocks: implications for high level nuclear waste disposal

Radionuclide migration in plutonic rocks: implications for high level nuclear waste disposal

Interaction between the migrating ground waters and the rock has been influeneed by the presence offracture·infilling and other secondary minerals, As an analogue for the behaviour o'f t[r]

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Radionuclide migration in plutonic rocks: implications for high level nuclear waste disposal

Radionuclide migration in plutonic rocks: implications for high level nuclear waste disposal

Interaction between the migrating ground waters and the rock has been influeneed by the presence offracture-infilling and other secondary minerals, As an analogue for the behaviour of th[r]

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Radionuclide migration in plutonic rocks: implications for high level nuclear waste disposal

Radionuclide migration in plutonic rocks: implications for high level nuclear waste disposal

8.5 Conclusions The leach testing in deionised water of the Coles Bay Granite, Roxby Downs Granite and the Kambalda Granodiorite with Synroc doped with the mixed fission products under s[r]

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Canada's High-Level Nuclear Waste Disposal Concept: The Evaluation Process and a Review of Some Aspects of the Research Work

Canada's High-Level Nuclear Waste Disposal Concept: The Evaluation Process and a Review of Some Aspects of the Research Work

OCflce SAT - Subsurface Advisory Team (Environment Canada.) SRG - Scientific Review Group (FEARO) TAC - Technical AdvIsory Committee (AECI.) Figure 1: Evaluation of Canadian Nuclear Wast[r]

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Crystallization behavior of iron  and boron containing nepheline (Na2 O●Al2 O3 ●2SiO2 ) based model high level nuclear waste glasses

Crystallization behavior of iron and boron containing nepheline (Na2 O●Al2 O3 ●2SiO2 ) based model high level nuclear waste glasses

Magnetic measurements, owing to their non-destructive nature and high sensitivity towards iron-containing phases, are a rapid characterization technique to obtain valuable information about distribution of Fe in different phases present in the sample. 23 Therefore, magnetic measurements were performed on isothermally produced glass-ceramics using a vibrating sample magnetometer (VSM, PMC3900, Lakeshore Cryotronics, Westerville, OH). Magnetic hysteresis loops of the samples isothermally heat-treated in different environment were collected at maximum applied field of 1.8 T using field increments of 2 mT. The first order reversal curves (FORCs) 37 data of the same samples were also obtained with a field increment of 6 mT, and processed employing FORCinel software (V2.05 in IGOR Pro6, WaveMetrics, Portland, OR). 38
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Harmless Disposal Techniques of Radioactive Nuclear Wastes - A Review Anil R. Saradva

Harmless Disposal Techniques of Radioactive Nuclear Wastes - A Review Anil R. Saradva

(2) Intermediate-level waste: Intermediate-level waste emits higher levels of radiation and requires additional shielding during handling, transport and storage. They consist of different types and activities of wastes, usually from the reactor cycle: process filters ion exchange resins, chemical sludge’s, and materials with generally greater radioactive contamination and associated dose rates. They also may include used industrial and medical devices and related isotopes. Which are not easily contained or packaged, can be stored in steel drums - perhaps filled with high density shielding and stabilizing materials such as sand, concrete or bitumen - before being placed into surface storage facilities for management and monitoring.
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High Level Nuclear Wastes and the Environment: Analyses of Challenges and Engineering Strategies

High Level Nuclear Wastes and the Environment: Analyses of Challenges and Engineering Strategies

Geological disposal of SNF can only be successful by implementing multiple barrier strategy to confine the disposed waste and its effects far from safe environment to which living being have or may need to have contact in future. Figure 5(a) gives an overview of possible bar- riers to confine the disposed high level waste. Most im- portant of natural barriers is a solid stable crystalline rock far from earth quake related fault lines. Engineered bar- riers include corrosion-resistant containers possibly of copper alloys and disposal architecture. Recently, a new method has proposed by Rana [17] for monitoring the radiation damage in nuclear waste containers using ion channeling. Ion channeling measurements are possible at ion beam facilities worldwide. A 1 - 3 MeV helium ion beam can be employed to measure radiation damage in test crystalline samples placed in a section of a container wall as shown in Figure 5(b). Mathematical method for determination of structure collapse rate in container wall using ion channeling measurements is given by Rana ([17] 2008a). This method can be used to monitor the radiation damage in nuclear waste containers and to pre- dict containment failures in near and far-future. Nature of single radiation damage in bulk and surface-layer of a typical solid is recently discussed by Rana [17,18]. Total radiation damage is accumulated effect of all radiations penetrated in to a target or containment materials, with different radiations causing different magnitude and type of damage. Thermal and chemical stability [19,21] of containment materials is an important in selection of ma- terials to be used in containment of nuclear wastes.
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Ageing management program for the Spanish low and intermediate level waste disposal and spent fuel and high-level waste centralised storage facilities

Ageing management program for the Spanish low and intermediate level waste disposal and spent fuel and high-level waste centralised storage facilities

Spain has eight power reactors in operation with a total capacity of 8.3 GWe. All power plants fuel ponds have been re-racked to increase their storage capacity. Furthermore, two nuclear power plants are closed down and are in different ages of the decommissioning process. Vandellós I gas cooled reactor is now in latency period after finishing stage 1 of the decommissioning operations (all the station, except the reactor vessel, which remains sealed in safe storage condition). Its spent fuel was sent to France for reprocessing, and, eventually, some high and medium-level waste should be sent back to Spain. The Jose Cabrera PWR is being dismantled, its pool was defueled in 2009 and its spent fuel (300 t of uranium) is dry-stored in multipurpose canisters on site. The total planned spent fuel inventory in the country is around 6700 tones of uranium. Moreover, some 69 canisters of high-level vitrified waste and some 650 cubic meters of long-lived medium-level waste packages of different types should also be stored in the same facility. Low and Intermediate Level Waste (LILW) are defined as the ones complying with the El Cabril disposal facility, in operation since 1992.
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The Management of Used (Spent) Fuel and High Level Waste in South Africa

The Management of Used (Spent) Fuel and High Level Waste in South Africa

Abstract As a country with a nuclear power program and radioisotope production facility, the Republic of South Africa (RSA) generates Used Nuclear Fuel (UNF) and radioactive waste through numerous activities. The cornerstone of South Africa’s approach to addressing radioactive waste management is the Radioactive Waste Management Policy and Strategy for the Republic of South Africa. The Policy and Strategy serves as a national commitment to address radioactive waste management in a coordinated and cooperative manner and represents a comprehensive radioactive waste governance framework by formulating, in addition to nuclear and other applicable legislation, a policy and implementation strategy developed in consultation with all stakeholders. In accordance with the Policy and Strategy, final disposal is regarded as the ultimate step in the radioactive waste management process, although a stepwise waste management process is acceptable. Long-term storage of specific types of waste, such as High-Level Waste (HLW), long-lived waste and high activity disused radioactive sources, may be regarded as one of the steps in the management process. This paper presents the South African National Radioactive Waste Management Model with a description of: The radioactive waste management governance framework; the current HLW and UNF management, the management option and UNF strategies. Also the paper addresses consideration of the lessons learnt from the Fukushima accident and its impact on future radioactive waste management strategies and options, plans related to possible long term operation of the existing nuclear power plants, introduction of new nuclear power plants and public acceptance and challenges from anti-nuclear groups .
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The effect of organic retarders on grout thickening and setting during deep borehole disposal of high-level radioactive waste

The effect of organic retarders on grout thickening and setting during deep borehole disposal of high-level radioactive waste

Advantages associated with safety, cost, and ease of imple- mentation, and the ability to drill deeper larger diameter holes (Juhlin and Sandstedt, 1989; Beswick, 2008; Beswick and Forrest, 1982; Exxon Neftegas; Sakhalin-, 2013), means that the use of deep boreholes to dispose of high level radioactive wastes (HLW, including spent nuclear fuel (SF)) is now being increasingly seen as a viable alternative to emplacement in geologically shallow, mined repositories (Chapman and Gibb, 2003; Beswick et al., 2014). The disposal of wastes generated during the production of nuclear en- ergy is of significant importance to the overall nuclear fuel cycle and is currently receiving particular attention around the world. Even though considerable research has been performed in devel- oping waste repositories several hundreds of meters below ground, there is currently no operational facility to provide ultimate waste disposal. Therefore, the development of an alternative more ad- vantageous concept for the disposal of HLW is of particular interest to those involved in the nuclear fuel cycle.
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Thermal Loading and Uncertainty Analysis of High Level Waste in Yucca Mountain

Thermal Loading and Uncertainty Analysis of High Level Waste in Yucca Mountain

Assuming that the loaded spent fuel casks are directly disposed of at the Yucca Mountain, understanding how different cask loading schemes might affect the repository thermal design limits was of interest. COBRA-SFS was used to analyze the effect of nonuniform loading of spent nuclear fuels into the casks with respect to the peak clad temperature limit of 350˚C. Four different loading cases were analyzed for ambient temperatures of 17.2˚C and 200˚C on the outside of the cask. Results indicated that there is no concern with respect to the cladding surface temperature with the use of non-uniform loading of SNF in the cask over the range of SNF burnup, storage period, irradiation time and enrichment tested.
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Properties of a Multilayer Coating for Applications in High Level Waste Packaging

Properties of a Multilayer Coating for Applications in High Level Waste Packaging

Spent fuel from commercial energy producers is destined for a final deep geological disposal by the Federal Government’s Department of Energy (DOE). In 1982 the Nuclear Waste Policy Act (NWPA) was passed by Congress, which was a compromise among industry, government, and environmentalists outlining the timeline for the DOE to ultimately dispose of HLW/SNF geologically (from this point forward, SNF will be combined into the term HLW unless specifically addressing aspects of SNF). Since the NWPA was passed, power generators have been charging a fee of one-tenth of a cent for each kilowatt-hour to help DOE pay for the research and development of a site for disposal. Also, as a result of the NWPA, a new office for addressing this task was set up in the DOE, the Office of Civilian Radioactive Waste Management (OCRWM). This office started out by studying various locations as possible sites for the geological HLW disposal. The site possibilities were narrowed down to three by 1987, including Deaf Smith County, Texas, Hanford, Washington, and Yucca Mountain, Nevada. At this time, Congress amended the NWPA, which declared Yucca Mountain as the only site that would be further investigated by DOE for geological disposal. Since 1987, the OCRWM has been characterizing and studying aspects of HLW disposal at Yucca Mountain including geology, hydrology, seismology, volcanology, meteorology, ecology, as well as social aspects such as law, sociology, demography, and politics.
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Autonomous nuclear waste management

Autonomous nuclear waste management

Abstract—Redundant and non-operational buildings at nuclear sites are decommissioned over a period of time. The process involves de- molition of physical infrastructure resulting in large quantities of residual waste material. The resulting waste materials are packed into import containers to be delivered for post-processing, containing either sealed canisters or assortments of miscellaneous objects. At present post- processing does not happen within the United Kingdom. Sellafield Ltd. and National Nuclear Laboratory are developing a process for future operation so that upon an initial inspection, imported waste materials undergo two stages of post-processing before being packed into export containers, namely sort and segregate or sort and disrupt. The post- processing facility will remotely treat and export a wide range of wastes before downstream encapsulation. Certain wastes require additional treatment, such as disruption, before export to ensure suitability for long-term disposal. This article focuses on the design, development, and demonstration of a reconfigurable rational agent-based robotic sys- tem that aims to highly automate these processes removing the need for close human supervision. The proposed system is being demon- strated through a downsized, lab-based setup incorporating a small- scale robotic arm, a time-of-flight camera, and high-level rational agent- based decision making and control framework.
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EVOLUTION OF ROBOTICS IN NUCLEAR REACTOR AND NUCLEAR WASTE HANDLING

EVOLUTION OF ROBOTICS IN NUCLEAR REACTOR AND NUCLEAR WASTE HANDLING

The waste residue of products and by products of the reactions in the reactor, the fuel rods and the remnants of the old machines or other materials inside the reactor in combination can be called as nuclear waste which is hazardous and has to be handled carefully. A fast and versatile tool for situation assessment is needed without putting personnel at risk. In such situations certain general-purpose robots for these jobs are incorporated like the Remotec ANDROS or Rovtech Scarab. [6] For a long time, the manipulation of hazardous material has been executed by a master/slave system. The operator manipulates a master arm that is mechanically connected to a slave robot in a hot cell. The robot reproduces every movement of the operator. For radioactive environments, the requirements for tele operated robots are a good sealing of the parts to avoid contamination, the installation of a force feedback system, an acceptable level of radiation hardness, a good payload/mass ratio, a high reliability and modularity for easier maintenance and an easy integration into embedded equipment. The installation of a radiation-hardened force feedback system is very important when upgrading a commercial manipulator to its 29 nuclear equivalent. [6]
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Radiation effects in glasses used for immobilization of high-level waste and plutonium disposition

Radiation effects in glasses used for immobilization of high-level waste and plutonium disposition

Borosilicate glass is, at present, the waste form of choice for most nuclear waste compositions and for most countries (e.g., France, Great Britain, the United States, Japan, and China) that have high-level defense waste or high-level waste from reprocessing of commercial nuclear fuels. The selection of borosilicate glass was based mainly on four assumptions: (i) an anticipated ease of processing (glass frit and the waste are mixed, melted at relatively low temperatures, and poured into canisters); (ii) that the technology is well demonstrated for actual (radioactive) waste; (iii) that the glass as an aperiodic solid will easily accommodate wide variations in waste stream compositions which are extremely complex (20 to 30 component systems); and finally, (iv) that glass as an aperiodic solid will show only a minor response to the effects of radiation, especially from a-decay events. Glass waste forms can be of a wide variety of com- positions, including silicate glasses, borosilicate glasses, and phosphate glasses. 35 In principle, radionuclides are
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Geological disposal of nuclear waste: A primer

Geological disposal of nuclear waste: A primer

Engineered barriers include the waste form, the waste package, and the surrounding backfill. Most of the engineered barriers are physical in that they delay the access of water to the waste package (e.g. the Ti-drip shields proposed at Yucca Mountain, Nevada, USA) or they delay the release of radionuclides from a breached canister (e.g. the bentonite buffer in the KBS-3 concept for granite repositories [see Hedin and Olsson 2016 this issue]). In some cases, the engineered barrier has a chemical function, affecting the geochemical environment around the waste. For example, MgO is emplaced with the transuranic waste in the bedded salt repository at the Waste Isolation Pilot Plant (WIPP) in New Mexico, and high-pH cement was developed in the UK to encapsulate intermediate-level waste. In both cases, the intention is to remove CO 2 and provide an environment in which the solubility of
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Corrosion susceptibility of steel drums to be used as containers for intermediate level nuclear waste

Corrosion susceptibility of steel drums to be used as containers for intermediate level nuclear waste

When applying the results obtained in the present work to estimate the corrosion depth of the steel drums containing the cemented radioactive waste after a period of 300 years, it is found that in the most unfavourable case (high chloride contamination), the corrosion penetration will be considerably lower than the thickness of the wall of the steel drums. Thus, cementation of ion-exchange resins seems not to pose special risks regarding the corrosion of the steel drums that contained them; even in the case the matrix is highly contaminated with chloride ions.

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