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At least 775 records · Page 43

Localized Imaging and Mapping for Underwater Fuel Storage Basins - 18364

Current methods for inspection of spent nuclear fuel storage basins involve lowering a single camera for visual inspection of walls and other structures. We present a localized inspection solution where the images are automatically annotated by localization information and a 3D model of the inspected area is generated. The system consists of an underwater sensor pod containing a stereo pair of cameras, light source, inertial measurement unit, and a pressure sensor. The sensors are time synchronized to provide precise measurements. We describe both the sensor pod and the algorithms that keep the pod localized. Preliminary results from in-air testing of a prototype are presented. (authors)

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RHENIUM SOLUBILITY IN BOROSILICATE NUCLEAR WASTE GLASS IMPLICATIONS FOR THE PROCESSING AND IMMOBILIZATION OF TECHNETIUM-99 (AND SUPPORTING INFORMATION WITH GRAPHICAL ABSTRACT)

The immobilization of 99Tc in a suitable host matrix has proved a challenging task for researchers in the nuclear waste community around the world. At the Hanford site in Washington State in the U.S., the total amount of 99Tc in low-activity waste (LAW) is {approx} 1,300 kg and the current strategy is to immobilize the 99Tc in borosilicate glass with vitrification. In this context, the present article reports on the solubility and retention of rhenium, a nonradioactive surrogate for 99Tc, in a LAW sodium borosilicate glass. Due to the radioactive nature of technetium, rhenium was chosen as a simulant because of previously established similarities in ionic radii and other chemical aspects. The glasses containing target Re concentrations varying from 0 to10,000 ppm by mass were synthesized in vacuum-sealed quartz ampoules to minimize the loss of Re by volatilization during melting at 1000 DC. The rhenium was found to be present predominantly as Re7 + in all the glasses as observed by X-ray absorption near-edge structure (XANES). The solubility of Re in borosilicate glasses was determined to be {approx}3,000 ppm (by mass) using inductively coupled plasma-optical emission spectroscopy (ICP-OES). At higher rhenium concentrations, some additional material was retained in the glasses in the form of alkali perrhenate crystalline inclusions detected by X-ray diffraction (XRD) and laser ablation-ICP mass spectrometry (LA-ICP-MS). Assuming justifiably substantial similarities between Re7 + and Tc 7+ behavior in this glass system, these results implied that the processing and immobilization of 99Tc from radioactive wastes should not be limited by the solubility of 99Tc in borosilicate LAW glasses.

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On-Site Pilot Study - Removal of Uranium, Radium-226 and Arsenic from Impacted Leachate by Reverse Osmosis - 13155

Conestoga-Rovers and Associates (CRA-LTD) performed an on-site pilot study at the Welcome Waste Management Facility in Port Hope, Ontario, Canada, to evaluate the effectiveness of a unique leachate treatment process for the removal of radioactive contaminants from leachate impacted by low-level radioactive waste. Results from the study also provided the parameters needed for the design of the CRA-LTD full scale leachate treatment process design. The final effluent water quality discharged from the process to meet the local surface water discharge criteria. A statistical software package was utilized to obtain the analysis of variance (ANOVA) for the results from design of experiment applied to determine the effect of the evaluated factors on the measured responses. The factors considered in the study were: percent of reverse osmosis permeate water recovery, influent coagulant dosage, and influent total dissolved solids (TDS) dosage. The measured responses evaluated were: operating time, average specific flux, and rejection of radioactive contaminants along with other elements. The ANOVA for the design of experiment results revealed that the operating time is affected by the percent water recovery to be achieved and the flocculant dosage over the range studied. The average specific flux and rejection for the radioactive contaminants were not affected by the factors evaluated over the range studied. The 3 month long on-site pilot testing on the impacted leachate revealed that the CRA-LTD leachate treatment process was robust and produced an effluent water quality that met the surface water discharge criteria mandated by the Canadian Nuclear Safety Commission and the local municipality. (authors)

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Waste Treatment Plant - 12508

The Waste Treatment Plant (WTP) will immobilize millions of gallons of Hanford's tank waste into solid glass using a proven technology called vitrification. The vitrification process will turn the waste into a stable glass form that is safe for long-term storage. Our discussion of the WTP will include a description of the ongoing design and construction of this large, complex, first-of-a-kind project. The concept for the operation of the WTP is to separate high-level and low-activity waste fractions, and immobilize those fractions in glass using vitrification. The WTP includes four major nuclear facilities and various support facilities. Waste from the Tank Farms is first pumped to the Pretreatment Facility at the WTP through an underground pipe-in-pipe system. When construction is complete, the Pretreatment Facility will be 12 stories high, 540 feet long and 215 feet wide, making it the largest of the four major nuclear facilities that compose the WTP. The total size of this facility will be more than 490,000 square feet. More than 8.2 million craft hours are required to construct this facility. Currently, the Pretreatment Facility is 51 percent complete. At the Pretreatment Facility the waste is pumped to the interior waste feed receipt vessels. Each of these four vessels is 55-feet tall and has a 375,000 gallon capacity, which makes them the largest vessels inside the Pretreatment Facility. These vessels contain a series of internal pulse-jet mixers to keep incoming waste properly mixed. The vessels are inside the black-cell areas, completely enclosed behind thick steel-laced, high strength concrete walls. The black cells are designed to be maintenance free with no moving parts. Once hot operations commence the black-cell area will be inaccessible. Surrounded by black cells, is the 'hot cell canyon'. The hot cell contains all the moving and replaceable components to remove solids and extract liquids. In this area, there is ultrafiltration equipment, cesium-ion exchange columns, evaporator boilers and recirculation pumps, and various mechanical process pumps for transferring process fluids. During the first phase of pretreatment, the waste will be concentrated using an evaporation process. Solids will be filtered out, and the remaining soluble, highly radioactive isotopes will be removed using an ion-exchange process. The high-level solids will be sent to the High-Level Waste (HLW) Vitrification Facility, and the low activity liquids will be sent to the Low-Activity Waste (LAW) Vitrification Facility for further processing. The high-level waste will be transferred via underground pipes to the HLW Facility from the Pretreatment Facility. The waste first arrives at the wet cell, which rests inside a black-cell area. The pretreated waste is transferred through shielded pipes into a series of melter preparation and feed vessels before reaching the melters. Liquids from various facility processes also return to the wet cell for interim storage before recycling back to the Pretreatment Facility. (authors)

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Cask RT-100 Type B(U) Self-Certification for DOT 7A, Type A Nuclear Waste Transportation - 20098

The purpose of this Type A certification is to diversify the use of the RT-100 cask by allowing the end user to transport either Type A or Type B radioactive waste in accordance with the handling procedures for each waste category. The project's scope included the development of a matrix that contains all applicable requirements for a Type A package from the Code of Federal Regulations (CFR), Title 49 for the Department of Transportation (DOT) with a justification for each requirement. Moreover, the scope included the writing of conditions and restrictions list for the transportation of Type A nuclear waste, the writing of a compliance statement, and the design and fabrication of a Type A placard to be permanently placed on the RT-100 cask. Type A packages are self-certified by the end user using one of three methods as permitted by 49 CFR 173.461, either by performance of tests with prototypes or samples of the specimens representing the packaging, or reference to a previous satisfactory demonstration of compliance of a sufficiently similar nature, or calculations or reasoned evaluation using reliable and conservative procedures and parameters. Since the RT-100 cask was licensed by the Nuclear Regulatory Commission (NRC) as a Type B cask, Robatel relied on the method of reference to a previous satisfactory demonstration of compliance of a sufficiently similar nature for Type A certification. This method was determined to be acceptable, since Type B packages are evaluated for more demanding transport conditions than those required for Type A packages. This paper presents Robatel's process for certifying the RT-100 cask for Type A shipments, an overview of the DOT regulations related to Type A packages, and the documents that were generated for the end user. This paper is concluded with a discussion on the advantages of having the option to transport both Type A and Type B nuclear waste, and possible future projects to further improve the operation of the cask when making Type A shipments. (authors)

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Defense Waste Processing Facility (DWPF) Durability-Composition Models and the Applicability of the Associated Reduction of Constraints (ROC) Criteria for High TiO 2 Containing Glasses

Radioactive high-level waste (HLW) at the Savannah River Site (SRS) has successfully been vitrified into borosilicate glass in the DWPF since 1996. Vitrification requires stringent product/process (P/P) constraints since the glass cannot be reworked once it has been poured into ten foot tall by two foot diameter canisters. A unique “feed forward” statistical process control (SPC) was developed for this control rather than relying on statistical quality control (SQC). In SPC, the feed composition to the DWPF melter is controlled prior to vitrification. In SQC, the glass product would be sampled after it is vitrified. Individual glass property-composition models form the basis for the “feed forward” SPC. The models transform constraints on the melt and glass properties into constraints on the feed composition going to the melter in order to determine, at the 95% confidence level, that the feed will be processable and that the durability of the resulting waste form will be acceptable to a geologic repository. The DWPF SPC system is known as the Product Composition Control System (PCCS). One of the process models within PCCS is known as the Thermodynamic Hydration Energy Reaction MOdel (THERMO™). The DWPF will soon be receiving increased concentrations of TiO 2 -, Na 2 O-, and Cs 2 O-enriched wastes from the Salt Waste Processing Facility (SWPF). The SWPF has been built to pretreat the high-curie fraction of the salt waste to be removed from the HLW tanks in the F- and H-Area Tank Farms at the SRS. In order to validate the existing TiO 2 term in THERMO™ beyond 2.0 wt% in the DWPF, new durability data were developed over the target range of 2.00 to 6.00 wt% TiO 2 and evaluated against the 1995 durability model. The durability was measured by the 7-day Product Consistency Test. This study documents the adequacy of the existing THERMO™ terms. It is recommended that the modified THERMO™ durability models and the modified property acceptable region limits for the durability constraints be incorporated in the next revision of the technical bases for PCCS and then implemented into PCCS. It is also recommended that an reduction of constraints of 4 wt% Al 2 O 3 be implemented with no restrictions on the amount of alkali in the glass for TiO 2 values ≥2 wt%. The ultimate limit on the amount of TiO 2 that can be accommodated from SWPF will be determined by the three PCCS models, the waste composition of a given sludge batch, the waste loading of the sludge batch, and the frit used for vitrification.

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Electrical Resistivity Changes During Heating Experiments Unravel Heterogeneous Thermal‐Hydrological‐Mechanical Processes in Salt Formations

Abstract Rock salt is considered a suitable medium for the permanent disposal of heat‐generating radioactive waste due to its isolation properties. However, excavation damage and heating induce complex and heterogeneous thermal‐hydrological‐mechanical (THM) processes across different zones. Quantifying this heterogeneity is crucial for accurate long‐term performance assessment models, but traditional methods lack the necessary resolution. This study employs 4D electrical resistivity tomography (ERT) monitoring during controlled heating experiments in a salt formation to unravel the spatiotemporal dynamics of THM processes. Advanced time‐lapse inversion and clustering analysis quantify subsurface properties and map the heterogeneity of THM dynamics. The ERT results can estimate subsurface properties and delineate the damaged and intact zones, enabling appropriate parameterization and representation of processes for long‐term modeling. This approach may be used in further improving the predictive models and ensuring the safe long‐term disposal of radioactive waste in rock salt.

58 GEOSCIENCES↗

Adsorption and Transport Properties of Zeolite SAPO-34 for Krypton/Xenon Separations

Nuclear power is an economical means of providing carbon-free energy, but requires effective ways to deal with the radioactive waste products. As part of the overall process for recycling used nuclear fuel (UNF), it is necessary to develop technologies to separate the off-gases formed during the fission of uranium and plutonium in nuclear power reactors. The off-gas contains {sup 129}I (radioisotope), NO, NO{sub 2}, CO{sub 2} containing {sup 14}C (radioisotope), {sup 3}H{sub 2}O (radioactive tritium oxide), {sup 85}Kr (radioisotope), and {sup 136}Xe. Separating and capturing each gas is essential to reduce the volume of radioactive waste for storage. Currently there exist economical technologies to separate {sup 129}I and {sup 14}CO{sub 2}. However, Kr and Xe separation is challenging because they are chemically inert and physically very similar. The Kr/Xe mixture is approximately 10/90 by volume and hence the separation of Kr would reduce the volume of radioactive {sup 85}Kr waste by a factor of 10. One way of separating them is by cryogenic distillation wherein they are condensed out as pure streams at very low temperature (Kr boiling point: -153 deg. C, Xe: -108 deg. C). Cryogenic distillation has intensive power requirements and a large system volume, resulting in high capital, operating, and disposal costs. Membrane-based separation using radiation-stable materials such as nanoporous zeolites is an attractive alternative, if membranes with sufficient Kr flux and selectivity can be fabricated. An ideal membrane process would permeate a stream of pure Kr for storage and also produce a retentate of pure Xe which has commercial value (> $8/g at 99+% purity from Airgas{sup R}). Zeolites are nanoporous crystalline aluminosilicate materials with pores that are capable of separating molecules by shape and size. SAPO-34 is a silicoaluminophosphate zeolite with pore size of 0.38 nm. The SAPO-34 is a molecular sieve composed of 3D networks with CHA frame structure containing uniform micropores. Since this pore size is intermediate between the kinetic diameters of krypton (0.36 nm) and xenon (0.396 nm), it was hypothesized that SAPO-34 membranes can separate krypton and xenon by diffusivity differences. Previously we fabricated SAPO-34 membranes and showed that they are capable of separating Kr from Xe. Here we describe a more detailed study of the fundamental adsorption and transport properties of SAPO34. In particular, the permeabilities of Kr and Xe in SAPO-34 are dependent on both their adsorption and diffusion characteristics in the nanoporous zeolite. Typically, nanoporous materials show stronger adsorption of Xe than Kr (due to stronger van der Waals forces) but faster diffusion of Kr (due to smaller kinetic diameter). Therefore the overall membrane selectivity towards Kr will be determined by competition between these two effects. A main objective of this study is to quantify and understand adsorption, diffusion, and permeation in detail and thereby obtain: (1) fundamental parameters useful for design calculations of a Kr/Xe separation membrane process, and (2) an experimental and modeling framework that can provide guidance on the expected limits of performance of SAPO-34 and other zeolite materials. (authors)

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Feasibility of carbon foam-based sorbents for the abatement of gaseous mercury and iodine

The U.S. Department of Energy Hanford Site in Washington State is in the process of commissioning the Waste Treatment and Immobilization Plant to process a portion of the 54 million gallons of radioactive and chemical waste from cold war weapon production. Technologies for the capture of volatile species of concern are still being assessed, and new methods and materials are developed as operational and flowsheet mission risks are identified. One such area still being assessed is the abatement efficacy of the Carbon Adsorber units to retain gaseous mercury and 129 I released during processing. It is challenging to predict the mercury chemistry due to the variability of the feed, and different methods/materials are required for the capture of gaseous Hg 0 and Hg II compounds. In this study, the feasibility of using developmental carbon foam (CF) sorbents for the capture of iodine and mercury was assessed using static and dynamic flow testing and compared against a commercially available sorbent, BATII-37. Both CF and CF functionalized with bismuth particles (CF-Bi) chemisorbed iodine, and CF-Bi had similar mercury capture performance to BATII-37 in dynamic flow tests. While species loading concentrations were measurable, limitations in achieving a mass balance prevented a full evaluation of capture efficacy. Nonetheless, the results serve as an important first step in demonstrating the potential for simultaneous iodine and mercury capture.

Hanford site↗

UMo Solutions Processing in La Hague Cold Crucible Induction Melter: the Feedback From the First Years of Operation - 16376

250 cubic meters of high-level liquid waste from reprocessed U-Mo-Sn-Al spent fuel, used in Gas Cooled Reactors (GCR), were produced during the mid-1960's at La Hague facility. These 'UMo' solutions are less radioactive than the current fission product concentrates coming from ongoing reprocessing activities, but are very rich in molybdenum and phosphorus whose contents make the molten glass quite corrosive and require a high-temperature glass formulation to obtain sufficiently high waste loading factors (12% in molybdenum oxide). Hence the use of the Cold Crucible Induction Melter (CCIM) technology to process such solutions has been deemed a good opportunity for AREVA to meet its performance expectations. In addition to being very corrosive, the UMo waste is quite challenging to process as the molybdenum has a strong tendency to stick in the calciner and causes clogging issues in off-gas treatment equipment. Therefore, the process and technological qualifications were deployed in order to address these specific issues. UMo solutions processing in the La Hague CCIM has started in January 2013 and is currently ongoing. During this period (from 2013 to 2015), many data have been collected to confirm the process parameters that were defined during the qualification of this innovating process. Even if some difficulties occurred, operations teams experience along with engineering and R and D support allowed managing them. This paper presents the start-up methodology and the feedback from the first years of UMo solutions processing with the CCIM technology at La Hague site. Lessons learned are presented with the difficulties encountered and the solutions implemented, emphasizing the benefits of a close integration between R and D, engineering and operations teams. (authors)

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Radioactive Water Treatment at a United States Environmental Protection Agency Superfund Site - 12322

A water treatment system at a United States Environmental Protection Agency (USEPA) Superfund site impacted by radiological contaminants is used to treat water entering the site. The United States Army Corps of Engineers (USACE) is actively managing the remedial action for the USEPA using contracts to support the multiple activities on site. The site is where former gas mantle production facilities operated around the turn of the century. The manufacturing facilities used thorium ores to develop the mantles and disposed of off-specification mantles and ore residuals in the surrounding areas. During Site remedial actions, both groundwater and surface water comes into contact with contaminated soils and must be collected and treated at an on-site treatment facility. The radionuclides thorium and radium with associated progeny are the main concern for treatment. Suspended solids, volatile organic compounds, and select metals are also monitored during water treatment. The water treatment process begins were water is pumped to a collection tank where debris and grit settle out. Stored water is pumped to a coagulant tank containing poly-aluminum chloride to collect dissolved solids. The water passes into a reaction tube where aspirated air is added or reagent added to remove Volatile Organic Compounds (VOC'S) by mass transfer and convert dissolved iron to a solid. The water enters the flocculent polymer tank to drop solids out. The flocculated water overflows to a fluidized bed contact chamber to increase precipitation. Flocculation is where colloids of material drop out of suspension and settle. The settled solids are periodically removed and disposed of as radioactive waste. The water is passed through filters and an ion exchange process to extract the radionuclides. Several million liters of water are processed each year from two water treatment plants servicing different areas of the remediation site. Ion exchange resin and filter material are periodically replaced and disposed of as radioactive waste. A total of 0.85 m{sup 3} of waste sludge per year requires disposal on average, in addition to another 6.6 m{sup 3} of waste cartridge filters. All water discharges are regulated by a state of New Jersey Pollutant Discharge Elimination System Permit implemented by the Federal Water Pollution Control Act (Clean Water Act). Laboratory analyses are required to satisfy requirements of the state NPDES permit. Specific monitoring parameters and discharge rates will be provided. Use of the water treatment systems drastically reduces the amount of contaminated water requiring solidification and water disposal to near zero. Millions of liters of potentially contaminated water from excavation activities is treated and released within permit limits. A small volume of solid radioactive waste (21 cubic meters) is generated annually from water treatment process operations. Management of ground and surface water is effectively controlled in remediation areas by the use of sumps, erosion control measures and pumping of water to storage vessels. Continued excavations can be made as water impacting the site is effectively controlled. (authors)

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Development of Advanced T-OZON{sup TM} for PWR Decommissioning (2) - 18170

The number of aging nuclear power plants (NPPs) slated for closure around the world has increased. The majority of them are PWRs. Minimization of radiation exposure for PWR decommissioning workers is one of the key factors in decommissioning in order to apply the as low as reasonably achievable (ALARA) principle. To this end, it is desirable to establish a chemical decontamination method to reduce the exposure of PWR decommissioning workers. Toshiba developed T-OZON{sup TM}, a chemical decontamination method for BWRs [1, 2, 3]. To date, the method has been applied more than 90 times in Japanese BWR plants. The reduction in radiation exposure of workers achieved by applying T-OZON{sup TM} is estimated at about 300-2700 man mSv [4]. A major feature of T-OZON{sup TM} is the reduced amount of radioactive waste produced when compared to other decontamination processes. Oxide films on PWR wetted surfaces are harder to decontaminate than those in a BWR due to their chemical composition. To apply T-OZON{sup TM} to PWR oxide films, it is necessary to modify the process conditions. (authors)

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STATISTICAL EVALUATION OF SMALL SCALE MIXING DEMONSTRATION SAMPLING AND BATCH TRANSFER PERFORMANCE - 12093

The ability to effectively mix, sample, certify, and deliver consistent batches of High Level Waste (HLW) feed from the Hanford Double Shell Tanks (DST) to the Waste Treatment and Immobilization Plant (WTP) presents a significant mission risk with potential to impact mission length and the quantity of HLW glass produced. DOE's Tank Operations Contractor, Washington River Protection Solutions (WRPS) has previously presented the results of mixing performance in two different sizes of small scale DSTs to support scale up estimates of full scale DST mixing performance. Currently, sufficient sampling of DSTs is one of the largest programmatic risks that could prevent timely delivery of high level waste to the WTP. WRPS has performed small scale mixing and sampling demonstrations to study the ability to sufficiently sample the tanks. The statistical evaluation of the demonstration results which lead to the conclusion that the two scales of small DST are behaving similarly and that full scale performance is predictable will be presented. This work is essential to reduce the risk of requiring a new dedicated feed sampling facility and will guide future optimization work to ensure the waste feed delivery mission will be accomplished successfully. This paper will focus on the analytical data collected from mixing, sampling, and batch transfer testing from the small scale mixing demonstration tanks and how those data are being interpreted to begin to understand the relationship between samples taken prior to transfer and samples from the subsequent batches transferred. An overview of the types of data collected and examples of typical raw data will be provided. The paper will then discuss the processing and manipulation of the data which is necessary to begin evaluating sampling and batch transfer performance. This discussion will also include the evaluation of the analytical measurement capability with regard to the simulant material used in the demonstration tests. The paper will conclude with a discussion of the analysis results illustrating the relationship between the pre-transfer samples and the batch transfers, which support the recommendation regarding the need for a dedicated feed sampling facility.

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Sub-Grid Model Improving Shrinking Core Simulations of Redox-Sensitive Technetium Release From Slag Cement Waste Forms - 17295

Numerical simulation of Tc transport in reducing cementitious materials undergoing oxidation is challenging because the effective solid-solute partition coefficient (K{sub d}) varies greatly between the reduced and oxidized states, assuming the Tc mass loading far exceeds that required to reach solubility in the aqueous phase, as is typical in waste disposal. In a conventional finite-volume formulation, the local aqueous concentration increases orders of magnitude when a computational cell switches from a reducing to oxidizing condition, which is an artifact of numerical discretization. In principal such artifacts can be reduced to an insignificant level by refining the computational grid. However, this approach is not feasible in typical facility scale applications due to computer runtime and storage limitations. In this paper an alternative sub-grid Tc release model is derived to approximately capture redox processes occurring at scales smaller than the computational mesh. This alternative approach introduces minimal additional computational expense, while significantly reducing numerical artifacts in the form of Tc concentration / flux spikes. The method is illustrated for two simple geometries and the Savannah River Site Saltstone waste Disposal Facility. The sub-grid model is shown to significantly reduce artificial spikes in Tc-99 release, resulting in more physically realistic numerical simulations. (authors)

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Separation of Zirconium from Zircaloy-2 for Spent Nuclear Fuel Cladding Applications using a Chloride Volatility Process

The United States produces a large amount of cladding material from used nuclear fuel, expected to approach 1,000 MT/year for the next 50 years. The recovery of zirconium from the cladding material would represent a ∼50% savings on the geologic waste disposal requirement, and savings of >$40 M/year due to the cost of hafnium-free zirconium. Previous simulation studies have shown that in the irradiated cladding, the major activation products found are {sup 125}Sb, {sup 60}Co, and {sup 93m}Nb, and the major fission product found is {sup 137}Cs. These radioisotopes make it impossible to treat the cladding as low level waste. In a chlorination method, zirconium cladding reacts with Cl{sub 2} at 350-380 deg. C to produce mainly ZrCl{sub 4}. The zirconium tetrachloride has a relatively low boiling point (sublimes at 330 deg. C) which allows its separation from other products, and so it can be treated as low level waste for disposal or recycling. This chlorination approach has been proposed for the reprocessing of zirconium. However, previous work has observed element impurities (Fe, Sn, Cr, Cs, Sb, and Nb) in the recovered ZrCl{sub 4} meaning that additional steps are necessary in a chlorination process previous to the reduction of ZrCl{sub 4} to the metallic form. The chlorination process for zirconium reprocessing has been highly encouraged as it has proven more efficient than previous mechanical processes, redox processes, and other chemical methods such as iodination. The overall goal of this project is to develop the road map for a chlorination process that will yield high purity zirconium. The current study focuses on the recovery of ZrCl{sub 4} from non-irradiated alloys used as nuclear fuel cladding. (authors)

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

International Low Level Waste Disposal Practices and Facilities

The safe management of nuclear waste arising from nuclear activities is an issue of great importance for the protection of human health and the environment now and in the future. The primary goal of this report is to identify the current situation and practices being utilized across the globe to manage and store low and intermediate level radioactive waste. The countries included in this report were selected based on their nuclear power capabilities and involvement in the nuclear fuel cycle. This report highlights the nuclear waste management laws and regulations, current disposal practices, and future plans for facilities of the selected international nuclear countries. For each country presented, background information and the history of nuclear facilities are also summarized to frame the country's nuclear activities and set stage for the management practices employed. The production of nuclear energy, including all the steps in the nuclear fuel cycle, results in the generation of radioactive waste. However, radioactive waste may also be generated by other activities such as medical, laboratory, research institution, or industrial use of radioisotopes and sealed radiation sources, defense and weapons programs, and processing (mostly large scale) of mineral ores or other materials containing naturally occurring radionuclides. Radioactive waste also arises from intervention activities, which are necessary after accidents or to remediate areas affected by past practices. The radioactive waste generated arises in a wide range of physical, chemical, and radiological forms. It may be solid, liquid, or gaseous. Levels of activity concentration can vary from extremely high, such as levels associated with spent fuel and residues from fuel reprocessing, to very low, for instance those associated with radioisotope applications. Equally broad is the spectrum of half-lives of the radionuclides contained in the waste. These differences result in an equally wide variety of options for the management of radioactive waste. There is a variety of alternatives for processing waste and for short term or long term storage prior to disposal. Likewise, there are various alternatives currently in use across the globe for the safe disposal of waste, ranging from near surface to geological disposal, depending on the specific classification of the waste. At present, there appears to be a clear and unequivocal understanding that each country is ethically and legally responsible for its own wastes, in accordance with the provisions of the Joint Convention on the Safety of Spent Fuel Management and on the Safety of Radioactive Waste Management. Therefore the default position is that all nuclear wastes will be disposed of in each of the 40 or so countries concerned with nuclear power generation or part of the fuel cycle. To illustrate the global distribution of radioactive waste now and in the near future, Table 1 provides the regional breakdown, based on the UN classification of the world in regions illustrated in Figure 1, of nuclear power reactors in operation and under construction worldwide. In summary, 31 countries operate 433 plants, with a total capacity of more than 365 gigawatts of electrical energy (GW[e]). A further 65 units, totaling nearly 63 GW(e), are under construction across 15 of these nations. In addition, 65 countries are expressing new interest in, considering, or actively planning for nuclear power to help address growing energy demands to fuel economic growth and development, climate change concerns, and volatile fossil fuel prices. Of these 65 new countries, 21 are in Asia and the Pacific region, 21 are from the Africa region, 12 are in Europe (mostly Eastern Europe), and 11 in Central and South America. However, 31 of these 65 are not currently planning to build reactors, and 17 of those 31 have grids of less than 5 GW, which is said to be too small to accommodate most of the reactor designs available. For the remaining 34 countries actively planning reactors, as of September 2010: 14 indicate a strong intention to precede with introduction of nuclear power; 7 are preparing but haven't made a final decision, 10 have made a decision and are preparing infrastructure, 2 have ordered a new nuclear power plant, and 1 has a plant under construction. In all countries interested in pursuing nuclear power, it is necessary for the governments to create an environment for investment and advancement of nuclear power, including development of a professional and independent regulatory framework and regime, knowledge and refinement of skills in nuclear safety and control, definition of policies on nuclear waste management and decommissioning, and participation in international non-proliferation measures. Specifically related to radioactive waste management, nuclear facilities and industries that utilize radioactive material work to well-established safety standards for the management of their waste.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

Project Execution Plan for the Remote Handled Low-Level Waste Disposal Project

As part of ongoing cleanup activities at the Idaho National Laboratory (INL), closure of the Radioactive Waste Management Complex (RWMC) is proceeding under the Comprehensive Environmental Response, Compensation, and Liability Act (42 USC 9601 et seq. 1980). INL-generated radioactive waste has been disposed of at RWMC since 1952. The Subsurface Disposal Area (SDA) at RWMC accepted the bulk of INL’s contact and remote-handled low-level waste (LLW) for disposal. Disposal of contact-handled LLW and remote-handled LLW ion-exchange resins from the Advanced Test Reactor in the open pit of the SDA ceased September 30, 2008. Disposal of remote-handled LLW in concrete disposal vaults at RWMC will continue until the facility is full or until it must be closed in preparation for final remediation of the SDA (approximately at the end of fiscal year FY 2017). The continuing nuclear mission of INL, associated ongoing and planned operations, and Naval spent fuel activities at the Naval Reactors Facility (NRF) require continued capability to appropriately dispose of contact and remote handled LLW. A programmatic analysis of disposal alternatives for contact and remote-handled LLW generated at INL was conducted by the INL contractor in Fiscal Year 2006; subsequent evaluations were completed in Fiscal Year 2007. The result of these analyses was a recommendation to the Department of Energy (DOE) that all contact-handled LLW generated after September 30, 2008, be disposed offsite, and that DOE proceed with a capital project to establish replacement remote-handled LLW disposal capability. An analysis of the alternatives for providing replacement remote-handled LLW disposal capability has been performed to support Critical Decision-1. The highest ranked alternative to provide this required capability has been determined to be the development of a new onsite remote-handled LLW disposal facility to replace the existing remote-handled LLW disposal vaults at the SDA. Several offsite DOE and commercial disposal options exist for contact-handled LLW; however, offsite disposal options are either not currently available (i.e., commercial disposal facilities), practical, or cost-effective for all remote-handled LLW streams generated at INL. Offsite disposal of all INL and tenant-generated remote-handled waste is further complicated by issues associated with transporting highly radioactive waste in commerce; and infrastructure and processing changes at the generating facilities, specifically NRF, that would be required to support offsite disposal. The INL Remote-Handled LLW Disposal Project will develop a new remote handled LLW disposal facility to meet mission-critical, remote-handled LLW disposal needs. A formal DOE decision to proceed with the project has been made in accordance with the requirements of National Environmental Policy Act (42 USC§ 4321 et seq.). Remote-handled LLW is generated from nuclear programs conducted at INL, including spent nuclear fuel handling and operations at NRF and operations at the Advanced Test Reactor. Remote-handled LLW also will be generated by new INL programs and from segregation and treatment (as necessary) of remote handled scrap and waste currently stored in the Radioactive Scrap and Waste Facility at the Materials and Fuels Complex.

99 GENERAL AND MISCELLANEOUS↗

Solid secondary waste testing for maintenance of the Hanford Integrated Disposal Facility Performance Assessment - FY 2017

The Waste Treatment and Immobilization Plant (WTP) at Hanford is being constructed to treat 56 million gallons of radioactive waste currently stored in underground tanks at the Hanford site. Operation of the WTP will generate several solid secondary waste (SSW) streams including used process equipment, contaminated tools and instruments, decontamination wastes, high-efficiency particulate air filters (HEPA), carbon adsorption beds, silver mordenite iodine sorbent beds, and spent ion exchange resins (IXr) all of which are to be disposed in the Integrated Disposal Facility (IDF). An applied research and development program was developed using a phased approach to incrementally develop the information necessary to support the IDF PA with each phase of the testing building on results from the previous set of tests and considering new information from the IDF PA calculations. This report contains the results from the exploratory phase, Phase 1 and preliminary results from Phase 2. Phase 3 is expected to begin in the fourth quarter of FY17.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗