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DOE OSTI2017

Integrated Disposal Facility Performance Assessment: Modeling Consistency to Support Regulatory Decision Making at Hanford - 17398

Under DOE Order 435.1, 'Radioactive Waste Management', Washington River Protection Solutions, LLC and INTERA, Inc are currently preparing a performance assessment for the Hanford Integrated Disposal Facility, a near-surface low-activity waste disposal facility located on the Hanford Site in southeast Washington State. The disposal facility is expected to receive vitrified low-activity waste produced at the Hanford Waste Treatment and Immobilization Plant, as well as other secondary solid wastes generated during the treatment process. The performance assessment performs the analyses that will be relied upon to receive the Disposal Authorization Statement, establish waste acceptance criteria, modify the RCRA permit for the facility and make a waste-incidental-to-reprocessing determination for the vitrified tank waste. In January 2006 in the case State of Washington v. Bodman (Civil No. 2:03-cv-05018-AAM), DOE, the Washington State Department of Ecology (Ecology) and the State of Washington Attorney General's office reached a settlement agreement in Ecology's claim regarding off-site waste shipments to Hanford and the adequacy of modeling in the environmental impact statement. In response to the agreement, the DOE Office of Environmental Management set a policy to establish a consistent use of commercially available and public domain software for a vadose zone and groundwater model platform to support regulatory decisions at Hanford. In October 2012, the Associate Principal Deputy Assistant Secretary for Environmental Management released a memorandum to the manager of the Richland Operation Office directing how future environmental modeling activities to support regulatory decision making on the Hanford Site would be undertaken to be consistent with the 2006 settlement agreement. The preparation of the performance assessment must meet DOE Order 435.1 requirements and the additional direction provided by DOE. This paper will identify the approach taken to comply with the requirements in the 2012 memorandum. The paper will describe how environmental modeling performed for the 2017 Integrated Disposal Facility Performance Assessment was planned in a phased approach and how the current modeling is tied to the analyses that supported the decisions made in the environmental impact statement published in 2012. Additionally, the selection and qualification of the software selected to perform modeling activities for the performance assessment will be described. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2015

Understanding the consequences of hypothetical post-closure transient criticality in a geological disposal facility - 14439

Radioactive Waste Management (RWM) is responsible for implementing geological disposal of the UK's higher-activity radioactive wastes. These wastes include significant quantities of fissile nuclides and, therefore, demonstration of criticality safety for the wastes under disposal conditions forms an important component of RWM's disposal system safety case. At the time of disposal all waste packages will be safely sub-critical. Containment provided by the engineered barrier system of a geological disposal facility (GDF) will ensure that criticality is not possible for some time after disposal. However, as waste packages degrade, fissile and other materials may be mobilised, which could affect the potential for criticality. Although the likelihood of a critical configuration developing is demonstrably low, it cannot be assumed to be zero over long post-closure timescales. The UK environment agencies' Guidance on Requirements for Authorisation for a GDF includes a specific requirement to consider the consequences of hypothetical 'what-if' post-closure criticality. RWM has undertaken a programme of research to model and understand the consequences of hypothetical post-closure criticality events. Initially focused on the scenario of fissile material relocation and accumulation following intermediate level waste (ILW) disposal, two bespoke computer models were developed. The quasi-steady-state (QSS) model considered critical systems maintained by accumulation of fissile materials where the temperature feedback remains negative throughout the transient. The rapid transient model (RTM) considered systems with positive temperature feedback. The QSS model development included a successful comparison with the Oklo natural reactors. With a requirement to consider post-closure criticality for a wider range of potential waste types under different illustrative disposal concepts, the initial transient criticality models had some limitations. For the QSS model this was the assumption of fixed geometry, while the complex functional inputs required in the RTM were not readily available for different materials. For the QSS model this paper describes the model development to allow changing volume; this has enabled its application to 'what-if' scenarios of flooding within a spent fuel waste package and the slumping of a stack of ILW packages. For rapid transient criticality this paper explains how the development of a simpler 'bounding approach' model to complement the RTM has enabled transient criticality analysis for a wider range of host materials. The role of this research in demonstrating post-closure criticality safety of a GDF in the UK is presented in a companion paper which also draws on the results of a parallel research project to demonstrate that the likelihood of post-closure criticality is low. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2010

HTGR Technology Family Assessment for a Range of Fuel Cycle Missions

This report examines how the HTGR technology family can provide options for the once through, modified open cycle (MOC), or full recycle fuel cycle strategies. The HTGR can serve all the fuel cycle missions that an LWR can; both are thermal reactors. Additional analyses are warranted to determine if HTGR “full recycle” service could provide improved consumption of transuranic (TRU) material than LWRs (as expected), to analyze the unique proliferation resistance issues associated with the “pebble bed” approach, and to further test and analyze methods to separate TRISO-coated fuel particles from graphite and/or to separate used HTGR fuel meat from its TRISO coating. The feasibility of these two separation issues is not in doubt, but further R&D could clarify and reduce the cost and enable options not adequately explored at present. The analyses here and the now-demonstrated higher fuel burnup tests (after the illustrative designs studied here) should enable future MOC and full recycle HTGR concepts to more rapidly consume TRU, thereby offering waste management advantages. Interest in “limited separation” or “minimum fuel treatment” separation approaches motivates study of impurity-tolerant fuel fabrication.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2019

Development of an Experimental Approach for Thermal Testing in Bedded Salt - 19431

Safe and permanent isolation of used nuclear fuel (UNF) and high-level nuclear waste (HLW) is an integral component of the cradle-to-grave philosophy of radioactive waste management. Out of the multitude of rock types considered for the permanent deep disposal of nuclear waste (tuff, shale, granite, clay, and salt), salt has received significant interest particularly because of the advantage offered by salt as an impermeable and dry medium with self-sealing properties. The concept of HLW disposal in salt has been investigated through several testing campaigns in the U.S. and in Germany. Serval knowledge gaps still exist in our understanding of how brine is generated and how it transports under heat generating conditions. These knowledge gaps limit our ability to build a robust safety case for the disposal of heat generating waste in salt. The current manuscript reports on efforts performed to develop a field-testing campaign to study brine and water vapor migration in heated salt. The paper summarizes initial work done in a phased thermal testing program in bedded salt at the Waste Isolation Pilot Plant (WIPP), Carlsbad, New Mexico. The testing to date has been focused on existing boreholes and is being used to 'shakedown' the process for implementation of a more refined testing program that will be implemented in freshly drilled boreholes planned for FY2019. We designed and deployed a heater assembly that consisted of a packer, borehole deformation gauge, heater block, a network of thermocouples, and a pressure transducer setup to measure in situ temperature and pressure. The assembly was deployed in an existing borehole and several heating and cooling experiments were performed to test the performance of the different instruments fielded. We report on the results obtained for brine generation as a function of time and heating and cooling cycles and temperature evolution in the rock salt. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2023

Improved scientific knowledge of methanogenesis and methanotrophy needed to slow climate change during the next 30 years

Owing to the high radiative forcing and short atmospheric residence time of methane, abatement of methane emissions offers a crucial opportunity for effective, rapid slowing of climate change. Here, we report on a colloquium jointly sponsored by the American Society for Microbiology and the American Geophysical Union, where 35 national and international experts from academia, the private sector, and government met to review understanding of the microbial processes of methanogenesis and methanotrophy. The colloquium addressed how advanced knowledge of the microbiology of methane production and consumption could inform waste management, including landfills and composts, and three areas of agricultural management: enteric emissions from ruminant livestock, manure management, and rice cultivation. Support for both basic and applied research in microbiology and its applications is urgently needed to accelerate the realization of the large potential for these near-term solutions to counteract climate change.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2012

Blue Ribbon Commission on America's Nuclear Future: Report to the Secretary of Energy

Preamble The Blue Ribbon Commission on America’s Nuclear Future (BRC) was formed by the Secretary of Energy at the request of the President to conduct a comprehensive review of policies for managing the back end of the nuclear fuel cycle and recommend a new strategy. It was co-chaired by Rep. Lee H. Hamilton and Gen. Brent Scowcroft. Other Commissioners are Mr. Mark H. Ayers, the Hon. Vicky A. Bailey, Dr. Albert Carnesale, Sen. Pete Domenici, Ms. Susan Eisenhower, Sen. Chuck Hagel, Mr. Jonathan Lash, Dr. Allison M. Macfarlane, Dr. Richard A. Meserve, Dr. Ernest J. Moniz, Dr. Per Peterson, Mr. John Rowe, and Rep. Phil Sharp. The Commission and its subcommittees met more than two dozen times between March 2010 and January 2012 to hear testimony from experts and stakeholders, to visit nuclear waste management facilities in the United States and abroad, and to discuss the issues identified in its Charter. Additionally, in September and October 2011, the Commission held five public meetings, in different regions of the country, to hear feedback on its draft report. A wide variety of organizations, interest groups, and individuals provided input to the Commission at these meetings and through the submission of written materials. Copies of all of these submissions, along with records and transcripts of past meetings, are available at the BRC website (www.brc.gov). This report highlights the Commission’s findings and conclusions and presents recommendations for consideration by the Administration and Congress, as well as interested state, tribal and local governments, other stakeholders, and the public.

Nuclear waste management, Blue Ribbon Commission, ↗
DOE OSTI2020

Radiological analysis and transmutation calculation of representative castable nanostructured alloys

In this work, radiological analysis regarding the waste management was performed on two current reduced-activation ferritic-martensitic (RAFM) steels Eurofer 97 and F82H and two castable nanostructured alloys (CNAs) CNA1 and CNA3 using the European DEMO first wall spectrum. CNA1 and CNA3 are a new generation of RAFM steels, which have increased amounts of nanoscale carbonitrides and carbides precipitates, respectively, via small composition modifications. Furthermore, the increased nitrogen in CNA1 leads to higher activity at ≥50 years, and thus to the disposal concern under the current NRC regulation. However, the calculation using Fetter’s evaluation leads to reduced waste disposal rating (WDR) of down to 0.25 depending on the damage dose from ~0.05 wt percent nitrogen in CNA1, and thus less concern on the waste disposal. Contact dose rate after 10 years from the first wall replacement primarily depends on the initial Co and Nb impurity levels. Other added elements, such as V and Si in CNA1 and Ti and Mn in CNA3, do not have significant effect on the specific activity, contact dose rate, or decay heat. Composition limits of CNAs are given based on the shallow burial disposal and materials recycling. In addition, composition evolution of typical precipitates in the CNAs was calculated using the DEMO first wall and the HFIR spectra. Larger transmutation-induced composition evolution occurs in the V/Ta-rich carbonitrides in CNA1 than that in the Ti-rich carbides in CNA3.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2017

Sewage sludge disposal strategies for sustainable development

The main objective of the present review is to compare the existing sewage sludge management solutions in terms of their environmental sustainability. The most commonly used strategies, that include treatment and disposal has been favored within the present state-of-art, considering existing legislation (at European and national level), characterization, ecotoxicology, waste management and actual routs used currently in particular European countries. Selected decision making tools, namely End-of-waste criteria and Life Cycle Assessment has been proposed in order to appropriately assess the possible environmental, economic and technical evaluation of different systems. Therefore, some basic criteria for the best suitable option selection has been described, in the circular economy “from waste to resources” sense. The importance of sewage sludge as a valuable source of matter and energy has been appreciated, as well as a potential risk related to the application of those strategies. - Highlights: • Environmental sustainability in sewage sludge management. • Investigation of eco-innovations in wastewater treatment. • Assessment of ecological consequences of sewage sludge disposal.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2015

Advanced Fuels Campaign FY 2015 Accomplishments Report

The mission of the Advanced Fuels Campaign (AFC) is to perform research, development, and demonstration (RD&D) activities for advanced fuel forms (including cladding) to enhance the performance and safety of the nation’s current and future reactors; enhance proliferation resistance of nuclear fuel; effectively utilize nuclear energy resources; and address the longer-term waste management challenges. This report is a compilation of technical accomplishment summaries for FY-15. Emphasis is on advanced accident-tolerant LWR fuel systems, advanced transmutation fuels technologies, and capability development.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2015

Environmental assessment of farm-scaled anaerobic co-digestion for bioenergy production

Highlights: • Anaerobic monodigestion and codigestion were compared. • The environmental advantages of suitable waste management were proved. • The use of cereal crops as feedstock improves biogas yield. • Cultivation step implies the most important environmental hotspot. • Digestate management options were evaluated. - Abstract: The aim of this study was to assess the environmental profile of a bioenergy system based on a co-digestion plant using maize silage and pig slurry as substrates. All the processes involved in the production of bioenergy as well as the avoided processes accrued from the biogas production system were evaluated. The results evidenced the environmental importance of the cultivation step and the environmental credits associated to the avoided processes. In addition, this plant was compared with two different plants that digest both substrates separately. The results revealed the environmental benefits of the utilisation of pig slurry due to the absence of environmental burdens associated with its production as well as credits provided when avoiding its conventional management. The results also presented the environmental drawbacks of the utilisation of maize silage due to the environmental burdens related with its production. Accordingly, the anaerobic mono-digestion of maize silage achieved the worst results. The co-digestion of both substrates was ranked in an intermediate position. Additionally, three possible digestate management options were assessed. The results showed the beneficial effect of digestate application as an organic fertiliser, principally on account of environmental credits due to avoided mineral fertilisation. However, digestate application involves important acidifying and eutrophicating emissions.

09 BIOMASS FUELS↗
DOE OSTI2016

Solidification technology for organic liquid waste combined with solid materials from Cernavoda NPP, Romania - 16453

Canadian Deuterium Uranium (CANDU{sup R}) reactor designs were initially developed in the late 1950's and 1960's by the Atomic Energy of Canada Limited (AECL) in partnership with Ontario Power Generation. CANDU{sup R} 6 reactors are Pressurized Heavy Water Reactors (PHWRs), with an integrated containment system and are designed as either multi or single unit systems. Two single CANDU 6 systems are currently operating at Cernavoda with an additional two units expected to be brought online in the near future. The radioactive waste produced by the plant is currently stored in a waste interim storage facility located on-site. The main sources of radioactive waste in a CANDU plant are: - Primary Heat Transport (PHT) systems, - Moderator systems, - Other sources of radionuclides. The radioactive waste management system at Cernavoda Nuclear Power Plant (NPP) was designed to maintain acceptable levels of safety for workers and to protect human health and the environment from exposure to unacceptable levels of radiation. During the operation of the Cernavoda NPP, a series of waste streams have been generated for waste treatment purposes. One important waste stream is the combination of solid materials and liquid organic waste, creating flammable solids. Flammable solids represent solid materials, such as cloth, plastic, contaminated with oil containing gamma nuclides and H-3 from maintenance activities. This paper explores a method to solve the problem of liquid residues on solid materials by the application of absorbent materials. The existence of liquid residues on solid materials is a common problem at nuclear power stations globally. The primary issue centers on an effective method of eliminating the liquid to allow for the final acceptance and disposal of the solid waste by regulators. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2019

Legacy Waste Removal from Standpipes and Bunkers at Whiteshell Laboratories, Canada - 19040

In 1963 Atomic Energy of Canada Limited (AECL) founded the Whiteshell Nuclear Research Establishment (now Whiteshell Laboratories, WL) in Pinawa, Manitoba to conduct nuclear research. In 1997 AECL made a business decision to discontinue research programs and operations at WL. One of the major decommissioning tasks at WL is to remove radioactive waste from 171 in-ground standpipes and 7 Intermediate Level Waste bunkers located in the Waste Management Area (WMA). Veolia Nuclear Solutions, through its subsidiary Kurion (Canada) Inc., has been selected to design, fabricate, and commission a remote waste access and conditioning system to remediate the waste from the standpipes and ILW bunkers at WL. The agreement builds on Veolia Nuclear Solutions' successfully deploying similar technologies at other projects. This paper describes the bunkers and standpipes structures, the types of wastes stored, the potential hazards (flammable gas and pyrophoric materials), and the equipment proposed by Kurion for safely extracting, sorting, segregating and packaging this waste. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2013

Management of Disused Sealed Sources in Hungary - 13077

Since 1976 the spent and disused radioactive sources arisen in Hungary are stored in a central storage facility called Radioactive Waste Treatment and Disposal Facility operated by Public Limited Company for Radioactive Waste Management. The Facility is responsible for the record keeping, the waste acceptance procedure, the shipment and the storage or disposal (whether a certain source meets the waste acceptance criteria for disposal or not) of sources. Based on the more than 35 year old operation of the facility many experiences have been gathered regarding the technology for long-term storage of sources, the attitude of the users of sources, the evolution of the legislation and the national record keeping system. Recently a new legislation for the security of radioactive materials (including sources) was introduced, first in Central-Europe. It requires special security arrangements from the facility for transport and for storage. Due to the ongoing retrieval of radioactive waste formerly disposed of, partly containing sealed sources, there is a new challenge in the physical inventory control of historical waste. The paper would show the effect of the changes in the legislation system of record keeping or security on the users' attitude for discard of sources and on the management of the sources in the facility. The facility has a unique storage technology (shallow boreholes) in the narrow region. The sealed sources are placed into vertical pipes sunk into the surface. In the beginning, each of the sources were dropped into the pipe directly, recently they are placed in a metal tube first ensuring the retrieval. The lessons learned will be presented. There were several issues to introduce the new security arrangements (partly financially supported by US DOE) for storage and for transportation of sealed sources. These issues are addressed. In the past part of the sealed sources were disposed together with solid radioactive waste packaged in plastic bags. A waste retrieval campaign was fulfilled in 2008 to retrieve the sealed sources. The paper demonstrates the conditions of sealed sources after twenty-year disposal period. As a summary, the paper will share the main experiences of a 35-year old facility, managing radioactive sealed sources in Central Europe. (authors)

07 ISOTOPE AND RADIATION SOURCES↗
DOE OSTI2011

SOLVENT EXTRACTION RESEARCH AND DEVELOPMENT IN THE U.S. FUEL CYCLE PROGRAM

Treatment or processing of used nuclear fuel to recycle uranium and plutonium has historically been accomplished using the well known PUREX process. The PUREX process has been used on an industrial scale for over 60 years in the nuclear industry. Research is underway to develop advanced separation methods for the recovery of other used fuel components, such as the minor actinides (Np, Am, Cm) for possible transmutation in fast spectrum reactors, or other constituents (e.g. Cs, Sr, transition metals, lanthanides) to help facilitate effective waste management options. This paper will provide an overview of new solvent extraction processes developed for advanced nuclear fuel cycles, and summarize recent experimental results. This will include the utilization of new extractants for selective separation of target metals and new processes developed to selectively recover one or more elements from used fuel.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2012

Sensitivity analysis and optimization of the nuclear fuel cycle

A sensitivity study has been conducted to assess the robustness of the conclusions presented in the MIT Fuel Cycle Study. The Once Through Cycle (OTC) is considered as the base-line case, while advanced technologies with fuel recycling characterize the alternative fuel cycles. The options include limited recycling in LWRs and full recycling in fast reactors and in high conversion LWRs. Fast reactor technologies studied include both oxide and metal fueled reactors. The analysis allowed optimization of the fast reactor conversion ratio with respect to desired fuel cycle performance characteristics. The following parameters were found to significantly affect the performance of recycling technologies and their penetration over time: Capacity Factors of the fuel cycle facilities, Spent Fuel Cooling Time, Thermal Reprocessing Introduction Date, and in core and Out-of-core TRU Inventory Requirements for recycling technology. An optimization scheme of the nuclear fuel cycle is proposed. Optimization criteria and metrics of interest for different stakeholders in the fuel cycle (economics, waste management, environmental impact, etc.) are utilized for two different optimization techniques (linear and stochastic). Preliminary results covering single and multi-variable and single and multi-objective optimization demonstrate the viability of the optimization scheme. (authors)

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2018

4th Quarter and Annual Transportation Report FY2018

This report satisfies the U.S. Department of Energy, National Nuclear Security Administration Nevada Field Office (NNSA/NFO) commitment to prepare a quarterly summary of waste shipments to the Nevada National Security Site (NNSS) Radioactive Waste Management Complex (RWMC) in Area 5. This report summarizes the fourth quarter of fiscal year (FY) 2018 and serves as an annual report for the following types of shipments: Low-Level Radioactive Waste (LLW); Mixed Low-Level Radioactive Waste (MLLW); Classified Non-Radioactive (CNR) Waste; Classified Non-Radioactive Hazardous (CNRH) Waste; Tabular summaries are provided that include the following: Number and external volume of LLW, MLLW, and CNR/CNRH shipments; Waste generators for LLW, MLLW, and CNR/CNRH shipments to and on the NNSS; Carriers for LLW, MLLW, and CNR/CNRH shipments to and on the NNSS; Waste generator shipments by quarter; Highway routes used by carriers; Incident and accident data applicable to LLW, MLLW, and CNR/CNRH shipments. In this report, shipments are accounted for upon arrival at the NNSS, while disposal volumes are accounted for upon waste burial. Volume reports showing cubic feet (ft 3 ) generated using the Low-Level Waste Information System may vary slightly due to rounding conventions for conversions from cubic meters to cubic feet. Shipments are transported by motor carriers that are either identified on the U.S. Department of Energy (DOE) Motor Carrier Evaluation Program (MCEP) list, have been evaluated in a manner similar to the MCEP process, or are government vehicles. Government vehicles are not evaluated using the MCEP process but are fully compliant with all transportation regulations and requirements.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2011

Environmental impact of APC residues from municipal solid waste incineration: Reuse assessment based on soil and surface water protection criteria

Highlights: > The Dutch Building Material Decree (BMD) was used to APC residues from MSWI. > BMD is a straightforward tool to calculate expectable loads to the environment of common pollutants. > Chloride load to the environment lead to classification of building material not allowed. > At least a pre-treatment (e.g. washing) is required in order to remove soluble salts. > The stabilization with phosphates or silicates eliminate the problem of heavy metals. - Abstract: Waste management and environmental protection are mandatory requirements of modern society. In our study, air pollution control (APC) residues from municipal solid waste incinerators (MSWI) were considered as a mixture of fly ash and fine particulate solids collected in scrubbers and fabric filters. These are hazardous wastes and require treatment before landfill. Although there are a number of treatment options, it is highly recommended to find practical applications rather than just dump them in landfill sites. In general, for using a construction material, beyond technical specifications also soil and surface water criteria may be used to ensure environmental protection. The Dutch Building Materials Decree (BMD) is a valuable tool in this respect and it was used to investigate which properties do not meet the threshold criteria so that APC residues can be further used as secondary building material. To this end, some scenarios were evaluated by considering release of inorganic species from unmoulded and moulded applications. The main conclusion is that the high amount of soluble salts makes the APC residues a building material prohibited in any of the conditions tested. In case of moulding materials, the limits of heavy metals are complied, and their use in Category 1 would be allowed. However, also in this case, the soluble salts lead to the classification of 'building material not allowed'. The treatments with phosphates or silicates are able to solve the problem of heavy metals, but difficulties with the soluble salts are still observed. This analysis suggests that for APC residues to comply with soil and surface water protection criteria to be further used as building material at least a pre-treating for removing soluble salts is absolutely required.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2024

Concept of Operations for Advanced Reactor Spent Nuclear Fuel Management

This presentation presents a preliminary description of a concept of operations to incorporate advanced-reactor spent nuclear fuel (SNF) into an integrated waste-management system (IWMS). The evaluation includes SNF from four advanced-reactor concepts with the following fuel types: (1) small modular reactors using oxide fuels, (2) tristructural-isotropic (TRISO) fuels, (3) metallic fuels, and (4) fuel salts. To provide context for the proposed concept of operations for advanced reactors, a comparison is made with traditional light-water reactors (LWRs) to identify potential gaps in the IWMS. The technical differences between advanced reactors and LWRs are assessed to determine the feasibility of managing advanced-reactor waste streams using existing operations and technology. This presentation emphasizes fuel types from Advanced Reactor Demonstration Program reactors: Xe 100, which uses TRISO fuel and Natrium, with its metallic fuels while also analyzing management options for molten-salt reactors and advanced light-water reactors (ALWRs). Understanding the storage, transportation, and disposal requirements of SNF is dependent on both the quantity and characteristics of the SNF generated by nuclear reactors. This presentation provides a high level overview, comparing the anticipated concept of operations for different SNFs from advanced reactors. The IWMS includes at-reactor storage, transportation, potential off-site storage, potential treatment, and disposition. To assess the potential effect of advanced-reactor concept of operations on the IWMS, estimates were made for fuel characteristics that contribute to storage, transportation, disposal, and possible treatment of advanced-reactor SNF. These include canister heat load, dose rates, and criticality-control limits, which are important for determining the condition and configuration of the advanced reactor SNF. At-reactor storage of LWR SNF traditionally involves a spent-fuel pool (SFP) before transfer to an independent spent-fuel storage installation. However, some advanced-reactor concepts, particularly those using TRISO and salt fuels, do not anticipate the use of an SFP. This difference in at-reactor storage could impact the IWMS. Additionally, transportation of advanced-reactor SNF may include additional processes tied to potential off gassing, and transportation of microreactor SNF may occur within the reactor vessel. Some advanced-reactor SNF could also undergo treatment to meet requirements of an acceptable waste form for disposition, and the treatment location will be a major contributor to efficiently performing IWMS responsibilities. Moreover, the quantity of SNF generated is an important consideration for IWMS because it could affect the size of the transportation fleet and potential off-site storage requirements. Additionally, volume and heat load are the primary drivers for SNF disposition. This presentation compares potential packaging options for advanced reactor SNF with traditional LWR packaging to provide a high-level comparison for the needs of the IWMS for advanced-reactor SNF.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗