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All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Technology Maturation of Hot Isostatic Pressing for Nuclear Waste Treatment - 20259

ANSTO is constructing a nuclear waste treatment facility for the immobilization of intermediate-level liquid waste (ILLW) from its nuclear medicine production [1]. This facility shall deploy ANSTO Synroc process technology that converts a liquid waste stream into a durable solid wasteform. Hot Isostatic pressing (HIP) shall be employed to consolidate the dry powdered waste effectively reducing the waste volume and immobilizing the waste components. This paper presents the technology maturation for HIP technology for utilisation in a nuclear waste treatment facility. The HIP has been designed to operate in a remote shielded enclosure, fully integrated with the front-end powder production. Attention has been given in the HIP system design to ensure that it can operate and be maintained to achieve the required production output of the facility. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2020

Spent Nuclear Fuel Storage and Radioactive Waste Disposal in the United States: A Law and Policy Analysis - 20302

While Congress plays political football, spent nuclear fuel continues to sit in de facto interim nuclear waste storage sites throughout the country. This ad hoc approach - if it can even be called an approach - to nuclear waste management is in no one's best interests, because of financial, safety, environmental, and national security concerns with the status quo. Senate leadership had asserted that an up-or-down vote on the Yucca Mountain Project would take place in September or October 2019, but that did not occur. Rather, a conference bill was agreed to, and it provided that, although the nuclear program should receive some funding, funding was not made available for centralized interim storage ('CIS') or the Yucca Mountain Project. The President's FY2021 Budget Request does not contain any proposed funding for the Yucca Mountain Project ('the Project'). This paper will discuss the implications of that process, both for the Project itself and for the U.S. nuclear waste program more generally. In order to provide context for the current situation, this paper will begin by chronicling the history of U.S. nuclear waste management, from the passage of the Nuclear Waste Policy Act of 1982 and to the present day. It will discuss the roles of the U.S. Department of Energy, the Nuclear Regulatory Commission, federal and state political delegations, and the nuclear energy industry. The paper will then identify key themes that can be expected to affect the future of nuclear waste management in the United States. For example, it will consider whether development of additional CIS facilities is a viable short- to medium-term solution. CIS facilities may relieve immediate pressure at decommissioned or soon-to-be-decommissioned nuclear power plants; but with that pressure partially alleviated, support for building a long-term repository may be reduced. It will also discuss opposition by the State of New Mexico and others to the proposed New Mexico CIS project, based not only on siting concerns but also whether it might become a de facto repository, and whether the State of Texas and others may also be opposed, for similar reasons, to the proposed CIS facility in Texas. Additionally, the paper will examine consent-based siting and its implications for Nevada and other states that are potential hosts for spent nuclear fuel storage and disposal facilities. Further, if the Project is not a politically viable solution, the paper will examine whether it is now time for serious consideration of an alternate location for a permanent repository, as well as consideration of other options entirely, such as deep geologic disposal. The paper will conclude by looking ahead to the 2020 elections. It will describe the positions of candidates (particularly Presidential candidates) on spent nuclear fuel storage and disposal options, without advocating for any particular candidate or political party. Perhaps in 2020, we will at least see a start to a solution to the seemingly intractable problem of nuclear waste management in the United States. (authors)

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

Estimation of and barriers to waste heat recovery from harsh environments in industrial processes

This paper discusses the industrial potential for waste heat recovery (WHR) in harsh environments – defined as a waste heat stream having either a temperature of at least 650 °C or containing reactive constituents that complicate heat recovery. The analysis covers five industries (steel, aluminum, glass, cement, and lime), chosen based on volume of production, discharge of exhaust gases containing components that present harsh environments, possibility of recovering considerably more heat than currently recovered, and current lack of acceptable WHR options. The total potential energy savings identified in harsh environment waste heat streams from these industries is equal to 15.4% (113.6 TWh) of the process heat energy lost in U.S. manufacturing. Existing technologies and materials for these industries are evaluated and the recoverable waste heat from harsh environment gas for each industrial sector is estimated. Finally, an in-depth summary of each waste heat source shows exactly where waste heat can be recovered and what specific issues must be addressed. The most potential lies within steel blast furnaces (46 TWh/year). Other waste heat streams considered include steel electric arc furnaces (14.1 TWh/year), flat glass (3.6 TWh/year), container glass (5.7 TWh/year), glass fiber (1.1 TWh/year), specialty glass (2.2 TWh/year), aluminum melting furnaces (4.7 TWh/year), cement (17.1 TWh/year), and lime (10.5 TWh/year). Furthermore attempts to recover waste heat in harsh environments have been mostly unsuccessful, advances in research and technology could unlock an enormous potential for energy and cost savings.

42 ENGINEERING↗
DOE OSTI2015

Impacts of policy and market incentives for solid waste recycling in Dhaka, Bangladesh

Highlights: • Bangladesh’s industry and population are growing rapidly, producing more urban waste. • Recycling reduces the solid waste management burden of Municipalities. • A wide array of informal and formal actors is involved in collection and recycling. • Demand for recycled materials and renewable energy creates market incentives. • Policy incentives exist, but they only reach the formal industry. - Abstract: Solid waste mismanagement in Dhaka, Bangladesh, illustrates a well-known market failure which can be summarized as: waste is a resource in the wrong place. Inorganic materials such as plastic or paper can be used to feed the demand for recycled materials in the industrial sector. Organic materials can be converted and used in the nutrient-starved agricultural sector which is currently heavily depending on chemical fertilizers. They are also a feedstock to generate renewable energy in the form of biogas for this energy-starved country relying on diminishing natural gas reserves and increasing import of coal. Reality however does not capitalize on this potential; instead the waste is a burden for municipal authorities who spend large portions of their budgets attempting to transport it out of the city for discharge into landfills. The major part of these materials still remains uncollected in the residential areas and is discarded indiscriminately in open spaces, polluting the residents’ living environment including water, soil and air resources, in the city and beyond. Bangladeshi authorities have, to some extent, recognized this market failure and have developed policies to encourage the development of waste recycling activities. It is also important to note that this market failure is only partial: a large, mostly informal recycling sector has developed in Bangladesh, focusing on inorganic recyclables of market value. The fact that this sector remains largely informal means that these actors perceive significant barriers to formalization. Comparatively, the organic waste recycling sector is less driven by market mechanisms. Competition from chemical fertilizers and fossil fuels is fierce and hinders the development of market opportunities for compost and renewable energy. Nevertheless commercial production of compost and biogas from organic municipal waste is formalized and benefiting from policy incentives.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2015

Life cycle assessment of integrated waste management systems for alternative legacy scenarios of the London Olympic Park

Highlights: • Application of LCA in planning integrated waste management systems. • Environmental valuation of 3 legacy scenarios for the Olympic Park. • Hot-spot analysis highlights the importance of energy and materials recovery. • Most environmental savings are achieved through materials recycling. • Sensitivity analysis shows importance of waste composition and recycling rates. - Abstract: This paper presents the results of the life cycle assessment (LCA) of 10 integrated waste management systems (IWMSs) for 3 potential post-event site design scenarios of the London Olympic Park. The aim of the LCA study is to evaluate direct and indirect emissions resulting from various treatment options of municipal solid waste (MSW) annually generated on site together with avoided emissions resulting from energy, materials and nutrients recovery. IWMSs are modelled using GaBi v6.0 Product Sustainability software and results are presented based on the CML (v.Nov-10) characterisation method. The results show that IWMSs with advanced thermal treatment (ATT) and incineration with energy recovery have the lowest Global Warming Potential (GWP) than IWMSs where landfill is the primary waste treatment process. This is due to higher direct emissions and lower avoided emissions from the landfill process compared to the emissions from the thermal treatment processes. LCA results demonstrate that significant environmental savings are achieved through substitution of virgin materials with recycled ones. The results of the sensitivity analysis carried out for IWMS 1 shows that increasing recycling rate by 5%, 10% and 15% compared to the baseline scenario can reduce GWP by 8%, 17% and 25% respectively. Sensitivity analysis also shows how changes in waste composition affect the overall result of the system. The outcomes of such assessments provide decision-makers with fundamental information regarding the environmental impacts of different waste treatment options necessary for sustainable waste management planning.

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

Modelling informally collected quantities of bulky waste and reusable items in Austria

Highlights: • Informal collectors from Hungary collect bulky waste and reusable items in Austria. • Two methodologies were applied to estimate the informally collected quantities. • Both approaches lead to an estimation of roughly 100,000 t p.a. informally collected. • The formal Austrian system collects 72 kg/cap/yr of bulky waste, WEE & scrap metal. • Informal collection amounts to approx. 12 kg/cap/yr. - Abstract: Disparities in earnings between Western and Eastern European countries are the reason for a well-established informal sector actively involved in collection and transboundary shipment activities from Austria to Hungary. The preferred objects are reusable items and wastes within the categories bulky waste, WEEE and metals, intended to be sold on flea markets. Despite leading to a loss of recyclable resources for Austrian waste management, these informal activities may contribute to the extension of the lifetime of certain goods when they are reused in Hungary; nevertheless they are discussed rather controversially. The aim of this paper is to provide objective data on the quantities informally collected and transhipped. The unique activities of informal collectors required the development and implementation of a new set of methodologies. The concept of triangulation was used to verify results obtained by field visits, interviews and a traffic counting campaign. Both approaches lead to an estimation of approx. 100,000 t per year of reusable items informally collected in Austria. This means that in addition to the approx. 72 kg/cap/yr formally collected bulky waste, bulky waste wood, household scrap (excluding packaging) and WEEE, up to a further 12 kg/cap/yr might, in the case that informal collection is abandoned, end up as waste or in the second-hand sector.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2017

Anaerobic digestion of solid agroindustrial waste in semi-continuous mode: Evaluation of mono-digestion and co-digestion systems

Highlights: • Agroindustrial waste were co-digested with an artificial organic fraction. • Variations in organic loading rate and hydraulic retention time were studied. • Sequential feeding of the substrates based on their seasonality was investigated. • Co-digestion resulted in higher methane yields compared with mono-digestion. • Applying sequential feeding led to a more equilibrated system operation. - Abstract: The present study aimed at investigating the anaerobic digestion of four agroindustrial waste, namely cotton gin waste, winery waste, olive pomace and juice industry waste, in semi-continuous mode, conducting mono-digestion and co-digestion assays, using an artificial organic fraction sample as co-substrate. These assays were divided into two groups, in which different conditions were applied. Group I investigated the variation in two operational parameters, i.e. the organic loading rate (OLR) and the hydraulic retention time (HRT), while in Group II, the assays were fed with different substrates in a sequential order. Results showed more elevated specific methane yields for co-digestion assays compared with mono-digestion assays. Maximum yields were achieved at an OLR of 1.0 gVS/(L·d) and a HRT reduced to half of the initial. Further reduction of the HRT coupled to an increase of the OLR generally caused a significant decrease of specific methane yields, as well as one case of severe overloading, i.e. the mono-digestion of juice industry waste, which resulted in instability and ultimately system failure. Sequential feeding with different substrates led to a more equilibrated operation, especially for co-digestion systems, with higher specific methane yields being observed during the phases corresponding to winery waste and juice industry waste substrates. Overall more positive results were obtained in the cases in which the latter substrates were fed to the reactors at process startup.

09 BIOMASS FUELS↗
DOE OSTI2017

An optimization model for collection, haul, transfer, treatment and disposal of infectious medical waste: Application to a Greek region

Highlights: • We developed an optimization model to minimize cost of infectious waste management. •Two different software were used for model solution. • Model optimizes locations and capacities of treatment plants and transfer stations. • The higher percentage of total cost was due to construction of the treatment plant. • Sensitivity analysis with respect to fuel cost and waste production was conducted. - Abstract: The objective of this work was to develop an optimization model to minimize the cost of a collection, haul, transfer, treatment and disposal system for infectious medical waste (IMW). The model calculates the optimum locations of the treatment facilities and transfer stations, their design capacities (t/d), the number and capacities of all waste collection, transport and transfer vehicles and their optimum transport path and the minimum IMW management system cost. Waste production nodes (hospitals, healthcare centers, peripheral health offices, private clinics and physicians in private practice) and their IMW production rates were specified and used as model inputs. The candidate locations of the treatment facilities, transfer stations and sanitary landfills were designated, using a GIS-based methodology. Specifically, Mapinfo software with exclusion criteria for non-appropriate areas was used for siting candidate locations for the construction of the treatment plant and calculating the distance and travel time of all possible vehicle routes. The objective function was a non-linear equation, which minimized the total collection, transport, treatment and disposal cost. Total cost comprised capital and operation costs for: (1) treatment plant, (2) waste transfer stations, (3) waste transport and transfer vehicles and (4) waste collection bins and hospital boxes. Binary variables were used to decide whether a treatment plant and/or a transfer station should be constructed and whether a collection route between two or more nodes should be followed. Microsoft excel software was used as installation platform of the optimization model. For the execution of the optimization routine, two completely different software were used and the results were compared, thus, resulting in higher reliability and validity of the results. The first software was Evolver, which is based on the use of genetic algorithms. The second one was Crystal Ball, which is based on Monte Carlo simulation. The model was applied to the Region of East Macedonia – Thrace in Greece. The optimum solution resulted in one treatment plant located in the sanitary landfill area of Chrysoupolis, required no transfer stations and had a total management cost of 38,800 €/month or 809 €/t. If a treatment plant is sited in the most eastern part of the Region, i.e., the industrial area of Alexandroupolis, the optimum solution would result in a transfer station of 23 m{sup 3}, located near Kavala General Hospital, and a total cost of 39,800 €/month or 831 €/t. A sensitivity analysis was conducted and two alternative scenarios were optimized. In the first scenario, a 15% rise in fuel cost and in the second scenario a 25% rise in IMW production were considered. At the end, a cost calculation in €/t/km for every type of vehicle used for haul and transfer was conducted. Also, the cost of the whole system was itemized and calculated in €/t/km and €/t. The results showed that the higher percentage of the total cost was due to the construction of the treatment plant.

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

Comparative Techno-economic Analysis and Life Cycle Assessment of Producing High-Value Chemicals and Fuels from Waste Plastic via Conventional Pyrolysis and Thermal Oxo-degradation

The rapid rise in global plastic production in recent decades has resulted in the massive generation of plastic waste. Over 75% of the plastic waste generated in the United States was sent to landfills, with a meager 8.7% recycled. Plastics are valuable feedstocks for platform chemicals and fuels. Chemical upcycling of waste high-density polyethylene (HDPE) is gaining more attention as a potentially feasible and environmentally friendly plastic waste management technology. Conventional pyrolysis (CPY) and thermal oxo-degradation (TOD) are two chemical upcycling technologies actively researched for decomposing waste HDPE into valuable chemicals and fuels. However, there are few studies on the techno-economic analysis (TEA) and life cycle assessment (LCA) of these technologies for converting waste HDPE to valuable products. This study conducts a comparative TEA and LCA study of the thermochemical decomposition of waste HDPE to produce gaseous (ethylene and propylene) and liquid (naphtha, diesel, and wax) products by CPY and TOD. The study elucidates and compares the impact of hydrocracking longer chain hydrocarbons to produce more valuable products on the TEA and LCA. The TEA showed that the fixed capital investment could range from $\$32.5$ million for TOD without hydrocracking to $\$244$ million for CPY with hydrocracking scenarios. Annual revenues range from $\$28.1$ million to $\$71.5$ million in favor of scenarios with hydrocracking. However, the net present value ranges from $\$1.4$ million to $\$265.8$ million in favor of scenarios without hydrocracking. Sensitivity analysis showed that fixed capital cost, facility capacity, and product prices have the biggest impact on the process economics of the facilities, while utilities and waste transportation to refineries have the biggest impact on environmental impacts. Here, the LCA showed that primary products from scenarios without hydrocracking can be more environmentally friendly than virgin products from petroleum processes. However, TOD and CPY with hydrocracking primary products have more emissions than those of virgin products.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2015

Classification methodology for tritiated waste requiring interim storage

Fusion machines like the ITER experimental research facility will use tritium as fuel. Therefore, most of the solid radioactive waste will result not only from activation by 14 MeV neutrons, but also from contamination by tritium. As a consequence, optimizing the treatment process for waste containing tritium (tritiated waste) is a major challenge. This paper summarizes the studies conducted in France within the framework of the French national plan for the management of radioactive materials and waste. The paper recommends a reference program for managing this waste based on its sorting, treatment and packaging by the producer. It also recommends setting up a 50-year temporary storage facility to allow for tritium decay and designing future disposal facilities using tritiated radwaste characteristics as input data. This paper first describes this waste program and then details an optimized classification methodology which takes into account tritium decay over a 50-year storage period. The paper also describes a specific application for purely tritiated waste and discusses the set-up expected to be implemented for ITER decommissioning waste (current assumption). Comparison between this optimized approach and other viable detritiation techniques will be drawn. (authors)

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2016

Nevada National Security Site Waste Acceptance Criteria (NNSS/WAC)

This document establishes the U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Field Office (NNSA/NFO), Nevada National Security Site Waste Acceptance Criteria (NNSSWAC). The NNSSWAC provides the requirements, terms, and conditions under which the Nevada National Security Site (NNSS) will accept the following: DOE low-level radioactive waste (LLW); DOE mixed low-level waste (MLLW); DOE classified waste/matter; U.S. Department of Defense (DOD) classified waste/matter The LLW and MLLW listed above may also be classified waste. Non-radioactive classified waste is accepted for disposal and shall meet the waste acceptance criteria for radioactive waste as specified in this document. Classified matter may be shipped to the NNSS for permanent burial as classified waste in accordance with the provisions in Section 3.1.18 of this document.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2021

Hanford Supplemental Low Activity Waste Simulant Evaporation Testing for Removal of Organics

The Hanford site has approximately 56 million gallons of radioactive waste stored in 177 underground storage tanks. The Hanford Waste Treatment and Immobilization Plant (WTP) is being built to treat and immobilize the tank waste. The baseline method for immobilization of Low Activity Waste (LAW) is vitrification, but additional immobilization capacity is likely needed to supplement the initial melters. An alternative cementitious waste form is being investigated for that future supplemental immobilization method. However, one impediment to a cementitious waste form is the presence of Land Disposal Restricted (LDR) organic chemicals in tank waste. Developing a method to remove the organics would eliminate that impediment to permit possible use of a cementitious waste form. Savannah River National Laboratory (SRNL) performed testing to examine evaporation as a method to remove some prevalent organics from the Supplemental LAW (SLAW) stream. Samples of product streams from the evaporation were analyzed to determine partitioning of the organics. Modeling was also performed to determine if the experimental and modeling results matched. A description of the experimental details, equipment, and results of that testing are included in this report.The work is intended to inform future SLAW flowsheet development activities and gather useful data about the partitioning of constituents through a possible SLAW feed evaporator.

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

Follow-on Report of Analysis of Approaches to Supplemental Treatment of Low–Activity Waste at the Hanford Nuclear Reservation (Volumes I & II)

The Hanford Site, in southeast Washington State, is preparing to disposition approximately 56,000,000 gallons (56 Mgal) of radioactive and chemically hazardous wastes currently stored in underground tanks at the site. Tank wastes will be divided into a high-activity fraction and a low-activity fraction for subsequent treatment and disposition. A waste processing and treatment facility, the Waste Treatment and Immobilization Plant (WTP), will include the high-level waste (HLW) vitrification facility (WTP HLW Vitrification Facility) for immobilizing the high-activity fraction and a low-activity waste (LAW) vitrification facility (WTP LAW Vitrification Facility) for immobilizing the low-activity fraction. Both facilities will use vitrification technology to immobilize the Hanford tank wastes in a glass waste form.

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

Improved Management of the Technical Interfaces Between the Hanford Tank Farm Operator and the Hanford Waste Treatment Plant - 13383

The Department of Energy (DOE) is constructing the Waste Treatment and Immobilization Plant (WTP) at the Hanford site in Washington to treat and immobilize approximately 114 million gallons of high level radioactive waste (after all retrievals are accomplished). In order for the WTP to be designed and operated successfully, close coordination between the WTP engineering, procurement, and construction contractor, Bechtel National, Inc. and the tank farms operating contractor (TOC), Washington River Protection Solutions, LLC, is necessary. To develop optimal solutions for DOE and for the treatment of the waste, it is important to deal with the fact that two different prime contractors, with somewhat differing contracts, are tasked with retrieving and delivering the waste and for treating and immobilizing that waste. The WTP and the TOC have over the years cooperated to manage the technical interface. To manage what is becoming a much more complicated interface as the WTP design progresses and new technical issues have been identified, an organizational change was made by WTP and TOC in November of 2011. This organizational change created a co-located integrated project team (IPT) to deal with mutual and interface issues. The Technical Organization within the One System IPT includes employees from both TOC and WTP. This team has worked on a variety of technical issues of mutual interest and concern. Technical issues currently being addressed include: - The waste acceptance criteria; - Waste feed delivery and the associated data quality objectives (DQO); - Evaluation of the effects of performing a riser cut on a single shell tank on WTP operations; - The disposition of secondary waste from both TOC and WTP; - The close coordination of the TOC double shell tank mixing and sampling program and the Large Scale Integrated Test (LSIT) program for pulse jet mixers at WTP along with the associated responses to the Defense Nuclear Facilities Safety Board (DNFSB) Recommendation 2010-2; - Development of a set of alternatives to the current baseline that involve aspects of direct feed, feed conditioning, and design changes. The One System Technical Organization has served WTP, TOC, and DOE well in managing and resolving issues at the interface. This paper describes the organizational structure used to improve the interface and several examples of technical interface issues that have been successfully addressed by the new organization. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2017

Terminal Sinking Velocity for Waste Packages Falling in a Deep Borehole - 17063

This evaluation of terminal velocity for a waste package sinking in a deep borehole filled with emplacement fluid was done to support concept development for the Deep Borehole Field Test (DBFT). The DBFT objective is to evaluate the safety and feasibility of the deep borehole disposal (DBD) concept for certain radioactive wastes. The DBD concept calls for emplacing waste packages in the lower 2 km of a borehole drilled into crystalline basement rock to a depth of 5 km. Previous studies identified that accidentally dropping one or more waste packages during emplacement could be an important risk, particularly if a waste package is breached. This study evaluated the range of terminal sinking velocity, which can be used to design waste packages and impact limiters to ensure that breach does not occur. Based on an analytical model of a sinking container, a highly turbulent flow is expected to develop in the emplacement fluid. Turbulence is a complex three-dimensional phenomenon and the applicability of analytical models is limited. To backstop the analytical model and to extend predictions to other package dimensions and fluid properties, numerical simulation was performed using the ANSYS Fluent computational fluid dynamics code. Terminal velocity was calculated for downhole temperatures up to 1200 C, and three emplacement fluids (water, NaCl brine, and NaBr brine). Simulation results confirmed that flow around the sinking container is highly turbulent (Reynolds number 5.6 x 10{sup 4} to 7.3 x 10{sup 5}). Turbulence increases with temperature and decreases with density. Calculated terminal velocity ranges from 1.95 (200 C) to 2.13 m/s (1200 C) in water; 1.61 (200 C) to 1.79 m/s (1200 C) in NaCl; and 1.30 (200 C) to 1.46 m/s (1200 C) in NaBr. Terminal velocity is inversely related to fluid density, and the temperature effect on density appears to have a stronger effect on terminal velocity than the temperature effect on viscosity. The foregoing results are for non-perforated casing, but in practice the casing may be perforated to prepare for cementing, and to allow relief of fluid pressure from thermal expansion after emplacement of heat generating waste, and after final borehole closure. To represent the effect from perforations, the analytical solution was modified to include bypass flow through perforations and in the annulus. A workable perforation scheme is identified, consistent with borehole construction and closure requirements, using 2-cm and 5-cm diameter perforations. This scheme is estimated to limit the terminal velocity to 3 m/s, for reference waste packages falling in water at 400 C. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2017

Recruiting and Retaining Talent within the Global Waste Management and Decommissioning Industry - 17192

Every organisation or project can be defined as the people within it. The difference between having the right people with a culture of loyalty and the wrong people with a culture of high staff turnover is huge. Therefore, the way that the global waste management and decommissioning industry approaches recruitment and retention is a critical success factor. My colleagues and I have been fortunate enough to support organisations in the nuclear industry across more than 30 countries in recruiting and retaining talented professionals with rare skills. This experience has given us a unique first hand insight, and answers for questions including the following: - What attracts graduates and experienced professionals to choose a career in the nuclear industry: in waste management, in operations or in new build? - How can we leverage this knowledge to attract more talented individuals to work in the nuclear industry, and in waste management and decommissioning in particular? - How can organisations access the existing global talent pool within waste management and decommissioning? (including case studies of best practice in global recruiting); - What innovative methods are organisations using to successfully find talent? (methods such as strategic secondments, partnerships and knowledge transfer initiatives); - Why do people typically leave an organization or project in the waste management and decommissioning industry? - What examples of best practice and lessons learned exist that can help us understand and increase staff retention in the waste management and decommissioning industry? This paper will answer the questions above and provide recent and relevant examples to substantiate key observations. The objectives of the presentation are: - To give the audience a summary of best practice and lessons learned related to recruitment and retention in the global waste management and decommissioning industry, and also in the wider nuclear industry; - To show the benefits of taking a global view when looking for talent and explaining how to access the global talent pool; - To provide an insight in to what motivates talented people to join the industry and conversely what de-motivates them and causes them to leave; - To provide information about how organisations in the waste management and decommissioning industry can play to their strengths and better compete with other industries that are recruiting for the same talent; - To provide useful and practical actions that will add value to the audience and their organisations. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2016

Overcoming Waste Removal Challenges at Savannah River Site: A Case Study of Tank 15 - 16198

Tank 15 is a High Level Waste Tank at the Savannah River Site containing sludge waste that had been allowed to dry due to several flaws in the primary tank wall. In order to remove the tank waste, the sludge had to first be re-hydrated. Due to the age of Tank 15 and the thirty years of 'dry sludge tank' status, there were numerous technical challenges and risks that had to be addressed to demonstrate operational readiness to add liquid to a tank with known flaws. Liquid management was a key to readiness since Tank 15 did not have the infrastructure to mitigate waste accumulating in the annulus or to transfer waste out of the primary tank as a means to control a large leak. The project team's fundamental expectation was that some amount of liquid would migrate to the annulus through identified flaws as the sludge waste was re-hydrated. Communication was crucial to ensuring this expectation was propagated to management, the customer, and the regulators. Equipment upgrades, provisions for annulus liquid management (monitoring and removal), and readiness for outgoing transfers mitigated waste migration. Liquid addition methodology and facility modifications were developed to safely re-hydrate the sludge while monitoring the integrity of the primary tank. These efforts culminated in successfully adding 697 m{sup 3} (184,000 gal) of liquid to Tank 15, re-hydrating the sludge waste. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2018

Nuclear, Land marker for a Waste Isolation Site: International Architecture Competition - 18240

The design and construction of a nuclear waste marker must include many architectural considerations. Very little research has been conducted by architects to address this issue to date. Historically, the task of designating a nuclear waste site has been a discussion predominantly contained within the scientific and engineering communities. In an effort to engage architects within this dialogue, arch out loud hosted the NUCLEAR competition as an international, architectural investigation into the design of a nuclear waste site marker. The NUCLEAR competition asks participants to design a marker to designate the site of the Waste Isolation Pilot Plant (WIPP) located near Carlsbad, New Mexico. The marker will be meant to be a means of passive institutional controls (PICs) to deter inadvertent human intrusion upon the site and should last 10,000 years. The NUCLEAR competition defined the purpose of the nuclear waste site marker as a means to communicate the danger of inadvertent intrusion from future generations. The competition requires that entries must be both legible in communication and durable in their construction. The competition brief challenged participants to consider how customs and languages will evolve over time and to predict what motivations future generations might have for digging at the site. Other background information was provided about the site such as how waste was stored and how the unique geology of the site seals the waste. The 1993 Sandia National Laboratories report titled Expert Judgment on Markers to Deter Inadvertent Human Intrusion into the Waste Isolation Pilot Plant [1] was referenced along with the 1992 WIPP Land Withdrawal Act [2], interviews with WIPP scientists [3] involved with the WIPP PICs program and the Nuclear Energy Agency Records Knowledge and Memory working group. Competition participants were given digital 3-D Computer-Aided Design models for reference that included the underground storage portion of the site, existing buildings and the 16-square-mile site boundary identified in the 1992 WIPP Land Withdrawal Act [2]. This paper will: - Provide a detailed description of the submitted proposals including graphic analysis of the visualizations, diagrams, technical drawings, jury comments and statements. - Catalogue and identify the consistent themes within all submissions with possible categories including: 1) overall architectural form and language, 2) integration of written language and symbols within architecture, 3) use of technology and robotics, 4) construction methods and materials. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗