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DOE OSTI2020

FY2019 Performance Assessment Annual Review for the E-Area Low-Level Waste Facility

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2014

Waste Acceptance and Disposal at the Nevada National Security Site

The U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Field Office (NNSA/NFO) relies on the Performance Assessment (PA) and the PA model of the Area 5 Radioactive Waste Management Site (RWMS) at the Nevada National Security Site (NNSS) to make disposal decisions on waste stream profiles submitted by waste generators. Disposal decisions are made following a formal process called the PA review process. This paper presents the PA review process, which is a part of the NNSA/NFO’s Waste Generator Documentation Approval Process. The review process includes three major steps and employs quantitative tools such as the PA-derived factors and probabilistic inventory and PA models developed in GoldSim. The PA-derived radionuclide action levels for waste characterization and reporting are included in the NNSS Waste Acceptance Criteria. Each year, NNSA/NFO reviews approximately 100 to 150 new or revised waste stream profiles. The PA review group ensures that, with the disposal of approved waste streams, the Area 5 RWMS will remain in compliance with the performance objectives of DOE O 435.1, “Radioactive Waste Management.” Examples of the PA review process are given that demonstrate how waste streams with special characteristics are evaluated and disposal decisions are made. The most rigorous profile evaluation is done with the PA model, run with the proposed profile inventory added and results compared to the PA results. Additional analysis and process-modeling are performed for those waste streams with unique features not addressed with the PA model. The results of these analyses and modeling are documented in special analysis reports, reviewed and approved by NNSA/NFO. The examples include (1) profiles with radionuclides not in the PA, (2) profiles including radionuclides with high radon-generation potential, and (3) profiles with high-heat generating radionuclides.

Yucel, Vefa↗

DOE OSTI2015

A cradle to grave decontamination process - 15266

As the rate of decommissioning of nuclear facilities is accelerating there is an ever increasing need for technologies which will decrease dose to operators, reduce overall cost and allow minimization of waste volumes. A new fully integrated decontamination and waste management process is described herein. This method approaches surface decontamination in an integrated fashion in that it deals with the full cycle of the process including the final disposition of the secondary wastes generated during the cleaning cycle. This approach also simplifies decontamination in that it addresses issues observed in previous chemical decontamination applications such as generation of orphan wastes and the requirements for multi-step reagent additions over repeated cycles. The waste management aspect of this system is key to providing a fully integrated process and deals with the issues related to grout formulations in the presence of high waste loadings. (authors)

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DOE OSTI2012

Nuclear Crisis Communications: The Plan Worked. A Critique of NRC Communications in the Fukushima Daiichi Reactor Crisis - 12073

'Call the AV-Photo folks and get someone in here to shoot b-roll. We'll never be able to accommodate the network cameras and the only way I can get this to the media is to produce it ourselves'. Eliot Brenner, Director NRC Office of Public Affairs, March 12, 2011. For the past four years we have been speaking to audiences at Waste Management about communications issues. Last year, though we were kept from attending because of the federal budget crisis, our surrogates described to you the lessons the nuclear industry should draw from the BP Gulf oil spill crisis. Those remarks were delivered 11 days before the Fukushima Daiichi tragedy became the nuclear landmark of a generation - an industry changing event with worldwide ramifications, both in science and regulation and in communications. Eliot Brenner cut his teeth on crisis communication in the aviation industry where tragedy unfolds rapidly. He has been a speech-writer to three cabinet secretaries, spokesman for the Federal Aviation Administration and now spokesman for the Nuclear Regulatory Commission since 2004. Holly Harrington manages the NRC crisis response program and has 26 years federal public affairs experience, including eight years at the Federal Emergency Management Agency. Her crisis experience includes the 1989 Loma Prieta earthquake, numerous hurricanes and floods, Sept 11, and, now Fukushima Daiichi. Rebecca Schmidt is a veteran government relations professional whose decades in Washington include service with the House Armed Services Committee, the House Budget Committee and the Secretary of Defense. Collectively, the Offices of Public Affairs and Congressional Affairs conducted the largest outreach for the agency since Three Mile Island. We worked with the basic rule, described to Waste Management last year just 11 days before Fukushima - communicate early, often and clearly. The response - while not without its problems and lessons - went as smoothly as a chaotic event like Fukushima could go. That was due in large measure to the fact that the NRC has a well-tested system of responding to nuclear emergencies, and we followed our plan. (authors)

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DOE OSTI2017

Decontamination and Decommissioning Program of a Radiopharmaceuticals Production Facility - 17103

On May 2012, Best Medical Belgium (BMB) S.A., a manufacturer of pharmaceutical products located on the nuclear site of Fleurus, was declared bankrupt. According to the Belgian law, ONDRAF/NIRAS (Belgian Radioactive Waste Management Agency) was entrusted with the clean-up and the decommissioning operations of the former BMB facilities, nowadays known as 'ONDRAF/NIRAS Site Fleurus' (ONSF). In June 2015, ONSF launched a Decontamination and Decommissioning (D and D) program, for which Tractebel supports the definition of the clean-up and decommissioning strategies; the drafting of the Final Decommissioning Plan (FDP) and License Application for decommissioning; and the follow-up of the clean-up and upcoming D and D works on site. Four nuclear buildings are part of the clean-up and D and D activities. One of them, Building 14 (B14), represents the most challenging task with the clean-up of highly contaminated areas and their further decommissioning up to greenfield. Beside its two cyclotrons successively used for the production of radioisotopes, this building features hot cells and glove boxes used for the purification of radioisotopes and the conditioning of the final pharmaceutical product. The present paper aims at presenting the development of the D and D program in terms of modifications of existing facilities to allow carrying out the clean-up and D and D activities and the management of dismantled radioactive materials in a safe, efficient and cost-effective way as well as in terms of strategic options to be developed for the FDP. To support the clean-up and D and D activities, several workshops have been designed in order to treat radioactive materials removed from the building rooms. Those workshops feature an input buffer storage area, a common output buffer storage area and installations for the treatment of radioactive materials and waste (handling devices, cutting means, decontamination means, free release measurements means, etc.). Some modifications to the existing auxiliary systems will be required in order to dispose of appropriate systems to operate those workshops in a safe way. Activated concrete structures will constitute the most important part of radioactive materials that will arise from the decommissioning activities. To limit the total decommissioning costs, and especially the costs associated to radioactive waste management, two strategies have been developed in order to manage a part of activated concrete as candidate for free release with a certain decay period or as candidate for conventional landfill. Both strategies will have to be further detailed and discussed with the competent Authorities to ensure they can actually be implemented. (authors)

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DOE OSTI2013

Impact of Construction Waste Disposal Charging Scheme on work practices at construction sites in Hong Kong

Highlights: Black-Right-Pointing-Pointer A significant reduction of construction waste was achieved at the first 3 years of CWDCS implementation. Black-Right-Pointing-Pointer However, the reduction cannot be sustained. Black-Right-Pointing-Pointer Implementation of the CWDCS has generated positive effects in waste reduction by all main trades. - Abstract: Waste management in the building industry in Hong Kong has become an important environmental issue. Particularly, an increasing amount of construction and demolition (C and D) waste is being disposed at landfill sites. In order to reduce waste generation and encourage reuse and recycling, the Hong Kong Government has implemented the Construction Waste Disposal Charging Scheme (CWDCS) to levy charges on C and D waste disposal to landfills. In order to provide information on the changes in reducing waste generation practice among construction participants in various work trades, a study was conducted after 3 years of implementation of the CWDCS via a structured questionnaire survey in the building industry in Hong Kong. The study result has revealed changes with work flows of the major trades as well as differentiating the levels of waste reduced. Three building projects in the public and private sectors were selected as case studies to demonstrate the changes in work flows and the reduction of waste achieved. The research findings reveal that a significant reduction of construction waste was achieved at the first 3 years (2006-2008) of CWDCS implementation. However, the reduction cannot be sustained. The major trades have been influenced to a certain extent by the implementation of the CWDCS. Slight improvement in waste management practices was observed, but reduction of construction waste in the wet-finishing and dry-finishing trades has undergone little improvement. Implementation of the CWDCS has not yet motivated subcontractors to change their methods of construction so as to reduce C and D waste.

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DOE OSTI2013

When Is the Simple Radiotoxicity Approach Useful for Advanced Fuel Cycle System Assessments Given the Existence of Complex Performance Dose Assessments?

Engineers often face the general question of which approximations are appropriate for a given analytical task. In particular, when is a simpler model useful if a more complex model also exists? This paper explores this question in the domain of radiotoxicity relative to geologic disposal performance dose assessments. Criterion 1 requires that the simpler approach, radiotoxicity, must be calculated correctly. The concept of ingestion radiotoxic inventories is analogous to the inventory of toxic chemicals in other industries. From a decision analysis perspective, it is also somewhat analogous to the nuclear reactor safety concept of “passive safety.” This paper explains some of the issues in calculating radiotoxicity, motivated by the author’s observations of errors in the literature: not accounting for radioactive progeny, misunderstanding natural “ore,” and focusing on transuranic (TRU) isotopes without adequate attention to actinide decay products. For example, Th/233U fuel cycles do have lower amounts of TRU isotopes than U/239Pu fuel cycles, but that does not necessarily mean lower long-term hazard. Criterion 2 requires that the uncertainties in the more complex approach, performance dose assessments, must raise issues for the assessments’ intended purposes—in which case, radiotoxic inventory may be of assistance until those issues are resolved. Performance dose assessments were developed for, and are legally the way to show, compliance with regulations, but the uncertainties are large. Less obvious is the degree to which dose assessments are applicable to other purposes—comparing fuel cycle options prior to site selection and showing the safety of a fuel cycle and waste management approach to the public. In the last sense especially, performance dose assessments are analogous to probabilistic risk assessments for nuclear reactor safety. The United States lacks a selected consensus site, selected fuel cycle approach (direct disposal versus recycling), and selected waste form. Thus, the paper does not intend to discuss all the issues with performance dose assessments but rather intends to focus on only those performance dose uncertainties that raise issues when comparing fuel cycles. Uncertainties associated with whether a generic geological environment is attractive or a specific location meets requirements are beyond the scope of this paper. Ingestion radiotoxicity correlates with heat, gamma, and inhalation radiotoxicity. Thus, options that are relatively high in ingestion radiotoxicity tend to be high in other parameters. Therefore, reduction in ingestion radiotoxicity means both that the potential source term for release is lower but also that one driving force for release (heat) is also lower. However, the most important time frames differ as heat is mainly an issue in decades and centuries after reactor discharge, but ingestion radiotoxicity is mainly an issue during longer time periods. Ingestion radiotoxicity points to the importance of actinides in long-term waste management, followed by specific fission products such as 99Tc, 129I, 93Zr, 135Cs, and 79Se.

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DOE OSTI2021

FY2020 performance assessment annual review for the E-area low-level waste facility

The Savannah River Site (SRS) E-Area Low-Level Waste Facility (ELLWF) consists of six types of disposal units described in the Performance Assessment (PA) (WSRC, 2008): Low Activity Waste Vault (LAWV), Intermediate Level Vault (ILV), Trenches [Slit Trenches (STs), Engineered Trenches (ETs), and Component-in-Grout (CIG) Trenches], and Naval Reactor Component Disposal Areas (NRCDAs). The ELLWF is a part of the Solid Waste Management Facility (SWMF). SWMF is managed and operated by the SRS Management and Operations prime contractor, Savannah River Nuclear Solutions (SRNS). Within SRNS, the Solid Waste Management (SWM) organization is responsible for operating the SWMF, and the Savannah River National Laboratory (SRNL) is the technical agency responsible for preparing and maintaining the PA. SWMF operations have been performed at SRS since 1952. The mission of the SWMF is to provide storage, processing, disposal, and shipment of radioactive, hazardous, and mixed waste. The SWMF is committed to treat, store, and dispose of these waste products in a manner that protects the environment and the health and safety of the facility worker, the co-located worker, and the offsite general public. Wastes handled in the SWMF include low level waste, transuranic waste, hazardous waste, Toxic Substances Control Act waste, and mixed waste (containing both hazardous and radioactive constituents). The FY2020 PA Annual Review for the ELLWF affirms that the disposal facility continued to operate within the bounds of the current PA and Composite Analysis (CA) baseline and the subsequent SA’s and satisfied all the requirements, conditions, and limitations identified in the 2008 DAS (DOE 2008a), RWMB SRNL_STI-2020-00588 Revision 0 vi (McGill, 2020), and ELLWF Low-Level Waste Acceptance Criteria (SRS-1S, 2014). This annual review affirms that the supporting studies performed in FY2020 do not alter the conclusions of the ELLWF PA (WSRC, 2008) and that there is a reasonable expectation that the ELLWF will meet the performance objectives delineated in DOE Manual 435.1-1 (DOE 2011)

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DOE OSTI2013

German Support Program for Retrieval and Safe Storage of Disused Radioactive Sealed Sources in Ukraine - 13194

The German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (BMU) on behalf of the Government of the Federal Republic of Germany supports the State Nuclear Regulatory Inspectorate of Ukraine (SNRIU) in enhancement of nuclear safety and radiation protection and strengthening of the physical protection. One of the main objectives of the agreement concluded by these parties in 2008 was the retrieval and safe interim storage of disused orphan high radioactive sealed sources in Ukraine. At present, the Ukrainian National Registry does not account all high active radiation sources but only for about 70 - 80 %. GRS in charge of BMU to execute the program since 2008 concluded subcontracts with the waste management and interim storage facilities RADON at different regions in Ukraine as well with the waste management and interim storage facility IZOTOP at Kiev. Below selected examples of removal of high active Co-60 and Cs-137 sources from irradiation facilities at research institutes are described. By end of 2012 removal and safe interim storage of 12.000 disused radioactive sealed sources with a total activity of more than 5,7.10{sup 14} Bq was achieved within the frame of this program. The German support program will be continued up to the end of 2013 with the aim to remove and safely store almost all disused radioactive sealed sources in Ukraine. (authors)

07 ISOTOPE AND RADIATION SOURCES↗

NASA NTRS1977

Space station systems analysis study. Part 2, Volume 3: Appendixes, Book 1. Program requirements documentation

The objective elements representative of the kinds of space activities that will be supported by the space construction base (SCB) are discussed in (1) a brief mission overview including the primary purpose and general objectives; (2) descriptions of the processes involved (where applicable), the mission hardware, the principal activities to be undertaken, the test requirements, and the principal tests; and (3) the SCB requirements including such items as special devices (e.g., fabrication modules, assembly or construction fixtures, cranes, and airlocks), power, data management and communications, waste management, environmental control, safety, and logistics. Each program option is then described in terms of the objective elements it supports, its orbit, the general makeup of the SCB, the transportation approach, and the program schedule goals. The specific requirements that are imposed on the SCB in order to support program option L are given.

Source record↗

NASA NTRS1990

Environmental Control and Life Support System

Viewgraphs on the Environmental Control and Life Support System (ECLSS) for the space station are presented. The ECLSS is divided into six subsystems: temperature and humidity control (THC), atmosphere control and supply (ACS), atmosphere revitalization (AR), fire detection and suppression (FDS), water recovery management (WRM), and waste management (WM). Topics covered include: ECLSS subsystem functions; ECLSS distributed system; ECLSS functional distribution; CO2 removal; CO2 reduction; oxygen generation; urine processor; and potable water recovery.

Ray, Charles↗

NASA NTRS2004

Water for Two Worlds: Designing Terrestrial Applications for Exploration-class Sanitation Systems

At the United Nations Millennium Summit in September of 2000, the world leaders agreed on an ambitious agenda for reducing poverty and improving lives: the Millennium Development Goals (MDGs), a list of issues they consider highly pernicious, threatening to human welfare and, thereby, to global security and prosperity. Among the eight goals are included fundamental human needs such as the eradication of extreme poverty and hunger, the promotion of gender equality, the reduction of child mortality and improvement of maternal health, and ensuring the sustainability of our shared environment. In order to help focus the efforts to meet these goals, the United Nations (UN) has established a set of eighteen concrete targets, each with an associated schedule. Among these is Target 10: "By 2015, reduce by half the proportion of people without access to safe drinking water." A closely related target of equal dignity was agreed at the World Summit on Sustainable Development (Johannesburg, September 2002): "By 2015, reduce by half the proportion of people without access to basic sanitation." One of the greatest successes in the development of Exploration-class technologies for closed-loop, sustainable support of long-duration human space missions has been the work both ESA and NASA have done in bioregenerative water reclamation (WRS), and secondarily, in solid-waste management. Solid-waste and WRS systems tend to be combined in the commercial world into the field of sanitation, although as we will see, the most essential principles of sustainable terrestrial sanitation actually insist upon the separation of solid and liquid excreta. Seeing the potential synergy between the space program ALS technologies developed for Mars and the urgent needs of hundreds of millions of people for secure access to clean water here on Earth, we set out to organize the adaptation of these technologies to help the United Nations Development Programme (UNDP) meet Target 10. In this paper, we will summarize the issues and results of the first "Water for Two Worlds" summit held in January of this year, describe,the status of the sustainable sanitation systems that are on the table for adaptation to widespread terrestrial use, and present fundamental strategies for forward work.

Adams, Constance↗

NASA NTRS2009

International Space Station United States Laboratory Module Water Recovery Management Subsystem Verification from Flight 5A to Stage ULF2

The International Space Station (ISS) Environmental Control and Life Support (ECLS) system comprises of seven subsystems: Atmosphere Control and Supply (ACS), Atmosphere Revitalization (AR), Fire Detection and Suppression (FDS), Temperature and Humidity Control (THC), Vacuum System (VS), Water Recovery and Management (WRM), and Waste Management (WM). This paper provides a summary of the nominal operation of the United States (U.S.) Laboratory Module WRM design and detailed element methodologies utilized during the Qualification phase of the U.S. Laboratory Module prior to launch and the Qualification of all of the modification kits added to it from Flight 5A up and including Stage ULF2.

Williams, David E.↗

NASA NTRS2012

NASA Advanced Life Support Technology Testing and Development

Prior to 2010, NASA's advanced life support research and development was carried out primarily under the Exploration Life Support Project of NASA's Exploration Systems Mission Directorate. In 2011, the Exploration Life Support Project was merged with other projects covering Fire Prevention/Suppression, Radiation Protection, Advanced Environmental Monitoring and Control, and Thermal Control Systems. This consolidated project was called Life Support and Habitation Systems, which was managed under the Exploration Systems Mission Directorate. In 2012, NASA re-organized major directorates within the agency, which eliminated the Exploration Systems Mission Directorate and created the Office of the Chief Technologist (OCT). Life support research and development is currently conducted within the Office of the Chief Technologist, under the Next Generation Life Support Project, and within the Human Exploration Operation Missions Directorate under several Advanced Exploration System projects. These Advanced Exploration Systems projects include various themes of life support technology testing, including atmospheric management, water management, logistics and waste management, and habitation systems. Food crop testing is currently conducted as part of the Deep Space Habitation (DSH) project within the Advanced Exploration Systems Program. This testing is focused on growing salad crops that could supplement the crew's diet during near term missions.

Wheeler, Raymond M.↗

DOE OSTI2013

Four Years of Practical Arrangements between IAEA and Moscow SIA 'Radon': Preliminary Results - 13061

The International Education Training Centre (IETC) at Moscow State Unitary Enterprise Scientific and Industrial Association 'Radon' (SIA 'Radon'), in co-operation with the International Atomic Energy Agency (IAEA), has developed expertise and provided training to waste management personnel for the last 15 years. Since 1997, the educational system of the enterprise with the support of the IAEA has acquired an international character: more than 470 experts from 35 countries- IAEA Member States completed the professional development. Training is conducted at various thematic courses or fellowships for individual programs and seminars on IAEA technical projects. In June 2008 a direct agreement (Practical Arrangements) was signed between SIA 'Radon' and the IAEA on cooperation in the field of development of new technologies, expert's advice to IAEA Member States, and, in particular, the training of personnel in the field of radioactive waste management (RWM), which opens up new perspectives for fruitful cooperation of industry professionals. The paper summarizes the current experience of the SIA 'Radon' in the organization and implementation of the IAEA sponsored training and others events and outlines some of strategic educational elements, which IETC will continue to pursue in the coming years. (authors)

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DOE OSTI2016

Approaches for Communicating Technical Information - 16012

Projects within the nuclear industry are generally complex and associated with high hazards. To achieve success there is often a necessity to apply innovation or adopt longer term strategies and solutions. Because of these long timescales and the fact that some approaches revolve around allowing natural radioactive decay to take place prior to visible action, the industry is sometimes perceived to be technically unable to make progress with its environmental and waste management obligations. Work within the industry additionally takes on a high profile and invariably creates greater levels of anxiety and mistrust in the eyes of stakeholders than comparable projects from non-nuclear related industries. Many aspects of the industry are still seen as secretive, environmentally detrimental and 'risky' and all components of the nuclear life-cycle are therefore open to external scrutiny. Although communication and engagement has increased greatly over the years, especially in developed countries, there is still room for improvement in this field. Such improvement might relate to the frequency and level of engagement, the subject matter or the actual process itself. Communication with stakeholders is required throughout the various phases of the nuclear lifecycle whether the activity relates to mining/milling of uranium, fuel production, operational plant activities, decommissioning, remediation or waste management. The concerns and aspirations of stakeholders during these different activities will vary but need to be adequately addressed. Some organisations now have a basic engagement program and convince themselves that they are carrying out true engagement. But just ticking a box to say that an engagement program is in place does not provide evidence of its appropriateness or success as on many occasions' organisations might still not understand how to adequately engage and communicate technical information. It is not always the information we choose to communicate but that which might be withheld that is often perceived to be most relevant to the stakeholder community. Communicating technical information isn't as straightforward as it sounds, but still has to be undertaken, otherwise trust, understanding and acceptance of chosen options will not be achieved. I utilise what I call the 'ten principles of engagement' which I believe can help when communicating technical Information in relation to nuclear and radiological matters. These are; 1. Develop Trust. 2. Educating people and providing information in a transparent manner. 3. Develop an engagement process that is truly a two way process. 4. Openly discuss risk perception and risk communication. 5. Never try to trivialise risk. 6. Where possible, simplify the language you use. 7. Put background and naturally occurring radioactivity into context. 8. Explain how radioactive materials are often used in everyday life. 9. Try to demonstrate that you too are a member of the public. 10.Walk the talk - Try to undertake what you wish others to undertake. Further research is being undertaken to determine if Mental Models might assist with the communication of nuclear and radiological information. A mental model is an explanation of someone's thought process about how something works in the real world. The mental model approach aims to investigate the judgment and decision-making processes of both expert and lay groups, thus allowing a comparison and visualisation of the different views to be made. It is undoubtedly worthwhile keeping a watching brief on the outcome of such research as we strive to improve our communication with the general public. The aim of this paper is to highlight some simple principles and approaches that can assist with the communication of technical information. (authors)

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DOE OSTI2017

Retention of Cr in Meta-kaolin-based geo-polymeric Materials under Oxidation and Carbonation - 17453

Alkali activated alumino-silicates, often referred to as geo-polymers, are considered promising immobilization matrices for contaminants due to their high sorption capacity, durability and low leachability. For some contaminants they may prove superior to cement pastes that are conventional immobilization materials in waste management applications. However, estimating the retention capacity of some contaminants under environmental conditions that include oxidation and carbonation and may induce a valance change, is complicated. These contaminants tend to be soluble under oxidizing condition and form precipitates under reducing conditions. Thus, contaminant retention is highly dependent on the initial oxidation state at which the metal was introduced, as well as the matrix sorption ability, ability to resist oxidation and carbonation, and the contaminant leachability. Moreover, carbonation in considered one of the most important degradation mechanisms in cementitious material, causing porosity reduction and significant changes in contaminant leachability, however, geo-polymers have considerably lower Ca content relative to cements, or none, and the effect of carbonation on these pastes is less clear. Thus, contaminant release mechanisms and rates must be estimated based upon exposure to various atmospheres appropriate to waste management applications. In this study we aim to estimate the sorption capacity, and leachability of Cr from a meta-kaolin based geo-polymer, doped with Cr, as a function of its oxidation state and carbonation. Cr has a high valance range from +6 to 0 similar to Tc, and is used as its simulant in the current study. Sodium dichromate was used as an oxidized source metal material. To induce reducing conditions, ascorbic acid was added except for experimental control cases. The samples were aged under N{sub 2}, 98% N{sub 2} + 2% CO{sub 2}, CO{sub 2} deficient air and air environments under constant relative humidity. Following aging, samples were subject to equilibrium leaching as a function of pH (EPA Method 1313) and monolith mass transport rate testing (EPA Method 1315). Mass balance calculations, based on the results of a pH dependent leaching test, have shown that oxidized Cr samples lost 85-95% of their Cr content, whereas, the reduced Cr samples lost only 20% of their Cr content. On the other hand, the leachability of Si and Al is much higher in the reduced-Cr samples then in the samples with oxidized Cr, and their natural pH is up to 2.5 pH units lower than that of the oxidizing cases. Thus, we conclude that the combination of the reducing agent and the spike chemistry influence the matrix formation. Sample aging have not resulted in any significant change in the Cr-leaching behavior of the oxidizing matrices in the pH dependent leaching test, although a significant decrease in the natural pH, of 1.5 pH unit, was observed upon exposure to elevated CO{sub 2} levels (2%), probably due to the formation of Na-carbonate species. The pH and leaching behavior of the reduced Cr samples under the various aging conditions have not yielded significant variation either in their natural pH or in their leaching behavior. (authors)

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DOE OSTI2017

Modular Platforms for Advanced Inspection, Locomotion, and Manipulation - 17150

Robots can provide remote access, manipulation, and inspection capabilities to augment human workers and improve safety in potentially dangerous decommissioning, radioactive waste management, and emergency response operations. However, such activities may require navigating challenging and unstructured environments, such as those with uneven terrain, obstacles, or loose debris. This remains a difficult task, even for modern robots. What's more, a robot's physical design can inhibit it from accessing hard-to-reach areas such as the tight spaces around, underneath, or inside piping and equipment. To address these challenges, we have developed a series of physically robust hardware modules that can be configured into a variety of robot morphologies, specialized to support different operational needs. Each hardware module consists of a number of onboard sensors and a high performance actuator with a series elastic element to sense and control interaction forces for improved locomotion and manipulation. Using this hardware, we have designed several robotic platforms that support the access, manipulation, and inspection requirements of decommissioning and radioactive waste management. To highlight current capabilities and potential opportunities for technological improvement, we present the outcomes from field demonstrations of our modular platforms at the Office of Environmental Management's Science of Safety Portsmouth Gaseous Diffusion Plant Robotics Challenge. Specifically, results include a serpentine robot climbing vertical structures such as pipes, posts, and supports to demonstrate advanced inspection. Additionally, we discuss field trials of a similar modular configuration that yields a highly dexterous manipulator arm and camera system capable of adding manipulation and inspection functionality to existing structures. Results are presented from inspection tasks in which the manipulator is installed on another mobile robotic platform. Finally, we show our hardware modules can be reconfigured into platforms capable of withstanding significant impacts and of alternative means of locomotion, as may be required to cross terrain too challenging for traditional wheeled robots. Results describe the performance of a hexapod robot that uses proprioceptive feedback to locomote in outdoor trials reminiscent of emergency response conditions. (authors)

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