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Sample records for high-level alumina nuclear

  1. High level nuclear waste

    SciTech Connect

    Crandall, J L

    1980-01-01

    The DOE Division of Waste Products through a lead office at Savannah River is developing a program to immobilize all US high-level nuclear waste for terminal disposal. DOE high-level wastes include those at the Hanford Plant, the Idaho Chemical Processing Plant, and the Savannah River Plant. Commercial high-level wastes, for which DOE is also developing immobilization technology, include those at the Nuclear Fuel Services Plant and any future commercial fuels reprocessing plants. The first immobilization plant is to be the Defense Waste Processing Facility at Savannah River, scheduled for 1983 project submission to Congress and 1989 operation. Waste forms are still being selected for this plant. Borosilicate glass is currently the reference form, but alternate candidates include concretes, calcines, other glasses, ceramics, and matrix forms.

  2. Development of polyphase ceramics for the immobilization of high-level Defense nuclear waste

    SciTech Connect

    Morgan, P.E.D.; Harker, A.B.; Clarke, D.R.; Flintoff, J.J.; Shaw, T.M.

    1983-02-25

    The report contains two major sections: Section I - An Improved Polyphase Ceramic for High-Level Defense Nucleation Waste reports the work conducted on titanium-silica based ceramics for immobilizing Savannah River Plant waste. Section II - Formulation and Processing of Alumina Based Ceramic Nuclear Waste Forms describes the work conducted on developing a generic alumina and alumina-silica based ceramic waste form capable of immobilizing any nuclear waste with a high aluminum content. Such wastes include the Savannah River Plant wastes, Hanford neutralized purex wastes, and Hanford N-Reactor acid wastes. The design approach and process technology in the two reports demonstrate how the generic high waste loaded ceramic form can be applied to a broad range of nuclear waste compositions. The individual sections are abstracted and indexed separately.

  3. Materials Science of High-Level Nuclear Waste Immobilization

    SciTech Connect

    Weber, William J.; Navrotsky, Alexandra; Stefanovsky, S. V.; Vance, E. R.; Vernaz, Etienne Y.

    2009-01-09

    With the increasing demand for the development of more nuclear power comes the responsibility to address the technical challenges of immobilizing high-level nuclear wastes in stable solid forms for interim storage or disposition in geologic repositories. The immobilization of high-level nuclear wastes has been an active area of research and development for over 50 years. Borosilicate glasses and complex ceramic composites have been developed to meet many technical challenges and current needs, although regulatory issues, which vary widely from country to country, have yet to be resolved. Cooperative international programs to develop advanced proliferation-resistant nuclear technologies to close the nuclear fuel cycle and increase the efficiency of nuclear energy production might create new separation waste streams that could demand new concepts and materials for nuclear waste immobilization. This article reviews the current state-of-the-art understanding regarding the materials science of glasses and ceramics for the immobilization of high-level nuclear waste and excess nuclear materials and discusses approaches to address new waste streams.

  4. Disposal of high-level nuclear waste in space

    NASA Astrophysics Data System (ADS)

    Coopersmith, Jonathan

    1992-08-01

    A solution of launching high-level nuclear waste into space is suggested. Disposal in space includes solidifying the wastes, embedding them in an explosion-proof vehicle, and launching it into earth orbit, and then into a solar orbit. The benefits of such a system include not only the safe disposal of high-level waste but also the establishment of an infrastructure for large-scale space exploration and development. Particular attention is given to the wide range of technical choices along with the societal, economic, and political factors needed for success.

  5. Case for retrievable high-level nuclear waste disposal

    USGS Publications Warehouse

    Roseboom, Eugene H., Jr.

    1994-01-01

    Plans for the nation's first high-level nuclear waste repository have called for permanently closing and sealing the repository soon after it is filled. However, the hydrologic environment of the proposed site at Yucca Mountain, Nevada, should allow the repository to be kept open and the waste retrievable indefinitely. This would allow direct monitoring of the repository and maintain the options for future generations to improve upon the disposal methods or use the uranium in the spent fuel as an energy resource.

  6. Socioeconomic studies of high-level nuclear waste disposal.

    PubMed

    White, G F; Bronzini, M S; Colglazier, E W; Dohrenwend, B; Erikson, K; Hansen, R; Kneese, A V; Moore, R; Page, E B; Rappaport, R A

    1994-11-01

    The socioeconomic investigations of possible impacts of the proposed repository for high-level nuclear waste at Yucca Mountain, Nevada, have been unprecedented in several respects. They bear on the public decision that sooner or later will be made as to where and how to dispose permanently of the waste presently at military weapons installations and that continues to accumulate at nuclear power stations. No final decision has yet been made. There is no clear precedent from other countries. The organization of state and federal studies is unique. The state studies involve more disciplines than any previous efforts. They have been carried out in parallel to federal studies and have pioneered in defining some problems and appropriate research methods. A recent annotated bibliography provides interested scientists with a compact guide to the 178 published reports, as well as to relevant journal articles and related documents. PMID:7971963

  7. Socioeconomic studies of high-level nuclear waste disposal.

    PubMed Central

    White, G F; Bronzini, M S; Colglazier, E W; Dohrenwend, B; Erikson, K; Hansen, R; Kneese, A V; Moore, R; Page, E B; Rappaport, R A

    1994-01-01

    The socioeconomic investigations of possible impacts of the proposed repository for high-level nuclear waste at Yucca Mountain, Nevada, have been unprecedented in several respects. They bear on the public decision that sooner or later will be made as to where and how to dispose permanently of the waste presently at military weapons installations and that continues to accumulate at nuclear power stations. No final decision has yet been made. There is no clear precedent from other countries. The organization of state and federal studies is unique. The state studies involve more disciplines than any previous efforts. They have been carried out in parallel to federal studies and have pioneered in defining some problems and appropriate research methods. A recent annotated bibliography provides interested scientists with a compact guide to the 178 published reports, as well as to relevant journal articles and related documents. PMID:7971963

  8. Spent nuclear fuel project high-level information management plan

    SciTech Connect

    Main, G.C.

    1996-09-13

    This document presents the results of the Spent Nuclear Fuel Project (SNFP) Information Management Planning Project (IMPP), a short-term project that identified information management (IM) issues and opportunities within the SNFP and outlined a high-level plan to address them. This high-level plan for the SNMFP IM focuses on specific examples from within the SNFP. The plan`s recommendations can be characterized in several ways. Some recommendations address specific challenges that the SNFP faces. Others form the basis for making smooth transitions in several important IM areas. Still others identify areas where further study and planning are indicated. The team`s knowledge of developments in the IM industry and at the Hanford Site were crucial in deciding where to recommend that the SNFP act and where they should wait for Site plans to be made. Because of the fast pace of the SNFP and demands on SNFP staff, input and interaction were primarily between the IMPP team and members of the SNFP Information Management Steering Committee (IMSC). Key input to the IMPP came from a workshop where IMSC members and their delegates developed a set of draft IM principles. These principles, described in Section 2, became the foundation for the recommendations found in the transition plan outlined in Section 5. Availability of SNFP staff was limited, so project documents were used as a basis for much of the work. The team, realizing that the status of the project and the environment are continually changing, tried to keep abreast of major developments since those documents were generated. To the extent possible, the information contained in this document is current as of the end of fiscal year (FY) 1995. Programs and organizations on the Hanford Site as a whole are trying to maximize their return on IM investments. They are coordinating IM activities and trying to leverage existing capabilities. However, the SNFP cannot just rely on Sitewide activities to meet its IM requirements

  9. Process for solidifying high-level nuclear waste

    DOEpatents

    Ross, Wayne A.

    1978-01-01

    The addition of a small amount of reducing agent to a mixture of a high-level radioactive waste calcine and glass frit before the mixture is melted will produce a more homogeneous glass which is leach-resistant and suitable for long-term storage of high-level radioactive waste products.

  10. Corrosion issues in high-level nuclear waste containers

    NASA Astrophysics Data System (ADS)

    Asl, Samin Sharifi

    In this dissertation different aspects of corrosion and electrochemistry of copper, candidate canister material in Scandinavian high-level nuclear waste disposal program, including the thermodynamics and kinetics of the reactions that are predicted to occur in the practical system have been studied. A comprehensive thermodynamic study of copper in contact with granitic groundwater of the type and composition that is expected in the Forsmark repository in Sweden has been performed. Our primary objective was to ascertain whether copper would exist in the thermodynamically immune state in the repository, in which case corrosion could not occur and the issue of corrosion in the assessment of the storage technology would be moot. In spite of the fact that metallic copper has been found to exist for geological times in granitic geological formations, copper is well-known to be activated from the immune state to corrode by specific species that may exist in the environment. The principal activator of copper is known to be sulfur in its various forms, including sulfide (H2S, HS-, S2-), polysulfide (H2Sx, HSx -, Sx 2-), poly sulfur thiosulfate ( SxO3 2-), and polythionates (SxO6 2-). A comprehensive study of this aspect of copper chemistry has never been reported, and yet an understanding of this issue is vital for assessing whether copper is a suitable material for fabricating canisters for the disposal of HLNW. Our study identifies and explores those species that activate copper; these species include sulfur-containing entities as well as other, non-sulfur species that may be present in the repository. The effects of temperature, solution pH, and hydrogen pressure on the kinetics of the hydrogen electrode reaction (HER) on copper in borate buffer solution have been studied by means of steady-state polarization measurements, including electrochemical impedance spectroscopy (EIS). In order to obtain electrokinetic parameters, such as the exchange current density and the

  11. Modern Alchemy: Solidifying high-level nuclear waste

    SciTech Connect

    Newton, C.C.

    1997-07-01

    The U.S. Department of Energy is putting a modern version of alchemy to work to produce an answer to a decades-old problem. It is taking place at the Savannah River Site (SRS) in Aiken, South Carolina and at the West Valley Demonstration Project (WVDP) near Buffalo, New York. At both locations, contractor Westinghouse Electric Corporation is applying technology that is turning liquid high-level radioactive waste (HLW) into a stabilized, durable glass for safer and easier management. The process is called vitrification. SRS and WVDP are now operating the nation`s first full-scale HLW vitrification plants.

  12. New Generation Nuclear Plant -- High Level Functions and Requirements

    SciTech Connect

    J. M. Ryskamp; E. J. Gorski; E. A. Harvego; S. T. Khericha; G. A. Beitel

    2003-09-01

    This functions and requirements (F&R) document was prepared for the Next Generation Nuclear Plant (NGNP) Project. The highest-level functions and requirements for the NGNP preconceptual design are identified in this document, which establishes performance definitions for what the NGNP will achieve. NGNP designs will be developed based on these requirements by commercial vendor(s).

  13. Why consider subseabed disposal of high-level nuclear waste

    SciTech Connect

    Heath, G. R.; Hollister, C. D.; Anderson, D. R.; Leinen, M.

    1980-01-01

    Large areas of the deep seabed warrant assessment as potential disposal sites for high-level radioactive waste because: (1) they are far from seismically and tectonically active lithospheric plate boundaries; (2) they are far from active or young volcanos; (3) they contain thick layers of very uniform fine-grained clays; (4) they are devoid of natural resources likely to be exploited in the forseeable future; (5) the geologic and oceanographic processes governing the deposition of sediments in such areas are well understood, and are remarkably insensitive to past oceanographic and climatic changes; and (6) sedmentary records of tens of millions of years of slow, uninterrupted deposition of fine grained clay support predictions of the future stability of such sites. Data accumulated to date on the permeability, ion-retardation properties, and mechanical strength of pelagic clay sediments indicate that they can act as a primary barrier to the escape of buried nuclides. Work in progress should determine within the current decade whether subseabed disposal is environmentally acceptable and technically feasible, as well as address the legal, political and social issues raised by this new concept.

  14. Inspection and evaluation of Nuclear Fuel Services high-level waste storage system, program plan

    NASA Astrophysics Data System (ADS)

    1980-01-01

    Information concerning the condition of the high-level waste tanks at the Western New York State Nuclear Service center near West Valley, New York is presented. This information is to be used in evaluating the safety of continued storage and in the development of alternatives for final disposition of the high-level waste.

  15. 75 FR 61228 - Board Meeting: Technical Lessons Gained From High-Level Nuclear Waste Disposal Efforts

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-04

    ... REVIEW BOARD Board Meeting: Technical Lessons Gained From High-Level Nuclear Waste Disposal Efforts... 1987, the U.S. Nuclear Waste Technical Review Board will meet in Dulles, Virginia, on October 26, 2010... technical issues and to review the technical validity of DOE activities related to implementing the...

  16. Workshop on the role of natural analogs in geologic disposal of high-level nuclear waste

    SciTech Connect

    Murphy, W.M.; Kovach, L.A.

    1995-09-01

    A workshop on the Role of Natural Analogs in Geologic Disposal of High-Level Nuclear Waste (HLW) was held in San Antonio, Texas, on July 22-25, 1991. It was sponsored by the US Nuclear Regulatory Commission (NRC) and the Center for Nuclear Waste Regulatory Analyses (CNWRA). Invitations to the workshop were extended to a large number of individuals with a variety of technical and professional interests related to geologic disposal of nuclear waste and natural analog studies. The objective of the workshop was to examine the role of natural analog studies in performance assessment, site characterization, and prioritization of research related to geologic disposal of HLW.

  17. CHEMICAL DECOMPOSITION OF HIGH-LEVEL NUCLEAR WASTE STORAGE/DISPOSAL GLASSES UNDER IRRADIATION

    EPA Science Inventory

    The Offices of Energy Research and Environmental Management are immediately concerned with the development of storage/immobilization media for high-level nuclear wastes and excess weapons plutonium. These media must be stable and free of risk to the public or to the environment f...

  18. Chem I Supplement. Chemistry Related to Isolation of High-Level Nuclear Waste.

    ERIC Educational Resources Information Center

    Hoffman, Darleane C.; Choppin, Gregory R.

    1986-01-01

    Discusses some of the problems associated with the safe disposal of high-level nuclear wastes. Describes several waste disposal plans developed by various nations. Outlines the multiple-barrier concept of isolation in deep geological questions associated with the implementation of such a method. (TW)

  19. Lead iron phosphate glass as a containment medium for disposal of high-level nuclear waste

    DOEpatents

    Boatner, Lynn A.; Sales, Brian C.

    1989-01-01

    Lead-iron phosphate glasses containing a high level of Fe.sub.2 O.sub.3 for use as a storage medium for high-level radioactive nuclear waste. By combining lead-iron phosphate glass with various types of simulated high-level nuclear waste, a highly corrosion resistant, homogeneous, easily processed glass can be formed. For corroding solutions at 90.degree. C., with solution pH values in the range between 5 and 9, the corrosion rate of the lead-iron phosphate nuclear waste glass is at least 10.sup.2 to 10.sup.3 times lower than the corrosion rate of a comparable borosilicate nuclear waste glass. The presence of Fe.sub.2 O.sub.3 in forming the lead-iron phosphate glass is critical. Lead-iron phosphate nuclear waste glass can be prepared at temperatures as low as 800.degree. C., since they exhibit very low melt viscosities in the 800.degree. to 1050.degree. C. temperature range. These waste-loaded glasses do not readily devitrify at temperatures as high as 550.degree. C. and are not adversely affected by large doses of gamma radiation in H.sub.2 O at 135.degree. C. The lead-iron phosphate waste glasses can be prepared with minimal modification of the technology developed for processing borosilicate glass nuclear wasteforms.

  20. Lead-iron phosphate glass as a containment medium for the disposal of high-level nuclear wastes

    DOEpatents

    Boatner, L.A.; Sales, B.C.

    1984-04-11

    Disclosed are lead-iron phosphate glasses containing a high level of Fe/sub 2/O/sub 3/ for use as a storage medium for high-level radioactive nuclear waste. By combining lead-iron phosphate glass with various types of simulated high-level nuclear waste

  1. Development of Ceramic Waste Forms for High-Level Nuclear Waste Over the Last 30 Years

    SciTech Connect

    Vance, Eric

    2007-07-01

    Many types of ceramics have been put forward for immobilisation of high-level waste (HLW) from reprocessing of nuclear power plant fuel or weapons production. After describing some historical aspects of waste form research, the essential features of the chemical design and processing of these different ceramic types will be discussed briefly. Given acceptable laboratory and long-term predicted performance based on appropriately rigorous chemical design, the important processing parameters are mostly waste loading, waste throughput, footprint, offgas control/minimization, and the need for secondary waste treatment. It is concluded that the 'problem of high-level nuclear waste' is largely solved from a technical point of view, within the current regulatory framework, and that the main remaining question is which technical disposition method is optimum for a given waste. (author)

  2. Ceramic process and plant design for high-level nuclear waste immobilization

    SciTech Connect

    Grantham, L.F.; McKisson, R.L.; De Wames, R.E.; Guon, J.; Flintoff, J.F.; McKenzie, D.E.

    1983-01-01

    In the last 3 years, significant advances in ceramic technology for high-level nuclear waste solidification have been made. Product quality in terms of leach-resistance, compositional uniformity, structural integrity, and thermal stability promises to be superior to borosilicate glass. This paper addresses the process effectiveness and preliminary designs for glass and ceramic immobilization plants. The reference two-step ceramic process utilizes fluid-bed calcination (FBC) and hot isostatic press (HIP) consolidation. Full-scale demonstration of these well-developed processing steps has been established at DOE and/or commercial facilities for processing radioactive materials. Based on Savannah River-type waste, our model predicts that the capital and operating cost for the solidification of high-level nuclear waste is about the same for the ceramic and glass options. However, when repository costs are included, the ceramic option potentially offers significantly better economics due to its high waste loading and volume reduction. Volume reduction impacts several figures of merit in addition to cost such as system logistics, storage, transportation, and risk. The study concludes that the ceramic product/process has many potential advantages, and rapid deployment of the technology could be realized due to full-scale demonstrations of FBC and HIP technology in radioactive environments. Based on our finding and those of others, the ceramic innovation not only offers a viable backup to the glass reference process but promises to be a viable future option for new high-level nuclear waste management opportunities.

  3. What are Spent Nuclear Fuel and High-Level Radioactive Waste ?

    SciTech Connect

    DOE

    2002-12-01

    Spent nuclear fuel and high-level radioactive waste are materials from nuclear power plants and government defense programs. These materials contain highly radioactive elements, such as cesium, strontium, technetium, and neptunium. Some of these elements will remain radioactive for a few years, while others will be radioactive for millions of years. Exposure to such radioactive materials can cause human health problems. Scientists worldwide agree that the safest way to manage these materials is to dispose of them deep underground in what is called a geologic repository.

  4. On-site storage of high level nuclear waste: attitudes and perceptions of local residents.

    PubMed

    Bassett, G W; Jenkins-Smith, H C; Silva, C

    1996-06-01

    No public policy issue has been as difficult as high-level nuclear waste. Debates continue regarding Yucca Mountain as a disposal site, and-more generally-the appropriateness of geologic disposal and the need to act quickly. Previous research has focused on possible social, political, and economic consequences of a facility in Nevada. Impacts have been predicted to be potentially large and to emanate mainly from stigmatization of the region due to increased perceptions of risk. Analogous impacts from leaving waste at power plants have been either ignored or assumed to be negligible. This paper presents survey results on attitudes of residents in three counties where nuclear waste is currently stored. Topics include perceived risk, knowledge of nuclear waste and radiation, and impacts on jobs, tourism, and housing values from leaving waste on site. Results are similar to what has been reported for Nevada; the public is concerned about possible adverse effects from on-site storage of waste. PMID:8693158

  5. Can Sisyphus succeed? Getting U.S. high-level nuclear waste into a geological repository.

    PubMed

    North, D Warner

    2013-01-01

    The U.S. government has the obligation of managing the high-level radioactive waste from its defense activities and also, under existing law, from civilian nuclear power generation. This obligation is not being met. The January 2012 Final Report from the Blue Ribbon Commission on America's Nuclear Future provides commendable guidance but little that is new. The author, who served on the federal Nuclear Waste Technical Review Board from 1989 to 1994 and subsequently on the Board on Radioactive Waste Management of the National Research Council from 1994 to 1999, provides a perspective both on the Commission's recommendations and a potential path toward progress in meeting the federal obligation. By analogy to Sisyphus of Greek mythology, our nation needs to find a way to roll the rock to the top of the hill and have it stay there, rather than continuing to roll back down again. PMID:23311528

  6. Robotics and remote handling concepts for disposal of high-level nuclear waste

    SciTech Connect

    McAffee, Douglas; Raczka, Norman; Schwartztrauber, Keith

    1997-04-27

    This paper summarizes preliminary remote handling and robotic concepts being developed as part of the US Department of Energy's (DOE) Yucca Mountain Project. The DOE is currently evaluating the Yucca Mountain Nevada site for suitability as a possible underground geologic repository for the disposal of high level nuclear waste. The current advanced conceptual design calls for the disposal of more than 12,000 high level nuclear waste packages within a 225 km underground network of tunnels and emplacement drifts. Many of the waste packages may weigh as much as 66 tonnes and measure 1.8 m in diameter and 5.6 m long. The waste packages will emit significant levels of radiation and heat. Therefore, remote handling is a cornerstone of the repository design and operating concepts. This paper discusses potential applications areas for robotics and remote handling technologies within the subsurface repository. It also summarizes the findings of a preliminary technology survey which reviewed available robotic and remote handling technologies developed within the nuclear, mining, rail and industrial robotics and automation industries, and at national laboratories, universities, and related research institutions and government agencies.

  7. High level nuclear waste repository in salt: Sealing systems status and planning report: Draft report

    SciTech Connect

    1985-09-01

    This report documents the initial conceptual design studies for a repository sealing system for a high-level nuclear waste repository in salt. The first step in the initial design studies was to review the current design level, termed schematic designs. This review identified practicality of construction and development of a design methodology as two key issues for the conceptual design. These two issues were then investigated during the initial design studies for seal system materials, seal placement, backfill emplacement, and a testing and monitoring plan. The results of these studies have been used to develop a program plan for completion of the sealing system conceptual design. 60 refs., 26 figs., 18 tabs.

  8. Dynamic analysis and design considerations for high-level nuclear waste repositories

    SciTech Connect

    Hossain, Q.A.

    1993-09-01

    These proceedings are arranged into six broad categories: general overview of analysis and design; characterization of faulting; characterization of design ground vibratory ground motion; considerations for underground facilities; considerations for surface facilities; and guidelines for instrumentation and monitoring. Discussions are given on the relative merits and inadequacies of state-of-the-art design/analysis practices and methodologies in the seismic and dynamic analysis and design field in relation to high-level nuclear waste repositories. All papers have been processed for inclusion on the data base.

  9. Microwave energy for post-calcination treatment of high-level nuclear wastes

    SciTech Connect

    Gombert, D.; Priebe, S.J.; Berreth, J.R.

    1980-01-01

    High-level radioactive wastes generated from nuclear fuel reprocessing require treatment for effective long-term storage. Heating by microwave energy is explored in processing of two possible waste forms: (1) drying of a pelleted form of calcined waste; and (2) vitrification of calcined waste. It is shown that residence times for these processes can be greatly reduced when using microwave energy rather than conventional heating sources, without affecting product properties. Compounds in the waste and in the glass frit additives couple very well with the 2.45 GHz microwave field so that no special microwave absorbers are necessary.

  10. Four themes that underlie the high-level nuclear waste management program

    SciTech Connect

    Sprecher, W.M.

    1989-01-01

    In 1982, after years of deliberation and in response to mounting pressures from environmental, industrial, and other groups, the US Congress enacted the Nuclear Waste Policy Act (NWPA) of 1982, which was signed into law by the President in January 1983. That legislation signified a major milestone in the nation's management of high-level nuclear waste, since it represented a consensus among the nation's lawmakers to tackle a problem that had evaded solution for decades. Implementation of the NWPA has proven to be exceedingly difficult, as attested by the discord generated by the US Department of Energy's (DOE's) geologic repository and monitored retrievable storage (MRS) facility siting activities. The vision that motivated the crafters of the 1982 act became blurred as opposition to the law increased. After many hearings that underscored the public's concern with the waste management program, the Congress enacted the Nuclear Waste Policy Amendments Act of 1987 (Amendments Act), which steamlined and focused the program, while establishing three independent bodies: the MRS Review Commission, the Nuclear Waste Technical Review Board, and the Office of the Nuclear Waste Negotiator. Yet, even as the program evolves, several themes characterizing the nation's effort to solve the waste management problem continue to prevail. The first of these themes has to do with social consciousness, and the others that follow deal with technical leadership, public involvement and risk perceptions, and program conservatism.

  11. United States Program on Spent Nuclear Fuel and High-Level Radioactive Waste Management

    SciTech Connect

    Stewart, L.

    2004-10-03

    The President signed the Congressional Joint Resolution on July 23, 2002, that designated the Yucca Mountain site for a proposed geologic repository to dispose of the nation's spent nuclear fuel (SNF) and high-level radioactive waste (HLW). The United States (U.S.) Department of Energy's (DOE) Office of Civilian Radioactive Waste Management (OCRWM) is currently focusing its efforts on submitting a license application to the U.S. Nuclear Regulatory Commission (NRC) in December 2004 for construction of the proposed repository. The legislative framework underpinning the U.S. repository program is the basis for its continuity and success. The repository development program has significantly benefited from international collaborations with other nations in the Americas.

  12. Sorption of strontium on uranyl peroxide: implications for a high-level nuclear waste repository.

    PubMed

    Sureda, Rosa; Martínez-Lladó, Xavier; Rovira, Miquel; de Pablo, Joan; Casas, Ignasi; Giménez, Javier

    2010-09-15

    Strontium-90 is considered the most important radioactive isotope in the environment and one of the most frequently occurring radionuclides in groundwaters at nuclear facilities. The uranyl peroxide studtite (UO2O2 . 4H2O) has been observed to be formed in spent nuclear fuel leaching experiments and seems to have a relatively high sorption capacity for some radionuclides. In this work, the sorption of strontium onto studtite is studied as a function of time, strontium concentration in solution and pH. The main results obtained are (a) sorption is relatively fast although slower than for cesium; (b) strontium seems to be sorbed via a monolayer coverage of the studtite surface, (c) sorption has a strong dependence on ionic strength, is negligible at acidic pH, and increases at neutral to alkaline pH (almost 100% of the strontium in solution is sorbed above pH 10). These results point to uranium secondary solid phase formation on the spent nuclear fuel as an important mechanism for strontium retention in a high-level nuclear waste repository (HLNW). PMID:20638966

  13. Risk perception on management of nuclear high-level and transuranic waste storage

    SciTech Connect

    Dees, L.A.

    1994-08-15

    The Department of Energy`s program for disposing of nuclear High-Level Waste (HLW) and transuranic (TRU) waste has been impeded by overwhelming political opposition fueled by public perceptions of actual risk. Analysis of these perceptions shows them to be deeply rooted in images of fear and dread that have been present since the discovery of radioactivity. The development and use of nuclear weapons linked these images to reality and the mishandling of radioactive waste from the nations military weapons facilities has contributed toward creating a state of distrust that cannot be erased quickly or easily. In addition, the analysis indicates that even the highly educated technical community is not well informed on the latest technology involved with nuclear HLW and TRU waste disposal. It is not surprising then, that the general public feels uncomfortable with DOE`s management plans for with nuclear HLW and TRU waste disposal. Postponing the permanent geologic repository and use of Monitored Retrievable Storage (MRS) would provide the time necessary for difficult social and political issues to be resolved. It would also allow time for the public to become better educated if DOE chooses to become proactive.

  14. Should high-level nuclear waste be disposed of at geographically dispersed sites?

    SciTech Connect

    Bassett, G.W. Jr.; Hemphill, R.; Kohout, E.

    1992-07-01

    Consideration of the technical feasibility of Yucca Mountain in Nevada as the site for a high-level nuclear waste repository has led to an intense debate regarding the economic, social, and political impacts of the repository. Impediments to the siting process mean that the nuclear waste problem is being resolved by adhering to the status quo, in which nuclear waste is stored at scattered sites near major population centers. To assess the merits of alternative siting strategies--including both the permanent repository and the status quo- we consider the variables that would be included in a model designed to select (1) the optimal number of disposal facilities, (2) the types of facilities (e.g., permanent repository or monitored retrievable facility), and (3) the geographic location of storage sites. The objective function in the model is an all-inclusive measure of social cost. The intent of the exercise is not to demonstrate the superiority of any single disposal strategy; uncertainties preclude a conclusive proof of optimality for any of the disposal options. Instead, we want to assess the sensitivity of a variety of proposed solutions to variations in the physical, economic, political, and social variables that influence a siting strategy.

  15. On-site storage of high level nuclear waste: Attitudes and perceptions of local residents

    SciTech Connect

    Bassett, G.W. Jr.; Jenkins-Smith, H.C.; Silva, C.

    1996-06-01

    No public policy issue has been as difficult as high-level nuclear waste. Debates continue regarding Yucca Mountain as a disposal site, and - more generally - the appropriateness of geologic disposal and the need to act quickly. Previous research has focused on possible social, political, and economic consequences of a facility in Nevada. Impacts have been predicted to be potentially large and to emanate mainly from stigmatization of the region due to increased perceptions of risk. Analogous impacts from leaving waste at power plants have been either ignored or assumed to be negligible. This paper presents survey results on attitudes of residents in three countries where nuclear waste is currently stored. Topics include perceived risk, knowledge of nuclear waste and radiation, and impacts on jobs, tourism, and housing values from leaving waste on site. Results are similar to what has been reported for Nevada; the public is concerned about possible adverse effects from on-site storage of waste. 24 refs., 7 figs., 5 tabs.

  16. Selection of candidate canister materials for high-level nuclear waste containment in a tuff repository

    SciTech Connect

    McCright, R.D.; Weiss, H.; Juhas, M.C.; Logan, R.W.

    1983-11-01

    A repository located at Yucca Mountain at the Nevada Test Site is a potential site for permanent geological disposal of high-level nuclear waste. The repository can be located in a horizon in welded tuff, a volcanic rock, which is above the static water level at this site. The environmental conditions in this unsaturated zone are expected to be air and water vapor dominated for much of the containment period. Type 304L stainless steel is the reference material for fabricating canisters to contain the solid high-level wastes. Alternative stainless alloys are considered because of possible susceptibility of 304L to localized and stress forms of corrosion. For the reprocessed glass wastes, the canisters serve as the recipient for pouring the glass with the result that a sensitized microstructure may develop because of the times at elevated temperatures. Corrosion testing of the reference and alternative materials has begun in tuff-conditioned water and steam environments. 21 references, 8 figures, 8 tables.

  17. Instrument reliability for high-level nuclear-waste-repository applications

    SciTech Connect

    Rogue, F.; Binnall, E.P.; Armantrout, G.A.

    1983-01-31

    Reliable instrumentation will be needed to evaluate the characteristics of proposed high-level nuclear-wasted-repository sites and to monitor the performance of selected sites during the operational period and into repository closure. A study has been done to assess the reliability of instruments used in Department of Energy (DOE) waste repository related experiments and in other similar geological applications. The study included experiences with geotechnical, hydrological, geochemical, environmental, and radiological instrumentation and associated data acquisition equipment. Though this paper includes some findings on the reliability of instruments in each of these categories, the emphasis is on experiences with geotechnical instrumentation in hostile repository-type environments. We review the failure modes, rates, and mechanisms, along with manufacturers modifications and design changes to enhance and improve instrument performance; and include recommendations on areas where further improvements are needed.

  18. Strontium and Actinide Separations from High Level Nuclear Waste Solutions using Monosodium Titanate - Actual Waste Testing

    SciTech Connect

    Peters, T.B.; Barnes, M.J.; Hobbs,D.T.; Walker, D.D.; Fondeur, F.F.; Norato, M.A.; Pulmano, R.L.; Fink, S.D.

    2005-11-01

    Pretreatment processes at the Savannah River Site will separate {sup 90}Sr, alpha-emitting and radionuclides (i.e., actinides) and {sup 137}Cs prior to disposal of the high-level nuclear waste. Separation of {sup 90}Sr and alpha-emitting radionuclides occurs by ion exchange/adsorption using an inorganic material, monosodium titanate (MST). Previously reported testing with simulants indicates that the MST exhibits high selectivity for strontium and actinides in high ionic strength and strongly alkaline salt solutions. This paper provides a summary of data acquired to measure the performance of MST to remove strontium and actinides from actual waste solutions. These tests evaluated the effects of ionic strength, mixing, elevated alpha activities, and multiple contacts of the waste with MST. Tests also provided confirmation that MST performs well at much larger laboratory scales (300-700 times larger) and exhibits little affinity for desorption of strontium and plutonium during washing.

  19. High-performance gamma spectroscopy for equipment retrieval from Hanford high-level nuclear waste tanks

    NASA Astrophysics Data System (ADS)

    Troyer, Gary L.; Hillesand, K. E.; Goodwin, S. G.; Kessler, S. F.; Killian, E. W.; Legare, D.; Nelson, Joseph V., Jr.; Richard, R. F.; Nordquist, E. M.

    1999-01-01

    The cleanup of high level defense nuclear waste at the Hanford site presents several progressive challenges. Among these is the removal and disposal of various components from buried active waste tanks to allow new equipment insertion or hazards mitigation. A unique automated retrieval system at the tank provides for retrieval, high pressure washing, inventory measurement, and containment for disposal. Key to the inventory measurement is a three detector HPGe high performance gamma spectroscopy system capable of recovering data at up to ninety per cent saturation (200,000 counts per second). Data recovery is based on a unique embedded electronic pulser and specialized software to report the inventory. Each of the detectors have different shielding specified through Monte Carlo simulation with the MCNP program. This shielding provides performance over a dynamic range of eight orders of magnitude. System description, calibration issues and operational experiences are discussed.

  20. Natural geochemical analogues of the near field of high-level nuclear waste repositories

    SciTech Connect

    Apps, J.A.

    1995-09-01

    United States practice has been to design high-level nuclear waste (HLW) geological repositories with waste densities sufficiently high that repository temperatures surrounding the waste will exceed 100{degrees}C and could reach 250{degrees}C. Basalt and devitrified vitroclastic tuff are among the host rocks considered for waste emplacement. Near-field repository thermal behavior and chemical alteration in such rocks is expected to be similar to that observed in many geothermal systems. Therefore, the predictive modeling required for performance assessment studies of the near field could be validated and calibrated using geothermal systems as natural analogues. Examples are given which demonstrate the need for refinement of the thermodynamic databases used in geochemical modeling of near-field natural analogues and the extent to which present models can predict conditions in geothermal fields.

  1. High-level nuclear waste borosilicate glass: A compendium of characteristics

    SciTech Connect

    Cunnane, J.C.; Bates, J.K.; Ebert, W.L.; Feng, X.; Mazer, J.J.; Wronkiewicz, D.J.; Sproull, J.; Bourcier, W.L.; McGrail, B.P.

    1992-12-01

    With the imminent startup, in the United States, of facilities for vitrification of high-level nuclear waste, a document has been prepared that compiles the scientific basis for understanding the alteration of the waste glass products under the range of service conditions to which they may be exposed during storage, transportation, and eventual geologic disposal. A summary of selected parts of the content of this document is provided. Waste glass alterations in a geologic repository may include corrosion of the glass network due to groundwater and/or water vapor contact. Experimental testing results are described and interpreted in terms of the underlying chemical reactions and physical processes involved. The status of mechanistic modeling, which can be used for long-term predictions, is described and the remaining uncertainties associated with long-term simulations are summarized.

  2. High-level nuclear waste borosilicate glass: A compendium of characteristics

    SciTech Connect

    Cunnane, J.C.; Bates, J.K.; Ebert, W.L.; Feng, X.; Mazer, J.J.; Wronkiewicz, D.J. ); Sproull, J. ); Bourcier, W.L. ); McGrail, B.P. )

    1992-01-01

    With the imminent startup, in the United States, of facilities for vitrification of high-level nuclear waste, a document has been prepared that compiles the scientific basis for understanding the alteration of the waste glass products under the range of service conditions to which they may be exposed during storage, transportation, and eventual geologic disposal. A summary of selected parts of the content of this document is provided. Waste glass alterations in a geologic repository may include corrosion of the glass network due to groundwater and/or water vapor contact. Experimental testing results are described and interpreted in terms of the underlying chemical reactions and physical processes involved. The status of mechanistic modeling, which can be used for long-term predictions, is described and the remaining uncertainties associated with long-term simulations are summarized.

  3. Tectonic characterization of a potential high-level nuclear waste repository at Yucca Mountain, Nevada

    USGS Publications Warehouse

    Whitney, John W.; O'Leary, Dennis W.

    1993-01-01

    Tectonic characterization of a potential high-level nuclear waste repository at Yucca Mountain, Nevada, is needed to assess seismic and possible volcanic hazards that could affect the site during the preclosure (next 100 years) and the behavior of the hydrologic system during the postclosure (the following 10,000 years) periods. Tectonic characterization is based on assembling mapped geological structures in their chronological order of development and activity, and interpreting their dynamic interrelationships. Addition of mechanistic models and kinematic explanations for the identified tectonic processes provides one or more tectonic models having predictive power. Proper evaluation and application of tectonic models can aid in seismic design and help anticipate probable occurrence of future geologic events of significance to the repository and its design.

  4. Characterization of high-level nuclear waste glass using magnetic measurements

    SciTech Connect

    Senftle, F.E.; Thorpe, A.N.; Grant, J.R.; Barkatt, A.

    1994-12-31

    Magnetic measurements constitute a promising method for the characterization of nuclear waste glasses in view of their simplicity and small sample weight requirements. Initial studies of simulated high-level waste glasses show that the Curie constant is generally a useful indicator of the Fe{sup 2+}:Fe{sup 3+} ratio. Glasses produced by air-cooling in large vessels show systematic deviations between experimental and calcined values, which are indicative of the presence of small amounts of crystalline iron-containing phases. Most of the iron in these phases becomes dissolved in the glass upon re-heating and more rapid quenching. The studies further show that upon leaching the glass in water some of the iron in the surface regions of the glass is converted to a form which has high temperature-independent magnetic susceptibility.

  5. Corrosion behavior of Alloy 690 and Alloy 693 in simulated nuclear high level waste medium

    NASA Astrophysics Data System (ADS)

    Samantaroy, Pradeep Kumar; Suresh, Girija; Paul, Ranita; Kamachi Mudali, U.; Raj, Baldev

    2011-11-01

    Nickel based alloys are candidate materials for the storage of high level waste (HLW) generated from reprocessing of spent nuclear fuel. In the present investigation Alloy 690 and Alloy 693 are assessed by potentiodynamic anodic polarization technique for their corrosion behavior in 3 M HNO 3, 3 M HNO 3 containing simulated HLW and in chloride medium. Both the alloys were found to possess good corrosion resistance in both the media at ambient condition. Microstructural examination was carried out by SEM for both the alloys after electrolytic etching. Compositional analysis of the passive film formed on the alloys in 3 M HNO 3 and 3 M HNO 3 with HLW was carried out by XPS. The surface of Alloy 690 and Alloy 693, both consists of a thin layer of oxide of Ni, Cr, and Fe under passivation in both the media. The results of investigation are presented in the paper.

  6. A conceptual subsurface facility design for a high-level nuclear waste repository at Yucca Mountain

    SciTech Connect

    McKenzie, D.G., III; Bhattacharyya, K.K.; Segrest, A.M.

    1996-09-01

    The US Department of Energy is responsible for the design, construction, operation and closure of a repository in which to permanently dispose of the nation`s high level nuclear waste. In addition to the objective of safely isolating the waste inventory, the repository must provide a safe working environment for its workforce, and protect the public. The conceptual design for this facility is currently being developed. Tunnel Boring Machine will be used to excavate 228 kilometers of tunneling to construct the facility over a 30 year period. The excavation operations will be physically separated from the waste emplacement operations, and each operation will have its own dedicated ventilation system. The facility is being designed to remain open for 150 years.

  7. Role of geophysics in identifying and characterizing sites for high-level nuclear waste repositories.

    USGS Publications Warehouse

    Wynn, J.C.; Roseboom, E.H.

    1987-01-01

    Evaluation of potential high-level nuclear waste repository sites is an area where geophysical capabilities and limitations may significantly impact a major governmental program. Since there is concern that extensive exploratory drilling might degrade most potential disposal sites, geophysical methods become crucial as the only nondestructive means to examine large volumes of rock in three dimensions. Characterization of potential sites requires geophysicists to alter their usual mode of thinking: no longer are anomalies being sought, as in mineral exploration, but rather their absence. Thus the size of features that might go undetected by a particular method take on new significance. Legal and regulatory considerations that stem from this different outlook, most notably the requirements of quality assurance (necessary for any data used in support of a repository license application), are forcing changes in the manner in which geophysicists collect and document their data. -Authors

  8. Selection criteria for container materials at the proposed Yucca Mountain high level nuclear waste repository

    SciTech Connect

    Halsey, W.G.

    1989-11-01

    A geological repository has been proposed for the permanent disposal of the nation`s high level nuclear waste at Yucca Mountain in the Nevada desert. The containers for this waste must remain intact for the unprecedented service lifetime of 1000 years. A combination of engineering, regulatory, and licensing requirements complicate the container material selection. In parallel to gathering information regarding the Yucca Mountain service environment and material performance data, a set of selection criteria have been established which compare candidate materials to the performance requirements, and allow a quantitative comparison of candidates. These criteria assign relative weighting to varied topic areas such as mechanical properties, corrosion resistance, fabricability, and cost. Considering the long service life of the waste containers, it is not surprising that the corrosion behavior of the material is a dominant factor. 7 refs.

  9. Heat transfer effects in vertically emplaced high level nuclear waste container

    SciTech Connect

    Moujaes, S.F.; Lei, Y.M.

    1994-05-01

    Modeling free convection heat transfer in an cylindrical annular enclosure is still an active area of research and an important problem to be addressed in the high level nuclear waste repository. For the vertically emplaced waste container, the air gap which is between the container shell and the rock borehole, have an important role of dissipating heat to surrounding rack. These waste containers are vertically emplaced in the borehole 300 meters below ground, and in a horizontal grid of 30 {times} 8 meters apart. The borehole will be capped after the container emplacement. The expected initial heat generated is between 3--4.74 kW per container depending on the type of waste. The goal of this study is to use a computer simulation model to find the borehole wall, air-gap and the container outer wall temperature distributions.

  10. Tectonic characterization of a potential high-level nuclear waste repository at Yucca Mountain, Nevada

    SciTech Connect

    Whitney, J.W.; O`Leary, D.W.

    1993-09-01

    Tectonic characterization of a potential high-level nuclear waste repository at Yucca Mountain, Nevada, is needed to assess seismic and possible volcanic hazards that could affect the site during the preclosure (next 100 years) and the behavior of the hydrologic system during the postclosure (the following 10,000 years) periods. Tectonic characterization is based on assembling mapped geological structures in their chronological order of development and activity, and interpreting their dynamic interrelationships. Addition of mechanistic models and kinematic explanations for the identified tectonic processes provides one or more tectonic models having predictive power. Proper evaluation and application of tectonic models can aid in seismic design and help anticipate probable occurrence of future geologic events of significance to the repository and its design.

  11. Conceptualization of a hypothetical high-level nuclear waste repository site in unsaturated, fractured tuff

    SciTech Connect

    Parsons, A.M.; Olague, N.E.; Gallegos, D.P.

    1991-01-01

    Under the sponsorship of the US Nuclear Regulatory Commission (NRC), Sandia National Laboratories (SNL) is developing a performance assessment methodology for the analysis of long-term disposal and isolation of high-level nuclear wastes (HLW) in alternative geologic media. As part of this exercise, SNL created a conceptualization of ground-water flow and radionuclide transport in the far field of a hypothetical HLW repository site located in unsaturated, fractured tuff formations. This study provides a foundation for the development of conceptual mathematical, and numerical models to be used in this performance assessment methodology. This conceptualization is site specific in terms of geometry, the regional ground-water flow system, stratigraphy, and structure in that these are based on information from Yucca Mountain located on the Nevada Test Site. However, in terms of processes in unsaturated, fractured, porous media, the model is generic. This report also provides a review and evaluation of previously proposed conceptual models of unsaturated and saturated flow and solute transport. This report provides a qualitative description of a hypothetical HLW repository site in fractured tuff. However, evaluation of the current knowledge of flow and transport at Yucca Mountain does not yield a single conceptual model. Instead, multiple conceptual models are possible given the existing information.

  12. Anticipated Degradation Modes of Metallic Engineered Barriers for High-Level Nuclear Waste Repositories

    NASA Astrophysics Data System (ADS)

    Rodríguez, Martín A.

    2014-03-01

    Metallic engineered barriers must provide a period of absolute containment to high-level radioactive waste in geological repositories. Candidate materials include copper alloys, carbon steels, stainless steels, nickel alloys, and titanium alloys. The national programs of nuclear waste management have to identify and assess the anticipated degradation modes of the selected materials in the corresponding repository environment, which evolves in time. Commonly assessed degradation modes include general corrosion, localized corrosion, stress-corrosion cracking, hydrogen-assisted cracking, and microbiologically influenced corrosion. Laboratory testing and modeling in metallurgical and environmental conditions of similar and higher aggressiveness than those expected in service conditions are used to evaluate the corrosion resistance of the materials. This review focuses on the anticipated degradation modes of the selected or reference materials as corrosion-resistant barriers in nuclear repositories. These degradation modes depend not only on the selected alloy but also on the near-field environment. The evolution of the near-field environment varies for saturated and unsaturated repositories considering backfilled and unbackfilled conditions. In saturated repositories, localized corrosion and stress-corrosion cracking may occur in the initial aerobic stage, while general corrosion and hydrogen-assisted cracking are the main degradation modes in the anaerobic stage. Unsaturated repositories would provide an oxidizing environment during the entire repository lifetime. Microbiologically influenced corrosion may be avoided or minimized by selecting an appropriate backfill material. Radiation effects are negligible provided that a thick-walled container or an inner shielding container is used.

  13. Waste package performance evaluations for the proposed high-level nuclear waste repository at Yucca Mountain.

    PubMed

    Mon, Kevin G; Bullard, Bryan E; Mehta, Sunil; Lee, Joon H

    2004-04-01

    The evaluation studies of the proposed repository for long-term storage of spent nuclear fuel and high-level nuclear waste at Yucca Mountain, Nevada, are underway. Fulfillment of the requirements for limiting dose to the public, which includes containment of the radioactive waste emplaced in the proposed repository and subsequent slow release of radionuclides from the Engineered Barrier System (EBS) into the geosphere, will rely on a robust waste container design, among other EBS components. Part of the evaluation process involves sensitivity studies aimed at elucidating which model parameters contribute most to the waste package and overlying drip shield degradation characteristics. The model parameters identified for this study include (1) general corrosion rate parameters and (2) stress corrosion cracking (SCC) parameters. Temperature dependence and parameter uncertainty are evaluated for the general corrosion rate model parameters while for the SCC model parameters, uncertainty treatment of stress intensity factor, crack initiation threshold, and manufacturing flaw orientations are evaluated. Based on these evaluations new uncertainty distributions are generated and recommended for future analyses. Also, early waste package failures due to improper heat treatment were added to the waste package degradation model. The results of these investigations indicate that the waste package failure profiles are governed by the manufacturing flaw orientation model parameters. PMID:15078313

  14. Yucca Mountain and High-Level Nuclear Waste Disposal: Contributions of Mineralogy to Policy

    NASA Astrophysics Data System (ADS)

    Macfarlane, A.

    2006-05-01

    High-level nuclear waste from the nuclear power industry and the nuclear weapons complex requires a geologic repository for disposal. The United States has identified a site at Yucca Mountain, Nevada for this purpose. Site selection and characterization have relied on input from earth scientists, including information about waste form behavior in a repository environment. The question of waste forms is central to the issue of reducing uncertainties in predicting the performance of a geologic repository over thousands to hundreds of thousands of years, the periods covered by standards that govern the release of radioactivity into the environment. The repository characterized by the U.S. Department of Energy at Yucca Mountain will be located in the unsaturated zone and will consequently provide an oxidizing environment for the waste emplaced there. The geochemical environment will have a large impact on the behavior of the waste, the majority of which will be spent nuclear fuel from nuclear power plants. Spent fuel is largely composed of UO2, in addition to a small fraction of fission products and actinides. Studies of natural analogues have shown that UO2 is not stable in an oxidizing environment in the presence of water and will alter to other phases. The ability of these alteration phases to contain radioactivity is still a subject of analysis. Other countries have addressed the issue of waste form stability by selecting a reducing environment in a location below the water table for their repositories. Such a choice increases the durability of spent fuel by orders of magnitude and thus reduces the uncertainties associated with predicting the performance of the repository. In the United States, the emphasis has turned away from the selection of appropriate natural barriers to transport of radioactivity and towards improvement of engineered barriers. This shift reflects a decision to abandon the natural barriers in favor of engineered ones, resulting in the

  15. REGIONAL BINNING FOR CONTINUED STORAGE OF SPENT NUCLEAR FUEL AND HIGH-LEVEL WASTES

    SciTech Connect

    W. Lee Poe, Jr

    1998-10-01

    In the Continued Storage Analysis Report (CSAR) (Reference 1), DOE decided to analyze the environmental consequences of continuing to store the commercial spent nuclear fuel (SNF) at 72 commercial nuclear power sites and DOE-owned spent nuclear fuel and high-level waste at five Department of Energy sites by region rather than by individual site. This analysis assumes that three commercial facilities pairs--Salem and Hope Creek, Fitzpatrick and Nine-Mile Point, and Dresden and Moms--share common storage due to their proximity to each other. The five regions selected for this analysis are shown on Figure 1. Regions 1, 2, and 3 are the same as those used by the Nuclear Regulatory Commission in their regulatory oversight of commercial power reactors. NRC Region 4 was subdivided into two regions to more appropriately define the two different climates that exist in NRC Region 4. A single hypothetical site in each region was assumed to store all the SNF and HLW in that region. Such a site does not exist and has no geographic location but is a mathematical construct for analytical purposes. To ensure that the calculated results for the regional analyses reflect appropriate inventory, facility and material degradation, and radionuclide transport, the waste inventories, engineered barriers, and environmental conditions for the hypothetical sites were developed from data for each of the existing sites within the given region. Weighting criteria to account for the amount and types of SNF and HLW at each site were used in the development of the environmental data for the regional site, such that the results of the analyses for the hypothetical site were representative of the sum of the results of each actual site if they had been modeled independently. This report defines the actual site data used in development of this hypothetical site, shows how the individual site data was weighted to develop the regional site, and provides the weighted data used in the CSAR analysis. It is

  16. Corrosion Behavior of Alloy 625 in Simulated Nuclear High-Level Waste Medium

    NASA Astrophysics Data System (ADS)

    Girija, S.; Nandakumar, T.; Mudali, U. Kamachi

    2015-11-01

    The present investigation aims to study the effect of various ions present in nuclear high-level waste (HLW) (acidic) medium on the corrosion resistance of Alloy 625, with solution-annealed and sensitized microstructure. The heat-affected zones are prone to sensitization during welding of components and subsequent exposure to acidic waste during service could result in intergranular corrosion in these regions and hence it was attempted to study the corrosion behavior of the alloy under sensitized conditions. Double loop electrochemical potentiokinetic reactivation test was carried out to obtain the extent of chromium depletion. Potentiodynamic anodic polarization and electrochemical noise investigations were carried out on Alloy 625 in 3 M nitric acid and simulated nuclear HLW medium (prepared in 3 M nitric acid) at 298 K and 323 K. The study showed that the alloy possess good corrosion resistance in 3 M nitric acid and simulated HLW medium. However, a marginal decrease in the corrosion resistance occurred in simulated HLW when compared to the plain acid, as observed from an increase in passivation current density, decrease in transpassive potentials, and decrease in electrochemical noise resistance. Increase in temperature of the medium and change in microstructure from solution-annealed to sensitized state further decreased the corrosion resistance of Alloy 625. Electrochemical noise time records obtained at open circuit conditions showed a stable passive film for 22 h of immersion of the alloy in 3 M nitric acid and simulated HLW. However, the amplitude of current fluctuations was higher for the sensitized microstructure when compared to the solution-annealed microstructure.

  17. Low-temperature lithium diffusion in simulated high-level boroaluminosilicate nuclear waste glasses

    SciTech Connect

    Neeway, James J.; Kerisit, Sebastien N.; Gin, Stephane; Wang, Zhaoying; Zhu, Zihua; Ryan, Joseph V.

    2014-12-01

    Ion exchange is recognized as an integral, if underrepresented, mechanism influencing glass corrosion. However, due to the formation of various alteration layers in the presence of water, it is difficult to conclusively deconvolute the mechanisms of ion exchange from other processes occurring simultaneously during corrosion. In this work, an operationally inert non-aqueous solution was used as an alkali source material to isolate ion exchange and study the solid-state diffusion of lithium. Specifically, the experiments involved contacting glass coupons relevant to the immobilization of high-level nuclear waste, SON68 and CJ-6, which contained Li in natural isotope abundance, with a non-aqueous solution of 6LiCl dissolved in dimethyl sulfoxide at 90 °C for various time periods. The depth profiles of major elements in the glass coupons were measured using time-of-flight secondary ion mass spectrometry (ToF-SIMS). Lithium interdiffusion coefficients, DLi, were then calculated based on the measured depth profiles. The results indicate that the penetration of 6Li is rapid in both glasses with the simplified CJ-6 glass (D6Li ≈ 4.0-8.0 × 10-21 m2/s) exhibiting faster exchange than the more complex SON68 glass (DLi ≈ 2.0-4.0 × 10-21 m2/s). Additionally, sodium ions present in the glass were observed to participate in ion exchange reactions; however, different diffusion coefficients were necessary to fit the diffusion profiles of the two alkali ions. Implications of the diffusion coefficients obtained in the absence of alteration layers to the long-term performance of nuclear waste glasses in a geological repository system are also discussed.

  18. Biological ramifications of the subseabed disposal of high-level nuclear waste

    SciTech Connect

    Gomez, L.S.; Hessler, R.R.; Jackson, D.W.; Marietta, M.G.; Smith, K.L. Jr.; Talbert, D.M.; Yayanos, A.A.

    1980-05-01

    The primary goal of the US Subseabed Disposal Program (SDP) is to assess the technical and environmental feasibility of disposing of high-level nuclear waste in deep-sea sediments. The subseabed biology program is charged with assessing possible ecosystem effects of radionuclides as well as possible health effects to man from radionuclides which may be released in the deep sea and transported to the ocean surface. Current biological investigations are attempting to determine benthic community structure; benthic community metabolism; the biology of deep-sea mobile scavengers; the faunal composition of midwater nekton; rates of microbial processes; and the radiation sensitivity of deep-sea organisms. Existing models of the dispersal of radionuclides in the deep sea have not considered many of the possible biological mechanisms which may influence the movement of radionuclides. Therefore, a multi-compartment foodweb model is being developed which considers both biological and physical influences on radionuclide transport. This model will allow parametric studies to be made of the impact on the ocean environment and on man of potential releases of radionuclides.

  19. Geochemistry research planning for the underground storage of high-level nuclear waste

    SciTech Connect

    Apps, J.A.

    1983-09-01

    This report is a preliminary attempt to plan a comprehensive program of geochemistry research aimed at resolving problems connected with the underground storage of high-level nuclear waste. The problems and research needs were identified in a companion report to this one. The research needs were taken as a point of departure and developed into a series of proposed projects with estimated manpowers and durations. The scope of the proposed research is based on consideration of an underground repository as a multiple barrier system. However, the program logic and organization reflect conventional strategies for resolving technological problems. The projects were scheduled and the duration of the program, critical path projects and distribution of manpower determined for both full and minimal programs. The proposed research was then compared with ongoing research within DOE, NRC and elsewhere to identify omissions in current research. Various options were considered for altering the scope of the program, and hence its cost and effectiveness. Finally, recommendations were made for dealing with omissions and uncertainties arising from program implementation. 11 references, 6 figures, 4 tables.

  20. SUMO, System performance assessment for a high-level nuclear waste repository: Mathematical models

    SciTech Connect

    Eslinger, P.W.; Miley, T.B.; Engel, D.W.; Chamberlain, P.J. II

    1992-09-01

    Following completion of the preliminary risk assessment of the potential Yucca Mountain Site by Pacific Northwest Laboratory (PNL) in 1988, the Office of Civilian Radioactive Waste Management (OCRWM) of the US Department of Energy (DOE) requested the Performance Assessment Scientific Support (PASS) Program at PNL to develop an integrated system model and computer code that provides performance and risk assessment analysis capabilities for a potential high-level nuclear waste repository. The system model that has been developed addresses the cumulative radionuclide release criteria established by the US Environmental Protection Agency (EPA) and estimates population risks in terms of dose to humans. The system model embodied in the SUMO (System Unsaturated Model) code will also allow benchmarking of other models being developed for the Yucca Mountain Project. The system model has three natural divisions: (1) source term, (2) far-field transport, and (3) dose to humans. This document gives a detailed description of the mathematics of each of these three divisions. Each of the governing equations employed is based on modeling assumptions that are widely accepted within the scientific community.

  1. Study on the colloids generated from testing of high-level nuclear waste glasses

    SciTech Connect

    Feng, X.; Buck, E.C.; Mertz, C.; Bates, J.K.; Cunnane, J.C.; Chaiko, D.J.

    1993-03-01

    The generation of colloids in the interaction of high-level nuclear waste glasses with groundwater at 90{degrees}C has been investigated. The stability of the colloidal suspensions has been characterized with respect to salt concentration, pH time, particle size, and zeta potential. The compositions and the morphology of the colloids have also been determined with transmission electron microscopy (TEM). From ourtest results combined with earlier ones, we conclude that the waste glass may contribute to the colloid formation by increasing ion concentration in groundwater, which causes nucleation of colloids; by releasing radionuclides that adsorb onto existing groundwater colloids; and by spalling colloidal-size fragments from the surface layer of the reacted glass. The colloids are silicon-rich particles, such as smectites and uranium silicates. When the salt concentration in the solution is high the colloidal suspensions agglomerate. However, the agglomerated particles can be resuspended if the salt concentration is lowered by dilution with groundwater. The colloids agglomerate quickly after the leachate is cooled to room temperature. Most of the colloids settle out of the solution within a few days at ambient temperature. The isoelectric point is at a pH of approximately 1.0. Between pH 1 and 10.5, the colloids are negatively charged, which suggests that they will deposit readily on, positively charged surfaces. The average particle size islargest at the isoelectric point and is smallest around pH 6.

  2. Study on the colloids generated from testing of high-level nuclear waste glasses

    SciTech Connect

    Feng, X.; Buck, E.C.; Mertz, C.; Bates, J.K.; Cunnane, J.C.; Chaiko, D.J.

    1993-01-01

    The generation of colloids in the interaction of high-level nuclear waste glasses with groundwater at 90[degrees]C has been investigated. The stability of the colloidal suspensions has been characterized with respect to salt concentration, pH time, particle size, and zeta potential. The compositions and the morphology of the colloids have also been determined with transmission electron microscopy (TEM). From ourtest results combined with earlier ones, we conclude that the waste glass may contribute to the colloid formation by increasing ion concentration in groundwater, which causes nucleation of colloids; by releasing radionuclides that adsorb onto existing groundwater colloids; and by spalling colloidal-size fragments from the surface layer of the reacted glass. The colloids are silicon-rich particles, such as smectites and uranium silicates. When the salt concentration in the solution is high the colloidal suspensions agglomerate. However, the agglomerated particles can be resuspended if the salt concentration is lowered by dilution with groundwater. The colloids agglomerate quickly after the leachate is cooled to room temperature. Most of the colloids settle out of the solution within a few days at ambient temperature. The isoelectric point is at a pH of approximately 1.0. Between pH 1 and 10.5, the colloids are negatively charged, which suggests that they will deposit readily on, positively charged surfaces. The average particle size islargest at the isoelectric point and is smallest around pH 6.

  3. Oxidative Alkaline leaching of Americium from simulated high-level nuclear waste sludges

    SciTech Connect

    Reed, Wendy A.; Garnov, Alexander Yu.; Rao, Linfeng; Nash, Kenneth L.; Bond, Andrew H.

    2004-01-23

    Oxidative alkaline leaching has been proposed to pre-treat the high-level nuclear waste sludges to remove some of the problematic (e.g., Cr) and/or non-radioactive (e.g., Na, Al) constituents before vitrification. It is critical to understand the behavior of actinides, americium and plutonium in particular, in oxidative alkaline leaching. We have studied the leaching behavior of americium from four different sludge simulants (BiPO{sub 4}, BiPO{sub 4 modified}, Redox, PUREX) using potassium permanganate and potassium persulfate in alkaline solutions. Up to 60% of americium sorbed onto the simulants is leached from the sludges by alkaline persulfate and permanganate. The percentage of americium leached increases with [NaOH] (between 1.0 and 5.0 M). The initial rate of americium leaching by potassium persulfate increases in the order BiPO{sub 4} sludge < Redox sludge < PUREX sludge. The data are most consistent with oxidation of Am{sup 3+} in the sludge to either AmO{sub 2}{sup +} or AmO{sub 2}{sup 2+} in solution. Though neither of these species is expected to exhibit long-term stability in solution, the potential for mobilization of americium from sludge samples would have to be accommodated in the design of any oxidative leaching process for real sludge samples.

  4. Biological ramifications of the subseabed disposal of high-level nuclear waste

    SciTech Connect

    Gomez, L.S.; Hessler, R.R.; Jackson, D.W.; Marietta, M.G.; Smith, K.L. Jr.; Talbert, D.M.; Yayanos, A.A.

    1980-01-01

    The primary goal of the US Subseabed Disposal Program (SDP) is to assess the technical and environmental feasibility of disposing of high-level nuclear waste in deep-sea sediments. The subseabed biology program is charged with assessing possible ecosystem effects of radionuclides as well as possible health effects to man from radionuclides which may be released in the deep sea and transported to the ocean surface. Current biological investigations are attempting to determine benthic community structure; benthic community metabolism; the biology of deep-sea mobile scavengers; the faunal composition of midwater nekton; rates of microbial processes, and the radiation sensitivity of deep-sea organisms. Existing models of the dispersal of radionuclides in the deep sea have not considered many of the possible biological mechanisms which may influence the movement of radionuclides. Therefore, a multi-compartment foodweb model is being developed which considers both biological and physical influences on radionuclide transport. This model will allow parametric studies to be made of the impact on the ocean environment and on man of potential releases of radionuclides.

  5. Evaluation of stainless steel zirconium alloys as high-level nuclear waste forms

    NASA Astrophysics Data System (ADS)

    McDeavitt, S. M.; Abraham, D. P.; Park, J. Y.

    1998-09-01

    Stainless steel-zirconium (SS-Zr) alloys have been developed for the consolidation and disposal of waste stainless steel, zirconium, and noble metal fission products such as Nb, Mo, Tc, Ru, Pd, and Ag recovered from spent nuclear fuel assemblies. These remnant waste metals are left behind following electrometallurgical treatment, a molten salt-based process being demonstrated by Argonne National Laboratory. Two SS-Zr compositions have been selected as baseline waste form alloys: (a) stainless steel-15 wt% zirconium (SS-15Zr) for stainless steel-clad fuels and (b) zirconium-8 wt% stainless steel (Zr-8SS) for Zircaloy-clad fuels. Simulated waste form alloys were prepared and tested to characterize the metallurgy of SS-15Zr and Zr-8SS and to evaluate their physical properties and corrosion resistance. Both SS-15Zr and Zr-8SS have multi-phase microstructures, are mechanically strong, and have thermophysical properties comparable to other metals. They also exhibit high resistance to corrosion in simulated groundwater as determined by immersion, electrochemical, and vapor hydration tests. Taken together, the microstructure, physical property, and corrosion resistance data indicate that SS-15Zr and Zr-8SS are viable materials as high-level waste forms.

  6. Evidence for dawsonite in Hanford high-level nuclear waste tanks.

    PubMed

    Reynolds, Jacob G; Cooke, Gary A; Herting, Daniel L; Warrant, R Wade

    2012-03-30

    Gibbsite [Al(OH)(3)] and boehmite (AlOOH) have long been assumed to be the most prevalent aluminum-bearing minerals in Hanford high-level nuclear waste sludge. The present study shows that dawsonite [NaAl(OH)(2)CO(3)] is also a common aluminum-bearing phase in tanks containing high total inorganic carbon (TIC) concentrations and (relatively) low dissolved free hydroxide concentrations. Tank samples were probed for dawsonite by X-ray Diffraction (XRD), Scanning Electron Microscopy with Energy Dispersive Spectrometry (SEM-EDS) and Polarized Light Optical Microscopy. Dawsonite was conclusively identified in four of six tanks studied. In a fifth tank (AN-102), the dawsonite identification was less conclusive because it was only observed as a Na-Al bearing phase with SEM-EDS. Four of the five tank samples with dawsonite also had solid phase Na(2)CO(3) · H(2)O. The one tank without observable dawsonite (Tank C-103) had the lowest TIC content of any of the six tanks. The amount of TIC in Tank C-103 was insufficient to convert most of the aluminum to dawsonite (Al:TIC mol ratio of 20:1). The rest of the tank samples had much lower Al:TIC ratios (between 2:1 and 0.5:1) than Tank C-103. One tank (AZ-102) initially had dawsonite, but dawsonite was not observed in samples taken 15 months after NaOH was added to the tank surface. When NaOH was added to a laboratory sample of waste from Tank AZ-102, the ratio of aluminum to TIC in solution was consistent with the dissolution of dawsonite. The presence of dawsonite in these tanks is of significance because of the large amount of OH(-) consumed by dawsonite dissolution, an effect confirmed with AZ-102 samples. PMID:22326826

  7. Expected environments in high-level nuclear waste and spent fuel repositories in salt

    SciTech Connect

    Claiborne, H.C.; Rickertsen, L.D., Graham, R.F.

    1980-08-01

    The purpose of this report is to describe the expected environments associated with high-level waste (HLW) and spent fuel (SF) repositories in salt formations. These environments include the thermal, fluid, pressure, brine chemistry, and radiation fields predicted for the repository conceptual designs. In this study, it is assumed that the repository will be a room and pillar mine in a rock-salt formation, with the disposal horizon located approx. 2000 ft (610 m) below the surface of the earth. Canistered waste packages containing HLW in a solid matrix or SF elements are emplaced in vertical holes in the floor of the rooms. The emplacement holes are backfilled with crushed salt or other material and sealed at some later time. Sensitivity studies are presented to show the effect of changing the areal heat load, the canister heat load, the barrier material and thickness, ventilation of the storage room, and adding a second row to the emplacement configuration. The calculated thermal environment is used as input for brine migration calculations. The vapor and gas pressure will gradually attain the lithostatic pressure in a sealed repository. In the unlikely event that an emplacement hole will become sealed in relatively early years, the vapor space pressure was calculated for three scenarios (i.e., no hole closure - no backfill, no hole closure - backfill, and hole closure - no backfill). It was assumed that the gas in the system consisted of air and water vapor in equilibrium with brine. A computer code (REPRESS) was developed assuming that these changes occur slowly (equilibrium conditions). The brine chemical environment is outlined in terms of brine chemistry, corrosion, and compositions. The nuclear radiation environment emphasized in this report is the stored energy that can be released as a result of radiation damage or crystal dislocations within crystal lattices.

  8. Lessons from Natural Analog Studies for Geologic Disposal of High-Level Nuclear Waste (Invited)

    NASA Astrophysics Data System (ADS)

    Murphy, W. M.

    2009-12-01

    For over fifty years natural analog studies have provided lessons addressing scientific, technical, and social problems concerning geologic disposal of high-level nuclear waste. Idealized concepts for permanent disposal environments evolved from an understanding of the geological, geochemical and hydrological characteristics of analogous rocks including natural salt deposits (as advocated by the US National Academy of Sciences in 1957), ancient cratonic rocks (as investigated at Lac du Bonnet, Canada, Aspö, Sweden, and Vienne, France), and marine sedimentary rock formations (as studied at Mol, Belgium, and Bure, France). Additional multidisciplinary studies have been conducted at natural sites that bear characteristics analogous to potential repository systems, notably at natural uranium (and thorium) deposits including Poços de Caldas, Brazil, Alligator Rivers, Australia, Peña Blanca, Mexico, and Oklo, Gabon. Researchers of natural analogs for geologic disposal have addressed technical uncertainties regarding processes that have transpired over large time and space scales, which are generally inaccessible to laboratory studies. Principal questions for nuclear waste disposal include the geochemical stability and alteration rates of radionuclide bearing minerals and the mechanisms and rates of transport of radionuclides in groundwater. In their most direct applications, natural analogs studies have been devoted to testing specific models for repository performance and the experimental data that support those models. Parameters used in predictive performance assessment modeling have been compared to natural system data, including mineral solubilities, sorption coefficients, diffusion rates, and colloid transport properties. For example, the rate of uraninite oxidation and the natural paragenesis of uranium mineral alteration at Peña Blanca have been compared favorably to results of experimental studies of spent fuel alteration related to the proposed repository

  9. Supplemental Performance Analyses for the Potential High-Level Nuclear Waste Repository at Yucca Mountain

    SciTech Connect

    Sevougian, S. D.; McNeish, J. A.; Coppersmith, K.; Jenni, K. E.; Rickertsen, L. D.; Swift, P. N.; Wilson, M. L.

    2002-02-26

    The U.S. Department of Energy (DOE) is considering the possible recommendation of a site at Yucca Mountain, Nevada, for the potential development of a geologic repository for the disposal of high-level radioactive waste and spent nuclear fuel. To facilitate public review and comment, in May 2001 the DOE released the Yucca Mountain Science and Engineering Report (S&ER) (1), which presents technical information supporting the consideration of the possible site recommendation. The report summarizes the results of more than 20 years of scientific and engineering studies. Based on internal reviews of the S&ER and its key supporting references, the Total System Performance Assessment for the Site Recommendation (TSPA-SR) (2) and the Analysis Model Reports and Process Model Reports cited therein, the DOE has recently identified and performed several types of analyses to supplement the treatment of uncertainty in support of the consideration of a possible site recommendation. The results of these new analyses are summarized in the two-volume report entitled FY01 Supplemental Science and Performance Analysis (SSPA) (3,4). The information in this report is intended to supplement, not supplant, the information contained in the S&ER. The DOE recognizes that important uncertainties will always remain in any assessment of the performance of a potential repository over thousands of years (1). One part of the DOE approach to recognizing and managing these uncertainties is a commitment to continued testing and analysis and to the continued evaluation of the technical basis supporting the possible recommendation of the site, such as the analysis contained in the SSPA. The goals of the work described here are to provide insights into the implications of newly quantified uncertainties, updated science, and evaluations of lower operating temperatures on the performance of a potential Yucca Mountain repository and to increase confidence in the results of the TSPA described in the S

  10. Comprehensive data base of high-level nuclear waste glasses: September 1987 status report: Volume 2, Additional appendices

    SciTech Connect

    Kindle, C.H.; Kreiter, M.R.

    1987-12-01

    The Materials Characterization Center (MCC) is assembling a comprehensive data base (CDB) of experimental data collected for high-level nuclear waste package components. The status of the CDB is summarized in Volume I of this report. Volume II contains appendices that present data from the data base and an evaluation of glass durability models applied to the data base.

  11. 10 CFR 73.51 - Requirements for the physical protection of stored spent nuclear fuel and high-level radioactive...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 2 2011-01-01 2011-01-01 false Requirements for the physical protection of stored spent... (CONTINUED) PHYSICAL PROTECTION OF PLANTS AND MATERIALS Physical Protection Requirements at Fixed Sites § 73.51 Requirements for the physical protection of stored spent nuclear fuel and high-level...

  12. 10 CFR 73.51 - Requirements for the physical protection of stored spent nuclear fuel and high-level radioactive...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 2 2012-01-01 2012-01-01 false Requirements for the physical protection of stored spent... (CONTINUED) PHYSICAL PROTECTION OF PLANTS AND MATERIALS Physical Protection Requirements at Fixed Sites § 73.51 Requirements for the physical protection of stored spent nuclear fuel and high-level...

  13. 10 CFR 73.51 - Requirements for the physical protection of stored spent nuclear fuel and high-level radioactive...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Requirements for the physical protection of stored spent... (CONTINUED) PHYSICAL PROTECTION OF PLANTS AND MATERIALS Physical Protection Requirements at Fixed Sites § 73.51 Requirements for the physical protection of stored spent nuclear fuel and high-level...

  14. 10 CFR 73.51 - Requirements for the physical protection of stored spent nuclear fuel and high-level radioactive...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 2 2014-01-01 2014-01-01 false Requirements for the physical protection of stored spent... (CONTINUED) PHYSICAL PROTECTION OF PLANTS AND MATERIALS Physical Protection Requirements at Fixed Sites § 73.51 Requirements for the physical protection of stored spent nuclear fuel and high-level...

  15. 10 CFR 73.51 - Requirements for the physical protection of stored spent nuclear fuel and high-level radioactive...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 2 2013-01-01 2013-01-01 false Requirements for the physical protection of stored spent... (CONTINUED) PHYSICAL PROTECTION OF PLANTS AND MATERIALS Physical Protection Requirements at Fixed Sites § 73.51 Requirements for the physical protection of stored spent nuclear fuel and high-level...

  16. High levels of homocysteine downregulate apolipoprotein E expression via nuclear factor kappa B

    PubMed Central

    Trusca, Violeta G; Mihai, Adina D; Fuior, Elena V; Fenyo, Ioana M; Gafencu, Anca V

    2016-01-01

    AIM: To investigate the effect of high homocysteine (Hcy) levels on apolipoprotein E (apoE) expression and the signaling pathways involved in this gene regulation. METHODS: Reverse transcriptase polymerase chain reaction (RT-PCR) and Western blot were used to assess apoE expression in cells treated with various concentrations (50-500 μmol/L) of Hcy. Calcium phosphate-transient transfections were performed in HEK-293 and RAW 264.7 cells to evaluate the effect of Hcy on apoE regulatory elements [promoter and distal multienhancer 2 (ME2)]. To this aim, plasmids containing the proximal apoE promoter [(-500/+73)apoE construct] alone or in the presence of ME2 [ME2/(-500/+73)apoE construct] to drive the expression of the reporter luciferase gene were used. Co-transfection experiments were carried out to investigate the downstream effectors of Hcy-mediated regulation of apoE promoter by using specific inhibitors or a dominant negative form of IKβ. In other co-transfections, the luciferase reporter was under the control of synthetic promoters containing multiple specific binding sites for nuclear factor kappa B (NF-κB), activator protein-1 (AP-1) or nuclear factor of activated T cells (NFAT). Chromatin immunoprecipitation (ChIP) assay was accomplished to detect the binding of NF-κB p65 subunit to the apoE promoter in HEK-293 treated with 500 μmol/L Hcy. As control, cells were incubated with similar concentration of cysteine. NF-κB p65 proteins bound to DNA were immunoprecipitated with anti-p65 antibodies and DNA was identified by PCR using primers amplifying the region -100/+4 of the apoE gene. RESULTS: RT-PCR revealed that high levels of Hcy (250-750 μmol/L) induced a 2-3 fold decrease in apoE mRNA levels in HEK-293 cells, while apoE gene expression was not significantly affected by treatment with lower concentrations of Hcy (100 μmol/L). Immunoblotting data provided additional evidence for the negative role of Hcy in apoE expression. Hcy decreased apoE promoter

  17. MECHANISMS AND KINETICS OF ORGANIC AGING IN HIGH-LEVEL NUCLEAR WASTES

    EPA Science Inventory

    Highly radioactive wastes stored at Hanford and Savannah River DOE sites have unresolved questions relating to safety of the stored waste, as well as needs for safe, effective, and efficient waste processing to minimize the volume of high-level waste (HLW) streams for disposal. ...

  18. Importance of transparency and traceability in building a safety case for high-level nuclear waste repositories.

    PubMed

    Mohanty, Sitakanta; Sagar, Budhi

    2002-02-01

    The complexity of the safety case for a high-level nuclear waste repository makes it imperative that deliberate and significant effort be made to incorporate in it a high level of transparency and traceability. Diverse audiences, from interested members of the public to highly trained subject matter experts, make this task difficult. A systematic study of the meaning of transparency and traceability and the implementation of the associated principles in preparing the safety case is, therefore, required. In this article, we review the existing knowledge and propose topics for further investigation. PMID:12017364

  19. Report on interim storage of spent nuclear fuel. Midwestern high-level radioactive waste transportation project

    SciTech Connect

    Not Available

    1993-04-01

    The report on interim storage of spent nuclear fuel discusses the technical, regulatory, and economic aspects of spent-fuel storage at nuclear reactors. The report is intended to provide legislators state officials and citizens in the Midwest with information on spent-fuel inventories, current and projected additional storage requirements, licensing, storage technologies, and actions taken by various utilities in the Midwest to augment their capacity to store spent nuclear fuel on site.

  20. High level of GHR nuclear translocation in skeletal muscle of a hyperplasic transgenic zebrafish.

    PubMed

    Figueiredo, Marcio A; Boyle, Robert T; Sandrini, Juliana Z; Varela, Antonio S; Marins, Luis F

    2016-01-01

    It has been reported that nuclear translocation of growth hormone receptor (GHR) may directly activate cell proliferation in mammals and birds. However, this phenomenon has not yet been described in fish. Recently, we have developed a transgenic zebrafish that overexpresses GHR in a muscle-specific manner. Considering that this transgenic model exhibits hyperplasic muscle growth, the present work aims at verifying the relationship between GHR nuclear translocation and muscle cell proliferation. This relationship was evaluated by the phosphorylation state of the proliferative MEK/ERK pathway, expression of nuclear import-related genes, immunostaining of phospho-histone H3 (PH3) as a proliferation marker, and nuclear GHR localization. The results showed a significant decrease in the phosphorylation state of ERK1/2 proteins in transgenics. Moreover, there was an increase in expression of three out of four importin genes analyzed parallel to a large flow of GHR displacement toward and into the nucleus of transgenic muscle cells. Also, transgenics presented a marked increase in PH3 staining, which indicates cell proliferation. These findings, as far as we know, are the first report suggesting a proliferative action of GHR in fish as a consequence of its increased nuclear translocation. Thus, it appears that the nuclear migration of cytokine receptors is a common event among different taxonomic groups. In addition, the results presented here highlight the possibility that these membrane proteins may be involved more directly than previously thought in the control of genes related to cell growth and proliferation. PMID:26553237

  1. Corrosion Management of the Hanford High-Level Nuclear Waste Tanks

    NASA Astrophysics Data System (ADS)

    Beavers, John A.; Sridhar, Narasi; Boomer, Kayle D.

    2014-03-01

    The Hanford site is located in southeastern Washington State and stores more than 200,000 m3 (55 million gallons) of high-level radioactive waste resulting from the production and processing of plutonium. The waste is stored in large carbon steel tanks that were constructed between 1943 and 1986. The leak and structurally integrity of the more recently constructed double-shell tanks must be maintained until the waste can be removed from the tanks and encapsulated in glass logs for final disposal in a repository. There are a number of corrosion-related threats to the waste tanks, including stress-corrosion cracking, pitting corrosion, and corrosion at the liquid-air interface and in the vapor space. This article summarizes the corrosion management program at Hanford to mitigate these threats.

  2. Managing high level nuclear waste: Social, economic, and perceived risk issues

    SciTech Connect

    Bassett, G.W. Jr.; Jenkins-Smith, H.; Silva, C.

    1995-12-01

    This summary describes a research paper concerned with social, political, and economic consequences of leaving waste at power plants. Assessments were made by surveying residents in counties where nuclear waste is stored. The intent of the research is to compare attitudes in the surveyed counties with those of Nevada residents.

  3. STUDIES RELATED TO CHEMICAL MECHANISMS OF GAS FORMATION IN HANFORD HIGH-LEVEL NUCLEAR WASTES

    EPA Science Inventory

    The research has its origin in studies at Georgia Tech into the chemical (as opposed to radiolytic) mechanisms of gas formation (H2, N2O, N2, and NH3) in nuclear waste storage tanks at Hanford, Washington, which has been supported since 1991 under DOE's comprehensive Flammable Ga...

  4. Oxidation state of multivalent elements in high-level nuclear waste glass

    SciTech Connect

    Reynolds, J.G.

    2007-07-01

    Nuclear waste contains many different elements that have more than one oxidation state. When the nuclear waste is treated by vitrification, the behavior of the element in the melter and resulting glass product depends on the stable oxidation state. The stable oxidation state in any medium can be calculated from the standard potential in that medium. Consequently, the standard potential of multi-valent elements has been measured in many silicate-melts, including ones relevant to nuclear waste treatment. In this study, the relationship between the standard potential in molten nuclear waste glass and the standard potential in water will be quantified so that the standard potential of elements that have not been measured in glass can be estimated. The regression equation was found to have an R{sup 2} statistic of 0.96 or 0.83 depending on the number of electrons transferred in the reaction. The Nernst equation was then used to calculate the oxidation state of other relevant multi-valent elements in nuclear waste glass from these standard potentials and the measured ferrous to ferric iron ratio. The calculated oxidation states were consistent with all oxidation state measurements available. The calculated oxidation states were used to rationalize the behavior of many of the multi-valent elements. For instance, chromium increases glass crystallization because it is in the trivalent-state, iodine volatilises from the melter because it is in the volatile zero-valent state, and the leaching behavior of arsenic is driven by its oxidation state. Thus, these thermodynamic calculations explain the behavior of many trace elements during the vitrification process. (authors)

  5. Rapid Transmutation of High-Level Nuclear Wastes in a Catalyzed Fusion-Driven System

    NASA Astrophysics Data System (ADS)

    Demir, Nesrin; Genç, Gamze; Altunok, Taner; Yapıcı, Hüseyin

    2009-03-01

    The aim of this study is to investigate the high-level waste (HLW) transmutation potential of fusion-driven transmuter (FDT) based on catalyzed D-D fusion plasma for various fuel fractions. The Minor actinide (MA) (237Np, 241Am, 243Am and 244Cm) and long-lived fission product (LLFP) (99Tc, 129I and 135Cs) nuclides discharged from high burn-up pressured water reactor-mixed oxide spent fuel are considered as the HLW. The volume fractions of the MA and LLFP are raised from 10 to 20% stepped by 2% and 10 to 80% stepped by 5%, respectively. The transmutation analyses have been performed for an operation period (OP) of up to 6 years by 75% plant factor ( η) under a first-wall neutron load ( P) of 5 MW/m2 by using two different computer codes, the XSDRNPM/SCALE4.4a neutron transport code and the MCNP4B Monte Carlo code. The numerical results bring out that the considered FDT has a high neutronic performance for an effective and rapid transmutation of MA and LLFP as well as the energy generation along the OP.

  6. Evaluation and testing of metering pumps for high-level nuclear waste slurries

    SciTech Connect

    Peterson, M.E.; Perez, J.M. Jr.; Blair, H.T.

    1986-06-01

    The metering pump system that delivers high-level liquid wastes (HLLW) slurry to a melter is an integral subsystem of the vitrification process. The process of selecting a pump for this application began with a technical review of pumps typically used for slurry applications. The design and operating characteristics of numerous pumps were evaluated against established criteria. Two pumps, an air-displacement slurry (ADS) pump and an air-lift pump, were selected for further development. In the development activity, from FY 1983 to FY 1985, the two pumps were subjected to long-term tests using simulated melter feed slurries to evaluate the pumps' performances. Throughout this period, the designs of both pumps were modified to better adapt them for this application. Final reference designs were developed for both the air-displacement slurry pump and the air-lift pump. Successful operation of the final reference designs has demonstrated the feasibility of both pumps. A fully remote design of the ADS pump has been developed and is currently undergoing testing at the West Valley Demonstration Project. Five designs of the ADS pump were tested and evaluated. The initial four designs proved the operating concept of the ADS pump. Weaknesses in the ADS pump system were identified and eliminated in later designs. A full-scale air-lift pump was designed and tested as a final demonstration of the air-lift pump's capabilities.

  7. Minor component study for simulated high-level nuclear waste glasses (Draft)

    SciTech Connect

    Li, H.; Langowskim, M.H.; Hrma, P.R.; Schweiger, M.J.; Vienna, J.D.; Smith, D.E.

    1996-02-01

    Hanford Site single-shell tank (SSI) and double-shell tank (DSI) wastes are planned to be separated into low activity (or low-level waste, LLW) and high activity (or high-level waste, HLW) fractions, and to be vitrified for disposal. Formulation of HLW glass must comply with glass processibility and durability requirements, including constraints on melt viscosity, electrical conductivity, liquidus temperature, tendency for phase segregation on the molten glass surface, and chemical durability of the final waste form. A wide variety of HLW compositions are expected to be vitrified. In addition these wastes will likely vary in composition from current estimates. High concentrations of certain troublesome components, such as sulfate, phosphate, and chrome, raise concerns about their potential hinderance to the waste vitrification process. For example, phosphate segregation in the cold cap (the layer of feed on top of the glass melt) in a Joule-heated melter may inhibit the melting process (Bunnell, 1988). This has been reported during a pilot-scale ceramic melter run, PSCM-19, (Perez, 1985). Molten salt segregation of either sulfate or chromate is also hazardous to the waste vitrification process. Excessive (Cr, Fe, Mn, Ni) spinel crystal formation in molten glass can also be detrimental to melter operation.

  8. Studies Related to Chemical Mechanisms of Gas Formation in Hanford High-Level Nuclear Wastes

    SciTech Connect

    E. Kent Barefield; Charles L. Liotta; Henry M. Neumann

    2002-04-08

    The objective of this work is to develop a more detailed mechanistic understanding of the thermal reactions that lead to gas production in certain high-level waste storage tanks at the Hanford, Washington site. Prediction of the combustion hazard for these wastes and engineering parameters for waste processing depend upon both a knowledge of the composition of stored wastes and the changes that they undergo as a result of thermal and radiolytic decomposition. Since 1980 when Delagard first demonstrated that gas production (H2and N2O initially, later N2 and NH3)in the affected tanks was related to oxidative degradation of metal complexants present in the waste, periodic attempts have been made to develop detailed mechanisms by which the gases were formed. These studies have resulted in the postulation of a series of reactions that account for many of the observed products, but which involve several reactions for which there is limited, or no, precedent. For example, Al(OH)4 has been postulated to function as a Lewis acid to catalyze the reaction of nitrite ion with the metal complexants, NO is proposed as an intermediate, and the ratios of gaseous products may be a result of the partitioning of NO between two or more reactions. These reactions and intermediates have been the focus of this project since its inception in 1996.

  9. An international initiative on long-term behavior of high-level nuclear waste glass

    SciTech Connect

    Gin, Stephane; Criscenti, Louise J.; Ebert, W. L.; Ferrand, Karine; Geisler, Thorsten; Harrison, Mike T.; Inagaki, Yaohiro; Mitsui, Seiichiro; Mueller, Karl T.; Marra, James C.; Pantano, Carlo G.; Pierce, Eric M.; Ryan, Joseph V.; Schofield, James M.; Steefel, Carl I.; Vienna, John D.

    2013-06-01

    Nations producing borosilicate glass as an immobilization material for radioactive wastes resulting from spent nuclear fuel reprocessing have reinforced scientific collaboration to obtain consensus on mechanisms controlling the long-term dissolution rate of glass. This goal is deemed to be crucial for the development of reliable performance assessment models for geological disposal. The collaborating laboratories all conduct fundamental and/or applied research with modern materials science techniques. The paper briefly reviews the radioactive waste vitrification programmes of the six participant nations and summarizes the state-of-the-art of glass corrosion science, emphasizing common scientific needs and justifications for on-going initiatives.

  10. Electrochemical determination of the corrosion behavior of candidate alloys proposed for containment of high level nuclear waste in tuff

    SciTech Connect

    Glass, R.S.; Overturf, G.E.; Garrison, R.E.; McCright, R.D.

    1984-06-18

    Long-term geological disposal of nuclear waste requires corrosion-resistant canister materials for encapsulation. Several austenitic stainless steels are under consideration for such purposes for the disposal of high-level waste at the candidate repository site located at Yucca Mountain, Nevada. With regard to corrosion considerations, a worst case scenario at this prospective repository location would result from the intrusion of vadose water. This preliminary study focuses on the electrochemical and corrosion behavior of the candidate canister materials under worst-case repository environments. Electrochemical parameters related to localized attack (e.g., pitting potentials) and the electrochemical corrosion rates have been examined. 15 references, 15 figures, 4 tables.

  11. Selective removal of cesium and strontium using porous frameworks from high level nuclear waste.

    PubMed

    Aguila, Briana; Banerjee, Debasis; Nie, Zimin; Shin, Yongsoon; Ma, Shengqian; Thallapally, Praveen K

    2016-05-01

    Efficient and cost-effective removal of radioactive (137)Cs and (90)Sr found in spent fuel is an important step for safe, long-term storage of nuclear waste. Solid-state materials such as resins and titanosilicate zeolites have been assessed for the removal of Cs and Sr from aqueous solutions, but there is room for improvement in terms of capacity and selectivity. Herein, we report the Cs(+) and Sr(2+) exchange potential of an ultra stable MOF, namely, MIL-101-SO3H, as a function of different contact times, concentrations, pH levels, and in the presence of competing ions. Our preliminary results suggest that MOFs with suitable ion exchange groups can be promising alternate materials for cesium and strontium removal. PMID:27055254

  12. Geotechnical modeling of high-level nuclear waste disposal by rock melting

    SciTech Connect

    Heuze, F.E.

    1981-12-01

    A new strategy has been developed for the geotechnical modeling of nuclear waste disposal by rock melting (DRM). Three seeparate tasks were performed to reach this objective: a review of the four scenarios which have been proposed for DRM, to date; an evaluation of computer-based numerical models which could be used to analyze the mechanical, thermal, and hydraulic processes involved in DRM; and a critical review of rock mass properties which are relevant to the design and safety of waste disposal by rock melting. It is concluded that several geotechnical aspects of DRM can be studied realistically with current state-of-the-art model capabilities and knowledge of material properties. The next step in the feasibility study of DRM should be a best-estimate calculation of the four cavity-melt and canister-burial concepts. These new analyses will indicate the most critical areas for subsequent research.

  13. Characterization of high level nuclear waste glass samples following extended melter idling

    SciTech Connect

    Fox, K.

    2015-06-16

    The Savannah River Site Defense Waste Processing Facility (DWPF) melter was recently idled with glass remaining in the melt pool and riser for approximately three months. This situation presented a unique opportunity to collect and analyze glass samples since outages of this duration are uncommon. The objective of this study was to obtain insight into the potential for crystal formation in the glass resulting from an extended idling period. The results will be used to support development of a crystal-tolerant approach for operation of the high level waste melter at the Hanford Tank Waste Treatment and Immobilization Plant (WTP). Two glass pour stream samples were collected from DWPF when the melter was restarted after idling for three months. The samples did not contain crystallization that was detectible by X-ray diffraction. Electron microscopy identified occasional spinel and noble metal crystals of no practical significance. Occasional platinum particles were observed by microscopy as an artifact of the sample collection method. Reduction/oxidation measurements showed that the pour stream glasses were fully oxidized, which was expected after the extended idling period. Chemical analysis of the pour stream glasses revealed slight differences in the concentrations of some oxides relative to analyses of the melter feed composition prior to the idling period. While these differences may be within the analytical error of the laboratories, the trends indicate that there may have been some amount of volatility associated with some of the glass components, and that there may have been interaction of the glass with the refractory components of the melter. These changes in composition, although small, can be attributed to the idling of the melter for an extended period. The changes in glass composition resulted in a 70-100 °C increase in the predicted spinel liquidus temperature (TL) for the pour stream glass samples relative to the analysis of the melter feed prior to

  14. Design of a mixing system for simulated high-level nuclear waste melter feed slurries

    SciTech Connect

    Peterson, M.E.; McCarthy, D.; Muhlstein, K.D.

    1986-03-01

    The Nuclear Waste Treatment Program development program consists of coordinated nonradioactive and radioactive testing combined with numerical modeling of the process to provide a complete basis for design and operation of a vitrification facility. The radioactive demonstration tests of equipment and processes are conducted before incorporation in radioactive pilot-scale melter systems for final demonstration. The mixing system evaluation described in this report was conducted as part of the nonradioactive testing. The format of this report follows the sequence in which the design of a large-scale mixing system is determined. The initial program activity was concerned with gaining an understanding of the theoretical foundation of non-Newtonian mixing systems. Section 3 of this report describes the classical rheological models that are used to describe non-Newtonian mixing systems. Since the results obtained here are only valid for the slurries utilized, Section 4, Preparation of Simulated Hanford and West Valley Slurries, describes how the slurries were prepared. The laboratory-scale viscometric and physical property information is summarized in Section 5, Laboratory Rheological Evaluations. The bench-scale mixing evaluations conducted to define the effects of the independent variables described above on the degree of mixing achieved with each slurry are described in Section 6. Bench-scale results are scaled-up to establish engineering design requirements for the full-scale mixing system in Section 7. 24 refs., 37 figs., 44 tabs.

  15. Perceived risk, stigma, and potential economic impacts of a high-level nuclear waste repository in Nevada

    SciTech Connect

    Slovic, P.; Layman, M.; Kraus, N.N.; Chalmers, J.; Gesel, G.; Flynn, J.

    1989-07-01

    This paper describes a program of research designed to assess the potential impacts of a high-level nuclear waste repository at Yucca Mountain, Nevada, upon tourism, retirement and job-related migration, and business development in Las Vegas and the state. Adverse economic impacts may be expected to result from two related social processes. One has to do with perceptions of risk and socially amplified reactions to ``unfortunate events`` associated with the repository (major and minor accidents, discoveries of radiation releases, evidence of mismanagement, attempts to sabotage or disrupt the facility, etc.). The second process that may trigger significant adverse impacts is that of stigmatization. The conceptual underpinnings of risk perception, social amplification, and stigmatization are discussed in this paper and empirical data are presented to demonstrate how nuclear images associated with Las Vegas and the State of Nevada might trigger adverse effects on tourism, migration, and business development.

  16. Studies of Corrosion Resistant Materials Being Considered for High-Level Nuclear Waste Containment in Yucca Mountain Relevant Environments

    SciTech Connect

    McCright, R.D.; Ilevbare, G.; Estill, J.; Rebak, R.

    2001-12-09

    Containment of spent nuclear fuel and vitrified forms of high level nuclear waste require use of materials that are highly corrosion resistant to all of the anticipated environmental scenarios that can occur in a geological repository. Ni-Cr-Mo Alloy 22 (UNS N60622) is proposed for the corrosion resistant outer barrier of a two-layer waste package container at the potential repository site at Yucca Mountain. A range of water compositions that may contact the outer barrier is under consideration, and a testing program is underway to characterize the forms of corrosion and to quantify the corrosion rates. Results from the testing support models for long term prediction of the performance of the container. Results obtained to date indicate a very low general corrosion rate for Alloy 22 and very high resistance to all forms of localized and environmentally assisted cracking in environments tested to date.

  17. Dedicated-site, interim storage of high-level nuclear waste as part of the management system

    PubMed Central

    Zen, E-an

    1980-01-01

    Dedicated-site interim storage of high-level reprocessed nuclear waste and of spent fuel rods is proposed as a long-term integral part of the systems approach of the national nuclear waste isolation program. Separation of interim sites for retrievable storage from permanent-disposal repositories should enhance ensurance of the performance of the latter; maintenance of retrievability at separate sites also has many advantages in both safety and possible use of waste as resources. Interim storage sites probably will not be needed beyond about 100 years from now, so the institutional and technical considerations involved in their choice should be much less stringent than those for the selection of permanent sites. Development of interim sites must be concurrent with unabated effort to identify and to develop permanent repositories. PMID:16592904

  18. Dedicated-site, interim storage of high-level nuclear waste as part of the management system.

    PubMed

    Zen, E A

    1980-11-01

    Dedicated-site interim storage of high-level reprocessed nuclear waste and of spent fuel rods is proposed as a long-term integral part of the systems approach of the national nuclear waste isolation program. Separation of interim sites for retrievable storage from permanent-disposal repositories should enhance ensurance of the performance of the latter; maintenance of retrievability at separate sites also has many advantages in both safety and possible use of waste as resources. Interim storage sites probably will not be needed beyond about 100 years from now, so the institutional and technical considerations involved in their choice should be much less stringent than those for the selection of permanent sites. Development of interim sites must be concurrent with unabated effort to identify and to develop permanent repositories. PMID:16592904

  19. Glass Property Models, Constraints, and Formulation Approaches for Vitrification of High-Level Nuclear Wastes at the US Hanford Site

    SciTech Connect

    Kim, Dong-Sang

    2015-03-02

    The legacy nuclear wastes stored in underground tanks at the US Department of Energy’s Hanford site is planned to be separated into high-level waste and low-activity waste fractions and vitrified separately. Formulating optimized glass compositions that maximize the waste loading in glass is critical for successful and economical treatment and immobilization of nuclear wastes. Glass property-composition models have been developed and applied to formulate glass compositions for various objectives for the past several decades. The property models with associated uncertainties and combined with composition and property constraints have been used to develop preliminary glass formulation algorithms designed for vitrification process control and waste form qualification at the planned waste vitrification plant. This paper provides an overview of current status of glass property-composition models, constraints applicable to Hanford waste vitrification, and glass formulation approaches that have been developed for vitrification of hazardous and highly radioactive wastes stored at the Hanford site.

  20. Direct conversion of surplus fissile materials, spent nuclear fuel, and other materials to high-level-waste glass

    SciTech Connect

    Forsberg, C.W.; Elam, K.R.

    1995-01-31

    With the end of the cold war the United States, Russia, and other countries have excess plutonium and other materials from the reductions in inventories of nuclear weapons. The United States Academy of Sciences (NAS) has recommended that these surplus fissile materials (SFMs) be processed so they are no more accessible than plutonium in spent nuclear fuel (SNF). This spent fuel standard, if adopted worldwide, would prevent rapid recovery of SFMs for the manufacture of nuclear weapons. The NAS recommended investigation of three sets of options for disposition of SFMs while meeting the spent fuel standard: (1) incorporate SFMs with highly radioactive materials and dispose of as waste, (2) partly burn the SFMs in reactors with conversion of the SFMs to SNF for disposal, and (3) dispose of the SFMs in deep boreholes. The US Government is investigating these options for SFM disposition. A new method for the disposition of SFMs is described herein: the simultaneous conversion of SFMs, SNF, and other highly radioactive materials into high-level-waste (HLW) glass. The SFMs include plutonium, neptinium, americium, and {sup 233}U. The primary SFM is plutonium. The preferred SNF is degraded SNF, which may require processing before it can be accepted by a geological repository for disposal.

  1. Effects of long-term exposure of tuffs to high-level nuclear waste-repository conditions. Preliminary report

    SciTech Connect

    Blacic, J.; Carter, J.; Halleck, P.; Johnson, P.; Shankland, T.; Andersen, R.; Spicochi, K.; Heller, A.

    1982-02-01

    Tests have been performed to explore the effects of extended exposure of tuffs from the southwestern portion of the Nevada Test Site to temperatures and pressures similar to those that will be encountered in a high-level nuclear waste repository. Tuff samples ranging from highly welded, nonzeolitized to unwelded, highly zeolitized varieties were subjected to temperatures of 80, 120, and 180{sup 0}C; confining pressures of 9.7 and 19.7 MPa; and water-pore pressures of 0.5 to 19.7 MPa for durations of 2 to 6 months. The following basic properties were measured before and after exposure and compared: tensile strength, uniaxial compressive strength, grain density, porosity, mineralogy, permeability, thermal expansion, and thermal conductivity. Depending on rock type and exposure conditions, significant changes in ambient tensile strength, compressive strength, grain density, and porosity were measured. Mineralogic examination, permeability, and thermal property measurements remain to be completed.

  2. Workshop on the role of natural analogs in geologic disposal of high-level nuclear waste: Proceedings

    SciTech Connect

    Kovach, L.A.; Murphy, W.M.

    1995-09-01

    A Workshop on the Role of Natural Analogs in Geologic Disposal of High-Level Nuclear Waste was held in San Antonio, Texas on July 22--25, 1991. The proceedings comprise seventeen papers submitted by participants at the workshop. A series of papers addresses the relation of natural analog studies to the regulation, performance assessment, and licensing of a geologic repository. Applications of reasoning by analogy are illustrated in papers on the role of natural analogs in studies of earthquakes, petroleum, and mineral exploration. A summary is provided of a recently completed, internationally coordinated natural analog study at Pocos de Caldas, Brazil. Papers also cover problems and applications of natural analog studies in four technical areas of nuclear waste management-. waste form and waste package, near-field processes and environment, far-field processes and environment, and volcanism and tectonics. Summaries of working group deliberations in these four technical areas provide reviews and proposals for natural analog applications. Individual papers have been cataloged separately.

  3. Long-Term Waste Package Degradation Studies at the Yucca Mountain Potential High-Level Nuclear Waste Repository

    SciTech Connect

    Mon, K. G.; Bullard, B. E.; Longsine, D. E.; Mehta, S.; Lee, J. H.; Monib, A. M.

    2002-02-26

    The Site Recommendation (SR) process for the potential repository for spent nuclear fuel (SNF) and high-level nuclear waste (HLW) at Yucca Mountain, Nevada is underway. Fulfillment of the requirements for substantially complete containment of the radioactive waste emplaced in the potential repository and subsequent slow release of radionuclides from the Engineered Barrier System (EBS) into the geosphere will rely on a robust waste container design, among other EBS components. Part of the SR process involves sensitivity studies aimed at elucidating which model parameters contribute most to the drip shield and waste package degradation characteristics. The model parameters identified included (a) general corrosion rate model parameters (temperature-dependence and uncertainty treatment), and (b) stress corrosion cracking (SCC) model parameters (uncertainty treatment of stress and stress intensity factor profiles in the Alloy 22 waste package outer barrier closure weld regions, the SCC initiation stress threshold, and the fraction of manufacturing flaws oriented favorably for through-wall penetration by SCC). These model parameters were reevaluated and new distributions were generated. Also, early waste package failures due to improper heat treatment were added to the waste package degradation model. The results of these investigations indicate that the waste package failure profiles are governed by the manufacturing flaw orientation model parameters and models used.

  4. Some Materials Degradation Issues in the U.S. High-Level Nuclear Waste Repository Study (The Yucca Mountain Project)

    SciTech Connect

    F. Hua; P. Pasupathi; N. Brown; K. Mon

    2005-09-19

    The safe disposal of radioactive waste requires that the waste be isolated from the environment until radioactive decay has reduced its toxicity to innocuous levels for plants, animals, and humans. All of the countries currently studying the options for disposing of high-level nuclear waste (HLW) have selected deep geologic formations to be the primary barrier for accomplishing this isolation. In U.S.A., the Nuclear Waste Policy Act of 1982 (as amended in 1987) designated Yucca Mountain in Nevada as the potential site to be characterized for high-level nuclear waste (HLW) disposal. Long-term containment of waste and subsequent slow release of radionuclides into the geosphere will rely on a system of natural and engineered barriers including a robust waste containment design. The waste package design consists of a highly corrosion resistant Ni-based Alloy 22 cylindrical barrier surrounding a Type 316 stainless steel inner structural vessel. The waste package is covered by a mailbox-shaped drip shield composed primarily of Ti Grade 7 with Ti Grade 24 structural support members. The U.S. Yucca Mountain Project has been studying and modeling the degradation issues of the relevant materials for some 20 years. This paper reviews the state-of-the-art understanding of the degradation processes based on the past 20 years studies on Yucca Mountain Project (YMP) materials degradation issues with focus on interaction between the in-drift environmental conditions and long-term materials degradation of waste packages and drip shields within the repository system during the 10,000 years regulatory period. This paper provides an overview of the current understanding of the likely degradation behavior of the waste package and drip shield in the repository after the permanent closure of the facility. The degradation scenario discussed in this paper include aging and phase instability, dry oxidation, general and localized corrosion, stress corrosion cracking and hydrogen induced

  5. Geological repository for nuclear high level waste in France from feasibility to design within a legal framework

    SciTech Connect

    Voizard, Patrice; Mayer, Stefan; Ouzounian, Gerald

    2007-07-01

    Over the past 15 years, the French program on deep geologic disposal of high level and long-lived radioactive waste has benefited from a clear legal framework as the result of the December 30, 1991 French Waste Act. To fulfil its obligations stipulated in this law, ANDRA has submitted the 'Dossier 2005 Argile' (clay) and 'Dossier 2005 Granite' to the French Government. The first of those reports presents a concept for the underground disposal of nuclear waste at a specific clay site and focuses on a feasibility study. Knowledge of the host rock characteristics is based on the investigations carried out at the Meuse/Haute Marne Underground Research Laboratory. The repository concept addresses various issues, the most important of which relates to the large amount of waste, the clay host rock and the reversibility requirement. This phase has ended upon review and evaluation of the 'Dossier 2005' made by different organisations including the National Review Board, the National Safety Authority and the NEA International Review Team. By passing the 'new', June 28, 2006 Planning Act on the sustainable management of radioactive materials and waste, the French parliament has further defined a clear legal framework for future work. This June 28 Planning Act thus sets a schedule and defines the objectives for the next phase of repository design in requesting the submission of a construction authorization application by 2015. The law calls for the repository program to be in a position to commission disposal installations by 2025. (authors)

  6. Methodologies for predicting the performance of Ni-Cr-Mo alloys proposed for high level nuclear waste containers

    SciTech Connect

    Dunn, D.S.; Cragnolino, G.A.; Sridhar, N.

    1999-07-01

    For the geologic disposal of the high level nuclear waste (HLW), aqueous corrosion is considered to be the most important factor in the long-term performance of containers, which are the main components of the engineered barrier subsystem. Container life, in turn, is important to the overall performance of the repository system. The proposed container designs and materials have evolved to include multiple barriers and highly corrosion resistant Ni-Cr-Mo alloys, such as Alloys 625 and C-22. Calculations of container life require knowledge of the initiation time and growth rate of localized corrosion. In the absence of localized corrosion, the rate of general or uniform dissolution, given by the passive current density of these materials, is needed. The onset of localized corrosion may be predicted by using the repassivation and corrosion potentials of the candidate container materials in the range of expected repository environments. In initial corrosion tests, chloride was identified as the most detrimental anionic species to the performance of Ni-Cr-Mo alloys. Repassivation potential measurements for Alloys 825, 625, and C-22, conducted over a wide range of chloride concentrations and temperatures, are reported. In addition, steady state passive current density, which will determine the container lifetime in the absence of localized corrosion, was measured for Alloy C-22 under various environmental conditions.

  7. Closure development for high-level nuclear waste containers for the tuff repository; Phase 1, Final report

    SciTech Connect

    Robitz, E.S. Jr.; McAninch, M.D. Jr.; Edmonds, D.P. |

    1990-09-01

    This report summarizes Phase 1 activities for closure development of the high-level nuclear waste package task for the tuff repository. Work was conducted under U.S. Department of Energy (DOE) Contract 9172105, administered through the Lawrence Livermore National Laboratory (LLNL), as part of the Yucca Mountain Project (YMP), funded through the DOE Office of Civilian Radioactive Waste Management (OCRWM). The goal of this phase was to select five closure processes for further evaluation in later phases of the program. A decision tree methodology was utilized to perform an objective evaluation of 15 potential closure processes. Information was gathered via a literature survey, industrial contacts, and discussions with project team members, other experts in the field, and the LLNL waste package task staff. The five processes selected were friction welding, electron beam welding, laser beam welding, gas tungsten arc welding, and plasma arc welding. These are felt to represent the best combination of weldment material properties and process performance in a remote, radioactive environment. Conceptual designs have been generated for these processes to illustrate how they would be implemented in practice. Homopolar resistance welding was included in the Phase 1 analysis, and developments in this process will be monitored via literature in Phases 2 and 3. Work was conducted in accordance with the YMP Quality Assurance Program. 223 refs., 20 figs., 9 tabs.

  8. Transportation of Spent Nuclear Fuel and High Level Waste to Yucca Mountain: The Next Step in Nevada

    SciTech Connect

    Sweeney, Robin L,; Lechel, David J.

    2003-02-25

    In the U.S. Department of Energy's ''Final Environmental Impact Statement for a Geologic Repository for the Disposal of Spent Nuclear Fuel and High-Level Radioactive Waste at Yucca Mountain, Nye County, Nevada,'' the Department states that certain broad transportation-related decisions can be made. These include the choice of a mode of transportation nationally (mostly legal-weight truck or mostly rail) and in Nevada (mostly rail, mostly legal-weight truck, or mostly heavy-haul truck with use of an associated intermodal transfer station), as well as the choice among alternative rail corridors or heavy-haul truck routes with use of an associated intermodal transfer station in Nevada. Although a rail line does not service the Yucca Mountain site, the Department has identified mostly rail as its preferred mode of transportation, both nationally and in the State of Nevada. If mostly rail is selected for Nevada, the Department would then identify a preference for one of the rail corridors in consultation with affected stakeholders, particularly the State of Nevada. DOE would then select the rail corridor and initiate a process to select a specific rail alignment within the corridor for the construction of a rail line. Five proposed rail corridors were analyzed in the Final Environmental Impact Statement. The assessment considered the impacts of constructing a branch rail line in the five 400-meter (0.25mile) wide corridors. Each corridor connects the Yucca Mountain site with an existing mainline railroad in Nevada.

  9. Examining Supply Chain Resilience for the Intermodal Shipment of Spent Nuclear Fuel and High Level Radioactive Materials

    SciTech Connect

    Peterson, Steven K

    2016-01-01

    The U.S. Department of Energy (DOE) has a significant programmatic interest in the safe and secure routing and transportation of Spent Nuclear Fuel (SNF) and High Level Waste (HLW) in the United States, including shipments entering the country from locations outside U.S borders. In any shipment of SNF/HLW, there are multiple chains; a jurisdictional chain as the material moves between jurisdictions (state, federal, tribal, administrative), a physical supply chain (which mode), as well as a custody chain (which stakeholder is in charge/possession) of the materials being transported. Given these interconnected networks, there lies vulnerabilities, whether in lack of communication between interested stakeholders or physical vulnerabilities such as interdiction. By identifying key links and nodes as well as administrative weaknesses, decisions can be made to harden the physical network and improve communication between stakeholders. This paper examines the parallel chains of oversight and custody as well as the chain of stakeholder interests for the shipments of SNF/HLW and the potential impacts on systemic resiliency. Using the Crystal River shutdown location as well as a hypothetical international shipment brought into the United States, this paper illustrates the parallel chains and maps them out visually.

  10. Dissolution Kinetics of Alumina Calcine

    SciTech Connect

    Batcheller, Thomas Aquinas

    2001-09-01

    Dissolution kinetics of alumina type non-radioactive calcine was investigated as part of ongoing research that addresses permanent disposal of Idaho High Level Waste (HLW). Calcine waste was produced from the processing of nuclear fuel at the Idaho Nuclear Technology and Engineering Center (INTEC). Acidic radioactive raffinates were solidified at ~500°C in a fluidized bed reactor to form the dry granular calcine material. Several Waste Management alternatives for the calcine are presented in the Idaho High Level Waste Draft EIS. The Separations Alternative addresses the processing of the calcine so that the HLW is ready for removal to a national geological repository by the year 2035. Calcine dissolution is the key front-end unit operation for the separations alternative.

  11. Thermal and stress analysis of hot isostatically pressed, alumina ceramic, nuclear waste containers

    SciTech Connect

    Chang, Yun; Hoenig, C.L.

    1990-03-01

    The Yucca Mountain Project is studying design and fabrication options for a safe durable container in which to store nuclear waste underground at Yucca Mountain, Nevada. The ceramic container discussed here is an alternative to using a metal container. This ceramic alternative would be selected if site conditions prove too corrosive to use metals for nuclear waste storage. Some of the engineering problems addressed in this study were: the stress generated in the alumina container by compressive loads when 4000 to 40,000 psi of external pressure is applied; the thermal stress in the container during the heating and cooling processes; the temperature histories of the container in various production scenarios and the power required for typical heaters; the fastest possible turnaround time to heat, seal, and cool the container commensurate with preserving the structural integrity of the ceramic and the closure; the testing of some commercial heating elements to determine the maximum available heat output; and the trade-offs between the minimization in thermal stress and cycle time for closure. 2 refs., 23 figs., 2 tabs.

  12. An analysis of the back end of the nuclear fuel cycle with emphasis on high-level waste management, volume 1

    NASA Technical Reports Server (NTRS)

    1977-01-01

    The programs and plans of the U.S. government for the "back end of the nuclear fuel cycle" were examined to determine if there were any significant technological or regulatory gaps and inconsistencies. Particular emphasis was placed on analysis of high-level nuclear waste management plans, since the permanent disposal of radioactive waste has emerged as a major factor in the public acceptance of nuclear power. The implications of various light water reactor fuel cycle options were examined including throwaway, stowaway, uranium recycle, and plutonium plus uranium recycle. The results of this study indicate that the U.S. program for high-level waste management has significant gaps and inconsistencies. Areas of greatest concern include: the adequacy of the scientific data base for geological disposal; programs for the the disposal of spent fuel rods; interagency coordination; and uncertainties in NRC regulatory requirements for disposal of both commercial and military high-level waste.

  13. Chemical decomposition of high-level nuclear waste storage/disposal glasses under irradiation. 1997 annual progress report

    SciTech Connect

    Griscom, D.L.; Merzbacher, C.I.

    1997-01-01

    'The objective of this research is to use the sensitive technique of electron spin resonance (ESR) to look for evidence of radiation-induced chemical decomposition of vitreous forms contemplated for immobilization of plutonium and/or high-level nuclear wastes, to interpret this evidence in terms of existing knowledge of glass structure, and to recommend certain materials for further study by other techniques, particularly electron microscopy and measurements of gas evolution by high-vacuum mass spectroscopy. Previous ESR studies had demonstrated that an effect of y rays on a simple binary potassium silicate glass was to induce superoxide (O{sub 2}{sup -}) and ozonide (O{sub 3}{sup -}) as relatively stable product of long-term irradiation Accordingly, some of the first experiments performed as a part of the present effort involved repeating this work. A glass of composition 44 K{sub 2}O: 56 SiO{sub 2} was prepared from reagent grade K{sub 2}CO3 and SiO{sub 2} powders melted in a Pt crucible in air at 1,200 C for 1.5 hr. A sample irradiated to a dose of 1 MGy (1 MGy = 10{sup 8} rad) indeed yielded the same ESR results as before. To test the notion that the complex oxygen ions detected may be harbingers of radiation-induced phase separation or bubble formation, a small-angle neutron scattering (SANS) experiment was performed. SANS is theoretically capable of detecting voids or bubbles as small as 10 \\305 in diameter. A preliminary experiment was carried out with the collaboration of Dr. John Barker (NIST). The SANS spectra for the irradiated and unirradiated samples were indistiguishable. A relatively high incoherent background (probably due to the presence of protons) may obscure scattering from small gas bubbles and therefore decrease the effective resolution of this technique. No further SANS experiments are planned at this time.'

  14. The strategy of the Belgian nuclear research centre in the area of high-level waste form compatibility research

    SciTech Connect

    Lemmens, Karel; Cachoir, Christelle; Valcke, Elie; Ferrand, Karine; Aertsens, Marc; Mennecart, Thierry

    2007-07-01

    The Belgian Nuclear Research Centre (SCK.CEN) has a long-standing expertise in research concerning the compatibility of waste forms with the final disposal environment. For high level waste, most attention goes to two waste forms that are relevant for Belgium, namely (1) vitrified waste from the reprocessing of spent fuel, and (2) spent fuel as such, referring to the direct disposal scenario. The expertise lies especially in the study of the chemical interactions between the waste forms and the disposal environment. This is done by laboratory experiments, supported by modeling. The experiments vary from traditional leach tests, to more specific tests for the determination of particular parameters, and highly realistic experiments. This results in a description of the phenomena that are expected upon disposal of the waste forms, and in quantitative data that allow a conservative long-term prediction of the in situ life time of the waste form. The predictions are validated by in situ experiments in the underground research laboratory HADES. The final objective of these studies, is to estimate the contribution of the waste form to the overall safety of the disposal system, as part of the Safety and Feasibility Case, planned by the national agency ONDRAF/NIRAS. The recent change of the Belgian disposal concept from an engineered barrier system based on the use of bentonite clay to a system based on a concrete buffer has caused a reorientation of the research programme. The expertise in the area of clay-waste interaction will however be maintained, to develop experimental methodologies in collaboration with other countries, and as a potential support to the decision making in those countries where a clay based near field is still the reference. The paper explains the current R and D approach, and highlights some recent experimental set-ups available at SCK.CEN for this purpose, with some illustrating results. (authors)

  15. Geomicrobiology of High-Level Nuclear Waste-Contaminated Vadose Sediments at the Hanford Site, Washington State

    PubMed Central

    Fredrickson, James K.; Zachara, John M.; Balkwill, David L.; Kennedy, David; Li, Shu-mei W.; Kostandarithes, Heather M.; Daly, Michael J.; Romine, Margaret F.; Brockman, Fred J.

    2004-01-01

    Sediments from a high-level nuclear waste plume were collected as part of investigations to evaluate the potential fate and migration of contaminants in the subsurface. The plume originated from a leak that occurred in 1962 from a waste tank consisting of high concentrations of alkali, nitrate, aluminate, Cr(VI), 137Cs, and 99Tc. Investigations were initiated to determine the distribution of viable microorganisms in the vadose sediment samples, probe the phylogeny of cultivated and uncultivated members, and evaluate the ability of the cultivated organisms to survive acute doses of ionizing radiation. The populations of viable aerobic heterotrophic bacteria were generally low, from below detection to ∼104 CFU g−1, but viable microorganisms were recovered from 11 of 16 samples, including several of the most radioactive ones (e.g., >10 μCi of 137Cs/g). The isolates from the contaminated sediments and clone libraries from sediment DNA extracts were dominated by members related to known gram-positive bacteria. Gram-positive bacteria most closely related to Arthrobacter species were the most common isolates among all samples, but other phyla high in G+C content were also represented, including Rhodococcus and Nocardia. Two isolates from the second-most radioactive sample (>20 μCi of 137Cs g−1) were closely related to Deinococcus radiodurans and were able to survive acute doses of ionizing radiation approaching 20 kGy. Many of the gram-positive isolates were resistant to lower levels of gamma radiation. These results demonstrate that gram-positive bacteria, predominantly from phyla high in G+C content, are indigenous to Hanford vadose sediments and that some are effective at surviving the extreme physical and chemical stress associated with radioactive waste. PMID:15240306

  16. Factors Limiting Microbial Growth and Activity at a Proposed High-Level Nuclear Repository, Yucca Mountain, Nevada

    PubMed Central

    Kieft, T. L.; Kovacik, W. P.; Ringelberg, D. B.; White, D. C.; Haldeman, D. L.; Amy, P. S.; Hersman, L. E.

    1997-01-01

    As part of the characterization of Yucca Mountain, Nev., as a potential repository for high-level nuclear waste, volcanic tuff was analyzed for microbial abundance and activity. Tuff was collected aseptically from nine sites along a tunnel in Yucca Mountain. Microbial abundance was generally low: direct microscopic cell counts were near detection limits at all sites (3.2 x 10(sup4) to 2.0 x 10(sup5) cells g(sup-1) [dry weight]); plate counts of aerobic heterotrophs ranged from 1.0 x 10(sup1) to 3.2 x 10(sup3) CFU g(sup-1) (dry weight). Phospholipid fatty acid concentrations (0.1 to 3.7 pmol g(sup-1)) also indicated low microbial biomasses; diglyceride fatty acid concentrations, indicative of dead cells, were in a similar range (0.2 to 2.3 pmol g(sup-1)). Potential microbial activity was quantified as (sup14)CO(inf2) production in microcosms containing radiolabeled substrates (glucose, acetate, and glutamic acid); amendments with water and nutrient solutions (N and P) were used to test factors potentially limiting this activity. Similarly, the potential for microbial growth and the factors limiting growth were determined by performing plate counts before and after incubating volcanic tuff samples for 24 h under various conditions: ambient moisture, water-amended, and amended with various nutrient solutions (N, P, and organic C). A high potential for microbial activity was demonstrated by high rates of substrate mineralization (as much as 70% of added organic C in 3 weeks). Water was the major limiting factor to growth and microbial activity, while amendments with N and P resulted in little further stimulation. Organic C amendments stimulated growth more than water alone. PMID:16535670

  17. Chemical decomposition of high-level nuclear waste storage/disposal glasses under irradiation. 1998 annual progress report

    SciTech Connect

    Griscom, D.L.; Merzbacher, C.I.

    1998-06-01

    'The objective of this project is to employ the technique of electron spin resonance (ESR), in conjunction with other experimental methods, to study radiation-induced decomposition of vitreous compositions proposed for immobilization/disposal of high-level nuclear wastes (HLW) or excess weapons plutonium. ESR is capable of identifying, even at the parts-per-million level, displaced atoms, ruptured bonds, and free radicals created by radiation in such glassy forms. For example, one of the scientific goals is to determine whether ESR-detectable superoxide (O{sub 2}{sup -}) and ozonide (O{sub 3}{sup -}) ions are precursors of radiation-induced oxygen gas bubbles reported by other investigators. The fundamental understandings obtained in this study will enable reliable predictions of the long-term effects of and decays of the immobilized radionuclides on HLW glasses. This report represents the results of an 18-month effort performed under a 3-year research award. Four categories of materials were studied: (1) several actual and proposed HLW glass compositions fabricated at Savannah River Technology Center (SRTC), samples of which had been irradiated to a dose of 30 MGy (1 Gy = 100 rad) to simulate decay effects, (2) several high-iron phosphate glasses fabricated at the University of Missouri-Rolla (UMR), (3) one other model HLW glass and several simulated natural glasses which had been implanted with 160-keV He{sup +} ions to simulate-decay damage, and (4) an actual geological glass damaged by decays of trace amounts of contained {sup 238}U and {sup 232}Th over a period of 65 Myears. Among the category-1 materials were two samples of Defense Waste Processing Facility (DWPF) borosilicate glasses modeling compositions currently being used to vitrify HLW at SRTC. The ESR spectra recorded for the unirradiated DWPF-glass simulants were attributable to Fe 3{sup +} ions. The 30-MGy irradiation was found to change the Fe{sup 3+} concentration of these glasses by a

  18. Comprehensive data base of high-level nuclear waste glasses: September 1987 status report: Volume 1, Discussion and glass durability data

    SciTech Connect

    Kindle, C.H.; Kreiter, M.R.

    1987-12-01

    The Materials Characterization Center (MCC) at Pacific Northwest Laboratory is assembling a comprehensive data base (CDB) of experimental data collected for high-level nuclear waste package components. Data collected throughout the world are included in the data base; current emphasis is on waste glasses and their properties. The goal is to provide a data base of properties and compositions and an analysis of dominant property trends as a function of composition. This data base is a resource that nuclear waste producers, disposers, and regulators can use to compare properties of a particular high-level nuclear waste glass product with the properties of other glasses of similar compositions. Researchers may use the data base to guide experimental tests to fill gaps in the available knowledge or to refine empirical models. The data are incorporated into a computerized data base that will allow the data to be extracted based on, for example, glass composition or test duration. 3 figs.

  19. Foreign programs for the storage of spent nuclear power plant fuels, high-level waste canisters and transuranic wastes

    SciTech Connect

    Harmon, K.M.; Johnson, A.B. Jr.

    1984-04-01

    The various national programs for developing and applying technology for the interim storage of spent fuel, high-level radioactive waste, and TRU wastes are summarized. Primary emphasis of the report is on dry storage techniques for uranium dioxide fuels, but data are also provided concerning pool storage.

  20. High Level Requirements for the Nuclear Energy -- Knowledge Base for Advanced Modeling and Simulation (NE-KAMS)

    SciTech Connect

    Rich Johnson; Hyung Lee; Kimberlyn C. Mousseau

    2011-09-01

    The US Department of Energy, Office of Nuclear Energy (DOE-NE), has been tasked with the important mission of ensuring that nuclear energy remains a compelling and viable energy source in the U.S. The motivations behind this mission include cost-effectively meeting the expected increases in the power needs of the country, reducing carbon emissions and reducing dependence on foreign energy sources. In the near term, to ensure that nuclear power remains a key element of U.S. energy strategy and portfolio, the DOE-NE will be working with the nuclear industry to support safe and efficient operations of existing nuclear power plants. In the long term, to meet the increasing energy needs of the U.S., the DOE-NE will be investing in research and development (R&D) and working in concert with the nuclear industry to build and deploy new, safer and more efficient nuclear power plants. The safe and efficient operations of existing nuclear power plants and designing, licensing and deploying new reactor designs, however, will require focused R&D programs as well as the extensive use and leveraging of advanced modeling and simulation (M&S). M&S will play a key role in ensuring safe and efficient operations of existing and new nuclear reactors. The DOE-NE has been actively developing and promoting the use of advanced M&S in reactor design and analysis through its R&D programs, e.g., the Nuclear Energy Advanced Modeling and Simulation (NEAMS) and Consortium for Advanced Simulation of Light Water Reactors (CASL) programs. Also, nuclear reactor vendors are already using CFD and CSM, for design, analysis, and licensing. However, these M&S tools cannot be used with confidence for nuclear reactor applications unless accompanied and supported by verification and validation (V&V) and uncertainty quantification (UQ) processes and procedures which provide quantitative measures of uncertainty for specific applications. The Nuclear Energy Knowledge base for Advanced Modeling and Simulation

  1. Performance assessment of the direct disposal in unsaturated tuff or spent nuclear fuel and high-level waste owned by USDOE: Volume 2, Methodology and results

    SciTech Connect

    Rechard, R.P.

    1995-03-01

    This assessment studied the performance of high-level radioactive waste and spent nuclear fuel in a hypothetical repository in unsaturated tuff. The results of this 10-month study are intended to help guide the Office of Environment Management of the US Department of Energy (DOE) on how to prepare its wastes for eventual permanent disposal. The waste forms comprised spent fuel and high-level waste currently stored at the Idaho National Engineering Laboratory (INEL) and the Hanford reservations. About 700 metric tons heavy metal (MTHM) of the waste under study is stored at INEL, including graphite spent nuclear fuel, highly enriched uranium spent fuel, low enriched uranium spent fuel, and calcined high-level waste. About 2100 MTHM of weapons production fuel, currently stored on the Hanford reservation, was also included. The behavior of the waste was analyzed by waste form and also as a group of waste forms in the hypothetical tuff repository. When the waste forms were studied together, the repository was assumed also to contain about 9200 MTHM high-level waste in borosilicate glass from three DOE sites. The addition of the borosilicate glass, which has already been proposed as a final waste form, brought the total to about 12,000 MTHM.

  2. Factors influencing the performance of carbon steel overpacks in the proposed high-level nuclear waste repository

    SciTech Connect

    Cragnolino, G.A.; Dunn, D.S.; Angell, P.; Pan, Y.M.; Sridhar, N.

    1998-12-31

    A C-Mn steel, ASTM A516 Grade 55, is the primary candidate material for the outer metallic barrier in the current advanced conceptual design for the waste package in the proposed high-level radioactive waste repository at Yucca Mountain. The expected performance of this steel and that of the alternate material, A387 Grade 22 (2 1/4Cr-1Mo) steel, as affected by thermal embrittlement, dry or humid air oxidation, uniform and localized aqueous corrosion, microbially influenced corrosion, and stress corrosion cracking, is discussed on the basis of experimental studies and a review of information and data available in the literature.

  3. Preliminary total-system analysis of a potential high-level nuclear waste repository at Yucca Mountain

    SciTech Connect

    Eslinger, P.W.; Doremus, L.A.; Engel, D.W.; Miley, T.B.; Murphy, M.T.; Nichols, W.E.; White, M.D.; Langford, D.W.; Ouderkirk, S.J.

    1993-01-01

    The placement of high-level radioactive wastes in mined repositories deep underground is considered a disposal method that would effectively isolate these wastes from the environment for long periods of time. This report describes modeling performed at PNL for Yucca Mountain between May and November 1991 addressing the performance of the entire repository system related to regulatory criteria established by the EPA in 40 CFR Part 191. The geologic stratigraphy and material properties used in this study were chosen in cooperation with performance assessment modelers at Sandia National Laboratories (SNL). Sandia modeled a similar problem using different computer codes and a different modeling philosophy. Pacific Northwest Laboratory performed a few model runs with very complex models, and SNL performed many runs with much simpler (abstracted) models.

  4. IR and Raman Spectroscopy of Sodium-Aluminophosphate Glasses for Immobilizing High-Level Wastes from Spent Nuclear Fuel Reprocessing

    NASA Astrophysics Data System (ADS)

    Stefanovsky, S. V.; Myasoedov, B. F.; Remizov, M. B.; Belanova, E. A.

    2014-09-01

    The structure of sodium-aluminophosphate glasses containing constituents of high-level wastes (cesium, magnesium, copper, and molybdenum oxides) from uranium-graphite reactors was studied by IR and Raman spectroscopy coupled with x-ray diffraction. The structural network was shown to be composed of short P-O chains with embedded AlO4 tetrahedra. Cross-linking by Mg2+ was possible in the Mg-bearing samples. The effect of the other oxides (Cs2O, MoO3, CuO) on the glass structure was negligible for the occurring amounts. The glasses devitrified partially upon quenching and more strongly upon annealing. This was reflected in splitting of the vibrational bands for bonds in the glass anionic structural motif.

  5. Initial performance assessment of the disposal of spent nuclear fuel and high-level waste stored at Idaho National Engineering Laboratory. Volume 2: Appendices

    SciTech Connect

    Rechard, R.P.

    1993-12-01

    This performance assessment characterized plausible treatment options conceived by the Idaho National Engineering Laboratory (INEL) for its spent fuel and high-level radioactive waste and then modeled the performance of the resulting waste forms in two hypothetical, deep, geologic repositories: one in bedded salt and the other in granite. The results of the performance assessment are intended to help guide INEL in its study of how to prepare wastes and spent fuel for eventual permanent disposal. This assessment was part of the Waste Management Technology Development Program designed to help the US Department of Energy develop and demonstrate the capability to dispose of its nuclear waste, as mandated by the Nuclear Waste Policy Act of 1982. The waste forms comprised about 700 metric tons of initial heavy metal (or equivalent units) stored at the INEL: graphite spent fuel, experimental low enriched and highly enriched spent fuel, and high-level waste generated during reprocessing of some spent fuel. Five different waste treatment options were studied; in the analysis, the options and resulting waste forms were analyzed separately and in combination as five waste disposal groups. When the waste forms were studied in combination, the repository was assumed to also contain vitrified high-level waste from three DOE sites for a common basis of comparison and to simulate the impact of the INEL waste forms on a moderate-sized repository, The performance of the waste form was assessed within the context of a whole disposal system, using the U.S. Environmental Protection Agency`s Environmental Radiation Protection Standards for Management and Disposal of Spent Nuclear Fuel, High-Level and Transuranic Radioactive Wastes, 40 CFR 191, promulgated in 1985. Though the waste form behavior depended upon the repository type, all current and proposed waste forms provided acceptable behavior in the salt and granite repositories.

  6. DOCUMENTATION OF NATIONAL WEATHER CONDITIONS AFFECTING LONG-TERM DEGRADATION OF COMMERCIAL SPENT NUCLEAR FUEL AND DOE SPENT NUCLEAR FUEL AND HIGH-LEVEL WASTE

    SciTech Connect

    W. L. Poe, Jr.; P.F. Wise

    1998-11-01

    The U.S. Department of Energy (DOE) is preparing a proposal to construct, operate 2nd monitor, and eventually close a repository at Yucca Mountain in Nye County, Nevada, for the geologic disposal of spent nuclear fuel (SNF) and high-level radioactive waste (HLW). As part of this effort, DOE has prepared a viability assessment and an assessment of potential consequences that may exist if the repository is not constructed. The assessment of potential consequences if the repository is not constructed assumes that all SNF and HLW would be left at the generator sites. These include 72 commercial generator sites (three commercial facility pairs--Salem and Hope Creek, Fitzpatrick and Nine Mile Point, and Dresden and Morris--would share common storage due to their close proximity to each other) and five DOE sites across the country. DOE analyzed the environmental consequences of the effects of the continued storage of these materials at these sites in a report titled Continued Storage Analysis Report (CSAR; Reference 1 ) . The CSAR analysis includes a discussion of the degradation of these materials when exposed to the environment. This document describes the environmental parameters that influence the degradation analyzed in the CSAR. These include temperature, relative humidity, precipitation chemistry (pH and chemical composition), annual precipitation rates, annual number of rain-days, and annual freeze/thaw cycles. The document also tabulates weather conditions for each storage site, evaluates the degradation of concrete storage modules and vaults in different regions of the country, and provides a thermal analysis of commercial SNF in storage.

  7. High level nuclear waste glass corrosion in synthetic clay pore solution and retention of actinides in secondary phases

    NASA Astrophysics Data System (ADS)

    Bosbach, D.; Luckscheiter, B.; Brendebach, B.; Denecke, M. A.; Finck, N.

    2009-03-01

    The corrosion of the simulated high level waste glass GP WAK1 in synthetic clay pore solution was studied in batch-type experiments at 323 and 363 K with special focus on the effect of high carbonate concentration in solution. The corrosion rate after 130 days was <10-4g m-2 d-1 - no significant effect of the carbonate was identified. During glass corrosion, crystalline secondary phases (powellite, barite, calcite, anhydrite and clay-like Mg(Ca,Fe)-silicates) were formed. To obtain a molecular level picture of radionuclide speciation within the alteration layer, spectroscopic methods have been applied including grazing incidence X-ray absorption spectroscopy (XAS) to study the structural changes in the coordination of uranyl upon alteration layer formation. The number of equatorial oxygen atoms increases from 4 in the bulk glass to 5 in the alteration layer. Furthermore, reduced coordination symmetry was found. Hectorite, a frequently observed secondary clay mineral within the glass alteration layer, was synthesized in the presence of trivalent f-elements (e.g. Eu) and structurally characterized using time-resolved laser fluorescence spectroscopy. Structural incorporation into the octahedral layer is indicated.

  8. Application of single ion activity coefficients to determine solvent extraction mechanism for components of high level nuclear waste

    SciTech Connect

    Nunez, L.; Vandegrift, G.F.

    1995-12-31

    The TRUEX solvent extraction process is being developed to remove and concentrate transuranic (TRU) elements from high-level and TRU radioactive wastes currently stored at US Department of Energy sites. Phosphoric acid is one of the chemical species of concern at the Hanford site where bismuth phosphate was used to recover plutonium. The mechanism of phosphoric acid extraction with TRUEX-NPH solvent at 25{degrees}C was determined by phosphoric acid distribution ratios, which were measured by using phosphoric acid radiotracer and a variety of aqueous phases containing different concentrations of nitric acid and nitrate ions. A model was developed for predicting phosphoric acid distribution ratios as a function of the thermodynamic activities of nitrate ion and hydrogen ion. The Generic TRUEX Model (GTM) was used to calculate these activities based on the Bromley method. The derived model supports CMPO and TBP extraction of a phosphoric acid-nitric acid complex and a CMPO-phosphoric acid complex in TRUEX-NPH solvent.

  9. Development of an Integrated Raman and Turbidity Fiber Optic Sensor for the In-Situ Analysis of High Level Nuclear Waste - 13532

    SciTech Connect

    Gasbarro, Christina; Bello, Job; Bryan, Samuel; Lines, Amanda; Levitskaia, Tatiana

    2013-07-01

    Stored nuclear waste must be retrieved from storage, treated, separated into low- and high-level waste streams, and finally put into a disposal form that effectively encapsulates the waste and isolates it from the environment for a long period of time. Before waste retrieval can be done, waste composition needs to be characterized so that proper safety precautions can be implemented during the retrieval process. In addition, there is a need for active monitoring of the dynamic chemistry of the waste during storage since the waste composition can become highly corrosive. This work describes the development of a novel, integrated fiber optic Raman and light scattering probe for in situ use in nuclear waste solutions. The dual Raman and turbidity sensor provides simultaneous chemical identification of nuclear waste as well as information concerning the suspended particles in the waste using a common laser excitation source. (authors)

  10. Development of an Integrated Raman and Turbidity Fiber Optic Sensor for the In-Situ Analysis of High Level Nuclear Waste

    SciTech Connect

    Gasbarro, Christina; Bello, Job M.; Bryan, Samuel A.; Lines, Amanda M.; Levitskaia, Tatiana G.

    2013-02-24

    Stored nuclear waste must be retrieved from storage, treated, separated into low- and high-level waste streams, and finally put into a disposal form that effectively encapsulates the waste and isolates it from the environment for a long period of time. Before waste retrieval can be done, waste composition needs to be characterized so that proper safety precautions can be implemented during the retrieval process. In addition, there is a need for active monitoring of the dynamic chemistry of the waste during storage since the waste composition can become highly corrosive. This work describes the development of a novel, integrated fiber optic Raman and light scattering probe for in situ use in nuclear waste solutions. The dual Raman and turbidity sensor provides simultaneous chemical identification of nuclear waste as well as information concerning the suspended particles in the waste using a common laser excitation source.

  11. Perceived risk, stigma, and potential economic impacts of a high-level nuclear waste repository in Nevada

    SciTech Connect

    Slovic, P.; Layman, M.; Kraus, N.; Flynn, J.; Chalmers, J.; Gesell, G.

    1991-12-01

    This study investigates the potential impacts of the proposed nuclear waste repository at Yucca Mountain, Nevada, upon tourism, retirement and job-related migration, and business development in Las Vegas and the state. Adverse impacts may be expected to result from perceptions of risk, stigmatization, and socially amplified reactions to `unfortunate events` associated with the repository (major and minor accidents, discoveries of radiation releases, evidence of mismanagement, attempts to sabotage or disrupt the facility, etc.). The conceptual underpinnings of risk perception, stigmatization, and social amplification are discussed and empirical data are presented to demonstrate how nuclear images associated with Las Vegas and the State of Nevada might trigger adverse economic effects. The possibility that intense negative imagery associated with the repository may cause significant harm to Nevada`s economy can no longer be ignored by serious attempts to assess the risks and impacts of this unique facility. The behavioral processes described here appear relevant as well to the social impact assessment of any proposed facility that produces, uses, transports, or disposes of hazardous materials.

  12. A report on high-level nuclear waste transportation: Prepared pursuant to assembly concurrent resolution No. 8 of the 1987 Nevada Legislature

    SciTech Connect

    1988-12-01

    This report has been prepared by the staff of the State of Nevada Agency for Nuclear Projects/Nuclear Waste Project Office (NWPO) in response to Assembly Concurrent Resolution No. 8 (ACR 8), passed by the Nevada State Legislature in 1987. ACR 8 directed the NWPO, in cooperation with affected local governments and the Legislative committee on High-Level Radioactive Waste, to prepare this report which scrutinizes the US Department of Energy`s (DOE) plans for transportation of high-level radioactive waste to the proposed yucca Mountain repository, which reviews the regulatory structure under which shipments to a repository would be made and which presents NWPO`s plans for addressing high-level radioactive waste transportation issues. The report is divided into three major sections. Section 1.0 provides a review of DOE`s statutory requirements, its repository transportation program and plans, the major policy, programmatic, technical and institutional issues and specific areas of concern for the State of Nevada. Section 2.0 contains a description of the current federal, state and tribal transportation regulatory environment within which nuclear waste is shipped and a discussion of regulatory issues which must be resolved in order for the State to minimize risks and adverse impacts to its citizens. Section 3.0 contains the NWPO plan for the study and management of repository-related transportation. The plan addresses four areas, including policy and program management, regulatory studies, technical reviews and studies and institutional relationships. A fourth section provides recommendations for consideration by State and local officials which would assist the State in meeting the objectives of the plan.

  13. Defense Waste Processing Facility (DWPF): The vitrification of high-level nuclear waste. (Latest citations from the NTIS bibliographic database). Published Search

    SciTech Connect

    1997-06-01

    The bibliography contains citations concerning a production-scale facility and the world`s largest plant for the vitrification of high-level radioactive nuclear wastes (HLW) located in the United States. Initially based on the selection of borosilicate glass as the reference waste form, the citations present the history of the development including R&D projects and the actual construction of the production facility at the DOE Savannah River Plant (SRP). (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  14. Selection of candidate container materials for the conceptual waste package design for a potential high level nuclear waste repository at Yucca Mountain

    SciTech Connect

    Van Konynenburg, R.A.; Halsey, W.G.; McCright, R.D.; Clarke, W.L. Jr.; Gdowski, G.E.

    1993-02-01

    Preliminary selection criteria have been developed, peer-reviewed, and applied to a field of 41 candidate materials to choose three alloys for further consideration during the advanced conceptual design phase of waste package development for a potential high level nuclear waste repository at Yucca Mountain, Nevada. These three alloys are titanium grade 12, Alloy C-4, and Alloy 825. These selections are specific to the particular conceptual design outlined in the Site Characterization Plan. Other design concepts that may be considered in the advanced conceptual design phase may favor other materials choices.

  15. Final Environmental Impact Statement for a Geologic Repository for the Disposal of Spent Nuclear Fuel and High-Level Radioactive Waste at Yucca Mountain, Nye County, Nevada

    SciTech Connect

    N /A

    2002-10-25

    The purpose of this environmental impact statement (EIS) is to provide information on potential environmental impacts that could result from a Proposed Action to construct, operate and monitor, and eventually close a geologic repository for the disposal of spent nuclear fuel and high-level radioactive waste at the Yucca Mountain site in Nye County, Nevada. The EIS also provides information on potential environmental impacts from an alternative referred to as the No-Action Alternative, under which there would be no development of a geologic repository at Yucca Mountain.

  16. Perceived risk, stigma, and potential economic impacts of a high-level nuclear waste repository in Nevada

    SciTech Connect

    Slovic, P.

    1989-12-31

    This paper addresses the potential for the proposed Yucca Mountain repository to have serious adverse economic impacts on the city of Las Vegas and the State of Nevada. Adverse economic impacts may be expected to result from two related social processes. One has to do with perceptions of risk and socially amplified reactions to unfortunate events associated with the repository (major and minor accidents, discoveries of radiation releases, evidence of mismanagement, attempts to sabotage or disrupt the facility, etc.). The second process that may trigger significant adverse impacts is that of stigmatization. The conceptual underpinnings of risk perception, social amplification, and stigma are discussed in this paper and empirical data are presented to demonstrate how nuclear images associated with Las Vegas and the State of Nevada might trigger adverse effects on tourism, migration, and business development.

  17. AN EVALUATION OF HYDROGEN INDUCED CRACKING SUSCEPTIBILITY OF TITANIUM ALLOYS IN US HIGH-LEVEL NUCLEAR WASTE REPOSITORY ENVIRONMENTS

    SciTech Connect

    G. De; K. Mon; G. Gordon; D. Shoesmith; F. Hua

    2006-02-21

    This paper evaluates hydrogen-induced cracking (HIC) susceptibility of titanium alloys in environments anticipated in the Yucca Mountain nuclear waste repository with particular emphasis on the. effect of the oxide passive film on the hydrogen absorption process of titanium alloys being evaluated. The titanium alloys considered in this review include Ti 2, 5 , 7, 9, 11, 12, 16, 17, 18, 24 and 29. In general, the concentration of hydrogen in a titanium alloy can increase due to absorption of atomic hydrogen produced from passive general corrosion of that alloy or galvanic coupling of it to a less noble metal. It is concluded that under the exposure conditions anticipated in the Yucca Mountain repository, the HIC of titanium drip shield will not occur because there will not be sufficient hydrogen in the metal even after 10,000 years of emplacement. Due to the conservatisms adopted in the current evaluation, this assessment is considered very conservative.

  18. Instrumentation report 1: specification, design, calibration, and installation of instrumentation for an experimental, high-level, nuclear waste storage facility

    SciTech Connect

    Brough, W.G.; Patrick, W.C.

    1982-01-01

    The Spent Fuel Test-Climax (SFT-C) is being conducted 420 m underground at the Nevada Test Site under the auspices of the US Department of Energy. The test facility houses 11 spent fuel assemblies from an operating commercial nuclear reactor and numerous other thermal sources used to simulate the near-field effects of a large repository. We developed a large-scale instrumentation plan to ensure that a sufficient quality and quantity of data were acquired during the three- to five-year test. These data help satisfy scientific, operational, and radiation safety objectives. Over 800 data channels are being scanned to measure temperature, electrical power, radiation, air flow, dew point, stress, displacement, and equipment operation status (on/off). This document details the criteria, design, specifications, installation, calibration, and current performance of the entire instrumentation package.

  19. Numerical studies of fluid and heat flow near high-level nuclear waste packages emplaced in partially saturated fractured tuff

    SciTech Connect

    Pruess, K.; Tsang, Y.W.; Wang, J.S.Y.

    1984-11-01

    We have performed modeling studies on the simultaneous transport of heat, liquid water, vapor, and air in partially saturated fractured porous rock. Formation parameters were chosen as representative of the potential repository horizon in the Topopah Spring Unit of the Yucca Mountain tuffs. The presence of fractures makes the transport problem very complex, both in terms of flow geometry and physics. The numerical simulator "TOUGH" used for our flow calculations takes into account most of the physical effects which are important in multi-phase fluid and heat flow. It has provisions for handling the extreme non-linearities which arise in phase transitions, component disappearances, and capillary discontinuities at fracture faces. We model a region around an infinite linear string of nuclear waste canisters, taking into account both the discrete fractures and the porous matrix. From an analysis of the results obtained with explicit fractures, we develop equivalent continuum models which can reproduce the temperature, saturation, and pressure variation, and gas and liquid flow rates of the discrete fracture-porous matrix calculations. The equivalent continuum approach makes use of a generalized relative permeability concept to take into account the fracture effects. This results in a substantial simplification of the flow problem which makes larger scale modeling of complicated unsaturated fractured porous systems feasible. Potential applications for regional scale simulations and limitations of the continuum approach are discussed. 35 refs., 14 figs., 4 tabs.

  20. Fabrication development for high-level nuclear waste containers for the tuff repository; Phase 1 final report

    SciTech Connect

    Domian, H.A.; Holbrook, R.L.; LaCount, D.F. |

    1990-09-01

    This final report completes Phase 1 of an engineering study of potential manufacturing processes for the fabrication of containers for the long-term storage of nuclear waste. An extensive literature and industry review was conducted to identify and characterize various processes. A technical specification was prepared using the American Society of Mechanical Engineers Boiler & Pressure Vessel Code (ASME BPVC) to develop the requirements. A complex weighting and evaluation system was devised as a preliminary method to assess the processes. The system takes into account the likelihood and severity of each possible failure mechanism in service and the effects of various processes on the microstructural features. It is concluded that an integral, seamless lower unit of the container made by back extrusion has potential performance advantages but is also very high in cost. A welded construction offers lower cost and may be adequate for the application. Recommendations are made for the processes to be further evaluated in the next phase when mock-up trials will be conducted to address key concerns with various processes and materials before selecting a primary manufacturing process. 43 refs., 26 figs., 34 tabs.

  1. Toward a risk assessment of the spent fuel and high-level nuclear waste disposal system. Risk assessment requirements, literature review, methods evaluation: an interim report

    SciTech Connect

    Hamilton, L.D.; Hill, D.; Rowe, M.D.; Stern, E.

    1986-04-01

    This report provides background information for a risk assessment of the disposal system for spent nuclear fuel and high-level radioactive waste (HLW). It contains a literature review, a survey of the statutory requirements for risk assessment, and a preliminary evaluation of methods. The literature review outlines the state of knowledge of risk assessment and accident consequence analysis in the nuclear fuel cycle and its applicability to spent fuel and HLW disposal. The survey of statutory requirements determines the extent to which risk assessment may be needed in development of the waste-disposal system. The evaluation of methods reviews and evaluates merits and applicabilities of alternative methods for assessing risks and relates them to the problems of spent fuel and HLW disposal. 99 refs.

  2. Guidelines on the scope, content, and use of comprehensive risk assessment in the management of high-level nuclear waste transportation

    SciTech Connect

    Golding, D.; White, A.

    1990-12-01

    This report discusses the scope of risk assessment strategies in the management of the transport of high-level radioactive wastes. In spite of the shortcomings of probabilistic risk assessment(PRA), the Transportation Needs Assessment recommended this as the preferred methodology to assess the risks of high level nuclear waste (HLNW) transportation. A PRA also will need to heed the lessons learned from the development and application of PRA elsewhere, such as in the nuclear power industry. A set of guidelines will aid this endeavor by outlining the appropriate scope, content, and use of a risk assessment which is more responsive to the uncertainties, human-technical interactions, social forces, and iterative relationship with risk management strategies, than traditional PRAS. This more expansive definition, which encompasses but is not totally reliant on rigorous data requirements and quantitative probability estimates, we term Comprehensive Risk Assessment (CRA) Guidelines will be developed in three areas: the limitations of existing methodologies and suggested modifications; CRA as part of a flexible, effective, adaptive risk management system for HLNW transportation; and, the use of CRA in risk communication.

  3. Is Yucca Mountain a long-term solution for disposing of US spent nuclear fuel and high-level radioactive waste?

    PubMed

    Thorne, M C

    2012-06-01

    On 26 January 2012, the Blue Ribbon Commission on America's Nuclear Future released a report addressing, amongst other matters, options for the managing and disposal of high-level waste and spent fuel. The Blue Ribbon Commission was not chartered as a siting commission. Accordingly, it did not evaluate Yucca Mountain or any other location as a potential site for the storage or disposal of spent nuclear fuel and high-level waste. Nevertheless, if the Commission's recommendations are followed, it is clear that any future proposals to develop a repository at Yucca Mountain would require an extended period of consultation with local communities, tribes and the State of Nevada. Furthermore, there would be a need to develop generally applicable regulations for disposal of spent fuel and high-level radioactive waste, so that the Yucca Mountain site could be properly compared with alternative sites that would be expected to be identified in the initial phase of the site-selection process. Based on what is now known of the conditions existing at Yucca Mountain and the large number of safety, environmental and legal issues that have been raised in relation to the DOE Licence Application, it is suggested that it would be imprudent to include Yucca Mountain in a list of candidate sites for future evaluation in a consent-based process for site selection. Even if there were a desire at the local, tribal and state levels to act as hosts for such a repository, there would be enormous difficulties in attempting to develop an adequate post-closure safety case for such a facility, and in showing why this unsaturated environment should be preferred over other geological contexts that exist in the USA and that are more akin to those being studied and developed in other countries. PMID:22569220

  4. Walk the Line: The Development of Route Selection Standards for Spent Nuclear Fuel and High-level Radioactive Waste in the United States - 13519

    SciTech Connect

    Dilger, Fred; Halstead, Robert J.; Ballard, James D.

    2013-07-01

    Although storage facilities for spent nuclear fuel (SNF) and high-level radioactive waste (HLRW) are widely dispersed throughout the United States, these materials are also relatively concentrated in terms of geographic area. That is, the impacts of storage occur in a very small geographic space. Once shipments begin to a national repository or centralized interim storage facility, the impacts of SNF and HLRW will become more geographically distributed, more publicly visible, and almost certainly more contentious. The selection of shipping routes will likely be a major source of controversy. This paper describes the development of procedures, regulations, and standards for the selection of routes used to ship spent nuclear fuel and high-level radioactive waste in the United States. The paper begins by reviewing the circumstances around the development of HM-164 routing guidelines. The paper discusses the significance of New York City versus the Department of Transportation and application of HM-164. The paper describes the methods used to implement those regulations. The paper will also describe the current HM-164 designated routes and will provide a summary data analysis of their characteristics. This analysis will reveal the relatively small spatial scale of the effects of HM 164. The paper will then describe subsequent developments that have affected route selection for these materials. These developments include the use of 'representative routes' found in the Department of Energy (DOE) 2008 Supplemental Environmental Impact Statement for the formerly proposed Yucca Mountain geologic repository. The paper will describe recommendations related to route selection found in the National Academy of Sciences 2006 report Going the Distance, as well as recommendations found in the 2012 Final Report of the Blue Ribbon Commission on America's Nuclear Future. The paper will examine recently promulgated federal regulations (HM-232) for selection of rail routes for hazardous

  5. Atomic Description of the Interface between Silica and Alumina in Aluminosilicates through Dynamic Nuclear Polarization Surface-Enhanced NMR Spectroscopy and First-Principles Calculations

    PubMed Central

    2015-01-01

    Despite the widespread use of amorphous aluminosilicates (ASA) in various industrial catalysts, the nature of the interface between silica and alumina and the atomic structure of the catalytically active sites are still subject to debate. Here, by the use of dynamic nuclear polarization surface enhanced NMR spectroscopy (DNP SENS) and density functional theory (DFT) calculations, we show that on silica and alumina surfaces, molecular aluminum and silicon precursors are, respectively, preferentially grafted on sites that enable the formation of Al(IV) and Si(IV) interfacial sites. We also link the genesis of Brønsted acidity to the surface coverage of aluminum and silicon on silica and alumina, respectively. PMID:26244620

  6. Atomic Description of the Interface between Silica and Alumina in Aluminosilicates through Dynamic Nuclear Polarization Surface-Enhanced NMR Spectroscopy and First-Principles Calculations.

    PubMed

    Valla, Maxence; Rossini, Aaron J; Caillot, Maxime; Chizallet, Céline; Raybaud, Pascal; Digne, Mathieu; Chaumonnot, Alexandra; Lesage, Anne; Emsley, Lyndon; van Bokhoven, Jeroen A; Copéret, Christophe

    2015-08-26

    Despite the widespread use of amorphous aluminosilicates (ASA) in various industrial catalysts, the nature of the interface between silica and alumina and the atomic structure of the catalytically active sites are still subject to debate. Here, by the use of dynamic nuclear polarization surface enhanced NMR spectroscopy (DNP SENS) and density functional theory (DFT) calculations, we show that on silica and alumina surfaces, molecular aluminum and silicon precursors are, respectively, preferentially grafted on sites that enable the formation of Al(IV) and Si(IV) interfacial sites. We also link the genesis of Brønsted acidity to the surface coverage of aluminum and silicon on silica and alumina, respectively. PMID:26244620

  7. The role of natural glasses as analogues in projecting the long-term alteration of high-level nuclear waste glasses: Part 1

    SciTech Connect

    Mazer, J.J.

    1993-12-31

    The common observation of glasses persisting in natural environments for long periods of time (up to tens of millions of years) provides compelling evidence that these materials can be kinetically stable in a variety of subsurface environments. This paper reviews how natural and historical synthesized glasses can be employed as natural analogues for understanding and projecting the long-term alteration of high-level nuclear waste glasses. The corrosion of basaltic glass results in many of the same alteration features found in laboratory testing of the corrosion of high-level radioactive waste glasses. Evidence has also been found indicating similarities in the rate controlling processes, such as the effects of silica concentration on corrosion in groundwater and in laboratory leachates. Naturally altered rhyolitic glasses and tektites provide additional evidence that can be used to constrain estimates of long-term waste glass alteration. When reacted under conditions where water is plentiful, the corrosion for these glasses is dominated by network hydrolysis, while the corrosion is dominated by molecular water diffusion and secondary mineral formation under conditions where water contact is intermittent or where water is relatively scarce. Synthesized glasses that have been naturally altered result in alkali-depleted alteration features that are similar to those found for natural glasses and for nuclear waste glasses. The characteristics of these alteration features appear to be dependent on the alteration conditions which affect the dominant reaction processes during weathering. In all cases, care must be taken to ensure that the information being provided by natural analogues is related to nuclear waste glass corrosion in a clear and meaningful way.

  8. CHARACTERIZATION OF DEFENSE NUCLEAR WASTE USING HAZARDOUS WASTE GUIDANCE. APPLICATIONS TO HANFORD SITE ACCELERATED HIGH-LEVEL WASTE TREATMENT AND DISPOSAL MISSION0

    SciTech Connect

    Hamel, William; Huffman, Lori; Lerchen, Megan; Wiemers, Karyn

    2003-02-27

    Federal hazardous waste regulations were developed for management of industrial waste. These same regulations are also applicable for much of the nation's defense nuclear wastes. At the U.S. Department of Energy's (DOE) Hanford Site in southeast Washington State, one of the nation's largest inventories of nuclear waste remains in storage in large underground tanks. The waste's regulatory designation and its composition and form constrain acceptable treatment and disposal options. Obtaining detailed knowledge of the tank waste composition presents a significant portion of the many challenges in meeting the regulatory-driven treatment and disposal requirements for this waste. Key in applying the hazardous waste regulations to defense nuclear wastes is defining the appropriate and achievable quality for waste feed characterization data and the supporting evidence demonstrating that applicable requirements have been met at the time of disposal. Application of a performance-based approach to demonstrating achievable quality standards will be discussed in the context of the accelerated high-level waste treatment and disposal mission at the Hanford Site.

  9. INSTALLATION OF A POST-ACCIDENT CONFINEMENT HIGH-LEVEL RADIATION MONITORING SYSTEM IN THE KOLA NUCLEAR POWER STATION (UNIT 2) IN RUSSIA

    SciTech Connect

    GREENE,G.A.; GUPPY,J.G.

    1998-09-01

    This is the final report on the INSP project entitled, ``Post-Accident Confinement High-Level Radiation Monitoring System'' conducted by BNL under the authorization of Project Work Plan WBS 1.2.2.6 (Attachment 1). This project was initiated in February 1993 to assist the Russians in reducing risks associated with the continued operation of older Soviet-designed nuclear power plants, specifically the Kola VVER-440/230 Unit 2, through improved accident detection capability, specifically by the installation of a dual train high-level radiation detection system in the confinement of Unit 2 of the Kola NPP. The major technical objective of this project was to provide, install and make operational the necessary hardware inside the confinement of the Kola NPP Unit 2 to provide early and reliable warning of the release of radionuclides from the reactor into the confinement air space as an indication of the occurrence of a severe accident at the plant. In addition, it was intended to provide hands-on experience and training to the Russian plant workers in the installation, operation, calibration and maintenance of the equipment in order that they may use the equipment without continued US assistance as an effective measure to improve reactor safety at the plant.

  10. Development of Dodecaniobate Keggin Chain Materials as Alternative Sorbents for SR and Actinide Removal from High-Level Nuclear Waste Solutions

    SciTech Connect

    Nyman, May; Bonhomme, Francois

    2004-03-28

    The current baseline sorbent (monosodium titanate) for Sr and actinide removal from Savannah River Site's high level wastes has excellent adsorption capabilities for Sr but poor performance for the actinides. We are currently investigating the development of alternative materials that sorb radionuclides based on chemical affinity and/or size selectivity. The polyoxometalates, negatively-charged metal oxo clusters, have known metal binding properties and are of interest for radionuclide sequestration. We have developed a class of Keggin-ion based materials, where the Keggin ions are linked in 1- dimensional chains separated by hydrated, charge-balancing cations. These Nb-based materials are stable in the highly basic nuclear waste solutions and show good selectivity for Sr and Pu. Synthesis, characterization and structure of these materials in their native forms and Sr-exchanged forms will be presented.

  11. FURTHER DEVELOPMENT OF MODIFIED MONOSODIUM TITANATE, AN IMPROVED SORBENT FOR PRETREATMENT OF HIGH LEVEL NUCLEAR WASTE AT THE SAVANNAH RIVER SITE

    SciTech Connect

    Taylor-Pashow, K.; Hobbs, D.; Fondeur, F.; Fink, S.

    2011-01-12

    High-level nuclear waste produced from fuel reprocessing operations at the Savannah River Site (SRS) requires pretreatment to remove Cs-137, Sr-90, and alpha-emitting radionuclides (i.e., actinides) prior to disposal onsite as low level waste. Separation processes planned at SRS include caustic side solvent extraction, for Cs-137 removal, and sorption of Sr-90 and alpha-emitting radionuclides onto monosodium titanate (MST). The predominant alpha-emitting radionuclides in the highly alkaline waste solutions include plutonium isotopes Pu-238, Pu-239, and Pu-240. This paper describes recent results from the development of an improved titanate material that exhibits increased removal kinetics and effective capacity for Sr-90 and alpha-emitting radionuclides compared to the baseline MST material.

  12. Progress in evaluation of radionuclide geochemical information developed by DOE high-level nuclear waste repository site projects. Annual report, October 1984-September 1985. Volume 4

    SciTech Connect

    Meyer, R.E.; Arnold, W.D.; Blencoe, J.G.; Jacobs, G.K.; Kelmers, A.D.; Seeley, F.G.; Whatley, S.K.

    1986-05-01

    Information pertaining to the potential geochemical behavior of radionuclides at candidate sites for a high-level radioactive waste repository, which is being developed by projects within the Department of Energy (DOE), is being evaluated by Oak Ridge National Laboratory for the Nuclear Regulatory Commission (NRC). During this report period, emphasis was placed on the evaluation of information pertinent to the Hanford site in southeastern Washington. Results on the sorption/solubility behavior of technetium, neptunium, and uranium in the basalt/water geochemical system are summarized and compared to the results of DOE. Also, summaries of results are reported from two geochemical modeling studies: (1) an evaluation of the information developed by DOE on the native copper deposits of Michigan as a natural analog for the emplacement of copper canisters in a repository in basalt, and (2) calculation of the solubility and speciation of radionuclides for representative groundwaters from the Yucca Mountain site in Nevada.

  13. Overview of calcite/opal deposits at or near the proposed high-level nuclear waste site, Yucca Mountain, Nevada, USA: Pedogenic, hypogene, or both?

    NASA Astrophysics Data System (ADS)

    Hill, C. A.; Dublyansky, Y. V.; Harmon, R. S.; Schluter, C. M.

    1995-09-01

    Calcite/opal deposits (COD) at Yucca Mountain were studied with respect to their regional and field geology, petrology and petrography, chemistry and isotopic geochemistry, and fluid inclusions. They were also compared with true pedogenic deposits (TPD), groundwater spring deposits (GSD), and calcite vein deposits (CVD) in the subsurface. Some of the data are equivocal and can support either a hypogene or pedogenic origin for these deposits. However, Sr-, C-, and O-isotope, fluid inclusion, and other data favor a hypogene interpretation. A hypothesis that may account for all currently available data is that the COD precipitated from warm, CO2-rich water that episodically upwelled along faults during the Pleistocene, and which, upon reaching the surface, flowed downslope within existing alluvial, colluvial, eluvial, or soil deposits. Being formed near, or on, the topographic surface, the COD acquired characteristics of pedogenic deposits. This subject relates to the suitability of Yucca Mountain as a high-level nuclear waste site.

  14. Axisymmetric Analysis of Multilayered Thermoelastic Media with Application to a Repository for Heat-Emitting High-Level Nuclear Waste in a Geological Formation

    NASA Astrophysics Data System (ADS)

    Yang, Yang; Datcheva, Maria; Schanz, Tom

    2016-05-01

    Comprehensive analytical solutions to 3D axisymmetric problems for static response of multilayered thermoelastic media subjected to surface loads and containing sources are presented in this study. The solution strategy employs Laplace and Hankel transforms to the field variables. The problem is formulated in cylindrical coordinate system and in this coordinate system vector surface harmonics and generalized propagator matrix are introduced to find the solution for the problem for the behaviour of thermoelastic multilayered media subject to surface loads and containing heat sources. A high-order adaptive Gaussian quadrature method with continued fraction expansions is employed to approximate the integral solutions expressed in terms of semi-infinite Hankel-type integrals. It is the first time to apply the proposed solution method to investigate the behaviour of repository for heat-emitting high-level nuclear waste (HLW) in a geological formation where the HLW can be regarded as a decaying with time point heat source.

  15. Axisymmetric analysis of multilayered thermoelastic media with application to a repository for heat-emitting high-level nuclear waste in a geological formation

    NASA Astrophysics Data System (ADS)

    Yang, Yang; Datcheva, Maria; Schanz, Tom

    2016-08-01

    Comprehensive analytical solutions to 3-D axisymmetric problems for static response of multilayered thermoelastic media subjected to surface loads and containing sources are presented in this study. The solution strategy employs Laplace and Hankel transforms to the field variables. The problem is formulated in cylindrical coordinate system and in this coordinate system vector surface harmonics and generalized propagator matrix are introduced to find the solution for the problem for the behaviour of thermoelastic multilayered media subject to surface loads and containing heat sources. A high-order adaptive Gaussian quadrature method with continued fraction expansions is employed to approximate the integral solutions expressed in terms of semi-infinite Hankel-type integrals. It is the first time to apply the proposed solution method to investigate the behaviour of repository for heat-emitting high-level nuclear waste (HLW) in a geological formation where the HLW can be regarded as a decaying with time point heat source.

  16. Impurities in rock-salt: consequences for the temperature increases at the disposal of high-level nuclear waste. [Kainite, Kieserite

    SciTech Connect

    van den Broek, W.M.G.T.

    1982-06-01

    In part A the thermal properties of halite and the other materials occurring in rock-salt (the 'impurities') are collected. Except for sylvite (the specific heat of this salt is about 70% of the value for halite) all specific heats are larger than the specific heat of halite. The consequences for the temperature increases at the disposal of high-level nuclear waste in rock-salt are discussed for impurity concentrations of 1, 5, 10 and 15%. If the presence and distribution of the impurities are not taken into account, then - under the most unfavorable conditions - extra temperature increases of about 3% per cent impurity may occur. If, however, the geological composition and its geometry for the disposal region are known, the temperature increases can be calculated more accurately: they may or may not differ from those for pure halite. In part B the measurement of the thermal conductivity for four salts (kainite, kieserite, carnallite, and polyhalite) is described.

  17. Initial performance assessment of the disposal of spent nuclear fuel and high-level waste stored at Idaho National Engineering Laboratory. Volume 1, Methodology and results

    SciTech Connect

    Rechard, R.P.

    1993-12-01

    This performance assessment characterized plausible treatment options conceived by the Idaho National Engineering Laboratory (INEL) for its spent fuel and high-level radioactive waste and then modeled the performance of the resulting waste forms in two hypothetical, deep, geologic repositories: one in bedded salt and the other in granite. The results of the performance assessment are intended to help guide INEL in its study of how to prepare wastes and spent fuel for eventual permanent disposal. This assessment was part of the Waste Management Technology Development Program designed to help the US Department of Energy develop and demonstrate the capability to dispose of its nuclear waste. Although numerous caveats must be placed on the results, the general findings were as follows: Though the waste form behavior depended upon the repository type, all current and proposed waste forms provided acceptable behavior in the salt and granite repositories.

  18. Site characterization plan conceptual design report for a high-level nuclear waste repository in salt, vertical emplacement mode: Volume 1

    SciTech Connect

    Not Available

    1987-12-01

    This Conceptual Design Report describes the conceptual design of a high-level nuclear waste repository in salt at a proposed site in Deaf Smith County, Texas. Waste receipt, processing, packing, and other surface facility operations are described. Operations in the shafts underground are described, including waste hoisting, transfer, and vertical emplacement. This report specifically addresses the vertical emplacement mode, the reference design for the repository. Waste retrieval capability is described. The report includes a description of the layout of the surface, shafts, and underground. Major equipment items are identified. The report includes plans for decommissioning and sealing of the facility. The report discusses how the repository will satisfy performance objectives. Chapters are included on basis for design, design analyses, and data requirements for completion of future design efforts. 105 figs., 52 tabs.

  19. Cultural approach to the perception of risk. Analyzing concern about siting of a high-level nuclear waste facility in Finland

    SciTech Connect

    Litmanen, T.

    1996-12-31

    The study of local residents` attitudes toward siting a high-level nuclear waste facility in Finland took place in three municipalities (Eurajoki, Kuhmo and Agnekoski), which are being considered possible host communities for the plant. The survey showed that the NIMBY phenomenon is a common reaction in two of the three municipalities, and in the third a polarization of opinions into two opposing camps is evident. The analysis of the data indicates that the opposition consist of people who have less education, less knowledge about the facility, lower incomes, and a lower occupational status. The social base of the proponents is the opposite. The persons most critical towards the possible siting can be found among women, older people, voters of the Greens, retired persons and farmers. People who welcome nuclear waste in their vicinity can be found among men, the middle-aged, voters of the Conservative Party and business owners. The study of the perception of possible negative impacts (health and safety, environmental, economic and social) showed that residents in Kuhmo and Adnekoski were more concerned about possible hazards than the residents of Eurajoki. According to the cultural approach, these findings must be contextualized. Eurajoka, which holds more favorable attitudes than Kuhmo and Agnekoski, hosts a nuclear power plant. In the two other communities the opposition is greater, because the residents are unfamiliar with nuclear technology. The thesis of the paper is that in order to understand different opinions about the facility, one must understand the cultural logic of risk perception. People evaluate the risk as individuals, but also as members of different reference groups and in the context of local, national and international circumstances.

  20. Milestones for Selection, Characterization, and Analysis of the Performance of a Repository for Spent Nuclear Fuel and High-Level Radioactive Waste at Yucca Mountain.

    SciTech Connect

    Rechard, Robert P.

    2014-02-01

    This report presents a concise history in tabular form of events leading up to site identification in 1978, site selection in 1987, subsequent characterization, and ongoing analysis through 2008 of the performance of a repository for spent nuclear fuel and high-level radioactive waste at Yucca Mountain in southern Nevada. The tabulated events generally occurred in five periods: (1) commitment to mined geologic disposal and identification of sites; (2) site selection and analysis, based on regional geologic characterization through literature and analogous data; (3) feasibility analysis demonstrating calculation procedures and importance of system components, based on rough measures of performance using surface exploration, waste process knowledge, and general laboratory experiments; (4) suitability analysis demonstrating viability of disposal system, based on environment-specific laboratory experiments, in-situ experiments, and underground disposal system characterization; and (5) compliance analysis, based on completed site-specific characterization. Because the relationship is important to understanding the evolution of the Yucca Mountain Project, the tabulation also shows the interaction between four broad categories of political bodies and government agencies/institutions: (a) technical milestones of the implementing institutions, (b) development of the regulatory requirements and related federal policy in laws and court decisions, (c) Presidential and agency directives and decisions, and (d) critiques of the Yucca Mountain Project and pertinent national and world events related to nuclear energy and radioactive waste.

  1. Climax Granite, Nevada Test Site, as a host for a rock mechanics test facility related to the geologic disposal of high level nuclear wastes

    SciTech Connect

    Heuze, F.E.

    1981-02-01

    This document discusses the potential of the Climax pluton, at the Nevada Test Site, as the host for a granite mechanics test facility related to the geologic disposal of high-level nuclear waste. The Climax granitic pluton has been the site of three nuclear weapons effects tests: Hard Hat, Tiny Tot, and Piledriver. Geologic exploration and mapping of the granite body were performed at the occasion of these tests. Currently, it is the site Spent Fuel Test (SFT-C) conducted in the vicinity of and at the same depth as that of the Piledriver drifts. Significant exploration, mapping, and rock mechanics work have been performed and continue at this Piledriver level - the 1400 (ft) level - in the context of SFT-C. Based on our technical discussions, and on the review of the significant geological and rock mechanics work already achieved in the Climax pluton, based also on the ongoing work and the existing access and support, it is concluded that the Climax site offers great opportunities for a rock mechanics test facility. It is not claimed, however, that Climax is the only possible site or the best possible site, since no case has been made for another granite test facility in the United States. 12 figures, 3 tables.

  2. Surveys for desert tortoise on the proposed site of a high-level nuclear waste repository at the Nevada Test Site

    SciTech Connect

    Collins, E.; Sauls, M.L.; O`Farrell, T.P.

    1983-12-31

    The National Waste Terminal Storage Program is a national search for suitable sites to isolate commercial spent nuclear fuel or high-level radioactive waste. The Nevada Nuclear Waste Storage Investigation (NNWSI) managed by the U.S. Department of Energy (DOE), Nevada Operations Office, was initiated to study the suitability of a portion of Yucca Mountain on the DOE`s Nevada Test Site (NTS) as a location for such a repository. EG and G was contracted to provide information concerning the ecosystems encountered on the site. A comprehensive literature survey was conducted to evaluate the status and completeness of the existing biological information for the previously undisturbed area. Site specific studies were begun in 1981 when preliminary field surveys confirmed the presence of the desert tortoise (Gopherus agassizi) within the project area FY82 studies were designed to determine the overall distribution and abundance of the tortoise within the area likely to be impacted by NNWSI activities. The Yucca Mountain area of the Nevada Test Site is situated close to the northern range limit of the desert tortoise. Prior to the 1982 surveys, the desert tortoise was reported from only nine locations on NTS. A known population had been under study in Rock Valley about 25 miles southeast of the project area. However, the distribution and population densities of tortoise in the southwest portion of NTS were virtually unknown. Results of our surveys indicate that desert tortoise can be expected, albeit in small numbers, in a wide range of Mojavean and Transitional habitats.

  3. Non-Darcian flow in low-permeability media: key issues related to geological disposal of high-level nuclear waste in shale formations

    NASA Astrophysics Data System (ADS)

    Liu, Hui-Hai

    2014-05-01

    In clay or other low-permeability media, water flow becomes non-Darcian and characterized by the non-linear relationship between water flux and hydraulic gradient. This work is devoted to addressing a number of key issues related to geological disposal of high-level nuclear waste in clay/shale formations. It is demonstrated that water flow velocity in the damaged zone (often considered as a potential preferential advection paths in a repository) surrounding the tunnel is extremely small, as a result of non-Darcian flow behavior, such that solute transport is dominated by diffusion, rather than advection. The finding is also consistent with the often-observed existence of persistent abnormal pressures in shale formations. While relative permeability is the key parameter for modeling the unsaturated flow process, without incorporating non-Darcian flow behavior, significant errors can occur in the determination of relative permeability values from traditional measurement methods. An approach for dealing with temperature impact on non-Darcian flow and a formulation to calculate non-Darcian water flux in an anisotropic medium are presented, taking into consideration that a geological repository is subject to temperature evolution in the near field as a result of heat generated by nuclear waste, and that shale formations are generally anisotropic.

  4. Reduction of High Levels of Internal Radio-Contamination by Dietary Intervention in Residents of Areas Affected by the Fukushima Daiichi Nuclear Plant Disaster: A Case Series

    PubMed Central

    Tsubokura, Masaharu; Kato, Shigeaki; Nomura, Shuhei; Gilmour, Stuart; Nihei, Masahiko; Sakuma, Yu; Oikawa, Tomoyoshi; Kanazawa, Yukio; Kami, Masahiro; Hayano, Ryugo

    2014-01-01

    Maintaining low levels of chronic internal contamination among residents in radiation-contaminated areas after a nuclear disaster is a great public health concern. However, the efficacy of reduction measures for individual internal contamination remains unknown. To reduce high levels of internal radiation exposure in a group of individuals exposed through environmental sources, we performed careful dietary intervention with identification of suspected contaminated foods, as part of mass voluntary radiation contamination screenings and counseling program in Minamisoma Municipal General Hospital and Hirata Central Hospital. From a total of 30,622 study participants, only 9 residents displayed internal cesium-137 (Cs-137) levels of more than 50 Bq/kg. The median level of internal Cs-137 contamination in these residents at the initial screening was 4,830 Bq/body (range: 2,130–15,918 Bq/body) and 69.6 Bq/kg (range: 50.7–216.3 Bq/kg). All these residents with high levels of internal contamination consumed homegrown produce without radiation inspection, and often collected mushrooms in the wild or cultivated them on bed-logs in their homes. They were advised to consume distributed food mainly and to refrain from consuming potentially contaminated foods without radiation inspection and local produces under shipment restrictions such as mushrooms, mountain vegetables, and meat of wild life. A few months after the intervention, re-examination of Cs levels revealed remarkable reduction of internal contamination in all residents. Although the levels of internal radiation exposure appear to be minimal amongst most residents in Fukushima, a subset of the population, who unknowingly consumed highly contaminated foodstuffs, experienced high levels of internal contamination. There seem to be similarities in dietary preferences amongst residents with high internal contamination levels, and intervention based on pre- and post-test counseling and dietary advice from medical care

  5. Reduction of high levels of internal radio-contamination by dietary intervention in residents of areas affected by the Fukushima Daiichi nuclear plant disaster: a case series.

    PubMed

    Tsubokura, Masaharu; Kato, Shigeaki; Nomura, Shuhei; Gilmour, Stuart; Nihei, Masahiko; Sakuma, Yu; Oikawa, Tomoyoshi; Kanazawa, Yukio; Kami, Masahiro; Hayano, Ryugo

    2014-01-01

    Maintaining low levels of chronic internal contamination among residents in radiation-contaminated areas after a nuclear disaster is a great public health concern. However, the efficacy of reduction measures for individual internal contamination remains unknown. To reduce high levels of internal radiation exposure in a group of individuals exposed through environmental sources, we performed careful dietary intervention with identification of suspected contaminated foods, as part of mass voluntary radiation contamination screenings and counseling program in Minamisoma Municipal General Hospital and Hirata Central Hospital. From a total of 30,622 study participants, only 9 residents displayed internal cesium-137 (Cs-137) levels of more than 50 Bq/kg. The median level of internal Cs-137 contamination in these residents at the initial screening was 4,830 Bq/body (range: 2,130-15,918 Bq/body) and 69.6 Bq/kg (range: 50.7-216.3 Bq/kg). All these residents with high levels of internal contamination consumed homegrown produce without radiation inspection, and often collected mushrooms in the wild or cultivated them on bed-logs in their homes. They were advised to consume distributed food mainly and to refrain from consuming potentially contaminated foods without radiation inspection and local produces under shipment restrictions such as mushrooms, mountain vegetables, and meat of wild life. A few months after the intervention, re-examination of Cs levels revealed remarkable reduction of internal contamination in all residents. Although the levels of internal radiation exposure appear to be minimal amongst most residents in Fukushima, a subset of the population, who unknowingly consumed highly contaminated foodstuffs, experienced high levels of internal contamination. There seem to be similarities in dietary preferences amongst residents with high internal contamination levels, and intervention based on pre- and post-test counseling and dietary advice from medical care

  6. Modeling of the T S D E Heater Test to Investigate Crushed Salt Reconsolidation and Rock Salt Creep for the Underground Disposal of High-Level Nuclear Waste

    NASA Astrophysics Data System (ADS)

    Blanco Martin, L.; Rutqvist, J.; Birkholzer, J. T.; Wolters, R.; Lux, K. H.

    2014-12-01

    Rock salt is a potential medium for the underground disposal of nuclear waste because it has several assets, in particular its water and gas tightness in the undisturbed state, its ability to heal induced fractures and its high thermal conductivity as compared to other shallow-crustal rocks. In addition, the run-of-mine, granular salt, may be used to backfill the mined open spaces. We present simulation results associated with coupled thermal, hydraulic and mechanical processes in the TSDE (Thermal Simulation for Drift Emplacement) experiment, conducted in the Asse salt mine in Germany [1]. During this unique test, conceived to simulate reference repository conditions for spent nuclear fuel, a significant amount of data (temperature, stress changes and displacements, among others) was measured at 20 cross-sections, distributed in two drifts in which a total of six electrical heaters were emplaced. The drifts were subsequently backfilled with crushed salt. This test has been modeled in three-dimensions, using two sequential simulators for flow (mass and heat) and geomechanics, TOUGH-FLAC and FLAC-TOUGH [2]. These simulators have recently been updated to accommodate large strains and time-dependent rheology. The numerical predictions obtained by the two simulators are compared within the framework of an international benchmark exercise, and also with experimental data. Subsequently, a re-calibration of some parameters has been performed. Modeling coupled processes in saliniferous media for nuclear waste disposal is a novel approach, and in this study it has led to the determination of some creep parameters that are very difficult to assess at the laboratory-scale because they require extremely low strain rates. Moreover, the results from the benchmark are very satisfactory and validate the capabilities of the two simulators used to study coupled thermal, mechanical and hydraulic (multi-component, multi-phase) processes relative to the underground disposal of high-level

  7. Social impacts of hazardous and nuclear facilities and events: Implications for Nevada and the Yucca Mountain high-level nuclear waste repository; [Final report

    SciTech Connect

    Freudenburg, W.R.; Carter, L.F.; Willard, W.; Lodwick, D.G.; Hardert, R.A.; Levine, A.G.; Kroll-Smith, S.; Couch, S.R.; Edelstein, M.R.

    1992-05-01

    Social impacts of a nuclear waste repository are described. Various case studies are cited such as Rocky Flats Plant, the Feed Materials Production Center, and Love Canal. The social impacts of toxic contamination, mitigating environmental stigma and loss of trust are also discussed.

  8. A Transportation Risk Assessment Tool for Analyzing the Transport of Spent Nuclear Fuel and High-Level Radioactive Waste to the Proposed Yucca Mountain Repository

    SciTech Connect

    Ralph Best; T. Winnard; S. Ross; R. Best

    2001-08-17

    The Yucca Mountain Transportation Database was developed as a data management tool for assembling and integrating data from multiple sources to compile the potential transportation impacts presented in the Draft Environmental Impact Statement for a Geologic Repository for the Disposal of Spent Nuclear Fuel and High-Level Radioactive Waste at Yucca Mountain, Nye County, Nevada (DEIS). The database uses the results from existing models and codes such as RADTRAN, RISKIND, INTERLINE, and HIGHWAY to estimate transportation-related impacts of transporting spent nuclear fuel and high-level radioactive waste from commercial reactors and U. S. Department of Energy (DOE) facilities to Yucca Mountain. The source tables in the database are compendiums of information from many diverse sources including: radionuclide quantities for each waste type; route and route characteristics for rail, legal-weight truck, heavy haul. truck, and barge transport options; state-specific accident and fatality rates for routes selected for analysis; packaging and shipment data by waste type; unit risk factors; the complex behavior of the packaged waste forms in severe transport accidents; and the effects of exposure to radiation or the isotopic specific effects of radionclides should they be released in severe transportation accidents. The database works together with the codes RADTRAN (Neuhauser, et al, 1994) and RISKlND (Yuan, et al, 1995) to calculate incident-free dose and accident risk. For the incident-free transportation scenario, the database uses RADTRAN and RISKIND-generated data to calculate doses to offlink populations, onlink populations, people at stops, crews, inspectors, workers at intermodal transfer stations, guards at overnight stops, and escorts, as well as non-radioactive pollution health effects. For accident scenarios, the database uses RADTRAN-generated data to calculate dose risks based on ingestion, inhalation, resuspension, immersion (cloudshine), and groundshine as

  9. Supplemental Performance Analyses for Igneous Activity and Human Intrusion at the Potential High-Level Nuclear Waste Repository at Yucca Mountain

    SciTech Connect

    Swift, P.; Gaither, K.; Freeze, G.; McCord, J.; Kalinich, D.; Saulnier, G.; Statham, W.

    2002-02-26

    The U.S. Department of Energy (DOE) is considering the possible recommendation of a site at Yucca Mountain, Nevada, for the potential development of a geologic repository for the disposal of high-level radioactive waste and spent nuclear fuel. Consequences of hypothetical disruption of the Yucca Mountain site by igneous activity or human intrusion have been evaluated in the Yucca Mountain Science and Engineering Report (S&ER) (1), which presents technical information supporting the consideration of the possible site recommendation. Since completion of the S&ER, supplemental analyses have examined possible impacts of new information and alternative assumptions on the estimates of the consequences of these events. Specifically, analyses of the consequences of igneous disruption address uncertainty regarding: (1) the impacts of changes in the repository footprint and waste package spacing on the probability of disruption; (2) impacts of alternative assumptions about the appropriat e distribution of future wind speeds to use in the analysis; (3) effects of alternative assumptions about waste particle sizes; and (4) alternative assumptions about the number of waste packages damaged by igneous intrusion; and (5) alternative assumptions about the exposure pathways and the biosphere dose conversion factors used in the analysis. Additional supplemental analyses, supporting the Final Environmental Impact Statement (FEIS), have examined the results for both igneous disruption and human intrusion, recalculated for a receptor group located 18 kilometers (km) from the repository (the location specified in 40 CFR 197), rather than at the 20 km distance used in the S&ER analyses.

  10. Groundwater flow modeling of periods with periglacial and glacial climate conditions for the safety assessment of the proposed high-level nuclear waste repository site at Forsmark, Sweden

    NASA Astrophysics Data System (ADS)

    Vidstrand, Patrik; Follin, Sven; Selroos, Jan-Olof; Näslund, Jens-Ove

    2014-09-01

    The impact of periglacial and glacial climate conditions on groundwater flow in fractured crystalline rock is studied by means of groundwater flow modeling of the Forsmark site, which was recently proposed as a repository site for the disposal of spent high-level nuclear fuel in Sweden. The employed model uses a thermal-hydraulically coupled approach for permafrost modeling and discusses changes in groundwater flow implied by the climate conditions found over northern Europe at different times during the last glacial cycle (Weichselian glaciation). It is concluded that discharge of particles released at repository depth occurs very close to the ice-sheet margin in the absence of permafrost. If permafrost is included, the greater part discharges into taliks in the periglacial area. During a glacial cycle, hydraulic gradients at repository depth reach their maximum values when the ice-sheet margin passes over the site; at this time, also, the interface between fresh and saline waters is distorted the most. The combined effect of advances and retreats during several glaciations has not been studied in the present work; however, the results indicate that hydrochemical conditions at depth in the groundwater flow model are almost restored after a single event of ice-sheet advance and retreat.

  11. Effects on groundwater flow of abandoned engineered structures for the safety assessment of the proposed high-level nuclear waste repository site at Forsmark, Sweden

    NASA Astrophysics Data System (ADS)

    Bockgård, Niclas; Marsic, Niko; Follin, Sven

    2014-09-01

    Effects on groundwater flow of abandoned engineered structures in relation to a potential geological repository for spent high-level nuclear fuel in fractured crystalline rock at the Forsmark site, Sweden, are studied by means of numerical modeling. The effects are analyzed by means of particle tracking, and transport-related performance measures are calculated. The impacts of abandoned, partially open repository tunnels are studied for two situations with different climate conditions: a "temperate" climate case with present-day boundary conditions, and a generic future "glacial" climate case with an ice sheet covering the repository. Then, the impact of abandoned open boreholes drilled through the repository is studied for present-day climate conditions. It is found that open repository tunnels and open boreholes can act as easy pathways from repository level to the ground surface; hence, they can attract a considerable proportion of particles released in the model at deposition hole positions within the repository. The changed flow field and flow paths cause some changes in the studied performance measures, i.e., increased flux at the deposition holes and decreased transport lengths and flow-related transport resistances. However, these effects are small and the transport resistance values are still high.

  12. Multi-scale groundwater flow modeling during temperate climate conditions for the safety assessment of the proposed high-level nuclear waste repository site at Forsmark, Sweden

    NASA Astrophysics Data System (ADS)

    Joyce, Steven; Hartley, Lee; Applegate, David; Hoek, Jaap; Jackson, Peter

    2014-09-01

    Forsmark in Sweden has been proposed as the site of a geological repository for spent high-level nuclear fuel, to be located at a depth of approximately 470 m in fractured crystalline rock. The safety assessment for the repository has required a multi-disciplinary approach to evaluate the impact of hydrogeological and hydrogeochemical conditions close to the repository and in a wider regional context. Assessing the consequences of potential radionuclide releases requires quantitative site-specific information concerning the details of groundwater flow on the scale of individual waste canister locations (1-10 m) as well as details of groundwater flow and composition on the scale of groundwater pathways between the facility and the surface (500 m to 5 km). The purpose of this article is to provide an illustration of multi-scale modeling techniques and the results obtained when combining aspects of local-scale flows in fractures around a potential contaminant source with regional-scale groundwater flow and transport subject to natural evolution of the system. The approach set out is novel, as it incorporates both different scales of model and different levels of detail, combining discrete fracture network and equivalent continuous porous medium representations of fractured bedrock.

  13. Modeling of strongly heat-driven flow processes at a potential high-level nuclear waste repository at Yucca Mountain, Nevada

    SciTech Connect

    Pruess, K.; Tsang, Y.

    1993-01-01

    Two complementary numerical models for analyzing high-level nuclear waste emplacement at Yucca Mountain have been developed. A vertical cross-sectional (X-Z) model permits a realistic representation of hydrogeologic features, such as alternating tilting layers of welded and non-welded tuffs. fault zones, and surface topography. An alternative radially symmetric (R-Z) model is more limited in its ability to describe the hydrogeology of the site, but is better suited to model heat transfer in the host rock. Our models include a comprehensive description of multiphase fluid and heat flow processes, including strong enhancements of vapor diffusion from pore-level phase change effects. The neighborhood of the repository is found to partially dry out from the waste heat. A condensation halo of large liquid saturation forms around the drying zone, from which liquid flows downward at large rates. System response to infiltration from the surface and to ventilation of mined openings is evaluated. The impact of the various flow processes on the waste isolation capabilities of the site is discussed.

  14. Managing Electrochemical Noise Data by Exception Application of an On Line EN Data Analysis Technique to Data From a High Level Nuclear Waste Tank

    SciTech Connect

    EDGEMON, G.L.

    2003-11-13

    Electrochemical noise has been used a t the Hanford Site for a number of years to monitor in real time for pitting corrosion and stress corrosion cracking (SCC) mechanisms in high level nuclear waste tanks. Currently the monitoring technique has only been implemented on three of the 177 underground storage tanks on the site. Widespread implementation of the technique has been held back for of a number of reasons, including issues around managing the large volume of data associated with electrochemical noise and the complexity of data analysis. Expert review of raw current and potential measurements is the primary form of data analysis currently used at the Hanford site. This paper demonstrates the application of an on-line data filtering and analysis technique that could allow data from field applications of electrochemical noise to be managed by exception, transforming electrochemical noise data into a process parameter and focusing data analysis efforts on the important data. Results of the analysis demonstrate a data compression rate of 95%; that is, only 5% of the data would require expert analysis if such a technique were implemented. It is also demonstrated that this technique is capable of identifying key periods where localized corrosion activity is apparent.

  15. Progress in evaluation of radionuclide geochemical information developed by DOE high-level nuclear waste repository site projects: Report for April 1986--September 1987

    SciTech Connect

    Meyer, R.E.; Arnold, W.D.; Blencoe, J.G.; O`Kelley, G.D.; Land, J.F.

    1988-07-01

    During this report period, all experiments were conducted with tuff from the proposed high-level nuclear waste site at Yucca Mountain, Nevada. Batch sorption ratio determinations were conducted for strontium, cesium, uranium, and technetium onto samples of tuff using real and synthetic groundwater J-13. There were no significant differences in sorption ratios in experiments with real and synthetic groundwater. Columns were tested by determination of elution curves in J-13 containing tritium and technetium as the TcO{sub 4}/sup {minus}/ ion. For strontium and cesium, fairly good correlation between values of the sorption ratio obtained by the two methods was observed. Little technetium sorption was observed with either method. The elution peaks obtained with neptunium and uranium were asymmetrical and the shapes were often complex, observations which suggest irreversibilities in the sorption reaction. Synthetic groundwater J-13 was slowly dripped onto a slab of tuff maintained at 95--100{degree}C, and the result was a thin encrustation of solids on the slab as the water evaporated. Fresh J-13 groundwater was then allowed to contact the encrustation in a vessel maintained at 90{degree}C. The principal result of the experiment was a significant loss of calcium and magnesium from the fresh J-13 groundwater. 13 refs. 25 figs., 9 tabs.

  16. A literature review of coupled thermal-hydrologic-mechanical-chemical processes pertinent to the proposed high-level nuclear waste repository at Yucca Mountain

    SciTech Connect

    Manteufel, R.D.; Ahola, M.P.; Turner, D.R.; Chowdhury, A.H.

    1993-07-01

    A literature review has been conducted to determine the state of knowledge available in the modeling of coupled thermal (T), hydrologic (H), mechanical (M), and chemical (C) processes relevant to the design and/or performance of the proposed high-level waste (HLW) repository at Yucca Mountain, Nevada. The review focuses on identifying coupling mechanisms between individual processes and assessing their importance (i.e., if the coupling is either important, potentially important, or negligible). The significance of considering THMC-coupled processes lies in whether or not the processes impact the design and/or performance objectives of the repository. A review, such as reported here, is useful in identifying which coupled effects will be important, hence which coupled effects will need to be investigated by the US Nuclear Regulatory Commission in order to assess the assumptions, data, analyses, and conclusions in the design and performance assessment of a geologic reposit``. Although this work stems from regulatory interest in the design of the geologic repository, it should be emphasized that the repository design implicitly considers all of the repository performance objectives, including those associated with the time after permanent closure. The scope of this review is considered beyond previous assessments in that it attempts with the current state-of-knowledge) to determine which couplings are important, and identify which computer codes are currently available to model coupled processes.

  17. U.S. Nuclear Regulatory Commission Review of U.S. Department of Energy Non-High Level Waste Determination for Idaho National Laboratory Tank Farm Facility

    SciTech Connect

    Barr, C.S.; Yin, X.; Camper, L.W.; Whited, A.R.; Dinwiddie, C.L.; Howard, L.D.; Pabalan, R.T.; Pickett, D.

    2007-07-01

    The National Defense Authorization Act for Fiscal Year 2005 (NDAA) authorized the United States Department of Energy (DOE) to determine whether certain radioactive waste related to the reprocessing of spent nuclear fuel is not high-level-waste (HLW). The NDAA applies to DOE facilities in the States of South Carolina and Idaho. DOE must consult with the United States Nuclear Regulatory Commission (NRC) as part of its waste determination. NRC must coordinate with the affected state to monitor DOE's disposal actions to assess compliance with 10 CFR 61, Subpart C, performance objectives. The performance objectives in 10 CFR Part 61, Subpart C, contain requirements for protection of the public, inadvertent intruders, individuals during operations, and stability of the disposal site after closure. In September 2005, DOE submitted to NRC a draft non-HLW determination for waste incidental to reprocessing, including sodium-bearing waste [note: Sodium-bearing waste is a generic term used to describe radioactive wastes comprised of second- and third-cycle extraction fluid and decontamination fluids. This waste contains less activity and generally poses less risk than first-cycle extraction fluid (first-cycle extraction fluid contains most of the fission products)] (SBW) stored in the Idaho Nuclear Technology and Engineering Center tank farm facility (INTEC TFF) at the Idaho National Laboratory (INL). DOE plans to grout the underground tanks and concrete vaults that house these tanks to stabilize the waste in situ. DOE prepared a waste determination to demonstrate compliance with NDAA criteria, including a supporting performance assessment to demonstrate compliance with the performance objectives. To carry out its consultative role required by the NDAA, NRC uses a risk-informed, performance-based approach in its review of DOE waste determinations and performance assessments to focus on the key natural and engineered system features needed to support its compliance

  18. A TRANSPORTATION RISK ASSESSMENT TOOL FOR ANALYZING THE TRANSPORT OF SPENT NUCLEAR FUEL AND HIGH-LEVEL RADIOACTIVE WASTE TO THE PROPOSED YUCCA MOUNTAIN REPOSITORY

    SciTech Connect

    NA

    2001-02-15

    The Yucca Mountain Draft Environmental Impact Statement (DEIS) analysis addressed the potential for transporting spent nuclear fuel and high-level radioactive waste from 77 origins for 34 types of spent fuel and high-level radioactive waste, 49,914 legal weight truck shipments, and 10,911 rail shipments. The analysis evaluated transportation over 59,250 unique shipment links for travel outside Nevada (shipment segments in urban, suburban or rural zones by state), and 22,611 links in Nevada. In addition, the analysis modeled the behavior of 41 isotopes, 1091 source terms, and used 8850 food transfer factors (distinct factors by isotope for each state). The analysis also used mode-specific accident rates for legal weight truck, rail, and heavy haul truck by state, and barge by waterway. This complex mix of data and information required an innovative approach to assess the transportation impacts. The approach employed a Microsoft{reg_sign} Access database tool that incorporated data from many sources, including unit risk factors calculated using the RADTRAN IV transportation risk assessment computer program. Using Microsoft{reg_sign} Access, the analysts organized data (such as state-specific accident and fatality rates) into tables and developed queries to obtain the overall transportation impacts. Queries are instructions to the database describing how to use data contained in the database tables. While a query might be applied to thousands of table entries, there is only one sequence of queries that is used to calculate a particular transportation impact. For example, the incident-free dose to off-link populations in a state is calculated by a query that uses route segment lengths for each route in a state that could be used by shipments, populations for each segment, number of shipments on each segment, and an incident-free unit risk factor calculated using RADTRAN IV. In addition to providing a method for using large volumes of data in the calculations, the

  19. Radiation-Induced Defects in Kaolinite as Tracers of Past Occurrence of Radionuclides in a Natural Analogue of High Level Nuclear Waste Repository

    NASA Astrophysics Data System (ADS)

    Allard, T.; Fourdrin, C.; Calas, G.

    2007-05-01

    Understanding the processes controlling migrations of radioelements at the Earth's surface is an important issue for the long-term safety assessment of high level nuclear waste repositories (HLNWR). Evidence of past occurrence and transfer of radionuclides can be found using radiation-induced defects in minerals. Clay minerals are particularly relevant because of their widespread occurrence at the Earth's surface and their finely divided nature which provides high contact area with radioactive fluids. Owing to its sensitivity to radiations, kaolinite can be used as natural, in situ dosimeter. Kaolinite is known to contain radiation-induced defects which are detected by Electron Paramagnetic Resonance. They are differentiated by their nature, their production kinetics and their thermal stability. One of these defects is stable at the scale of geological periods and provides a record of past radionuclide occurrence. Based on artificial irradiations, a methodology has been subsequently proposed to determine paleodose cumulated by kaolinite since its formation. The paleodose can be used to derive equivalent radioelement concentrations, provided that the age of kaolinite formation can be constrained. This allows quantitative reconstruction of past transfers of radioelements in natural systems. An example is given for the Nopal I U-deposit (Chihuahua, Mexico), hosted in hydrothermally altered volcanic tufs and considered as analogue of the Yucca Mountain site. The paleodoses experienced by kaolinites were determined from the concentration of defects and dosimetry parameters of experimental irradiations. Using few geochemical assumption, a equivalent U-content responsible for defects in kaolinite was calculated from the paleodose, a dose rate balance and model ages of kaolinites constrained by tectonic phases. In a former study, the ages were assumptions derived from regional tectonic events. In thepresent study, ages of mineralization events are measured from U

  20. Update to Assessment of Direct Disposal in Unsaturated Tuff of Spent Nuclear Fuel and High-Level Waste Owned by U.S. Department of Energy

    SciTech Connect

    P. D. Wheatley; R. P. Rechard

    1998-09-01

    The overall purpose of this study is to provide information and guidance to the Office of Environmental Management of the U.S. Department of Energy (DOE) about the level of characterization necessary to dispose of DOE-owned spent nuclear fuel (SNF). The disposal option modeled was codisposal of DOE SNF with defense high-level waste (DHLW). A specific goal was to demonstrate the influence of DOE SNF, expected to be minor, in a predominately commercial repository using modeling conditions similar to those currently assumed by the Yucca Mountain Project (YMP). A performance assessment (PA) was chosen as the method of analysis. The performance metric for this analysis (referred to as the 1997 PA) was dose to an individual; the time period of interest was 100,000 yr. Results indicated that cumulative releases of 99Tc and 237Np (primary contributors to human dose) from commercial SNF exceed those of DOE SNF both on a per MTHM and per package basis. Thus, if commercial SNF can meet regulatory performance criteria for dose to an individual, then the DOE SNF can also meet the criteria. This result is due in large part to lower burnup of the DOE SNF (less time for irradiation) and to the DOE SNF's small percentage of the total activity (1.5%) and mass (3.8%) of waste in the potential repository. Consistent with the analyses performed for the YMP, the 1997 PA assumed all cladding as failed, which also contributed to the relatively poor performance of commercial SNF compared to DOE SNF.

  1. Remote automatic plasma arc-closure welding of a dry-storage canister for spent nuclear fuel and high-level radioactive waste

    SciTech Connect

    Sprecace, R.P.; Blankenship, W.P.

    1982-12-31

    A carbon steel storage canister has been designed for the dry encapsulation of spent nuclear fuel assemblies or of logs of vitrified high level radioactive waste. The canister design is in conformance with the requirements of the ASME Code, Section III, Division 1 for a Class 3 vessel. The canisters will be loaded and sealed as part of a completely remote process sequence to be performed in the hot bay of an experimental encapsulation facility at the Nevada Test Site. The final closure to be made is a full penetration butt weld between the canister body, a 12.75-in O.D. x 0.25-in wall pipe, and a mating semiellipsoidal closure lid. Due to a combination of design, application and facility constraints, the closure weld must be made in the 2G position (canister vertical). The plasma arc welding system is described, and the final welding procedure is described and discussed in detail. Several aspects and results of the procedure development activity, which are of both specific and general interest, are highlighted; these include: The critical welding torch features which must be exactly controlled to permit reproducible energy input to, and gas stream interaction with, the weld puddle. A comparison of results using automatic arc voltage control with those obtained using a mechanically fixed initial arc gap. The optimization of a keyhole initiation procedure. A comparison of results using an autogenous keyhole closure procedure with those obtained using a filler metal addition. The sensitivity of the welding process and procedure to variations in joint configuration and dimensions and to variations in base metal chemistry. Finally, the advantages and disadvantages of the plasma arc process for this application are summarized from the current viewpoint, and the applicability of this process to other similar applications is briefly indicated.

  2. Final Systems Development Report for the Clark County Socioeconomic Impact Assessment of the Proposed High-Level Nuclear Waste Repository at Yucca Mountain, NV

    SciTech Connect

    1992-06-18

    The Systems Development Report represents the third major step in the Clark County Socioeconomic Impact Assessment of the Proposed High-Level Nuclear Waste Repository at Yucca Mound Nevada. The first of these steps was to forge a Research Design that would serve as a guide for the overall research process. The second step was the construction of the Base Case, the purpose of which was to describe existing conditions in Clark County in the specified analytic areas of Economic-Demographic/Fiscal, Emergency Planning and Management, Transportation and Sociocultural analysis. The base case description will serve as a basis for assessing changes in these topic areas that might result from the Yucca Mountain project. These changes will be assessed by analyzing conditions with and without repository development in the county. Prior to performing such assessments, however, the snapshot type of data found in the base case must be operationalized or systematized to allow for more dynamic data utilization. In other words, a data system that can be used to analyze the consequences of the introduction of different variables (or variable values) in the Clark County context must be constructed. Such a system must be capable of being updated through subsequent data collection and monitoring efforts to both provide a rolling base case and supply information necessary to construct trend analyses. For example, during the Impact Assessment phase of the study process, the without repository analysis is accomplished by analyzing growth for the county given existing conditions and likely trends. These data are then compared to the with Yucca Mountain project conditions anticipated for the county. Similarly, once the emergency planning management and response needs associated with the repository are described, these needs will be juxtaposed against existing (and various future) capacity(ies) in order to determine the nature and magnitude of impacts in this analytic area. Analogous tasks

  3. Progress in evaluation of radionuclide geochemical information developed by DOE high-level nuclear waste repository site projects: Report for April 1986-September 1987

    SciTech Connect

    Meyer, R.E.; Arnold, W.D.; Blencoe, J.G.; O`Kelley, G.D.; Land, J.F.

    1988-02-01

    Experiments were conducted with tuff from the proposed high-level nuclear waste site at Yucca Mountain, Nevada. Batch sorption ratio determinations were conducted for strontium, cesium, uranium, and technetium onto samples of tuff using real and synthetic groundwater J-13. There were no significant differences in sorption ratios in experiments with real and synthetic groundwater. Columns 1 cm in diameter and about 5 cm long were constructed, and experiments were conducted with the objective of correlating the results of batch and the column experiments. The characteristics of the columns were tested by determination of elution curves in J-13 containing tritium and technetium as the TcO{sub 4}{sup -} ion. For strontium and cesium, fairly good correlation between values of the sorption ratio obtained by the two methods was observed. Little or no technetium sorption was observed with either method. The elution peaks obtained with neptunium and uranium were asymmetrical and the shapes were often complex, observations which suggest irreversibilities in the sorption reaction. An experiment was performed to provide information on the compositions of the first groundwaters that will contact waste canisters in a tuff-hosted repository after very near field temperatures have cooled to below 100{degree}C. Synthetic groundwater J-13 was slowly dripped onto a slab of tuff maintained at 95-100{degree}C, and the result was a thin encrustation of solids on the slab as the water evaporated. Fresh J-13 groundwater was then allowed to contact the encrustation in a vessel maintained at 90{degree}C. The principal result of the experiment was a significant loss of calcium and magnesium from the fresh J-13 groundwater.

  4. Final base case community analysis: Indian Springs, Nevada for the Clark County socioeconomic impact assessment of the proposed high- level nuclear waste repository at Yucca Mountain, Nevada

    SciTech Connect

    1992-06-18

    This document provides a base case description of the rural Clark County community of Indian Springs in anticipation of change associated with the proposed high-level nuclear waste repository at Yucca Mountain. As the community closest to the proposed site, Indian Springs may be seen by site characterization workers, as well as workers associated with later repository phases, as a logical place to live. This report develops and updates information relating to a broad spectrum of socioeconomic variables, thereby providing a `snapshot` or `base case` look at Indian Springs in early 1992. With this as a background, future repository-related developments may be analytically separated from changes brought about by other factors, thus allowing for the assessment of the magnitude of local changes associated with the proposed repository. Given the size of the community, changes that may be considered small in an absolute sense may have relatively large impacts at the local level. Indian Springs is, in many respects, a unique community and a community of contrasts. An unincorporated town, it is a small yet important enclave of workers on large federal projects and home to employees of small- scale businesses and services. It is a rural community, but it is also close to the urbanized Las Vega Valley. It is a desert community, but has good water resources. It is on flat terrain, but it is located within 20 miles of the tallest mountains in Nevada. It is a town in which various interest groups diverge on issues of local importance, but in a sense of community remains an important feature of life. Finally, it has a sociodemographic history of both surface transience and underlying stability. If local land becomes available, Indian Springs has some room for growth but must first consider the historical effects of growth on the town and its desired direction for the future.

  5. Nepheline Crystallization in Nuclear Waste Glasses: Progress toward acceptance of high-alumina formulations

    SciTech Connect

    McCloy, John S.; Schweiger, Michael J.; Rodriguez, Carmen P.; Vienna, John D.

    2011-09-01

    We have critically compiled and analyzed historical data for investigating the quantity of nepheline (NaAlSiO4) precipitation as a function of composition in simulated nuclear waste glasses. To understand composition we used two primary methods: 1) investigating the Al2O3-SiO2-Na2O ternary with filtering for different B2O3 levels and 2) creating a quadrant system consisting of compositions reduced to two metric numbers. These metrics are 1) the nepheline discriminator (ND) which depends only on the SiO2 content by weight normalized to the total weight of the Al2O3-SiO2-Na2O sub-mixture and 2) the optical basicity (OB) which contains contributions from all constituents in the glass. Nepheline precipitation is expected to be suppressed at high SiO2 levels (ND >0.62) or at low basicities (OB <0.55 to 0.57). Changes in sodium aluminosilicate glass OB due to additions of CaO and B2O3 correlate with observed effects on nepheline formation. We propose that additional composition space is available for formulating high-waste-loading, high-Al¬2O3 nuclear waste glasses when Na2O levels are less than ~0.125 (normalized by weight on the Al2O3-SiO2-Na2O sub-mixture). However, this compositional space is considerably extended to higher Na2O levels when adding >5 wt% B2O3. The OB concept can help further refine regions of nepheline-free glass formation.

  6. Ion track reconstruction in 3D using alumina-based fluorescent nuclear track detectors.

    PubMed

    Niklas, M; Bartz, J A; Akselrod, M S; Abollahi, A; Jäkel, O; Greilich, S

    2013-09-21

    Fluorescent nuclear track detectors (FNTDs) based on Al2O3: C, Mg single crystal combined with confocal microscopy provide 3D information on ion tracks with a resolution only limited by light diffraction. FNTDs are also ideal substrates to be coated with cells to engineer cell-fluorescent ion track hybrid detectors (Cell-Fit-HD). This radiobiological tool enables a novel platform linking cell responses to physical dose deposition on a sub-cellular level in proton and heavy ion therapies. To achieve spatial correlation between single ion hits in the cell coating and its biological response the ion traversals have to be reconstructed in 3D using the depth information gained by the FNTD read-out. FNTDs were coated with a confluent human lung adenocarcinoma epithelial (A549) cell layer. Carbon ion irradiation of the hybrid detector was performed perpendicular and angular to the detector surface. In situ imaging of the fluorescently labeled cell layer and the FNTD was performed in a sequential read-out. Making use of the trajectory information provided by the FNTD the accuracy of 3D track reconstruction of single particles traversing the hybrid detector was studied. The accuracy is strongly influenced by the irradiation angle and therefore by complexity of the FNTD signal. Perpendicular irradiation results in highest accuracy with error of smaller than 0.10°. The ability of FNTD technology to provide accurate 3D ion track reconstruction makes it a powerful tool for radiobiological investigations in clinical ion beams, either being used as a substrate to be coated with living tissue or being implanted in vivo. PMID:23965401

  7. Ion track reconstruction in 3D using alumina-based fluorescent nuclear track detectors

    NASA Astrophysics Data System (ADS)

    Niklas, M.; Bartz, J. A.; Akselrod, M. S.; Abollahi, A.; Jäkel, O.; Greilich, S.

    2013-09-01

    Fluorescent nuclear track detectors (FNTDs) based on Al2O3: C, Mg single crystal combined with confocal microscopy provide 3D information on ion tracks with a resolution only limited by light diffraction. FNTDs are also ideal substrates to be coated with cells to engineer cell-fluorescent ion track hybrid detectors (Cell-Fit-HD). This radiobiological tool enables a novel platform linking cell responses to physical dose deposition on a sub-cellular level in proton and heavy ion therapies. To achieve spatial correlation between single ion hits in the cell coating and its biological response the ion traversals have to be reconstructed in 3D using the depth information gained by the FNTD read-out. FNTDs were coated with a confluent human lung adenocarcinoma epithelial (A549) cell layer. Carbon ion irradiation of the hybrid detector was performed perpendicular and angular to the detector surface. In situ imaging of the fluorescently labeled cell layer and the FNTD was performed in a sequential read-out. Making use of the trajectory information provided by the FNTD the accuracy of 3D track reconstruction of single particles traversing the hybrid detector was studied. The accuracy is strongly influenced by the irradiation angle and therefore by complexity of the FNTD signal. Perpendicular irradiation results in highest accuracy with error of smaller than 0.10°. The ability of FNTD technology to provide accurate 3D ion track reconstruction makes it a powerful tool for radiobiological investigations in clinical ion beams, either being used as a substrate to be coated with living tissue or being implanted in vivo.

  8. Hot isostatically-pressed aluminosilicate glass-ceramic with natural crystalline analogues for immobilizing the calcined high-level nuclear waste at the Idaho Chemical Processing Plant

    SciTech Connect

    Raman, S.

    1993-12-01

    The additives Si, Al, MgO, P{sub 2}O{sub 5} were mechanically blended with fluorinelsodium calcine in varying proportions. The batches were vacuum sealed in stainless steel canisters and hot isostatically pressed at 20,000 PSI and 1000 C for 4 hours. The resulting suite of glass-ceramic waste forms parallels the natural rocks in microstructural and compositional heterogeneity. Several crystalline phases ar analogous in composition and structure to naturally occurring minerals. Additional crystalline phases are zirconia and Ca-Mg borate. The glasses are enriched in silica and alumina. Approximately 7% calcine elements occur dissolved in this glass and the total glass content in the waste forms averages 20 wt%. The remainder of the calcine elements are partitioned into crystalline phases at 75 wt% calcine waste loading. The waste forms were tested for chemical durability in accordance with the MCC1-test procedure. The leach rates are a function of the relative proportions of additives and calcine, which in turn influence the composition and abundances of the glass and crystalline phases. The DOE leach rate criterion of less than 1 g/m{sup 2}-day is met by all the elements B, Cs and Na are increased by lowering the melt viscosity. This is related to increased crystallization or devitrification with increases in MgO addition. This exploratory work has shown that the increases in waste loading occur by preferred partitioning of the calcine components among crystalline and glass phases. The determination of optimum processing parameters in the form of additive concentration levels, homogeneous blending among the components, and pressure-temperature stabilities of phases must be continued to eliminate undesirable effects of chemical composition, microstructure and glass devitrification.

  9. EPR and electron-nuclear double-resonance studies of an F/sup +/ center in sodium, potassium, and lithium. beta. -alumina

    SciTech Connect

    Kurtz, S.R.; Stinson, D.G.; Stapleton, H.J.; Abraham, M.M.

    1981-11-01

    EPR and electron-nuclear double-resonance (ENDOR) data from F/sup +/ centers in the conduction planes of sodium, potassium and lithium ..beta..-alumina are presented. The low-temperature Ku-band ENDOR spectra from these fast ionic conductors consist of sharp resonances from distant nuclei and broad, unresolved signals from nearest-neighbor aluminum and nearby Na, K, or Li cations in the conduction plane. The Na data are consistent with x-band ENDOR results of others. The K and Li data reveal the existence of a second inequivalent F/sup +/ center in these materials. The shape and breadth of the Na ENDOR signal can be simulated assuming that: (1) both Beevers-Ross and mid-oxygen sites are occupied, (2) the F/sup +/-ligand hyperfine interaction varies with distance as 1/R/sup 3/, and (3) there exists a Gaussian distribution of hyperfine couplings which is consistent with a 0.3-A tunneling distance inferred for Na ions from dielectric susceptibility data on Na ..beta..-alumina.

  10. Systems study of the feasibility of high-level nuclear waste fractionation for thermal stress control in a geologic repository: appendices

    SciTech Connect

    McKee, R.W.; Elder, H.K.; McCallum, R.F.; Silviera, D.J.; Swanson, J.L.; Wiles, L.E.

    1983-06-01

    This study assesses the benefits and costs of fractionating the cesium and strontium (Cs/Sr) components in commercial high-level waste (HLW) to a separate waste stream for the purpose of reducing geologic-repository thermal stresses in the region of the HLW. The major conclusion is that the Cs/Sr fractionation concept offers the prospect of a substantial total system cost advantage for HLW disposal if reduced HLW package temperatures in a basalt repository are desired. However there is no cost advantage if currently designated maximum design temperatures are acceptable. Aging the HLW for 50 to 100 years can accomplish similar results at equivalent or lower costs. Volume II contains appendices for: (1) thermal analysis supplement; (2) fractionation process experimental results supplement; (3) cost analysis supplement; and (4) radiological risk analysis supplement.

  11. Implications of theories of asteroid and comet impact for policy options for management of spent nuclear fuel and high-level radioactive wastes

    USGS Publications Warehouse

    Trask, Newell J.

    1994-01-01

    Concern with the threat posed by terrestrial asteroid and comet impacts has heightened as the catastrophic consequences of such events have become better appreciated. Although the probabilities of such impacts are very small, a reasonable question for debate is whether such phenomena should be taken into account in deciding policy for the management of spent fuel and high-level radioactive waste. The rate at which asteroid or comet impacts would affect areas of surface storage of radioactive waste is about the same as the estimated rate at which volcanic activity would affect the Yucca Mountain area. The Underground Retrievable Storage (URS) concept could satisfactorily reduce the risk from cosmic impact with its associated uncertainties in addition to providing other benefits described by previous authors.

  12. Long-term management of liquid high-level radioactive wastes stored at the Western New York Nuclear Service Center, West Valley

    NASA Astrophysics Data System (ADS)

    1981-07-01

    Environmental implications of possible alternatives for long-term management of the liquid high-level radioactive wastes stored in underground tanks in West Valley, New York were assessed and compared. Four basic alternatives, as well as options within these alternatives, considered in the EIS: (1) onsite processing to a terminal waste form for shipment and disposal in a federa repository; (2) onsite conversion to a solid interim form for shipment to a federal waste facility for later processing to a terminal form and shipment and subsequent disposal in a federal repository; (3) mixing the liquid wastes with cement and other additives, pouring it back into the existing tanks, and leaving onsite; and (4) no action (continued storage of the wastes in liquid form in the underground tanks at West Valley). Mitigative measures for environmental impacts were be required.

  13. Performance assessment of the direct disposal in unsaturated tuff of spent nuclear fuel and high-level waste owned by U.S. Department of Energy. Volume 1: Executive summary

    SciTech Connect

    Rechard, R.P.

    1995-03-01

    This assessment studied the performance of high-level radioactive waste and spent nuclear fuel in a hypothetical repository in unsaturated tuff. The results of this 10-month study are intended to help guide the Office of Environment Management of the US Department of Energy (DOE) on how to prepare its wastes for eventual permanent disposal. The waste forms comprised spent fuel and high-level waste currently stored at the Idaho National Engineering Laboratory (INEL) and the Hanford reservation. About 700 metric tons heavy metal (MTHM) of the waste under study is stored at INEL, including graphite spent nuclear fuel, highly enriched uranium spent fuel, low enriched uranium spent fuel, and calcined high-level waste. About 2,100 MTHM of weapons production fuel, currently stored on the Hanford reservation, was also included. The behavior of the waste was analyzed by waste form and also as a group of waste forms in the hypothetical tuff repository. When the waste forms were studied together, the repository was assumed also to contain about 9,200 MTHM high-level waste in borosilicate glass from three DOE sites. The addition of the borosilicate glass, which has already been proposed as a final waste form, brought the total to about 12,000 MTHM. A source term model was developed to study the wide variety of waste forms, which included radionuclides residing in 10 different matrices and up to 8 nested layers of material that might react with water. The possibility and consequences of critical conditions occurring in or near containers of highly enriched uranium spent nuclear fuel were also studied.

  14. FINAL REPORT. ANALYSIS OF SURFACE LEACHING PROCESSES IN VITRIFIED HIGH-LEVEL NUCLEAR WASTES USING IN-SITU RAMAN IMAGING AND ATOMISTIC MODELING

    EPA Science Inventory

    The in-situ analysis of surface conditions of vitrified nuclear wastes can provide animportant check of the burial status of these radioactive objects without risk of radiationexposure. This check could be conducted over time and be used to monitor conditions in a storage site....

  15. Extension of sensitivity and uncertainty analysis for long term dose assessment of high level nuclear waste disposal sites to uncertainties in the human behaviour.

    PubMed

    Albrecht, Achim; Miquel, Stéphan

    2010-01-01

    Biosphere dose conversion factors are computed for the French high-level geological waste disposal concept and to illustrate the combined probabilistic and deterministic approach. Both (135)Cs and (79)Se are used as examples. Probabilistic analyses of the system considering all parameters, as well as physical and societal parameters independently, allow quantification of their mutual impact on overall uncertainty. As physical parameter uncertainties decreased, for example with the availability of further experimental and field data, the societal uncertainties, which are less easily constrained, particularly for the long term, become more and more significant. One also has to distinguish uncertainties impacting the low dose portion of a distribution from those impacting the high dose range, the latter having logically a greater impact in an assessment situation. The use of cumulative probability curves allows us to quantify probability variations as a function of the dose estimate, with the ratio of the probability variation (slope of the curve) indicative of uncertainties of different radionuclides. In the case of (135)Cs with better constrained physical parameters, the uncertainty in human behaviour is more significant, even in the high dose range, where they increase the probability of higher doses. For both radionuclides, uncertainties impact more strongly in the intermediate than in the high dose range. In an assessment context, the focus will be on probabilities of higher dose values. The probabilistic approach can furthermore be used to construct critical groups based on a predefined probability level and to ensure that critical groups cover the expected range of uncertainty. PMID:19758732

  16. Effects of Fuel to Synthesis of CaTiO3 by Solution Combustion Synthesis for High-Level Nuclear Waste Ceramics.

    PubMed

    Jung, Choong-Hwan; Kim, Yeon-Ku; Han, Young-Min; Lee, Sang-Jin

    2016-02-01

    A solution combustion process for the synthesis of perovskite (CaTiO3) powders is described. Perovskite is one of the crystalline host matrics for the disposal of high-level radioactive wastes (HLW) because it immobilizes Sr and Lns elements by forming solid solutions. Solution combustion synthesis, which is a self-sustaining oxi-reduction reaction between nitrate and organic fuel, the exothermic reaction, and the heat evolved convert the precursors into their corresponding oxide products above 1100 degrees C in air. To investigate the effects of amino acid on the combustion reaction, various types of fuels were used; a glycine, amine and carboxylic ligand mixture. Sr, La and Gd-nitrate with equivalent amounts of up to 20% of CaTiO3 were mixed with Ca and Ti nitrate and amino acid. X-ray diffraction analysis, SEM and TEM were conducted to confirm the formed phases and morphologies. While powders with an uncontrolled shape are obtained through a general oxide-route process, Ca(Sr, Lns)TiO3 powders with micro-sized soft agglomerates consisting of nano-sized primary particles can be prepared using this method. PMID:27433645

  17. The Waste Package Project. Final report, July 1, 1995--February 27, 1996: Volume 1, The structural performance of the shell and fuel rods of a high level nuclear waste container

    SciTech Connect

    Ladkany, S.G.; Rajagopalan, R.

    1996-06-01

    This dissertation proposal covers research work that started in the spring of 1992. The aim of the research has been to study the structural performance and stability of proposed nuclear waste containers and the enclosed fuel rods to be used in the long term storage of High Level Nuclear Waste (HLNW). This research is in two phases, computational and experimental. The computational phase deals with the linear and nonlinear Finite Element Analysis of the different containers due to various loading conditions during normal handling conditions and due to the effect of long term corrosion while the canister is stored in the drift of a backfilled geological repository. The elastoplastic stability of the nuclear fuel rods were studied under body forces resulting from acceleration vectors at varying angles, resulting from a sudden drop of the canister at an angle onto a hard surface.

  18. Analysis of Surface Leaching Processes in Vitrified High-Level Nuclear Wastes Using In-Situ Raman Imaging and Atomistic Modeling - Final Report

    SciTech Connect

    Simmons, Joseph H.

    2001-04-24

    The in situ analysis of surface conditions of vitrified nuclear wastes can provide an important check of the burial status of radioactive objects without risk of radiation exposure. Raman spectroscopy was initially chosen as the most promising method for testing the surface conditions of glasses undergoing chemical corrosion, and was used extensively during the first year. However, it was determined that infrared reflection spectroscopy was better suited to this particular need and was used for the remaining two years to investigate the surface corrosion behavior of model silicate glasses for extension to nuclear waste glasses. The developed methodology is consistent with the known theory of optical propagation of dielectric media and uses the Kramers-Kronig formalism. The results show that it is possible to study the corrosion of glass by analyzing the glass surface using reflection fast Fourier infrared measurements and the newly developed ''dispersion analysis method.'' The data show how this analysis can be used to monitor the corrosion behavior of vitrified waste glasses over extended periods of storage.

  19. Optimizing High Level Waste Disposal

    SciTech Connect

    Dirk Gombert

    2005-09-01

    If society is ever to reap the potential benefits of nuclear energy, technologists must close the fuel-cycle completely. A closed cycle equates to a continued supply of fuel and safe reactors, but also reliable and comprehensive closure of waste issues. High level waste (HLW) disposal in borosilicate glass (BSG) is based on 1970s era evaluations. This host matrix is very adaptable to sequestering a wide variety of radionuclides found in raffinates from spent fuel reprocessing. However, it is now known that the current system is far from optimal for disposal of the diverse HLW streams, and proven alternatives are available to reduce costs by billions of dollars. The basis for HLW disposal should be reassessed to consider extensive waste form and process technology research and development efforts, which have been conducted by the United States Department of Energy (USDOE), international agencies and the private sector. Matching the waste form to the waste chemistry and using currently available technology could increase the waste content in waste forms to 50% or more and double processing rates. Optimization of the HLW disposal system would accelerate HLW disposition and increase repository capacity. This does not necessarily require developing new waste forms, the emphasis should be on qualifying existing matrices to demonstrate protection equal to or better than the baseline glass performance. Also, this proposed effort does not necessarily require developing new technology concepts. The emphasis is on demonstrating existing technology that is clearly better (reliability, productivity, cost) than current technology, and justifying its use in future facilities or retrofitted facilities. Higher waste processing and disposal efficiency can be realized by performing the engineering analyses and trade-studies necessary to select the most efficient methods for processing the full spectrum of wastes across the nuclear complex. This paper will describe technologies being

  20. On thermohydrologic conditions near high-level nuclear wastes emplaced in partially saturated fractured tuff: 1. Simulation studies with explicit consideration of fracture effects

    NASA Astrophysics Data System (ADS)

    Pruess, K.; Wang, J. S. Y.; Tsang, Y. W.

    1990-06-01

    We have performed modeling studies on the simultaneous transport of heat, liquid water, vapor, and air in partially saturated, fractured porous rock. Formation parameters were chosen as representative of the potential nuclear waste repository site in the Topopah Spring unit of the Yucca Mountain tuffs. The presence of fractures makes the transport problem very complex, both in terms of flow geometry and physics. The numerical simulator used for our flow calculations takes into account most of the physical effects believed to be important in multiphase fluid and heat flow. It has provisions for handling the extreme nonlinearities that arise in phase transitions, component disappearances, and capillary discontinuities at fracture faces. We model a region around an infinite linear string of nuclear waste canisters, taking into account both the discrete fractures and the porous matrix. Thermohydrologic conditions in the vicinity of the waste packages are found to depend strongly on relative permeability and capillary pressure characteristics of the fractures, which are unknown at the present time. If liquid held on the rough walls of drained fractures is assumed to be mobile, strong heat pipe effects are predicted. Under these conditions the host rock will remain in two-phase conditions right up to the emplacement hole, and formation temperatures will peak near 100°C. If it is assumed that liquid cannot move along drained fractures, the region surrounding the waste packages is predicted to dry up, and formation temperatures will rise beyond 200°C. A substantial fraction of waste heat can be removed if emplacement holes are left open and ventilated, as opposed to backfilled and sealed emplacement conditions. Comparing our model predictions with observations from in situ heater experiments reported by Zimmerman and coworkers, some intriguing similarities are noted. However, for a quantitative evaluation, additional carefully controlled laboratory and field experiments

  1. On the importance of coupled THM processes to predict the long-term response of a generic salt repository for high-level nuclear waste

    NASA Astrophysics Data System (ADS)

    Blanco Martin, L.; Rutqvist, J.; Birkholzer, J. T.

    2013-12-01

    Salt is a potential medium for the underground disposal of nuclear waste because it has several assets, in particular its ability to creep and heal fractures generated by excavation and its water and gas tightness in the undisturbed state. In this research, we focus on disposal of heat-generating nuclear waste (such as spent fuel) and we consider a generic salt repository with in-drift emplacement of waste packages and subsequent backfill of the drifts with run-of-mine crushed salt. As the natural salt creeps, the crushed salt backfill gets progressively compacted and an engineered barrier system is subsequently created. In order to evaluate the integrity of the natural and engineered barriers over the long-term, it is important to consider the coupled effects of the thermal, hydraulic and mechanical processes that take place. In particular, the results obtained so far show how the porosity reduction of the crushed salt affects the saturation and pore pressure evolution throughout the repository, both in time and space. Such compaction is induced by the stress and temperature regime within the natural salt. Also, transport properties of the host rock are modified not only by thermo-mechanically and hydraulically-induced damaged processes, but also by healing/sealing of existing fractures. In addition, the THM properties of the backfill evolve towards those of the natural salt during the compaction process. All these changes are based on dedicated laboratory experiments and on theoretical considerations [1-3]. Different scenarios are modeled and compared to evaluate the relevance of different processes from the perspective of effective nuclear waste repositories. The sensitivity of the results to some parameters, such as capillarity, is also addressed. The simulations are conducted using an updated version of the TOUGH2-FLAC3D simulator, which is based on a sequential explicit method to couple flow and geomechanics [4]. A new capability for large strains and creep

  2. High-Level Genetic Diversity and Complex Population Structure of Siberian Apricot (Prunus sibirica L.) in China as Revealed by Nuclear SSR Markers

    PubMed Central

    Wang, Zhe; Kang, Ming; Liu, Huabo; Gao, Jiao; Zhang, Zhengdong; Li, Yingyue; Wu, Rongling; Pang, Xiaoming

    2014-01-01

    Siberian apricot (Prunus sibirica L.), an ecologically and economically important tree species with a high degree of tolerance to a variety of extreme environmental conditions, is widely distributed across the mountains of northeastern and northern China, eastern and southeastern regions of Mongolia, Eastern Siberia, and the Maritime Territory of Russia. However, few studies have examined the genetic diversity and population structure of this species. Using 31 nuclear microsatellites, we investigated the level of genetic diversity and population structure of Siberian apricot sampled from 22 populations across China. The number of alleles per locus ranged from 5 to 33, with an average of 19.323 alleles. The observed heterozygosity and expected heterozygosity ranged from 0.037 to 0.874 and 0.040 to 0.924 with average values of 0.639 and 0.774, respectively. A STRUCTURE-based analysis clustered all of the populations into four genetic clusters. Significant genetic differentiation was observed between all population pairs. A hierarchical analysis of molecular variance attributed about 94% of the variation to within populations. No significant difference was detected between the wild and semi-wild groups, indicating that recent cultivation practices have had little impact on the genetic diversity of Siberian apricot. The Mantel test showed that the genetic distance among the populations was not significantly correlated with geographic distance (r = 0.4651, p = 0.9940). Our study represents the most comprehensive investigation of the genetic diversity and population structure of Siberian apricot in China to date, and it provides valuable information for the collection of genetic resources for the breeding of Siberian apricot and related species. PMID:24516551

  3. High-level genetic diversity and complex population structure of Siberian apricot (Prunus sibirica L.) in China as revealed by nuclear SSR markers.

    PubMed

    Wang, Zhe; Kang, Ming; Liu, Huabo; Gao, Jiao; Zhang, Zhengdong; Li, Yingyue; Wu, Rongling; Pang, Xiaoming

    2014-01-01

    Siberian apricot (Prunus sibirica L.), an ecologically and economically important tree species with a high degree of tolerance to a variety of extreme environmental conditions, is widely distributed across the mountains of northeastern and northern China, eastern and southeastern regions of Mongolia, Eastern Siberia, and the Maritime Territory of Russia. However, few studies have examined the genetic diversity and population structure of this species. Using 31 nuclear microsatellites, we investigated the level of genetic diversity and population structure of Siberian apricot sampled from 22 populations across China. The number of alleles per locus ranged from 5 to 33, with an average of 19.323 alleles. The observed heterozygosity and expected heterozygosity ranged from 0.037 to 0.874 and 0.040 to 0.924 with average values of 0.639 and 0.774, respectively. A STRUCTURE-based analysis clustered all of the populations into four genetic clusters. Significant genetic differentiation was observed between all population pairs. A hierarchical analysis of molecular variance attributed about 94% of the variation to within populations. No significant difference was detected between the wild and semi-wild groups, indicating that recent cultivation practices have had little impact on the genetic diversity of Siberian apricot. The Mantel test showed that the genetic distance among the populations was not significantly correlated with geographic distance (r = 0.4651, p = 0.9940). Our study represents the most comprehensive investigation of the genetic diversity and population structure of Siberian apricot in China to date, and it provides valuable information for the collection of genetic resources for the breeding of Siberian apricot and related species. PMID:24516551

  4. High-level waste processing and disposal

    NASA Astrophysics Data System (ADS)

    Crandall, J. L.; Drause, H.; Sombret, C.; Uematsu, K.

    The national high level waste disposal plans for France, the Federal Republic of Germany, Japan, and the United States are covered. Three conclusions are reached. The first conclusion is that an excellent technology already exists for high level waste disposal. With appropriate packaging, spent fuel seems to be an acceptable waste form. Borosilicate glass reprocessing waste forms are well understood, in production in France, and scheduled for production in the next few years in a number of other countries. For final disposal, a number of candidate geological repository sites have been identified and several demonstration sites opened. The second conclusion is that adequate financing and a legal basis for waste disposal are in place in most countries. Costs of high level waste disposal will probably and about 5 to 10% to the costs of nuclear electric power. Third conclusion is less optimistic.

  5. Alumina as a Thermoluminescent Material

    SciTech Connect

    Uzun, Erdem; Yarar, Yasemin

    2007-04-23

    Thermoluminescence dosimeters are extensively used for quantitative dose measurements in various irradiation fields. They are also important for environmental monitoring after nuclear accident and weapon tests. In this work, the principles of TLD dosimeter and characteristics of several TLD materials are presented. Besides, taken into account the importance as a raw material, the utilization of domestic alumina (Al2O3) in TLDs as a thermoluminescent material is discussed.

  6. High-level-waste immobilization

    SciTech Connect

    Crandall, J L

    1982-01-01

    Analysis of risks, environmental effects, process feasibility, and costs for disposal of immobilized high-level wastes in geologic repositories indicates that the disposal system safety has a low sensitivity to the choice of the waste disposal form.

  7. International High Level Nuclear Waste Management

    ERIC Educational Resources Information Center

    Dreschhoff, Gisela; And Others

    1974-01-01

    Discusses the radioactive waste management in Belgium, Canada, France, Germany, India, Italy, Japan, the United Kingdom, the United States, and the USSR. Indicates that scientists and statesmen should look beyond their own lifetimes into future centuries and millennia to conduct long-range plans essential to protection of future generations. (CC)

  8. Melt processed crystalline ceramic waste forms for advanced nuclear fuel cycles: CRP T21027 1813: Processing technologies for high level waste, formulation of matrices and characterization of waste forms, task 17208: Final report

    SciTech Connect

    Amoroso, J. W.; Marra, J. C.

    2015-08-26

    A multi-phase ceramic waste form is being developed at the Savannah River National Laboratory (SRNL) for treatment of secondary waste streams generated by reprocessing commercial spent nuclear. The envisioned waste stream contains a mixture of transition, alkali, alkaline earth, and lanthanide metals. Ceramic waste forms are tailored (engineered) to incorporate waste components as part of their crystal structure based on knowledge from naturally found minerals containing radioactive and non-radioactive species similar to the radionuclides of concern in wastes from fuel reprocessing. The ability to tailor ceramics to mimic naturally occurring crystals substantiates the long term stability of such crystals (ceramics) over geologic timescales of interest for nuclear waste immobilization [1]. A durable multi-phase ceramic waste form tailored to incorporate all the waste components has the potential to broaden the available disposal options and thus minimize the storage and disposal costs associated with aqueous reprocessing. This report summarizes results from three years of work on the IAEA Coordinated Research Project on “Processing technologies for high level waste, formulation of matrices and characterization of waste forms” (T21027), and specific task “Melt Processed Crystalline Ceramic Waste Forms for Advanced Nuclear Fuel Cycles” (17208).

  9. Melt processed crystalline ceramic waste forms for advanced nuclear fuel cycles: CRP T21027 1813: Processing technologies for high level waste, formulation of matrices and characterization of waste forms, Task 17208: Final report

    SciTech Connect

    Amoroso, J. W.; Marra, J. C.

    2015-08-26

    A multi-phase ceramic waste form is being developed at the Savannah River National Laboratory (SRNL) for treatment of secondary waste streams generated by reprocessing commercial spent nuclear. The envisioned waste stream contains a mixture of transition, alkali, alkaline earth, and lanthanide metals. Ceramic waste forms are tailored (engineered) to incorporate waste components as part of their crystal structure based on knowledge from naturally found minerals containing radioactive and non-radioactive species similar to the radionuclides of concern in wastes from fuel reprocessing. The ability to tailor ceramics to mimic naturally occurring crystals substantiates the long term stability of such crystals (ceramics) over geologic timescales of interest for nuclear waste immobilization [1]. A durable multi-phase ceramic waste form tailored to incorporate all the waste components has the potential to broaden the available disposal options and thus minimize the storage and disposal costs associated with aqueous reprocessing. This report summarizes results from three years of work on the IAEA Coordinated Research Project on “Processing technologies for high level waste, formulation of matrices and characterization of waste forms” (T21027), and specific task “Melt Processed Crystalline Ceramic Waste Forms for Advanced Nuclear Fuel Cycles” (17208).

  10. Investigations of natural groundwater hazards at the proposed Yucca Mountain high level nuclear waste repository. Part A: Geology at Yucca Mountain. Part B: Modeling of hydro-tectonic phenomena relevant to Yucca Mountain. Annual report - Nevada

    SciTech Connect

    Szymanski, J.S.; Schluter, C.M.; Livingston, D.E.

    1993-05-01

    This document is an annual report describing investigations of natural groundwater hazards at the proposed Yucca Mountain, Nevada High-Level Nuclear Waste Repository.This document describes research studies of the origin of near surface calcite/silica deposits at Yucca Mountain. The origin of these deposits is controversial and the authors have extended and strengthened the basis of their arguments for epigenetic, metasomatic alteration of the tuffs at Yucca Mountain. This report includes stratigraphic, mineralogical, and geochronological information along with geochemical data to support the conclusions described by Livingston and Szymanski, and others. As part of their first annual report, they take this opportunity to clarify the technical basis of their concerns and summarize the critical geological field evidence and related information. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.

  11. Proposed methodology for completion of scenario analysis for the Basalt Waste Isolation Project. [Assessment of post-closure performance for a proposed repository for high-level nuclear waste

    SciTech Connect

    Roberds, W.J.; Plum, R.J.; Visca, P.J.

    1984-11-01

    This report presents the methodology to complete an assessment of postclosure performance, considering all credible scenarios, including the nominal case, for a proposed repository for high-level nuclear waste at the Hanford Site, Washington State. The methodology consists of defensible techniques for identifying and screening scenarios, and for then assessing the risks associated with each. The results of the scenario analysis are used to comprehensively determine system performance and/or risk for evaluation of compliance with postclosure performance criteria (10 CFR 60 and 40 CFR 191). In addition to describing the proposed methodology, this report reviews available methodologies for scenario analysis, discusses pertinent performance assessment and uncertainty concepts, advises how to implement the methodology (including the organizational requirements and a description of tasks) and recommends how to use the methodology in guiding future site characterization, analysis, and engineered subsystem design work. 36 refs., 24 figs., 1 tab.

  12. Bauxite and alumina

    USGS Publications Warehouse

    Bray, E.L.

    2009-01-01

    The article provides information on bauxite and alumina mining. U.S. states like Alabama, Arkansas and Georgia produced small amounts of bauxite and bauxitic clays for nonmetallurgical uses. Total metallurgical-grade bauxite imports in 2008 is cited. The leading suppliers of bauxite to the U.S. are Jamaica, Guinea and Brazil. The estimated domestic production of alumina in 2008 is mentioned. It also discusses consumption and prices of both bauxite and alumina.

  13. Porous Alumina Films with Width-Controllable Alumina Stripes

    PubMed Central

    2010-01-01

    Porous alumina films had been fabricated by anodizing from aluminum films after an electropolishing procedure. Alumina stripes without pores can be distinguished on the surface of the porous alumina films. The width of the alumina stripes increases proportionally with the anodizing voltage. And the pores tend to be initiated close to the alumina stripes. These phenomena can be ascribed to the electric field distribution in the alumina barrier layer caused by the geometric structure of the aluminum surface. PMID:21170406

  14. Porous Alumina Films with Width-Controllable Alumina Stripes.

    PubMed

    Huang, Kai; Huang, Shi-Ming; Pu, Lin; Shi, Yi; Wu, Zhi-Ming; Ji, Li; Kang, Jun-Yong

    2010-01-01

    Porous alumina films had been fabricated by anodizing from aluminum films after an electropolishing procedure. Alumina stripes without pores can be distinguished on the surface of the porous alumina films. The width of the alumina stripes increases proportionally with the anodizing voltage. And the pores tend to be initiated close to the alumina stripes. These phenomena can be ascribed to the electric field distribution in the alumina barrier layer caused by the geometric structure of the aluminum surface. PMID:21170406

  15. Porous Alumina Films with Width-Controllable Alumina Stripes

    NASA Astrophysics Data System (ADS)

    Huang, Kai; Huang, Shi-Ming; Pu, Lin; Shi, Yi; Wu, Zhi-Ming; Ji, Li; Kang, Jun-Yong

    2010-12-01

    Porous alumina films had been fabricated by anodizing from aluminum films after an electropolishing procedure. Alumina stripes without pores can be distinguished on the surface of the porous alumina films. The width of the alumina stripes increases proportionally with the anodizing voltage. And the pores tend to be initiated close to the alumina stripes. These phenomena can be ascribed to the electric field distribution in the alumina barrier layer caused by the geometric structure of the aluminum surface.

  16. High-Level Radioactive Waste.

    ERIC Educational Resources Information Center

    Hayden, Howard C.

    1995-01-01

    Presents a method to calculate the amount of high-level radioactive waste by taking into consideration the following factors: the fission process that yields the waste, identification of the waste, the energy required to run a 1-GWe plant for one year, and the uranium mass required to produce that energy. Briefly discusses waste disposal and…

  17. Microporous alumina ceramic membranes

    DOEpatents

    Anderson, M.A.; Guangyao Sheng.

    1993-05-04

    Several methods are disclosed for the preparation microporous alumina ceramic membranes. For the first time, porous alumina membranes are made which have mean pore sizes less than 100 Angstroms and substantially no pores larger than that size. The methods are based on improved sol-gel techniques.

  18. Microporous alumina ceramic membranes

    DOEpatents

    Anderson, Marc A.; Sheng, Guangyao

    1993-01-01

    Several methods are disclosed for the preparation microporous alumina ceramic membranes. For the first time, porous alumina membranes are made which have mean pore sizes less than 100 Angstroms and substantially no pores larger than that size. The methods are based on improved sol-gel techniques.

  19. High-level waste qualification: Managing uncertainty

    SciTech Connect

    Pulsipher, B.A.

    1993-09-01

    A vitrification facility is being developed by the U.S. Department of Energy (DOE) at the West Valley Demonstration Plant (WVDP) near Buffalo, New York, where approximately 300 canisters of high-level nuclear waste glass will be produced. To assure that the produced waste form is acceptable, uncertainty must be managed. Statistical issues arise due to sampling, waste variations, processing uncertainties, and analytical variations. This paper presents elements of a strategy to characterize and manage the uncertainties associated with demonstrating that an acceptable waste form product is achieved. Specific examples are provided within the context of statistical work performed by Pacific Northwest Laboratory (PNL).

  20. A methodology to constrain the parameters of a hydrogeological discrete fracture network model for sparsely fractured crystalline rock, exemplified by data from the proposed high-level nuclear waste repository site at Forsmark, Sweden

    NASA Astrophysics Data System (ADS)

    Follin, Sven; Hartley, Lee; Rhén, Ingvar; Jackson, Peter; Joyce, Steven; Roberts, David; Swift, Ben

    2014-03-01

    The large-scale geological structure of the crystalline rock at the proposed high-level nuclear waste repository site at Forsmark, Sweden, has been classified in terms of deformation zones of elevated fracture frequency. The rock between deformation zones was divided into fracture domains according to fracture frequency. A methodology to constrain the geometric and hydraulic parameters that define a discrete fracture network (DFN) model for each fracture domain is presented. The methodology is based on flow logging and down-hole imaging in cored boreholes in combination with DFN realizations, fracture connectivity analysis and pumping test simulations. The simulations suggest that a good match could be obtained for a power law size distribution where the value of the location parameter equals the borehole radius but with different values for the shape parameter, depending on fracture domain and fracture set. Fractures around 10-100 m in size are the ones that typically form the connected network, giving inflows in the simulations. The report also addresses the issue of up-scaling of DFN properties to equivalent continuous porous medium (ECPM) bulk flow properties. Comparisons with double-packer injection tests provide confidence that the derived DFN formulation of detailed flows within individual fractures is also suited to simulating mean bulk flow properties and their spatial variability.

  1. Approaches to confirmatory testing of a groundwater flow model for sparsely fractured crystalline rock, exemplified by data from the proposed high-level nuclear waste repository site at Forsmark, Sweden

    NASA Astrophysics Data System (ADS)

    Follin, Sven; Hartley, Lee

    2014-03-01

    The Svensk Kärnbränslehantering AB (SKB) has proposed the Forsmark site as a future repository for spent high-level nuclear fuel, involving disposal at about 470 m depth in sparsely fractured crystalline bedrock. An essential part of the completed inter-disciplinary site investigation was to develop an integrated account of the site and its regional setting, including the current state of the geosphere and the biosphere as well as natural processes affecting long-term evolution. First, this report recollects the integrated understanding and some key hydraulic characteristics of the crystalline bedrock at Forsmark along with a description of the flow model set-up and the methodology used for paleoclimatic flow modeling. Second, the protocol used for site-scale groundwater flow and solute transport modeling is demonstrated. In order to conduct a quantitative assessment of groundwater flow paths at Forsmark, the standard guide for groundwater flow modeling was elaborated on, to support both discrete and porous media flow approaches. In total, four independent types of data were used to confirm that the final groundwater flow model for the crystalline bedrock was representative of site conditions.

  2. A transmissivity model for deformation zones in fractured crystalline rock and its possible correlation to in situ stress at the proposed high-level nuclear waste repository site at Forsmark, Sweden

    NASA Astrophysics Data System (ADS)

    Follin, Sven; Stigsson, Martin

    2014-03-01

    The Forsmark site was recently proposed by the Svensk Kärnbränslehantering AB (SKB) to serve as the potential site for construction of a future geological repository for spent high-level nuclear fuel at about 470 m depth in fractured crystalline rock. The considerations included, among other things, distance from regionally significant deformation zones with highly strained rock, lithological homogeneity, low hydraulic conductivity, groundwater salinity with an acceptable range, and lack of potential mineral resources. This report describes the calculation of transmissivity of deduced deformation zones at Forsmark and the transmissivity model used in the regional groundwater flow modeling carried out in support of the integrated site description. Besides significant decrease with increasing depth (more than four orders of magnitude over a depth of about 1 km), the calculated transmissivity values also reveal considerable spatial variability along the strikes of the zones, i.e. lateral heterogeneity (more than two orders of magnitude). A hydro-mechanical coupling is discussed, based on presented models for the tectonic evolution and the principal stress tensor. Tentatively, laboratory-scale relationships developed from normal stress experiments on a single fracture in crystalline rock can be used to estimate the maximum values of transmissivity of deduced deformation zones at Forsmark.

  3. Reuse of activated alumina

    SciTech Connect

    Hobensack, J.E.

    1991-12-31

    Activated alumina is used as a trapping media to remove trace quantities of UF{sub 6} from process vent streams. The current uranium recovery method employs concentrated nitric acid which destroys the alumina pellets and forms a sludge which is a storage and disposal problem. A recently developed technique using a distilled water rinse followed by three dilute acid rinses removes on average 97% of the uranium, and leaves the pellets intact with crush strength and surface area values comparable with new material. Trapping tests confirm the effectiveness of the recycled alumina as UF{sub 6} trapping media.

  4. The CMS high level trigger

    NASA Astrophysics Data System (ADS)

    Gori, Valentina

    2014-05-01

    The CMS experiment has been designed with a 2-level trigger system: the Level 1 Trigger, implemented on custom-designed electronics, and the High Level Trigger (HLT), a streamlined version of the CMS offline reconstruction software running on a computer farm. A software trigger system requires a tradeoff between the complexity of the algorithms running on the available computing power, the sustainable output rate, and the selection efficiency. Here we will present the performance of the main triggers used during the 2012 data taking, ranging from simpler single-object selections to more complex algorithms combining different objects, and applying analysis-level reconstruction and selection. We will discuss the optimisation of the triggers and the specific techniques to cope with the increasing LHC pile-up, reducing its impact on the physics performance.

  5. The CMS High Level Trigger

    NASA Astrophysics Data System (ADS)

    Trocino, Daniele

    2014-06-01

    The CMS experiment has been designed with a two-level trigger system: the Level-1 Trigger, implemented in custom-designed electronics, and the High-Level Trigger (HLT), a streamlined version of the CMS offline reconstruction software running on a computer farm. A software trigger system requires a tradeoff between the complexity of the algorithms running with the available computing power, the sustainable output rate, and the selection efficiency. We present the performance of the main triggers used during the 2012 data taking, ranging from simple single-object selections to more complex algorithms combining different objects, and applying analysis-level reconstruction and selection. We discuss the optimisation of the trigger and the specific techniques to cope with the increasing LHC pile-up, reducing its impact on the physics performance.

  6. Alumina from oil shale

    SciTech Connect

    Smith, J.W.

    1980-01-01

    Dawsonite-bearing oil shale of Colorado's Green River Formation offers a unique and vast (6.5 billion tons of Al/sub 2/O/sub 3/) resource of easily extractable alumina. The processing methods required by the thermal reactions of dawsonite and its oil-shale carrier also require production of shale oil, soda ash, and nahcolite as marketable coproducts. These production methods are presented. The alumina production process is contrasted with the Bayer process to describe technical advantages of extraction of alumina from oil shale which may offset the problems associated with processing a relatively lean ore. While alumina production from oil shale requires development of new technology, the technical problems appear solvable. Only the political problems arising from the now onerous and completely unnecessary Federal oil-shale withdrawal appear less solvable.

  7. Paleostress evolution through 1.7 Gyr of geological history - Brittle deformation of the Olkiluoto Island, SW Finland, and implications on the characterisation of a high-level nuclear waste repository

    NASA Astrophysics Data System (ADS)

    Mattila, Jussi; Viola, Giulio; Zwingmann, Horst

    2013-04-01

    Olkiluoto Island, located in SW Finland, is being evaluated as the potential final repository for the high-level nuclear waste generated in Finland, and the repository is expected to become operational in A.D. 2020. The bedrock at Olkiluoto is formed by the crystalline basement of the Fennoscandian Shield and consists of Proterozoic amphibolite-facies metasedimentary rocks and gneisses. During feasibility studies for deep geological repositories for high-level nuclear waste, it is essential to characterise in detail potential fluid flow pathways and structures prone to movements during the repository life span. In crystalline geological settings these consist mainly of existing brittle structures. As a part of these studies at Olkiluoto Island, we documented in detail the character and kinematics of the fault zones of the site and developed a conceptual model of the brittle deformational history of the region by using a unique fault-slip data set consisting of more than 2000 striated faults, collected from both drill cores and the walls of an investigation tunnel reaching to the depth of 420 meters. By applying iterative inversion procedures on the fault-slip data, combined with the investigation of the regional brittle structures through the analysis of key outcrops, it was possible to generate distinct paleostress tensors and to define specific tectonic events at the site. The results were strengthened by comparing the output with the known paleostress states of southern Scandinavia and by using absolute and relative time criteria. Uniaxial compression of presumably late Svecofennian age with a regional NNW- SSE ?1 axis was active soon after 1.75 Ga ago, when brittle deformation was first accommodated in the region. A younger transpressive paleostress field with a NE-SW ?1 axis caused reactivation of some of the structures formed during the first shortening event. A phase of ESE-WNW extension is constrained by a number of tensors and direct field evidence and is

  8. Bauxite and alumina

    USGS Publications Warehouse

    Bray, E.L.

    2011-01-01

    The article discusses the latest developments in the bauxite and alumina industry, particularly in the U.S., as of June 2011. It claims that the U.S. mainly relies on imports for its bauxite consumption. Several states, including Alabama, Arkansas and Georgia, however, produce small amounts of bauxite and bauxitic clays for nonmetallurgical purposes. The major exporters of alumina to the U.S. include Australia, Brazil and Jamaica.

  9. Alumina fiber strength improvement

    NASA Technical Reports Server (NTRS)

    Pepper, R. T.; Nelson, D. C.

    1982-01-01

    The effective fiber strength of alumina fibers in an aluminum composite was increased to 173,000 psi. A high temperature heat treatment, combined with a glassy carbon surface coating, was used to prevent degradation and improve fiber tensile strength. Attempts to achieve chemical strengthening of the alumina fiber by chromium oxide and boron oxide coatings proved unsuccessful. A major problem encountered on the program was the low and inconsistent strength of the Dupont Fiber FP used for the investigation.

  10. Characterization of vitrified ICPP alumina waste calcine

    SciTech Connect

    Cole, H.S.; Brotzman, J.R.; Simpson, G.G.

    1980-08-01

    The properties of one borosilicate and two borophosphate glasses previously developed to vitrify an ICPP alumina nuclear waste calcine are determined. Based on melt viscosity at 1100/sup 0/C and leach rate, the maximum permissible calcine contents in the borophosphate and borosilicate formulations are 26 and 16 mol%, respectively. Glasses containing lesser amounts of calcine do not develop crystalline compounds upon annealing. Based upon the same viscosity and leach rate criteria, 40 wt % CaO or zirconia calcine can be substituted for alumina calcine in the borophosphate glasses. Ten wt % of either additive can be substituted for alumina calcine in the borosilicate glass. Minor modifications of the alkali or cupric oxide content in the borophosphate glasses does not alter glass characteristics.

  11. Large pore alumina

    SciTech Connect

    Ternan, M. )

    1994-04-01

    Earlier the authors reported preparation conditions for an alumina material which contained large diameter macropores (0.1-100 [mu]). The preparation variable that caused the formation of the uncommonly large macropores was the large acid/alumina ratios which were very much greater than the ones used in the preparation of conventional porous aluminas. The alumina material had large BET surface areas (200 m[sup 2]/g) and small mercury porosimetry surface areas (1 m[sup 2]/g). This indicated that micropores (d[sub MIP]<2 nm) were present in the alumina, since they were large enough for nitrogen gas molecules to enter, but too small for mercury to enter. As a result they would be too small for significant diffusion rates of residuum molecules. In earlier work, the calcining temperature was fixed at 500[degrees]C. In the current work, variations in both calcining temperature and calcining time were used in an attempt to convert some of the micropores into mesopores. 12 refs., 2 figs., 1 tab.

  12. Reference commercial high-level waste glass and canister definition.

    SciTech Connect

    Slate, S.C.; Ross, W.A.; Partain, W.L.

    1981-09-01

    This report presents technical data and performance characteristics of a high-level waste glass and canister intended for use in the design of a complete waste encapsulation package suitable for disposal in a geologic repository. The borosilicate glass contained in the stainless steel canister represents the probable type of high-level waste product that will be produced in a commercial nuclear-fuel reprocessing plant. Development history is summarized for high-level liquid waste compositions, waste glass composition and characteristics, and canister design. The decay histories of the fission products and actinides (plus daughters) calculated by the ORIGEN-II code are presented.

  13. High-level waste program progress report, April 1, 1980-June 30, 1980

    SciTech Connect

    1980-08-01

    The highlights of this report are on: waste management analysis for nuclear fuel cycles; fixation of waste in concrete; study of ceramic and cermet waste forms; alternative high-level waste forms development; and high-level waste container development.

  14. Alumina Technology Roadmap

    SciTech Connect

    none,

    2002-02-01

    The Alumina Technology Roadmap outlines a comprehensive long-term research and development plan that defines the industry's collective future and establishes a clear pathway forward. It emphasizes twelve high-priority R&D areas deemed most significant in addressing the strategic goals.

  15. Bauxite and alumina

    USGS Publications Warehouse

    Bray, E.L.

    2010-01-01

    The article reports on the global market performance of bauxite and alumina in 2009 and presents an outlook for their 2010 performance. There were only several U.S. states that could produce bauxite and bauxitic clays including Georgia, Arkansas, and Alabama. The prices for imported refractory-grade calcined bauxite ranged between 426 U.S. dollars and 554 dollars per ton.

  16. Prediction of alumina penetration

    SciTech Connect

    Mandell, D A

    1993-02-01

    The MESA hydrocode was used to predict two-dimensional tests of L/D 10 and L/D 15 tungsten rods impacting AD 90 alumina with a steel backing. The residual penetration into the steel is the measured quantity in these experiments conducted at the Southwest Research Institute (SWR). The interface velocity as a function of time between an alumina target and a lithium fluoride window, impacted by an alumina disk at velocities between 544 m/s and 2329 m/s, was also predicted. These one-dimensional flyer plate experiments were conducted at Sandia National Laboratories using Coors AD 995 alumina. The material strength and fracture models are important in the prediction of ceramic experiments. The models used in these predictions are discussed. The penetrations in the two-dimensional tests were predicted to 11.4 percent or better. In five of the six experiments, the predicted penetration depth was deeper than the measured value. This trend is expected since the calculation is based on ideal conditions. The results show that good agreement between the 1-D flyer plate data and the MESA predictions exists at the lower impact velocities, but the maximum velocity is overpredicted as the flyer plate velocity increases. At a flyer plate velocity of 2329 m/s the code overpredicted the data by 12.3 percent.

  17. Solid Lubricant For Alumina

    NASA Technical Reports Server (NTRS)

    Dellacorte, Christopher; Pepper, Stephen V.; Honecy, Frank S.

    1993-01-01

    Outer layer of silver lubricates, while intermediate layer of titanium ensures adhesion. Lubricating outer films of silver deposited on thin intermediate films of titanium on alumina substrates found to reduce sliding friction and wear. Films provide effective lubrication for ceramic seals, bearings, and other hot sliding components in advanced high-temperature engines.

  18. An investigation of the impact of conceptual model uncertainty on the estimated performance of a hypothetical high-level nuclear waste repository site in unsaturated, fractured tuff; Yucca Mountain Site Characterization Project

    SciTech Connect

    Gallegos, D.P.; Phol, P.I.; Updegraff, C.D.

    1992-04-01

    Performance assessment modeling for High Level Waste (HLW) disposal incorporates three different types of uncertainty. These include data and parameter uncertainty, modeling uncertainty (which includes conceptual, mathematical, and numerical), and uncertainty associated with predicting the future state of the system. In this study, the potential impact of conceptual model uncertainty on the estimated performance of a hypothetical high-level radioactive waste disposal site in unsaturated, fractured tuff has been assessed for a given group of conceptual models. This was accomplished by taking a series of six, one-dimensional conceptual models, which differed only by the fundamental assumptions used to develop them, and conducting ground-water flow and radionuclide transport simulations. Complementary cumulative distribution functions (CCDFs) representing integrated radionuclide release to the water table indicate that differences in the basic assumptions used to develop conceptual models can have a significant impact on the estimated performance of the site. Because each of the conceptual models employed the same mathematical and numerical models, contained the same data and parameter values and ranges, and did not consider the possible future states of the system, changes in the CCDF could be attributed primarily to differences in conceptual modeling assumptions. Studies such as this one could help prioritize site characterization activities by identifying critical and uncertain assumptions used in model development, thereby providing guidance as to where reduction of uncertainty is most important.

  19. High Temperature Stability of Potassium Beta Alumina

    NASA Technical Reports Server (NTRS)

    Williams, R. M.; Kisor, A.; Ryan, M. A.

    1996-01-01

    None. From Objectives section: Evaluate the stability of potassium beta alumina under potassium AMTEC operating conditions. Evaluate the stability regime in which potassium beta alumina can be fabricated.

  20. Alumina reduction cell

    SciTech Connect

    Tabereaux, A.T.; Gunnip, F.L.

    1987-06-16

    An alumina reduction cell is described having a cathode and an anode. The anode is formed of a carbonaceous paste and baked during operation of cell and the anode having rows of anode pins on opposing faces. The pins are positioned by passing the pins through openings in anode channels vertically stacked along the opposing faces of the anode. The lowermost row of anode pins carries current through the anode; the improvement positions the anode pins passing through along a line of constant current distribution in the anode.

  1. Bauxite Mining and Alumina Refining

    PubMed Central

    Frisch, Neale; Olney, David

    2014-01-01

    Objective: To describe bauxite mining and alumina refining processes and to outline the relevant physical, chemical, biological, ergonomic, and psychosocial health risks. Methods: Review article. Results: The most important risks relate to noise, ergonomics, trauma, and caustic soda splashes of the skin/eyes. Other risks of note relate to fatigue, heat, and solar ultraviolet and for some operations tropical diseases, venomous/dangerous animals, and remote locations. Exposures to bauxite dust, alumina dust, and caustic mist in contemporary best-practice bauxite mining and alumina refining operations have not been demonstrated to be associated with clinically significant decrements in lung function. Exposures to bauxite dust and alumina dust at such operations are also not associated with the incidence of cancer. Conclusions: A range of occupational health risks in bauxite mining and alumina refining require the maintenance of effective control measures. PMID:24806720

  2. Tip-like anodic alumina

    NASA Astrophysics Data System (ADS)

    Sun, Q. W.; Ding, G. Q.; Li, Y. B.; Zheng, M. J.; Shen, W. Z.

    2007-05-01

    Porous anodic alumina membranes and various nanotips have been demonstrating individually their unique usefulness in current nanotechnology. We present a one-step electrochemical approach to fabricate nanoscale alumina tips (tip-like anodic alumina, TAA) in order to combine the benefits of porous anodic alumina and a nanoscale tip array. The realized TAA has an ordered tip surface with controllable aspect ratio and high sheet density of ~1011 cm-2. The formation of alumina nanotips is due to the heat-driven dissolution of the nanopore surface. We have further shown that the surface nanostructure in TAA leads to the wettability reversal, and preferred nucleation and growth during material deposition. The easy and large-scale fabrication of TAA makes it possible for novel nanodevice applications.

  3. Branchy alumina nanotubes

    NASA Astrophysics Data System (ADS)

    Zou, Jianping; Pu, Lin; Bao, Ximao; Feng, Duan

    2002-02-01

    Branchy alumina nanotubes (bANTs) have been shown to exist in aluminum oxide. Electron-beam evaporated 400 nm Al film on Si substrate is stepwise anodized in dilute sulfuric acid under the constant dc voltage 40 V at 10.0 °C. This electrochemical-anodizing route resulted in the formation of individual bANTs. Transmission electron microscopy showed that the length of the bANTs was around 450 nm, and the inner diameter was around 10-20 nm. We deduced that the bANTs, the completely detached multibranchy cells of anodic porous alumina (APA) film, should be evolved from the stagnant cells of the APA mother film. The bANTs may be used as templates in fabrication of individual branchy nanoscale cables, jacks, and heterojunctions. The proposed formation mechanisms of the bANTs and the stagnant cells should give some insights into the long-standing problem of APA film, i.e., the self-ordering mechanism of the cells arrangement in porous anodization of aluminum.

  4. [Corrosion testing of high level radioactive waste. Final report

    SciTech Connect

    1996-06-01

    Alloys under consideration as candidates for the high level nuclear waste containers at Yucca Mountain were exposed to a range of corrosion conditions and their performance measured. The alloys tested were Incoloy 825, 70/30 Copper-Nickel, Monel 400, Hastelloy C- 22, and low carbon steel. The test conditions varied were: temperature, concentration, agitation, and crevice simulation. Only in the case of carbon steel was significant attack noted. This attack appeared to be transport limited.

  5. Overview of high-level waste management accomplishments

    SciTech Connect

    Lawroski, H; Berreth, J R; Freeby, W A

    1980-01-01

    Storage of power reactor spent fuel is necessary at present because of the lack of reprocessing operations particularly in the U.S. By considering the above solidification and storage scenario, there is more than reasonable assurance that acceptable, stable, low heat generation rate, solidified waste can be produced, and safely disposed. The public perception of no waste disposal solutions is being exploited by detractors of nuclear power application. The inability to even point to one overall system demonstration lends credibility to the negative assertions. By delaying the gathering of on-line information to qualify repository sites, and to implement a demonstration, the actions of the nuclear power detractors are self serving in that they can continue to point out there is no demonstration of satisfactory high-level waste disposal. By maintaining the liquid and solidified high-level waste in secure above ground storage until acceptable decay heat generation rates are achieved, by producing a compatible, high integrity, solid waste form, by providing a second or even third barrier as a compound container and by inserting the enclosed waste form in a qualified repository with spacing to assure moderately low temperature disposal conditions, there appears to be no technical reason for not progressing further with the disposal of high-level wastes and needed implementation of the complete nuclear power fuel cycle.

  6. Spent fuel and high-level radioactive waste transportation report

    SciTech Connect

    Not Available

    1989-11-01

    This publication is intended to provide its readers with an introduction to the issues surrounding the subject of transportation of spent nuclear fuel and high-level radioactive waste, especially as those issues impact the southern region of the United States. It was originally issued by the Southern States Energy Board (SSEB) in July 1987 as the Spent Nuclear Fuel and High-Level Radioactive Waste Transportation Primer, a document patterned on work performed by the Western Interstate Energy Board and designed as a ``comprehensive overview of the issues.`` This work differs from that earlier effort in that it is designed for the educated layman with little or no background in nuclear waste issues. In addition, this document is not a comprehensive examination of nuclear waste issues but should instead serve as a general introduction to the subject. Owing to changes in the nuclear waste management system, program activities by the US Department of Energy and other federal agencies and developing technologies, much of this information is dated quickly. While this report uses the most recent data available, readers should keep in mind that some of the material is subject to rapid change. SSEB plans periodic updates in the future to account for changes in the program. Replacement pages sew be supplied to all parties in receipt of this publication provided they remain on the SSEB mailing list.

  7. Spent fuel and high-level radioactive waste transportation report

    SciTech Connect

    Not Available

    1990-11-01

    This publication is intended to provide its readers with an introduction to the issues surrounding the subject of transportation of spent nuclear fuel and high-level radioactive waste, especially as those issues impact the southern region of the United States. It was originally issued by the Southern States Energy Board (SSEB) in July 1987 as the Spent Nuclear Fuel and High-Level Radioactive Waste Transportation Primer, a document patterned on work performed by the Western Interstate Energy Board and designed as a ``comprehensive overview of the issues.`` This work differs from that earlier effort in that it is designed for the educated layman with little or no background in nuclear waste issues. In addition, this document is not a comprehensive examination of nuclear waste issues but should instead serve as a general introduction to the subject. Owing to changes in the nuclear waste management system, program activities by the US Department of Energy and other federal agencies and developing technologies, much of this information is dated quickly. While this report uses the most recent data available, readers should keep in mind that some of the material is subject to rapid change. SSEB plans periodic updates in the future to account for changes in the program. Replacement pages will be supplied to all parties in receipt of this publication provided they remain on the SSEB mailing list.

  8. Spent Fuel and High-Level Radioactive Waste Transportation Report

    SciTech Connect

    Not Available

    1992-03-01

    This publication is intended to provide its readers with an introduction to the issues surrounding the subject of transportation of spent nuclear fuel and high-level radioactive waste, especially as those issues impact the southern region of the United States. It was originally issued by SSEB in July 1987 as the Spent Nuclear Fuel and High-Level Radioactive Waste Transportation Primer, a document patterned on work performed by the Western Interstate Energy Board and designed as a ``comprehensive overview of the issues.`` This work differs from that earlier effort in that it is designed for the educated layman with little or no background in nuclear waste Issues. In addition. this document is not a comprehensive examination of nuclear waste issues but should instead serve as a general introduction to the subject. Owing to changes in the nuclear waste management system, program activities by the US Department of Energy and other federal agencies and developing technologies, much of this information is dated quickly. While this report uses the most recent data available, readers should keep in mind that some of the material is subject to rapid change. SSEB plans periodic updates in the future to account for changes in the program. Replacement pages will be supplied to all parties in receipt of this publication provided they remain on the SSEB mailing list.

  9. High-Level Genetic Diversity but No Population Structure Inferred from Nuclear and Mitochondrial Markers of the Peritrichous Ciliate Carchesium polypinum in the Grand River Basin (North America)▿ †

    PubMed Central

    Gentekaki, E.; Lynn, D. H.

    2009-01-01

    Studies that assess intraspecific genetic variation in ciliates are few and quite recent. Consequently, knowledge of the subject and understanding of the processes that underlie it are limited. We sought to assess the degree of intraspecific genetic variation in Carchesium polypinum (Ciliophora: Peritrichia), a cosmopolitan, freshwater ciliate. We isolated colonies of C. polypinum from locations in the Grand River basin in Southwestern Ontario, Canada. We then used the nuclear markers—ITS1, ITS2, and the hypervariable regions of the large subunit rRNA—and an 819-bp fragment of the mitochondrial cytochrome c oxidase I gene (cox-1) to investigate the intraspecific genetic variation of C. polypinum and the degree of resolution of the above-mentioned markers at the population level. We also sought to determine whether the organism demonstrated any population structure that mapped onto the geography of the region. Our study shows that there is a high degree of genetic diversity at the isolate level, revealed by the mitochondrial markers but not the nuclear markers. Furthermore, our results indicate that C. polypinum is likely not a single morphospecies as previously thought. PMID:19304815

  10. Gelcasting Polycrystalline Alumina

    SciTech Connect

    Janney, M.A.; Zuk, K.J.; Wei, G.C.

    2000-01-01

    OSRAM SYLVANIA INC. is a major U.S. manufacturer of high-intensity lighting. Among its products is the Lumalux TM line of high-pressure sodium vapor arc lamps, which are used for industrial, highway, and street lighting. The key to the performance of these lamps is the polycrystalline alumina (PCA) tube that is used to contain the plasma that is formed in the electric arc. That plasma consists of ionized sodium, mercury, and xenon vapors. The key attributes of the PCA tubes are their transparency ({approximately}97% total transmittance in the visible), their refractoriness (inner wall temperature can reach l2OOC), and their chemical resistance (sodium and mercury vapor are extremely corrosive). The current efficiency of the lamps is very high, up to 100 initial lumens per watt. (Compare incandescent lamps 10-20 lumens per watt, fluorescent lamps 25-90 lumens per watt.)

  11. A Software Architecture for High Level Applications

    SciTech Connect

    Shen,G.

    2009-05-04

    A modular software platform for high level applications is under development at the National Synchrotron Light Source II project. This platform is based on client-server architecture, and the components of high level applications on this platform will be modular and distributed, and therefore reusable. An online model server is indispensable for model based control. Different accelerator facilities have different requirements for the online simulation. To supply various accelerator simulators, a set of narrow and general application programming interfaces is developed based on Tracy-3 and Elegant. This paper describes the system architecture for the modular high level applications, the design of narrow and general application programming interface for an online model server, and the prototype of online model server.

  12. High-Level Application Framework for LCLS

    SciTech Connect

    Chu, P; Chevtsov, S.; Fairley, D.; Larrieu, C.; Rock, J.; Rogind, D.; White, G.; Zalazny, M.; /SLAC

    2008-04-22

    A framework for high level accelerator application software is being developed for the Linac Coherent Light Source (LCLS). The framework is based on plug-in technology developed by an open source project, Eclipse. Many existing functionalities provided by Eclipse are available to high-level applications written within this framework. The framework also contains static data storage configuration and dynamic data connectivity. Because the framework is Eclipse-based, it is highly compatible with any other Eclipse plug-ins. The entire infrastructure of the software framework will be presented. Planned applications and plug-ins based on the framework are also presented.

  13. A comparison of high-level waste form characteristics

    SciTech Connect

    Salmon, R.; Notz, K.J.

    1991-01-01

    There are currently about 1055 million curies of high-level waste with a thermal output of about 2950 kilowatts (KW) at four sites in the United States: West Valley Demonstration Project (WVDP), Savannah River Site (SRS), Hanford Site (HANF), and Idaho National Engineering Laboratory (INEL). These quantities are expected to increase to about 1200 million curies and 3570 kw by the end of year 2020. Under the Nuclear Waste Policy Act, this high-level waste must ultimately be disposed of in a geologic repository. Accordingly, canisters of high-level waste immobilized in borosilicate glass or glass-ceramic mixtures are to be produced at the four sites and stored there until a repository becomes available. Data on the estimated production schedules and on the physical, chemical, and radiological characteristics of the canisters of immobilized high-level waste have been collected in OCRWM's Waste Characteristics Data Base, including recent updates an revisions. Comparisons of some of these data for the four sites are presented in this report. 14 refs., 3 tabs.

  14. High-level radioactive wastes. Supplement 1

    SciTech Connect

    McLaren, L.H.

    1984-09-01

    This bibliography contains information on high-level radioactive wastes included in the Department of Energy's Energy Data Base from August 1982 through December 1983. These citations are to research reports, journal articles, books, patents, theses, and conference papers from worldwide sources. Five indexes, each preceded by a brief description, are provided: Corporate Author, Personal Author, Subject, Contract Number, and Report Number. 1452 citations.

  15. PAIRWISE BLENDING OF HIGH LEVEL WASTE (HLW)

    SciTech Connect

    CERTA, P.J.

    2006-02-22

    The primary objective of this study is to demonstrate a mission scenario that uses pairwise and incidental blending of high level waste (HLW) to reduce the total mass of HLW glass. Secondary objectives include understanding how recent refinements to the tank waste inventory and solubility assumptions affect the mass of HLW glass and how logistical constraints may affect the efficacy of HLW blending.

  16. Alumina-Reinforced Zirconia Composites

    NASA Technical Reports Server (NTRS)

    Choi, Sung R.; Bansal, Narottam P.

    2003-01-01

    Alumina-reinforced zirconia composites, used as electrolyte materials for solid oxide fuel cells, were fabricated by hot pressing 10 mol percent yttria-stabilized zirconia (10-YSZ) reinforced with two different forms of alumina particulates and platelets each containing 0 to 30 mol percent alumina. Major mechanical and physical properties of both particulate and platelet composites including flexure strength, fracture toughness, slow crack growth, elastic modulus, density, Vickers microhardness, thermal conductivity, and microstructures were determined as a function of alumina content either at 25 C or at both 25 and 1000 C. Flexure strength and fracture toughness at 1000 C were maximized with 30 particulate and 30 mol percent platelet composites, respectively, while resistance to slow crack growth at 1000 C in air was greater for 30 mol percent platelet composite than for 30 mol percent particulate composites.

  17. Gelcast zirconia-alumina composites

    SciTech Connect

    Omatete, O.O.; Bleier, A.; Westmoreland, C.G.; Young, A.C.

    1991-01-01

    Near net-shaped parts of zirconia-alumina composites have been successfully formed by gelcasting, a technique which utilizes in situ polymerization of acrylamide monomers. The high solids loading required for gelcasting ({approximately}50 vol %) was obtained by controlling the pH-dependent stability of the aqueous zirconia-alumina suspensions. A strong correspondence was found among the surface charges on the particles, colloidal stability, and the maximum solids loading. 14 refs., 3 figs., 2 tabs.

  18. Management of data quality of high level waste characterization

    SciTech Connect

    Winters, W.I., Westinghouse Hanford

    1996-06-12

    Over the past 10 years, the Hanford Site has been transitioning from nuclear materials production to Site cleanup operations. High-level waste characterization at the Hanford Site provides data to support present waste processing operations, tank safety programs, and future waste disposal programs. Quality elements in the high-level waste characterization program will be presented by following a sample through the data quality objective, sampling, laboratory analysis and data review process. Transition from production to cleanup has resulted in changes in quality systems and program; the changes, as well as other issues in these quality programs, will be described. Laboratory assessment through quality control and performance evaluation programs will be described, and data assessments in the laboratory and final reporting in the tank characterization reports will be discussed.

  19. Evaluation and selection of candidate high-level waste forms

    SciTech Connect

    Bernadzikowski, T. A.; Allender, J. S.; Butler, J. L.; Gordon, D. E.; Gould, Jr., T. H.; Stone, J. A.

    1982-03-01

    Seven candidate waste forms being developed under the direction of the Department of Energy's National High-Level Waste (HLW) Technology Program, were evaluated as potential media for the immobilization and geologic disposal of high-level nuclear wastes. The evaluation combined preliminary waste form evaluations conducted at DOE defense waste-sites and independent laboratories, peer review assessments, a product performance evaluation, and a processability analysis. Based on the combined results of these four inputs, two of the seven forms, borosilicate glass and a titanate based ceramic, SYNROC, were selected as the reference and alternative forms for continued development and evaluation in the National HLW Program. Both the glass and ceramic forms are viable candidates for use at each of the DOE defense waste-sites; they are also potential candidates for immobilization of commercial reprocessing wastes. This report describes the waste form screening process, and discusses each of the four major inputs considered in the selection of the two forms.

  20. High-Level Waste Melter Study Report

    SciTech Connect

    Perez Jr, Joseph M; Bickford, Dennis F; Day, Delbert E; Kim, Dong-Sang; Lambert, Steven L; Marra, Sharon L; Peeler, David K; Strachan, Denis M; Triplett, Mark B; Vienna, John D; Wittman, Richard S

    2001-07-13

    At the Hanford Site in Richland, Washington, the path to site cleanup involves vitrification of the majority of the wastes that currently reside in large underground tanks. A Joule-heated glass melter is the equipment of choice for vitrifying the high-level fraction of these wastes. Even though this technology has general national and international acceptance, opportunities may exist to improve or change the technology to reduce the enormous cost of accomplishing the mission of site cleanup. Consequently, the U.S. Department of Energy requested the staff of the Tanks Focus Area to review immobilization technologies, waste forms, and modifications to requirements for solidification of the high-level waste fraction at Hanford to determine what aspects could affect cost reductions with reasonable long-term risk. The results of this study are summarized in this report.

  1. GLASS FORMULATION DEVELOPMENT TO SUPPORT MELTER TESTING TO DEMONSTRATE ENHANCED HIGH LEVEL WASTE THROUGHPUT

    SciTech Connect

    Marra, J; David Peeler, D; Tommy Edwards, T; Kevin Fox, K; Amanda Youchak, A; James Gillam, J

    2007-08-17

    The U.S. Department of Energy (DOE) is currently processing high-level waste (HLW) through a Joule-heated melter (JHM) at the Savannah River Site (SRS) and plans to vitrify HLW and Low activity waste (LAW) at the Hanford Site. Over the past few years at the DWPF, work has concentrated on increasing waste throughput. These efforts are continuing with an emphasis on high alumina content feeds. High alumina feeds have presented specific challenges for the JHM technology regarding the ability to increase waste loading yet still maintain product quality and adequate throughput. Alternatively, vitrification technology innovations are also being investigated as a means to increase waste throughput. The Cold Crucible Induction Melter (CCIM) technology affords the opportunity for higher vitrification process temperatures as compared to the current reference JHM technology. Higher process temperatures may allow for higher waste loading and higher melt rate. Glass formulation testing to support melter demonstration testing was recently completed. This testing was specifically aimed at high alumina concentration wastes. Glass composition property models were utilized as a guide for formulation development. Both CCIM and JHM testing will be conducted so glass formulation testing was targeted at both technologies with a goal to significantly increase waste loading without compromising product quality.

  2. Removal of cesium from a high-level calcined waste by high temperature volatilization

    SciTech Connect

    Del Debbio, J.A.

    1994-11-01

    Pyrochemical methods are being evaluated for the separation of actinides and fission products from inert material in high-level waste calcine. Separation processes have the potential of reducing waste disposal costs by reducing the volume of high-level waste requiring final disposal in a repository. Tests were conducted to evaluate high temperature volatilization for removing {sup 137}Cs from four types of calcines. The results for pilot plant calcines indicate greater than 99% cesium removal for alumina and fluorinel/sodium calcines heated at 1000{degree}C and 99% removal for zirconia calcine heated at 1100{degree}C. Tests with actual calcine generated at the New Waste Calcining Facility (NWCF) from a blend of aluminium, sodium and zirconium/fluorinel wastes resulted in 96% cesium removal at 1000{degree}C and greater than 99% removal at 1170{degree}C.

  3. Handbook of high-level radioactive waste transportation

    SciTech Connect

    Sattler, L.R.

    1992-10-01

    The High-Level Radioactive Waste Transportation Handbook serves as a reference to which state officials and members of the general public may turn for information on radioactive waste transportation and on the federal government`s system for transporting this waste under the Civilian Radioactive Waste Management Program. The Handbook condenses and updates information contained in the Midwestern High-Level Radioactive Waste Transportation Primer. It is intended primarily to assist legislators who, in the future, may be called upon to enact legislation pertaining to the transportation of radioactive waste through their jurisdictions. The Handbook is divided into two sections. The first section places the federal government`s program for transporting radioactive waste in context. It provides background information on nuclear waste production in the United States and traces the emergence of federal policy for disposing of radioactive waste. The second section covers the history of radioactive waste transportation; summarizes major pieces of legislation pertaining to the transportation of radioactive waste; and provides an overview of the radioactive waste transportation program developed by the US Department of Energy (DOE). To supplement this information, a summary of pertinent federal and state legislation and a glossary of terms are included as appendices, as is a list of publications produced by the Midwestern Office of The Council of State Governments (CSG-MW) as part of the Midwestern High-Level Radioactive Waste Transportation Project.

  4. Gelcasting polycrystalline alumina

    SciTech Connect

    Janney, M.A.

    1997-04-01

    This work is being done as part of a CRADA with Osram-Sylvania, Inc. (OSI) OSI is a major U.S. manufacturer of high-intensity lighting. Among its products is the Lumalux{reg_sign} line of high-pressure sodium vapor arc lamps, which are used for industrial, highway, and street lighting. The key to the performance of these lamps is the polycrystalline alumina (PCA) tube that is used to contain the plasma that is formed in the electric arc. That plasma consists of ionized sodium, mercury, and xenon vapors. The key attributes of the PCA tubes are their transparency (95% total transmittance in the visible region), their refractoriness (inner wall temperature can reach 1400{degrees}C), and their chemical resistance (sodium and mercury vapor are extremely corrosive). The current efficiency of the lamps is very high, on the order of several hundred lumens / watt. (Compare - incandescent lamps -13 lumens/watt fluorescent lamps -30 lumens/watt.) Osram-Sylvania would like to explore using gelcasting to form PCA tubes for Lumalux{reg_sign} lamps, and eventually for metal halide lamps (known as quartz-halogen lamps). Osram-Sylvania, Inc. currently manufactures PCA tubes by isostatic pressing. This process works well for the shapes that they presently use. However, there are several types of tubes that are either difficult or impossible to make by isostatic pressing. It is the desire to make these new shapes and sizes of tubes that has prompted Osram-Sylvania`s interest in gelcasting. The purpose of the CRADA is to determine the feasibility of making PCA items having sufficient optical quality that they are useful in lighting applications using gelcasting.

  5. EAP high-level product architecture

    NASA Astrophysics Data System (ADS)

    Gudlaugsson, T. V.; Mortensen, N. H.; Sarban, R.

    2013-04-01

    EAP technology has the potential to be used in a wide range of applications. This poses the challenge to the EAP component manufacturers to develop components for a wide variety of products. Danfoss Polypower A/S is developing an EAP technology platform, which can form the basis for a variety of EAP technology products while keeping complexity under control. High level product architecture has been developed for the mechanical part of EAP transducers, as the foundation for platform development. A generic description of an EAP transducer forms the core of the high level product architecture. This description breaks down the EAP transducer into organs that perform the functions that may be present in an EAP transducer. A physical instance of an EAP transducer contains a combination of the organs needed to fulfill the task of actuator, sensor, and generation. Alternative principles for each organ allow the function of the EAP transducers to be changed, by basing the EAP transducers on a different combination of organ alternatives. A model providing an overview of the high level product architecture has been developed to support daily development and cooperation across development teams. The platform approach has resulted in the first version of an EAP technology platform, on which multiple EAP products can be based. The contents of the platform have been the result of multi-disciplinary development work at Danfoss PolyPower, as well as collaboration with potential customers and research institutions. Initial results from applying the platform on demonstrator design for potential applications are promising. The scope of the article does not include technical details.

  6. The CMS High-Level Trigger

    SciTech Connect

    Covarelli, R.

    2009-12-17

    At the startup of the LHC, the CMS data acquisition is expected to be able to sustain an event readout rate of up to 100 kHz from the Level-1 trigger. These events will be read into a large processor farm which will run the 'High-Level Trigger'(HLT) selection algorithms and will output a rate of about 150 Hz for permanent data storage. In this report HLT performances are shown for selections based on muons, electrons, photons, jets, missing transverse energy, {tau} leptons and b quarks: expected efficiencies, background rates and CPU time consumption are reported as well as relaxation criteria foreseen for a LHC startup instantaneous luminosity.

  7. The effects of high level infrasound

    SciTech Connect

    Johnson, D.L.

    1980-02-01

    This paper will attempt to survey the current knowledge on the effects of relative high levels of infrasound on humans. While this conference is concerned mainly about hearing, some discussion of other physiological effects is appropriate. Such discussion also serves to highlight a basic question, 'Is hearing the main concern of infrasound and low frequency exposure, or is there a more sensitive mechanism'. It would be comforting to know that the focal point of this conference is indeed the most important concern. Therefore, besides hearing loss and auditory threshold of infrasonic and low frequency exposure, four other effects will be provided. These are performance, respiration, annoyance, and vibration.

  8. Service Oriented Architecture for High Level Applications

    SciTech Connect

    Chu, Chungming; Chevtsov, Sergei; Wu, Juhao; Shen, Guobao; /Brookhaven

    2012-06-28

    Standalone high level applications often suffer from poor performance and reliability due to lengthy initialization, heavy computation and rapid graphical update. Service-oriented architecture (SOA) is trying to separate the initialization and computation from applications and to distribute such work to various service providers. Heavy computation such as beam tracking will be done periodically on a dedicated server and data will be available to client applications at all time. Industrial standard service architecture can help to improve the performance, reliability and maintainability of the service. Robustness will also be improved by reducing the complexity of individual client applications.

  9. Corrosion model validation in high level nuclear package research

    SciTech Connect

    McNeil, M.B.; Moody, J.B.

    1993-12-31

    The strategies for waste package (WP) performance validation will be based on site specific geologic and hydrogeochemical information plus models which can be used to predict potential WP lifetimes. The development and application of such models will include the evaluation of natural analogues (NA). These analogues are needed to resolve issues related to the validation of models. Natural analogues have not had extensive use or widespread acceptance in the area of waste package failure prediction. This lack of acceptance is due to the anticipated choice of alloys for waste package containers. Few of these alloys are similar to naturally occurring metals, and the proposed HLW repositories are in general in geologic settings not very similar to those in which naturally occurring metals are generally found. Natural and archaeological analogues can be used, however, in analysis of possible waste package failures as a means of testing proposed models for failure. In fact, the analogues are the only available mechanisms for testing models of long-term waste package behavior. A strategy is outlined for incorporating natural and archaeological analogue studies into waste package research, and examples are discussed. The natural/archaeological analogous approach which appears most promising is to use archaeological and mineral samples to develop an understanding of the identities and rates of the mineral alteration reactions at or near the surface of the package, improving present capability for estimating the lifetimes of metallic waste package containers.

  10. High level intelligent control of telerobotics systems

    NASA Technical Reports Server (NTRS)

    Mckee, James

    1988-01-01

    A high level robot command language is proposed for the autonomous mode of an advanced telerobotics system and a predictive display mechanism for the teleoperational model. It is believed that any such system will involve some mixture of these two modes, since, although artificial intelligence can facilitate significant autonomy, a system that can resort to teleoperation will always have the advantage. The high level command language will allow humans to give the robot instructions in a very natural manner. The robot will then analyze these instructions to infer meaning so that is can translate the task into lower level executable primitives. If, however, the robot is unable to perform the task autonomously, it will switch to the teleoperational mode. The time delay between control movement and actual robot movement has always been a problem in teleoperations. The remote operator may not actually see (via a monitor) the results of high actions for several seconds. A computer generated predictive display system is proposed whereby the operator can see a real-time model of the robot's environment and the delayed video picture on the monitor at the same time.

  11. Technetium Chemistry in High-Level Waste

    SciTech Connect

    Hess, Nancy J.

    2006-06-01

    Tc contamination is found within the DOE complex at those sites whose mission involved extraction of plutonium from irradiated uranium fuel or isotopic enrichment of uranium. At the Hanford Site, chemical separations and extraction processes generated large amounts of high level and transuranic wastes that are currently stored in underground tanks. The waste from these extraction processes is currently stored in underground High Level Waste (HLW) tanks. However, the chemistry of the HLW in any given tank is greatly complicated by repeated efforts to reduce volume and recover isotopes. These processes ultimately resulted in mixing of waste streams from different processes. As a result, the chemistry and the fate of Tc in HLW tanks are not well understood. This lack of understanding has been made evident in the failed efforts to leach Tc from sludge and to remove Tc from supernatants prior to immobilization. Although recent interest in Tc chemistry has shifted from pretreatment chemistry to waste residuals, both needs are served by a fundamental understanding of Tc chemistry.

  12. Nickel in high-alumina basalts

    USGS Publications Warehouse

    Hedge, C.E.

    1971-01-01

    New analyses of high-alumina basalts reveal an average nickel content higher than previously indicated. Ni in high-alumina basalts correlates with magnesium in the same way as it does in other basalt types. There is therefore no reason, based on Ni contents, to hypothesize a special origin for high-alumina basalts and it is permissible (based on Ni contents) to form andesites by fractional crystallization from high-alumina basalts. ?? 1971.

  13. The nature and impacts of fines in smelter-grade alumina

    NASA Astrophysics Data System (ADS)

    Perander, Linus M.; Zujovic, Zoran D.; Kemp, Tom F.; Smith, Mark E.; Metson, James B.

    2009-11-01

    Fines in smelter-grade aluminas are recognized as a significant process problem in aluminum smelting. However, understanding the nature of this fine material and how it impacts the reduction process are less clearly understood. The combination of new analytical methods such as variable pressure scanning electron microscopy and very high field solid state nuclear magnetic resonance provide new insights into the phases present and their spatial distribution within aluminas, and suggest how such fine materials are generated, particularly during calcination in the alumina refinery.

  14. Attrition resistant gamma-alumina catalyst support

    DOEpatents

    Singleton, Alan H.; Oukaci, Rachid; Goodwin, James G.

    2006-03-14

    A .gamma.-alumina catalyst support having improved attrition resistance produced by a method comprising the steps of treating a particulate .gamma.-alumina material with an acidic aqueous solution comprising water and nitric acid and then, prior to adding any catalytic material thereto, calcining the treated .gamma.-alumina.

  15. High-level connectionist models. Semiannual report

    SciTech Connect

    Pollack, J.B.

    1989-08-01

    The major achievement of this semiannum was the significant revision and extension of the Recursive Auto-Associative Memory (RAAM) work for publication in the journal Artificial Intelligence. Included as an appendix to this report, the article includes several new elements: (1) Background - The work was more clearly set into the area of recursive distributed representations, machine learning, and the adequacy of the connectionist approach for high-level cognitive modeling; (2) New Experiment - RAAM was applied to finding compact representations for sequences of letters; (3) Analysis - The developed representations were analyzed as features which range from categorical to distinctive. Categorical features distinguish between conceptual categories while distinctive features vary within categories and discriminate or label the members. The representations were also analyzed geometrically; and (4) Applications - Feasibility studies were performed and described on inference by association, and on using RAAM-generated patterns along with cascaded networks for natural language parsing. Both of these remain long-term goals of the project.

  16. Umbra's High Level Architecture (HLA) Interface

    SciTech Connect

    GOTTLIEB, ERIC JOSEPH; MCDONALD, MICHAEL J.; OPPEL III, FRED J.

    2002-04-01

    This report describes Umbra's High Level Architecture HLA library. This library serves as an interface to the Defense Simulation and Modeling Office's (DMSO) Run Time Infrastructure Next Generation Version 1.3 (RTI NG1.3) software library and enables Umbra-based models to be federated into HLA environments. The Umbra library was built to enable the modeling of robots for military and security system concept evaluation. A first application provides component technologies that ideally fit the US Army JPSD's Joint Virtual Battlespace (JVB) simulation framework for Objective Force concept analysis. In addition to describing the Umbra HLA library, the report describes general issues of integrating Umbra with RTI code and outlines ways of building models to support particular HLA simulation frameworks like the JVB.

  17. Airway injury during high-level exercise.

    PubMed

    Kippelen, Pascale; Anderson, Sandra D

    2012-05-01

    Airway epithelial cells act as a physical barrier against environmental toxins and injury, and modulate inflammation and the immune response. As such, maintenance of their integrity is critical. Evidence is accumulating to suggest that exercise can cause injury to the airway epithelium. This seems the case particularly for competitive athletes performing high-level exercise, or when exercise takes place in extreme environmental conditions such as in cold dry air or in polluted air. Dehydration of the small airways and increased forces exerted on to the airway surface during severe hyperpnoea are thought to be key factors in determining the occurrence of injury of the airway epithelium. The injury-repair process of the airway epithelium may contribute to the development of the bronchial hyper-responsiveness that is documented in many elite athletes. PMID:22247295

  18. The High Level Data Reduction Library

    NASA Astrophysics Data System (ADS)

    Ballester, P.; Gabasch, A.; Jung, Y.; Modigliani, A.; Taylor, J.; Coccato, L.; Freudling, W.; Neeser, M.; Marchetti, E.

    2015-09-01

    The European Southern Observatory (ESO) provides pipelines to reduce data for most of the instruments at its Very Large telescope (VLT). These pipelines are written as part of the development of VLT instruments, and are used both in the ESO's operational environment and by science users who receive VLT data. All the pipelines are highly specific geared toward instruments. However, experience showed that the independently developed pipelines include significant overlap, duplication and slight variations of similar algorithms. In order to reduce the cost of development, verification and maintenance of ESO pipelines, and at the same time improve the scientific quality of pipelines data products, ESO decided to develop a limited set of versatile high-level scientific functions that are to be used in all future pipelines. The routines are provided by the High-level Data Reduction Library (HDRL). To reach this goal, we first compare several candidate algorithms and verify them during a prototype phase using data sets from several instruments. Once the best algorithm and error model have been chosen, we start a design and implementation phase. The coding of HDRL is done in plain C and using the Common Pipeline Library (CPL) functionality. HDRL adopts consistent function naming conventions and a well defined API to minimise future maintenance costs, implements error propagation, uses pixel quality information, employs OpenMP to take advantage of multi-core processors, and is verified with extensive unit and regression tests. This poster describes the status of the project and the lesson learned during the development of reusable code implementing algorithms of high scientific quality.

  19. Alumina-Enhanced Thermal Barrier

    NASA Technical Reports Server (NTRS)

    Smith, Marnell; Leiser, Dan; Goldstein, Howard

    1989-01-01

    Rigid, fibrous ceramic tile material called "alumina-enhanced thermal barrier" (AETB) extends temperature capability of insulating materials. Material has obvious potential for terrestrial use in kilns, furnaces, heat engines, and other applications in which light weight and high operating temperature are specified. Three kinds of ceramic fibers are blended, molded, and sintered to make refractory tiles.

  20. Performance of the CMS High Level Trigger

    NASA Astrophysics Data System (ADS)

    Perrotta, Andrea

    2015-12-01

    The CMS experiment has been designed with a 2-level trigger system. The first level is implemented using custom-designed electronics. The second level is the so-called High Level Trigger (HLT), a streamlined version of the CMS offline reconstruction software running on a computer farm. For Run II of the Large Hadron Collider, the increases in center-of-mass energy and luminosity will raise the event rate to a level challenging for the HLT algorithms. The increase in the number of interactions per bunch crossing, on average 25 in 2012, and expected to be around 40 in Run II, will be an additional complication. We present here the expected performance of the main triggers that will be used during the 2015 data taking campaign, paying particular attention to the new approaches that have been developed to cope with the challenges of the new run. This includes improvements in HLT electron and photon reconstruction as well as better performing muon triggers. We will also present the performance of the improved tracking and vertexing algorithms, discussing their impact on the b-tagging performance as well as on the jet and missing energy reconstruction.

  1. CMS High Level Trigger Timing Measurements

    NASA Astrophysics Data System (ADS)

    Richardson, Clint

    2015-12-01

    The two-level trigger system employed by CMS consists of the Level 1 (L1) Trigger, which is implemented using custom-built electronics, and the High Level Trigger (HLT), a farm of commercial CPUs running a streamlined version of the offline CMS reconstruction software. The operational L1 output rate of 100 kHz, together with the number of CPUs in the HLT farm, imposes a fundamental constraint on the amount of time available for the HLT to process events. Exceeding this limit impacts the experiment's ability to collect data efficiently. Hence, there is a critical need to characterize the performance of the HLT farm as well as the algorithms run prior to start up in order to ensure optimal data taking. Additional complications arise from the fact that the HLT farm consists of multiple generations of hardware and there can be subtleties in machine performance. We present our methods of measuring the timing performance of the CMS HLT, including the challenges of making such measurements. Results for the performance of various Intel Xeon architectures from 2009-2014 and different data taking scenarios are also presented.

  2. HIGH LEVEL RF FOR THE SNS RING.

    SciTech Connect

    ZALTSMAN,A.; BLASKIEWICZ,M.; BRENNAN,J.; BRODOWSKI,J.; METH,M.; SPITZ,R.; SEVERINO,F.

    2002-06-03

    A high level RF system (HLRF) consisting of power amplifiers (PA's) and ferrite loaded cavities is being designed and built by Brookhaven National Laboratory (BNL) for the Spallation Neutron Source (SNS) project. It is a fixed frequency, two harmonic system whose main function is to maintain a gap for the kicker rise time. Three cavities running at the fundamental harmonic (h=l) will provide 40 kV and one cavity at the second harmonic (h=2) will provide 20 kV. Each cavity has two gaps with a design voltage of 10 kV per gap and will be driven by a power amplifier (PA) directly adjacent to it. The PA uses a 600kW tetrode to provide the necessary drive current. The anode of the tetrode is magnetically coupled to the downstream cell of the cavity. Drive to the PA will be provided by a wide band, solid state amplifier located remotely. A dynamic tuning scheme will be implemented to help compensate for the effect of beam loading.

  3. Decontamination of high-level waste canisters

    SciTech Connect

    Nesbitt, J.F.; Slate, S.C.; Fetrow, L.K.

    1980-12-01

    This report presents evaluations of several methods for the in-process decontamination of metallic canisters containing any one of a number of solidified high-level waste (HLW) forms. The use of steam-water, steam, abrasive blasting, electropolishing, liquid honing, vibratory finishing and soaking have been tested or evaluated as potential techniques to decontaminate the outer surfaces of HLW canisters. Either these techniques have been tested or available literature has been examined to assess their applicability to the decontamination of HLW canisters. Electropolishing has been found to be the most thorough method to remove radionuclides and other foreign material that may be deposited on or in the outer surface of a canister during any of the HLW processes. Steam or steam-water spraying techniques may be adequate for some applications but fail to remove all contaminated forms that could be present in some of the HLW processes. Liquid honing and abrasive blasting remove contamination and foreign material very quickly and effectively from small areas and components although these blasting techniques tend to disperse the material removed from the cleaned surfaces. Vibratory finishing is very capable of removing the bulk of contamination and foreign matter from a variety of materials. However, special vibratory finishing equipment would have to be designed and adapted for a remote process. Soaking techniques take long periods of time and may not remove all of the smearable contamination. If soaking involves pickling baths that use corrosive agents, these agents may cause erosion of grain boundaries that results in rough surfaces.

  4. Sintering and mechanical properties of the alumina-tricalcium phosphate-titania composites.

    PubMed

    Sakka, Siwar; Bouaziz, Jamel; Ben Ayed, Foued

    2014-07-01

    The objective of this study was to determine the effect of the content of titania and the sintering process on the transformation phase, the densification, the rupture strength and the microstructures of the alumina-10 wt.% tricalcium phosphate composites. After the sintering process, the samples were examined by using (31)P and (27)Al magic angle scanning nuclear magnetic resonance, X-ray powder diffraction and scanning electron microscopy analysis. The Brazilian test was used to measure the rupture strength of the samples. The present results provide new information about solid-state reactivity in the ternary system α-alumina-β-tricalcium phosphate-anatase-titania. The differential thermal analysis of the α-alumina-β-tricalcium phosphate-titania composites shows two endothermic peaks, at 1360 °C and at 1405 °C, which are caused by the reactions between titania/alumina and titania/tricalcium phosphate, respectively. Thus, the presence of titania in the alumina-10 wt.% tricalcium phosphate leads to the formation of β-Al2TiO5 at 1360 °C. At 1600 °C, the alumina-10 wt.% tricalcium phosphate-5 wt.% titania composites displayed the highest rupture strength (74 MPa), compared to the alumina-10 wt.% tricalcium phosphate composites (13.5 MPa). Accordingly, the increase of the rupture strength is due to the formation of the new β-Al2TiO5 phase. PMID:24857470

  5. Development of a High Level Waste Tank Inspection System

    SciTech Connect

    Appel, D.K.; Loibl, M.W.; Meese, D.C.

    1995-03-21

    The Westinghouse Savannah River Technology Center was requested by it`s sister site, West Valley Nuclear Service (WVNS), to develop a remote inspection system to gather wall thickness readings of their High Level Waste Tanks. WVNS management chose to take a proactive approach to gain current information on two tanks t hat had been in service since the early 70`s. The tanks contain high level waste, are buried underground, and have only two access ports to an annular space between the tank and the secondary concrete vault. A specialized remote system was proposed to provide both a visual surveillance and ultrasonic thickness measurements of the tank walls. A magnetic wheeled crawler was the basis for the remote delivery system integrated with an off-the-shelf Ultrasonic Data Acquisition System. A development program was initiated for Savannah River Technology Center (SRTC) to design, fabricate, and test a remote system based on the Crawler. The system was completed and involved three crawlers to perform the needed tasks, an Ultrasonic Crawler, a Camera Crawler, and a Surface Prep Crawler. The crawlers were computer controlled so that their operation could be done remotely and their position on the wall could be tracked. The Ultrasonic Crawler controls were interfaced with ABB Amdata`s I-PC, Ultrasonic Data Acquisition System so that thickness mapping of the wall could be obtained. A second system was requested by Westinghouse Savannah River Company (WSRC), to perform just ultrasonic mapping on their similar Waste Storage Tanks; however, the system needed to be interfaced with the P-scan Ultrasonic Data Acquisition System. Both remote inspection systems were completed 9/94. Qualifications tests were conducted by WVNS prior to implementation on the actual tank and tank development was achieved 10/94. The second inspection system was deployed at WSRC 11/94 with success, and the system is now in continuous service inspecting the remaining high level waste tanks at WSRC.

  6. Defense High Level Waste Disposal Container System Description Document

    SciTech Connect

    N. E. Pettit

    2001-07-13

    The Defense High Level Waste Disposal Container System supports the confinement and isolation of waste within the Engineered Barrier System of the Monitored Geologic Repository (MGR). Disposal containers are loaded and sealed in the surface waste handling facilities, transferred to the underground through the accesses using a rail mounted transporter, and emplaced in emplacement drifts. The defense high level waste (HLW) disposal container provides long-term confinement of the commercial HLW and defense HLW (including immobilized plutonium waste forms [IPWF]) placed within disposable canisters, and withstands the loading, transfer, emplacement, and retrieval loads and environments. US Department of Energy (DOE)-owned spent nuclear fuel (SNF) in disposable canisters may also be placed in a defense HLW disposal container along with commercial HLW waste forms, which is known as co-disposal. The Defense High Level Waste Disposal Container System provides containment of waste for a designated period of time, and limits radionuclide release. The disposal container/waste package maintains the waste in a designated configuration, withstands maximum handling and rockfall loads, limits the individual canister temperatures after emplacement, resists corrosion in the expected handling and repository environments, and provides containment of waste in the event of an accident. Defense HLW disposal containers for HLW disposal will hold up to five HLW canisters. Defense HLW disposal containers for co-disposal will hold up to five HLW canisters arranged in a ring and one DOE SNF canister inserted in the center and/or one or more DOE SNF canisters displacing a HLW canister in the ring. Defense HLW disposal containers also will hold two Multi-Canister Overpacks (MCOs) and two HLW canisters in one disposal container. The disposal container will include outer and inner cylinders, outer and inner cylinder lids, and may include a canister guide. An exterior label will provide a means by

  7. Space augmentation of military high-level waste disposal

    NASA Technical Reports Server (NTRS)

    English, T.; Lees, L.; Divita, E.

    1979-01-01

    Space disposal of selected components of military high-level waste (HLW) is considered. This disposal option offers the promise of eliminating the long-lived radionuclides in military HLW from the earth. A space mission which meets the dual requirements of long-term orbital stability and a maximum of one space shuttle launch per week over a period of 20-40 years, is a heliocentric orbit about halfway between the orbits of earth and Venus. Space disposal of high-level radioactive waste is characterized by long-term predictability and short-term uncertainties which must be reduced to acceptably low levels. For example, failure of either the Orbit Transfer Vehicle after leaving low earth orbit, or the storable propellant stage failure at perihelion would leave the nuclear waste package in an unplanned and potentially unstable orbit. Since potential earth reencounter and subsequent burn-up in the earth's atmosphere is unacceptable, a deep space rendezvous, docking, and retrieval capability must be developed.

  8. FLUIDIZED BED STEAM REFORMING ENABLING ORGANIC HIGH LEVEL WASTE DISPOSAL

    SciTech Connect

    Williams, M

    2008-05-09

    Waste streams planned for generation by the Global Nuclear Energy Partnership (GNEP) and existing radioactive High Level Waste (HLW) streams containing organic compounds such as the Tank 48H waste stream at Savannah River Site have completed simulant and radioactive testing, respectfully, by Savannah River National Laboratory (SRNL). GNEP waste streams will include up to 53 wt% organic compounds and nitrates up to 56 wt%. Decomposition of high nitrate streams requires reducing conditions, e.g. provided by organic additives such as sugar or coal, to reduce NOX in the off-gas to N2 to meet Clean Air Act (CAA) standards during processing. Thus, organics will be present during the waste form stabilization process regardless of the GNEP processes utilized and exists in some of the high level radioactive waste tanks at Savannah River Site and Hanford Tank Farms, e.g. organics in the feed or organics used for nitrate destruction. Waste streams containing high organic concentrations cannot be stabilized with the existing HLW Best Developed Available Technology (BDAT) which is HLW vitrification (HLVIT) unless the organics are removed by pretreatment. The alternative waste stabilization pretreatment process of Fluidized Bed Steam Reforming (FBSR) operates at moderate temperatures (650-750 C) compared to vitrification (1150-1300 C). The FBSR process has been demonstrated on GNEP simulated waste and radioactive waste containing high organics from Tank 48H to convert organics to CAA compliant gases, create no secondary liquid waste streams and create a stable mineral waste form.

  9. DEFENSE HIGH LEVEL WASTE GLASS DEGRADATION

    SciTech Connect

    W. Ebert

    2001-09-20

    The purpose of this Analysis/Model Report (AMR) is to document the analyses that were done to develop models for radionuclide release from high-level waste (HLW) glass dissolution that can be integrated into performance assessment (PA) calculations conducted to support site recommendation and license application for the Yucca Mountain site. This report was developed in accordance with the ''Technical Work Plan for Waste Form Degradation Process Model Report for SR'' (CRWMS M&O 2000a). It specifically addresses the item, ''Defense High Level Waste Glass Degradation'', of the product technical work plan. The AP-3.15Q Attachment 1 screening criteria determines the importance for its intended use of the HLW glass model derived herein to be in the category ''Other Factors for the Postclosure Safety Case-Waste Form Performance'', and thus indicates that this factor does not contribute significantly to the postclosure safety strategy. Because the release of radionuclides from the glass will depend on the prior dissolution of the glass, the dissolution rate of the glass imposes an upper bound on the radionuclide release rate. The approach taken to provide a bound for the radionuclide release is to develop models that can be used to calculate the dissolution rate of waste glass when contacted by water in the disposal site. The release rate of a particular radionuclide can then be calculated by multiplying the glass dissolution rate by the mass fraction of that radionuclide in the glass and by the surface area of glass contacted by water. The scope includes consideration of the three modes by which water may contact waste glass in the disposal system: contact by humid air, dripping water, and immersion. The models for glass dissolution under these contact modes are all based on the rate expression for aqueous dissolution of borosilicate glasses. The mechanism and rate expression for aqueous dissolution are adequately understood; the analyses in this AMR were conducted to

  10. The high-level trigger of ALICE

    NASA Astrophysics Data System (ADS)

    Tilsner, H.; Alt, T.; Aurbakken, K.; Grastveit, G.; Helstrup, H.; Lindenstruth, V.; Loizides, C.; Nystrand, J.; Roehrich, D.; Skaali, B.; Steinbeck, T.; Ullaland, K.; Vestbo, A.; Vik, T.

    One of the main tracking detectors of the forthcoming ALICE Experiment at the LHC is a cylindrical Time Projection Chamber (TPC) with an expected data volume of about 75 MByte per event. This data volume, in combination with the presumed maximum bandwidth of 1.2 GByte/s to the mass storage system, would limit the maximum event rate to 20 Hz. In order to achieve higher event rates, online data processing has to be applied. This implies either the detection and read-out of only those events which contain interesting physical signatures or an efficient compression of the data by modeling techniques. In order to cope with the anticipated data rate, massive parallel computing power is required. It will be provided in form of a clustered farm of SMP-nodes, based on off-the-shelf PCs, which are connected with a high bandwidth low overhead network. This High-Level Trigger (HLT) will be able to process a data rate of 25 GByte/s online. The front-end electronics of the individual sub-detectors is connected to the HLT via an optical link and a custom PCI card which is mounted in the clustered PCs. The PCI card is equipped with an FPGA necessary for the implementation of the PCI-bus protocol. Therefore, this FPGA can also be used to assist the host processor with first-level processing. The first-level processing done on the FPGA includes conventional cluster-finding for low multiplicity events and local track finding based on the Hough Transformation of the raw data for high multiplicity events. PACS: 07.05.-t Computers in experimental physics - 07.05.Hd Data acquisition: hardware and software - 29.85.+c Computer data analysis

  11. High-level waste tank farm set point document

    SciTech Connect

    Anthony, J.A. III

    1995-01-15

    Setpoints for nuclear safety-related instrumentation are required for actions determined by the design authorization basis. Minimum requirements need to be established for assuring that setpoints are established and held within specified limits. This document establishes the controlling methodology for changing setpoints of all classifications. The instrumentation under consideration involve the transfer, storage, and volume reduction of radioactive liquid waste in the F- and H-Area High-Level Radioactive Waste Tank Farms. The setpoint document will encompass the PROCESS AREA listed in the Safety Analysis Report (SAR) (DPSTSA-200-10 Sup 18) which includes the diversion box HDB-8 facility. In addition to the PROCESS AREAS listed in the SAR, Building 299-H and the Effluent Transfer Facility (ETF) are also included in the scope.

  12. Packed Alumina Absorbs Hypergolic Vapors

    NASA Technical Reports Server (NTRS)

    Thomas, J. J.; Mauro, D. M.

    1984-01-01

    Beds of activated alumina effective as filters to remove hypergolic vapors from gas streams. Beds absorb such substances as nitrogen oxides and hydrazines and may also absorb acetylene, ethylene, hydrogen sulfide, benzene, butadiene, butene, styrene, toluene, and xoylene. Bed has no moving parts such as pumps, blowers and mixers. Reliable and energy-conservative. Bed readily adapted to any size from small portable units for use where little vapor release is expected to large stationary units for extensive transfer operations.

  13. Stuies of neptunium(V) sorption on montmorillonite, clinoptilolite, quartz and {alpha}-alumina

    SciTech Connect

    Bertetti, F.P.; Pabalan, R.T.; Turner, D.R.; Almendarez, M.G.

    1996-10-01

    {sup 237}Np is a particular concern to the safety suitability of Yucca Mountain, Nevada, as a geologic repository for high-level nuclear wastes. In this study, montmorillonite, clinoptilolite, quartz, and {alpha}-alumina were reacted with {sup 237}Np-bearing solutions to characterize the sorption behavior of Np(V) on these minerals. Batch experiments were conducted at room temperature (20{plus_minus}2{degrees}C) over a range of conditions in which solution pH, sorbent surface area, initial concentration of N(V), ionic strength, and partial pressure of CO{sub 2} were varied. For all the minerals studied, Np(V) sorption begins at pH values coincident with the start of Np hydrolysis in solution ({approximately}6.5-7). For solutions undersaturated with respect to atmospheric CO{sub 2}, sorption increases continuously with increasing pH. For solutions at equilibrium with atmospheric CO{sub 2}, the {open_quotes}sorption envelope{close_quotes} is coincident with the calculated predominance field (pH {approximately}7-9.5) of the NpO{sub 2}(OH){sup 0}(aq) species, and sorption is inhibited at higher pH where neptunyl carbonate complexes predominate. Modeling of the sorption behavior of Np(V) was performed using a surface complexation-approach (Diffuse-Layer Model).

  14. Method for preparing Pb-. beta. ''-alumina ceramic

    DOEpatents

    Hellstrom, E.E.

    1984-08-30

    A process is disclosed for preparing impermeable, polycrystalline samples of Pb-..beta..''-alumina ceramic from Na-..beta..''-alumina ceramic by ion exchange. The process comprises two steps. The first step is a high-temperature vapor phase exchange of Na by K, followed by substitution of Pb for K by immersing the sample in a molten Pb salt bath. The result is a polycrystalline Pb-..beta..''-alumina ceramic that is substantially crack-free.

  15. Structural transitions in alumina nanoparticles by heat treatment

    NASA Astrophysics Data System (ADS)

    Kaur, Nirmal; Khanna, Atul; Chen, Banghao; González, Fernando

    2016-05-01

    γ-alumina nanoparticles were annealed sequentially at 800°C, 950°C and 1100°C and structural transitions as a function of heat treatment were studied by X-ray diffraction (XRD), Differential Scanning Calorimetry (DSC) and 27Al Magic Angle Spinning Nuclear Magnetic Resonance (MAS-NMR) methods.. XRD studies found that γ-Al2O3 is stable upto a temperature of at least 950°C and transforms to the thermodynamically stable α-phase after annealing at 1100°C. MAS-NMR revealed that γ-alumina contains AlO4 and AlO6 structural units in the ratio 1: 2, while α-phase contains only AlO6 units. DSC confirmed that γ → α transition initiates at 1060°C.

  16. Physical chemistry of carbothermic reduction of alumina

    SciTech Connect

    Frank, Robert A.

    1985-09-01

    Production of aluminium, by means of carbothermic reduction of alumina, is discussed. By employing a solvent metal bath to absorb the alumina metal, carbothermic reduction of alumina was accomplished at temperatures 300/degree/C lower than the temperatures reported in the literature. Reduction occurred without the formation of intermediate compounds and without the high volatilization of aluminum bearing species. Reduction of alumina immersed in a solvent bath appeared to be rate limited by chemical reaction control. The rates seemed to be a function of the activity of aluminum in the solvent metal bath. Reduction of alumina particles, above the surface of the bath, seemed to occur via vapor transport with carbon in the particles or in the crucible walls. Mass transport in the gas phase appeared to be rate limiting. The rates seemed to be a function of the distance separating the alumina and carbon sources. With both submerged alumina and alumina particles, increasing the surface area of the alumina increased the rate of reduction. 58 refs., 65 figs., 9 tabs.

  17. Microwave sintering of large alumina bodies

    SciTech Connect

    Blake, R.D.; Katz, J.D.

    1993-05-01

    The application of microwaves as an energy source for materials processing of large alumina bodies at elevated temperatures has been limited to date. Most work has concerned itself with small laboratory samples. The nonuniformity of the microwave field within a cavity subjects large alumina bodies to areas of concentrated energy, resulting in uneven heating and subsequent cracking. Smaller bodies are not significantly affected by field nonuniformity due to their smaller mass. This work will demonstrate a method for microwave sintering of large alumina bodies while maintaining their structural integrity. Several alumina configurations were successfully sintered using a method which creates an artificial field or environment within the microwave cavity.

  18. Microwave sintering of large alumina bodies

    SciTech Connect

    Blake, R.D.; Katz, J.D.

    1993-01-01

    The application of microwaves as an energy source for materials processing of large alumina bodies at elevated temperatures has been limited to date. Most work has concerned itself with small laboratory samples. The nonuniformity of the microwave field within a cavity subjects large alumina bodies to areas of concentrated energy, resulting in uneven heating and subsequent cracking. Smaller bodies are not significantly affected by field nonuniformity due to their smaller mass. This work will demonstrate a method for microwave sintering of large alumina bodies while maintaining their structural integrity. Several alumina configurations were successfully sintered using a method which creates an artificial field or environment within the microwave cavity.

  19. I-NERI-2007-004-K, DEVELOPMENT AND CHARACTERIZATION OF NEW HIGH-LEVEL WASTE FORMS FOR ACHIEVING WASTE MINIMIZATION FROM PYROPROCESSING

    SciTech Connect

    S.M. Frank

    2011-09-01

    Work describe in this report represents the final year activities for the 3-year International Nuclear Energy Research Initiative (I-NERI) project: Development and Characterization of New High-Level Waste Forms for Achieving Waste Minimization from Pyroprocessing. Used electrorefiner salt that contained actinide chlorides and was highly loaded with surrogate fission products was processed into three candidate waste forms. The first waste form, a high-loaded ceramic waste form is a variant to the CWF produced during the treatment of Experimental Breeder Reactor-II used fuel at the Idaho National Laboratory (INL). The two other waste forms were developed by researchers at the Korean Atomic Energy Research Institute (KAERI). These materials are based on a silica-alumina-phosphate matrix and a zinc/titanium oxide matrix. The proposed waste forms, and the processes to fabricate them, were designed to immobilize spent electrorefiner chloride salts containing alkali, alkaline earth, lanthanide, and halide fission products that accumulate in the salt during the processing of used nuclear fuel. This aspect of the I-NERI project was to demonstrate 'hot cell' fabrication and characterization of the proposed waste forms. The outline of the report includes the processing of the spent electrorefiner salt and the fabrication of each of the three waste forms. Also described is the characterization of the waste forms, and chemical durability testing of the material. While waste form fabrication and sample preparation for characterization must be accomplished in a radiological hot cell facility due to hazardous radioactivity levels, smaller quantities of each waste form were removed from the hot cell to perform various analyses. Characterization included density measurement, elemental analysis, x-ray diffraction, scanning electron microscopy and the Product Consistency Test, which is a leaching method to measure chemical durability. Favorable results from this demonstration project

  20. Deep borehole disposal of high-level radioactive waste.

    SciTech Connect

    Stein, Joshua S.; Freeze, Geoffrey A.; Brady, Patrick Vane; Swift, Peter N.; Rechard, Robert Paul; Arnold, Bill Walter; Kanney, Joseph F.; Bauer, Stephen J.

    2009-07-01

    Preliminary evaluation of deep borehole disposal of high-level radioactive waste and spent nuclear fuel indicates the potential for excellent long-term safety performance at costs competitive with mined repositories. Significant fluid flow through basement rock is prevented, in part, by low permeabilities, poorly connected transport pathways, and overburden self-sealing. Deep fluids also resist vertical movement because they are density stratified. Thermal hydrologic calculations estimate the thermal pulse from emplaced waste to be small (less than 20 C at 10 meters from the borehole, for less than a few hundred years), and to result in maximum total vertical fluid movement of {approx}100 m. Reducing conditions will sharply limit solubilities of most dose-critical radionuclides at depth, and high ionic strengths of deep fluids will prevent colloidal transport. For the bounding analysis of this report, waste is envisioned to be emplaced as fuel assemblies stacked inside drill casing that are lowered, and emplaced using off-the-shelf oilfield and geothermal drilling techniques, into the lower 1-2 km portion of a vertical borehole {approx}45 cm in diameter and 3-5 km deep, followed by borehole sealing. Deep borehole disposal of radioactive waste in the United States would require modifications to the Nuclear Waste Policy Act and to applicable regulatory standards for long-term performance set by the US Environmental Protection Agency (40 CFR part 191) and US Nuclear Regulatory Commission (10 CFR part 60). The performance analysis described here is based on the assumption that long-term standards for deep borehole disposal would be identical in the key regards to those prescribed for existing repositories (40 CFR part 197 and 10 CFR part 63).

  1. High-level hepatitis B virus replication in transgenic mice.

    PubMed Central

    Guidotti, L G; Matzke, B; Schaller, H; Chisari, F V

    1995-01-01

    Hepatitis B virus (HBV) transgenic mice whose hepatocytes replicate the virus at levels comparable to that in the infected livers of patients with chronic hepatitis have been produced, without any evidence of cytopathology. High-level viral gene expression was obtained in the liver and kidney tissues in three independent lineages. These animals were produced with a terminally redundant viral DNA construct (HBV 1.3) that starts just upstream of HBV enhancer I, extends completely around the circular viral genome, and ends just downstream of the unique polyadenylation site in HBV. In these animals, the viral mRNA is more abundant in centrilobular hepatocytes than elsewhere in the hepatic lobule. High-level viral DNA replication occurs inside viral nucleocapsid particles that preferentially form in the cytoplasm of these centrilobular hepatocytes, suggesting that an expression threshold must be reached for nucleocapsid assembly and viral replication to occur. Despite the restricted distribution of the viral replication machinery in centrilobular cytoplasmic nucleocapsids, nucleocapsid particles are detectable in the vast majority of hepatocyte nuclei throughout the hepatic lobule. The intranuclear nucleocapsid particles are empty, however, suggesting that viral nucleocapsid particle assembly occurs independently in the nucleus and the cytoplasm of the hepatocyte and implying that cytoplasmic nucleocapsid particles do not transport the viral genome across the nuclear membrane into the nucleus during the viral life cycle. This model creates the opportunity to examine the influence of viral and host factors on HBV pathogenesis and replication and to assess the antiviral potential of pharmacological agents and physiological processes, including the immune response. PMID:7666518

  2. Perfluoropolyalkylether decomposition on catalytic aluminas

    NASA Technical Reports Server (NTRS)

    Morales, Wilfredo

    1994-01-01

    The decomposition of Fomblin Z25, a commercial perfluoropolyalkylether liquid lubricant, was studied using the Penn State Micro-oxidation Test, and a thermal gravimetric/differential scanning calorimetry unit. The micro-oxidation test was conducted using 440C stainless steel and pure iron metal catalyst specimens, whereas the thermal gravimetric/differential scanning calorimetry tests were conducted using catalytic alumina pellets. Analysis of the thermal data, high pressure liquid chromatography data, and x-ray photoelectron spectroscopy data support evidence that there are two different decomposition mechanisms for Fomblin Z25, and that reductive sites on the catalytic surfaces are responsible for the decomposition of Fomblin Z25.

  3. Formation of alumina-nickel-molybdenum catalysts

    SciTech Connect

    Erofeev, V.I.; Basov, V.G.; Vagin, A.I.; Kalechits, I.V.

    1982-06-01

    On the basis of the results obtained in physical and chemical studies of alumina-nickel-molybdenum oxide catalysts as well as binary system and the individual oxides, the conclusions show that the commercial catalyst consists mainly of nickel and aluminium molybdates, aluminium molybdates, molybdenum oxide, and the alumina support. 4 figures.

  4. Effects of Impurities on Alumina-Niobium InterfacialMicrostructures

    SciTech Connect

    McKeown, Joseph T.; Sugar, Joshua D.; Gronsky, Ronald; Glaeser,Andreas M.

    2005-06-20

    Optical microscopy, scanning electron microscopy, and transmission electron microscopy were employed to examine the interfacial microstructural effects of impurities in alumina substrates used to fabricate alumina-niobium interfaces via liquid-film-assisted joining. Three types of alumina were used: undoped high-purity single-crystal sapphire; a high-purity, high-strength polycrystalline alumina; and a lower-purity, lower-strength polycrystalline alumina. Interfaces formed between niobium and both the sapphire and high-purity polycrystalline alumina were free of detectable levels of impurities. In the lower-purity alumina, niobium silicides were observed at the alumina-niobium interface and on alumina grain boundaries near the interface. These silicides formed in small-grained regions of the alumina and were found to grow from the interface into the alumina along grain boundaries. Smaller silicide precipitates found on grain boundaries are believed to form upon cooling from the bonding temperature.

  5. INCREASING SAFETY AND REDUCING ENVIRONMENTAL DAMAGE RISK FROM AGING HIGH-LEVEL RADIOACTIVE WASTE TANKS

    EPA Science Inventory

    There exists a paramount need for improved understanding of the behavior of high-level nuclear waste containers and the impact on structural integrity in terms of leak tightness and mechanical stability. The current program, which at the time of this writing is in its early stage...

  6. Review of high-level waste form properties. [146 bibliographies

    SciTech Connect

    Rusin, J.M.

    1980-12-01

    This report is a review of waste form options for the immobilization of high-level-liquid wastes from the nuclear fuel cycle. This review covers the status of international research and development on waste forms as of May 1979. Although the emphasis in this report is on waste form properties, process parameters are discussed where they may affect final waste form properties. A summary table is provided listing properties of various nuclear waste form options. It is concluded that proposed waste forms have properties falling within a relatively narrow range. In regard to crystalline versus glass waste forms, the conclusion is that either glass of crystalline materials can be shown to have some advantage when a single property is considered; however, at this date no single waste form offers optimum properties over the entire range of characteristics investigated. A long-term effort has been applied to the development of glass and calcine waste forms. Several additional waste forms have enough promise to warrant continued research and development to bring their state of development up to that of glass and calcine. Synthetic minerals, the multibarrier approach with coated particles in a metal matrix, and high pressure-high temperature ceramics offer potential advantages and need further study. Although this report discusses waste form properties, the total waste management system should be considered in the final selection of a waste form option. Canister design, canister materials, overpacks, engineered barriers, and repository characteristics, as well as the waste form, affect the overall performance of a waste management system. These parameters were not considered in this comparison.

  7. Preparation of plutonium waste forms with ICPP calcined high-level waste

    SciTech Connect

    Staples, B.A.; Knecht, D.A.; O`Holleran, T.P.

    1997-05-01

    Glass and glass-ceramic forms developed for the immobilization of calcined high-level wastes generated by Idaho Chemical Processing Plant (ICPP) fuel reprocessing activities have been investigated for ability to immobilize plutonium and to simultaneously incorporate calcined waste as an anti-proliferation barrier. Within the forms investigated, crystallization of host phases result in an increased loading of plutonium as well as its incorporation into potentially more durable phases than the glass. The host phases were initially formed and characterized with cerium (Ce{sup +4}) as a surrogate for plutonium (Pu{sup +4}) and samarium as a neutron absorber for criticality control. Verification of the surrogate testing results were then performed replacing cerium with plutonium. All testing was performed with surrogate calcined high-level waste. The results of these tests indicated that a potentially useful host phase, based on zirconia, can be formed either by devitrification or solid state reaction in the glass studied. This phase incorporates plutonium as well as samarium and the calcined waste becomes part of the matrix. Its ease of formation makes it potentially useful in excess plutonium dispositioning. Other durable host phases for plutonium and samarium, including zirconolite and zircon have been formed from zirconia or alumina calcine through cold press-sintering techniques and hot isostatic pressing. Host phase formation experiments conducted through vitrification or by cold press-sintering techniques are described and the results discussed. Recommendations are given for future work that extends the results of this study.

  8. ATW system impact on high-level waste

    SciTech Connect

    Arthur, E.D.

    1992-12-01

    This report discusses the Accelerator Transmutation of Waste (ATW) concept which aims at destruction of key long-lived radionuclides in high-level nuclear waste (HLW), both fission products and actinides. This focus makes it different from most other transmutation concepts which concentrate primarily on actinide burning. The ATW system uses an accelerator-driven, sub-critical assembly to create an intense thermal neutron environment for radionuclide transmutation. This feature allows rapid transmutation under low-inventory system conditions, which in turn, has a direct impact on the size of chemical separations and materials handling components of the system. Inventories in ATW are factors of eight to thirty times smaller than reactor systems of equivalent thermal power. Chemical separations systems are relatively small in scale and can be optimized to achieve high decontamination factors and minimized waste streams. The low-inventory feature also directly impacts material amounts remaining in the system at its end of life. In addition to its low-inventory operation, the accelerator-driven neutron source features of ATW are key to providing a sufficient level of neutrons to allow transmutation of long-lived fission products.

  9. Application of SYNROC to high-level defense wastes

    SciTech Connect

    Tewhey, J.D.; Hoenig, C.L.; Newkirk, H.W.; Rozsa, R.B.; Coles, D.G.; Ryerson, F.J.

    1981-01-01

    The SYNROC method for immobilization of high-level nuclear reactor wastes is currently being applied to US defense wastes in tank storage at Savannah River, South Carolina. The minerals zirconolite, perovskite, and hollandite are used in SYNROC D formulations to immobilize fission products and actinides that comprise up to 10% of defense waste sludges and coexisting solutions. Additional phases in SYNROC D are nepheline, the host phase for sodium; and spinel, the host for excess aluminum and iron. Up to 70 wt % of calcined sludge can be incorporated with 30 wt % of SYNROC additives to produce a waste form consisting of 10% nepheline, 30% spinel, and approximately 20% each of the radioactive waste-bearing phases. Urea coprecipitation and spray drying/calcining methods have been used in the laboratory to produce homogeneous, reactive ceramic powders. Hot pressing and sintering at temperatures from 1000 to 1100/sup 0/C result in waste form products with greater than 97% of theoretical density. Hot isostatic pressing has recently been implemented as a processing alternative. Characterization of waste-form mineralogy has been done by means of XRD, SEM, and electron microprobe. Leaching of SYNROC D samples is currently being carried out. Assessment of radiation damage effects and physical properties of SYNROC D will commence in FY 81.

  10. Characterization and application of electrospun alumina nanofibers

    PubMed Central

    2014-01-01

    Alumina nanofibers were prepared by a technique that combined the sol–gel and electrospinning methods. The solution to be electrospun was prepared by mixing aluminum isopropoxide (AIP) in ethanol, which was then refluxed in the presence of an acid catalyst and polyvinylpyrolidone (PVP) in ethanol. The characterization results showed that alumina nanofibers with diameters in the range of 102 to 378 nm were successfully prepared. On the basis of the results of the XRD and FT-IR, the alumina nanofibers calcined at 1,100°C were identified as comprising the α-alumina phase, and a series of phase transitions such as boehmite → γ-alumina → α-alumina were observed from 500°C to 1,200°C. The pore size of the obtained γ-alumina nanofibers is approximately 8 nm, and it means that they are mesoporous materials. The kinetic study demonstrated that MO adsorption on alumina nanofibers can be seen that the pseudo-second-order kinetic model fits better than the pseudo-first-order kinetic model. PMID:24467944

  11. Monitoring Transport Across Modified Nanoporous Alumina Membranes

    PubMed Central

    Penumetcha, Sai S.; Kona, Ravikanth; Hardin, Jonathan L.; Molder, Andrew L.; Steinle, Erich D.

    2007-01-01

    This paper describes the use of several characterization methods to examine alumina nanotubule membranes that have been modified with specific silanes. The function of these silanes is to alter the transport properties through the membrane by changing the local environment inside the alumina nanotube. The presence of alkyl groups, either long (C18) or short and branched (isopropyl) hydrocarbon chains, on these silanes significantly decreases the rate of transport of permeant molecules through membranes containing alumina nanotubes as monitored via absorbance spectroscopy. The presence of an ionic surfactant can alter the polarity of these modified nanotubes, which correlates to an increased transport of ions. Fluorescent spectroscopy is also utilized to enhance the sensitivity of detecting these permeant molecules. Confirmation of the alkylsilane attachment to the alumina membrane is achieved with traditional infrared spectroscopy, which can also examine the lifetime of the modified membrane. The physical parameters of these silane-modified porous alumina membranes are studied via scanning electron microscopy. The alumina nanotubes are not physically closed off or capped by the silanes that are attached to the alumina surfaces.

  12. Laser carbonitriding of alumina surface

    NASA Astrophysics Data System (ADS)

    Yilbas, B. S.; Akhtar, S. S.; Karatas, C.

    2011-03-01

    Laser carbonitriding of alumina surfaces is examined. Temperature and stress fields developed during the laser heating of the substrate surface are predicted using the finite element method in line with the experimental conditions. The formation of Al(C, N) and AlN compounds in the surface region of irradiated workpiece is examined using X-ray Photoelectron Spectroscopy (XPS) and X-ray Diffraction (XRD). The microstructural and morphological changes in the laser irradiated region are examined using Scanning Electron Microscope (SEM). The microhardness of the resulting surface is measured and compared with the base material hardness. It is found that high temperature gradient is developed in the irradiated region, which in turn, results in high residual stress levels in this region. XPS and XRD data reveal the presence of Al (C, N) and AlN compounds in the surface region. The microhardness in the surface region of the laser treated workpiece increases significantly.

  13. Alumina forming iron base superalloy

    SciTech Connect

    Yamamoto, Yukinori; Muralidharan, Govindarajan; Brady, Michael P.

    2014-08-26

    An austenitic stainless steel alloy, consists essentially of, in weight percent 2.5 to 4 Al; 25 to 35 Ni; 12 to 19 Cr; at least 1, up to 4 total of at least one element selected from the group consisting of Nb and Ta; 0.5 to 3 Ti; less than 0.5 V; 0.1 to 1 of at least on element selected from the group consisting of Zr and Hf; 0.03 to 0.2 C; 0.005 to 0.1 B; and base Fe. The weight percent Fe is greater than the weight percent Ni. The alloy forms an external continuous scale including alumina, and contains coherent precipitates of .gamma.'-Ni.sub.3Al, and a stable essentially single phase FCC austenitic matrix microstructure. The austenitic matrix is essentially delta-ferrite-free and essentially BCC-phase-free.

  14. Fabrication of thin layer beta alumina

    NASA Technical Reports Server (NTRS)

    Tennenhouse, G. J.

    1977-01-01

    Beta alumina tubes having walls 700 microns, 300 microns, and 140 microns were processed by extrusion and sintering utilizing Ford proprietary binder and fabrication systems. Tubes prepared by this method have properties similar to tubes prepared by isostatic pressing and sintering, i.e. density greater than 98% of theoretical and a helium leak rate less than 3 x 10 to the -9th power cc/sq cm/sec. Ford ultrasonic bonding techniques were used for bonding beta alumina end caps to open ended beta -alumina tubes prior to sintering. After sintering, the bond was hermetic, and the integrity of the bonded area was comparable to the body of the tube.

  15. Design and performance of atomizing nozzles for spray calcination of high-level wastes

    SciTech Connect

    Miller, F.A.; Stout, L.A.

    1981-05-01

    A key aspect of high-level liquid-waste spray calcination is waste-feed atomization by using air atomizing nozzles. Atomization substantially increases the heat transfer area of the waste solution, which enhances rapid drying. Experience from the spray-calciner operations has demonstrated that nozzle flow conditions that produce 70-..mu.. median-volume-diameter or smaller spray droplets are required for small-scale spray calciners (drying capacity less than 80 L/h). For large-scale calciners (drying capacity greater than 300 L/h), nozzle flow conditions that produce 100-..mu.. median-volume-diameter or smaller spray droplets are required. Mass flow ratios of 0.2 to 0.4, depending on nozzle size, are required for proper operation of internal-mix atomizing nozzles. Both internal-mix and external-mix nozzles have been tested at PNL. Due to the lower airflow requirements and fewer large droplets produced, the internal-mix nozzle has been chosen for primary development in the spray calciner program at PNL. Several nozzle air-cap materials for internal-mix nozzles have been tested for wear resistance. Results show that nozzle air caps of stainless steel and Cer-vit (a machineable glass ceramic) are suceptible to rapid wear by abrasive slurries, whereas air caps of alumina and reaction-bonded silicon nitride show only slow wear. Longer-term testing is necessary to determine more accurately the actual frequency of nozzle replacement. Atomizing nozzle air caps of alumina are subject to fracture from thermal shock, whereas air caps of silicon nitride and Cer-vit are not. Fractured nozzles are held in place by the air-cap retaining ring and continue to atomize satisfactorily. Therefore, fractures caused by thermal shocking do not necessarily result in nozzle failure.

  16. The radiation characteristics of the transport packages with vitrified high-level waste

    SciTech Connect

    Bogatov, S. A.; Mitenkova, E. F. Novikov, N. V.

    2015-12-15

    The calculation method of neutron yield in the (α, n) reaction for a homogeneous material of arbitrary composition is represented. It is shown that the use of the ORIGEN 2 code excluding the real elemental composition of vitrified high-level waste leads to significant underestimation of the neutron yield in the (α, n) reaction. For vitrified high-level waste and spent nuclear fuel from VVER, the neutron fluxes are analyzed. The thickness of the protective materials for a transfer cask and a shipping cask with vitrified highlevel waste are estimated.

  17. The radiation characteristics of the transport packages with vitrified high-level waste

    NASA Astrophysics Data System (ADS)

    Bogatov, S. A.; Mitenkova, E. F.; Novikov, N. V.

    2015-12-01

    The calculation method of neutron yield in the (α, n) reaction for a homogeneous material of arbitrary composition is represented. It is shown that the use of the ORIGEN 2 code excluding the real elemental composition of vitrified high-level waste leads to significant underestimation of the neutron yield in the (α, n) reaction. For vitrified high-level waste and spent nuclear fuel from VVER, the neutron fluxes are analyzed. The thickness of the protective materials for a transfer cask and a shipping cask with vitrified highlevel waste are estimated.

  18. Defense High Level Waste Disposal Container System Description

    SciTech Connect

    2000-10-12

    The Defense High Level Waste Disposal Container System supports the confinement and isolation of waste within the Engineered Barrier System of the Monitored Geologic Repository (MGR). Disposal containers are loaded and sealed in the surface waste handling facilities, transferred to the underground through the accesses using a rail mounted transporter, and emplaced in emplacement drifts. The defense high level waste (HLW) disposal container provides long-term confinement of the commercial HLW and defense HLW (including immobilized plutonium waste forms (IPWF)) placed within disposable canisters, and withstands the loading, transfer, emplacement, and retrieval loads and environments. U.S. Department of Energy (DOE)-owned spent nuclear fuel (SNF) in disposable canisters may also be placed in a defense HLW disposal container along with commercial HLW waste forms, which is known as 'co-disposal'. The Defense High Level Waste Disposal Container System provides containment of waste for a designated period of time, and limits radionuclide release. The disposal container/waste package maintains the waste in a designated configuration, withstands maximum handling and rockfall loads, limits the individual canister temperatures after emplacement, resists corrosion in the expected handling and repository environments, and provides containment of waste in the event of an accident. Defense HLW disposal containers for HLW disposal will hold up to five HLW canisters. Defense HLW disposal containers for co-disposal will hold up to five HLW canisters arranged in a ring and one DOE SNF canister in the ring. Defense HLW disposal containers also will hold two Multi-Canister Overpacks (MCOs) and two HLW canisters in one disposal container. The disposal container will include outer and inner cylinders, outer and inner cylinder lids, and may include a canister guide. An exterior label will provide a means by which to identify the disposal container and its contents. Different materials

  19. The structure-directed effect of Al-based metal–organic frameworks on fabrication of alumina by thermal treatment

    SciTech Connect

    Liu, Dandan; Dai, Fangna; Tang, Zhe; Liu, Yunqi; Liu, Chenguang

    2015-05-15

    Highlights: • We use Al-MOFs as precursor in the fabrication process of mesoporous alumina by thermal treatment. • The obtained mesoporous alumina has dual pore system and five-fold aluminum. • The aluminum building units in the precursor show structure-directed effect on the formation of alumina. - Abstract: In this work, the block-shaped Al-based metal–organic frameworks (Al-MOFs) MIL-53 have been synthesized by hydrothermal method. To detect the correlation between the structure of Al-MOFs and the formation of alumina, the ligands are eliminated by thermal treatment. MIL-53 and the calcination products were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM), transmission electron microscopy (TEM), nitrogen adsorption–desorption and solid-state {sup 27}Al nuclear magnetic resonance ({sup 27}Al NMR). It was found that after calcination, the block-shaped Al-MOFs precursor turns into high-crystallinity mesoporous alumina nanosheets, and the thermal treatment product γ-alumina possesses a dual pore system and a large surface area (146 m{sup 2}/g), with five-fold aluminum. During the thermal treatment process, the structure of MIL-53 and its secondary building units have structure-directed effect in the formation of alumina.

  20. 40 CFR 227.30 - High-level radioactive waste.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 25 2011-07-01 2011-07-01 false High-level radioactive waste. 227.30 Section 227.30 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING...-level radioactive waste. High-level radioactive waste means the aqueous waste resulting from...

  1. 40 CFR 227.30 - High-level radioactive waste.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 25 2014-07-01 2014-07-01 false High-level radioactive waste. 227.30 Section 227.30 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING...-level radioactive waste. High-level radioactive waste means the aqueous waste resulting from...

  2. 40 CFR 227.30 - High-level radioactive waste.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 26 2012-07-01 2011-07-01 true High-level radioactive waste. 227.30 Section 227.30 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING...-level radioactive waste. High-level radioactive waste means the aqueous waste resulting from...

  3. 40 CFR 227.30 - High-level radioactive waste.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 26 2013-07-01 2013-07-01 false High-level radioactive waste. 227.30 Section 227.30 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING...-level radioactive waste. High-level radioactive waste means the aqueous waste resulting from...

  4. 46 CFR 182.530 - Bilge high level alarms.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Bilge high level alarms. 182.530 Section 182.530... TONS) MACHINERY INSTALLATION Bilge and Ballast Systems § 182.530 Bilge high level alarms. (a) On a... operating station to indicate a high water level in each of the following normally unmanned spaces: (1)...

  5. 46 CFR 182.530 - Bilge high level alarms.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Bilge high level alarms. 182.530 Section 182.530... TONS) MACHINERY INSTALLATION Bilge and Ballast Systems § 182.530 Bilge high level alarms. (a) On a... operating station to indicate a high water level in each of the following normally unmanned spaces: (1)...

  6. 46 CFR 119.530 - Bilge high level alarms.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Bilge high level alarms. 119.530 Section 119.530... Bilge and Ballast Systems § 119.530 Bilge high level alarms. (a) Each vessel must be provided with a visual and audible alarm at the operating station to indicate a high water level in each of the...

  7. 46 CFR 119.530 - Bilge high level alarms.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Bilge high level alarms. 119.530 Section 119.530... Bilge and Ballast Systems § 119.530 Bilge high level alarms. (a) Each vessel must be provided with a visual and audible alarm at the operating station to indicate a high water level in each of the...

  8. 46 CFR 182.530 - Bilge high level alarms.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Bilge high level alarms. 182.530 Section 182.530... TONS) MACHINERY INSTALLATION Bilge and Ballast Systems § 182.530 Bilge high level alarms. (a) On a... operating station to indicate a high water level in each of the following normally unmanned spaces: (1)...

  9. 46 CFR 182.530 - Bilge high level alarms.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Bilge high level alarms. 182.530 Section 182.530... TONS) MACHINERY INSTALLATION Bilge and Ballast Systems § 182.530 Bilge high level alarms. (a) On a... operating station to indicate a high water level in each of the following normally unmanned spaces: (1)...

  10. 46 CFR 119.530 - Bilge high level alarms.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Bilge high level alarms. 119.530 Section 119.530... Bilge and Ballast Systems § 119.530 Bilge high level alarms. (a) Each vessel must be provided with a visual and audible alarm at the operating station to indicate a high water level in each of the...

  11. 46 CFR 119.530 - Bilge high level alarms.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Bilge high level alarms. 119.530 Section 119.530... Bilge and Ballast Systems § 119.530 Bilge high level alarms. (a) Each vessel must be provided with a visual and audible alarm at the operating station to indicate a high water level in each of the...

  12. 46 CFR 119.530 - Bilge high level alarms.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Bilge high level alarms. 119.530 Section 119.530... Bilge and Ballast Systems § 119.530 Bilge high level alarms. (a) Each vessel must be provided with a visual and audible alarm at the operating station to indicate a high water level in each of the...

  13. 46 CFR 153.409 - High level alarms.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false High level alarms. 153.409 Section 153.409 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SHIPS CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Cargo Gauging Systems § 153.409 High level alarms. When Table...

  14. Corrosion Behaviour of Sputtered Alumina Thin Films

    NASA Astrophysics Data System (ADS)

    Reddy, I. Neelakanta; Dey, Arjun; Sridhara, N.; Anoop, S.; Bera, Parthasarathi; Rani, R. Uma; Anandan, Chinnasamy; Sharma, Anand Kumar

    2015-10-01

    Corrosion studies of sputtered alumina thin films grown on stainless steel (SS) 304 were carried out by linear polarization and electrochemical impedance spectroscopy. Noticeable changes were not observed in morphology and surface roughness of films after carrying out the corrosion test. Corrosion current density (icorr) of alumina coated SS decreased up to 10-10 A cm-2 while icorr value in the range of 10-5-10-6 A cm-2 was observed for bare SS. The direct sputtered film showed superior corrosion resistance behaviour than the reactive sputtered film. This might be attributed to the difference in thickness of the films sputtered by direct and reactive methods. The electronic structure of deposited alumina films was studied both before and after corrosion test by X-ray photoelectron spectroscopy technique which also confirmed no structural changes of alumina film after exposing it to corrosive environment.

  15. Loss tangent measurements on unirradiated alumina

    SciTech Connect

    Zinkle, S.J.; Goulding, R.H.

    1996-04-01

    Unirradiated room temperature loss tangent for sapphire and several commercial grades of polycrystalline alumina are complied for frequencies between 10{sup 5} and 4x10{sup 11} Hz. Sapphire exhibits significantly lower values for the loss tangent at frequencies up to 10{sup 11} Hz. The loss tangents of 3 different grades of Wesgo alumina (AL300, AL995, AL998) and 2 different grades of Coors alumina (AD94, AD995) have typical values near {approx}10{sup -4} at a frequency of 10{sup 8} Hz. On the other hand, the loss tangent of Vitox alumina exhibits a large loss peak tan d{approx} 5x10{sup -3} at this frequency.

  16. Processing of Alumina-Toughened Zirconia Composites

    NASA Technical Reports Server (NTRS)

    Bansal, Narottam P.; Choi, Sung R.

    2003-01-01

    Dense and crack-free 10-mol%-yttria-stabilized zirconia (10YSZ)-alumina composites, containing 0 to 30 mol% of alumina, have been fabricated by hot pressing. Release of pressure before onset of cooling was crucial in obtaining crack-free material. Hot pressing at 1600 C resulted in the formation of ZrC by reaction of zirconia with grafoil. However, no such reaction was observed at 1500 C. Cubic zirconia and -alumina were the only phases detected from x-ray diffraction indicating no chemical reaction between the composite constituents during hot pressing. Microstructure of the composites was analyzed by scanning electron microscopy and transmission electron microscopy. Density and elastic modulus of the composites followed the rule-of-mixtures. Addition of alumina to 10YSZ resulted in lighter, stronger, and stiffer composites by decreasing density and increasing strength and elastic modulus.

  17. PLUTONIUM/HIGH-LEVEL VITRIFIED WASTE BDBE DOSE CALCULATION

    SciTech Connect

    D.C. Richardson

    2003-03-19

    In accordance with the Nuclear Waste Policy Amendments Act of 1987, Yucca Mountain was designated as the site to be investigated as a potential repository for the disposal of high-level radioactive waste. The Yucca Mountain site is an undeveloped area located on the southwestern edge of the Nevada Test Site (NTS), about 100 miles northwest of Las Vegas. The site currently lacks rail service or an existing right-of-way. If the Yucca Mountain site is found suitable for the repository, rail service is desirable to the Office of Civilian Waste Management (OCRWM) Program because of the potential of rail transportation to reduce costs and to reduce the number of shipments relative to highway transportation. A Preliminary Rail Access Study evaluated 13 potential rail spur options. Alternative routes within the major options were also developed. Each of these options was then evaluated for potential land use conflicts and access to regional rail carriers. Three potential routes having few land use conflicts and having access to regional carriers were recommended for further investigation. Figure 1-1 shows these three routes. The Jean route is estimated to be about 120 miles long, the Carlin route to be about 365 miles long, and Caliente route to be about 365 miles long. The remaining ten routes continue to be monitored and should any of the present conflicts change, a re-evaluation of that route will be made. Complete details of the evaluation of the 13 routes can be found in the previous study. The DOE has not identified any preferred route and recognizes that the transportation issues need a full and open treatment under the National Environmental Policy Act. The issue of transportation will be included in public hearings to support development of the Environmental Impact Statement (EIS) proceedings for either the Monitored Retrievable Storage Facility or the Yucca Mountain Project or both.

  18. High-Level Waste Systems Plan. Revision 7

    SciTech Connect

    Brooke, J.N.; Gregory, M.V.; Paul, P.; Taylor, G.; Wise, F.E.; Davis, N.R.; Wells, M.N.

    1996-10-01

    This revision of the High-Level Waste (HLW) System Plan aligns SRS HLW program planning with the DOE Savannah River (DOE-SR) Ten Year Plan (QC-96-0005, Draft 8/6), which was issued in July 1996. The objective of the Ten Year Plan is to complete cleanup at most nuclear sites within the next ten years. The two key principles of the Ten Year Plan are to accelerate the reduction of the most urgent risks to human health and the environment and to reduce mortgage costs. Accordingly, this System Plan describes the HLW program that will remove HLW from all 24 old-style tanks, and close 20 of those tanks, by 2006 with vitrification of all HLW by 2018. To achieve these goals, the DWPF canister production rate is projected to climb to 300 canisters per year starting in FY06, and remain at that rate through the end of the program in FY18, (Compare that to past System Plans, in which DWPF production peaked at 200 canisters per year, and the program did not complete until 2026.) An additional $247M (FY98 dollars) must be made available as requested over the ten year planning period, including a one-time $10M to enhance Late Wash attainment. If appropriate resources are made available, facility attainment issues are resolved and regulatory support is sufficient, then completion of the HLW program in 2018 would achieve a $3.3 billion cost savings to DOE, versus the cost of completing the program in 2026. Facility status information is current as of October 31, 1996.

  19. Studies of Plasma-Sprayed Alumina

    NASA Astrophysics Data System (ADS)

    Ilavsky, Jan

    1994-05-01

    Phase transformations and porosity of the plasma sprayed alumina deposits were examined. The dependence of the phase transformations on deposit chemistry was established. Porosity changes during heat treatment were studied and a model for the porosity is proposed. A novel technique in the field of plasma sprayed deposits--small-angle neutron scattering (SANS)--was successfully applied. Deposits were manufactured using the water-stabilized plasma spray system, PAL160, with an input of 160 kW. Phase transformations of the plasma sprayed alumina deposits were studied using XRD and DTA. The deposits were manufactured from 99.9% alumina, alumina-chromia (1.5% Cr_2O_3), gray alumina (3.7% TiO_2) and alumina -titania (17% TiO_2). The addition of chromia increases the temperature of the alpha phase formation by about 40^circ C and the addition of TiO_2 reduces this temperature by about 150^circ C for gray alumina and by about 175^ circC for alumina-titania. The amount of metastable theta phase was found to depend on the chemistry of the feedstock. Porosities of the deposits, made from alumina and gray alumina, were studied using mercury intrusion porosimetry, weighing method (Archimedean porosimetry), image analysis and SANS. Samples were studied in the as -sprayed condition and after heat treatment for 2 hours at 1300^circC and 1500 ^circC. Porosity depends on the deposit chemistry and on the heat treatment and varies from 5% to about 11%. Different porosity measurement techniques yield different results. Surface areas of 1.5 to 7.5 times 10^4 cm^2 /cm^3 (times 10^6 m^{ -1}) were measured using SANS and depend on heat treatment and on the deposit chemistry. The phase transformations can be associated with an increase in pore surface area and decrease in surface area at 1500 ^circC can be associated with sintering. The effective pore radius, R_{ rm eff}, as measured by SANS is a measure of the pore sizes in the 0.08 to 10 μm size range. The R_{rm eff} depends on deposit

  20. Preparation and Characterization of Electrospun Alumina Nanofibers

    NASA Astrophysics Data System (ADS)

    Pinti, Marie J.; Tacastacas, Stephen N.; Stojilovic, Nenad; O'Brien, John P.; Pischera, Anna; Espe, Matthew P.

    2008-10-01

    Alumina nanofibers are promising materials for use in high- temperature applications since they are chemically inert up to very high temperatures. Applications include use as catalyst support in high-temperature chemical reactions, fire protection materials, and as a high-temperature insulator. Electrospinning is a relatively simple and inexpensive method for obtaining nanometer-size fibers and has become a popular technique for producing metal-oxide nanofibers in recent years. The electrospinning mixture for the production of alumina nanofibers typically contains aluminum acetate stabilized with boric acid as the alumina precursor; but the observed presence of boron and sodium on the surface of these nanofibers may affect their use as catalytic supports. We have produced alumina nanofibers from an aluminum reagent devoid of the boric acid stabilizer and calcined the fibers at different temperatures to produce nanofibers with different phases of alumina. Characterization of the fibers by TGA, FE-SEM equipped with the XEDS, powder XRD, DRIFTS, and SSNMR methods to determine the fate of the precursors, fiber morphology and the composition and structure of the calcined alumina nanofibers.

  1. New support for high-performance liquid chromatography based on silica coated with alumina particles.

    PubMed

    Silveira, José Leandro R; Dib, Samia R; Faria, Anizio M

    2014-01-01

    A new material based on silica coated with alumina nanoparticles was proposed for use as a chromatographic support for reversed-phase high-performance liquid chromatography. Alumina nanoparticles were synthesized by a sol-gel process in reversed micelles composed of sodium bis(2-ethylhexyl)sulfosuccinate, and the support material was formed by the self-assembly of alumina layers on silica spheres. Spectroscopic and (29)Si nuclear magnetic resonance results showed evidence of chemical bonds between the alumina nanoparticles and the silica spheres, while morphological characterizations showed that the aluminized silica maintained the morphological properties of silica desired for chromatographic purposes after alumina incorporation. Stability studies indicated that bare silica showed high dissolution (~83%), while the aluminized silica remained practically unchanged (99%) after passing one liter of the alkaline mobile phase, indicating high stability under alkaline conditions. The C18 bonded aluminized silica phase showed great potential for use in high-performance liquid chromatography to separate basic molecules in the reversed-phase mode. PMID:24521917

  2. Neptunium estimation in dissolver and high-level-waste solutions

    SciTech Connect

    Pathak, P.N.; Prabhu, D.R.; Kanekar, A.S.; Manchanda, V.K.

    2008-07-01

    This papers deals with the optimization of the experimental conditions for the estimation of {sup 237}Np in spent-fuel dissolver/high-level waste solutions using thenoyltrifluoroacetone as the extractant. (authors)

  3. HIGH-LEVEL OZONE DISINFECTION OF MUNICIPAL WASTEWATER EFFLUENTS

    EPA Science Inventory

    A 20 month operating experimental program was conducted at Marlborough, Massachusetts to evaluate the feasibility, engineering, and economic aspects of achieving high levels of effluent disinfection with ozone. The ozone research pilot facility was designed to operate at a consta...

  4. West Valley demonstration project: alternative processes for solidifying the high-level wastes

    SciTech Connect

    Holton, L.K.; Larson, D.E.; Partain, W.L.; Treat, R.L.

    1981-10-01

    In 1980, the US Department of Energy (DOE) established the West Valley Solidification Project as the result of legislation passed by the US Congress. The purpose of this project was to carry out a high level nuclear waste management demonstration project at the Western New York Nuclear Service Center in West Valley, New York. The DOE authorized the Pacific Northwest Laboratory (PNL), which is operated by Battelle Memorial Institute, to assess alternative processes for treatment and solidification of the WNYNSC high-level wastes. The Process Alternatives Study is the suject of this report. Two pretreatment approaches and several waste form processes were selected for evaluation in this study. The two waste treatment approaches were the salt/sludge separation process and the combined waste process. Both terminal and interim waste form processes were studied.

  5. Decision Document for Heat Removal from High Level Waste Tanks

    SciTech Connect

    WILLIS, W.L.

    2000-07-31

    This document establishes the combination of design and operational configurations that will be used to provide heat removal from high-level waste tanks during Phase 1 waste feed delivery to prevent the waste temperature from exceeding tank safety requirement limits. The chosen method--to use the primary and annulus ventilation systems to remove heat from the high-level waste tanks--is documented herein.

  6. 46 CFR 182.530 - Bilge high level alarms.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Bilge high level alarms. 182.530 Section 182.530 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS (UNDER 100 GROSS TONS) MACHINERY INSTALLATION Bilge and Ballast Systems § 182.530 Bilge high level alarms. (a) On a vessel of at least 7.9 meters (26 feet) in...

  7. High-Level Waste System Process Interface Description

    SciTech Connect

    d'Entremont, P.D.

    1999-01-14

    The High-Level Waste System is a set of six different processes interconnected by pipelines. These processes function as one large treatment plant that receives, stores, and treats high-level wastes from various generators at SRS and converts them into forms suitable for final disposal. The three major forms are borosilicate glass, which will be eventually disposed of in a Federal Repository, Saltstone to be buried on site, and treated water effluent that is released to the environment.

  8. Modeling Lewis acidity of transition aluminas by numerical simulations

    SciTech Connect

    Alvarez, L.J.; Blumenfeld, A.L.; Fripiat, J.J.

    1998-01-01

    The bulk and surface features of an alumina particle obtained by molecular-dynamics simulation are used to support the experimental distribution of aluminums with respect to their coordination number obtained by NMR (nuclear magnetic resonance). This information was obtained by using results of various editing procedures of the {sup 27}Al nuclear magnetic resonance, such as the classical one-pulse (1P) magic angle spinning, the cross polarization (CP) from the protons of chemisorbed ammonia and the 1P or CP rotational echo double resonance (REDOR). Because the REDOR technique revealed that the acid Lewis sites are constituted by pairs of four or fivefold coordinated aluminum atoms about 3 {Angstrom} apart, these pairs were counted in the simulated particle. The agreement with experimental surface density of Lewis sites is satisfactory. {copyright} {ital 1998 American Institute of Physics.}

  9. Thirty years of experience with alumina-on-alumina bearings in total hip arthroplasty.

    PubMed

    Hannouche, Didier; Zaoui, Amine; Zadegan, Frédéric; Sedel, Laurent; Nizard, Rémy

    2011-02-01

    Alumina-on-alumina bearings in total hip arthroplasty have been developed in an attempt to minimise debris and the occurrence of osteolytic lesions. The outstanding tribological properties of this bearing system are explained by low surface roughness, high hardness for major scratch resistance, and high wettability. Since the 1970s, technological improvements in the manufacturing process of alumina components together with a better understanding of Morse taper technology have provided a surgical grade material with high density, high purity and small grains. Published studies on the outcome of total hip arthroplasty performed with this new generation of implants showed high survivorship especially in young and active patients, with survival rates free of revision of 90.8% to 97.4% at ten years. However, concern remains over ceramic liner fracture and squeaking, which has been noted recently with increasing prevalence. This review will discuss the current knowledge on the use of alumina-on-alumina bearings. PMID:21191579

  10. Thirty years of experience with alumina-on-alumina bearings in total hip arthroplasty

    PubMed Central

    Zaoui, Amine; Zadegan, Frédéric; Sedel, Laurent; Nizard, Rémy

    2010-01-01

    Alumina-on-alumina bearings in total hip arthroplasty have been developed in an attempt to minimise debris and the occurrence of osteolytic lesions. The outstanding tribological properties of this bearing system are explained by low surface roughness, high hardness for major scratch resistance, and high wettability. Since the 1970s, technological improvements in the manufacturing process of alumina components together with a better understanding of Morse taper technology have provided a surgical grade material with high density, high purity and small grains. Published studies on the outcome of total hip arthroplasty performed with this new generation of implants showed high survivorship especially in young and active patients, with survival rates free of revision of 90.8% to 97.4% at ten years. However, concern remains over ceramic liner fracture and squeaking, which has been noted recently with increasing prevalence. This review will discuss the current knowledge on the use of alumina-on-alumina bearings. PMID:21191579

  11. SETTLING OF SPINEL IN A HIGH-LEVEL WASTE GLASS MELTER

    SciTech Connect

    Pavel Hrma; Pert Schill; Lubomir Nemec

    2002-01-07

    High-level nuclear waste is being vitrified, i.e., converted to a durable glass that can be stored in a safe repository for hundreds of thousands of years. Waste vitrification is accomplished in reactors called melters to which the waste is charged together with glass-forming additives. The mixture is electrically heated to a temperature as high as 1150 decrees C to create a melt that becomes glass on cooling.

  12. Criticality Safety Evaluation of Hanford Site High Level Waste Storage Tanks

    SciTech Connect

    ROGERS, C.A.

    2000-02-17

    This criticality safety evaluation covers operations for waste in underground storage tanks at the high-level waste tank farms on the Hanford site. This evaluation provides the bases for criticality safety limits and controls to govern receipt, transfer, and long-term storage of tank waste. Justification is provided that a nuclear criticality accident cannot occur for tank farms operations, based on current fissile material and operating conditions.

  13. Robotic systems for the high level waste tank farm replacement project at INEL

    SciTech Connect

    Berger, A.; White, D.; Thompson, B.; Christensen, M.

    1993-06-01

    Westinghouse Idaho Nuclear Company (WINCO) is specifying and designing a new high level waste tank farm at the Idaho National Engineering Laboratory (INEL). The farm consists of four underground storage tanks, which replace the existing tanks. The new facility includes provisions for remote operations. One of the planned remote operations is robotic inspection of the tank from the interior and exterior. This paper describes the process used to design the robotic system for the inspection tasks.

  14. High level waste interim storge architecture selection - decision report

    SciTech Connect

    Calmus, R.B.

    1996-09-27

    The U.S. Department of Energy (DOE) has embarked upon a course to acquire Hanford Site tank waste treatment and immobilization services using privatized facilities (RL 1996a). This plan contains a two-phased approach. Phase I is a proof-of-principle/connnercial demonstration- scale effort and Phase II is a fiill-scale production effort. In accordance with the planned approach, interim storage and disposal of various products from privatized facilities are to be DOE fumished. The high-level waste (BLW) interim storage options, or alternative architectures, were identified and evaluated to provide the framework from which to select the most viable method of Phase I BLW interim storage (Calmus 1996). This evaluation, hereafter referred to as the Alternative Architecture Evaluation, was performed to established performance and risk criteria (technical merit, cost, schedule, etc.). Based on evaluation results, preliminary architectures and path forward reconunendations were provided for consideration in the architecture decision- maldng process. The decision-making process used for selection of a Phase I solidified BLW interim storage architecture was conducted in accordance with an approved Decision Plan (see the attachment). This decision process was based on TSEP-07,Decision Management Procedure (WHC 1995). The established decision process entailed a Decision Board, consisting of Westinghouse Hanford Company (VY`HC) management staff, and included appointment of a VTHC Decision Maker. The Alternative Architecture Evaluation results and preliminary recommendations were presented to the Decision Board members for their consideration in the decision-making process. The Alternative Architecture Evaluation was prepared and issued before issuance of @C-IP- 123 1, Alternatives Generation and Analysis Procedure (WI-IC 1996a), but was deemed by the Board to fully meet the intent of WHC-IP-1231. The Decision Board members concurred with the bulk of the Alternative Architecture

  15. An analytical hierarchy process for decision making of high-level-waste management

    SciTech Connect

    Wang, J.H.C.; Jang, W.

    1995-12-01

    To prove the existence value of nuclear technology for the world of post cold war, demonstration of safe rad-waste disposal is essential. High-level-waste (HLW) certainly is the key issue to be resolved. To assist a rational and persuasive process on various disposal options, an Analytical Hierarchy Process (AHP) for the decision making of HLW management is presented. The basic theory and rationale are discussed, and applications are shown to illustrate the usefulness of the AHP. The authors wish that the AHP can provide a better direction for the current doomed situations of Taiwan nuclear industry, and to exchange with other countries for sharing experiences on the HLW management.

  16. Dielectric Performance of a High Purity HTCC Alumina at High Temperatures - a Comparison Study with Other Polycrystalline Alumina

    NASA Technical Reports Server (NTRS)

    Chen, Liangyu

    2014-01-01

    A very high purity (99.99+%) high temperature co-fired ceramic (HTCC) alumina has recently become commercially available. The raw material of this HTCC alumina is very different from conventional HTCC alumina, and more importantly there is no glass additive in this alumina material for co-firing processing. Previously, selected HTCC and LTCC (low temperature co-fired ceramic) alumina materials were evaluated at high temperatures as dielectric and compared to a regularly sintered 96% polycrystalline alumina (96% Al2O3), where 96% alumina was used as the benchmark. A prototype packaging system based on regular 96% alumina with Au thickfilm metallization successfully facilitated long term testing of high temperature silicon carbide (SiC) electronic devices for over 10,000 hours at 500 C. In order to evaluate this new high purity HTCC alumina for possible high temperature packaging applications, the dielectric properties of this HTCC alumina substrate were measured and compared with those of 96% alumina and a previously tested LTCC alumina from room temperature to 550 C at frequencies of 120 Hz, 1 KHz, 10 KHz, 100 KHz, and 1 MHz. A parallel-plate capacitive device with dielectric of the HTCC alumina and precious metal electrodes were used for measurements of the dielectric constant and dielectric loss of the co-fired alumina material in the temperature and frequency ranges. The capacitance and AC parallel conductance of the capacitive device were directly measured by an AC impedance meter, and the dielectric constant and parallel AC conductivity of the dielectric were calculated from the capacitance and conductance measurement results. The temperature and frequency dependent dielectric constant, AC conductivity, and dissipation factor of the HTCC alumina substrate are presented and compared to those of 96% alumina and a selected LTCC alumina. Other technical advantages of this new co-fired material for possible high packaging applications are also discussed.

  17. Long-term results of alumina-on-alumina hip arthroplasty for osteonecrosis.

    PubMed

    Nich, Christophe; Sariali, El-Hadi; Sari Ali, El-Hadi; Hannouche, Didier; Nizard, Rémy; Witvoet, Jacques; Sedel, Laurent; Bizot, Pascal

    2003-12-01

    Alumina-on-alumina bearings in THR may, in theory, provide an effective answer to osteolysis in young patients with ON of the femoral head. The purpose of this retrospective study was to report the long-term results of a series of 52 consecutive alumina THAs (41 patients) done for ON. The mean age of the patients at surgery was 41 years (range, 22-79 years). Cemented femoral stems with a 32-mm alumina head were used. Plain alumina cups were used and were either cemented (39 hips) or press-fit (13 hips). No patients were lost to followup. Sixteen hips have been revised. Aseptic loosening of the socket was the main cause of failure. At an average 16-year followup (range, 11-23.65 years), 26 hips were rated excellent and one hip was rated good. No osteolysis was observed and wear was undetectable. If revision for aseptic loosening was the end point, the rate of survival was 88.5% at 10 years for the socket and 100% at 10 years for the stem. With the alumina-on-alumina hip replacement done for ON, absence of osteolysis can be expected for as many as 24 years after the operation. New methods of socket fixation now are being explored. PMID:14646707

  18. An overview of very high level software design methods

    NASA Technical Reports Server (NTRS)

    Asdjodi, Maryam; Hooper, James W.

    1988-01-01

    Very High Level design methods emphasize automatic transfer of requirements to formal design specifications, and/or may concentrate on automatic transformation of formal design specifications that include some semantic information of the system into machine executable form. Very high level design methods range from general domain independent methods to approaches implementable for specific applications or domains. Applying AI techniques, abstract programming methods, domain heuristics, software engineering tools, library-based programming and other methods different approaches for higher level software design are being developed. Though one finds that a given approach does not always fall exactly in any specific class, this paper provides a classification for very high level design methods including examples for each class. These methods are analyzed and compared based on their basic approaches, strengths and feasibility for future expansion toward automatic development of software systems.

  19. Optical Basicity and Nepheline Crystallization in High Alumina Glasses

    SciTech Connect

    Rodriguez, Carmen P.; McCloy, John S.; Schweiger, M. J.; Crum, Jarrod V.; Winschell, Abigail E.

    2011-02-25

    The purpose of this study was to find compositions that increase waste loading of high-alumina wastes beyond what is currently acceptable while avoiding crystallization of nepheline (NaAlSiO4) on slow cooling. Nepheline crystallization has been shown to have a large impact on the chemical durability of high-level waste glasses. It was hypothesized that there would be some composition regions where high-alumina would not result in nepheline crystal production, compositions not currently allowed by the nepheline discriminator. Optical basicity (OB) and the nepheline discriminator (ND) are two ways of describing a given complex glass composition. This report presents the theoretical and experimental basis for these models. They are being studied together in a quadrant system as metrics to explore nepheline crystallization and chemical durability as a function of waste glass composition. These metrics were calculated for glasses with existing data and also for theoretical glasses to explore nepheline formation in Quadrant IV (passes OB metric but fails ND metric), where glasses are presumed to have good chemical durability. Several of these compositions were chosen, and glasses were made to fill poorly represented regions in Quadrant IV. To evaluate nepheline formation and chemical durability of these glasses, quantitative X-ray diffraction (XRD) analysis and the Product Consistency Test were conducted. A large amount of quantitative XRD data is collected here, both from new glasses and from glasses of previous studies that had not previously performed quantitative XRD on the phase assemblage. Appendix A critically discusses a large dataset to be considered for future quantitative studies on nepheline formation in glass. Appendix B provides a theoretical justification for choice of the oxide coefficients used to compute the OB criterion for nepheline formation.

  20. Fourier transform infrared photoacoustic spectroscopy of pyridine adsorbed on silica-alumina and. gamma. -alumina

    SciTech Connect

    Riseman, S.M.; Massoth, F.E.; Dhar, G.M.; Eyring, E.M.

    1982-05-13

    Relative numbers of Bronsted acid to Lewis acid sites on silica-alumina have been determined photoacoustically by an infrared analysis of chemisorbed pyridine compared to similar adsorption of ..gamma..-alumina that has only Lewis sites. Results are similar to those obtained by earlier IR transmission studies that suggested the use of framework vibrations of silica as an internal reference standard. The 20% coverage of the silica-alumina surface by pyridine adsorbed at Bronsted sites found photoacoustically is in good agreement with a previous value of 17% estimated from transmission spectroscopic data. Reproducibility of the photoacoustic measurements is excellent.

  1. High Level Waste (HLW) Feed Process Control Strategy

    SciTech Connect

    STAEHR, T.W.

    2000-06-14

    The primary purpose of this document is to describe the overall process control strategy for monitoring and controlling the functions associated with the Phase 1B high-level waste feed delivery. This document provides the basis for process monitoring and control functions and requirements needed throughput the double-shell tank system during Phase 1 high-level waste feed delivery. This document is intended to be used by (1) the developers of the future Process Control Plan and (2) the developers of the monitoring and control system.

  2. Sterilization, high-level disinfection, and environmental cleaning.

    PubMed

    Rutala, William A; Weber, David J

    2011-03-01

    Failure to perform proper disinfection and sterilization of medical devices may lead to introduction of pathogens, resulting in infection. New techniques have been developed for achieving high-level disinfection and adequate environmental cleanliness. This article examines new technologies for sterilization and high-level disinfection of critical and semicritical items, respectively, and because semicritical items carry the greatest risk of infection, the authors discuss reprocessing semicritical items such as endoscopes and automated endoscope reprocessors, endocavitary probes, prostate biopsy probes, tonometers, laryngoscopes, and infrared coagulation devices. In addition, current issues and practices associated with environmental cleaning are reviewed. PMID:21315994

  3. High level radioactive waste management facility design criteria

    SciTech Connect

    Sheikh, N.A.; Salaymeh, S.R.

    1993-10-01

    This paper discusses the engineering systems for the structural design of the Defense Waste Processing Facility (DWPF) at the Savannah River Site (SRS). At the DWPF, high level radioactive liquids will be mixed with glass particles and heated in a melter. This molten glass will then be poured into stainless steel canisters where it will harden. This process will transform the high level waste into a more stable, manageable substance. This paper discuss the structural design requirements for this unique one of a kind facility. A special emphasis will be concentrated on the design criteria pertaining to earthquake, wind and tornado, and flooding.

  4. The Use of ARTEMIS with High-Level Applications

    SciTech Connect

    B. A. Bowling; H. Shoaee; S. Witherspoon

    1995-10-01

    ARTEMIS is an online accelerator modeling server developed at CEBAF. One of the design goals of ARTEMIS was to provide an integrated modeling environment for high- level accelerator diagnostic and control applications such as automated beam steering, Linac Energy management (LEM) and the fast feedback system. This report illustrates the use of ARTEMIS in these applications as well as the application interface using the EPICS cdev device support API. Concentration is placed on the design and implementation aspects of high- level applications which utilize the ARTEMIS server for information on beam dynamics. Performance benchmarks for various model operations provided by ARTEMIS are also discussed.

  5. Final report on cermet high-level waste forms

    SciTech Connect

    Kobisk, E.H.; Quinby, T.C.; Aaron, W.S.

    1981-08-01

    Cermets are being developed as an alternate method for the fixation of defense and commercial high level radioactive waste in a terminal disposal form. Following initial feasibility assessments of this waste form, consisting of ceramic particles dispersed in an iron-nickel base alloy, significantly improved processing methods were developed. The characterization of cermets has continued through property determinations on samples prepared by various methods from a variety of simulated and actual high-level wastes. This report describes the status of development of the cermet waste form as it has evolved since 1977. 6 tables, 18 figures.

  6. Laser Ablation of Alumina in Water

    SciTech Connect

    Musaev, O.; Midgley, A; Wrobel, J; Kruger, M

    2010-01-01

    Bulk {alpha}-alumina immersed in distilled water was ablated by pulsed UV laser radiation. The resulting colloidal solution contained micron and submicron size particles. X-ray diffraction and Raman spectra of the ablated and original material are similar. Hence, most of the ablated material is {alpha}-alumina. From transmission electron microscope images, most of the submicron and all of the micron-sized particles have sharp edges and do not have spherical shapes, indicating that the dominant ablation mechanism is due to crack propagation. Some spherical particles of diameter less than 100 nm are observed, indicating that they were formed from the liquid state.

  7. Chlorination of alumina in kaolinitic clay

    NASA Astrophysics Data System (ADS)

    Grob, B.; Richarz, W.

    1984-09-01

    The chlorination of alumina in kaolinitic clay with Cl2 and CO gas mixtures was studied gravimetrically. The effects of the calcination method and of NaCl addition on the reactivity of the clay were examined. Fast reaction rates were achieved only with samples previously exposed to a sulfating treatment. Optimum conditions, with maximum yield and selectivity to A1C13 and minimum SiO2 conversion, were found between 770 and 970 K. At higher temperatures the SiCl4 formed poisons the reactive alumina surface by selective chemisorption with a marked decrease of the reaction rate.

  8. Nanomechanical humidity detection through porous alumina cantilevers

    PubMed Central

    Klimenko, Alexey; Lebedev, Vasiliy; Lukashin, Alexey; Eliseev, Andrey

    2015-01-01

    Summary We present here the behavior of the resonance frequency of porous anodic alumina cantilever arrays during water vapor adsorption and emphasize their possible use in the micromechanical sensing of humidity levels at least in the range of 10–22%. The sensitivity of porous anodic aluminium oxide cantilevers (Δf/Δm) and the humidity sensitivity equal about 56 Hz/pg and about 100 Hz/%, respectively. The approach presented here for the design of anodic alumina cantilever arrays by the combination of anodic oxidation and photolithography enables easy control over porosity, surface area, geometric and mechanical characteristics of the cantilever arrays for micromechanical sensing. PMID:26199836

  9. Structural transformations in reactively sputtered alumina films

    SciTech Connect

    Nayar, P. Khanna, A.

    2014-04-24

    Thin films of amorphous alumina of thickness ∼350 nm were prepared on silicon wafer by DC cathode reactive sputtering. The effects of thermal annealing on the structural properties were investigated at annealing temperatures of 600°C, 800°C, 1100°C and 1220°C. X-ray diffraction showed that crystallization starts at 800°C and produces δ and θ alumina phases, the latter phase grows with heat treatment and the film was predominantly δ-phase with small amount of a-phase after annealing at 1220°C. AFM studies found that the surface of thin films smoothened upon crystallization.

  10. 40 CFR 721.10120 - Siloxane modified alumina nanoparticles (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Siloxane modified alumina... Specific Chemical Substances § 721.10120 Siloxane modified alumina nanoparticles (generic). (a) Chemical... as siloxane modified alumina nanoparticles (PMN P-05-687) is subject to reporting under this...

  11. 21 CFR 73.1010 - Alumina (dried aluminum hydroxide).

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 1 2013-04-01 2013-04-01 false Alumina (dried aluminum hydroxide). 73.1010... GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1010 Alumina (dried aluminum hydroxide). (a) Identity. (1) The color additive alumina (dried aluminum hydroxide) is a white,...

  12. 21 CFR 73.1010 - Alumina (dried aluminum hydroxide).

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 1 2012-04-01 2012-04-01 false Alumina (dried aluminum hydroxide). 73.1010... GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1010 Alumina (dried aluminum hydroxide). (a) Identity. (1) The color additive alumina (dried aluminum hydroxide) is a white,...

  13. 21 CFR 73.1010 - Alumina (dried aluminum hydroxide).

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Alumina (dried aluminum hydroxide). 73.1010... GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1010 Alumina (dried aluminum hydroxide). (a) Identity. (1) The color additive alumina (dried aluminum hydroxide) is a white,...

  14. 21 CFR 73.1010 - Alumina (dried aluminum hydroxide).

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 1 2011-04-01 2011-04-01 false Alumina (dried aluminum hydroxide). 73.1010... GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1010 Alumina (dried aluminum hydroxide). (a) Identity. (1) The color additive alumina (dried aluminum hydroxide) is a white,...

  15. 21 CFR 73.1010 - Alumina (dried aluminum hydroxide).

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 1 2014-04-01 2014-04-01 false Alumina (dried aluminum hydroxide). 73.1010... GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1010 Alumina (dried aluminum hydroxide). (a) Identity. (1) The color additive alumina (dried aluminum hydroxide) is a white,...

  16. 40 CFR 721.10120 - Siloxane modified alumina nanoparticles (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Siloxane modified alumina... Specific Chemical Substances § 721.10120 Siloxane modified alumina nanoparticles (generic). (a) Chemical... as siloxane modified alumina nanoparticles (PMN P-05-687) is subject to reporting under this...

  17. 40 CFR 721.10120 - Siloxane modified alumina nanoparticles (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Siloxane modified alumina... Specific Chemical Substances § 721.10120 Siloxane modified alumina nanoparticles (generic). (a) Chemical... as siloxane modified alumina nanoparticles (PMN P-05-687) is subject to reporting under this...

  18. REMOVING RADIUM FROM WATER BY PLAIN AND TREATED ACTIVATED ALUMINA

    EPA Science Inventory

    The research determined the feasibility of using BaSO4-impregnated activated alumina and plain activated alumina for radium removal from groundwater by fixed-bed adsorption. The major factors influencing radium adsorption onto the two types of alumina were identified. The radium ...

  19. The ATLAS Data Acquisition and High Level Trigger system

    NASA Astrophysics Data System (ADS)

    The ATLAS TDAQ Collaboration

    2016-06-01

    This paper describes the data acquisition and high level trigger system of the ATLAS experiment at the Large Hadron Collider at CERN, as deployed during Run 1. Data flow as well as control, configuration and monitoring aspects are addressed. An overview of the functionality of the system and of its performance is presented and design choices are discussed.

  20. 40 CFR 227.30 - High-level radioactive waste.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false High-level radioactive waste. 227.30 Section 227.30 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE EVALUATION OF PERMIT APPLICATIONS FOR OCEAN DUMPING OF MATERIALS Definitions § 227.30...

  1. MIXING PROCESSES IN HIGH-LEVEL WASTE TANKS

    EPA Science Inventory

    Flammable gases can be generated in DOE high-level waste tanks, including radiolytic hydrogen, and during cesium precipitation from salt solutions, benzene. Under normal operating conditions the potential for deflagration or detonation from these gases is precluded by purging and...

  2. THE XAL INFRASTRUCTURE FOR HIGH LEVEL CONTROL ROOM APPLICATIONS

    SciTech Connect

    Shishlo, Andrei P; Allen, Christopher K; Chu, Paul; Galambos, John D; Pelaia II, Tom

    2009-01-01

    XAL is a Java programming framework for building high-level control applications related to accelerator physics. The structure, details of implementation, and interaction between components, auxiliary XAL packages, and the latest modifications are discussed. A general overview of XAL applications created for the SNS project is presented.

  3. High-Level waste process and product data annotated bibliography

    SciTech Connect

    Stegen, G.E.

    1996-02-13

    The objective of this document is to provide information on available issued documents that will assist interested parties in finding available data on high-level waste and transuranic waste feed compositions, properties, behavior in candidate processing operations, and behavior on candidate product glasses made from those wastes. This initial compilation is only a partial list of available references.

  4. Typewriter Modifications for Persons Who Are High-Level Quadriplegics.

    ERIC Educational Resources Information Center

    O'Reagan, James R.; And Others

    Standard, common electric typewriters are not completely suited to the needs of a high-level quadriplegic typing with a mouthstick. Experiences show that for complete control of a typewriter a mouthstick user needs the combined features of one-button correction, electric forward and reverse indexing, and easy character viewing. To modify a…

  5. The Politics of High-Level Manpower Supply in Tanzania

    ERIC Educational Resources Information Center

    Brooke-Smith, Robin

    1978-01-01

    In its policies related to high-level manpower, the Tanzanian Government attaches great importance to the university, viewing it as a key institution in its policies for national development. Describes the difficulties the administration of President Nyerere has had in using the university as a political tool and analyzes various instances of…

  6. Method of making nanocrystalline alpha alumina

    DOEpatents

    Siegel, Richard W.; Hahn, Horst; Eastman, Jeffrey A.

    1992-01-01

    Method of making selected phases of nanocrystalline ceramic materials. Various methods of controlling the production of nanocrystalline alpha alumina and titanium oxygen phases are described. Control of the gas atmosphere and use of particular oxidation treatments give rise to the ability to control the particular phases provided in the aluminum/oxygen and titanium/oxygen system.

  7. Thermal Conductivity of Alumina-Toughened Zirconia Composites

    NASA Technical Reports Server (NTRS)

    Bansal, Narottam P.; Zhu, Dong-Ming

    2003-01-01

    10-mol% yttria-stabilized zirconia (10YSZ)-alumina composites containing 0 to 30 mol% alumina were fabricated by hot pressing at 1500 C in vacuum. Thermal conductivity of the composites, determined at various temperatures using a steady-state laser heat flux technique, increased with increase in alumina content. Composites containing 0, 5, and 10-mol% alumina did not show any change in thermal conductivity with temperature. However, those containing 20 and 30-mol% alumina showed a decrease in thermal conductivity with increase in temperature. The measured values of thermal conductivity were in good agreement with those calculated from simple rule of mixtures.

  8. Pyrochemical treatment of Idaho Chemical Processing Plant high-level waste calcine

    SciTech Connect

    Todd, T.A.; DelDebbio, J.A.; Nelson, L.O.; Sharpsten, M.R.

    1993-06-01

    The Idaho Chemical Processing Plant (ICPP), located at the Idaho National Engineering Laboratory (INEL), has reprocessed irradiated nuclear fuels for the US Department of Energy (DOE) since 1951 to recover uranium, krypton-85, and isolated fission products for interim treatment and immobilization. The acidic radioactive high-level liquid waste (HLLW) is routinely stored in stainless steel tanks and then, since 1963, calcined to form a dry granular solid. The resulting high-level waste (HLW) calcine is stored in seismically hardened stainless steel bins that are housed in underground concrete vaults. A research and development program has been established to determine the feasibility of treating ICPP HLW calcine using pyrochemical technology.This technology is described.

  9. Progress of the High Level Waste Program at the Defense Waste Processing Facility - 13178

    SciTech Connect

    Bricker, Jonathan M.; Fellinger, Terri L.; Staub, Aaron V.; Ray, Jeff W.; Iaukea, John F.

    2013-07-01

    The Defense Waste Processing Facility at the Savannah River Site treats and immobilizes High Level Waste into a durable borosilicate glass for safe, permanent storage. The High Level Waste program significantly reduces environmental risks associated with the storage of radioactive waste from legacy efforts to separate fissionable nuclear material from irradiated targets and fuels. In an effort to support the disposition of radioactive waste and accelerate tank closure at the Savannah River Site, the Defense Waste Processing Facility recently implemented facility and flowsheet modifications to improve production by 25%. These improvements, while low in cost, translated to record facility production in fiscal years 2011 and 2012. In addition, significant progress has been accomplished on longer term projects aimed at simplifying and expanding the flexibility of the existing flowsheet in order to accommodate future processing needs and goals. (authors)

  10. Industrial recovery capability. Final report. [Claus alumina catalyst for sulfur production

    SciTech Connect

    Gregg, D.W.

    1984-12-01

    This report provides an evaluation of the vulnerability - to a nuclear strike, terrorist attack, or natural disaster - of our national capacity to produce chlorine, beryllium, and a particular specialty alumina catalyst required for the production of sulfur. All of these industries are of critical importance to the United States economy. Other industries that were examined and found not to be particularly vulnerable are medicinal drugs and silicon wafers for electronics. Thus, only the three more vulnerable industries are addressed in this report.

  11. Dielectric Performance of High Purity HTCC Alumina at High Temperatures - A Comparison Study with Other Polycrystalline Alumina

    NASA Technical Reports Server (NTRS)

    Chen, Liang-Yu

    2012-01-01

    A very high purity (99.99+) high temperature co-fired ceramic (HTCC) alumina has recently become commercially available. The raw material of this HTCC alumina is very different from conventional HTCC alumina, and more importantly there is no glass additive in this co-fired material. Previously, selected HTCC and LTCC (low temperature co-fired ceramic) alumina materials were evaluated at high temperatures as dielectric and compared to a regularly sintered 96 polycrystalline alumina (96 Al2O3), where 96 alumina was used as the benchmark. A prototype packaging system based on regular 96 alumina with Au thick-film metallization successfully facilitated long term testing of high temperature silicon carbide (SiC) electronic devices for over 10,000 hours at 500C. In order to evaluate this new HTCC alumina for possible high temperature packaging applications, the dielectric properties of this HTCC alumina substrate were measured and compared with those of 96 alumina and a LTCC alumina from room temperature to 550C at frequencies of 120 Hz, 1 KHz, 10 KHz, 100 KHz, and 1 MHz. A parallel-plate capacitive device with dielectric of the HTCC alumina and precious metal electrodes were used for measurements of the dielectric constant and dielectric loss of the co-fired alumina material in the temperature and frequency ranges. The capacitance and AC parallel conductance of the capacitive device were directly measured by an AC impedance meter, and the dielectric constant and parallel AC conductivity of the dielectric were calculated from the capacitance and conductance measurement results. The temperature and frequency dependent dielectric constant, AC conductivity, and dissipation factor of the HTCC alumina substrate are presented and compared to those of 96 alumina. Other technical advantages of this new co-fired material for possible high packaging applications are also discussed.

  12. Structural studies of silica- and alumina-pinned nanocrystalline SnO2

    NASA Astrophysics Data System (ADS)

    O'Dell, L. A.; Savin, S. L. P.; Chadwick, A. V.; Smith, M. E.

    2005-09-01

    Sol-gel-prepared nanocrystalline tin (IV) oxide has been characterized by magic angle spinning nuclear magnetic resonance (MAS NMR) in a pure form and also with silica and alumina pinning phases present. The 119Sn MAS NMR lineshape was observed to broaden as the SnO2 nanocrystal sizes decreased, a reflection of the increasingly important contribution of the more disordered surface region. A second local Sn environment other than the cassiterite phase was observed, probably an orthorhombic phase that has previously been observed in nanoparticles of SnO2. The silica and alumina pinning particles were characterized by 29Si and 27Al MAS NMR. The silica pinning particles retained a high degree of disorder over the range of annealing temperatures, whereas alumina crystallized at ~1000 °C. A possible explanation for this difference is that since the alumina pinning particles are less successful at restricting nanocrystal growth than the silica particles, they may aggregate together and combine, hence they are larger, less constrained particles.

  13. Visual high-level regions respond to high-level stimulus content in the absence of low-level confounds.

    PubMed

    Schindler, Andreas; Bartels, Andreas

    2016-05-15

    High-level regions of the ventral stream exhibit strong category selectivity to stimuli such as faces, houses, or objects. However, recent studies suggest that at least part of this selectivity stems from low-level differences inherent to images of the different categories. For example, visual outdoor and indoor scenes as well as houses differ in spatial frequency, rectilinearity and obliqueness when compared to face or object images. Correspondingly, scene responsive para-hippocampal place area (PPA) showed strong preference to low-level properties of visual scenes also in the absence of high-level scene content. This raises the question whether all high-level responses in PPA, the fusiform face area (FFA), or the object-responsive lateral occipital compex (LOC) may actually be explained by systematic differences in low-level features. In the present study we contrasted two classes of simple stimuli consisting of ten rectangles each. While both were matched in visual low-level features only one class of rectangle arrangements gave rise to a percept compatible with a high-level 3D layout such as a scene or an object. We found that areas PPA, transverse occipital sulcus (TOS, also referred to as occipital place area, OPA), as well as FFA and LOC showed robust responses to the visual scene class compared to the low-level matched control. Our results suggest that visual category responsive regions are not purely driven by low-level visual features but also by the high-level perceptual stimulus interpretation. PMID:26975552

  14. 10 CFR 72.128 - Criteria for spent fuel, high-level radioactive waste, reactor-related greater than Class C waste...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 2 2013-01-01 2013-01-01 false Criteria for spent fuel, high-level radioactive waste, reactor-related greater than Class C waste, and other radioactive waste storage and handling. 72.128... STORAGE OF SPENT NUCLEAR FUEL, HIGH-LEVEL RADIOACTIVE WASTE, AND REACTOR-RELATED GREATER THAN CLASS...

  15. 10 CFR 72.128 - Criteria for spent fuel, high-level radioactive waste, reactor-related greater than Class C waste...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 2 2012-01-01 2012-01-01 false Criteria for spent fuel, high-level radioactive waste, reactor-related greater than Class C waste, and other radioactive waste storage and handling. 72.128... STORAGE OF SPENT NUCLEAR FUEL, HIGH-LEVEL RADIOACTIVE WASTE, AND REACTOR-RELATED GREATER THAN CLASS...

  16. 10 CFR 72.128 - Criteria for spent fuel, high-level radioactive waste, reactor-related greater than Class C waste...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Criteria for spent fuel, high-level radioactive waste, reactor-related greater than Class C waste, and other radioactive waste storage and handling. 72.128... STORAGE OF SPENT NUCLEAR FUEL, HIGH-LEVEL RADIOACTIVE WASTE, AND REACTOR-RELATED GREATER THAN CLASS...

  17. 10 CFR 72.128 - Criteria for spent fuel, high-level radioactive waste, reactor-related greater than Class C waste...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 2 2014-01-01 2014-01-01 false Criteria for spent fuel, high-level radioactive waste, reactor-related greater than Class C waste, and other radioactive waste storage and handling. 72.128... STORAGE OF SPENT NUCLEAR FUEL, HIGH-LEVEL RADIOACTIVE WASTE, AND REACTOR-RELATED GREATER THAN CLASS...

  18. Multipurpose optimization models for high level waste vitrification

    SciTech Connect

    Hoza, M.

    1994-08-01

    Optimal Waste Loading (OWL) models have been developed as multipurpose tools for high-level waste studies for the Tank Waste Remediation Program at Hanford. Using nonlinear programming techniques, these models maximize the waste loading of the vitrified waste and optimize the glass formers composition such that the glass produced has the appropriate properties within the melter, and the resultant vitrified waste form meets the requirements for disposal. The OWL model can be used for a single waste stream or for blended streams. The models can determine optimal continuous blends or optimal discrete blends of a number of different wastes. The OWL models have been used to identify the most restrictive constraints, to evaluate prospective waste pretreatment methods, to formulate and evaluate blending strategies, and to determine the impacts of variability in the wastes. The OWL models will be used to aid in the design of frits and the maximize the waste in the glass for High-Level Waste (HLW) vitrification.

  19. Radioactive high level waste insight modelling for geological disposal facilities

    NASA Astrophysics Data System (ADS)

    Carter, Alexander; Kelly, Martin; Bailey, Lucy

    Within this paper we present a simplified analytical model to provide insight into the key performance measures of a generic disposal system for high level waste within a geological disposal facility. The model assumes a low solubility waste matrix within a corrosion resistant disposal container surrounded by a low permeability buffer. Radionuclides migrate from the disposal area through a porous geosphere to the biosphere and give a radiological dose to a receptor. The system of equations describing the migration is transformed into Laplace space and an approximation used to determine peak values for the radionuclide mass transfer rate entering the biosphere. Results from the model are compared with those from more detailed numerical models for key radionuclides in the UK high level waste inventory. Such an insight model can provide a valuable second line of argument to assist in confirming the results of more detailed models and build confidence in the safety case for a geological disposal facility.

  20. RETENTION OF SULFATE IN HIGH LEVEL RADIOACTIVE WASTE GLASS

    SciTech Connect

    Fox, K.

    2010-09-07

    High level radioactive wastes are being vitrified at the Savannah River Site for long term disposal. Many of the wastes contain sulfate at concentrations that can be difficult to retain in borosilicate glass. This study involves efforts to optimize the composition of a glass frit for combination with the waste to improve sulfate retention while meeting other process and product performance constraints. The fabrication and characterization of several series of simulated waste glasses are described. The experiments are detailed chronologically, to provide insight into part of the engineering studies used in developing frit compositions for an operating high level waste vitrification facility. The results lead to the recommendation of a specific frit composition and a concentration limit for sulfate in the glass for the next batch of sludge to be processed at Savannah River.

  1. The tracking of high level waste shipments-TRANSCOM system

    SciTech Connect

    Johnson, P.E.; Joy, D.S.; Pope, R.B.

    1995-12-31

    The TRANSCOM (transportation tracking and communication) system is the U.S. Department of Energy`s (DOE`s) real-time system for tracking shipments of spent fuel, high-level wastes, and other high-visibility shipments of radioactive material. The TRANSCOM system has been operational since 1988. The system was used during FY1993 to track almost 100 shipments within the US.DOE complex, and it is accessed weekly by 10 to 20 users.

  2. Automatic rule generation for high-level vision

    NASA Technical Reports Server (NTRS)

    Rhee, Frank Chung-Hoon; Krishnapuram, Raghu

    1992-01-01

    Many high-level vision systems use rule-based approaches to solving problems such as autonomous navigation and image understanding. The rules are usually elaborated by experts. However, this procedure may be rather tedious. In this paper, we propose a method to generate such rules automatically from training data. The proposed method is also capable of filtering out irrelevant features and criteria from the rules.

  3. Mixing Processes in High-Level Waste Tanks - Final Report

    SciTech Connect

    Peterson, P.F.

    1999-05-24

    The mixing processes in large, complex enclosures using one-dimensional differential equations, with transport in free and wall jets is modeled using standard integral techniques. With this goal in mind, we have constructed a simple, computationally efficient numerical tool, the Berkeley Mechanistic Mixing Model, which can be used to predict the transient evolution of fuel and oxygen concentrations in DOE high-level waste tanks following loss of ventilation, and validate the model against a series of experiments.

  4. Alumina-on-alumina total hip prostheses in patients 40 years of age or younger.

    PubMed

    Bizot, P; Banallec, L; Sedel, L; Nizard, R

    2000-10-01

    To avoid the consequences of polyethylene wear in a high-risk population, 128 alumina-on-alumina total hip arthroplasties have been done in 104 consecutive patients. The maximum age of patients was 40 years. The main preoperative diagnoses were osteonecrosis and sequellae of congenital hip dislocation (71% of the hips). The same titanium alloy cemented stem was implanted in all of the hips. Four types of alumina acetabular component fixations were used: a cemented plain alumina socket (41 hips), a screw-in ring with an alumina insert (22 hips), a press-fit plain alumina socket (32 hips), and a press-fit titanium metal back with an alumina insert (33 hips). Eight patients (11 hips) died during the followup period. Sixteen revisions have been documented, 12 for acetabular aseptic loosening, three for bipolar loosening (two of which were septic), and one for unexplained pain. Eighty-eight hips in 74 patients have been followed up radiologically for 2 to 22 years. Wear was unmeasurable. Four additional sockets showed definite migration. The respective survival rates after 7 years were 94.1% for the cemented cup, 88.8% for the screw-in ring, 95.1% for cementless press-fit plain alumina socket and 94.3% for the metal-back press-fit component. The 10-year survival rate was 90.4% for the cemented socket and 88.8% for the screw-in ring. The 15-year survival rate was 78.9% for the cemented socket. Grafting was the only prognostic factor, with a survival rate of 62.6% after 10 years for the hips with a bone graft and of 90.1% for hips without a graft. The alumina-on-alumina bearing surfaces seem to be a valuable alternative to the standard metal-on-polyethylene system for young patients. However, an improvement in socket fixation is required to lengthen the life span of the prosthesis to match the life expectancy of this demanding population. PMID:11039794

  5. High level cognitive information processing in neural networks

    NASA Technical Reports Server (NTRS)

    Barnden, John A.; Fields, Christopher A.

    1992-01-01

    Two related research efforts were addressed: (1) high-level connectionist cognitive modeling; and (2) local neural circuit modeling. The goals of the first effort were to develop connectionist models of high-level cognitive processes such as problem solving or natural language understanding, and to understand the computational requirements of such models. The goals of the second effort were to develop biologically-realistic model of local neural circuits, and to understand the computational behavior of such models. In keeping with the nature of NASA's Innovative Research Program, all the work conducted under the grant was highly innovative. For instance, the following ideas, all summarized, are contributions to the study of connectionist/neural networks: (1) the temporal-winner-take-all, relative-position encoding, and pattern-similarity association techniques; (2) the importation of logical combinators into connection; (3) the use of analogy-based reasoning as a bridge across the gap between the traditional symbolic paradigm and the connectionist paradigm; and (4) the application of connectionism to the domain of belief representation/reasoning. The work on local neural circuit modeling also departs significantly from the work of related researchers. In particular, its concentration on low-level neural phenomena that could support high-level cognitive processing is unusual within the area of biological local circuit modeling, and also serves to expand the horizons of the artificial neural net field.

  6. Rheological Properties of Aqueous Nanometric Alumina Suspensions

    SciTech Connect

    Chuanping Li

    2004-12-19

    Colloidal processing is an effective and reliable approach in the fabrication of the advanced ceramic products. Successful colloidal processing of fine ceramic powders requires accurate control of the rheological properties. The accurate control relies on the understanding the influences of various colloidal parameters on the rheological properties. Almost all research done on the rheology paid less attention to the interactions of particle and solvent. However, the interactions of the particles are usually built up through the media in which the particles are suspended. Therefore, interactions of the particle with the media, the adsorbed layers on the particle surface, and chemical and physical properties of media themselves must influence the rheology of the suspension, especially for the dense suspensions containing nanosized particles. Relatively little research work has been reported in this area. This thesis addresses the rheological properties of nanometric alumina aqueous suspensions, and paying more attention to the interactions between particle and solvent, which in turn influence the particle-particle interactions. Dense nanometric alumina aqueous suspensions with low viscosity were achieved by environmentally-benign fructose additives. The rheology of nanometric alumina aqueous suspensions and its variation with the particle volume fraction and concentration of fructose were explored by rheometry. The adsorptions of solute (fructose) and solvent (water) on the nanometric alumina particle surfaces were measured and analyzed by TG/DSC, TOC, and NMR techniques. The mobility of water molecules in the suspensions and its variation with particle volume fractions and fructose additive were determined by the {sup 17}O NMR relaxation method. The interactions between the nanometric alumina particles in water and fructose solutions were investigated by AFM. The results indicated that a large number of water layers were physically bound on the particles' surfaces

  7. High level waste storage tank farms/242-A evaporator Standards/Requirements Identification Document (S/RID), Volume 6

    SciTech Connect

    Not Available

    1994-04-01

    The High-Level Waste Storage Tank Farms/242-A Evaporator Standards/Requirements Identification Document (S/RID) is contained in multiple volumes. This document (Volume 6) outlines the standards and requirements for the sections on: Environmental Restoration and Waste Management, Research and Development and Experimental Activities, and Nuclear Safety.

  8. Design of Phosphonated Imidazolium-Based Ionic Liquids Grafted on γ-Alumina: Potential Model for Hybrid Membranes.

    PubMed

    Pizzoccaro, Marie-Alix; Drobek, Martin; Petit, Eddy; Guerrero, Gilles; Hesemann, Peter; Julbe, Anne

    2016-01-01

    Imidazolium bromide-based ionic liquids bearing phosphonyl groups on the cationic part were synthesized and grafted on γ-alumina (γ-Al₂O₃) powders. These powders were prepared as companion samples of conventional mesoporous γ-alumina membranes, in order to favor a possible transfer of the results to supported membrane materials, which could be used for CO₂ separation applications. Effective grafting was demonstrated using energy dispersive X-ray spectrometry (EDX), N₂ adsorption measurements, fourier transform infrared spectroscopy (FTIR), and special attention was paid to (31)P and (13)C solid state nuclear magnetic resonance spectroscopy (NMR). PMID:27472321

  9. Experimental Study on Shear Response of 92.93 WT% Alumina Under Combined Pressure-Shear Loading

    NASA Astrophysics Data System (ADS)

    Yao, G. W.; Liu, Z. F.

    2007-12-01

    Pressure-shear plate impact experiments and soft recovery experiments were performed for 92.93 wt% aluminas with 75-mm-diameter compressed-gas gun. The in-material longitudinal and transverse particle velocities were traced by the embedded electromagnetic velocity gauges. The decoupled transverse particle velocities show an attenuation of shear waves with decreasing of material shear rigidity. SEM analysis of the intact samples shows heterogeneous meso-structures, and that of recovered samples shows the transit of intergranular microcracks to transgranular microcracks with increasing shock loading. The transverse shear promotes the microcracks nuclearing and expanding, and these microcracks result in remarkable dilation of alumina samples after unloading.

  10. Design of Phosphonated Imidazolium-Based Ionic Liquids Grafted on γ-Alumina: Potential Model for Hybrid Membranes

    PubMed Central

    Pizzoccaro, Marie-Alix; Drobek, Martin; Petit, Eddy; Guerrero, Gilles; Hesemann, Peter; Julbe, Anne

    2016-01-01

    Imidazolium bromide-based ionic liquids bearing phosphonyl groups on the cationic part were synthesized and grafted on γ-alumina (γ-Al2O3) powders. These powders were prepared as companion samples of conventional mesoporous γ-alumina membranes, in order to favor a possible transfer of the results to supported membrane materials, which could be used for CO2 separation applications. Effective grafting was demonstrated using energy dispersive X-ray spectrometry (EDX), N2 adsorption measurements, fourier transform infrared spectroscopy (FTIR), and special attention was paid to 31P and 13C solid state nuclear magnetic resonance spectroscopy (NMR). PMID:27472321

  11. An analysis of the technical status of high level radioactive waste and spent fuel management systems

    NASA Technical Reports Server (NTRS)

    English, T.; Miller, C.; Bullard, E.; Campbell, R.; Chockie, A.; Divita, E.; Douthitt, C.; Edelson, E.; Lees, L.

    1977-01-01

    The technical status of the old U.S. mailine program for high level radioactive nuclear waste management, and the newly-developing program for disposal of unreprocessed spent fuel was assessed. The method of long term containment for both of these waste forms is considered to be deep geologic isolation in bedded salt. Each major component of both waste management systems is analyzed in terms of its scientific feasibility, technical achievability and engineering achievability. The resulting matrix leads to a systematic identification of major unresolved technical or scientific questions and/or gaps in these programs.

  12. Fracture toughness measurements on a glass bonded sodalite high-level waste form.

    SciTech Connect

    DiSanto, T.; Goff, K. M.; Johnson, S. G.; O'Holleran, T. P.

    1999-05-19

    The electrometallurgical treatment of metallic spent nuclear fuel produces two high-level waste streams; cladding hulls and chloride salt. Argonne National Laboratory is developing a glass bonded sodalite waste form to immobilize the salt waste stream. The waste form consists of 75 Vol.% crystalline sodalite (containing the salt) with 25 Vol.% of an ''intergranular'' glassy phase. Microindentation fracture toughness measurements were performed on representative samples of this material using a Vickers indenter. Palmqvist cracking was confirmed by post-indentation polishing of a test sample. Young's modulus was measured by an acoustic technique. Fracture toughness, microhardness, and Young's modulus values are reported, along with results from scanning electron microscopy studies.

  13. High-Level Functional and Operational Requirements for the Advanced Fuel Cycle Facilty

    SciTech Connect

    Charles Park

    2006-12-01

    High-Level Functional & Operational Requirements for the AFCF -This document describes the principal functional and operational requirements for the proposed Advanced Fuel Cycle Facility (AFCF). The AFCF is intended to be the world's foremost facility for nuclear fuel cycle research, technology development, and demonstration. The facility will also support the near-term mission to develop and demonstrate technology in support of fuel cycle needs identified by industry, and the long-term mission to retain and retain U.S. leadership in fuel cycle operations. The AFCF is essential to demonstrate a more proliferation-resistant fuel cycle and make long-term improvements in fuel cycle effectiveness, performance and economy.

  14. Cementless bulk alumina socket: preliminary results at 6 years.

    PubMed

    Hamadouche, M; Nizard, R S; Meunier, A; Bizot, P; Sedel, L

    1999-09-01

    To avoid polyethylene wear observed in total hip replacement, an alumina-alumina combination has been used since 1977. The aim of this study is to report the results of a hybrid alumina-alumina total hip arthroplasty with a cementless press-fit bulk alumina socket and a cemented titanium alloy stem in 55 patients (62 hips) operated on between 1982 and 1990. The bearing surfaces were a 32-mm alumina head articulating within the alumina socket. Four failures occurred: 3 aseptic loosenings of the socket and 1 femoral head fracture. Considering aseptic loosening as the endpoint, the survival rate was 93.2% after 6 years. At a mean of 72.1 months' follow-up, 92.4% of the surviving hips were graded as very good or good using the Merle d'Aubigné-Postel hip score. Radiolucent lines were observed on the acetabular side in 68.1 of the hips. The future of this interface, which is probably fibrous, remains questionable. With the exception of 1 femoral head fracture, all revisions were related to failure of the bony fixation of the socket, and no problem was encountered related to the alumina-alumina friction coupling. Alumina sockets with other types of cementless fixation have therefore been designed and are presently under clinical investigation. PMID:10512442

  15. Technology of high-level nuclear waste disposal. Advances in the science and engineering of the management of high-level nuclear wastes. Volume 1

    SciTech Connect

    Hofmann, P.L.; Breslin, J.J.

    1981-01-01

    The papers in this volume cover the following subjects: waste isolation and the natural geohydrologic system; repository perturbations of the natural system; radionuclide migration through the natural system; and repository design technology. Individual papers are abstracted.

  16. Technology of high-level nuclear waste disposal. Advances in the science and engineering of the management of high-level nuclear wastes. Volume 2

    SciTech Connect

    Hofmann, P.L.

    1982-01-01

    The twenty papers in this volume are divided into three parts: site exploration and characterization; repository development and design; and waste package development and design. These papers represent the status of technology that existed in 1981 and 1982. Individual papers were processed for inclusion in the Energy Data Base.

  17. Modeling of Boehmite Leaching from Actual Hanford High-Level Waste Samples

    SciTech Connect

    Peterson, Reid A.; Lumetta, Gregg J.; Rapko, Brian M.; Poloski, Adam P.

    2007-06-27

    The Department of Energy plans to vitrify approximately 60,000 metric tons of high level waste sludge from underground storage tanks at the Hanford Nuclear Reservation. To reduce the volume of high level waste requiring treatment, a goal has been set to remove about 90 percent of the aluminum, which comprises nearly 70 percent of the sludge. Aluminum in the form of gibbsite and sodium aluminate can be easily dissolved by washing the waste stream with caustic, but boehmite, which comprises nearly half of the total aluminum, is more resistant to caustic dissolution and requires higher treatment temperatures and hydroxide concentrations. In this work, the dissolution kinetics of aluminum species during caustic leaching of actual Hanford high level waste samples is examined. The experimental results are used to develop a shrinking core model that provides a basis for prediction of dissolution dynamics from known process temperature and hydroxide concentration. This model is further developed to include the effects of particle size polydispersity, which is found to strongly influence the rate of dissolution.

  18. Safety analysis report vitrified high level waste type B shipping cask

    SciTech Connect

    1995-03-01

    This Safety Analysis Report describes the design, analyses, and principle features of the Vitrified High Level Waste (VHLW) Cask. In preparing this report a detailed evaluation of the design has been performed to ensure that all safety, licensing, and operational goals for the cask and its associated Department of Energy program can be met. The functions of this report are: (1) to fully document that all functional and regulatory requirements of 10CFR71 can be met by the package; and (2) to document the design and analyses of the cask for review by the Nuclear Regulatory Commission. The VHLW Cask is the reusable shipping package designed by GNSI under Department of Energy contract DE-AC04-89AL53-689 for transportation of Vitrified High Level Waste, and to meet the requirements for certification under 10CFR71 for a Type B(U) package. The VHLW cask has been designed as packaging for transport of canisters of Vitrified High Level Waste solidified at Department of Energy facilities.

  19. Comparison of selected foreign plans and practices for spent fuel and high-level waste management

    SciTech Connect

    Schneider, K.J.; Mitchell, S.J.; Lakey, L.T.; Johnson, A.B. Jr.; Hazelton, R.F.; Bradley, D.J.

    1990-04-01

    This report describes the major parameters for management of spent nuclear fuel and high-level radioactive wastes in selected foreign countries as of December 1989 and compares them with those in the United States. The foreign countries included in this study are Belgium, Canada, France, the Federal Republic of Germany, Japan, Sweden, Switzerland, and the United Kingdom. All the countries are planning for disposal of spent fuel and/or high-level wastes in deep geologic repositories. Most countries (except Canada and Sweden) plan to reprocess their spent fuel and vitrify the resultant high-level liquid wastes; in comparison, the US plans direct disposal of spent fuel. The US is planning to use a container for spent fuel as the primary engineered barrier. The US has the most developed repository concept and has one of the earliest scheduled repository startup dates. The repository environment presently being considered in the US is unique, being located in tuff above the water table. The US also has the most prescriptive regulations and performance requirements for the repository system and its components. 135 refs., 8 tabs.

  20. High-level waste management technology program plan

    SciTech Connect

    Harmon, H.D.

    1995-01-01

    The purpose of this plan is to document the integrated technology program plan for the Savannah River Site (SRS) High-Level Waste (HLW) Management System. The mission of the SRS HLW System is to receive and store SRS high-level wastes in a see and environmentally sound, and to convert these wastes into forms suitable for final disposal. These final disposal forms are borosilicate glass to be sent to the Federal Repository, Saltstone grout to be disposed of on site, and treated waste water to be released to the environment via a permitted outfall. Thus, the technology development activities described herein are those activities required to enable successful accomplishment of this mission. The technology program is based on specific needs of the SRS HLW System and organized following the systems engineering level 3 functions. Technology needs for each level 3 function are listed as reference, enhancements, and alternatives. Finally, FY-95 funding, deliverables, and schedules are s in Chapter IV with details on the specific tasks that are funded in FY-95 provided in Appendix A. The information in this report represents the vision of activities as defined at the beginning of the fiscal year. Depending on emergent issues, funding changes, and other factors, programs and milestones may be adjusted during the fiscal year. The FY-95 SRS HLW technology program strongly emphasizes startup support for the Defense Waste Processing Facility and In-Tank Precipitation. Closure of technical issues associated with these operations has been given highest priority. Consequently, efforts on longer term enhancements and alternatives are receiving minimal funding. However, High-Level Waste Management is committed to participation in the national Radioactive Waste Tank Remediation Technology Focus Area. 4 refs., 5 figs., 9 tabs.

  1. Li + ion diffusion in nanoscale alumina coatings

    NASA Astrophysics Data System (ADS)

    Johannes, Michelle; Bernstein, Noam

    Nanoscale coatings of alumina are used to stabilize surfaces for a variety of technologies. Diffusion of ions through these coatings is of primary importance: in some cases, diffusion is unwanted (e.g. corrosion) and in others (e.g. electrode materials), it is necessary. In this work DFT and AIMD calculations are used to investigate Li+ ion diffusion through a nano-layer of alumina, examining the phase (alpha, gamma, and amorphous), ion concentration, and electron count dependence. We look at the role of the surface itself in promoting diffusion. One of our main findings is that as the number of ions or charge increases, the diffusivity rises. We show how our data can explain electrochemical data from coated LiCoO2 cathodes and may point toward better and more efficient coatings for stabilizing electrodes.

  2. Fracture toughness and strength of 96% alumina

    SciTech Connect

    Price, D.B.; Chinn, R.E.; McNerney, K.R.; Brog, T.K.; Kim, C.Y.; Krutyholowa, M.W.; Chen, N.W.; Haun, M.J.

    1997-05-01

    There exists a need to understand the controlling factors that simultaneously impact strength and toughness in 96% alumina. The enhancement of both strength and toughness enables designers to extend the use limits and reliability for structural ceramics. This article presents mechanical property results from a group study examining the use of different alkaline-earth aluminosilicate intergranular compositions containing magnesium, calcium and strontium oxides (RO) in 96% alumina. Principal results address trends in indentation strength toughness and modulus of rupture. Trends in the data are presented relative to existing theories of thermal expansion mismatch toughening, grain-bridging crack-wake effect and crack deflection mechanisms. Strength is addressed in terms of strength after indentation, crack growth of indentation flaws and Weibull characterization for the strength distribution.

  3. Impact of AD995 alumina rods

    SciTech Connect

    Chhabildas, L.C.; Furnish, M.D.; Reinhart, W.D.; Grady, D.E.

    1997-10-01

    Gas guns and velocity interferometric techniques have been used to determine the loading behavior of an AD995 alumina rod 19 mm in diameter by 75 mm and 150 mm long, respectively. Graded-density materials were used to impact both bare and sleeved alumina rods while the velocity interferometer was used to monitor the axial-velocity of the free end of the rods. Results of these experiments demonstrate that (1) a time-dependent stress pulse generated during impact allows an efficient transition from the initial uniaxial strain loading to a uniaxial stress state as the stress pulse propagates through the rod, and (2) the intermediate loading rates obtained in this configuration lie between split Hopkinson bar and shock-loading techniques.

  4. Health Risk Assessments for Alumina Refineries

    PubMed Central

    Coffey, Patrick S.

    2014-01-01

    Objective: To describe contemporary air dispersion modeling and health risk assessment methodologies applied to alumina refineries and to summarize recent results. Methods: Air dispersion models using emission source and meteorological data have been used to assess ground-level concentrations (GLCs) of refinery emissions. Short-term (1-hour and 24-hour average) GLCs and annual average GLCs have been used to assess acute health, chronic health, and incremental carcinogenic risks. Results: The acute hazard index can exceed 1 close to refineries, but it is typically less than 1 at neighboring residential locations. The chronic hazard index is typically substantially less than 1. The incremental carcinogenic risk is typically less than 10−6. Conclusions: The risks of acute health effects are adequately controlled, and the risks of chronic health effects and incremental carcinogenic risks are negligible around referenced alumina refineries. PMID:24806721

  5. Activation of consolidation processes of alumina ceramics

    NASA Astrophysics Data System (ADS)

    Matrenin, S. V.; Zenin, B. S.; Tayukin, R. V.

    2016-02-01

    The methods for activating sintering ceramics based on Al2O3 by mechanical activation in the planetary mill, by adding in the mixture of nanopowders (NP) Al, Al2O3, and submicron powder TiO2, and by applying the technology of spark plasma sintering (SPS) are developed. It has been shown that adding the nanopowder up to 20 wt. % Al2O3 in a coarse powder α-Al2O3 activates the sintering process resulting in increased density and hardness of the sintered alumina ceramics. Substantial effect of increasing density of alumina ceramics due to adding the submicron powder TiO2 in the compound of initial powder mixtures has been established.

  6. Corrosion and failure processes in high-level waste tanks

    SciTech Connect

    Mahidhara, R.K.; Elleman, T.S.; Murty, K.L.

    1992-11-01

    A large amount of radioactive waste has been stored safely at the Savannah River and Hanford sites over the past 46 years. The aim of this report is to review the experimental corrosion studies at Savannah River and Hanford with the intention of identifying the types and rates of corrosion encountered and indicate how these data contribute to tank failure predictions. The compositions of the High-Level Wastes, mild steels used in the construction of the waste tanks and degradation-modes particularly stress corrosion cracking and pitting are discussed. Current concerns at the Hanford Site are highlighted.

  7. CLASSIFICATION OF THE MGR DEFENSE HIGH LEVEL WASTE DISPOSAL CONTIANER

    SciTech Connect

    J.A. Ziegler

    1999-08-31

    The purpose of this analysis is to document the Quality Assurance (QA) classification of the Monitored Geologic Repository (MGR) defense high-level waste disposal container system structures, systems and components (SSCs) performed by the MGR Safety Assurance Department. This analysis also provides the basis for revision of YMP/90-55Q, Q-List (YMP 1998). The Q-List identifies those MGR SSCs subject to the requirements of DOE/RW-0333PY ''Quality Assurance Requirements and Description'' (QARD) (DOE 1998).

  8. Ionization chamber for measurements of high-level tritium gas

    SciTech Connect

    Carstens, D.H.W.; David, W.R.

    1980-01-01

    The construction and calibration of a simple ionization-chamber apparatus for measurement of high level tritium gas is described. The apparatus uses an easily constructed but rugged chamber containing the unknown gas and an inexpensive digital multimeter for measuring the ion current. The equipment after calibration is suitable for measuring 0.01 to 100% tritium gas in hydrogen-helium mixes with an accuracy of a few percent. At both the high and low limits of measurements deviations from the predicted theoretical current are observed. These are briefly discussed.

  9. Solidification of Savannah River Plant high-level waste

    SciTech Connect

    Maher, R; Shafranek, L F; Stevens, III, W R

    1983-01-01

    The Department of Energy, in accord with recommendations from the Du Pont Company, has started construction of a Defense Waste Processing Facility (DWPF) at the Savannah River Plant. The facility should be completed by the end of 1988, and full-scale operation should begin in 1990. This facility will immobilize in borosilicate glass the large quantity of high-level radioactive waste now stored at the plant plus the waste to be generated from continued chemical reprocessing operations. The existing wastes at the Savannah River Plant will be completely converted by about 2010. 21 figures.

  10. High-level neutron coincidence counter maintenance manual

    SciTech Connect

    Swansen, J.; Collinsworth, P.

    1983-05-01

    High-level neutron coincidence counter operational (field) calibration and usage is well known. This manual makes explicit basic (shop) check-out, calibration, and testing of new units and is a guide for repair of failed in-service units. Operational criteria for the major electronic functions are detailed, as are adjustments and calibration procedures, and recurrent mechanical/electromechanical problems are addressed. Some system tests are included for quality assurance. Data on nonstandard large-scale integrated (circuit) components and a schematic set are also included.

  11. Market Designs for High Levels of Variable Generation: Preprint

    SciTech Connect

    Milligan, M.; Holttinen, H.; Kiviluoma, J.; Orths, A.; Lynch, M.; Soder, L.

    2014-10-01

    Variable renewable generation is increasing in penetration in modern power systems, leading to higher variability in the supply and price of electricity as well as lower average spot prices. This raises new challenges, particularly in ensuring sufficient capacity and flexibility from conventional technologies. Because the fixed costs and lifetimes of electricity generation investments are significant, designing markets and regulations that ensure the efficient integration of renewable generation is a significant challenge. This papers reviews the state of play of market designs for high levels of variable generation in the United States and Europe and considers new developments in both regions.

  12. Fast Glazing of Alumina/Silica Tiles

    NASA Technical Reports Server (NTRS)

    Creedon, J. F.; Gzowski, E. R.; Wheeler, W. H.

    1986-01-01

    Technique for applying ceramic coating to fibrous silica/alumina insulation tiles prevents cracks and substantially reduces firing time. To reduce thermal stresses in tile being coated, high-temperature, shorttime firing schedule implemented. Such schedule allows coating to mature while substrate remains at relatively low temperature, reducing stress differential between coating and substrate. Technique used to repair tiles with damaged coatings and possibly used in heat-treating objects made of materials having different thermal-expansion coefficients.

  13. High contrast laser marking of alumina

    NASA Astrophysics Data System (ADS)

    Penide, J.; Quintero, F.; Riveiro, A.; Fernández, A.; del Val, J.; Comesaña, R.; Lusquiños, F.; Pou, J.

    2015-05-01

    Alumina serves as raw material for a broad range of advanced ceramic products. These elements should usually be identified by some characters or symbols printed directly on them. In this sense, laser marking is an efficient, reliable and widely implemented process in industry. However, laser marking of alumina still leads to poor results since the process is not able to produce a dark mark, yielding bad contrast. In this paper, we present an experimental study on the process of marking alumina by three different lasers working in two wavelengths: 1064 nm (Near-infrared) and 532 nm (visible, green radiation). A colorimetric analysis has been carried out in order to compare the resulting marks and its contrast. The most suitable laser operating conditions were also defined and are reported here. Moreover, the physical process of marking by NIR lasers is discussed in detail. Field Emission Scanning Electron Microscopy, High Resolution Transmission Electron Microscopy and X-ray Photoelectron Spectroscopy were also employed to analyze the results. Finally, we propose an explanation for the differences of the coloration induced under different atmospheres and laser parameters. We concluded that the atmosphere is the key parameter, being the inert one the best choice to produce the darkest marks.

  14. Compression Testing of Alumina Fiber Insulation

    NASA Technical Reports Server (NTRS)

    Vaughn, Wallace L.

    2006-01-01

    A series of tests were conducted to measure the response of alumina fiber insulation to compression loading. The alumina fiber insulation is a candidate gasket material for the Space Shuttle Government Furnished Equipment (GFE) Tile Overlay Repair. Tests were conducted at room temperature and 2300 F. The alumina fiber insulation is a fibrous insulation blanket which was supplied to Langley in two forms, a nominal 3 lb/ft3 version and a nominal 9 lb/ft3 version. The 3 lb/ft3 material was tested as sheets 0.15 and 0.25 inches thick and the 9 lb/ft3 material in sheets 1 inch thick. The material showed very non-linear compression behavior with the compressive resistance of the material increasing as the material was compressed. The 3 lb/ft3 0.15-inch thick material required 4.1 psi to reach the nominal installation thickness of 0.045 inches and retain a load of 2.1 lbs during unloading. Testing at 2300 F resulted in a stiffer more board-like material. The 3 lb/ft3 0.15-inch thick material retained 1 psi of compressive resistance after a 10 minute hold at 2300 F and 0.045 inches thickness.

  15. High level radioactive waste glass production and product description

    SciTech Connect

    Sproull, J.F.; Marra, S.L.; Jantzen, C.M.

    1993-12-01

    This report examines borosilicate glass as a means of immobilizing high-level radioactive wastes. Borosilicate glass will encapsulate most of the defense and some of the commercial HLW in the US. The resulting waste forms must meet the requirements of the WA-SRD and the WAPS, which include a short term PCT durability test. The waste form producer must report the composition(s) of the borosilicate waste glass(es) produced but can choose the composition(s) to meet site-specific requirements. Although the waste form composition is the primary determinant of durability, the redox state of the glass; the existence, content, and composition of crystals; and the presence of glass-in-glass phase separation can affect durability. The waste glass should be formulated to avoid phase separation regions. The ultimate result of this effort will be a waste form which is much more stable and potentially less mobile than the liquid high level radioactive waste is currently.

  16. Executive functions in kindergarteners with high levels of disruptive behaviours.

    PubMed

    Monette, Sébastien; Bigras, Marc; Guay, Marie-Claude

    2015-11-01

    Executive function (EF) deficits have yet to be demonstrated convincingly in children with disruptive behaviour disorders (DBD), as only a few studies have reported these. The presence of EF weaknesses in children with DBD has often been contested on account of the high comorbidity between DBD and attention-deficit/hyperactivity disorder (ADHD) and of methodological shortcomings regarding EF measures. Against this background, the link between EF and disruptive behaviours in kindergarteners was investigated using a carefully selected battery of EF measures. Three groups of kindergarteners were compared: (1) a group combining high levels of disruptive behaviours and ADHD symptoms (COMB); (2) a group presenting high levels of disruptive/aggressive behaviours and low levels of ADHD symptoms (AGG); and (3) a normative group (NOR). Children in the COMB and AGG groups presented weaker inhibition capacities compared with normative peers. Also, only the COMB group showed weaker working memory capacities compared with the NOR group. Results support the idea that preschool children with DBD have weaker inhibition capacities and that this weakness could be common to both ADHD and DBD. PMID:26198079

  17. How to achieve high-level expression of microbial enzymes

    PubMed Central

    Liu, Long; Yang, Haiquan; Shin, Hyun-dong; Chen, Rachel R.; Li, Jianghua; Du, Guocheng; Chen, Jian

    2013-01-01

    Microbial enzymes have been used in a large number of fields, such as chemical, agricultural and biopharmaceutical industries. The enzyme production rate and yield are the main factors to consider when choosing the appropriate expression system for the production of recombinant proteins. Recombinant enzymes have been expressed in bacteria (e.g., Escherichia coli, Bacillus and lactic acid bacteria), filamentous fungi (e.g., Aspergillus) and yeasts (e.g., Pichia pastoris). The favorable and very advantageous characteristics of these species have resulted in an increasing number of biotechnological applications. Bacterial hosts (e.g., E. coli) can be used to quickly and easily overexpress recombinant enzymes; however, bacterial systems cannot express very large proteins and proteins that require post-translational modifications. The main bacterial expression hosts, with the exception of lactic acid bacteria and filamentous fungi, can produce several toxins which are not compatible with the expression of recombinant enzymes in food and drugs. However, due to the multiplicity of the physiological impacts arising from high-level expression of genes encoding the enzymes and expression hosts, the goal of overproduction can hardly be achieved, and therefore, the yield of recombinant enzymes is limited. In this review, the recent strategies used for the high-level expression of microbial enzymes in the hosts mentioned above are summarized and the prospects are also discussed. We hope this review will contribute to the development of the enzyme-related research field. PMID:23686280

  18. High level language-based robotic control system

    NASA Technical Reports Server (NTRS)

    Rodriguez, Guillermo (Inventor); Kruetz, Kenneth K. (Inventor); Jain, Abhinandan (Inventor)

    1994-01-01

    This invention is a robot control system based on a high level language implementing a spatial operator algebra. There are two high level languages included within the system. At the highest level, applications programs can be written in a robot-oriented applications language including broad operators such as MOVE and GRASP. The robot-oriented applications language statements are translated into statements in the spatial operator algebra language. Programming can also take place using the spatial operator algebra language. The statements in the spatial operator algebra language from either source are then translated into machine language statements for execution by a digital control computer. The system also includes the capability of executing the control code sequences in a simulation mode before actual execution to assure proper action at execution time. The robot's environment is checked as part of the process and dynamic reconfiguration is also possible. The languages and system allow the programming and control of multiple arms and the use of inward/outward spatial recursions in which every computational step can be related to a transformation from one point in the mechanical robot to another point to name two major advantages.

  19. High level language-based robotic control system

    NASA Technical Reports Server (NTRS)

    Rodriguez, Guillermo (Inventor); Kreutz, Kenneth K. (Inventor); Jain, Abhinandan (Inventor)

    1996-01-01

    This invention is a robot control system based on a high level language implementing a spatial operator algebra. There are two high level languages included within the system. At the highest level, applications programs can be written in a robot-oriented applications language including broad operators such as MOVE and GRASP. The robot-oriented applications language statements are translated into statements in the spatial operator algebra language. Programming can also take place using the spatial operator algebra language. The statements in the spatial operator algebra language from either source are then translated into machine language statements for execution by a digital control computer. The system also includes the capability of executing the control code sequences in a simulation mode before actual execution to assure proper action at execution time. The robot's environment is checked as part of the process and dynamic reconfiguration is also possible. The languages and system allow the programming and control of multiple arms and the use of inward/outward spatial recursions in which every computational step can be related to a transformation from one point in the mechanical robot to another point to name two major advantages.

  20. VITRIFICATION OF HIGH LEVEL WASTE AT THE SAVANNAH RIVER SITE

    SciTech Connect

    Fox, K.; Peeler, D.

    2009-06-17

    The objective of this study was to experimentally measure the properties and performance of a series of glasses with compositions that could represent high level waste Sludge Batch 5 (SB5) as vitrified at the Savannah River Site Defense Waste Processing Facility. These data were used to guide frit optimization efforts as the SB5 composition was finalized. Glass compositions for this study were developed by combining a series of SB5 composition projections with a group of candidate frits. The study glasses were fabricated using depleted uranium and their chemical compositions, crystalline contents and chemical durabilities were characterized. Trevorite was the only crystalline phase that was identified in a few of the study glasses after slow cooling, and is not of concern as spinels have been shown to have little impact on the durability of high level waste glasses. Chemical durability was quantified using the Product Consistency Test (PCT). All of the glasses had very acceptable durability performance. The results of this study indicate that a frit composition can be identified that will provide a processable and durable glass when combined with SB5.

  1. Permitting plan for the high-level waste interim storage

    SciTech Connect

    Deffenbaugh, M.L.

    1997-04-23

    This document addresses the environmental permitting requirements for the transportation and interim storage of solidified high-level waste (HLW) produced during Phase 1 of the Hanford Site privatization effort. Solidified HLW consists of canisters containing vitrified HLW (glass) and containers that hold cesium separated during low-level waste pretreatment. The glass canisters and cesium containers will be transported to the Canister Storage Building (CSB) in a U.S. Department of Energy (DOE)-provided transportation cask via diesel-powered tractor trailer. Tri-Party Agreement (TPA) Milestone M-90 establishes a new major milestone, and associated interim milestones and target dates, governing acquisition and/or modification of facilities necessary for: (1) interim storage of Tank Waste Remediation Systems (TWRS) immobilized HLW (IHLW) and other canistered high-level waste forms; and (2) interim storage and disposal of TWRS immobilized low-activity tank waste (ILAW). An environmental requirements checklist and narrative was developed to identify the permitting path forward for the HLW interim storage (HLWIS) project (See Appendix B). This permitting plan will follow the permitting logic developed in that checklist.

  2. Synthesis and properties of high-purity alumina

    SciTech Connect

    Martin, E.S.; Weaver, M.L. . Chemical Systems Div.)

    1993-07-01

    High-purity alumina is intended primarily for the high-pressure sodium-vapor lamp envelope market and other specialty alumina applications such as abrasives, catalysts, and structural ceramics. High-purity alumina must calcine to Al[sub 2]O[sub 3] with minimal metal impurities ([>=]99.99% Al[sub 2]O[sub 3]). Sulfate and chloride impurities are also undesirable. High-purity alumina should have less than 20ppm alkali and alkaline-earth metals, and less than 10 ppm each in transition-metal impurities. A process for synthesizing alumina by converting pure aluminum metal to aluminum hydroxide and the resultant alumina properties are described.

  3. A simple procedure to prepare spherical {alpha}-alumina powders

    SciTech Connect

    Liu Hongyu; Ning Guiling Gan Zhihong; Lin Yuan

    2009-04-02

    Spherical {alpha}-alumina powders were prepared by the controlled hydrolysis of aluminum isopropoxide in a hydrolysis system consisting of octanol and acetonitrile. Diverse solvents to dissolve reactant formed diverse hydrolysis systems and affected particle shape of {alpha}-alumina powders. The precursors crystallized to {gamma}-alumina at 1000 deg. C and converted to {alpha}-alumina at 1150 deg. C without intermediate phases. The particle morphology of precursor was retained after it crystallized to {alpha}-alumina. The heating rate influenced the particle shape and the state of agglomeration during calcination process. The thermal properties of the precursors were characterized by thermal gravimetric and differential thermal analysis. X-ray diffraction technique was used to confirm the conversion of crystalline phase of alumina powders from amorphous to {alpha}-phase. Transmission electron microscopy was used to investigate the morphologies and size of the precursors and products.

  4. High-level power analysis and optimization techniques

    NASA Astrophysics Data System (ADS)

    Raghunathan, Anand

    1997-12-01

    This thesis combines two ubiquitous trends in the VLSI design world--the move towards designing at higher levels of design abstraction, and the increasing importance of power consumption as a design metric. Power estimation and optimization tools are becoming an increasingly important part of design flows, driven by a variety of requirements such as prolonging battery life in portable computing and communication devices, thermal considerations and system cooling and packaging costs, reliability issues (e.g. electromigration, ground bounce, and I-R drops in the power network), and environmental concerns. This thesis presents a suite of techniques to automatically perform power analysis and optimization for designs at the architecture or register-transfer, and behavior or algorithm levels of the design hierarchy. High-level synthesis refers to the process of synthesizing, from an abstract behavioral description, a register-transfer implementation that satisfies the desired constraints. High-level synthesis tools typically perform one or more of the following tasks: transformations, module selection, clock selection, scheduling, and resource allocation and assignment (also called resource sharing or hardware sharing). High-level synthesis techniques for minimizing the area, maximizing the performance, and enhancing the testability of the synthesized designs have been investigated. This thesis presents high-level synthesis techniques that minimize power consumption in the synthesized data paths. This thesis investigates the effects of resource sharing on the power consumption in the data path, provides techniques to efficiently estimate power consumption during resource sharing, and resource sharing algorithms to minimize power consumption. The RTL circuit that is obtained from the high-level synthesis process can be further optimized for power by applying power-reducing RTL transformations. This thesis presents macro-modeling and estimation techniques for switching

  5. Development of silver impregnated alumina for iodine separation from off-gas streams

    SciTech Connect

    Funabashi, Kiyomi; Fukasawa, Tetsuo; Kikuchi, Makoto

    1995-02-01

    An inorganic iodine adsorbent, silver impregnated alumina (AgA), has been developed to separate iodine effectively from off-gas streams of nuclear facilities and to decrease the volume of waste (spent adsorbent). Iodine removal efficiency was improved at relatively high humidity by using alumina carrier with two different pore diameters. Waste volume reduction was achieved by impregnating relatively large amounts of silver into the alumina pores. The developed adsorbent was tested first with simulated off-gas streams under various experimental conditions and finally with actual off-gas streams of the Karlsruhe reprocessing plant. The decontamination factor (DF) was about 100 with the AgA bed depth of 2cm at 70% relative humidity, which was a DF one order higher than that when AgA with one pore size was used. Iodine adsorption capacity was checked by passing excess iodine into the AgA bed. Values were about 0.12 and 0.35 g-I/cm`-AgA bed for 10 and 24wt% silver impregnated AgA, respectively. The results obtained in this study demonstrated the applicability of the developed AgA to the off-gas treatment system of nuclear facilities.

  6. New experience with alumina-on-alumina ceramic bearings for total hip arthroplasty.

    PubMed

    D'Antonio, James; Capello, William; Manley, Michael; Bierbaum, Benjamin

    2002-06-01

    A major challenge for total hip arthroplasty is to minimize wear and osteolysis in young, active patients. Alumina ceramic bearings have shown superior wear resistance and lubrication and do not carry the risk of ion release. In a prospective randomized study, 514 hips were implanted. All patients (average age, 53 years) received the same press-fit hydroxyapatite coated femoral stem; two thirds (345 hips) received alumina ceramic bearings, and one third (169 hips) received a cobalt-chrome-on-polyethylene bearing. At a mean follow-up of 35.2 months (range, 24-48 months), there was no significant difference in clinical performance between the patient cohorts. No ceramic fracture or alumina ceramic bearing failure occurred. This new experience involves the use of improved ceramic materials and new design considerations that eliminate the risks and complications of past experiences with ceramic implants and provides a safe bearing option for young patients. PMID:12066265

  7. Free-standing alumina nanobottles and nanotubes pre-integrated into nanoporous alumina membranes

    NASA Astrophysics Data System (ADS)

    Fang, Jinghua; Levchenko, Igor; (Ken Ostrikov, Kostya

    2014-08-01

    A novel interfacial structure consisting of long (up to 5 μm), thin (about 300 nm), highly-ordered, free-standing, highly-reproducible aluminum oxide nanobottles and long tubular nanocapsules attached to a rigid, thin (less than 1 μm) nanoporous anodic alumina membrane is fabricated by simple, fast, catalyst-free, environmentally friendly voltage-pulse anodization. A growth mechanism is proposed based on the formation of straight channels in alumina membrane by anodization, followed by neck formation due to a sophisticated voltage control during the process. This process can be used for the fabrication of alumina nanocontainers with highly controllable geometrical size and volume, vitally important for various applications such as material and energy storage, targeted drug and diagnostic agent delivery, controlled drug and active agent release, gene and biomolecule reservoirs, micro-biologically protected platforms, nano-bioreactors, tissue engineering and hydrogen storage.

  8. A proposed classification system for high-level and other radioactive wastes

    SciTech Connect

    Kocher, D. C.; Croff, A. G.

    1987-06-01

    This report presents a proposal for quantitative and generally applicable risk-based definitions of high-level and other radioactive wastes. On the basis of historical descriptions and definitions of high-level waste (HLW), in which HLW has been defined in terms of its source as waste from reprocessing of spent nuclear fuel, we propose a more general definition based on the concept that HLW has two distinct attributes: HLW is (1) highly radioactive and (2) requires permanent isolation. This concept leads to a two-dimensional waste classification system in which one axis, related to ''requires permanent isolation,'' is associated with long-term risks from waste disposal and the other axis, related to ''highly radioactive,'' is associated with shorter-term risks due to high levels of decay heat and external radiation. We define wastes that require permanent isolation as wastes with concentrations of radionuclides exceeding the Class-C limits that are generally acceptable for near-surface land disposal, as specified in the US Nuclear Regulatory Commission's rulemaking 10 CFR Part 61 and its supporting documentation. HLW then is waste requiring permanent isolation that also is highly radioactive, and we define ''highly radioactive'' as a decay heat (power density) in the waste greater than 50 W/m/sup 3/ or an external radiation dose rate at a distance of 1 m from the waste greater than 100 rem/h (1 Sv/h), whichever is the more restrictive. This proposal also results in a definition of Transuranic (TRU) Waste and Equivalent as waste that requires permanent isolation but is not highly radioactive and a definition of low-level waste (LLW) as waste that does not require permanent isolation without regard to whether or not it is highly radioactive.

  9. Alumina Solubility and Diffusion Coefficient of the Dissolved Alumina Species in Low-Temperature Fluoride Electrolytes

    NASA Astrophysics Data System (ADS)

    Frazer, E. J.; Thonstad, J.

    2010-06-01

    The solubility of alumina was measured by rotating an alumina cylinder (~500 rpm) in a high-purity melt for ~3 to 6 hours, crushing and sampling the frozen melt, and determining the oxygen content in a Leco analyzer. The alumina solubilities determined were as follows: (1) 3.2 ± 0.3 wt pct in NaF-AlF3 eutectic at 1023 K (750 °C); (2) 3.0 ± 0.3 wt pct in NaF-AlF3-CaF2 (5 wt pct) at 1023 K (750 °C); and (3) 5.2 ± 0.5 wt pct in a KF-AlF3 eutectic at 1003 K (730 °C). The alumina solubility in the KF-AlF3 eutectic was 2 wt pct more than in the sodium analogue, offering the possibility of operating a low-temperature aluminum smelting cell without the need for an alumina slurry. The diffusion coefficient of the dissolved alumina species was determined in the NaF-AlF3 eutectic at 1023 K (750 °C) using the rotating disc method and applying the Levich equation. Through a limited range of rotation rates, the system seemed to be mass-transfer controlled, and the diffusion coefficient was estimated to be in the range 1.8 to 2.2 × 10-6 cm2 s-1. This value is about five times lower than the values encountered at traditional aluminum smelting temperatures (~1233 K (960 °C)) and would result in relatively low mass transfer coefficients.

  10. Amorphous alumina oxidation protective coatings for Zircaloy based on a compositional gradient layer system

    NASA Astrophysics Data System (ADS)

    Park, Sang Tae

    Waterside corrosion of the Zircaloy cladding encasing the uranium oxide pellets is one of the primary factors limiting high "burn up" of nuclear fuel in pressurized water reactors (PWRs). High "burn up" can significantly impact plant safety and economics. Amorphous aluminum oxide coatings with aluminum-based compositional gradient layers (CGLs) were fabricated to develop ceramic coating corrosion protection systems for Zircaloy. Aluminum films were deposited on Zircaloy substrates by electron-beam evaporation, and two-step heat treatments were performed at near the melting temperature of aluminum. Amorphous alumina coatings by rf magnetron sputtering were overcoated on the CGL structures. Morphological and compositional studies were completed using field emission scanning electron microscopy (FE SEM), energy dispersive x-ray analysis (EDX), and auger electron spectroscopy (AES). The AES depth profiles of the annealed coatings showed that gradient compositions of Al, Zr, and O were obtained. Glancing angle x-ray diffraction (GAXRD) analysis showed that a variety of intermetallic and oxide phases (such as Al3Zr, Al2Zr3, Al2O3, ZrO2 and Zr3O) were formed in the coatings during processing. The intermetallic layers improved the adhesion property of the alumina overcoating to Zircaloy substrate, and functioned as oxidation resistant layers. In spite of the successful construction of the compositional gradient layer system with a good adhesion and thermal stability, and the report about the stability of pure alumina and amorphous ceramics in hydrothermal conditions, the amorphous alumina coatings in our study were not stable under nuclear reactor conditions of subcritical water at 350°C and 20.1 MPa (3000 psi). We investigated the behavior of amorphous alumina thin films deposited on Zircaloy substrates in the near-supercritical water. When the coatings were exposed to the subcritical conditions, hydrothermally grown well-faceted crystallite formation was observed

  11. Method for preparing Pb-.beta."-alumina ceramic

    DOEpatents

    Hellstrom, Eric E.

    1986-01-01

    A process is disclosed for preparing impermeable, polycrystalline samples of Pb-.beta."-alumina ceramic from Na-.beta."-alumina ceramic by ion exchange. The process comprises two steps. The first step is a high-temperature vapor phase exchange of Na by K, followed by substitution of Pb for K by immersing the sample in a molten Pb salt bath. The result is a polycrystalline Pb-.beta."-alumina ceramic that is substantially crack-free.

  12. Sintering of beta-type alumina bodies using alpha-alumina encapsulation

    DOEpatents

    McEntire, Bryan J.; Virkar, Anil V.

    1981-01-01

    A method of sintering a shaped green, beta-type alumina body comprising: (A) inserting said body into an open chamber prepared by exposing the interior surface of a container consisting essentially of at least about 50 weight percent of alpha-alumina and a remainder of other refractory material to a sodium oxide or sodium oxide producing environment; (B) sealing the chamber; and heating the chamber with the shaped body encapsulated therein to a temperature and for a time necessary to sinter said body to the desired density. The encapsulation chamber prepared as described above is also claimed.

  13. Modeling and optimization of defense high level waste removal sequencing

    NASA Astrophysics Data System (ADS)

    Paul, Pran Krishna

    A novel methodology has been developed which makes possible a very fast running computational tool, capable of performing 30 to 50 years of simulation of the entire Savannah River Site (SRS) high level waste complex in less than 2 minutes on a work station. The methodology has been implemented in the Production Planning Model (ProdMod) simulation code which uses Aspen Technology's dynamic simulation software development package SPEEDUP. ProdMod is a pseudo-dynamic simulation code solely based on algebraic equations, using no differential equations. The dynamic nature of the plant process is captured using linear constructs in which the time dependence is implicit. Another innovative approach implemented in ProdMod development is the mapping of event-space on to time-space and vice versa, which accelerates the computation without sacrificing the necessary details in the event-space. ProdMod uses this approach in coupling the time-space continuous simulation with the event-space batch simulation, avoiding the discontinuities inherent in dynamic simulation batch processing. In addition, a general purpose optimization scheme has been devised based on the pseudo-dynamic constructs and the event- and time-space algorithms of ProdMod. The optimization scheme couples a FORTRAN based stand-alone optimization driver with the SPEEDUP based ProdMod simulator to perform dynamic optimization. The scheme is capable of generating single or multiple optimal input conditions for different types of objective functions over single or multiple years of operations depending on the nature of the objective function and operating constraints. The resultant optimal inputs are then interfaced with ProdMod to simulate the dynamic behavior of the waste processing operations. At the conclusion on an optimized advancement step, the simulation parameters are then passed to the optimization driver to generate the next set of optimized parameters. An optimization algorithm using linear programming

  14. Porous Alumina Prepared from Diethylaluminum Amide, Acetone, and Water

    SciTech Connect

    Wilcox, Lize; Burnside, Gaylen G.; Kiranga, Beatrice; Shekhawat, Ritu; Mazumder, Malay K.; Hawk, Roger M.; Lindquist, David A.; Burton, Sarah D.)

    2003-01-14

    Mesoporous aluminas are valued catalysts because they exhibit a combination of properties that allow both long life and activity. The surface area, acidity, stability, and pore size of the alumina directly influence lifetime and activity. Increased surface area and acidity, along with decreased pore size, lead to increased activity. However, these same characteristics also decrease lifetime. The properties of alumina are mutually dependent, and can be mutually opposed. Aluminas with better activity and longer life will result from a better understanding of these trends given the preparative method and thermal history.

  15. Modelling the initial stage of porous alumina growth during anodization

    NASA Astrophysics Data System (ADS)

    Aryslanova, E. M.; Alfimov, A. V.; Chivilikhin, S. A.

    2013-05-01

    Artificially on the surface of aluminum there may be build a thick layer of Al2O3, which has a porous structure. In this paper we present a model of growth of porous alumina in the initial stage of anodizing, identifying dependencies anodizing parameters on the rate of growth of the film and the distance between the pores and as a result of the created model equations were found for changes in the disturbance of alumina for the initial stage of anodizing aluminum oxide porous border aluminum-alumina and alumina-electrolyte, with the influence of surface diffusion of aluminum oxide.

  16. Exceptionally high levels of multiple mating in an army ant

    NASA Astrophysics Data System (ADS)

    Denny, A. Jay; Franks, Nigel R.; Powell, Scott; Edwards, Keith J.

    Most species of social insects have singly mated queens, although there are notable exceptions. Competing hypotheses have been proposed to explain the evolution of high levels of multiple mating, but this issue is far from resolved. Here we use microsatellites to investigate mating frequency in the army ant Eciton burchellii and show that queens mate with an exceptionally large number of males, eclipsing all but one other social insect species for which data are available. In addition we present evidence that suggests that mating is serial, continuing throughout the lifetime of the queen. This is the first demonstration of serial mating among social hymenoptera. We propose that high paternity within colonies is most likely to have evolved to increase genetic diversity and to counter high pathogen and parasite loads.

  17. ALICE: Project Overview and High Level Science Products

    NASA Astrophysics Data System (ADS)

    Soummer, Remi; Choquet, Elodie; Pueyo, Laurent; Brendan Hagan, J.; Gofas-Salas, Elena; Rajan, Abhijith; Perrin, Marshall D.; Chen, Christine; Debes, John H.; Golimowski, David A.; Hines, Dean C.; Schneider, Glenn; N'Diaye, Mamadou; Mawet, Dimitri; Marois, Christian; Barman, Travis

    2015-01-01

    We report on the status of the ALICE project (Archival Legacy Investigation of Circumstellar Environments), which consists in a consistent reanalysis of the entire HST-NICMOS coronagraphic archive. Over the last two years, we have developed a sophisticated pipeline able to handle the data of the 400 stars of the archive. This pipeline builds on the Karhunen-Loeve Image Projection (KLIP) algorithm, and was completed in the fall of 2014. We discuss the first processing and analysis results of the overall reduction campaign. As we will deliver high-level science products to the STScI MAST archive, we are defining a new standard format for high-contrast science products, which will be compatible with every new high-contrast imaging instrument (GPI, SPHERE, P1640, CHARIS, etc.) and used by the JWST coronagraphs. We present here the specifications of this standard.

  18. High Level Waste System Impacts from Acid Dissolution of Sludge

    SciTech Connect

    KETUSKY, EDWARD

    2006-04-20

    This research evaluates the ability of OLI{copyright} equilibrium based software to forecast Savannah River Site High Level Waste system impacts from oxalic acid dissolution of Tank 1-15 sludge heels. Without further laboratory and field testing, only the use of oxalic acid can be considered plausible to support sludge heel dissolution on multiple tanks. Using OLI{copyright} and available test results, a dissolution model is constructed and validated. Material and energy balances, coupled with the model, identify potential safety concerns. Overpressurization and overheating are shown to be unlikely. Corrosion induced hydrogen could, however, overwhelm the tank ventilation. While pH adjustment can restore the minimal hydrogen generation, resultant precipitates will notably increase the sludge volume. OLI{copyright} is used to develop a flowsheet such that additional sludge vitrification canisters and other negative system impacts are minimized. Sensitivity analyses are used to assess the processability impacts from variations in the sludge/quantities of acids.

  19. Using the CMS High Level Trigger as a Cloud Resource

    NASA Astrophysics Data System (ADS)

    Colling, David; Huffman, Adam; McCrae, Alison; Lahiff, Andrew; Grandi, Claudio; Cinquilli, Mattia; Gowdy, Stephen; Coarasa, Jose Antonio; Tiradani, Anthony; Ozga, Wojciech; Chaze, Olivier; Sgaravatto, Massimo; Bauer, Daniela

    2014-06-01

    The CMS High Level Trigger is a compute farm of more than 10,000 cores. During data taking this resource is heavily used and is an integral part of the experiment's triggering system. However, outside of data taking periods this resource is largely unused. We describe why CMS wants to use the HLT as a cloud resource (outside of data taking periods) and how this has been achieved. In doing this we have turned a single-use cluster into an agile resource for CMS production computing. While we are able to use the HLT as a production cloud resource, there is still considerable further work that CMS needs to carry out before this resource can be used with the desired agility. This report, therefore, represents a snapshot of this activity at the time of CHEP 2013.

  20. A High-Level Language for Rule-Based Modelling

    PubMed Central

    Pedersen, Michael; Phillips, Andrew; Plotkin, Gordon D.

    2015-01-01

    Rule-based languages such as Kappa excel in their support for handling the combinatorial complexities prevalent in many biological systems, including signalling pathways. But Kappa provides little structure for organising rules, and large models can therefore be hard to read and maintain. This paper introduces a high-level, modular extension of Kappa called LBS-κ. We demonstrate the constructs of the language through examples and three case studies: a chemotaxis switch ring, a MAPK cascade, and an insulin signalling pathway. We then provide a formal definition of LBS-κ through an abstract syntax and a translation to plain Kappa. The translation is implemented in a compiler tool which is available as a web application. We finally demonstrate how to increase the expressivity of LBS-κ through embedded scripts in a general-purpose programming language, a technique which we view as generally applicable to other domain specific languages. PMID:26043208

  1. SIMULANT DEVELOPMENT FOR SAVANNAH RIVER SITE HIGH LEVEL WASTE

    SciTech Connect

    Stone, M; Russell Eibling, R; David Koopman, D; Dan Lambert, D; Paul Burket, P

    2007-09-04

    The Defense Waste Processing Facility (DWPF) at the Savannah River Site vitrifies High Level Waste (HLW) for repository internment. The process consists of three major steps: waste pretreatment, vitrification, and canister decontamination/sealing. The HLW consists of insoluble metal hydroxides (primarily iron, aluminum, magnesium, manganese, and uranium) and soluble sodium salts (carbonate, hydroxide, nitrite, nitrate, and sulfate). The HLW is processed in large batches through DWPF; DWPF has recently completed processing Sludge Batch 3 (SB3) and is currently processing Sludge Batch 4 (SB4). The composition of metal species in SB4 is shown in Table 1 as a function of the ratio of a metal to iron. Simulants remove radioactive species and renormalize the remaining species. Supernate composition is shown in Table 2.

  2. Linearization of the Fermilab recycler high level RF

    SciTech Connect

    Joseph E Dey; Tom Kubicki; John Reid

    2003-05-28

    In studying the Recycler high level RF, it was found that at 89 kHz, the lowest frequency required by the system, some nonlinearities in magnitude and phase were discovered. The visible evidence of this was that beam injected in a barrier bucket had a definite slope at the top. Using a network analyzer, the S-parameter S{sub 21} was realized for the overall system and from mathematical modeling a second order numerator and denominator transfer function was found. The inverse of this transfer function gives their linearization transfer function. The linearization transfer function was realized in hardware by summing a high pass, band pass and low pass filter together. The resulting magnitude and phase plots, along with actual beam response will be shown.

  3. High level radioactive waste vitrification process equipment component testing

    SciTech Connect

    Siemens, D.H.; Heath, W.O.; Larson, D.E.; Craig, S.N.; Berger, D.N.; Goles, R.W.

    1985-04-01

    Remote operability and maintainability of vitrification equipment were assessed under shielded-cell conditions. The equipment tested will be applied to immobilize high-level and transuranic liquid waste slurries that resulted from plutonium production for defense weapons. Equipment tested included: a turntable for handling waste canisters under the melter; a removable discharge cone in the melter overflow section; a thermocouple jumper that extends into a shielded cell; remote instrument and electrical connectors; remote, mechanical, and heat transfer aspects of the melter glass overflow section; a reamer to clean out plugged nozzles in the melter top; a closed circuit camera to view the melter interior; and a device to retrieve samples of the glass product. A test was also conducted to evaluate liquid metals for use in a liquid metal sealing system.

  4. High-Level Language Production in Parkinson's Disease: A Review

    PubMed Central

    Altmann, Lori J. P.; Troche, Michelle S.

    2011-01-01

    This paper discusses impairments of high-level, complex language production in Parkinson's disease (PD), defined as sentence and discourse production, and situates these impairments within the framework of current psycholinguistic theories of language production. The paper comprises three major sections, an overview of the effects of PD on the brain and cognition, a review of the literature on language production in PD, and a discussion of the stages of the language production process that are impaired in PD. Overall, the literature converges on a few common characteristics of language production in PD: reduced information content, impaired grammaticality, disrupted fluency, and reduced syntactic complexity. Many studies also document the strong impact of differences in cognitive ability on language production. Based on the data, PD affects all stages of language production including conceptualization and functional and positional processing. Furthermore, impairments at all stages appear to be exacerbated by impairments in cognitive abilities. PMID:21860777

  5. Review of High Level Waste Tanks Ultrasonic Inspection Data

    SciTech Connect

    Wiersma, B

    2006-03-09

    A review of the data collected during ultrasonic inspection of the Type I high level waste tanks has been completed. The data was analyzed for relevance to the possibility of vapor space corrosion and liquid/air interface corrosion. The review of the Type I tank UT inspection data has confirmed that the vapor space general corrosion is not an unusually aggressive phenomena and correlates well with predicted corrosion rates for steel exposed to bulk solution. The corrosion rates are seen to decrease with time as expected. The review of the temperature data did not reveal any obvious correlations between high temperatures and the occurrences of leaks. The complex nature of temperature-humidity interaction, particularly with respect to vapor corrosion requires further understanding to infer any correlation. The review of the waste level data also did not reveal any obvious correlations.

  6. 4.5 Meter high level waste canister study

    SciTech Connect

    Calmus, R. B.

    1997-10-01

    The Tank Waste Remediation System (TWRS) Storage and Disposal Project has established the Immobilized High-Level Waste (IBLW) Storage Sub-Project to provide the capability to store Phase I and II BLW products generated by private vendors. A design/construction project, Project W-464, was established under the Sub-Project to provide the Phase I capability. Project W-464 will retrofit the Hanford Site Canister Storage Building (CSB) to accommodate the Phase I I-ILW products. Project W-464 conceptual design is currently being performed to interim store 3.0 m-long BLW stainless steel canisters with a 0.61 in diameter, DOE is considering using a 4.5 in canister of the same diameter to reduce permanent disposal costs. This study was performed to assess the impact of replacing the 3.0 in canister with the 4.5 in canister. The summary cost and schedule impacts are described.

  7. Midwestern High-Level Radioactive Waste Transportation Project

    SciTech Connect

    Dantoin, T.S.

    1990-12-01

    For more than half a century, the Council of State Governments has served as a common ground for the states of the nation. The Council is a nonprofit, state-supported and -directed service organization that provides research and resources, identifies trends, supplies answers and creates a network for legislative, executive and judicial branch representatives. This List of Available Resources was prepared with the support of the US Department of Energy, Cooperative Agreement No. DE-FC02-89CH10402. However, any opinions, findings, conclusions, or recommendations expressed herein are those of the author(s) and do not necessarily reflect the views of DOE. The purpose of the agreement, and reports issued pursuant to it, is to identify and analyze regional issues pertaining to the transportation of high-level radioactive waste and to inform Midwestern state officials with respect to technical issues and regulatory concerns related to waste transportation.

  8. Calculates Neutron Production in Canisters of High-level Waste

    Energy Science and Technology Software Center (ESTSC)

    1993-01-15

    ALPHN calculates the (alpha,n) neutron production rate of a canister of vitrified high-level waste. The user supplies the chemical composition of the glass or glass-ceramic and the curies of the alpha-emitting actinides present. The output of the program gives the (alpha,n) neutron production of each actinide in neutrons per second and the total for the canister. The (alpha,n) neutron production rates are source terms only; that is, they are production rates within the glass andmore » do not take into account the shielding effect of the glass. For a given glass composition, the user can calculate up to eight cases simultaneously; these cases are based on the same glass composition but contain different quantities of actinides per canister.« less

  9. A high-level language for rule-based modelling.

    PubMed

    Pedersen, Michael; Phillips, Andrew; Plotkin, Gordon D

    2015-01-01

    Rule-based languages such as Kappa excel in their support for handling the combinatorial complexities prevalent in many biological systems, including signalling pathways. But Kappa provides little structure for organising rules, and large models can therefore be hard to read and maintain. This paper introduces a high-level, modular extension of Kappa called LBS-κ. We demonstrate the constructs of the language through examples and three case studies: a chemotaxis switch ring, a MAPK cascade, and an insulin signalling pathway. We then provide a formal definition of LBS-κ through an abstract syntax and a translation to plain Kappa. The translation is implemented in a compiler tool which is available as a web application. We finally demonstrate how to increase the expressivity of LBS-κ through embedded scripts in a general-purpose programming language, a technique which we view as generally applicable to other domain specific languages. PMID:26043208

  10. High Level Information Fusion (HLIF) with nested fusion loops

    NASA Astrophysics Data System (ADS)

    Woodley, Robert; Gosnell, Michael; Fischer, Amber

    2013-05-01

    Situation modeling and threat prediction require higher levels of data fusion in order to provide actionable information. Beyond the sensor data and sources the analyst has access to, the use of out-sourced and re-sourced data is becoming common. Through the years, some common frameworks have emerged for dealing with information fusion—perhaps the most ubiquitous being the JDL Data Fusion Group and their initial 4-level data fusion model. Since these initial developments, numerous models of information fusion have emerged, hoping to better capture the human-centric process of data analyses within a machine-centric framework. 21st Century Systems, Inc. has developed Fusion with Uncertainty Reasoning using Nested Assessment Characterizer Elements (FURNACE) to address challenges of high level information fusion and handle bias, ambiguity, and uncertainty (BAU) for Situation Modeling, Threat Modeling, and Threat Prediction. It combines JDL fusion levels with nested fusion loops and state-of-the-art data reasoning. Initial research has shown that FURNACE is able to reduce BAU and improve the fusion process by allowing high level information fusion (HLIF) to affect lower levels without the double counting of information or other biasing issues. The initial FURNACE project was focused on the underlying algorithms to produce a fusion system able to handle BAU and repurposed data in a cohesive manner. FURNACE supports analyst's efforts to develop situation models, threat models, and threat predictions to increase situational awareness of the battlespace. FURNACE will not only revolutionize the military intelligence realm, but also benefit the larger homeland defense, law enforcement, and business intelligence markets.

  11. High-level waste program integration within the DOE complex

    SciTech Connect

    Valentine, J.H.; Davis, N.R.; Malone, K.; Schaus, P.S.

    1998-03-01

    Eleven major Department of Energy (DOE) site contractors were chartered by the Assistant Secretary to use a systems engineering approach to develop and evaluate technically defensible cost savings opportunities across the complex. Known as the complex-wide Environmental Management Integration (EMI), this process evaluated all the major DOE waste streams including high level waste (HLW). Across the DOE complex, this waste stream has the highest life cycle cost and is scheduled to take until at least 2035 before all HLW is processed for disposal. Technical contract experts from the four DOE sites that manage high level waste participated in the integration analysis: Hanford, Savannah River Site (SRS), Idaho National Engineering and Environmental Laboratory (INEEL), and West Valley Demonstration Project (WVDP). In addition, subject matter experts from the Yucca Mountain Project and the Tanks Focus Area participated in the analysis. Also, departmental representatives from the US Department of Energy Headquarters (DOE-HQ) monitored the analysis and results. Workouts were held throughout the year to develop recommendations to achieve a complex-wide integrated program. From this effort, the HLW Environmental Management (EM) Team identified a set of programmatic and technical opportunities that could result in potential cost savings and avoidance in excess of $18 billion and an accelerated completion of the HLW mission by seven years. The cost savings, schedule improvements, and volume reduction are attributed to a multifaceted HLW treatment disposal strategy which involves waste pretreatment, standardized waste matrices, risk-based retrieval, early development and deployment of a shipping system for glass canisters, and reasonable, low cost tank closure.

  12. Reevaluation Of Vitrified High-Level Waste Form Criteria For Potential Cost Savings At The Defense Waste Processing Facility

    SciTech Connect

    Ray, J. W.; Marra, S. L.; Herman, C. C.

    2013-01-09

    At the Savannah River Site (SRS) the Defense Waste Processing Facility (DWPF) has been immobilizing SRS's radioactive high level waste (HLW) sludge into a durable borosilicate glass since 1996. Currently the DWPF has poured over 3,500 canisters, all of which are compliant with the U. S. Department of Energy's (DOE) Waste Acceptance Product Specifications for Vitrified High-Level Waste Forms (WAPS) and therefore ready to be shipped to a federal geologic repository for permanent disposal. Due to DOE petitioning to withdraw the Yucca Mountain License Application (LA) from the Nuclear Regulatory Commission (NRC) in 2010 and thus no clear disposal path for SRS canistered waste forms, there are opportunities for cost savings with future canister production at DWPF and other DOE producer sites by reevaluating high-level waste form requirements and compliance strategies and reducing/eliminating those that will not negatively impact the quality of the canistered waste form.

  13. Reevaluation of Vitrified High-Level Waste Form Criteria for Potential Cost Savings at the Defense Waste Processing Facility - 13598

    SciTech Connect

    Ray, J.W.; Marra, S.L.; Herman, C.C.

    2013-07-01

    At the Savannah River Site (SRS) the Defense Waste Processing Facility (DWPF) has been immobilizing SRS's radioactive high level waste (HLW) sludge into a durable borosilicate glass since 1996. Currently the DWPF has poured over 3,500 canisters, all of which are compliant with the U. S. Department of Energy's (DOE) Waste Acceptance Product Specifications for Vitrified High-Level Waste Forms (WAPS) and therefore ready to be shipped to a federal geologic repository for permanent disposal. Due to DOE petitioning to withdraw the Yucca Mountain License Application (LA) from the Nuclear Regulatory Commission (NRC) in 2010 and thus no clear disposal path for SRS canistered waste forms, there are opportunities for cost savings with future canister production at DWPF and other DOE producer sites by reevaluating high-level waste form requirements and compliance strategies and reducing/eliminating those that will not negatively impact the quality of the canistered waste form. (authors)

  14. DESIGN ANALYSIS FOR THE DEFENSE HIGH-LEVEL WASTE DISPOSAL CONTAINER

    SciTech Connect

    G. Radulesscu; J.S. Tang

    2000-06-07

    The purpose of ''Design Analysis for the Defense High-Level Waste Disposal Container'' analysis is to technically define the defense high-level waste (DHLW) disposal container/waste package using the Waste Package Department's (WPD) design methods, as documented in ''Waste Package Design Methodology Report'' (CRWMS M&O [Civilian Radioactive Waste Management System Management and Operating Contractor] 2000a). The DHLW disposal container is intended for disposal of commercial high-level waste (HLW) and DHLW (including immobilized plutonium waste forms), placed within disposable canisters. The U.S. Department of Energy (DOE)-managed spent nuclear fuel (SNF) in disposable canisters may also be placed in a DHLW disposal container along with HLW forms. The objective of this analysis is to demonstrate that the DHLW disposal container/waste package satisfies the project requirements, as embodied in Defense High Level Waste Disposal Container System Description Document (SDD) (CRWMS M&O 1999a), and additional criteria, as identified in Waste Package Design Sensitivity Report (CRWMS M&Q 2000b, Table 4). The analysis briefly describes the analytical methods appropriate for the design of the DHLW disposal contained waste package, and summarizes the results of the calculations that illustrate the analytical methods. However, the analysis is limited to the calculations selected for the DHLW disposal container in support of the Site Recommendation (SR) (CRWMS M&O 2000b, Section 7). The scope of this analysis is restricted to the design of the codisposal waste package of the Savannah River Site (SRS) DHLW glass canisters and the Training, Research, Isotopes General Atomics (TRIGA) SNF loaded in a short 18-in.-outer diameter (OD) DOE standardized SNF canister. This waste package is representative of the waste packages that consist of the DHLW disposal container, the DHLW/HLW glass canisters, and the DOE-managed SNF in disposable canisters. The intended use of this analysis is to

  15. 10 CFR 72.128 - Criteria for spent fuel, high-level radioactive waste, reactor-related greater than Class C waste...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 2 2011-01-01 2011-01-01 false Criteria for spent fuel, high-level radioactive waste, reactor-related greater than Class C waste, and other radioactive waste storage and handling. 72.128 Section 72.128 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSING REQUIREMENTS FOR THE INDEPENDENT STORAGE OF SPENT NUCLEAR FUEL,...

  16. Crystalline plutonium hosts derived from high-level waste formulations.

    SciTech Connect

    O'Holleran, T. P.

    1998-04-24

    The Department of Energy has selected immobilization for disposal in a repository as one approach for disposing of excess plutonium (1). Materials for immobilizing weapons-grade plutonium for repository disposal must meet the ''spent fuel standard'' by providing a radiation field similar to spent fuel (2). Such a radiation field can be provided by incorporating fission products from high-level waste into the waste form. Experiments were performed to evaluate the feasibility of incorporating high-level waste (HLW) stored at the Idaho Chemical Processing Plant (ICPP) into plutonium dispositioning materials to meet the spent fuel standard. A variety of materials and preparation techniques were evaluated based on prior experience developing waste forms for immobilizing HLW. These included crystalline ceramic compositions prepared by conventional sintering and hot isostatic pressing (HIP), and glass formulations prepared by conventional melting. Because plutonium solubility in silicate melts is limited, glass formulations were intentionally devitrified to partition plutonium into crystalline host phases, thereby allowing increased overall plutonium loading. Samarium, added as a representative rare earth neutron absorber, also tended to partition into the plutonium host phases. Because the crystalline plutonium host phases are chemically more inert, the plutonium is more effectively isolated from the environment, and its attractiveness for proliferation is reduced. In the initial phase of evaluating each material and preparation method, cerium was used as a surrogate for plutonium. For promising materials, additional preparation experiments were performed using plutonium to verify the behavior of cerium as a surrogate. These experiments demonstrated that cerium performed well as a surrogate for plutonium. For the most part, cerium and plutonium partitioned onto the same crystalline phases, and no anomalous changes in oxidation state were observed. The only observed

  17. CEMENTITIOUS GROUT FOR CLOSING SRS HIGH LEVEL WASTE TANKS - #12315

    SciTech Connect

    Langton, C.; Burns, H.; Stefanko, D.

    2012-01-10

    In 1997, the first two United States Department of Energy (US DOE) high level waste tanks (Tanks 17-F and 20-F: Type IV, single shell tanks) were taken out of service (permanently closed) at the Savannah River Site (SRS). In 2012, the DOE plans to remove from service two additional Savannah River Site (SRS) Type IV high-level waste tanks, Tanks 18-F and 19-F. These tanks were constructed in the late 1950's and received low-heat waste and do not contain cooling coils. Operational closure of Tanks 18-F and 19-F is intended to be consistent with the applicable requirements of the Resource Conservation and Recovery Act (RCRA) and the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) and will be performed in accordance with South Carolina Department of Health and Environmental Control (SCDHEC). The closure will physically stabilize two 4.92E+04 cubic meter (1.3 E+06 gallon) carbon steel tanks and isolate and stabilize any residual contaminants left in the tanks. The closure will also fill, physically stabilize and isolate ancillary equipment abandoned in the tanks. A Performance Assessment (PA) has been developed to assess the long-term fate and transport of residual contamination in the environment resulting from the operational closure of the F-Area Tank Farm (FTF) waste tanks. Next generation flowable, zero-bleed cementitious grouts were designed, tested, and specified for closing Tanks 18-F and 19-F and for filling the abandoned equipment. Fill requirements were developed for both the tank and equipment grouts. All grout formulations were required to be alkaline with a pH of 12.4 and chemically reduction potential (Eh) of -200 to -400 to stabilize selected potential contaminants of concern. This was achieved by including Portland cement and Grade 100 slag in the mixes, respectively. Ingredients and proportions of cementitious reagents were selected and adjusted, respectively, to support the mass placement strategy developed by closure

  18. Interventions for Individuals With High Levels of Needle Fear

    PubMed Central

    Noel, Melanie; Taddio, Anna; Antony, Martin M.; Asmundson, Gordon J.G.; Riddell, Rebecca Pillai; Chambers, Christine T.; Shah, Vibhuti

    2015-01-01

    Background: This systematic review evaluated the effectiveness of exposure-based psychological and physical interventions for the management of high levels of needle fear and/or phobia and fainting in children and adults. Design/Methods: A systematic review identified relevant randomized and quasi-randomized controlled trials of children, adults, or both with high levels of needle fear, including phobia (if not available, then populations with other specific phobias were included). Critically important outcomes were self-reported fear specific to the feared situation and stimulus (psychological interventions) or fainting (applied muscle tension). Data were pooled using standardized mean difference (SMD) or relative risk with 95% confidence intervals. Results: The systematic review included 11 trials. In vivo exposure-based therapy for children 7 years and above showed benefit on specific fear (n=234; SMD: −1.71 [95% CI: −2.72, −0.7]). In vivo exposure-based therapy with adults reduced fear of needles posttreatment (n=20; SMD: −1.09 [−2.04, −0.14]) but not at 1-year follow-up (n=20; SMD: −0.28 [−1.16, 0.6]). Compared with single session, a benefit was observed for multiple sessions of exposure-based therapy posttreatment (n=93; SMD: −0.66 [−1.08, −0.24]) but not after 1 year (n=83; SMD: −0.37 [−0.87, 0.13]). Non in vivo e.g., imaginal exposure-based therapy in children reduced specific fear posttreatment (n=41; SMD: −0.88 [−1.7, −0.05]) and at 3 months (n=24; SMD: −0.89 [−1.73, −0.04]). Non in vivo exposure-based therapy for adults showed benefit on specific fear (n=68; SMD: −0.62 [−1.11, −0.14]) but not procedural fear (n=17; SMD: 0.18 [−0.87, 1.23]). Applied tension showed benefit on fainting posttreatment (n=20; SMD: −1.16 [−2.12, −0.19]) and after 1 year (n=20; SMD: −0.97 [−1.91, −0.03]) compared with exposure alone. Conclusions: Exposure-based psychological interventions and applied muscle tension show

  19. Anisotropic shrinkage characteristics of tape cast alumina

    NASA Astrophysics Data System (ADS)

    Patwardhan, Jaideep Suresh

    Dimensional control during sintering is a major issue in ceramics processing to avoid high post-sintering costs associated with machining of the fired ceramic part to desired tolerances and dimensions. Ceramic forming processes such as tape casting, injection molding, and extrusion involve shear of anisotropic particles resulting in preferential alignment of the particles in the green body. This preferential alignment causes directionality in mechanical, electrical, optical, and magnetic properties and most importantly warpage or distortion during sintering. A large effort has been devoted to synthesizing ceramic green bodies with minimal density gradients and uniform packing and modeling the sintering behavior evolution but little effort has been devoted to characterizing orientation of particles and the effect of preferential alignment on sintering shrinkage anisotropy. A systematic study was initiated to study the effect of processing variables such as shear rate, solids loading, temperature, and binder content on aqueous tape cast alumina. Three different alumina systems: A16-SG, Baikowski RC-UFX DBM and RC-LS DBM were investigated. Aqueous tapes of high solids loading alumina (56 vol. %) were tape cast at various speeds and thicknesses and assuming plane Couette flow a shear rate regime of 21--270 s-1 was investigated. Higher shear rates and high solids loading resulted in higher in-plane anisotropy whereas the anisotropy in the thickness direction was higher for low solids loading systems. The anisotropy was found to be fairly constant above a certain critical shear rate (˜100 s-1) irrespective of the temperature and the solids loading and this correlated with the viscosity-shear rate relationship of the cast slips. The higher shrinkage anisotropy in the thickness direction for the low solids loading systems (35 and 45 vol. %) was attributed to the higher amount of organics in the slip required to sustain the suitable viscosity for tape casting and

  20. Intercalation of water into lithium. beta. -alumina

    SciTech Connect

    Dudney, N J; Bates, J B; Wang, J C; Brown, G M; Larson, B C; Engstrom, H

    1981-01-01

    Infrared absorption, neutron diffraction and weight loss techniques have been used to investigate the hydration of single crystals of Li ..beta..-alumina. The hydration is a reversible intercalation reaction. Up to approximately two water molecules per formula unit can penetrate the conduction plane. Other protonated species are formed from the dissociation of the molecular water. The rate of hydration is controlled by the diffusion of water in the conduction plane. A likely diffusion mechanism requires dissociation of the water and an interstitialcy motion of the oxygen.

  1. Porosity in plasma sprayed alumina coatings

    SciTech Connect

    Ilavsky, J.; Herman, H.; Berndt, C.C.; Goland, A.N.; Long, G.G.; Krueger, S.; Allen, A.J.

    1994-03-01

    Small-angle neutron scattering (SANS) was used to study the porosity of plasma sprayed deposits of alumina in as-sprayed and heat-treated conditions. SANS results were compared with mercury intrusion porosimetry (MIP) and water immersion techniques. Multiple small-angle neutron scattering yields a volume-weighted effective pore radius (R{sub eff}), for pores with sizes between 0.08 and 10{mu}m, the pore volume in this size region, and from the Porod region, the surface area of pores of all sizes.

  2. Crack growth resistance of textured alumina

    NASA Technical Reports Server (NTRS)

    Salem, Jonathan A.; Shannon, John L., Jr.; Bradt, Richard C.

    1989-01-01

    The crack growth resistance of a textured, extruded alumina body was compared with that of anisotropic, isopressed body of similar grain size, density, and chemistry. R-curve levels reflected the preferred orientation; however, R-curve slopes were the same in all instances, implying a similar crack growth-resistive mechanism. Three orthogonal orientations of crack growth in the two structures exhibited similar forms of K(IR) versus Delta-a curves, for which a schematic diagram for polycrystalline ceramics is proposed.

  3. Conduction mechanism of single-crystal alumina

    NASA Technical Reports Server (NTRS)

    Will, Fritz G.; Delorenzi, Horst G.; Janora, Kevin H.

    1992-01-01

    The fully guarded three-terminal technique was used to perform conductivity measurements on single-crystal alumina at temperatures of 400-1300 C. The conductivity was also determined as a function of time at various temperatures and applied fields. Further, the fractions of the current carried by Al and O ions (ionic transference numbers) were determined from long-term transference experiments in the temperature range 1100-1300 C. A mathematical model of the conduction mechanism is proposed, and model predictions are compared with experimental results.

  4. Improved Synthesis Of Potassium Beta' '-Alumina

    NASA Technical Reports Server (NTRS)

    Williams, Roger M.; Jeffries-Nakamura, Barbara; Ryan, Margaret A.; O'Connor, Dennis E.; Kisor, Adam; Underwood, Mark

    1996-01-01

    Improved formulations of precursor materials synthesize nearly-phase-pure potassium beta' '-alumina solid electrolyte (K-BASE) powder. Materials are microhomogeneous powders (or, alternatively, gels) containing K(+,) Mg(2+), and Al(3+). K-BASE powder produced used in potassium-working-fluid alkali-metal thermal-to-electric conversion (K-AMTEC), in which heat-input and heat-rejection temperatures lower than sodium-working-fluid AMTEC (Na-AMTEC). Additional potential use lies in purification of pottassium by removal of sodium and calcium.

  5. Preconceptual design study for solidifying high-level waste: Appendices A, B and C West Valley Demonstration Project

    SciTech Connect

    Hill, O.F.

    1981-04-01

    This report presents a preconceptual design study for processing radioactive high-level liquid waste presently stored in underground tanks at Western New York Nuclear Service Center (WNYNSC) near West Valley, New York, and for incorporating the radionculides in that waste into a solid. The high-level liquid waste accumulated from the operation of a chemical reprocessing plant by the Nuclear Fuel Services, Inc. from 1966 to 1972. The high-level liquid waste consists of approximately 560,000 gallons of alkaline waste from Purex process operations and 12,000 gallons of acidic (nitric acid) waste from one campaign of processing thoria fuels by a modified Thorex process (during this campaign thorium was left in the waste). The alkaline waste contains approximately 30 million curies and the acidic waste contains approximately 2.5 million curies. The reference process described in this report is concerned only with chemically processing the high-level liquid waste to remove radionuclides from the alkaline supernate and converting the radionuclide-containing nonsalt components in the waste into a borosilicate glass.

  6. Role of Congress in the High Level Radioactive Waste Odyssey: The Wisdom and Will of the Congress - 13096

    SciTech Connect

    Vieth, Donald L.

    2013-07-01

    Congress has had a dual role with regard to high level radioactive waste, being involved in both its creation and its disposal. A significant amount of time has passed between the creation of the nation's first high level radioactive waste and the present day. The pace of addressing its remediation has been highly irregular. Congress has had to consider the technical, regulatory, and political issues and all have had specific difficulties. It is a true odyssey framed by an imperative and accountability, by a sense of urgency, by an ability or inability to finish the job and by consequences. Congress had set a politically acceptable course by 1982. However, President Obama intervened in the process after he took office in January 2009. Through the efforts of his Administration, by the end of 2012, the US government has no program to dispose of high level radioactive waste and no reasonable prospect of a repository for high level radioactive waste. It is not obvious how the US government program will be reestablished or who will assume responsibility for leadership. The ultimate criteria for judging the consequences are 1) the outcome of the ongoing NRC's Nuclear Waste Confidence Rulemaking and 2) the concomitant permissibility of nuclear energy supplying electricity from operating reactors in the US. (authors)

  7. High-level waste disposal, ethics and thermodynamics

    NASA Astrophysics Data System (ADS)

    Schwartz, Michael O.

    2008-06-01

    Moral philosophy applied to nuclear waste disposal can be linked to paradigmatic science. Simple thermodynamic principles tell us something about rightness or wrongness of our action. Ethical judgement can be orientated towards the chemical compatibility between waste container and geological repository. A container-repository system as close as possible to thermodynamic equilibrium is ethically acceptable. It aims at unlimited stability, similar to the stability of natural metal deposits within the Earth’s crust. The practicability of the guideline can be demonstrated.

  8. Microstructural and Mechanical Characterization of Actively Brazed Alumina Specimens

    SciTech Connect

    Hosking, F.M.; Cadden, C.H.; Stephens, J.J.; Glass, S.J.; Yang, N.Y.C.; Vianco, P.V.; Walker, C.A.

    1999-08-26

    Alumina (94 and 99.8% grade compositions) was brazed directly to itself with gold-based active brazing alloys (ABA's) containing vanadium additions of 1,2 and 3 weight percent. The effects of brazing conditions on the joint properties were investigated. Wetting behavior, interfacial reactions, microstructure, hermeticity and tensile strength were determined. Wetting was fair to good for the ABA and base material combinations. Microanalysis identified a discontinuous Al-V-O spinel reaction product at the alumina-braze interface. Tensile strength results for 94% alumina were uniformly good and generally not sensitive to the vanadium concentration, with tensile values of 85-105 MPa. There was more variability in the 99.8% alumina strength results, with values ranging from 25-95 MPa. The highest vanadium concentration (3 wt. %) yielded the highest joint strength for the brazed 99.8% alumina. Failures in the 99.8% alumina samples occurred at the braze-alumina interface, while the 94% alumina specimens exhibited fracture of the ceramic substrate.

  9. Dynamic compressive and tensile strengths of spark plasma sintered alumina

    NASA Astrophysics Data System (ADS)

    Girlitsky, I.; Zaretsky, E.; Kalabukhov, S.; Dariel, M. P.; Frage, N.

    2014-06-01

    Fully dense submicron grain size alumina samples were manufactured from alumina nano-powder using Spark Plasma Sintering and tested in two kinds of VISAR-instrumented planar impact tests. In the first kind, samples were loaded by 1-mm tungsten impactors, accelerated to a velocity of about 1 km/s. These tests were aimed at studying the Hugoniot elastic limit (HEL) of Spark Plasma Sintering (SPS)-processed alumina and the decay, with propagation distance, of the elastic precursor wave. In the tests of the second kind, alumina samples of 3-mm thickness were loaded by 1-mm copper impactors accelerated to 100-1000 m/s. These tests were aimed at studying the dynamic tensile (spall) strength of the alumina specimens. The tensile fracture of the un-alloyed alumina shows a monotonic decline of the spall strength with the amplitude of the loading stress pulse. Analysis of the decay of the elastic precursor wave allowed determining the rate of the irreversible (inelastic) strains in the SPS-processed alumina at the initial stages of the shock-induced inelastic deformation and to clarify the mechanisms responsible for the deformation. The 1-% addition of Cr2O3 decreases the HEL of the SPS-processed alumina by 5-% and its spall strength by 50% but barely affects its static properties.

  10. Depositing Adherent Ag Films On Ti Films On Alumina

    NASA Technical Reports Server (NTRS)

    Honecy, Frank S.

    1995-01-01

    Report discusses cleaning of ceramic (principally, alumina) substrates in preparation for sputter deposition of titanium intermediate films on substrates followed by sputter deposition of outer silver films. Principal intended application, substrates sliding parts in advanced high-temperature heat engines, and outer silver films serve as solid lubricants: lubricating properties described in "Solid Lubricant for Alumina" (LEW-15495).

  11. Dynamic compressive and tensile strengths of spark plasma sintered alumina

    SciTech Connect

    Girlitsky, I.; Zaretsky, E.; Kalabukhov, S.; Dariel, M. P.; Frage, N.

    2014-06-28

    Fully dense submicron grain size alumina samples were manufactured from alumina nano-powder using Spark Plasma Sintering and tested in two kinds of VISAR-instrumented planar impact tests. In the first kind, samples were loaded by 1-mm tungsten impactors, accelerated to a velocity of about 1 km/s. These tests were aimed at studying the Hugoniot elastic limit (HEL) of Spark Plasma Sintering (SPS)-processed alumina and the decay, with propagation distance, of the elastic precursor wave. In the tests of the second kind, alumina samples of 3-mm thickness were loaded by 1-mm copper impactors accelerated to 100–1000 m/s. These tests were aimed at studying the dynamic tensile (spall) strength of the alumina specimens. The tensile fracture of the un-alloyed alumina shows a monotonic decline of the spall strength with the amplitude of the loading stress pulse. Analysis of the decay of the elastic precursor wave allowed determining the rate of the irreversible (inelastic) strains in the SPS-processed alumina at the initial stages of the shock-induced inelastic deformation and to clarify the mechanisms responsible for the deformation. The 1-% addition of Cr{sub 2}O{sub 3} decreases the HEL of the SPS-processed alumina by 5-% and its spall strength by 50% but barely affects its static properties.

  12. Process for the recovery of alumina from fly ash

    DOEpatents

    Murtha, M.J.

    1983-08-09

    An improvement in the lime-sinter process for recovering alumina from pulverized coal fly ash is disclosed. The addition of from 2 to 10 weight percent carbon and sulfur to the fly ash-calcium carbonate mixture increase alumina recovery at lower sintering temperatures.

  13. 40 CFR 721.10120 - Siloxane modified alumina nanoparticles (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... nanoparticles (generic). 721.10120 Section 721.10120 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.10120 Siloxane modified alumina nanoparticles (generic). (a) Chemical... as siloxane modified alumina nanoparticles (PMN P-05-687) is subject to reporting under this...

  14. 40 CFR 721.10120 - Siloxane modified alumina nanoparticles (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... nanoparticles (generic). 721.10120 Section 721.10120 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.10120 Siloxane modified alumina nanoparticles (generic). (a) Chemical... as siloxane modified alumina nanoparticles (PMN P-05-687) is subject to reporting under this...

  15. High-Level Performance Modeling of SAR Systems

    NASA Technical Reports Server (NTRS)

    Chen, Curtis

    2006-01-01

    SAUSAGE (Still Another Utility for SAR Analysis that s General and Extensible) is a computer program for modeling (see figure) the performance of synthetic- aperture radar (SAR) or interferometric synthetic-aperture radar (InSAR or IFSAR) systems. The user is assumed to be familiar with the basic principles of SAR imaging and interferometry. Given design parameters (e.g., altitude, power, and bandwidth) that characterize a radar system, the software predicts various performance metrics (e.g., signal-to-noise ratio and resolution). SAUSAGE is intended to be a general software tool for quick, high-level evaluation of radar designs; it is not meant to capture all the subtleties, nuances, and particulars of specific systems. SAUSAGE was written to facilitate the exploration of engineering tradeoffs within the multidimensional space of design parameters. Typically, this space is examined through an iterative process of adjusting the values of the design parameters and examining the effects of the adjustments on the overall performance of the system at each iteration. The software is designed to be modular and extensible to enable consideration of a variety of operating modes and antenna beam patterns, including, for example, strip-map and spotlight SAR acquisitions, polarimetry, burst modes, and squinted geometries.

  16. THERMAL ANALYSIS OF GEOLOGIC HIGH-LEVEL RADIOACTIVE WASTE PACKAGES

    SciTech Connect

    Hensel, S.; Lee, S.

    2010-04-20

    The engineering design of disposal of the high level waste (HLW) packages in a geologic repository requires a thermal analysis to provide the temperature history of the packages. Calculated temperatures are used to demonstrate compliance with criteria for waste acceptance into the geologic disposal gallery system and as input to assess the transient thermal characteristics of the vitrified HLW Package. The objective of the work was to evaluate the thermal performance of the supercontainer containing the vitrified HLW in a non-backfilled and unventilated underground disposal gallery. In order to achieve the objective, transient computational models for a geologic vitrified HLW package were developed by using a computational fluid dynamics method, and calculations for the HLW disposal gallery of the current Belgian geological repository reference design were performed. An initial two-dimensional model was used to conduct some parametric sensitivity studies to better understand the geologic system's thermal response. The effect of heat decay, number of co-disposed supercontainers, domain size, humidity, thermal conductivity and thermal emissivity were studied. Later, a more accurate three-dimensional model was developed by considering the conduction-convection cooling mechanism coupled with radiation, and the effect of the number of supercontainers (3, 4 and 8) was studied in more detail, as well as a bounding case with zero heat flux at both ends. The modeling methodology and results of the sensitivity studies will be presented.

  17. PLUTONIUM/HIGH-LEVEL VITRIFIED WASTE BDBE DOSE CALCULATION

    SciTech Connect

    J.A. Ziegler

    2000-11-20

    The purpose of this calculation is to provide a dose consequence analysis of high-level waste (HLW) consisting of plutonium immobilized in vitrified HLW to be handled at the proposed Monitored Geologic Repository at Yucca Mountain for a beyond design basis event (BDBE) under expected conditions using best estimate values for each calculation parameter. In addition to the dose calculation, a plutonium respirable particle size for dose calculation use is derived. The current concept for this waste form is plutonium disks enclosed in cans immobilized in canisters of vitrified HLW (i.e., glass). The plutonium inventory at risk used for this calculation is selected from Plutonium Immobilization Project Input for Yucca Mountain Total Systems Performance Assessment (Shaw 1999). The BDBE examined in this calculation is a nonmechanistic initiating event and the sequence of events that follow to cause a radiological release. This analysis will provide the radiological releases and dose consequences for a postulated BDBE. Results may be considered in other analyses to determine or modify the safety classification and quality assurance level of repository structures, systems, and components. This calculation uses best available technical information because the BDBE frequency is very low (i.e., less than 1.0E-6 events/year) and is not required for License Application for the Monitored Geologic Repository. The results of this calculation will not be used as part of a licensing or design basis.

  18. Ultrafilter Conditions for High Level Waste Sludge Processing

    SciTech Connect

    Geeting, John GH; Hallen, Richard T.; Peterson, Reid A.

    2006-08-28

    An evaluation of the optimal filtration conditions was performed based on test data obtained from filtration of a High Level Waste Sludge sample from the Hanford tank farms. This evaluation was performed using the anticipated configuration for the Waste Treatment Plant at the Hanford site. Testing was performed to identify the optimal pressure drop and cross flow velocity for filtration at both high and low solids loading. However, this analysis indicates that the actual filtration rate achieved is relatively insensitive to these conditions under anticipated operating conditions. The maximum filter flux was obtained by adjusting the system control valve pressure from 400 to 650 kPa while the filter feed concentration increased from 5 to 20 wt%. However, operating the system with a constant control valve pressure drop of 500 kPa resulted in a less than 1% reduction in the average filter flux. Also note that allowing the control valve pressure to swing as much as +/- 20% resulted in less than a 5% decrease in filter flux.

  19. Wind resource quality affected by high levels of renewables

    DOE PAGESBeta

    Diakov, Victor

    2015-06-17

    For solar photovoltaic (PV) and wind resources, the capacity factor is an important parameter describing the quality of the resource. As the share of variable renewable resources (such as PV and wind) on the electric system is increasing, so does curtailment (and the fraction of time when it cannot be avoided). At high levels of renewable generation, curtailments effectively change the practical measure of resource quality from capacity factor to the incremental capacity factor. The latter accounts only for generation during hours of no curtailment and is directly connected with the marginal capital cost of renewable generators for a givenmore » level of renewable generation during the year. The Western U.S. wind generation is analyzed hourly for a system with 75% of annual generation from wind, and it is found that the value for the system of resources with equal capacity factors can vary by a factor of 2, which highlights the importance of using the incremental capacity factor instead. Finally, the effect is expected to be more pronounced in smaller geographic areas (or when transmission limitations imposed) and less pronounced at lower levels of renewable energy in the system with less curtailment.« less

  20. High Level Waste Feed Certification in Hanford Double Shell Tanks

    SciTech Connect

    Thien, Micheal G.; Wells, Beric E.; Adamson, Duane J.

    2010-03-01

    The ability to effectively mix, sample, certify, and deliver consistent batches of High Level Waste (HLW) feed from the Hanford Double Shell Tanks (DST) to the Waste Treatment and Immobilization Plant (WTP) presents a significant mission risk with potential to impact mission length and the quantity of HLW glass produced. DOE’s River Protection Project (RPP) mission modeling and WTP facility modeling assume that individual 3785 cubic meter (1 million gallon) HLW feed tanks are homogenously mixed, representatively sampled, and consistently delivered to the WTP. It has been demonstrated that homogenous mixing of HLW sludge in Hanford DSTs is not likely achievable with the baseline design thereby causing representative sampling and consistent feed delivery to be more difficult. Inconsistent feed to the WTP could cause additional batch to batch operational adjustments that reduces operating efficiency and has the potential to increase the overall mission length. The Hanford mixing and sampling demonstration program will identify DST mixing performance capability, will evaluate representative sampling techniques, and will estimate feed batch consistency. An evaluation of demonstration program results will identify potential mission improvement considerations that will help ensure successful mission completion. This paper will discuss the history, progress, and future activities that will define and mitigate the mission risk.