Science.gov

Sample records for disposed sealed radioactive

  1. Radioactive waste disposal package

    DOEpatents

    Lampe, Robert F.

    1986-11-04

    A radioactive waste disposal package comprising a canister for containing vitrified radioactive waste material and a sealed outer shell encapsulating the canister. A solid block of filler material is supported in said shell and convertible into a liquid state for flow into the space between the canister and outer shell and subsequently hardened to form a solid, impervious layer occupying such space.

  2. Radioactive waste disposal package

    DOEpatents

    Lampe, Robert F.

    1986-01-01

    A radioactive waste disposal package comprising a canister for containing vitrified radioactive waste material and a sealed outer shell encapsulating the canister. A solid block of filler material is supported in said shell and convertible into a liquid state for flow into the space between the canister and outer shell and subsequently hardened to form a solid, impervious layer occupying such space.

  3. Long-Term Safe Storage and Disposal of Spent Sealed Radioactive Sources in Borehole Type Repositories

    SciTech Connect

    Ojovan, M. I.; Dmitriev, S. A.; Sobolev, I. A.

    2003-02-26

    Russian Federation has the leading experience in applying borehole storage/disposal method for SRS. A new immobilization technology for sources being disposed of in underground repositories was mastered by 1986 and since then it is used in the country. This method uses all advantages of borehole type repositories supplementing them with metal encapsulation of sources. Sources being uniformly allocated in the volume of underground vessel are fixed in the metal block hence ensuring long-term safety. The dissipation of radiogenic heat from SRS is considerably improved, radiation fields are reduced, and direct contact of sources to an environment is completely eliminated. The capacity of a typical borehole storage/disposal facility is increased almost 6 times applying metal immobilization. That has made new technology extremely favourable economically. The metal immobilization of SRS is considered as an option in Belarus and Ukraine as well as Bulgaria. Immobilization of sources in metal matrices can be a real solution for retrieval of SRS from inadequate repositories.

  4. Special Analysis for the Disposal of the Neutron Products Incorporated Sealed Source Waste Stream at the Area 5 Radioactive Waste Management Site, Nevada National Security Site, Nye County, Nevada

    SciTech Connect

    Shott, Gregory

    2014-08-31

    The purpose of this special analysis (SA) is to determine if the Neutron Products Incorporated (NPI) Sealed Sources waste stream (DRTK000000056, Revision 0) is suitable for disposal by shallow land burial (SLB) at the Area 5 Radioactive Waste Management Site (RWMS). The NPI Sealed Sources waste stream consists of 850 60Co sealed sources (Duratek [DRTK] 2013). The NPI Sealed Sources waste stream requires a special analysis (SA) because the waste stream 60Co activity concentration exceeds the Nevada National Security Site (NNSS) Waste Acceptance Criteria (WAC) Action Levels.

  5. Radioactive mixed waste disposal

    SciTech Connect

    Jasen, W.G.; Erpenbeck, E.G.

    1993-02-01

    Various types of waste have been generated during the 50-year history of the Hanford Site. Regulatory changes in the last 20 years have provided the emphasis for better management of these wastes. Interpretations of the Atomic Energy Act of 1954 (AEA), the Resource Conservation and Recovery Act of 1976 (RCRA), and the Hazardous and Solid Waste Amendments (HSWA) have led to the definition of radioactive mixed wastes (RMW). The radioactive and hazardous properties of these wastes have resulted in the initiation of special projects for the management of these wastes. Other solid wastes at the Hanford Site include low-level wastes, transuranic (TRU), and nonradioactive hazardous wastes. This paper describes a system for the treatment, storage, and disposal (TSD) of solid radioactive waste.

  6. Radioactive waste material disposal

    DOEpatents

    Forsberg, Charles W.; Beahm, Edward C.; Parker, George W.

    1995-01-01

    The invention is a process for direct conversion of solid radioactive waste, particularly spent nuclear fuel and its cladding, if any, into a solidified waste glass. A sacrificial metal oxide, dissolved in a glass bath, is used to oxidize elemental metal and any carbon values present in the waste as they are fed to the bath. Two different modes of operation are possible, depending on the sacrificial metal oxide employed. In the first mode, a regenerable sacrificial oxide, e.g., PbO, is employed, while the second mode features use of disposable oxides such as ferric oxide.

  7. Radioactive waste material disposal

    DOEpatents

    Forsberg, C.W.; Beahm, E.C.; Parker, G.W.

    1995-10-24

    The invention is a process for direct conversion of solid radioactive waste, particularly spent nuclear fuel and its cladding, if any, into a solidified waste glass. A sacrificial metal oxide, dissolved in a glass bath, is used to oxidize elemental metal and any carbon values present in the waste as they are fed to the bath. Two different modes of operation are possible, depending on the sacrificial metal oxide employed. In the first mode, a regenerable sacrificial oxide, e.g., PbO, is employed, while the second mode features use of disposable oxides such as ferric oxide. 3 figs.

  8. Final disposal of radioactive waste

    NASA Astrophysics Data System (ADS)

    Freiesleben, H.

    2013-06-01

    In this paper the origin and properties of radioactive waste as well as its classification scheme (low-level waste - LLW, intermediate-level waste - ILW, high-level waste - HLW) are presented. The various options for conditioning of waste of different levels of radioactivity are reviewed. The composition, radiotoxicity and reprocessing of spent fuel and their effect on storage and options for final disposal are discussed. The current situation of final waste disposal in a selected number of countries is mentioned. Also, the role of the International Atomic Energy Agency with regard to the development and monitoring of international safety standards for both spent nuclear fuel and radioactive waste management is described.

  9. Disposal of disused sealed radiation sources in Boreholes

    SciTech Connect

    Vicente, R.

    2007-07-01

    This paper gives a description of the concept of a geological repository for disposal of disused sealed radiation sources (DSRS) under development in the Institute of Energy and Nuclear Research (IPEN), in Brazil. DSRS represent a significant fraction of total activity of radioactive wastes to be managed. Most DSRS are collected and temporarily stored at IPEN. As of 2006, the total collected activity is 800 TBq in 7,508 industrial gauge or radiotherapy sources, 7.2 TBq in about 72,000 Americium-241 sources detached from lightning rods, and about 0,5 GBq in 20,857 sources from smoke detectors. The estimated inventory of sealed sources in the country is 2.7 hundred thousand sources with 26 PBq. The proposed repository is designed to receive the total inventory of sealed sources. A description of the pre-disposal facilities at IPEN is also presented. (authors)

  10. 10 CFR 835.1201 - Sealed radioactive source control.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 4 2013-01-01 2013-01-01 false Sealed radioactive source control. 835.1201 Section 835.1201 Energy DEPARTMENT OF ENERGY OCCUPATIONAL RADIATION PROTECTION Sealed Radioactive Source Control § 835.1201 Sealed radioactive source control. Sealed radioactive sources shall be used, handled,...

  11. 10 CFR 835.1201 - Sealed radioactive source control.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 4 2014-01-01 2014-01-01 false Sealed radioactive source control. 835.1201 Section 835.1201 Energy DEPARTMENT OF ENERGY OCCUPATIONAL RADIATION PROTECTION Sealed Radioactive Source Control § 835.1201 Sealed radioactive source control. Sealed radioactive sources shall be used, handled,...

  12. 10 CFR 835.1201 - Sealed radioactive source control.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 false Sealed radioactive source control. 835.1201 Section 835.1201 Energy DEPARTMENT OF ENERGY OCCUPATIONAL RADIATION PROTECTION Sealed Radioactive Source Control § 835.1201 Sealed radioactive source control. Sealed radioactive sources shall be used, handled,...

  13. 10 CFR 835.1202 - Accountable sealed radioactive sources.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 4 2014-01-01 2014-01-01 false Accountable sealed radioactive sources. 835.1202 Section 835.1202 Energy DEPARTMENT OF ENERGY OCCUPATIONAL RADIATION PROTECTION Sealed Radioactive Source Control § 835.1202 Accountable sealed radioactive sources. (a) Each accountable sealed radioactive...

  14. 10 CFR 835.1202 - Accountable sealed radioactive sources.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Accountable sealed radioactive sources. 835.1202 Section 835.1202 Energy DEPARTMENT OF ENERGY OCCUPATIONAL RADIATION PROTECTION Sealed Radioactive Source Control § 835.1202 Accountable sealed radioactive sources. (a) Each accountable sealed radioactive...

  15. 10 CFR 835.1202 - Accountable sealed radioactive sources.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 4 2012-01-01 2012-01-01 false Accountable sealed radioactive sources. 835.1202 Section 835.1202 Energy DEPARTMENT OF ENERGY OCCUPATIONAL RADIATION PROTECTION Sealed Radioactive Source Control § 835.1202 Accountable sealed radioactive sources. (a) Each accountable sealed radioactive...

  16. 10 CFR 835.1202 - Accountable sealed radioactive sources.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 false Accountable sealed radioactive sources. 835.1202 Section 835.1202 Energy DEPARTMENT OF ENERGY OCCUPATIONAL RADIATION PROTECTION Sealed Radioactive Source Control § 835.1202 Accountable sealed radioactive sources. (a) Each accountable sealed radioactive...

  17. 10 CFR 835.1201 - Sealed radioactive source control.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Sealed radioactive source control. 835.1201 Section 835.1201 Energy DEPARTMENT OF ENERGY OCCUPATIONAL RADIATION PROTECTION Sealed Radioactive Source Control § 835.1201 Sealed radioactive source control. Sealed radioactive sources shall be used, handled,...

  18. 10 CFR 835.1201 - Sealed radioactive source control.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 4 2012-01-01 2012-01-01 false Sealed radioactive source control. 835.1201 Section 835.1201 Energy DEPARTMENT OF ENERGY OCCUPATIONAL RADIATION PROTECTION Sealed Radioactive Source Control § 835.1201 Sealed radioactive source control. Sealed radioactive sources shall be used, handled,...

  19. 10 CFR 835.1202 - Accountable sealed radioactive sources.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 4 2013-01-01 2013-01-01 false Accountable sealed radioactive sources. 835.1202 Section 835.1202 Energy DEPARTMENT OF ENERGY OCCUPATIONAL RADIATION PROTECTION Sealed Radioactive Source Control § 835.1202 Accountable sealed radioactive sources. (a) Each accountable sealed radioactive...

  20. Radiation Safety of Sealed Radioactive Sources

    SciTech Connect

    Pryor, Kathryn H.

    2015-01-29

    Sealed radioactive sources are used in a wide variety of occupational settings and under differing regulatory/licensing structures. The definition of a sealed radioactive source varies between US regulatory authorities and standard-setting organizations. Potential problems with sealed sources cover a range of risks and impacts. The loss of control of high activity sealed sources can result in very high or even fatal doses to members of the public who come in contact with them. Sources that are not adequately sealed, and that fail, can cause spread of contamination and potential intake of radioactive material. There is also the possibility that sealed sources may be (or threatened to be) used for terrorist purposes and disruptive opportunities. Until fairly recently, generally-licensed sealed sources and devices received little, if any, regulatory oversight, and were often forgotten, lost or unaccounted for. Nonetheless, generally licensed devices can contain fairly significant quantities of radioactive material and there is some potential for exposure if a device is treated in a way that it was never designed. Industrial radiographers use and handle high activity and/or high-dose rate sealed sources in the field with a high degree of independence and minimal regulatory oversight. Failure to follow operational procedures and properly handle radiography sources can and has resulted in serious injuries and death. Industrial radiographers have experienced a disproportionately large fraction of incidents that result in unintended exposure to radiation. Sources do not have to contain significant quantities of radioactive material to cause problems in the event of their failure. A loss of integrity can cause the spread of contamination and potential exposure to workers and members of the public. The NCRP has previously provided recommendations on select aspects of sealed source programs. Future efforts to provide recommendations for sealed source programs are discussed.

  1. Current Situation for Management of Disused Sealed Radioactive Sources in Japan - 13025

    SciTech Connect

    Kusama, Keiji; Miyamoto, Yoichi

    2013-07-01

    As for the Sealed Radioactive Source currently used in Japan, many of them are imported from overseas. The U.S., Canada, Germany, the Netherlands, Belgium and Czech Republic are the main exporting States. Many of disused sealed radioactive sources are being returned to exporting States. The sealed radioactive sources which cannot be returned to exporting States are appropriately kept in the domestic storage facility. So, there are not main problem on the long term management of disused sealed radioactive sources in Japan. However, there are some difficulties on repatriate. One is reservation of a means of transport. The sea mail which conveys radioactive sources owing to reduction of movement of international cargo is decreasing in number. And there is a denial of shipment. Other one is that the manufacturer has already resigned from the work and cannot return disused sealed radioactive sources, or a manufacturer cannot specify and disused sources cannot be returned. The disused sealed radioactive source which cannot be repatriated is a little in term of radioactivity. As for the establishment of national measure of final disposal facility for disused sealed radioactive sources, in Japan, it is not yet installed with difficulty. Since there are many countries for which installation of a final disposal facility for disused sealed radioactive sources is difficult, the source manufacture country should respond positively to return the source which was manufactured and sold in the past. (authors)

  2. End of Life Decisions for Sealed Radioactive Sources.

    PubMed

    Pryor, Kathryn H

    2016-02-01

    Sealed radioactive sources are encountered in a wide variety of settings-from household smoke detectors and instrument check sources through fixed industrial gauges, industrial radiography, and well logging sources, to irradiators and medical teletherapy devices. In general, the higher the level of activity in the sealed source, the stricter the regulatory control that is applied to its use, control, and ultimate disposition. Lower levels of attention and oversight can and do lead to sources ending up in the wrong place--as orphan sources in uncontrolled storage, disposed in a sanitary landfill, melted down in metal recycling operations and incorporated into consumer products, or handled by an unsuspecting member of the public. There is a range of issues that contribute to the problem of improper disposal of sealed sources and, in particular, to disused source disposal. Generally licensed sources and devices are particularly at risk of being disposed incorrectly. Higher activity generally licensed sources, although required to be registered with the (NRC) or an Agreement State, receive limited regulatory oversight and are not tracked on a national scale. Users frequently do not consider the full life-cycle costs when procuring sources or devices and discover that they cannot afford and/or are unwilling to pay the associated costs to package, transport and dispose of their sources properly. The NRC requirements for decommissioning funding plans and financial assurance are not adequate to cover sealed source transport and disposal costs fully. While there are regulatory limits for storage of disused sources, enforcement is limited, and there are only limited financial incentives in a small number of states for owners to dispose of the sources. In some cases, the lack of availability of approved Type B shipping casks presents an additional barrier to sealed source disposal. The report of the Disused Sources Working Group does an excellent job of framing these issues

  3. The impact of NRC guidance on concentration averaging on low level waste sealed source disposal - 11424

    SciTech Connect

    Whitworth, Julia; Stewart, Bill; Cuthbertson, Abigail

    2011-01-20

    As part of its ongoing efforts to revise the Nuclear Regulatory Commission's (NRC) current position on blending to be risk-informed and performance based and its current review of the low-level waste classification codified in 10 CFR 61.55, the Nuclear Regulatory Commission (NRC) has stated that it may review the 1995 'Branch Technical Position on Concentration Averaging and Encapsulation' (BTP), which is still commonly used today. Such a review will have timely advantages, given the lack of commercial disposal availability within the United States for radioactive sealed sources that are in wide beneficial use across the country. The current application of the BTP guidance has resulted in an effective cap on commercial disposal for sources larger than 1.1 TBq (30 Ci). This paper will analyze how the BTP has been implemented with respect to sealed sources, what the implications have been for commercial disposal availability, and whether alternative packaging configurations could be considered for disposal.

  4. The safe disposal of radioactive wastes

    PubMed Central

    Kenny, A. W.

    1956-01-01

    A comprehensive review is given of the principles and problems involved in the safe disposal of radioactive wastes. The first part is devoted to a study of the basic facts of radioactivity and of nuclear fission, the characteristics of radioisotopes, the effects of ionizing radiations, and the maximum permissible levels of radioactivity for workers and for the general public. In the second part, the author describes the different types of radioactive waste—reactor wastes and wastes arising from the use of radioisotopes in hospitals and in industry—and discusses the application of the maximum permissible levels of radioactivity to their disposal and treatment, illustrating his discussion with an account of the methods practised at the principal atomic energy establishments. PMID:13374534

  5. Offsite source recovery project - ten years of sealed source recovery and disposal

    SciTech Connect

    Whitworth, Julia Rose; Pearson, Mike; Witkowski, Ioana; Wald - Hopkins, Mark; Cuthbertson, A

    2010-01-01

    The Global Threat Reduction Initiative's (GTRI) Offsite Source Recovery Project (OSRP) has been recovering excess and unwanted radioactive sealed sources for ten years. In January 2009, GTRI announced that the project had recovered 20,000 sealed radioactive sources (this number has since increased to more than 23,000). This project grew out of early efforts at Los Alamos National Laboratory (LANL) to recover and disposition excess Plutonium-239 (Pu-239) sealed sources that were distributed in the 1960s and 1970s under the Atoms for Peace Program. Decades later, these sources began to exceed their special form certifications or fall out of regular use. As OSRP has collected and stored sealed sources, initially using 'No Path Forward' waste exemptions for storage within the Department of Energy (DOE) complex, it has consistently worked to create disposal pathways for the material it has recovered. The project was initially restricted to recovering sealed sources that would meet the definition of Greater-than-Class-C (GTCC) low-level radioactive waste, assisting DOE in meeting its obligations under the Low-level Radioactive Waste Policy Act Amendments (PL 99-240) to provide disposal for this type of waste. After being transferred from DOE-Environmental Management (EM) to the U.S. National Nuclear Security Administration (NNSA) to be part of GTRI, OSRP's mission was expanded to include not only material that would be classified as GTCC when it became waste, but also any other materials that might constitute a 'national security consideration.' It was recognized at the time that the GTCC category was a waste designation having to do with environmental consequence, rather than the threat posed by deliberate or accidental misuse. The project faces barriers to recovery in many areas, but disposal continues to be one of the more difficult to overcome. This paper discusses OSRP's disposal efforts over its 10-year history. For sources meeting the DOE definition of

  6. Management of Disused Radioactive Sealed Sources in Egypt - 13512

    SciTech Connect

    Mohamed, Y.T.; Hasan, M.A.; Lasheen, Y.F.

    2013-07-01

    The future safe development of nuclear energy and progressive increasing use of sealed sources in medicine, research, industry and other fields in Egypt depends on the safe and secure management of disused radioactive sealed sources. In the past years have determined the necessity to formulate and apply the integrated management program for radioactive sealed sources to assure harmless and ecological rational management of disused sealed sources in Egypt. The waste management system in Egypt comprises operational and regulatory capabilities. Both of these activities are performed under legislations. The Hot Laboratories and Waste Management Center HLWMC, is considered as a centralized radioactive waste management facility in Egypt by law 7/2010. (authors)

  7. Radioactivity in the industrial effluent disposed soil

    NASA Astrophysics Data System (ADS)

    Senthilkumar, R. D.; Narayanaswamy, R.; Meenashisundaram, V.

    2012-04-01

    Studies on radiation and radioactivity distribution in the soils of effluent disposed from the sugar industry in India have been conducted. The external gamma dose rates in air and natural radionuclides activities in the soils were measured using an Environmental Radiation Dosimeter and a Gamma-ray Spectrometer respectively. The soil samples were also subject to various physico-chemical analyses. This study revealed some remarkable results that are discussed in the article.

  8. Geochemical aspects of radioactive waste disposal

    SciTech Connect

    Brookins, D.G.

    1984-01-01

    The book addresses various topics related to the geochemistry of waste disposal: natural radioactivity, kinds of radioactive waste, details of possible disposal sites, low-level waste, uranium mill tailing, natural analogs, waste forms, and engineered barriers. Emphasis throughout is on the importance of natural analogs, the behavior of elements resembling those to be put in a waste repository as they occur in natural situations where the temperature, pressure, and movement of ground water are similar to those expected near a repository. The author is convinced that conclusions drawn from the study of analog elements are directly applicable to predictions about radionuclide behavior, and that the observed near-immobility of most of these elements in comparable geologic environments is good evidence that radioactive waste can be disposed of underground with negligible effects on the biosphere. Much of his own research has been in this area, and the best parts of the book are the descriptions of his work on trace elements in the salt minerals at the Waste Isolation Pilot Plant in southeastern New Mexico, on the movement of radionuclides and their daughter elements from the famous Precambrian reactor at Oklahoma in Gabon, and on the distribution of analog elements in rocks near the contacts of igneous intrusions.

  9. 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).

  10. Operational Strategies for Low-Level Radioactive Waste Disposal Site in Egypt - 13513

    SciTech Connect

    Mohamed, Yasser T.

    2013-07-01

    The ultimate aims of treatment and conditioning is to prepare waste for disposal by ensuring that the waste will meet the waste acceptance criteria of a disposal facility. Hence the purpose of low-level waste disposal is to isolate the waste from both people and the environment. The radioactive particles in low-level waste emit the same types of radiation that everyone receives from nature. Most low-level waste fades away to natural background levels of radioactivity in months or years. Virtually all of it diminishes to natural levels in less than 300 years. In Egypt, The Hot Laboratories and Waste Management Center has been established since 1983, as a waste management facility for LLW and ILW and the disposal site licensed for preoperational in 2005. The site accepts the low level waste generated on site and off site and unwanted radioactive sealed sources with half-life less than 30 years for disposal and all types of sources for interim storage prior to the final disposal. Operational requirements at the low-level (LLRW) disposal site are listed in the National Center for Nuclear Safety and Radiation Control NCNSRC guidelines. Additional procedures are listed in the Low-Level Radioactive Waste Disposal Facility Standards Manual. The following describes the current operations at the LLRW disposal site. (authors)

  11. Safety and security management of disused sealed radioactive sources in Thailand

    NASA Astrophysics Data System (ADS)

    Ya-anant, N.; Nuanjan, P.; Phattanasub, A.; Akharawutchayanon, T.; O-manee, A.; Prasertchiewchan, N.; Benitez-Navarro, J. C.

    2015-05-01

    When sealed radioactive sources are no longer in use, they should be returned back to the country of origin. However, most of them could not be returned to the origin; therefore, disused sealed radioactive sources (DSRS) have to be managed locally to ensure the safety and the security for long term storage before final disposal. The Radioactive Waste Management Center, Thailand Institute of Nuclear Technology, is authorized to operate the treatment, conditioning and storage of DSRS in Thailand. This paper will describe the operational procedures on characterization technique, identifation of unknown sources, volume reduction technique, re-packaging, registration and record keeping of DSRS. The successful results included that the record keeping of DSRS has been developed, and the national inventory of stored DSRS has been made up to date. The results confirmed that the quality control at the DSRS storage facility at Thailand Institute of Nuclear Technology was established and well implemented to ensure safe and secure management.

  12. Greater confinement disposal of radioactive wastes

    SciTech Connect

    Trevorrow, L.E.; Gilbert, T.L.; Luner, C.; Merry-Libby, P.A.; Meshkov, N.K.; Yu, C.

    1985-01-01

    Low-level radioactive waste (LLW) includes a broad spectrum of different radionuclide concentrations, half-lives, and hazards. Standard shallow-land burial practice can provide adequate protection of public health and safety for most LLW. A small volume fraction (approx. 1%) containing most of the activity inventory (approx. 90%) requires specific measures known as greater-confinement disposal (GCD). Different site characteristics and different waste characteristics - such as high radionuclide concentrations, long radionuclide half-lives, high radionuclide mobility, and physical or chemical characteristics that present exceptional hazards - lead to different GCD facility design requirements. Facility design alternatives considered for GCD include the augered shaft, deep trench, engineered structure, hydrofracture, improved waste form, and high-integrity container. Selection of an appropriate design must also consider the interplay between basic risk limits for protection of public health and safety, performance characteristics and objectives, costs, waste-acceptance criteria, waste characteristics, and site characteristics.

  13. Performance of cement-based seal-system components in a waste-disposal environment

    SciTech Connect

    Malone, P.G.; Wakeley, L.D.; Burkes, J.P.; McDaniel, E.W.

    1994-12-31

    A grout based on portland cement, Class F fly ash, and bentonite clay was developed as part of the closure system of shallow subsurface structures for disposal of low-activity radioactive wastes. Heat output, volume change, and compressive strength of the sealing grout were monitored with time, at elevated temperature, and in physical models, to determine if this closure grout could maintain adequate volume stability and other required physical properties in the internal environment of the disposal structure. To determine if contact with an alkaline liquid waste would cause chemical deterioration of the sealing grout, cured specimens were immersed in a liquid waste simulant containing high concentrations of sodium and aluminum salts. After 21 days at 60 C, specimens increased in mass without significant changes in volume. XRD revealed crystallization of sodium aluminum silicate hydrate. The new phase has an XRD pattern similar to the commercial synthetic zeolite Losod. Scanning electron microscopy used with x-ray fluorescence showed that clusters of this phase had formed in grout pores, to increase rout density and decrease its effective porosity. Testing was repeated at 100 C for 5 days using a simulant containing sodium hydroxide and aluminum nitrate and results were similar. Physical and chemical tests indicate acceptable performance of this grout as a seal-system component.

  14. High-Level Radioactive Waste: Safe Storage and Ultimate Disposal.

    ERIC Educational Resources Information Center

    Dukert, Joseph M.

    Described are problems and techniques for safe disposal of radioactive waste. Degrees of radioactivity, temporary storage, and long-term permanent storage are discussed. Included are diagrams of estimated waste volumes to the year 2000 and of an artist's conception of a permanent underground disposal facility. (SL)

  15. The political science of radioactive waste disposal

    SciTech Connect

    Jacobi, L.R. Jr.

    1996-06-01

    This paper was first presented at the annual meeting of the HPS in New Orleans in 1984. Twelve years later, the basic lessons learned are still found to be valid. In 1984, the following things were found to be true: A government agency is preferred by the public over a private company to manage radioactive waste. Semantics are important--How you say it is important, but how it is heard is more important. Public information and public relations are very important, but they are the last thing of concern to a scientist. Political constituency is important. Don`t overlook the need for someone to be on your side. Don`t forget that the media is part of the political process-they can make you or break you. Peer technical review is important, but so is citizen review. Sociology is an important issue that scientists and technical people often overlook. In summary, despite the political nature of radioactive waste disposal, it is as true today as it was in 1984 that technical facts must be used to reach sound technical conclusions. Only then, separately and openly, should political factors be considered. So, what can be said today that wasn`t said in 1984? Nothing. {open_quotes}It`s deja vu all over again.{close_quotes}

  16. Conditioning and Repackaging of Spent Radioactive Cs-137 and Co-60 Sealed Sources in Egypt - 13490

    SciTech Connect

    Hasan, M.A.; Selim, Y.T.; El-Zakla, T.

    2013-07-01

    Radioactive Sealed sources (RSSs) are widely use all over the world in medicine, agriculture, industry, research, etc. The accidental misuse and exposure to RSSs has caused significant environmental contamination, serious injuries and many deaths. The high specific activity of the materials in many RSSs means that the spread of as little as microgram quantities can generate significant risk to human health and inhibit the use of buildings and land. Conditioning of such sources is a must to protect humans and environment from the hazard of ionizing radiation and contamination. Conditioning is also increase the security of these sources by decreasing the probability of stolen and/or use in terrorist attacks. According to the law No.7/2010, Egyptian atomic energy authority represented in the hot laboratories and waste management center (centralized waste facility, HLWMC) has the responsibility of collecting, conditioning, storing and management of all types of radioactive waste from all Egyptian territory including spent radioactive sealed sources (SRSSs). This paper explains the conditioning procedures for two of the most common SRSSs, Cs{sup 137} and Co{sup 60} sources which make up more than 90% of the total spent radioactive sealed sources stored in our centralized waste facility as one of the major activities of hot laboratories and waste management center. Conditioning has to meet three main objectives, be acceptable for storage, enable their safe transport, and comply with disposal requirements. (authors)

  17. Ceramic Borehole Seals for Nuclear Waste Disposal Applications

    NASA Astrophysics Data System (ADS)

    Lowry, B.; Coates, K.; Wohletz, K.; Dunn, S.; Patera, E.; Duguid, A.; Arnold, B.; Zyvoloski, G.; Groven, L.; Kuramyssova, K.

    2015-12-01

    Sealing plugs are critical features of the deep borehole system design. They serve as structural platforms to bear the weight of the backfill column, and as seals through their low fluid permeability and bond to the borehole or casing wall. High hydrostatic and lithostatic pressures, high mineral content water, and elevated temperature due to the waste packages and geothermal gradient challenge the long term performance of seal materials. Deep borehole nuclear waste disposal faces the added requirement of assuring performance for thousands of years in large boreholes, requiring very long term chemical and physical stability. A high performance plug system is being developed which capitalizes on the energy of solid phase reactions to form a ceramic plug in-situ. Thermites are a family of self-oxidized metal/oxide reactions with very high energy content and the ability to react under water. When combined with engineered additives the product exhibits attractive structural, sealing, and corrosion properties. In the initial phase of this research, exploratory and scaled tests demonstrated formulations that achieved controlled, fine grained, homogeneous, net shape plugs composed predominantly of ceramic material. Laboratory experiments produced plug cores with confined fluid permeability as low as 100 mDarcy, compressive strength as high as 70 MPa (three times the strength of conventional well cement), with the inherent corrosion resistance and service temperature of ceramic matrices. Numerical thermal and thermal/structural analyses predicted the in-situ thermal performance of the reacted plugs, showing that they cooled to ambient temperature (and design strength) within 24 to 48 hours. The current development effort is refining the reactant formulations to achieve desired performance characteristics, developing the system design and emplacement processes to be compatible with conventional well service practices, and understanding the thermal, fluid, and structural

  18. Reference design and operations for deep borehole disposal of high-level radioactive waste.

    SciTech Connect

    Herrick, Courtney Grant; Brady, Patrick Vane; Pye, Steven; Arnold, Bill Walter; Finger, John Travis; Bauer, Stephen J.

    2011-10-01

    A reference design and operational procedures for the disposal of high-level radioactive waste in deep boreholes have been developed and documented. The design and operations are feasible with currently available technology and meet existing safety and anticipated regulatory requirements. Objectives of the reference design include providing a baseline for more detailed technical analyses of system performance and serving as a basis for comparing design alternatives. Numerous factors suggest that deep borehole disposal of high-level radioactive waste is inherently safe. Several lines of evidence indicate that groundwater at depths of several kilometers in continental crystalline basement rocks has long residence times and low velocity. High salinity fluids have limited potential for vertical flow because of density stratification and prevent colloidal transport of radionuclides. Geochemically reducing conditions in the deep subsurface limit the solubility and enhance the retardation of key radionuclides. A non-technical advantage that the deep borehole concept may offer over a repository concept is that of facilitating incremental construction and loading at multiple perhaps regional locations. The disposal borehole would be drilled to a depth of 5,000 m using a telescoping design and would be logged and tested prior to waste emplacement. Waste canisters would be constructed of carbon steel, sealed by welds, and connected into canister strings with high-strength connections. Waste canister strings of about 200 m length would be emplaced in the lower 2,000 m of the fully cased borehole and be separated by bridge and cement plugs. Sealing of the upper part of the borehole would be done with a series of compacted bentonite seals, cement plugs, cement seals, cement plus crushed rock backfill, and bridge plugs. Elements of the reference design meet technical requirements defined in the study. Testing and operational safety assurance requirements are also defined. Overall

  19. Integrated Management Program Radioactive Sealed Sources in Egypt

    SciTech Connect

    Hasan, A.; Cochran, J. R.; El-Adham, K.; El-Sorougy, R.

    2003-02-26

    The radioactive materials in ''public'' locations are typically contained in small, stainless steel capsules known as sealed radiation sources (RS). These capsules seal in the radioactive materials, but not the radiation, because it is the radiation that is needed for a wide variety of applications at hospitals, medical clinics, manufacturing plants, universities, construction sites, and other facilities in the public sector. Radiation sources are readily available, and worldwide there are hundreds of thousands of RS. The IMPRSS Project is a cooperative development between the Egyptian Atomic Energy Authority (EAEA), Egyptian Ministry of Health (MOH), Sandia National Laboratories (SNL), New Mexico Tech University (NMT), and Agriculture Cooperative Development International (ACDI/VOCA). SNL will coordinate the work scope between the participant organizations.

  20. Commercial low-level radioactive waste disposal in the US

    SciTech Connect

    Smith, P.

    1995-10-01

    Why are 11 states attempting to develop new low-level radioactive waste disposal facilities? Why is only on disposal facility accepting waste nationally? What is the future of waste disposal? These questions are representative of those being asked throughout the country. This paper attempts to answer these questions in terms of where we are, how we got there, and where we might be going.

  1. Management and disposal of waste from sites contaminated by radioactivity

    NASA Astrophysics Data System (ADS)

    Roberts, Carlyle J.

    1998-06-01

    Various methods of managing and disposing of wastes generated by decontamination and decommissioning (D & D) activities are described. This review of current waste management practices includes a description of waste minimization and volume reduction techniques and their applicability to various categories of radwaste. The importance of the physical properties of the radiation and radioactivity in determining the methodology of choice throughout the D & D process is stressed. The subject is introduced by a survey of the common types of radioactive contamination that must be managed and the more important hazards associated with each type. Comparisons are made among high level, transuranic, low level, and radioactive mixed waste, and technologically-enhanced, naturally-occurring radioactive material (TENORM). The development of appropriate clean-up criteria for each category of contaminated waste is described with the aid of examples drawn from actual practice. This includes a discussion of the application of pathway analysis to the derivation of residual radioactive material guidelines. The choice between interim storage and permanent disposal of radioactive wastes is addressed. Approaches to permanent disposal of each category of radioactive waste are described and illustrated with examples of facilities that have been constructed or are planned for implementation in the near future. Actual experience at older, existing, low-level waste disposal facilities is discussed briefly.

  2. Disposal of radioactive iodine in space

    NASA Technical Reports Server (NTRS)

    Burns, R. E.; Defield, J. G.

    1978-01-01

    The possibility of space disposal of iodine waste from nuclear power reactors is investigated. The space transportation system utilized relies upon the space shuttle, a liquid hydrogen/liquid oxygen orbit transfer vehicle, and a solid propellant final stage. The iodine is assumed to be in the form of either an iodide or an iodate, and calculations assume that the final destination is either solar orbit or solar system escape. It is concluded that space disposal of iodine is feasible.

  3. Management of Disused Radioactive Sealed Sources in the Slovak Republic - 12100

    SciTech Connect

    Salzer, Peter

    2012-07-01

    After splitting-up the Czechoslovak Federation in 1993, the system of management of institutional radioactive waste, where disused sources represent its significant part, had had to build from beginning, since all corresponding activities had remained in the Czech part of the Federation. The paper presents the development of legislative and institutional framework of the disused radioactive sealed source management, development of the national inventory and development of management practices. According the Governmental decision (1994), the management of disused sealed sources and institutional radioactive waste at whole was based on maximal utilization of facilities inside nuclear facilities, particularly in the NPP A1 (shut down in the past, currently under decommissioning). This approach has been recently changing by Governmental decision (2009) to construct 'non-nuclear facility' - central storage for remained disused sealed sources collected from the places of use, where they were stored in some cases for tens of years. The approaches to siting and construction of this storage facility will be presented, as well as the current approaches to solution of the disused radioactive sources final disposal. Environmental impact assessment process in regard to the given facility/activity is slowly drawing to a close. The final statement of the Ministry of Environment can be expected in January or February 2012, probably recommending option 1 as preferred [6]. According to the Slovak legislation, the final statement has a status of recommendation for ongoing processes leading to the siting license. Very recently, in December 2012, Government of the Slovak republic decided to postpone putting the facility into operation by the end of June, 2014. (author)

  4. Lessons Learned from Radioactive Waste Storage and Disposal Facilities

    SciTech Connect

    Esh, David W.; Bradford, Anna H.

    2008-01-15

    The safety of radioactive waste disposal facilities and the decommissioning of complex sites may be predicated on the performance of engineered and natural barriers. For assessing the safety of a waste disposal facility or a decommissioned site, a performance assessment or similar analysis is often completed. The analysis is typically based on a site conceptual model that is developed from site characterization information, observations, and, in many cases, expert judgment. Because waste disposal facilities are sited, constructed, monitored, and maintained, a fair amount of data has been generated at a variety of sites in a variety of natural systems. This paper provides select examples of lessons learned from the observations developed from the monitoring of various radioactive waste facilities (storage and disposal), and discusses the implications for modeling of future waste disposal facilities that are yet to be constructed or for the development of dose assessments for the release of decommissioning sites. Monitoring has been and continues to be performed at a variety of different facilities for the disposal of radioactive waste. These include facilities for the disposal of commercial low-level waste (LLW), reprocessing wastes, and uranium mill tailings. Many of the lessons learned and problems encountered provide a unique opportunity to improve future designs of waste disposal facilities, to improve dose modeling for decommissioning sites, and to be proactive in identifying future problems. Typically, an initial conceptual model was developed and the siting and design of the disposal facility was based on the conceptual model. After facility construction and operation, monitoring data was collected and evaluated. In many cases the monitoring data did not comport with the original site conceptual model, leading to additional investigation and changes to the site conceptual model and modifications to the design of the facility. The following cases are discussed

  5. Disposal of liquid radioactive wastes through wells or shafts

    SciTech Connect

    Perkins, B.L.

    1982-01-01

    This report describes disposal of liquids and, in some cases, suitable solids and/or entrapped gases, through: (1) well injection into deep permeable strata, bounded by impermeable layers; (2) grout injection into an impermeable host rock, forming fractures in which the waste solidifies; and (3) slurrying into excavated subsurface cavities. Radioactive materials are presently being disposed of worldwide using all three techniques. However, it would appear that if the techniques were verified as posing minimum hazards to the environment and suitable site-specific host rock were identified, these disposal techniques could be more widely used.

  6. Disposal of liquid radioactive wastes through wells or shafts

    NASA Astrophysics Data System (ADS)

    Perkins, B. L.

    1982-01-01

    Liquids and, in some cases, suitable solids and/or entrapped gases can be disposed of by: (1) well injection into deep permeable strata, bounded by impermeable layers; (2) grout injection into an impermeable host rock, forming fractures in which the waste solidifies; and (3) slurrying into excavated subsurface cavities. Radioactive materials are presently being disposed of worldwide using all three techniques; however, it would appear that if the techniques were verified as posing minimum hazards to the environment and suitable site-specific host rock were identified, these disposal techniques could be more widely used.

  7. RADIOACTIVE MATERIAL SHIPPING PACKAGINGS AND METAL TO METAL SEALS FOUND IN THE CLOSURES OF CONTAINMENT VESSELS INCORPORATING CONE SEAL CLOSURES

    SciTech Connect

    Loftin, B; Glenn Abramczyk, G; Allen Smith, A

    2007-06-06

    The containment vessels for the Model 9975 radioactive material shipping packaging employ a cone-seal closure. The possibility of a metal-to-metal seal forming between the mating conical surfaces, independent of the elastomer seals, has been raised. It was postulated that such an occurrence would compromise the containment vessel hydrostatic and leakage tests. The possibility of formation of such a seal has been investigated by testing and by structural and statistical analyses. The results of the testing and the statistical analysis demonstrate and procedural changes ensure that hydrostatic proof and annual leakage testing can be accomplished to the appropriate standards.

  8. Compilation of current literature on seals, closures, and leakage for radioactive material packagings

    SciTech Connect

    Warrant, M.M.; Ottinger, C.A.

    1989-01-01

    This report presents an overview of the features that affect the sealing capability of radioactive material packagings currently certified by the US Nuclear Regulatory Commission. The report is based on a review of current literature on seals, closures, and leakage for radioactive material packagings. Federal regulations that relate to the sealing capability of radioactive material packagings, as well as basic equations for leakage calculations and some of the available leakage test procedures are presented. The factors which affect the sealing capability of a closure, including the properties of the sealing surfaces, the gasket material, the closure method and the contents are discussed in qualitative terms. Information on the general properties of both elastomer and metal gasket materials and some specific designs are presented. A summary of the seal material, closure method, and leakage tests for currently certified packagings with large diameter seals is provided. 18 figs., 9 tabs.

  9. Radioactive waste disposal in simulated peat bog repositories

    SciTech Connect

    Schell, W.R.; Massey, C.D.

    1987-01-01

    The Low Level Radioactive Waste Policy Act of 1980 and the Low Level Radioactive Waste Policy Amendments Act of 1985 have required state governments to be responsible for providing low-level waste (LLW) disposal facilities in their respective areas. Questions are (a) is the technology sufficiently advanced to ensure that radioactive wastes can be stored for 300 to 1000 yr without entering into any uncontrolled area. (b) since actual experience does not exist for nuclear waste disposal over this time period, can the mathematical models developed be tested and verified using unequivocal data. (c) how can the public perception of the problem be addressed and the potential risk assessment of the hazards be communicated. To address the technical problems of nuclear waste disposal in the acid precipitation regions of the Northern Hemisphere, a project was initiated in 1984 to evaluate an alternative method of nuclear waste disposal that may not rely completely on engineered barriers to protect the public. Certain natural biogeochemical systems have been retaining deposited materials since the last Ice Age (12,000 to 15,000 yr). It is the authors belief that the biogeochemical system of wetlands and peat bogs may provide an example of an analogue for a nuclear waste repository system that can be tested and verified over a sufficient time period, at least for the LLW disposal problem.

  10. Radioactive waste disposal via electric propulsion

    NASA Technical Reports Server (NTRS)

    Burns, R. E.

    1975-01-01

    It is shown that space transportation is a feasible method of removal of radioactive wastes from the biosphere. The high decay heat of the isotopes powers a thermionic generator which provides electrical power for ion thrust engines. The massive shields (used to protect ground and flight personnel) are removed in orbit for subsequent reuse; the metallic fuel provides a shield for the avionics that guides the orbital stage to solar system escape. Performance calculations indicate that 4000 kg. of actinides may be removed per Shuttle flight. Subsidiary problems - such as cooling during ascent - are discussed.

  11. System for disposing of radioactive water

    DOEpatents

    Gotchy, Reginald L.

    1976-01-13

    A system for reducing radioactivity released to the biosphere in the course of producing natural gas from a reservoir stimulated by the detonation of nuclear explosives therein. Tritiated water produced with the gas is separated out and returned to a nuclear chimney through a string of tubing positioned within the well casing. The tubing string is positioned within the well casing in a manner which enhances separation of the water out of the gas and minimizes entrainment of water into the gas flowing out of the chimney.

  12. Natural Radioactivity in Monitoring Waste Disposals

    NASA Astrophysics Data System (ADS)

    de Meijer, R. J.; Limburg, J.; Venema, L. B.

    Monitoring large (underwater) surfaces, with strongly varying composition, requires a sampling density, exceeding the capabilities of standard techniques. These techniques involve sample collection and a number of treatments and measurements in laboratory; both steps are laborious, tedious and costly. This paper shows that a trailing detector system of natural γ-rays provides quantitative information on the dynamics at and around a waste disposal site. In this paper the technique is applied to monitor dumpsites of gold mines from an aircraft and the dispersal of dredge spoil from Rotterdam harbour dumped at the North Sea by vessel. The sea-floor monitoring has been conducted in detail, including the derivation of sediment composition and assessing by means of a mass-balance equation the transport directions and quantities in time.

  13. The UK's Surplus Source Disposal Programme: successful management of a national radioactive legacy.

    PubMed

    Williams, Clive; Burns, Philip; Wakerley, Malcolm; Watson, Isabelle; Cook, Marianne; Moloney, Barry

    2010-06-01

    Between 2004 and 2009, the Surplus Source Disposal Programme (SSDP) arranged and subsidised the safe disposal or recycling of more than 11,000 unwanted radioactive items containing in total more than 8.5 x 10(14) Bq of activity, from some 500 sites throughout the United Kingdom. Sources were removed principally from universities, schools and colleges, museums, and hospitals. SSDP was funded by the UK Government and managed by the Environment Agency. The programme was delivered at a total cost of pound sterling 7.14 million, nearly pound sterling 2 million less than its initial budget. This was a big success for health and safety, the environment, business and the public purse. Current legislative requirements under the High Activity Sealed Sources Directive, which came into effect during 2005, will prevent a build-up of high activity surplus sources in future. Continuing vigilance may be needed to avoid a build-up of lower activity disused sources. PMID:20530861

  14. Directions in low-level radioactive waste management: A brief history of commercial low-level radioactive waste disposal

    SciTech Connect

    Not Available

    1994-08-01

    This report presents a history of commercial low-level radioactive waste disposal in the United States, with emphasis on the history of six commercially operated low-level radioactive waste disposal facilities. The report includes a brief description of important steps that have been taken during the last decade to ensure the safe disposal of low-level radioactive waste in the 1990s and beyond. These steps include the issuance of comprehensive State and Federal regulations governing the disposal of low-level radioactive waste, and the enactment of Federal laws making States responsible for the disposal of such waste generated within their borders.

  15. Generation and release of radioactive gases in LLW disposal facilities

    SciTech Connect

    Yim, M.S.; Simonson, S.A.

    1995-02-01

    The atmospheric release of radioactive gases from a generic engineered LLW disposal facility and its radiological impacts were examined. To quantify the generation of radioactive gases, detailed characterization of source inventory for carbon-14, tritium, iodine-129, krypton-85, and radon-222, was performed in terms of their activity concentrations; their distribution within different waste classes, waste forms and containers; and their subsequent availability for release in volatile or gaseous form. The generation of gases was investigated for the processes of microbial activity, radiolysis, and corrosion of waste containers and metallic components in wastes. The release of radionuclides within these gases to the atmosphere was analyzed under the influence of atmospheric pressure changes.

  16. Disposal of low-level radioactive waste at the Savannah River Site

    SciTech Connect

    Sauls, V.W.

    1993-03-01

    An important objective of the Savannah River Site`s low-level radioactive waste management program is to isolate the waste from the environment both now and well into the future. A key element in achieving this is the disposal of low-level radioactive waste in sealed concrete vaults. Historically the Site has disposed of low-level radioactive waste via shallow land burial. In 1987, it was decided that better isolation from the environment was required. At that time several options for achieving this isolation were studied and below grade concrete vaults were chosen as the best method. This paper discusses the performance objectives for the vaults, the current design of the vaults and plans for the design of future vaults, the cost to construct the vaults, and the performance assessment on the vaults. Construction of the first set of vaults is essentially complete and readiness reviews before the start of waste receipt are being performed. Startup is to begin late in calendar year 1992 and continue through early CY 1993. The performance assessment is under way and the first draft is to be completed in early 1993.

  17. Low-level radioactive waste disposal facility closure

    SciTech Connect

    White, G.J.; Ferns, T.W.; Otis, M.D.; Marts, S.T.; DeHaan, M.S.; Schwaller, R.G.; White, G.J. )

    1990-11-01

    Part I of this report describes and evaluates potential impacts associated with changes in environmental conditions on a low-level radioactive waste disposal site over a long period of time. Ecological processes are discussed and baselines are established consistent with their potential for causing a significant impact to low-level radioactive waste facility. A variety of factors that might disrupt or act on long-term predictions are evaluated including biological, chemical, and physical phenomena of both natural and anthropogenic origin. These factors are then applied to six existing, yet very different, low-level radioactive waste sites. A summary and recommendations for future site characterization and monitoring activities is given for application to potential and existing sites. Part II of this report contains guidance on the design and implementation of a performance monitoring program for low-level radioactive waste disposal facilities. A monitoring programs is described that will assess whether engineered barriers surrounding the waste are effectively isolating the waste and will continue to isolate the waste by remaining structurally stable. Monitoring techniques and instruments are discussed relative to their ability to measure (a) parameters directly related to water movement though engineered barriers, (b) parameters directly related to the structural stability of engineered barriers, and (c) parameters that characterize external or internal conditions that may cause physical changes leading to enhanced water movement or compromises in stability. Data interpretation leading to decisions concerning facility closure is discussed. 120 refs., 12 figs., 17 tabs.

  18. Cement-based grouts in geological disposal of radioactive waste

    SciTech Connect

    Onofrei, M.

    1996-04-01

    The behavior and performance of a specially developed high-performance cement-based grout has been studied through a combined laboratory and in situ research program conducted under the auspices of the Canadian Nuclear Fuel Waste Management Program (CNFWMP). A new class of cement-based grouts - high-performance grouts-with the ability to penetrate and seal fine fractures was developed and investigated. These high-performance grouts, which were injected into fractures in the granitic rock at the Underground Research Laboratory (URL) in Canada, are shown to successfully reduce the hydraulic conductivity of the rock mass from <10{sup -7} m s{sup -1} to 10{sup -9} m s{sup -1} and to penetrate fissures in the rock with apertures as small as 10 {mu}m. Furthermore, the laboratory studies have shown that this high - performance grout has very low hydraulic conductivity and is highly leach resistant under repository conditions. Microcracks generated in this materials from shrinkage, overstressing or thermal loads are likely to self-seal. The results of these studies suggest that the high-performance grouts can be considered as viable materials in disposal-vault sealing applications. Further work is needed to fully justify extrapolation of the results of the laboratory studies to time scales relevant to performance assessment.

  19. Justification Of The Use Of Boreholes For Disposal Of Sealed Radiological Sources

    SciTech Connect

    Zarling, John; Johnson, Peter

    2008-01-01

    Soon there will be only 14 states in two compacts that are able to dispose of Low Level Waste (LLW): the Northwest and Rocky Mountain compact with disposal options in Richland, Washington, and the Atlantic compact with disposal options in Barnwell, South Carolina. How do states not in one of the two compacts dispose of their LLW? The Off-Site Source Recovery Project can take possession and dispose of some of the unwanted transuranic sources at the Waste Isolation Pilot Plant (WIPP). However, there will be no path forward for states outside of the two compacts for disposal of their non-transuranic LLW. A solution that has been much discussed, debated and researched, but has not been put into wide scale practice, is the borehole disposal concept. It is the author's position that companies that drill and explore for oil have been disposing of sources in borehole-like structures for years. It should be noted that these companies are not purposely disposing of these sources, but the sources are irretrievable and must be abandoned. Additionally, there are Nuclear Regulatory Commission (NRC) regulations that must be followed to seal the well that contains the lost and abandoned source. According to the NRC Event Notification Reports database, there were a minimum of 29 reports of lost and abandoned sources in oil wells between December 1999 and October 2006. The sources were lost at depths between 2,018-18,887 feet, or 600-5,750 meters. The companies that are performing explorations with the aid of sealed radiological sources must follow regulation 10 CFR Part 39. Subsection 15 outlines the procedures that must be followed if sources are determined to be irretrievable and abandoned in place. If the NRC allows and has regulations in place for oil companies, why can't states and/or companies be allowed to dispose of LLW in a similar fashion?

  20. Management of Spent and Disused Sealed Radioactive Sources in the Czech Republic - 12124

    SciTech Connect

    Podlaha, J.

    2012-07-01

    The Czech Republic is a country with a well-developed peaceful utilization of nuclear energy and ionizing radiation. Sealed Radioactive Sources (further also SRS) are broadly used in many areas in the Czech Republic, e.g. in research, industry, medicine, education, agriculture, etc. Legislation in the field of ionizing radiation source utilization has been fully harmonized with European Community legislation. SRS utilization demands a proper system which must ensure the safe use of SRS, including the management of disused (spent) and orphaned SRS. In the Czech Republic, a comprehensive system of SRS management has been established that is comparable with systems in other developed countries. The system covers both legal and institutional aspects. The Central Register of Ionizing Radiation Sources is an important part of the system. It is a tracking system that covers all activities related to SRS, from their production or import to the end of their use (recycling or disposal). Many spent SRS are recycled and can be used for other purposes after inspection, repacking or reprocessing. When the disused SRS are not intended for further use, they are managed as radioactive waste (RAW). The system of SRS management also ensures the suitable resolution of situations connected with improper SRS handling (in the case of orphaned sources, accidents, etc.). (author)

  1. Shale disposal of U.S. high-level radioactive waste.

    SciTech Connect

    Sassani, David Carl; Stone, Charles Michael; Hansen, Francis D.; Hardin, Ernest L.; Dewers, Thomas A.; Martinez, Mario J.; Rechard, Robert Paul; Sobolik, Steven Ronald; Freeze, Geoffrey A.; Cygan, Randall Timothy; Gaither, Katherine N.; Holland, John Francis; Brady, Patrick Vane

    2010-05-01

    This report evaluates the feasibility of high-level radioactive waste disposal in shale within the United States. The U.S. has many possible clay/shale/argillite basins with positive attributes for permanent disposal. Similar geologic formations have been extensively studied by international programs with largely positive results, over significant ranges of the most important material characteristics including permeability, rheology, and sorptive potential. This report is enabled by the advanced work of the international community to establish functional and operational requirements for disposal of a range of waste forms in shale media. We develop scoping performance analyses, based on the applicable features, events, and processes identified by international investigators, to support a generic conclusion regarding post-closure safety. Requisite assumptions for these analyses include waste characteristics, disposal concepts, and important properties of the geologic formation. We then apply lessons learned from Sandia experience on the Waste Isolation Pilot Project and the Yucca Mountain Project to develop a disposal strategy should a shale repository be considered as an alternative disposal pathway in the U.S. Disposal of high-level radioactive waste in suitable shale formations is attractive because the material is essentially impermeable and self-sealing, conditions are chemically reducing, and sorption tends to prevent radionuclide transport. Vertically and laterally extensive shale and clay formations exist in multiple locations in the contiguous 48 states. Thermal-hydrologic-mechanical calculations indicate that temperatures near emplaced waste packages can be maintained below boiling and will decay to within a few degrees of the ambient temperature within a few decades (or longer depending on the waste form). Construction effects, ventilation, and the thermal pulse will lead to clay dehydration and deformation, confined to an excavation disturbed zone within

  2. Monitoring technologies for ocean disposal of radioactive waste

    SciTech Connect

    Triplett, M.B.; Solomon, K.A.; Bishop, C.B.; Tyce, R.C.

    1982-01-01

    The feasibility of using carefully selected subseabed locations to permanently isolate high level radioactive wastes at ocean depths greater than 4000 meters is discussed. Disposal at several candidate subseabed areas is being studied because of the long term geologic stability of the sediments, remoteness from human activity, and lack of useful natural resources. While the deep sea environment is remote, it also poses some significant challenges for the technology required to survey and monitor these sites, to identify and pinpoint container leakage should it occur, and to provide the environmental information and data base essential to determining the probable impacts of any such occurrence. Objectives and technical approaches to aid in the selective development of advanced technologies for the future monitoring of nuclear low level and high level waste disposal in the deep seabed are presented. Detailed recommendations for measurement and sampling technology development needed for deep seabed nuclear waste monitoring are also presented.

  3. Site characterization for LIL radioactive waste disposal in Romania

    SciTech Connect

    Diaconu, D. R.; Birdsell, K. H.; Witkowski, M. S.

    2001-01-01

    Recent studies in radioactive waste management in Romania have focussed mainly on the disposal of low and intermediate level waste from the operation of the new nuclear power plant at Cernavoda. Following extensive geological, hydrological, seismological, physical and chemical investigations, a disposal site at Saligny has been selected. This paper presents description of the site at Saligny as well as the most important results of the site characterisation. These are reflected in the three-dimensional, stratigraphical representation of the loess and clay layers and in representative parameter values for the main layers. Based on these data, the simulation of the background, unsaturated-zone water flow at the Saligny site, calculated by the FEHM code, is in a good agreement with the measured moisture profile.

  4. Process for disposal of aqueous solutions containing radioactive isotopes

    DOEpatents

    Colombo, Peter; Neilson, Jr., Robert M.; Becker, Walter W.

    1979-01-01

    A process for disposing of radioactive aqueous waste solutions whereby the waste solution is utilized as the water of hydration to hydrate densified powdered portland cement in a leakproof container; said waste solution being dispersed without mechanical inter-mixing in situ in said bulk cement, thereafter the hydrated cement body is impregnated with a mixture of a monomer and polymerization catalyst to form polymer throughout the cement body. The entire process being carried out while maintaining the temperature of the components during the process at a temperature below 99.degree. C. The container containing the solid polymer-impregnated body is thereafter stored at a radioactive waste storage dump such as an underground storage dump.

  5. Investigations of Near-Field Thermal-Hydrologic-Mechanical-Chemical Models for Radioactive Waste Disposal in Clay/Shale Rock

    SciTech Connect

    Liu, H.H.; Li, L.; Zheng, L.; Houseworth, J.E.; Rutqvist, J.

    2011-06-20

    Clay/shale has been considered as potential host rock for geological disposal of high-level radioactive waste throughout the world, because of its low permeability, low diffusion coefficient, high retention capacity for radionuclides, and capability to self-seal fractures. For example, Callovo-Oxfordian argillites at the Bure site, France (Fouche et al., 2004), Toarcian argillites at the Tournemire site, France (Patriarche et al., 2004), Opalinus Clay at the Mont Terri site, Switzerland (Meier et al., 2000), and Boom clay at the Mol site, Belgium (Barnichon and Volckaert, 2003) have all been under intensive scientific investigation (at both field and laboratory scales) for understanding a variety of rock properties and their relationships to flow and transport processes associated with geological disposal of radioactive waste. Figure 1-1 presents the distribution of clay/shale formations within the USA.

  6. Directions in low-level radioactive waste management: A brief history of commercial low-level radioactive waste disposal

    SciTech Connect

    Not Available

    1990-10-01

    This report presents a history of commercial low-level radioactive waste management in the United States, with emphasis on the history of six commercially operated low-level radioactive waste disposal facilities. The report includes a brief description of important steps that have been taken during the 1980s to ensure the safe disposal of low-level waste in the 1990s and beyond. These steps include the issuance of Title 10 Code of Federal Regulations Part 61, Licensing Requirements for the Land Disposal of Radioactive Waste, the Low-Level Radioactive Waste Policy Act of 1980, the Low-Level Radioactive Waste Policy Amendments Act of 1985, and steps taken by states and regional compacts to establish additional disposal sites. 42 refs., 13 figs., 1 tab.

  7. Submergible barge retrievable storage and permanent disposal system for radioactive waste

    DOEpatents

    Goldsberry, Fred L.; Cawley, William E.

    1981-01-01

    A submergible barge and process for submerging and storing radioactive waste material along a seabed. A submergible barge receives individual packages of radwaste within segregated cells. The cells are formed integrally within the barge, preferably surrounded by reinforced concrete. The cells are individually sealed by a concrete decking and by concrete hatch covers. Seawater may be vented into the cells for cooling, through an integral vent arrangement. The vent ducts may be attached to pumps when the barge is bouyant. The ducts are also arranged to promote passive ventilation of the cells when the barge is submerged. Packages of the radwaste are loaded into individual cells within the barge. The cells are then sealed and the barge is towed to the designated disposal-storage site. There, the individual cells are flooded and the barge will begin descent controlled by a powered submarine control device to the seabed storage site. The submerged barge will rest on the seabed permanently or until recovered by a submarine control device.

  8. Risk methodology for geologic disposal of radioactive waste

    SciTech Connect

    Cranwell, R.M.; Campbell, J.E.; Ortiz, N.R. ); Guzowski, R.V. )

    1990-04-01

    This report contains the description of a procedure for selecting scenarios that are potentially important to the isolation of high- level radioactive wastes in deep geologic formations. In this report, the term scenario is used to represent a set of naturally occurring and/or human-induced conditions that represent realistic future states of the repository, geologic systems, and ground-water flow systems that might affect the release and transport of radionuclides from the repository to humans. The scenario selection procedure discussed in this report is demonstrated by applying it to the analysis of a hypothetical waste disposal site containing a bedded-salt formation as the host medium for the repository. A final set of 12 scenarios is selected for this site. 52 refs., 48 figs., 5 tabs.

  9. New aspects for the evaluation of radioactive waste disposal methods

    SciTech Connect

    Seiler, F.A.; Alvarez, J.L.

    1996-12-31

    For the performance assessment of radioactive and hazardous waste disposal sites, risk assessments are usually performed for the long term, i.e., over an interval in space and time for which one can predict movement and behavior of toxic agents in the environment. This approach is based on at least three implicit assumptions: One, that the engineering layout will take care of the immediate endangerment of potential receptors; two, that one has carefully evaluated just how far out in space and time the models can be extrapolated, and three, that one can evaluate potential health effects for very low exposures. A few of these aspects will be discussed here in the framework of the scientific method.

  10. Radioactive waste disposal characteristics of candidate tokamak demonstration reactors

    SciTech Connect

    Hoffman, E.A.; Stacey, W.M.; Hertel, N.E.

    1998-08-01

    Results from the current physics, materials and blanket R and D programs are combined with physics and engineering design constraints to characterize candidate tokamak demonstration plant (DEMO) designs. Blanket designs based on the principal structural materials, breeding materials and coolants being developed for the DEMO were adapted from the literature. Neutron flux and activation calculations were performed, and several radioactive waste disposal indices were evaluated, for each design. Of the primary low-activation structural materials under development in the US, it appears that vanadium and ferritic steel alloys, and possibly silicon carbide, could lead to DEMO designs which could satisfy realistic low-level waste (LLW) criteria, provided that impurities can be controlled within plausible limits. Allowable LLW concentrations are established for the limiting alloying and impurity elements. All breeding materials and neutron multipliers considered meet the LLW criterion.

  11. Seismic considerations in sealing a potential high-level radioactive waste repository

    SciTech Connect

    Fernandez, J.A.; Richardson, A.M.; Lin, Ming

    1993-09-01

    The potential repository system is intended to isolate high-level radioactive waste at Yucca Mountain according the performance objective--10 CFR 60.112. One subsystem that may contribute to achieving this objective is the sealing subsystem. This subsystem is comprised of sealing components in the shafts, ramps, underground network of drifts, and the exploratory boreholes. Sealing components can be rigid, as in the case of a shaft seal, or can be more compressible, as in the case of drift fill comprised of mined rockfill. This paper presents the preliminary seismic response of discrete sealing components in welded and nonwelded tuff. Special consideration is given to evaluating the stress in the seal, and the behavior of the interface between the seal and the rock. The seismic responses are computed using both static and dynamic analyses. Also presented is an evaluation of the maximum seismic response encountered by a drift seal with respect to the angle of incidence of the seismic wave. Mitigation strategies and seismic design considerations are proposed which can potentially enhance the overall response of the sealing component and subsequently, the performance of the overall repository system.

  12. Spanish methodological approach for biosphere assessment of radioactive waste disposal.

    PubMed

    Agüero, A; Pinedo, P; Cancio, D; Simón, I; Moraleda, M; Pérez-Sánchez, D; Trueba, C

    2007-10-01

    The development of radioactive waste disposal facilities requires implementation of measures that will afford protection of human health and the environment over a specific temporal frame that depends on the characteristics of the wastes. The repository design is based on a multi-barrier system: (i) the near-field or engineered barrier, (ii) far-field or geological barrier and (iii) the biosphere system. Here, the focus is on the analysis of this last system, the biosphere. A description is provided of conceptual developments, methodological aspects and software tools used to develop the Biosphere Assessment Methodology in the context of high-level waste (HLW) disposal facilities in Spain. This methodology is based on the BIOMASS "Reference Biospheres Methodology" and provides a logical and systematic approach with supplementary documentation that helps to support the decisions necessary for model development. It follows a five-stage approach, such that a coherent biosphere system description and the corresponding conceptual, mathematical and numerical models can be built. A discussion on the improvements implemented through application of the methodology to case studies in international and national projects is included. Some facets of this methodological approach still require further consideration, principally an enhanced integration of climatology, geography and ecology into models considering evolution of the environment, some aspects of the interface between the geosphere and biosphere, and an accurate quantification of environmental change processes and rates. PMID:17588645

  13. Modeling Coupled Processes in Clay Formations for Radioactive Waste Disposal

    SciTech Connect

    Liu, Hui-Hai; Rutqvist, Jonny; Zheng, Liange; Sonnenthal, Eric; Houseworth, Jim; Birkholzer, Jens

    2010-08-31

    As a result of the termination of the Yucca Mountain Project, the United States Department of Energy (DOE) has started to explore various alternative avenues for the disposition of used nuclear fuel and nuclear waste. The overall scope of the investigation includes temporary storage, transportation issues, permanent disposal, various nuclear fuel types, processing alternatives, and resulting waste streams. Although geologic disposal is not the only alternative, it is still the leading candidate for permanent disposal. The realm of geologic disposal also offers a range of geologic environments that may be considered, among those clay shale formations. Figure 1-1 presents the distribution of clay/shale formations within the USA. Clay rock/shale has been considered as potential host rock for geological disposal of high-level nuclear waste throughout the world, because of its low permeability, low diffusion coefficient, high retention capacity for radionuclides, and capability to self-seal fractures induced by tunnel excavation. For example, Callovo-Oxfordian argillites at the Bure site, France (Fouche et al., 2004), Toarcian argillites at the Tournemire site, France (Patriarche et al., 2004), Opalinus clay at the Mont Terri site, Switzerland (Meier et al., 2000), and Boom clay at Mol site, Belgium (Barnichon et al., 2005) have all been under intensive scientific investigations (at both field and laboratory scales) for understanding a variety of rock properties and their relations with flow and transport processes associated with geological disposal of nuclear waste. Clay/shale formations may be generally classified as indurated and plastic clays (Tsang et al., 2005). The latter (including Boom clay) is a softer material without high cohesion; its deformation is dominantly plastic. For both clay rocks, coupled thermal, hydrological, mechanical and chemical (THMC) processes are expected to have a significant impact on the long-term safety of a clay repository. For

  14. Life-Cycle Cost Study for a Low-Level Radioactive Waste Disposal Facility in Texas

    SciTech Connect

    B. C. Rogers; P. L. Walter; R. D. Baird

    1999-08-01

    This report documents the life-cycle cost estimates for a proposed low-level radioactive waste disposal facility near Sierra Blanca, Texas. The work was requested by the Texas Low-Level Radioactive Waste Disposal Authority and performed by the National Low-Level Waste Management Program with the assistance of Rogers and Associates Engineering Corporation.

  15. 48 CFR 945.603-71 - Disposal of radioactively contaminated personal property.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Contractor Inventory 945.603-71 Disposal of radioactively contaminated personal property. Special procedures regarding the disposal of radioactively contaminated property may be found at 41 CFR 109-45.50. ... contaminated personal property. 945.603-71 Section 945.603-71 Federal Acquisition Regulations System...

  16. Gas generation from low-level radioactive waste: Concerns for disposal

    SciTech Connect

    Siskind, B.

    1992-04-01

    The Advisory Committee on Nuclear Waste (ACNW) has urged the Nuclear Regulatory Commission (NRC) to reexamine the topic of hydrogen gas generation from low-level radioactive waste (LLW) in closed spaces to ensure that the slow buildup of hydrogen from water-bearing wastes in sealed containers does not become a problem for long-term safe disposal. Brookhaven National Laboratory (BNL) has prepared a report, summarized in this paper, for the NRC to respond to these concerns. The paper discusses the range of values for G(H{sub 2}) reported for materials of relevance to LLW disposal; most of these values are in the range of 0.1 to 0.6. Most studies of radiolytic hydrogen generation indicate a leveling off of pressurization, probably because of chemical kinetics involving, in many cases, the radiolysis of water within the waste. Even if no leveling off occurs, realistic gas leakage rates (indicating poor closure by gaskets on drums and liners) will result in adequate relief of pressure for radiolytic gas generation from the majority of commercial sector LLW packages. Biodegradative gas generation, however, could pose a pressurization hazard even at realistic gas leakage rates. Recommendations include passive vents on LLW containers (as already specified for high integrity containers) and upper limits to the G values and/or the specific activity of the LLW.

  17. Gas generation from low-level radioactive waste: Concerns for disposal

    SciTech Connect

    Siskind, B.

    1992-01-01

    The Advisory Committee on Nuclear Waste (ACNW) has urged the Nuclear Regulatory Commission (NRC) to reexamine the topic of hydrogen gas generation from low-level radioactive waste (LLW) in closed spaces to ensure that the slow buildup of hydrogen from water-bearing wastes in sealed containers does not become a problem for long-term safe disposal. Brookhaven National Laboratory (BNL) has prepared a report, summarized in this paper, for the NRC to respond to these concerns. The paper discusses the range of values for G(H{sub 2}) reported for materials of relevance to LLW disposal; most of these values are in the range of 0.1 to 0.6. Most studies of radiolytic hydrogen generation indicate a leveling off of pressurization, probably because of chemical kinetics involving, in many cases, the radiolysis of water within the waste. Even if no leveling off occurs, realistic gas leakage rates (indicating poor closure by gaskets on drums and liners) will result in adequate relief of pressure for radiolytic gas generation from the majority of commercial sector LLW packages. Biodegradative gas generation, however, could pose a pressurization hazard even at realistic gas leakage rates. Recommendations include passive vents on LLW containers (as already specified for high integrity containers) and upper limits to the G values and/or the specific activity of the LLW.

  18. Greater-confinement disposal of low-level radioactive wastes

    SciTech Connect

    Trevorrow, L.E.; Gilbert, T.L.; Luner, C.; Merry-Libby, P.A.; Meshkov, N.K.; Yu, C.

    1985-01-01

    Low-level radioactive wastes include a broad spectrum of wastes that have different radionuclide concentrations, half-lives, and physical and chemical properties. Standard shallow-land burial practice can provide adequate protection of public health and safety for most low-level wastes, but a small volume fraction (about 1%) containing most of the activity inventory (approx.90%) requires specific measures known as ''greater-confinement disposal'' (GCD). Different site characteristics and different waste characteristics - such as high radionuclide concentrations, long radionuclide half-lives, high radionuclide mobility, and physical or chemical characteristics that present exceptional hazards - lead to different GCD facility design requirements. Facility design alternatives considered for GCD include the augered shaft, deep trench, engineered structure, hydrofracture, improved waste form, and high-integrity container. Selection of an appropriate design must also consider the interplay between basic risk limits for protection of public health and safety, performance characteristics and objectives, costs, waste-acceptance criteria, waste characteristics, and site characteristics. This paper presents an overview of the factors that must be considered in planning the application of methods proposed for providing greater confinement of low-level wastes. 27 refs.

  19. Nuclear reactor sealing system

    DOEpatents

    McEdwards, James A.

    1983-01-01

    A liquid metal-cooled nuclear reactor sealing system. The nuclear reactor includes a vessel sealed at its upper end by a closure head. The closure head comprises at least two components, one of which is rotatable; and the two components define an annulus therebetween. The sealing system includes at least a first and second inflatable seal disposed in series in an upper portion of the annulus. The system further includes a dip seal extending into a body of insulation located adjacent a bottom portion of the closure head. The dip seal comprises a trough formed by a lower portion of one of the components, and a seal blade pendently supported from the other component and extending downwardly into the trough. A body of liquid metal is contained in the trough which submerges a portion of the seal blade. The seal blade is provided with at least one aperture located above the body of liquid metal for providing fluid communication between the annulus intermediate the dip seal and the inflatable seals, and a body of cover gas located inside the vessel. There also is provided means for introducing a purge gas into the annulus intermediate the inflatable seals and the seal blade. The purge gas is introduced in an amount sufficient to substantially reduce diffusion of radioactive cover gas or sodium vapor up to the inflatable seals. The purge gas mixes with the cover gas in the reactor vessel where it can be withdrawn from the vessel for treatment and recycle to the vessel.

  20. Thermal-mechanical modeling of deep borehole disposal of high-level radioactive waste.

    SciTech Connect

    Arnold, Bill Walter; Hadgu, Teklu

    2010-12-01

    Disposal of high-level radioactive waste, including spent nuclear fuel, in deep (3 to 5 km) boreholes is a potential option for safely isolating these wastes from the surface and near-surface environment. Existing drilling technology permits reliable and cost-effective construction of such deep boreholes. Conditions favorable for deep borehole disposal in crystalline basement rocks, including low permeability, high salinity, and geochemically reducing conditions, exist at depth in many locations, particularly in geologically stable continental regions. Isolation of waste depends, in part, on the effectiveness of borehole seals and potential alteration of permeability in the disturbed host rock surrounding the borehole. Coupled thermal-mechanical-hydrologic processes induced by heat from the radioactive waste may impact the disturbed zone near the borehole and borehole wall stability. Numerical simulations of the coupled thermal-mechanical response in the host rock surrounding the borehole were conducted with three software codes or combinations of software codes. Software codes used in the simulations were FEHM, JAS3D, Aria, and Adagio. Simulations were conducted for disposal of spent nuclear fuel assemblies and for the higher heat output of vitrified waste from the reprocessing of fuel. Simulations were also conducted for both isotropic and anisotropic ambient horizontal stress in the host rock. Physical, thermal, and mechanical properties representative of granite host rock at a depth of 4 km were used in the models. Simulation results indicate peak temperature increases at the borehole wall of about 30 C and 180 C for disposal of fuel assemblies and vitrified waste, respectively. Peak temperatures near the borehole occur within about 10 years and decline rapidly within a few hundred years and with distance. The host rock near the borehole is placed under additional compression. Peak mechanical stress is increased by about 15 MPa (above the assumed ambient

  1. Thermal-Mechanical Modeling of Deep Borehole Disposal of High-Level Radioactive Waste

    NASA Astrophysics Data System (ADS)

    Arnold, B. W.; Clayton, D. J.; Herrick, C. G.; Hadgu, T.

    2010-12-01

    Disposal of high-level radioactive waste, including spent nuclear fuel, in deep (3 to 5 km) boreholes is a potential option for safely isolating these wastes from the surface and near-surface environment. Existing drilling technology permits reliable and cost-effective construction of such deep boreholes. Conditions favorable for deep borehole disposal in crystalline basement rocks, including low permeability, high salinity, and geochemically reducing conditions, exist at depth in many locations, particularly in geologically stable continental regions. Isolation of waste depends, in part, on the effectiveness of borehole seals and potential alteration of permeability in the disturbed host rock surrounding the borehole. Coupled thermal-mechanical-hydrologic processes induced by heat from the radioactive waste may impact the disturbed zone near the borehole and borehole wall stability. Numerical simulations of the coupled thermal-mechanical response in the host rock surrounding the borehole were conducted with three software codes or combinations of software codes. Software codes used in the simulations were FEHM, JAS3D, Aria, and Adagio. Simulations were conducted for disposal of spent nuclear fuel assemblies and for the higher heat output of vitrified waste from the reprocessing of fuel. Simulations were also conducted for both isotropic and anisotropic ambient horizontal stress in the host rock. Physical, thermal, and mechanical properties representative of granite host rock at a depth of 4 km were used in the models. Simulation results indicate peak temperature increases at the borehole wall of about 30 °C and 180 °C for disposal of fuel assemblies and vitrified waste, respectively. Peak temperatures near the borehole occur within about 10 years and decline rapidly within a few hundred years and with distance. The host rock near the borehole is placed under additional compression. Peak mechanical stress is increased by about 15 MPa (above the assumed ambient

  2. Development of low-level radioactive waste disposal capacity in the United States - progress or stalemate?

    SciTech Connect

    Devgun, J.S.; Larson, G.S.

    1995-12-31

    It has been fifteen years since responsibility for the disposal of commercially generated low-level radioactive waste (LLW) was shifted to the states by the United States Congress through the Low-Level Radioactive Waste Policy Act of 1980 (LLRWPA). In December 1985, Congress revisited the issue and enacted the Low-Level Radioactive Waste Policy Amendments Act of 1985 (LLRWPAA). No new disposal sites have opened yet, however, and it is now evident that disposal facility development is more complex, time-consuming, and controversial than originally anticipated. For a nation with a large nuclear power industry, the lack of availability of LLW disposal capacity coupled with a similar lack of high-level radioactive waste disposal capacity could adversely affect the future viability of the nuclear energy option. The U.S. nuclear power industry, with 109 operating reactors, generates about half of the LLW shipped to commercial disposal sites and faces dwindling access to waste disposal sites and escalating waste management costs. The other producers of LLW - industries, government (except the defense related research and production waste), academic institutions, and medical institutions that account for the remaining half of the commercial LLW - face the same storage and cost uncertainties. This paper will summarize the current status of U.S. low-level radioactive waste generation and the status of new disposal facility development efforts by the states. The paper will also examine the factors that have contributed to delays, the most frequently suggested alternatives, and the likelihood of change.

  3. Leveraging Radioactive Waste Disposal at WIPP for Science

    NASA Astrophysics Data System (ADS)

    Rempe, N. T.

    2008-12-01

    Salt mines are radiologically much quieter than other underground environments because of ultra-low concentrations of natural radionuclides (U, Th, and K) in the host rock; therefore, the Waste Isolation Pilot Plant (WIPP), a government-owned, 655m deep geologic repository that disposes of radioactive waste in thick salt near Carlsbad, New Mexico, has for the last 15 years hosted highly radiation-sensitive experiments. Incidentally, Nature started her own low background experiment 250ma ago, preserving viable bacteria, cellulose, and DNA in WIPP salt. The Department of Energy continues to make areas of the WIPP underground available for experiments, freely offering its infrastructure and access to this unique environment. Even before WIPP started disposing of waste in 1999, the Room-Q alcove (25m x 10m x 4m) housed a succession of small experiments. They included development and calibration of neutral-current detectors by Los Alamos National Laboratory (LANL) for the Sudbury Neutrino Observatory, a proof-of-concept by Ohio State University of a flavor-sensitive neutrino detector for supernovae, and research by LANL on small solid- state dark matter detectors. Two currently active experiments support the search for neutrino-less double beta decay as a tool to better define the nature and mass of the neutrino. That these delicate experiments are conducted in close vicinity to, but not at all affected by, megacuries of radioactive waste reinforces the safety argument for the repository. Since 2003, the Majorana collaboration is developing and testing various detector designs inside a custom- built clean room in the Room-Q alcove. Already low natural background readings are reduced further by segmenting the germanium detectors, which spatially and temporally discriminates background radiation. The collaboration also demonstrated safe copper electro-forming underground, which minimizes cosmogenic background in detector assemblies. The largest currently used experimental

  4. Environmental monitoring of low-level radioactive waste disposal facility

    SciTech Connect

    Shum, E.Y.; Starmer, R.J.; Young, M.H.

    1989-12-01

    This branch technical position (BTP) paper on the environmental monitoring program for a low-level radioactive waste disposal facility provides general guidance on what is required by Section 61.53 of Title 10 of the Code of Federal Regulations (10 CFR) of applicants submitting a license application for such a facility. In general, the environmental monitoring program consists of three phases: preoperational, operational, and postoperational. Each phase of the monitoring program should be designed to fulfill the specific objectives defined in the BTP paper. During the preoperational phase, the objectives of the program are to provide site characterization information, to demonstrate site suitability and acceptability, to obtain background or baseline information, and to provide a record for public information. During the operational phase, the emphasis on measurement shifts. Monitoring data are obtained to provide early warning of releases and to document compliance with regulations, the dose limits of 10 CFR Part 61, or applicable standards of the US Environmental Protection Agency. Data are also used to update important pathway parameters to improve predictions of site performance and to provide a record of performance for public information. The postoperational environmental monitoring program emphasizes measurements to demonstrate compliance with the site-closure requirements and continued compliance with the performance objective in regard to the release of radionuclides to the environment. The data are used to support evaluation of long-term effects on the general public and for public information. Guidance is also provided in the BTP paper on the choice of which constituents to measure, setting action levels, relating measurements to appropriate actions in a corrective action plan, and quality assurance.

  5. TRANSPORT OF LOW-LEVEL RADIOACTIVE SOIL AT DEEP-OCEAN DISPOSAL SITE

    EPA Science Inventory

    Transport studies were conducted to assess ocean disposal of soil contaminated with low-level natural radioisotopes. he experimental approach involved characterization of the soil for parameters affecting transport and fate of radionuclides- Radioactivity was associated with disc...

  6. Commercial disposal options for Idaho National Engineering Laboratory low-level radioactive waste

    SciTech Connect

    Porter, C.L.; Widmayer, D.A.

    1995-09-01

    The Idaho National Engineering Laboratory (INEL) is a Department of Energy (DOE)-owned, contractor-operated site. Significant quantities of low-level radioactive waste (LLW) have been generated and disposed of onsite at the Radioactive Waste Management Complex (RWMC). The INEL expects to continue generating LLW while performing its mission and as aging facilities are decommissioned. An on-going Performance Assessment process for the RWMC underscores the potential for reduced or limited LLW disposal capacity at the existing onsite facility. In order to properly manage the anticipated amount of LLW, the INEL is investigating various disposal options. These options include building a new facility, disposing the LLW at other DOE sites, using commercial disposal facilities, or seeking a combination of options. This evaluation reports on the feasibility of using commercial disposal facilities.

  7. Policy analysis of the low-level radioactive waste-disposal problem in the United States

    SciTech Connect

    Maloney, S.; Sterman, J.D.

    1982-05-01

    Federal policy governing the control of low-level radioactive waste resulting from commercial nuclear reactor operations is currently undergoing development. A simulation model examines the effects of various options, including volume reduction, local waste-disposal limits, the use of the U. S. Department of Energy sites, and expedited licensing of disposal sites.

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

    SciTech Connect

    Pretzsch, Gunter; Salewski, Peter; Sogalla, Martin

    2013-07-01

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

  9. Radioactive waste disposal implications of extending Part IIA of the Environmental Protection Act to cover radioactively contaminated land.

    PubMed

    Nancarrow, D J; White, M M

    2004-03-01

    A short study has been carried out of the potential radioactive waste disposal issues associated with the proposed extension of Part IIA of the Environmental Protection Act 1990 to include radioactively contaminated land, where there is no other suitable existing legislation. It was found that there is likely to be an availability problem with respect to disposal at landfills of the radioactive wastes arising from remediation. This is expected to be principally wastes of high volume and low activity (categorised as low level waste (LLW) and very low level waste (VLLW)). The availability problem results from a lack of applications by landfill operators for authorisation to accept LLW wastes for disposal. This is apparently due to perceived adverse publicity associated with the consultation process for authorisation coupled with uncertainty over future liabilities. Disposal of waste as VLLW is limited both by questions over volumes that may be acceptable and, more fundamentally, by the likely alpha activity of wastes (originating from radium and thorium operations). Authorised on-site disposal has had little attention in policy and guidance in recent years, but may have a part to play, especially if considered commercially attractive. Disposal at BNFL's near surface disposal facility for LLW at Drigg is limited to wastes for which there are no practical alternative disposal options (and preference has been given to operational type wastes). Therefore, wastes from the radioactively contaminated land (RCL) regime are not obviously attractive for disposal to Drigg. Illustrative calculations have been performed based on possible volumes and activities of RCL arisings (and assuming Drigg's future volumetric disposal capacity is 950,000 m3). These suggest that wastes arising from implementing the RCL regime, if all disposed to Drigg, would not represent a significant fraction of the volumetric capacity of Drigg, but could have a significant impact on the radiological

  10. 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.

  11. Low-level radioactive waste disposal technologies used outside the United States

    SciTech Connect

    Templeton, K.J.; Mitchell, S.J.; Molton, P.M.; Leigh, I.W.

    1994-01-01

    Low-level radioactive waste (LLW) disposal technologies are an integral part of the waste management process. In the United States, commercial LLW disposal is the responsibility of the State or groups of States (compact regions). The United States defines LLW as all radioactive waste that is not classified as spent nuclear fuel, high- level radioactive waste, transuranic waste, or by-product material as defined in Section II(e)(2) of the Atomic Energy Act. LLW may contain some long-lived components in very low concentrations. Countries outside the United States, however, may define LLW differently and may use different disposal technologies. This paper outlines the LLW disposal technologies that are planned or being used in Canada, China, Finland, France, Germany, Japan, Sweden, Taiwan, and the United Kingdom (UK).

  12. Expediting the commercial disposal option: Low-level radioactive waste shipments from the Mound Plant

    SciTech Connect

    Rice, S.; Rothman, R.

    1995-12-31

    In April, Envirocare of Utah, Inc., successfully commenced operation of its mixed waste treatment operation. A mixed waste which was (a) radioactive, (b) listed as a hazardous waste under the Resource Conservation and Recovery Act (RCRA), and (c) prohibited from land disposal was treated using Envirocare`s full-scale Mixed Waste Treatment Facility. The treatment system involved application of chemical fixation/stabilization technologies to reduce the leachability of the waste to meet applicable concentration-based RCRA treatment standards. In 1988, Envirocare became the first licensed facility for the disposal of naturally occurring radioactive material. In 1990, Envirocare received a RCRA Part B permit for commercial mixed waste storage and disposal. In 1994, Envirocare was awarded a contract for the disposal of DOE mixed wastes. Envirocare`s RCRA Part B permit allows for the receipt, storage, treatment, and disposal of mixed wastes that do not meet the land-disposal treatment standards of 40 CFR (Code of Federal Regulations) 268. Envirocare has successfully received, managed, and disposed of naturally occurring radioactive material, low-activity radioactive waste, and mixed waste from government and private generators.

  13. 10 CFR 40.27 - General license for custody and long-term care of residual radioactive material disposal sites.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... radioactive material disposal sites. 40.27 Section 40.27 Energy NUCLEAR REGULATORY COMMISSION DOMESTIC... residual radioactive material disposal sites. (a) A general license is issued for the custody of and long... lease any subsurface mineral rights associated with land on which residual radioactive materials...

  14. 10 CFR 40.27 - General license for custody and long-term care of residual radioactive material disposal sites.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... radioactive material disposal sites. 40.27 Section 40.27 Energy NUCLEAR REGULATORY COMMISSION DOMESTIC... residual radioactive material disposal sites. (a) A general license is issued for the custody of and long... lease any subsurface mineral rights associated with land on which residual radioactive materials...

  15. 10 CFR 40.27 - General license for custody and long-term care of residual radioactive material disposal sites.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... radioactive material disposal sites. 40.27 Section 40.27 Energy NUCLEAR REGULATORY COMMISSION DOMESTIC... residual radioactive material disposal sites. (a) A general license is issued for the custody of and long... lease any subsurface mineral rights associated with land on which residual radioactive materials...

  16. 10 CFR 40.27 - General license for custody and long-term care of residual radioactive material disposal sites.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... radioactive material disposal sites. 40.27 Section 40.27 Energy NUCLEAR REGULATORY COMMISSION DOMESTIC... residual radioactive material disposal sites. (a) A general license is issued for the custody of and long... lease any subsurface mineral rights associated with land on which residual radioactive materials...

  17. 10 CFR 40.27 - General license for custody and long-term care of residual radioactive material disposal sites.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... radioactive material disposal sites. 40.27 Section 40.27 Energy NUCLEAR REGULATORY COMMISSION DOMESTIC... residual radioactive material disposal sites. (a) A general license is issued for the custody of and long... lease any subsurface mineral rights associated with land on which residual radioactive materials...

  18. Developing operating procedures for a low-level radioactive waste disposal facility

    SciTech Connect

    Sutherland, A.A.; Miner, G.L.; Grahn, K.F.; Pollard, C.G.

    1993-10-01

    This document is intended to assist persons who are developing operating and emergency procedures for a low-level radioactive waste disposal facility. It provides 25 procedures that are considered to be relatively independent of the characteristics of a disposal facility site, the facility design, and operations at the facility. These generic procedures should form a good starting point for final procedures on their subjects for the disposal facility. In addition, this document provides 55 annotated outlines of other procedures that are common to disposal facilities. The annotated outlines are meant as checklists to assist the developer of new procedures.

  19. Remediation of a Former USAF Radioactive Material Disposal Site

    SciTech Connect

    Hoffman, D. E.; Cushman, M; Tupyi, B.; Lambert, J.

    2003-02-25

    This paper describes the remediation of a low-level radiological waste burial site located at the former James Connally Air Force Base in Waco, Texas. Burial activities at the site occurred during the 1950's when the property was under the ownership of the United States Air Force. Included is a discussion of methods and strategies that were used to successfully exhume and characterize the wastes for proper disposal at offsite disposal facilities. Worker and environmental protection measures are also described. Information gained from this project may be used at other similar project sites. A total of nine burial tubes had been identified for excavation, characterization, and removal from the site. The disposal tubes were constructed of 4-ft lengths of concrete pipe buried upright with the upper ends flush with ground surface. Initial ground level observations of the burial tubes indicated that some weathering had occurred; however, the condition of the subsurface portions of the tubes was unknown. Soil excavation occurred in 1-foot lifts in order that the tubes could be inspected and to allow for characterization of the soils at each stage of the excavation. Due to the weight of the concrete pipe and the condition of the piping joints it was determined that special measures would be required to maintain the tubes intact during their removal. Special tube anchoring and handling methods were required to relocate the tubes from their initial positions to a staging area where they could be further characterized. Characterization of the disposal tubes was accomplished using a combination of gamma spectroscopy and activity mapping methods. Important aspects of the project included the use of specialized excavation and disposal tube reinforcement measures to maintain the disposal tubes intact during excavation, removal and subsequent characterization. The non-intrusive gamma spectroscopy and data logging methods allowed for effective characterization of the wastes while

  20. Study of extraterrestrial disposal of radioactive wastes. Part 1: Space transportation and destination considerations for extraterrestrial disposal of radioactive wastes. [feasibility of using space shuttle

    NASA Technical Reports Server (NTRS)

    Thompson, R. L.; Ramler, J. R.; Stevenson, S. M.

    1974-01-01

    A feasibility study of extraterrestrial disposal of radioactive waste is reported. This report covers the initial work done on only one part of the NASA study, that evaluates and compares possible space destinations and space transportation systems. The currently planned space shuttle was found to be more cost effective than current expendable launch vehicles by about a factor of 2. The space shuttle requires a third stage to perform the waste disposal missions. Depending on the particular mission, this third stage could be either a reusable space tug or an expendable stage such as a Centaur.

  1. Safety and Security of Radioactive Sealed and Disused/Orphan Sources in Ukraine - German Contribution - 13359

    SciTech Connect

    Brasser, Thomas; Hertes, Uwe; Meyer, Thorsten; Uhlenbruck, Hermann; Shevtsov, Alexey

    2013-07-01

    Within the scope of 'Nuclear Security of Radioactive Sources', the German government implemented the modernization of Ukrainian State Production Company's transport and storage facility for radioactive sources (TSF) in Kiev. The overall management of optimizing the physical protection of the storage facility (including the construction of a hot cell for handling the radioactive sources) is currently carried out by the German Federal Foreign Office (AA). AA jointly have assigned Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) mbH, Germany's leading expert institution in the area of nuclear safety and waste management, to implement the project and to ensure transparency by financial and technical monitoring. Sealed radioactive sources are widely used in industry, medicine and research. Their life cycle starts with the production and finally ends with the interim/long-term storage of the disused sources. In Ukraine, IZOTOP is responsible for all radioactive sources throughout their life cycle. IZOTOP's transport and storage facility (TSF) is the only Ukrainian storage facility for factory-fresh radioactive sources up to an activity of about 1 million Ci (3.7 1016 Bq). The TSF is specially designed for the storage and handling of radioactive sources. Storage began in 1968, and is licensed by the Ukrainian state authorities. Beside the outdated state of TSF's physical protection and the vulnerability of the facility linked with it, the lack of a hot cell for handling and repacking radioactive sources on the site itself represents an additional potential hazard. The project, financed by the German Federal Foreign Office, aims to significantly improve the security of radioactive sources during their storage and handling at the TSF site. Main tasks of the project are a) the modernization of the physical protection of the TSF itself in order to prevent any unauthorized access to radioactive sources as well as b) the construction of a hot cell to reduce the number of

  2. Radioactive waste disposal in Germany: no site decision - Keeping competence

    SciTech Connect

    Kienzler, Bernhard; Geckeis, Horst; Gompper, Klaus; Klenze, Reinhardt

    2007-07-01

    The research programme of the Institut fuer Nukleare Entsorgung (INE) at the Forschungszentrum Karlsruhe is dedicated to elaborate the fundamental understanding of radionuclide/actinide interactions with various components of the groundwater and with the relevant host rock materials at disposal relevant trace concentrations. INE's research programme was not biased after enactment of the Gorleben moratorium in 2001. This paper presents current R and D with respect to application in performance assessment/safety case of nuclear waste disposal. Focus is given to the leading role of the institute in various projects within EU framework programmes. (authors)

  3. Potential for Subsidence at the Low-Level Radioactive Waste Disposal Area

    SciTech Connect

    Keck, K.A.; Seitz, R.R.

    2002-09-26

    U.S. Department of Energy (DOE) Order 435.1, Radioactive Waste Management requires that DOE low-level radioactive waste (LLW) disposal facilities receive a Disposal Authorization Statement (DAS) from DOE-Headquarters. The DAS for the LLW disposal facility at the Radioactive Waste Management Complex (RWMC) at the Idaho National Engineering and Environmental Laboratory (INEEL) was granted in April 2000 and included a number of conditions that must be addressed. A maintenance plan (Schuman 2000) was prepared that identifies the tasks to be completed to address the conditions in the DAS as well as a schedule for their completion. The need for a subsidence analysis was one of the conditions identified for the DAS, and thus, a task to prepare a subsidence analysis was included in the maintenance plan. This document provides the information necessary to satisfy that requirement.

  4. Development of Approach for Long-Term Management of Disused Sealed Radioactive Sources - 13630

    SciTech Connect

    Kinker, M.; Reber, E.; Mansoux, H.; Bruno, G.

    2013-07-01

    Radioactive sources are used widely throughout the world in a variety of medical, industrial, research and military applications. When such radioactive sources are no longer used and are not intended to be used for the practice for which an authorization was granted, they are designated as 'disused sources'. Whether appropriate controls are in place during the useful life of a source or not, the end of this useful life is often a turning point after which it is more difficult to ensure the safety and security of the source over time. For various reasons, many disused sources cannot be returned to the manufacturer or the supplier for reuse or recycling. When these attempts fail, disused sources should be declared as radioactive waste and should be managed as such, in compliance with relevant international legal instruments and safety standards. However, disposal remains an unresolved issue in many counties, due to in part to limited public acceptance, insufficient funding, and a lack of practical examples of strategies for determining suitable disposal options. As a result, disused sources are often stored indefinitely at the facilities where they were once used. In order to prevent disused sources from becoming orphan sources, each country must develop and implement a comprehensive waste management strategy that includes disposal of disused sources. The International Atomic Energy Agency (IAEA) fosters international cooperation between countries and encourages the development of a harmonized 'cradle to grave' approach to managing sources consistent with international legal instruments, IAEA safety standards, and international good practices. This 'cradle to grave' approach requires the development of a national policy and implementing strategy, an adequate legal and regulatory framework, and adequate resources and infrastructure that cover the entire life cycle, from production and use of radioactive sources to disposal. (authors)

  5. Overview of Nevada Test Site Radioactive and Mixed Waste Disposal Operations

    SciTech Connect

    J.T. Carilli; S.K. Krenzien; R.G. Geisinger; S.J. Gordon; B. Quinn

    2009-03-01

    The U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Site Office Environmental Management Program is responsible for carrying out the disposal of on-site and off-site generated low-level radioactive waste (LLW) and low-level radioactive mixed waste (MW) at the Nevada Test Site (NTS). Core elements of this mission are ensuring safe and cost-effective disposal while protecting workers, the public, and the environment. This paper focuses on the impacts of new policies, processes, and opportunities at the NTS related to LLW and MW. Covered topics include: the first year of direct funding for NTS waste disposal operations; zero tolerance policy for non-compliant packages; the suspension of mixed waste disposal; waste acceptance changes; DOE Consolidated Audit Program (DOECAP) auditing; the 92-Acre Area closure plan; new eligibility requirements for generators; and operational successes with unusual waste streams.

  6. The adequacy of current import and export controls on sealed radioactive sources.

    SciTech Connect

    Longley, Susan W.; Cochran, John Russell; Price, Laura L.; Lipinski, Kendra J.

    2003-10-01

    Millions of sealed radioactive sources (SRSs) are being used for a wide variety of beneficial purposes throughout the world. Security experts are now concerned that these beneficial SRSs could be used in a radiological dispersion device to terrorize and disrupt society. The greatest safety and security threat is from those highly radioactive Category 1 and 2 SRSs. Without adequate controls, it may be relatively easy to legally purchase a Category 1 or 2 SRS on the international market under false pretenses. Additionally, during transfer, SRSs are particularly susceptible to theft since the sources are in a shielded and mobile configuration, transportation routes are predictable, and shipments may not be adequately guarded. To determine if government controls on SRS are adequate, this study was commissioned to review the current SRS import and export controls of six countries. Canada, the Russian Federation, and South Africa were selected as the exporting countries, and Egypt, the Philippines, and the United States were selected as importing countries. A detailed review of the controls in each country is presented. The authors found that Canada and Russia are major exporters, and are exporting highly radioactive SRSs without first determining if the recipient is authorized by the receiving country to own and use the SRSs. Available evidence was used to estimate that on average there are tens to possibly hundreds of intercountry transfers of highly radioactive SRSs each day. Based on these and other findings, this reports recommends stronger controls on the export and import of highly radioactive SRSs.

  7. Managing commercial low-level radioactive waste beyond 1992: Transportation planning for a LLW disposal facility

    SciTech Connect

    Quinn, G.J.

    1992-01-01

    This technical bulletin presents information on the many activities and issues related to transportation of low-level radioactive waste (LLW) to allow interested States to investigate further those subjects for which proactive preparation will facilitate the development and operation of a LLW disposal facility. The activities related to transportation for a LLW disposal facility are discussed under the following headings: safety; legislation, regulations, and implementation guidance; operations-related transport (LLW and non-LLW traffic); construction traffic; economics; and public involvement.

  8. Review of private sector treatment, storage, and disposal capacity for radioactive waste. Revision 1

    SciTech Connect

    Smith, M.; Harris, J.G.; Moore-Mayne, S.; Mayes, R.; Naretto, C.

    1995-04-14

    This report is an update of a report that summarized the current and near-term commercial and disposal of radioactive and mixed waste. This report was capacity for the treatment, storage, dating and written for the Idaho National Engineering Laboratory (INEL) with the objective of updating and expanding the report entitled ``Review of Private Sector Treatment, Storage, and Disposal Capacity for Radioactive Waste``, (INEL-95/0020, January 1995). The capacity to process radioactively-contaminated protective clothing and/or respirators was added to the list of private sector capabilities to be assessed. Of the 20 companies surveyed in the previous report, 14 responded to the request for additional information, five did not respond, and one asked to be deleted from the survey. One additional company was identified as being capable of performing LLMW treatability studies and six were identified as providers of laundering services for radioactively-contaminated protective clothing and/or respirators.

  9. Scenario for the safety assessment of near surface radioactive waste disposal in Serpong, Indonesia

    SciTech Connect

    Purnomo, A.S.

    2007-07-01

    Near surface disposal has been practiced for some decades, with a wide variation in sites, types and amounts of wastes, and facility designs employed. Experience has shown that the effective and safe isolation of waste depends on the performance of the overall disposal system, which is formed by three major components or barriers: the site, the disposal facility and the waste form. The objective of radioactive waste disposal is to isolate waste so that it does not result in undue radiation exposure to humans and the environment. In near surface disposal, the disposal facility is located on or below the ground surface, where the protective covering is generally a few meters thick. These facilities are intended to contain low and intermediate level waste without appreciable quantities of long-lived radionuclides. Safety is the most important aspect in the applications of nuclear technology and the implementation of nuclear activities in Indonesia. This aspect is reflected by a statement in the Act Number 10 Year 1997, that 'The Development and use of nuclear energy in Indonesia has to be carried out in such away to assure the safety and health of workers, the public and the protection of the environment'. Serpong are one of the sites for a nuclear research center facility, it is the biggest one in Indonesia. In the future will be developed the first near surface disposal on site of the nuclear research facility in Serpong. The paper will mainly focus on scenario of the safety assessments of near-surface radioactive waste disposal is often important to evaluate the performance of the disposal system (disposal facility, geosphere and biosphere). It will give detail, how at the present and future conditions, including anticipated and less probable events in order to prevent radionuclide migration to human and environment. Refer to the geology characteristic and ground water table is enable to place something Near Surface Disposal on unsaturated zone in Serpong site

  10. Ukranian program of radioactive waste disposal in geological formations

    SciTech Connect

    Khrushchov, D.P.; Pavlovsky, M.A.; Starodoumov, V.M.

    1996-12-01

    On the initiative of State Committee on Nuclear Power Utilization the purposeful investigations in the frames of interinstitutional program `isolation of radioactive waste in geologic formations` has been started in 1998. A preparatory stage of R&D program has been completed.

  11. Disposal of Radioactive Waste at Hanford Creates Problems

    ERIC Educational Resources Information Center

    Chemical and Engineering News, 1978

    1978-01-01

    Radioactive storage tanks at the Hanford facility have developed leaks. The situation is presently considered safe, but serious. A report from the National Academy of Science has recommended that the wastes be converted to stable solids and stored at another site on the Hanford Reservation. (Author/MA)

  12. Implications of recent ICRP recommendations for risk assessments for radioactive waste disposal and cleanup

    SciTech Connect

    Devgun, J.S.

    1992-01-01

    The International Commission on Radiological Protection (ICRP) adopted a new set of recommendations in November 1990 which were issued at ICRP Publication No. 60 in March 1991. These recommendations incorporate new radiobiological information and outline a comprehensive system of radiological protection. This paper evaluates the implications of these new recommendations vis a vis risk assessments for radioactive waste disposal and remediation of radioactively contaminated sites.

  13. Implications of recent ICRP recommendations for risk assessments for radioactive waste disposal and cleanup

    SciTech Connect

    Devgun, J.S.

    1992-04-01

    The International Commission on Radiological Protection (ICRP) adopted a new set of recommendations in November 1990 which were issued at ICRP Publication No. 60 in March 1991. These recommendations incorporate new radiobiological information and outline a comprehensive system of radiological protection. This paper evaluates the implications of these new recommendations vis a vis risk assessments for radioactive waste disposal and remediation of radioactively contaminated sites.

  14. Radiocarbon signal of a low and intermediate level radioactive waste disposal facility in nearby trees.

    PubMed

    Janovics, R; Kelemen, D I; Kern, Z; Kapitány, S; Veres, M; Jull, A J T; Molnár, M

    2016-03-01

    Tree ring series were collected from the vicinity of a Hungarian radioactive waste treatment and disposal facility and from a distant control background site, which is not influenced by the radiocarbon discharge of the disposal facility but it represents the natural regional (14)C level. The (14)C concentration of the cellulose content of tree rings was measured by AMS. Data of the tree ring series from the disposal facility was compared to the control site for each year. The results were also compared to the (14)C data of the atmospheric (14)C monitoring stations at the disposal facility and to international background measurements. On the basis of the results, the excess radiocarbon of the disposal facility can unambiguously be detected in the tree from the repository site. PMID:26704325

  15. The Current Status of Radioactive Waste Management and Planning for Near Surface Disposal in Indonesia

    SciTech Connect

    Purnomo, A. S.

    2003-02-24

    Near surface disposal has been practiced for some decades, with a wide variation in sites, types and amounts of wastes, and facility designs employed. Experience has shown that the effective and safe isolation of waste depends on the performance of the overall disposal system, which is formed by three major components or barriers: the site, the disposal facility and the waste form. Near surface disposal also rely on active institutional controls, such as monitoring and maintenance. The objective of radioactive waste disposal is to isolate waste so that it does not result in undue radiation exposure to humans and the environment. The required degree of isolation can be obtained by implementing various disposal methods, of which near surface disposal represents an option commonly used and demonstrated in several countries. In near surface disposal, the disposal facility is located on or below the ground surface, where the protective covering is generally a few meters thick. The se facilities are intended to contain low and intermediate level waste without appreciable quantities of long-lived radionuclides.

  16. Calculational technique to predict combustible gas generation in sealed radioactive waste containers

    SciTech Connect

    Flaherty, J.E.; Fujita, A.; Deltete, C.P.; Quinn, G.J.

    1986-05-01

    Certain forms of nuclear waste, when subjected to ionizing radiation, produce combustible mixtures of gases. The production of these gases in sealed radioactive waste containers represents a significant safety concern for the handling, shipment and storage of waste. The US Nuclear Regulatory Commission (NRC) acted on this safety concern in September 1984 by publishing an information notice requiring waste generators to demonstrate, by tests or measurements, that combustible mixtures of gases are not present in radioactive waste shipments; otherwise the waste must be vented within 10 days of shipping. A task force, formed by the Edison Electric Institute to evaluate these NRC requirements, developed a calculational method to quantify hydrogen gas generation in sealed containers. This report presents the calculational method along with comparisons to actual measured hydrogen concentrations from EPICOR II liners, vented during their preparation for shipment. As a result of this, the NRC recently altered certain waste shipment Certificates-Of-Compliance to allow calculations, as well as tests and measurements, as acceptable means of determining combustible gas concentration. This modification was due in part to work described herein.

  17. 10 CFR 51.62 - Environmental report-land disposal of radioactive waste licensed under 10 CFR part 61.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ....62 Environmental report—land disposal of radioactive waste licensed under 10 CFR part 61. (a) Each... 10 Energy 2 2013-01-01 2013-01-01 false Environmental report-land disposal of radioactive waste licensed under 10 CFR part 61. 51.62 Section 51.62 Energy NUCLEAR REGULATORY COMMISSION...

  18. 10 CFR 51.62 - Environmental report-land disposal of radioactive waste licensed under 10 CFR part 61.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ....62 Environmental report—land disposal of radioactive waste licensed under 10 CFR part 61. (a) Each... 10 Energy 2 2012-01-01 2012-01-01 false Environmental report-land disposal of radioactive waste licensed under 10 CFR part 61. 51.62 Section 51.62 Energy NUCLEAR REGULATORY COMMISSION...

  19. 10 CFR 51.62 - Environmental report-land disposal of radioactive waste licensed under 10 CFR part 61.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ....62 Environmental report—land disposal of radioactive waste licensed under 10 CFR part 61. (a) Each... 10 Energy 2 2011-01-01 2011-01-01 false Environmental report-land disposal of radioactive waste licensed under 10 CFR part 61. 51.62 Section 51.62 Energy NUCLEAR REGULATORY COMMISSION...

  20. 10 CFR 51.62 - Environmental report-land disposal of radioactive waste licensed under 10 CFR part 61.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ....62 Environmental report—land disposal of radioactive waste licensed under 10 CFR part 61. (a) Each... 10 Energy 2 2014-01-01 2014-01-01 false Environmental report-land disposal of radioactive waste licensed under 10 CFR part 61. 51.62 Section 51.62 Energy NUCLEAR REGULATORY COMMISSION...

  1. 10 CFR 51.62 - Environmental report-land disposal of radioactive waste licensed under 10 CFR part 61.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ....62 Environmental report—land disposal of radioactive waste licensed under 10 CFR part 61. (a) Each... 10 Energy 2 2010-01-01 2010-01-01 false Environmental report-land disposal of radioactive waste licensed under 10 CFR part 61. 51.62 Section 51.62 Energy NUCLEAR REGULATORY COMMISSION...

  2. Feasibility of space disposal of radioactive nuclear waste. 2: Technical summary

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The feasibility of transporting radioactive waste produced in the process of generating electricity in nuclear powerplants into space for ultimate disposal was investigated at the request of the AEC as a NASA in-house effort. The investigation is part of a broad AEC study of methods for long-term storage or disposal of radioactive waste. The results of the study indicate that transporting specific radioactive wastes, particularly the actinides with very long half-lives, into space using the space shuttle/tug as the launch system, appears feasible from the engineering and safety viewpoints. The space transportation costs for ejecting the actinides out of the solar system would represent less than a 5-percent increase in the average consumer's electric bill.

  3. Managing suspect radioactive material in the DOE system -- A program to establish lower activity disposal criteria

    SciTech Connect

    Pollard, C.G.; Shuman, R.; Rogers, V.

    1994-12-31

    Operations at Department of Energy (DOE) nuclear installations routinely generate radioactively contaminated waste. A large portion of this waste has extremely low levels of radioactive contamination or is suspect waste. Despite these very low levels of contamination, this waste is disposed of as low-level radioactive waste (LLW) or mixed waste. Doing so depleted limited available disposal capacity while providing little or no incremental benefit to the public health and safety. Efforts have been made by federal agencies, states, and industry to establish less rigorous control criteria for waste with low levels of radioactive contamination. The DOE addressed the establishment of lower activity disposal criteria in its threshold limit guidance in the early 1980s, but, to date, nor formal limits have emerged from the Department. A number of DOE installation have calculated suitable site-specific release limits. Efforts by other federal agencies range from proposed dose criteria for Below Regulatory Concern (BRC) waste developed by the U.S. Environmental Protection Agency (EPA) to policy statements by the U.S. Nuclear Regulatory Commission (NRC) on BRC waste which were subsequently withdrawn. Such limits may be developed incrementally, focusing first on waste streams that are easily characterized and that will provide the greatest immediate benefit to the DOE system. Limits may then be developed for waste streams containing more complex mixtures of radionuclides. Separate limits may be developed for each DOE site, taking into account the site-specific disposal conditions, or a single set of limits may be developed for the entire DOE system. Once lower activity disposal limits are established, DOE installations will need to develop waste characterization methods adequate to ensure compliance with the new lower activity disposal criteria.

  4. Treatment of uncertainties in the geologic disposal of radioactive waste

    SciTech Connect

    Cranwell, R.M.

    1985-12-31

    Uncertainty in the analysis of geologic waste disposal is generally considered to have three primary components: (1) computer code/model uncertainty, (2) model parameter uncertainty, and (3) scenario uncertainty. Computer code/model uncertainty arises from problems associated with determination of appropriate parameters for use in model construction, mathematical formulatin of models, and numerical techniques used in conjunction with the mathematical formulation of models. Model parameter uncertainty arises from problems associated with selection of appropriate values for model input, data interpretation and possible misuse of data, and variation of data. Scenario uncertainty arises from problems associated with the "completeness` of scenarios, the definition of parameters which describe scenarios, and the rate or probability of scenario occurrence. The preceding sources of uncertainty are discussed below.

  5. U.S. Geological Survey research in radioactive waste disposal; fiscal year 1980

    USGS Publications Warehouse

    Schneider, Robert; Trask, N.J.

    1982-01-01

    The report summarizes progress on geologic and hydrologic research related to the disposal of radioactive wastes. The research is described according to whether it is related most directly to: (1) High-level and transuranic wastes; (2) Low-level wastes, or (3) Uranium mill tailings. Included is research applicable to the identification and geohydrologic characterization of waste-disposal sites, to investigations of specific sites where wastes have been stored, and to studies of regions or environments where waste-disposal sites might be located. A significant part of the activity is concerned with techniques and methods for characterizing disposal sites and studies of geologic and hydrologic processes related to the transport and (or) retention of waste radionuclides.

  6. Impact of microbial activity on the radioactive waste disposal: long term prediction of biocorrosion processes.

    PubMed

    Libert, Marie; Schütz, Marta Kerber; Esnault, Loïc; Féron, Damien; Bildstein, Olivier

    2014-06-01

    This study emphasizes different experimental approaches and provides perspectives to apprehend biocorrosion phenomena in the specific disposal environment by investigating microbial activity with regard to the modification of corrosion rate, which in turn can have an impact on the safety of radioactive waste geological disposal. It is found that iron-reducing bacteria are able to use corrosion products such as iron oxides and "dihydrogen" as new energy sources, especially in the disposal environment which contains low amounts of organic matter. Moreover, in the case of sulphate-reducing bacteria, the results show that mixed aerobic and anaerobic conditions are the most hazardous for stainless steel materials, a situation which is likely to occur in the early stage of a geological disposal. Finally, an integrated methodological approach is applied to validate the understanding of the complex processes and to design experiments aiming at the acquisition of kinetic data used in long term predictive modelling of biocorrosion processes. PMID:24177136

  7. Performance assessment monitoring of low-level radioactive waste disposal facilities

    SciTech Connect

    Garland, S.B. II; Craig, P.M.; Styers, D.R.

    1988-01-01

    To develop a long-range plan for the disposal of the solid low-level radioactive wastes (LLW) generated by these facilities, the Low-Level Waste Disposal Development and Demonstration Program was initiated. A key component of the program is selecting promising disposal technologies to be demonstrated at a scale sufficient to assess performance adequately. One technology selected for demonstration is the aboveground tumulus. The tumulus facility consists of a concrete pad on which the LLW is placed, a synthetic underpad liner, concrete disposal vaults in which the LLW is contained, and a multilayered cap to be constructed after the pad is filled. This paper describes the methodology being used to assess the performance of the tumulus in terms of environmental impacts and worker exposures. This assessment also will assist in determining monitoring needs during routine operations of future full-scale facilities.

  8. Assessment of a radioactive waste disposal site at Enewetak Atoll.

    PubMed

    Noshkin, V E; Robison, W L

    1997-07-01

    The 43 nuclear tests conducted at Enewetak Atoll by the United States between 1948 and 1958 produced close-in fallout that contaminated the islands and lagoon of the atoll with radioactive fission and activation products, and unfissioned nuclear fuel. In 1972, the U.S. government announced that it would conduct a cleanup and restoration operation to return the atoll to the Enewetak people. The radiological cleanup began in 1977 and lasted to 1980 and focused on reducing the concentration of the transuranium elements (238,239,240Pu and 241Am = TRU) in soils on some of the islands that might eventually be used for residence or for subsistence agricultural. The cleanup plan called for relocating soil and some other contaminated debris to Runit Island on the eastern perimeter of the Atoll. Some of the contaminated soil was mixed with cement and the mixture placed below the water level in the Cactus Crater that was formed by a nuclear explosion in 1958. The remainder of the contaminated material was mixed with concrete and placed above ground over the crater in the shape of a dome. A concrete cap was constructed over the dome of soil. Concern has been expressed by the people of Enewetak and by others over the possible aquatic impacts from the radionuclides entombed in the crater. A National Academy of Sciences committee examined the dome and concluded that the containment structure and its contents present no credible health hazard to the people of Enewetak, either now or in the future. The committee suggested that "at least part of the radioactivity contained in the structure is available for transport to the groundwater and subsequently to the lagoon and it is important to determine whether this pathway may be a significant one." Therefore, a surveillance program was started in 1980, in conjunction with other research efforts, to study the radionuclides in samples of fish, groundwater, and lagoon seawater. Our data and conclusions support the findings suggested by the

  9. Numerical Model of Fluid Flow through Heterogeneous Rock for High Level Radioactive Waste Disposal

    NASA Astrophysics Data System (ADS)

    Shirai, M.; Chiba, R.; Fomin, S.; Chugunov, V.; Takahashi, T.; Niibori, Y.; Hashida, T.

    2007-03-01

    An international consensus has emerged that deep geological disposal on land is one of the most appropriate means for high level radioactive wastes (HLW). The fluid transport is slow and radioactive elements are dangerous, so it's impossible to experiment over thousands of years. Instead, numerical model in such natural barrier as fractured underground needs to be considered. Field observations reveal that the equation with fractional derivative is more appropriate for describing physical phenomena than the equation which is based on the Fick's law. Thus, non-Fickian diffusion into inhomogeneous underground appears to be important in the assessment of HLW disposal. A solute transport equation with fractional derivative has been suggested and discussed in literature. However, no attempts were made to apply this equation for modeling of HLW disposal with account for the radioactive decay. In this study, we suggest the use of a novel fractional advection-diffusion equation which accounts for the effect of radioactive disintegration and for interactions between major, macro pores and fractal micro pores. This model is fundamentally different from previous proposed model of HLW, particularly in utilizing fractional derivative. Breakthrough curves numerically obtained by the present model are presented for a variety of rock types with respect to some important nuclides. Results of the calculation showed that for longer distance our model tends to be more conservative than the conventional Fickian model, therefore our model can be said to be safer.

  10. Numerical Model of Fluid Flow through Heterogeneous Rock for High Level Radioactive Waste Disposal

    SciTech Connect

    Shirai, M.; Chiba, R.; Takahashi, T.; Hashida, T.; Fomin, S.; Chugunov, V.; Niibori, Y.

    2007-03-20

    An international consensus has emerged that deep geological disposal on land is one of the most appropriate means for high level radioactive wastes (HLW). The fluid transport is slow and radioactive elements are dangerous, so it's impossible to experiment over thousands of years. Instead, numerical model in such natural barrier as fractured underground needs to be considered. Field observations reveal that the equation with fractional derivative is more appropriate for describing physical phenomena than the equation which is based on the Fick's law. Thus, non-Fickian diffusion into inhomogeneous underground appears to be important in the assessment of HLW disposal. A solute transport equation with fractional derivative has been suggested and discussed in literature. However, no attempts were made to apply this equation for modeling of HLW disposal with account for the radioactive decay. In this study, we suggest the use of a novel fractional advection-diffusion equation which accounts for the effect of radioactive disintegration and for interactions between major, macro pores and fractal micro pores. This model is fundamentally different from previous proposed model of HLW, particularly in utilizing fractional derivative. Breakthrough curves numerically obtained by the present model are presented for a variety of rock types with respect to some important nuclides. Results of the calculation showed that for longer distance our model tends to be more conservative than the conventional Fickian model, therefore our model can be said to be safer.

  11. Taiwan industrial cooperation program technology transfer for low-level radioactive waste final disposal - phase I.

    SciTech Connect

    Knowlton, Robert G.; Cochran, John Russell; Arnold, Bill Walter; Jow, Hong-Nian; Mattie, Patrick D.; Schelling, Frank Joseph Jr.

    2007-01-01

    Sandia National Laboratories and the Institute of Nuclear Energy Research, Taiwan have collaborated in a technology transfer program related to low-level radioactive waste (LLW) disposal in Taiwan. Phase I of this program included regulatory analysis of LLW final disposal, development of LLW disposal performance assessment capabilities, and preliminary performance assessments of two potential disposal sites. Performance objectives were based on regulations in Taiwan and comparisons to those in the United States. Probabilistic performance assessment models were constructed based on limited site data using software including GoldSim, BLT-MS, FEHM, and HELP. These software codes provided the probabilistic framework, container degradation, waste-form leaching, groundwater flow, radionuclide transport, and cover infiltration simulation capabilities in the performance assessment. Preliminary performance assessment analyses were conducted for a near-surface disposal system and a mined cavern disposal system at two representative sites in Taiwan. Results of example calculations indicate peak simulated concentrations to a receptor within a few hundred years of LLW disposal, primarily from highly soluble, non-sorbing radionuclides.

  12. Ecological characteristics of small mammals on a radioactive waste disposal area in southeastern Idaho

    SciTech Connect

    Groves, C.R.; Keller, B.L.

    1983-01-01

    Species composition, diversity, biomass and densities of small mammal populations were examined in crested wheatgrass (Agropyron cristatum) and Russian thistle (Salsola kali) habitats on a solid radioactive waste disposal area and in native sagebrush (Artemisia tridentala) habitat surrounding the disposal area. The 15-month live-trapping study resulted in the marketing of 2384 individuals representing 10 species of small mammals. The deer mouse (Peromyscus maniculatus) was the most common rodent in both disposal area habitats and the adjacent sagebrush habitat; Ord's kangaroo rat (Dipodomys ordii) was also an abundant rodent in all vegetation types. The montane vole (Microtus montanus) was common only in crested wheatgrass stands on the disposal area. Although the adjacent native sagebrush habitat had the highest species diversity and the Russian thistle habitat on the disposal area had the lowest, the total rodent density was not significantly different among the three vegetation types. Crested wheatgrass within the disposal area contained the largest rodent biomass throughout the study, in part due to an increasing M. montanus population. The peak small mammal biomass of 5000 g/ha in creasted wheatgrass and sagebrush habitats was considerably higher than previously reported for similar habitats. Differences in diversity and biomass between the disposal area and surrounding native habitat are most likely related to differences in soil compaction and vegetation between these two areas.

  13. PROBABILISTIC RISK ANALYSIS OF RADIOACTIVE WASTE DISPOSALS - a case study

    NASA Astrophysics Data System (ADS)

    Trinchero, P.; Delos, A.; Tartakovsky, D. M.; Fernandez-Garcia, D.; Bolster, D.; Dentz, M.; Sanchez-Vila, X.; Molinero, J.

    2009-12-01

    The storage of contaminant material in superficial or sub-superficial repositories, such as tailing piles for mine waste or disposal sites for low and intermediate nuclear waste, poses a potential threat for the surrounding biosphere. The minimization of these risks can be achieved by supporting decision-makers with quantitative tools capable to incorporate all source of uncertainty within a rigorous probabilistic framework. A case study is presented where we assess the risks associated to the superficial storage of hazardous waste close to a populated area. The intrinsic complexity of the problem, involving many events with different spatial and time scales and many uncertainty parameters is overcome by using a formal PRA (probabilistic risk assessment) procedure that allows decomposing the system into a number of key events. Hence, the failure of the system is directly linked to the potential contamination of one of the three main receptors: the underlying karst aquifer, a superficial stream that flows near the storage piles and a protection area surrounding a number of wells used for water supply. The minimal cut sets leading to the failure of the system are obtained by defining a fault-tree that incorporates different events including the failure of the engineered system (e.g. cover of the piles) and the failure of the geological barrier (e.g. clay layer that separates the bottom of the pile from the karst formation). Finally the probability of failure is quantitatively assessed combining individual independent or conditional probabilities that are computed numerically or borrowed from reliability database.

  14. Assessment of a radioactive waste disposal site at Enewetak Atoll

    SciTech Connect

    Noshkin, V.E.; Robison, W.L.

    1997-07-01

    The 43 nuclear tests conducted at Enewetak Atoll by the United States between 1948 and 1958 produced close-in fallout that contaminated the islands and lagoon of the atoll with radioactive fission and activation products, and unfissioned nuclear fuel. In 1972, the U.S. government announced that it would conduct a cleanup and restoration operation to return the atoll to the Enewetak people. The radiological cleanup began in 1977 and lasted to 1980 and focused on reducing the concentration of the transuranium elements ({sup 238,239,240}Pu and {sup 241}Am = TRU) in soils on some of the islands that might eventually be used for residence or for subsistence agricultural. The cleanup plan called for relocating soil and some other contaminated debris to Runit Island on the eastern perimeter of the Atoll. Some of the contaminated soil was mixed with cement and the mixture placed below the water level in the Cactus Crater that was formed by a nuclear explosion in 1958. The remainder of the contaminated material was mixed with concrete and placed above ground over the crater in the shape of a dome. A concrete cap was constructed over the dome of soil. Concern has been expressed by the people of Enewetak and by others over the possible aquatic impacts from the radionuclides entombed in the crater. Therefore, a surveillance program was started in 1980, in conjunction with other research efforts, to study the radionuclides in samples of fish, groundwater, and lagoon seawater. Our data and conclusions support the findings suggested by the National Academy committee over a decade ago in that any assumption of rapid remobilization of all or any of the dome`s transuranics or other radionuclides is an extreme one. 22 refs., 4 figs., 10 tabs.

  15. SIMPLIFIED PRACTICAL TEST METHOD FOR PORTABLE DOSE METERS USING SEVERAL SEALED RADIOACTIVE SOURCES.

    PubMed

    Mikamoto, Takahiro; Yamada, Takahiro; Kurosawa, Tadahiro

    2016-09-01

    Sealed radioactive sources which have small activity were employed for the determination of response and tests for non-linearity and energy dependence of detector responses. Close source-to-detector geometry (at 0.3 m or less) was employed to practical tests for portable dose meters to accumulate statistically sufficient ionizing currents. Difference between response in the present experimentally studied field and in the reference field complied with ISO 4037 due to non-uniformity of radiation fluence at close geometry was corrected by use of Monte Carlo simulation. As a consequence, corrected results were consistent with the results obtained in the ISO 4037 reference field within their uncertainties. PMID:27521204

  16. Performance assessment overview for subseabed disposal of high level radioactive waste

    SciTech Connect

    Klett, R.D.

    1997-06-01

    The Subseabed Disposal Project (SDP) was part of an international program that investigated the feasibility of high-level radioactive waste disposal in the deep ocean sediments. This report briefly describes the seven-step iterative performance assessment procedures used in this study and presents representative results of the last iteration. The results of the performance are compared to interim standards developed for the SDP, to other conceptual repositories, and to related metrics. The attributes, limitations, uncertainties, and remaining tasks in the SDP feasibility phase are discussed.

  17. Application of total uncertainty theory in radioactive waste disposal facilities safety assessment

    SciTech Connect

    Lemos, Francisco Luiz de; Ross, Timothy; Sullivan, Terry

    2007-07-01

    Safety assessment requires the interaction of a large number of disciplines to model the environmental phenomena necessary to evaluate the safety of the disposal system. In this complex process, the identification and quantification of both types of uncertainties, random and epistemic, plays a very important role for confidence building. In this work an application of the concept of total uncertainty to radioactive waste disposal facilities safety assessment is proposed. By combining both types of uncertainty, aleatory and epistemic, in the same framework, this approach ultimately aims to assess the confidence one can pose in the safety-assessment decisions. (authors)

  18. Cost-benefit of final radiological survey versus radioactive waste disposal.

    PubMed

    Barroso, Jeff; Roberts, Sarah

    2003-02-01

    A significant portion of the cost for D&D is related to low-level waste disposal, decontamination, and final radiological survey. For that reason, a careful cost-benefit analysis must be performed weighing the cost of decontaminating and radiologically surveying the building media for release against the cost of disposing of the material as radioactive waste. This cost-benefit analysis visibly came into play at the Rocky Flats Environmental Technology Site during the recent D&D of two facilities. PMID:12564340

  19. Cost-Benefit of Final Radiological Survey Versus Radioactive Waste Disposal.

    PubMed

    Barroso, Jeff; Roberts, Sarah

    2003-02-01

    ABSTRACT A significant portion of the cost for D&D is related to low-level waste disposal, decontamination, and final radiological survey. For that reason, a careful cost-benefit analysis must be performed weighing the cost of decontaminating and radiologically surveying the building media for release against the cost of disposing of the material as radioactive waste. This cost-benefit analysis visibly came into play at the Rocky Flats Environmental Technology Site during the recent D&D of two facilities. PMID:12555030

  20. Social and institutional evaluation report for Greater-Than-Class C Low-Level Radioactive Waste Disposal

    SciTech Connect

    Anderson, T.L.; Lewis, B.E.; Turner, K.H.; Rozelle, M.A.

    1993-10-01

    This report identifies and characterizes social and institutional issues that would be relevant to the siting, licensing, construction, closure, and postclosure of a Greater-Than-Class-C low-level radioactive waste (GTCC LLW) disposal facility. A historical perspective of high-level radioactive waste (HLW) and LLW disposal programs is provided as an overview of radioactive waste disposal and to support the recommendations and conclusions in the report. A characterization of each issue is provided to establish the basis for further evaluations. Where applicable, the regulatory requirements of 10 CFR 60 and 61 are incorporated in the issue characterizations. The issues are used to compare surface, intermediate depth, and deep geologic disposal alternatives. The evaluation establishes that social and institutional issues do not significantly discriminate among the disposal alternatives. Recommendations are provided for methods by which the issues could be considered throughout the lifecycle of a GTCC LLW disposal program.

  1. MANAGING UNCERTAINTIES ASSOCIATED WITH RADIOACTIVE WASTE DISPOSAL: TASK GROUP 4 OF THE IAEA PRISM PROJECT

    SciTech Connect

    Seitz, R.

    2011-03-02

    It is widely recognized that the results of safety assessment calculations provide an important contribution to the safety arguments for a disposal facility, but cannot in themselves adequately demonstrate the safety of the disposal system. The safety assessment and a broader range of arguments and activities need to be considered holistically to justify radioactive waste disposal at any particular site. Many programs are therefore moving towards the production of what has become known as a Safety Case, which includes all of the different activities that are conducted to demonstrate the safety of a disposal concept. Recognizing the growing interest in the concept of a Safety Case, the International Atomic Energy Agency (IAEA) is undertaking an intercomparison and harmonization project called PRISM (Practical Illustration and use of the Safety Case Concept in the Management of Near-surface Disposal). The PRISM project is organized into four Task Groups that address key aspects of the Safety Case concept: Task Group 1 - Understanding the Safety Case; Task Group 2 - Disposal facility design; Task Group 3 - Managing waste acceptance; and Task Group 4 - Managing uncertainty. This paper addresses the work of Task Group 4, which is investigating approaches for managing the uncertainties associated with near-surface disposal of radioactive waste and their consideration in the context of the Safety Case. Emphasis is placed on identifying a wide variety of approaches that can and have been used to manage different types of uncertainties, especially non-quantitative approaches that have not received as much attention in previous IAEA projects. This paper includes discussions of the current results of work on the task on managing uncertainty, including: the different circumstances being considered, the sources/types of uncertainties being addressed and some initial proposals for approaches that can be used to manage different types of uncertainties.

  2. Unrestricted disposal of minimal activity levels of radioactive wastes: exposure and risk calculations

    SciTech Connect

    Fields, D.E.; Emerson, C.J.

    1984-08-01

    The US Nuclear Regulatory Commission is currently considering revision of rule 10 CFR Part 20, which covers disposal of solid wastes containing minimal radioactivity. In support of these revised rules, we have evaluated the consequences of disposing of four waste streams at four types of disposal areas located in three different geographic regions. Consequences are expressed in terms of human exposures and associated health effects. Each geographic region has its own climate and geology. Example waste streams, waste disposal methods, and geographic regions chosen for this study are clearly specified. Monetary consequences of minimal activity waste disposal are briefly discussed. The PRESTO methodology was used to evaluate radionuclide transport and health effects. This methodology was developed to assess radiological impacts to a static local population for a 1000-year period following disposal. Pathways and processes of transit from the trench to exposed populations included the following considerations: groundwater transport, overland flow, erosion, surface water dilution, resuspension, atmospheric transport, deposition, inhalation, and ingestion of contaminated beef, milk, crops, and water. 12 references, 2 figures, 8 tables.

  3. Geological Disposal of Radioactive Waste: A Long-Term Socio-Technical Experiment.

    PubMed

    Schröder, Jantine

    2016-06-01

    In this article we investigate whether long-term radioactive waste management by means of geological disposal can be understood as a social experiment. Geological disposal is a rather particular technology in the way it deals with the analytical and ethical complexities implied by the idea of technological innovation as social experimentation, because it is presented as a technology that ultimately functions without human involvement. We argue that, even when the long term function of the 'social' is foreseen to be restricted to safeguarding the functioning of the 'technical', geological disposal is still a social experiment. In order to better understand this argument and explore how it could be addressed, we elaborate the idea of social experimentation with the notion of co-production and the analytical tools of delegation, prescription and network as developed by actor-network theory. In doing so we emphasize that geological disposal inherently involves relations between surface and subsurface, between humans and nonhumans, between the social, material and natural realm, and that these relations require recognition and further elaboration. In other words, we argue that geological disposal concurrently is a social and a technical experiment, or better, a long-term socio-technical experiment. We end with proposing the idea of 'actor-networking' as a sensitizing concept for future research into what geological disposal as a socio-technical experiment could look like. PMID:25981511

  4. Equity of commercial low-level radioactive waste disposal fees. Report to Congress

    SciTech Connect

    1998-02-01

    In the Report accompanying the Fiscal Year 1997 Senate Energy and Water Development Appropriations Bill, the Senate Appropriations Committee directed the Department of Energy (DOE) to prepare a study of the costs of operating a low-level radioactive waste (LLW) disposal facility such as the one at Barnwell, South Carolina, and to determine whether LLW generators are paying equitable disposal fees. The disposal costs of four facilities are reviewed in this report, two operating facilities and two planned facilities. The operating facilities are located at Barnwell, South Carolina, and Richland, Washington. They are operated by Chem-Nuclear, LLC, (Chem-Nuclear), and US Ecology, Inc., (US Ecology), respectively. The planned facilities are expected to be built at Ward Valley, California, and Sierra Blanca, Texas. They will be operated by US Ecology and the State of Texas, respectively. This report found that disposal fees vary significantly among facilities for a variety of reasons. However, the information suggests that at each disposal facility, LLW generators pay equitable disposal fees.

  5. Recommended Procedures for Measuring Radon Fluxes from Disposal Sites of Residual Radioactive Materials

    SciTech Connect

    Young, J. A.; Thomas, V. W.; Jackson, P. O.

    1983-03-01

    This report recommends instrumentation and methods suitable for measuring radon fluxes emanating from covered disposal sites of residual radioactive materials such as uranium mill tailings. Problems of spatial and temporal variations in radon flux are discussed and the advantages and disadvantages of several instruments are examined. A year-long measurement program and a two month measurement methodology are then presented based on the inherent difficulties of measuring average radon flux over a cover using the recommended instrumentation.

  6. Marine disposal of radioactive wastes. (Latest citations from the NTIS bibliographic database). Published Search

    SciTech Connect

    1995-11-01

    The bibliography contains citations concerning radioactive waste disposal in seas, oceans, and coastal regions. Models, standards and regulations, government policy, and evaluations are covered. High-level and low-level nuclear wastes from nuclear power plants and ship propulsion reactors are discussed. References cover radionuclide migration, environmental exposure pathway, ecosystems, radiation dosages, carcinogens and neoplasms, and the effects on food chains. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  7. Radioactive sealed sources: Reasonable accountability, exemption, and licensing activity thresholds -- A technical basis

    SciTech Connect

    Lee, D.W.; Shingleton, K.L.

    1996-07-01

    Perhaps owing to their small size and portability, some radiation accidents/incidents have involved radioactive sealed sources (RSSs). As a result, programs for the control and accountability of RSSs have come to be recommended and emplaced that essentially require RSSs to be controlled in a manner different from bulk, unsealed radioactive material. Crucially determining the total number of RSSs for which manpower-intensive radiation protection surveillance is provided is the individual RSS activity above which such surveillance is required and below which such effort is not considered cost effective. Individual RSS activity thresholds are typically determined through scenarios which impart a chosen internal or external limiting dose to Reference Man under specified exposure conditions. The resultant RSS threshold activity levels have meaning commensurate with the assumed scenario exposure parameters, i.e., if they are realistic and technically based. A review of how the Department of Energy (DOE), the International Atomic Energy Agency (IAEA), and the Nuclear Regulatory Commission (NRC) have determined their respective accountability, exemption, and licensing threshold activity values is provided. Finally, a fully explained method using references readily available to practicing health physicists is developed using realistic, technically-based calculation parameters by which RSS threshold activities may be locally generated.

  8. The cleanup of releases of radioactive materials from commercial low-level radioactive waste disposal sites: Whose jurisdiction?

    SciTech Connect

    Hartnett, C.

    1994-12-31

    There exists an overlap between the Comprehensive Environmental Response, Compensation and Recovery Act ({open_quotes}CERCLA{close_quotes}) and the Atomic Energy Act ({open_quotes}AEA{close_quotes}) regarding the cleanup of releases of radioactive materials from commercial low-level radioactive waste sites. The Nuclear Regulatory Commission ({open_quotes}NRC{close_quotes}) and Agreement States have jurisdiction under the AEA, and the Environmental Protection Agency ({open_quotes}EPA{close_quotes}) has jurisdiction pursuant to CERCLA. This overlapping jurisdiction has the effect of imposing CERCLA liability on parties who have complied with AEA regulations. However, CERCLA was not intended to preempt existing legislation. This is evidenced by the federally permitted release exemption, which explicitly exempts releases from CERCLA liability pursuant to an AEA license. With little guidance as to the applicability of this exemption, it is uncertain whether CERCLA`s liability is broad enough to supersede the Atomic Energy Act. It is the purpose of this paper to discuss the overlapping jurisdiction for the cleanup of releases of radioactive materials from commercial low-level radioactive waste disposal sites with particular emphasis on the cleanup at the Maxey Flats, West Valley and Sheffield sites.

  9. Polonium-210 in the environment around a radioactive waste disposal area and phosphate ore processing plant.

    PubMed

    Arthur, W J; Markham, O D

    1984-04-01

    Polonium-210 concentrations were determined for soil, vegetation and small mammal tissues collected at a solid radioactive waste disposal area, near a phosphate ore processing plant and at two rural areas in southeastern Idaho. Polonium concentrations in media sampled near the radioactive waste disposal facility were equal to or less than values from rural area samples, indicating that disposal of solid radioactive waste at the Idaho National Engineering Laboratory Site has not resulted in increased environmental levels of polonium. Concentrations of 210Po in soils, deer mice hide and carcass samples collected near the phosphate processing plant were statistically (P less than or equal to 0.05) greater than the other sampling locations; however, the mean 210Po concentration in soils and small mammal tissues from sampling areas near the phosphate plant were only four and three times greater, respectively, than control values. No statistical (P greater than 0.05) difference was observed for 210Po concentrations in vegetation among any of the sampling locations. PMID:6706588

  10. Biodegradation of the Alkaline Cellulose Degradation Products Generated during Radioactive Waste Disposal

    PubMed Central

    Rout, Simon P.; Radford, Jessica; Laws, Andrew P.; Sweeney, Francis; Elmekawy, Ahmed; Gillie, Lisa J.; Humphreys, Paul N.

    2014-01-01

    The anoxic, alkaline hydrolysis of cellulosic materials generates a range of cellulose degradation products (CDP) including α and β forms of isosaccharinic acid (ISA) and is expected to occur in radioactive waste disposal sites receiving intermediate level radioactive wastes. The generation of ISA's is of particular relevance to the disposal of these wastes since they are able to form complexes with radioelements such as Pu enhancing their migration. This study demonstrates that microbial communities present in near-surface anoxic sediments are able to degrade CDP including both forms of ISA via iron reduction, sulphate reduction and methanogenesis, without any prior exposure to these substrates. No significant difference (n = 6, p = 0.118) in α and β ISA degradation rates were seen under either iron reducing, sulphate reducing or methanogenic conditions, giving an overall mean degradation rate of 4.7×10−2 hr−1 (SE±2.9×10−3). These results suggest that a radioactive waste disposal site is likely to be colonised by organisms able to degrade CDP and associated ISA's during the construction and operational phase of the facility. PMID:25268118

  11. Bacterial Diversity in Bentonites, Engineered Barrier for Deep Geological Disposal of Radioactive Wastes.

    PubMed

    Lopez-Fernandez, Margarita; Cherkouk, Andrea; Vilchez-Vargas, Ramiro; Jauregui, Ruy; Pieper, Dietmar; Boon, Nico; Sanchez-Castro, Ivan; Merroun, Mohamed L

    2015-11-01

    The long-term disposal of radioactive wastes in a deep geological repository is the accepted international solution for the treatment and management of these special residues. The microbial community of the selected host rocks and engineered barriers for the deep geological repository may affect the performance and the safety of the radioactive waste disposal. In this work, the bacterial population of bentonite formations of Almeria (Spain), selected as a reference material for bentonite-engineered barriers in the disposal of radioactive wastes, was studied. 16S ribosomal RNA (rRNA) gene-based approaches were used to study the bacterial community of the bentonite samples by traditional clone libraries and Illumina sequencing. Using both techniques, the bacterial diversity analysis revealed similar results, with phylotypes belonging to 14 different bacterial phyla: Acidobacteria, Actinobacteria, Armatimonadetes, Bacteroidetes, Chloroflexi, Cyanobacteria, Deinococcus-Thermus, Firmicutes, Gemmatimonadetes, Planctomycetes, Proteobacteria, Nitrospirae, Verrucomicrobia and an unknown phylum. The dominant groups of the community were represented by Proteobacteria and Bacteroidetes. A high diversity was found in three of the studied samples. However, two samples were less diverse and dominated by Betaproteobacteria. PMID:26024740

  12. Biodegradation of the alkaline cellulose degradation products generated during radioactive waste disposal.

    PubMed

    Rout, Simon P; Radford, Jessica; Laws, Andrew P; Sweeney, Francis; Elmekawy, Ahmed; Gillie, Lisa J; Humphreys, Paul N

    2014-01-01

    The anoxic, alkaline hydrolysis of cellulosic materials generates a range of cellulose degradation products (CDP) including α and β forms of isosaccharinic acid (ISA) and is expected to occur in radioactive waste disposal sites receiving intermediate level radioactive wastes. The generation of ISA's is of particular relevance to the disposal of these wastes since they are able to form complexes with radioelements such as Pu enhancing their migration. This study demonstrates that microbial communities present in near-surface anoxic sediments are able to degrade CDP including both forms of ISA via iron reduction, sulphate reduction and methanogenesis, without any prior exposure to these substrates. No significant difference (n = 6, p = 0.118) in α and β ISA degradation rates were seen under either iron reducing, sulphate reducing or methanogenic conditions, giving an overall mean degradation rate of 4.7 × 10(-2) hr(-1) (SE ± 2.9 × 10(-3)). These results suggest that a radioactive waste disposal site is likely to be colonised by organisms able to degrade CDP and associated ISA's during the construction and operational phase of the facility. PMID:25268118

  13. DRINK: a biogeochemical source term model for low level radioactive waste disposal sites.

    PubMed

    Humphreys, P; McGarry, R; Hoffmann, A; Binks, P

    1997-07-01

    Interactions between element chemistry and the ambient geochemistry play a significant role in the control of radionuclide migration in the geosphere. These same interactions influence radionuclide release from near surface, low level radioactive waste, disposal sites once physical containment has degraded. In situations where LLW contains significant amounts of metal and organic materials such as cellulose, microbial degradation in conjunction with corrosion can significantly perturb the ambient geochemistry. These processes typically produce a transition from oxidising to reducing conditions and can influence radionuclide migration through changes in both the dominant radionuclide species and mineral phases. The DRINK (DRIgg Near field Kinetic) code is a biogeochemical transport code designed to simulate the long term evolution of the UK low level radioactive waste disposal site at Drigg. Drigg is the UK's principal solid low level radioactive waste disposal site and has been receiving waste since 1959. The interaction between microbial activity, the ambient geochemistry and radionuclide chemistry is central to the DRINK approach with the development of the ambient pH, redox potential and bulk geochemistry being directly influenced by microbial activity. This paper describes the microbial aspects of the code, site data underpinning the microbial model, the microbiology/chemistry interface and provides an example of the code in action. PMID:9340003

  14. The Assessment of Future Human Actions at Radioactive Waste Disposal Sites: An international perspective

    SciTech Connect

    Anderson, D.R.; Galson, D.A.; Patera, E.S.

    1994-04-01

    For some deep geological disposal systems, the level of confinement provided by the natural and engineered barriers is considered to be so high that the greatest long-term risks associated with waste disposal may arise from the possibility of future human actions breaching the natural and/or engineered barrier systems. Following a Workshop in 1989, the OECD Nuclear Energy Agency established a Working Group on Assessment of Future Human Actions (FHA) a Radioactive Waste Disposal Sites. This Group met four times in the period 1991--1993, and has extensively reviewed approaches to and experience of incorporating the effects of FHA into long-term performance assessments (PAs). The Working Group`s report reviews the main issues concerning the treatment of FHA, presents a general framework for the quantitative, consideration of FHA in radioactive waste disposal programmes, and discusses means in reduce the risks associated with FHA. The Working Group concluded that FHA must be considered in PAs, although FHA where the actors were cognizant of the risks could be ignored. Credit can be taken for no more than several hundred years of active site control; additional efforts should therefore be taken to reduce the risks associated with FHA. International agreement on principles for the construction of FHA scenarios would build confidence, as would further discussion concerning regulatory policies for judging risks associated with FHA.

  15. Investigations of the unsaturated zone at two radioactive waste disposal sites in Lithuania.

    PubMed

    Skuratovič, Žana; Mažeika, Jonas; Petrošius, Rimantas; Martma, Tõnu

    2016-01-01

    The unsaturated zone is an important part of the water cycle, governed by many hydrological and hydrogeological factors and processes and provide water and nutrients to the terrestrial ecosystem. Besides, the soils of the unsaturated zone are regarded as the first natural barrier to a large extent and are able to limit the spread of contaminants depending on their properties. The unsaturated zone provides a linkage between atmospheric moisture, groundwater, and seepage of groundwater to streams, lakes, or other surface water bodies. The major difference between water flow in saturated and unsaturated soils is that the hydraulic conductivity, which is conventionally assumed to be a constant in saturated soils, is a function of the degree of saturation or matrix suction in the unsaturated soils. In Lithuania, low and intermediate level radioactive wastes generated from medicine, industry and research were accumulated at the Maisiagala radioactive waste repository. Short-lived low and intermediate levels radioactive waste, generated during the operation of the Ignalina Nuclear Power Plant (INPP) and arising after the INPP decommissioning will be disposed of in the near surface repository close to the INPP (Stabatiske site). Extensive data sets of the hydraulic properties and water content attributed to unsaturated zone soil profiles of the two radioactive waste disposal sites have been collected and summarized. Globally widespread radionuclide tritium ((3)H) and stable isotope ratio ((18)O/(16)O and (2)H/(1)H) distribution features were determined in precipitation, unsaturated zone soil moisture profiles and groundwater. PMID:26586231

  16. Global threat reduction initiative efforts to address transportation challenges associated with the recovery of disused radioactive sealed sources - 10460

    SciTech Connect

    Whitworth, Julie; Abeyta, Cristy L; Griffin, Justin M; Matzke, James L; Pearson, Michael W; Cuthbertson, Abigail; Rawl, Richard; Singley, Paul

    2010-01-01

    Proper disposition of disused radioactive sources is essential for their safe and secure management and necessary to preclude their use in malicious activities. Without affordable, timely transportation options, disused sealed sources remain in storage at hundreds of sites throughout the country and around the world. While secure storage is a temporary measure, the longer sources remain disused or unwanted the chances increase that they will become unsecured or abandoned. The Global Threat Reduction Initiative's Off-Site Source Recovery Project (GTRIlOSRP), recovers thousands of disused and unwanted sealed sources annually as part of GTRl's larger mission to reduce and protect high risk nuclear and radiological materials located at civilian sites worldwide. Faced with decreasing availability of certified transportation containers to support movement of disused and unwanted neutron- and beta/gamma-emitting radioactive sealed sources, GTRIlOSRP has initiated actions to ensure the continued success of the project in timely recovery and management of sealed radioactive sources. Efforts described in this paper to enhance transportation capabilities include: {sm_bullet} Addition of authorized content to existing and planned Type B containers to support the movement of non-special form and other Type B-quantity sealed sources; {sm_bullet} Procurement of vendor services for the design, development, testing and certification of a new Type B container to support transportation of irradiators, teletherapy heads or sources removed from these devices using remote handling capabilities such as the IAEA portable hot cell facility; {sm_bullet} Expansion of shielded Type A container inventory for transportation of gamma-emitting sources in activity ranges requiring use of shielding for conformity with transportation requirements; {sm_bullet} Approval of the S300 Type A fissile container for transport of Pu-239 sealed sources internationally; {sm_bullet} Technology transfer of field

  17. Exposure and risk calculations for disposal of wastes having minimal radioactivity

    SciTech Connect

    Fields, D.E.

    1984-01-01

    The US Nuclear Regulatory Commission is currently considering revision of rules 10 CFR 20 and 10 CFR 61, which cover disposal of solid wastes containing minimal activity radioactivity. In support of these revised rules, we have evaluated the consequences of disposing of four waste streams at four types of disposal areas located in three different geographic regions. Consequences are expressed in terms of human exposures and associated health effects. Each geographic region has its own climate and geology. Example waste streams, waste disposal methods, and geographic regions chosen for this study are clearly specified. The PRESTO-II methodology was used to evaluate radionuclide transport and health effects. This methodology was developed to assess radiological impacts to a static local population for a 1000-year period following disposal. The modeling of pathways and processes of migration from the trench to exposed populations included the following considerations: groundwater transport, overland flow, erosion, surface water dilution, resuspension, atmospheric transport, deposition, inhalation, and ingestion of contaminated beef, milk, crops, and water. 9 references, 2 figures, 3 tables.

  18. Economics of a small-volume low-level radioactive waste disposal facility

    SciTech Connect

    Not Available

    1993-04-01

    This report was prepared by the US Department of Energy National Low-Level Waste Management Program to present the results of a life-cycle cost analysis of a low-level radioactive waste disposal facility, including all support facilities, beginning in the preoperational phase and continuing through post-closure care. The disposal technology selected for this report is earth-covered concrete vaults, which use reinforced concrete vaults constructed above grade and an earth cover constructed at the end of the operational period for permanent closure. The report develops a design, cost estimate, and schedule for the base case and eight alternative scenarios involving changes in total disposal capacity, operating life, annual disposal rate, source of financing and long-term interest rates. The purpose of this analysis of alternatives is to determine the sensitivity of cost to changes in key analytical or technical parameters, thereby evaluating the influence of a broad range of conditions. The total estimated cost of each alternative is estimated and a unit disposal charge is developed.

  19. Hydrogeologic setting east of a low-level radioactive-waste disposal site near Sheffield, Illinois

    USGS Publications Warehouse

    Foster, J.B.; Garklavs, George; Mackey, G.W.

    1984-01-01

    Core samples from 45 test wells and 4 borings were used to describe the glacial geology of the area east of the low-level radioactive-waste disposal site near Sheffield, Bureau County, Illinois. Previous work has shown that shallow ground water beneath the disposal site flows east through a pebbly-sand unit of the Toulon Member of the Glasford Formation. The pebbly sand was found in core samples from wells in an area extending northeast from the waste-disposal site to a strip-mine lake and east along the south side of the lake. Other stratigraphic units identified in the study area are correlated with units found on the disposal site. The pebbly-sand unit of the Toulon Member grades from a pebbly sand on site into a coarse gravel with sand and pebbles towards the lake. The Hulick Till Member, a key bed, underlies the Toulon Member throughout most of the study area. A narrow channel-like depression in the Hulick Till is filled with coarse gravelly sand of the Toulon Member. The filled depression extends eastward from near the northeast corner of the waste-disposal site to the strip-mine lake. (USGS)

  20. Site selection and investigation for subsurface disposal of radioactive wastes in hydraulically induced fractures

    SciTech Connect

    Sun, R.J.

    1980-01-01

    Injection into a thick shale formation of intermediate-level radioactive wastes (specific activity of less than 6 x 10/sup 3/ ..mu..Ci/ml consisting mainly of radionuclides such as strontium and cesium with half-lives of less than 50 years) mixed with cement is a promising and feasible disposal method. Hydraulic fracturing provides openings in the shale to accommodate the wastes. Ion exchange and radionuclide adsorption materials can be added to the grout during mixing to further increase the radionuclide retaining capacity of the grout. After solidification of the grout, the injected wastes become an integral part of the shale formation and thus the wastes will remain at depth and in place as long as the injection zone is not subjected to erosion or dissolution. Problems concerning safety of the disposal method are: (1) potential of inducing vertical fractures; (2) phase separation during and after injections; (3) reliability of methods for determining orientation of induced fractures; (4) possibility of triggering earthquakes; and (5) radionuclides leaching and transporting by ground water. Waste injections are made in multiple-layer injection stages in an injection well. After the first series of injections are made at the greatest depth, the well is plugged by cement at the injection depth. The depth of the second series of injections is located at a suitable distance above the first injection depth. The repeated use of the injection well distributes the cost of construction of injection and monitoring wells over many injections, thereby making hydraulic fracturing and grout injection economically attractive as a method for disposal of radioactive wastes. Theoretical considerations of inducing nearly horizontal bedding-plane fractures in shale and field procedures for site selection, safety, monitoring and operation of radioactive waste disposal are discussed. Case histories are used as examples to demonstrate the theoretical applications and field operations.

  1. Estimating costs of low-level radioactive waste disposal alternatives for the Commonwealth of Massachusetts

    SciTech Connect

    Not Available

    1994-02-01

    This report was prepared for the Commonwealth of Massachusetts by the Idaho National Engineering Laboratory, National Low-Level Waste Management Program. It presents planning life-cycle cost (PLCC) estimates for four sizes of in-state low-level radioactive waste (LLRW) disposal facilities. These PLCC estimates include preoperational and operational expenditures, all support facilities, materials, labor, closure costs, and long-term institutional care and monitoring costs. It is intended that this report bc used as a broad decision making tool for evaluating one of the several complex factors that must be examined when deciding between various LLRW management options -- relative costs. Because the underlying assumptions of these analyses will change as the Board decides how it will manage Massachusett`s waste and the specific characteristics any disposal facility will have, the results of this study are not absolute and should only be used to compare the relative costs of the options presented. The disposal technology selected for this analysis is aboveground earth-mounded vaults. These vaults are reinforced concrete structures where low-level waste is emplaced and later covered with a multi-layered earthen cap. The ``base case`` PLCC estimate was derived from a preliminary feasibility design developed for the Illinois Low-Level Radioactive Waste Disposal Facility. This PLCC report describes facility operations and details the procedure used to develop the base case PLCC estimate for each facility component and size. Sensitivity analyses were performed on the base case PLCC estimate by varying several factors to determine their influences upon the unit disposal costs. The report presents the results of the sensitivity analyses for the five most significant cost factors.

  2. Formation of stable uranium(VI) colloidal nanoparticles in conditions relevant to radioactive waste disposal.

    PubMed

    Bots, Pieter; Morris, Katherine; Hibberd, Rosemary; Law, Gareth T W; Mosselmans, J Frederick W; Brown, Andy P; Doutch, James; Smith, Andrew J; Shaw, Samuel

    2014-12-01

    The favored pathway for disposal of higher activity radioactive wastes is via deep geological disposal. Many geological disposal facility designs include cement in their engineering design. Over the long term, interaction of groundwater with the cement and waste will form a plume of a hyperalkaline leachate (pH 10-13), and the behavior of radionuclides needs to be constrained under these extreme conditions to minimize the environmental hazard from the wastes. For uranium, a key component of many radioactive wastes, thermodynamic modeling predicts that, at high pH, U(VI) solubility will be very low (nM or lower) and controlled by equilibrium with solid phase alkali and alkaline-earth uranates. However, the formation of U(VI) colloids could potentially enhance the mobility of U(VI) under these conditions, and characterizing the potential for formation and medium-term stability of U(VI) colloids is important in underpinning our understanding of U behavior in waste disposal. Reflecting this, we applied conventional geochemical and microscopy techniques combined with synchrotron based in situ and ex situ X-ray techniques (small-angle X-ray scattering and X-ray adsorption spectroscopy (XAS)) to characterize colloidal U(VI) nanoparticles in a synthetic cement leachate (pH > 13) containing 4.2-252 μM U(VI). The results show that in cement leachates with 42 μM U(VI), colloids formed within hours and remained stable for several years. The colloids consisted of 1.5-1.8 nm nanoparticles with a proportion forming 20-60 nm aggregates. Using XAS and electron microscopy, we were able to determine that the colloidal nanoparticles had a clarkeite (sodium-uranate)-type crystallographic structure. The presented results have clear and hitherto unrecognized implications for the mobility of U(VI) in cementitious environments, in particular those associated with the geological disposal of nuclear waste. PMID:25418066

  3. Packaging, Transportation, and Disposal Logistics for Large Radioactively Contaminated Reactor Decommissioning Components

    SciTech Connect

    Lewis, Mark S.

    2008-01-15

    The packaging, transportation and disposal of large, retired reactor components from operating or decommissioning nuclear plants pose unique challenges from a technical as well as regulatory compliance standpoint. In addition to the routine considerations associated with any radioactive waste disposition activity, such as characterization, ALARA, and manifesting, the technical challenges for large radioactively contaminated components, such as access, segmentation, removal, packaging, rigging, lifting, mode of transportation, conveyance compatibility, and load securing require significant planning and execution. In addition, the current regulatory framework, domestically in Titles 49 and 10 and internationally in TS-R-1, does not lend itself to the transport of these large radioactively contaminated components, such as reactor vessels, steam generators, reactor pressure vessel heads, and pressurizers, without application for a special permit or arrangement. This paper addresses the methods of overcoming the technical and regulatory challenges. The challenges and disposition decisions do differ during decommissioning versus component replacement during an outage at an operating plant. During decommissioning, there is less concern about critical path for restart and more concern about volume reduction and waste minimization. Segmentation on-site is an available option during decommissioning, since labor and equipment will be readily available and decontamination activities are routine. The reactor building removal path is also of less concern and there are more rigging/lifting options available. Radionuclide assessment is necessary for transportation and disposal characterization. Characterization will dictate the packaging methodology, transportation mode, need for intermediate processing, and the disposal location or availability. Characterization will also assist in determining if the large component can be transported in full compliance with the transportation

  4. Evaluation of exposure pathways to man from disposal of radioactive materials into sanitary sewer systems

    SciTech Connect

    Kennedy, W.E. Jr.; Parkhurst, M.A.; Aaberg, R.L.; Rhoads, K.C.; Hill, R.L.; Martin, J.B.

    1992-05-01

    In accordance with 10 CFR 20, the US Nuclear Regulatory Commission (NRC) regulates licensees` discharges of small quantities of radioactive materials into sanitary sewer systems. This generic study was initiated to examine the potential radiological hazard to the public resulting from exposure to radionuclides in sewage sludge during its treatment and disposal. Eleven scenarios were developed to characterize potential exposures to radioactive materials during sewer system operations and sewage sludge treatment and disposal activities and during the extended time frame following sewage sludge disposal. Two sets of deterministic dose calculations were performed; one to evaluate potential doses based on the radionuclides and quantities associated with documented case histories of sewer system contamination and a second, somewhat more conservative set, based on theoretical discharges at the maximum allowable levels for a more comprehensive list of 63 radionuclides. The results of the stochastic uncertainty and sensitivity analysis were also used to develop a collective dose estimate. The collective doses for the various radionuclides and scenarios range from 0.4 person-rem for {sup 137}Cs in Scenario No. 5 (sludge incinerator effluent) to 420 person-rem for {sup 137}Cs in Scenario No. 3 (sewage treatment plant liquid effluent). None of the 22 scenario/radionuclide combinations considered have collective doses greater than 1000 person-rem/yr. However, the total collective dose from these 22 combinations was found to be about 2100 person-rem.

  5. Selection and investigation of sites for the disposal of radioactive wastes in hydraulically induced subsurface fractures

    SciTech Connect

    Sun, R.J.

    1982-01-01

    Injection of intermediate-level radioactive wastes (specific activity of less than 6 x 10/sup 3/ ..mu..Ci/mL, consisting mainly of radionuclides, such as strontium and cesium, having half-lives of less than 50 years) mixed with cement into a thick shale formation is a promising and feasible disposal method. Hydraulic fracturing provides openings in the shale to accommodate the wastes. Ion exchange and radionuclide-adsorption materials can be added to the grout during mixing to further increase the radionuclide-retaining capacity of the grout. After solidification of the grout, the injected wastes become an integral part of the shale formation, and therefore the wastes will remain at depth and in place as long as the injection zone is not subjected to erosion and dissolution. Problems concerning safety of the disposal method are (1) the potential for inducing vertical fractures, (2) phase separation during and after the injections, (3) the reliability of methods for determining the orientation of induced fractures, (4) the possibility of triggering earthquakes, and (5) radionuclides being leached and transported by ground water. Theoretical considerations about inducing nearly horizontal bedding-plane fractures in shale are discussed, as are field procedures for site selection, safety, and the monitoring and operation of radioactive waste disposal. Case histories are used as examples to demonstrate the application of the theory and techniques of field operations. (JMT)

  6. Selection and investigation of sites for the disposal of radioactive wastes in hydraulically induced subsurface fractures

    SciTech Connect

    Sun, R.J.

    1982-01-01

    Injection of intermediate-level radioactive wastes (specific activity of less than 6 x 10/sup 3/..mu..Ci/mL, consisting mainly of radionuclides, such as strontium and cesium, having half-lives of less than 50 years) mixed with cement into a thick shale formation is a promising and feasible disposal method. Hydraulic fracturing provides openings in the shale to accommodate the wastes. Ion exchange and radionuclide-adsorption materials can be added to the grout during mixing to further increase the radionuclide-retaining capacity of the grout. After solidification of the grout, the injected wastes become an integral part of the shale formation, and therefore the wastes will remain at depth and in place as long as the injection zone is not subjected to erosion or dissolution. Problems concerning safety of the disposal method are: (1) the potential for inducing vertical fractures, (2) phase separation during and after the injections, (3) the reliability of methods for determining the orientation of induced fractures, (4) the possibility of triggering earthquakes, and (5) radionuclides being leached and transported by ground water. Theoretical considerations about inducing nearly horizontal bedding-plane fractures in shale are discussed, as are field procedures for site selection, safety, and the monitoring and operation of radioactive waste disposal. Case histories are used as examples to demonstrate the application of the theory and techniques of field operations.

  7. Code System For Risk Assessment From Underground Radioactive Waste Disposal In the United Kingdom.

    Energy Science and Technology Software Center (ESTSC)

    2000-04-18

    Version 00 The SYVAC D/2 program simulates the ground water mediated movement of radionuclides from underground facilities for the disposal of low and intermediate level wastes to the accessible environment, and provides an estimate of the subsequent radiological risk to man. The simulated timescales are usually within the range 1.0E+03 to 1.0E+07 years. SYVAC is capable of modelling both shallow disposal facilities (located in argillaceous media and overlaying an aquifer) and deep disposal facilities (inmore » a saturated environment). The software was developed for use within the UK Department of the Environment (DOE) Radioactive Waste Management Programme, as one tool in the DOE Assessment Methodology. The acronym SYVAC (System Variability Analysis Code for deep and shallow burial of radioactive waste) comes from the name of an assessment code originally obtained from the Atomic Energy of Canada (AECL) in 1982, which was found to be inappropriate for geological conditions in the UK. The development of the previous version, SYVAC A/C, was undertaken by the following private installations under UK Department of the Environment (DOE) contracts: Atkins Research & Development, Epsom, Surrey, England; Associated Nuclear Services, Epsom, Surrey, England; CAP Scientific, London, England; Electrowatt Engineering Services, Horsham, West Sussex, England; and Scicon Limited, Wavendon, Milton Kenes, England.« less

  8. Assessment of microbial processes on gas production at radioactive low-level waste disposal sites

    SciTech Connect

    Weiss, A.J.; Tate, R.L. III; Colombo, P.

    1982-05-01

    Factors controlling gaseous emanations from low level radioactive waste disposal sites are assessed. Importance of gaseous fluxes of methane, carbon dioxide, and possible hydrogen from the site, stems from the inclusion of tritium and/or carbon-14 into the elemental composition of these compounds. In that the primary source of these gases is the biodegradation of organic components of the waste material, primary emphasis of the study involved an examination of the biochemical pathways producing methane, carbon dioxide, and hydrogen, and the environmental parameters controlling the activity of the microbial community involved. Initial examination of the data indicates that the ecosystem is anaerobic. As the result of the complexity of the pathway leading to methane production, factors such as substrate availability, which limit the initial reaction in the sequence, greatly affect the overall rate of methane evolution. Biochemical transformations of methane, hydrogen and carbon dioxide as they pass through the soil profile above the trench are discussed. Results of gas studies performed at three commercial low level radioactive waste disposal sites are reviewed. Methods used to obtain trench and soil gas samples are discussed. Estimates of rates of gas production and amounts released into the atmosphere (by the GASFLOW model) are evaluated. Tritium and carbon-14 gaseous compounds have been measured in these studies; tritiated methane is the major radionuclide species in all disposal trenches studied. The concentration of methane in a typical trench increases with the age of the trench, whereas the concentration of carbon dioxide is similar in all trenches.

  9. Geohydrologic aspects for siting and design of low-level radioactive-waste disposal

    USGS Publications Warehouse

    Bedinger, M.S.

    1989-01-01

    The objective for siting and design of low-level radioactive-waste repository sites is to isolate the waste from the biosphere until the waste no longer poses an unacceptable hazard as a result of radioactive decay. Low-level radioactive waste commonly is isolated at shallow depths with various engineered features to stabilize the waste and to reduce its dissolution and transport by ground water. The unsaturated zone generally is preferred for isolating the waste. Low-level radioactive waste may need to be isolated for 300 to 500 years. Maintenance and monitoring of the repository site are required by Federal regulations for only the first 100 years. Therefore, geohydrology of the repository site needs to provide natural isolation of the waste for the hazardous period following maintenance of the site. Engineering design of the repository needs to be compatible with the natural geohydrologic conditions at the site. Studies at existing commercial and Federal waste-disposal sites provide information on the problems encountered and the basis for establishing siting guidelines for improved isolation of radioactive waste, engineering design of repository structures, and surveillance needs to assess the effectiveness of the repositories and to provide early warning of problems that may require remedial action. Climate directly affects the hydrology of a site and probably is the most important single factor that affects the suitability of a site for shallow-land burial of low-level radioactive waste. Humid and subhumid regions are not well suited for shallow isolation of low-level radioactive waste in the unsaturated zone; arid regions with zero to small infiltration from precipitation, great depths to the water table, and long flow paths to natural discharge areas are naturally well suited to isolation of the waste. The unsaturated zone is preferred for isolation of low-level radioactive waste. The guiding rationale is to minimize contact of water with the waste and to

  10. History of disposal of radioactive wastes into the ground at Oak Ridge National Laboratory

    SciTech Connect

    Coobs, J.H.; Gissel, J.R.

    1986-10-01

    Since the beginning of operations at the Oak Ridge National Laboratory (ORNL) in 1943, shallow land burial has been used for the disposal of solid low-level radioactive waste. These wastes have originated from nearly every operating facility, and from 1955 to 1963, ORNL's solid waste storage areas were designated by the Atomic Energy Commission (AEC) as the Southern Regional Burial Ground. During this period, about one million cubic feet of solid waste from various off-site installations were buried in solid waste storage areas (SWSAs) 4 and 5. Six SWSAs have been used since land burial operations began at ORNL in early 1944. ORNL has generated liquid radioactive waste since the separation of plutonium began in 1944. The majority of these wastes are classified as process (low-level) waste and are derived from evaporator condensate and cooling water from process vessels, and from building drains and surface drainage from contaminated areas. Process wastes are monitored at sampling stations located strategicially throughout the plant, and for nearly 15 years (1944 to 1957) they were discharged directly into White Oak Creek without being treated chemically to remove radionuclides. A smaller quantity of intermediate-level wastes (ILW) originate from the radiochemical separation process and from test reactors. The collection, treatment, and methods of disposal of ILW from the years 1943 to 1981 are described. Over this period of time there was a great deal of variation in the amounts and types of radioactive liquid wastes generated.

  11. Aboveground roofed design for the disposal of low-level radioactive waste in Maine

    SciTech Connect

    Alexander, J.A.

    1993-03-01

    The conceptual designs proposed in this report resulted from a study for the Maine Low-level Radioactive Waste Authority to develop conceptual designs for a safe and reliable disposal facility for Maine`s low-level radioactive waste (LLW). Freezing temperatures, heavy rainfall, high groundwater tables, and very complex and shallow glaciated soils found in Maine place severe constraints on the design. The fundamental idea behind the study was to consider Maine`s climatic and geological conditions at the beginning of conceptual design rather than starting with a design for another location and adapting it for Maine`s conditions. The conceptual designs recommended are entirely above ground and consist of an inner vault designed to provide shielding and protection against inadvertent intrusion and an outer building to protect the inner vault from water. The air dry conditions within the outer building should lead to almost indefinite service life for the concrete inner vault and the waste containers. This concept differs sharply from the usual aboveground vault in its reliance on at least two independent, but more or less conventional, roofing systems for primary and secondary protection against leakage of radioisotopes from the facility. Features include disposal of waste in air dry environment, waste loading and visual inspection by remote-controlled overhead cranes, and reliance on engineered soils for tertiary protection against release of radioactive materials.

  12. 1997 State-by-State Assessment of Low-Level Radioactive Wastes Received at Commercial Disposal Sites

    SciTech Connect

    Fuchs, R. L.

    1998-08-01

    Each year the National Low-Level Waste Management Program publishes a state-by-state assessment report. This report provides both national and state-specific disposal data on low-level radioactive waste commercially disposed in the United States. Data in this report are categorized according to disposal site, generator category, waste class, volumes, and radionuclide activity. Included in this report are tables showing the distribution of waste by state for 1997 and a comparison of waste volumes and radioactivity by state for 1993 through 1997; also included is a list of all commercial nuclear power reactors in the United States as of December 31, 1997.

  13. Use of fly-ash for sealing a radioactive waste repository

    SciTech Connect

    Ollagnier, M.; Tauziede, C.; Olivier, J.

    1993-12-31

    The mining industry currently uses fly-ash from coal-fired power-plants to close access shafts in abandoned mines, in sedimentary formations. The technique consists of installing a plug of fly-ash, about fifty meters high, at the base of the shaft-lining. In this study, fly-ash is considered as a possible sealant for radioactive repositories in sedimentary formations, as well as in hard rock. Specific studies have been conducted in order to assess the feasibility of this technique, and to improve the long-term performance of the fly-ash seals. The hydraulic and mechanical characteristics of fly-ash, taken from the plug of an abandoned shaft, as well as from dumps of various ages, were measured. Laboratory tests showed that it is possible to reduce the hydraulic conductivity of fly-ash by a factor of thousand, with the addition of ten percent bentonite. Moreover, it seems possible to block fine fissures in the surrounding damaged rock by injecting grouts made of cement and fly-ash having maximum diameters of twenty micrometers.

  14. 1996 state-by-state assessment of low-level radioactive wastes received at commercial disposal sites

    SciTech Connect

    Fuchs, R.L.

    1997-09-01

    Each year the National Low-Level Waste Management Program publishes a state-by-state assessment report. This report provides both national and state-specific disposal data on low-level radioactive waste commercially disposed in the US. Data in this report are categorized according to disposal site, generator category, waste class, volumes, and radionuclide activity. Included in this report are tables showing the distribution of waste by state for 1996 and a comparison of waste volumes and radioactivity by state for 1992 through 1996; also included is a list of all commercial nuclear power reactors in the US as of December 31, 1996. This report distinguishes between low-level radioactive waste shipped directly for disposal by generators and waste that was handled by an intermediary, a reporting change introduced in the 1988 state-by-state report.

  15. 1995 state-by-state assessment of low-level radioactive wastes received at commercial disposal sites

    SciTech Connect

    Fuchs, R.L.

    1996-09-01

    Each year the National Low-Level Waste Management Program publishes a state-by-state assessment report. This report provides both national and state-specific disposal data on low-level radioactive waste commercially disposed in US. Data in this report are categorized according to disposal site, generator category, waste class, volumes, and radionuclide activity. Included are tables showing the distribution of waste by state for 1995 and a comparison of waste volumes and radioactivity by state for 1991 through 1995; also included is a list of all commercial nuclear power reactors in US as of Dec. 31, 1994. This report distinguishes low-level radioactive waste shipped directly for disposal by generators and waste handled by an intermediary.

  16. Tritium migration from a low-level radioactive-waste disposal site near Chicago, Illinois

    USGS Publications Warehouse

    Nicholas, J.R.; Healy, R.W.

    1988-01-01

    This paper describes the results of a study to determine the geologic and hydrologic factors that control migration of tritium from a closed, low-level radioactive-waste disposal site. The disposal site, which operated from 1943 to mid1949, contains waste generated by research activities at the world's first nuclear reactors. Tritium has migrated horizontally at least 1,300 feet northward in glacial drift and more than 650 feet in the underlying dolomite. Thin, gently sloping sand layers in an otherwise clayey glacial drift are major conduits for ground-water flow and tritium migration in a perched zone beneath the disposal site. Tritium concentrations in the drift beneath the disposal site exceed 100,000 nanocuries per liter. Regional horizontal joints in the dolomite are enlarged by solution and are the major conduits for ground-water flow and tritium migration in the dolomite. A weathered zone at the top of the dolomite also is a pathway for tritium migration. The maximum measured tritium concentration in the dolomite is 29.4 nanocuries per liter. Fluctuations of tritium concentration in the dolomite are the result of dilution by seasonal recharge from the drift.

  17. A data base for low-level radioactive waste disposal sites

    SciTech Connect

    Daum, M.L.; Moskowitz, P.D.

    1989-07-01

    A computerized database was developed to assist the US Environmental Protection Agency (EPA) in evaluating methods and data for characterizing health hazards associated with land and ocean disposal options for low-level radioactive wastes. The data cover 1984 to 1987. The types of sites considered include Nuclear Regulatory Commission (NRC) licensed commercial disposal sites, EPA National Priority List (NPL) sites, US Department of Energy (DOE) Formerly Utilized Sites Remedial Action Project (FUSRAP) and DOE Surplus Facilities Management Program (SFMP) sites, inactive US ocean disposal sites, and DOE/Department of Defense facilities. Sources of information include reports from EPA, the US Department of Energy (DOE) and the Nuclear Regulatory Commission (NRC), as well as direct communication with individuals associated with specific programs. The data include site descriptions, waste volumes and activity levels, and physical and radiological characterization of low-level wastes. Additional information on mixed waste, packaging forms, and disposal methods were compiled, but are not yet included in the database. 55 refs., 4 figs., 2 tabs.

  18. Subseabed Radioactive Waste Disposal Feasibility Program: ocean engineering challenges for the 80's

    SciTech Connect

    Talbert, D. M.

    1980-01-01

    The objective of the Subseabed Disposal Program is to assess the feasibility of disposing of high-level radioactive wastes or spent fuel in suitable geologic formations beneath the deep ocean floor. The program is entering a phase which will address engineering feasibility. While the current phase of the program to determine the scientific and environmental feasibility of the concept is not yet complete, activities to assess the engineering aspects are being initiated in parallel to facilitate the development of the concept on a time scale commensurate with other related programs both in the United States and abroad. It is anticipated that engineering aspects will become the central focus of the program during the early 80's and will continue so through the establishment of a pilot-plant level activity which could occur by the mid-90's.

  19. Space transportation and destination considerations for extraterrestrial disposal of radioactive waste

    NASA Technical Reports Server (NTRS)

    Zimmerman, A. V.; Thompson, R. L.; Lubick, R. J.

    1973-01-01

    A feasibility study is summarized of extraterrestrial (space) disposal of radioactive waste. The initial work on the evaluation and comparison of possible space destinations and launch vehicles is reported. Only current or planned space transportation systems were considered. The currently planned space shuttle was found to be more cost effective than current expendable launch vehicles, by about a factor of two. The space shuttle will require a third stage to perform the disposal missions. Depending on the particular mission this could be either a reusable space tug or an expendable stage such as a Centaur. Of the destinations considered, high earth orbits (between geostationary and lunar orbit altitudes), solar orbits (such as a 0.90 AU circular solar orbit) or a direct injection to solar system escape appear to be the best candidates. Both earth orbits and solar orbits have uncertainties regarding orbit stability and waste package integrity for times on the order of a million years.

  20. Evaluation of alternatives for high-level and transuranic radioactive- waste disposal standards

    SciTech Connect

    Klett, R.D.; Gruebel, M.M.

    1992-12-01

    The remand of the US Environmental Protection Agency`s long-term performance standards for radioactive-waste disposal provides an opportunity to suggest modifications that would make the regulation more defensible and remove inconsistencies yet retain the basic structure of the original rule. Proposed modifications are in three specific areas: release and dose limits, probabilistic containment requirements, and transuranic-waste disposal criteria. Examination of the modifications includes discussion of the alternatives, demonstration of methods of development and implementation, comparison of the characteristics, attributes, and deficiencies of possible options within each area, and analysis of the implications for performance assessments. An additional consideration is the impact on the entire regulation when developing or modifying the individual components of the radiological standards.

  1. Safety Assessment for VLLW Disposal at the National Radioactive Waste Repository Mochovce in Slovakia - 13508

    SciTech Connect

    Biurrun, E.; Haverkamp, B.; Lazaro, A.; Miralles, A.

    2013-07-01

    Recent developments in the Slovak Republic have prompted the need to introduce the new category of very low level waste (VLLW) in the operation of the country's repository for low and intermediate level radioactive waste (LILW). By doing this, significant savings are expected to be achieved while disposing the waste resulting from early decommissioning of older, Soviet type reactors. To study the feasibility and the likely impact of such introduction, a project was launched and assigned in international competition to a German-Spanish consortium. The study confirmed by means of a safety assessment the feasibility of this waste category in the specific context of the Slovakian repository. Moreover, the advantages that such new waste category would render were stressed and the best option for enlargement of the repository, the construction of a module for LILW disposal within the limits of the existing repository, was identified. (authors)

  2. European concepts for shared storage and disposal facilities for radioactive wastes?

    SciTech Connect

    Verhoef, Ewoud; Codee, Hans; Stefula, Vladan; McCombie, Charles

    2007-07-01

    Geological disposal is an essential component of the long-term management of spent fuel and high-level radioactive waste. Implementation of a suitable deep repository may, however, be difficult or impossible in some (especially small) countries because of challenging geological conditions or restricted siting options, or because of the high costs involved. For these countries, shared regional or international storage and disposal facilities are a necessity. The European Parliament and the EC have both expressed support for concepts that could lead to regional shared facilities being implemented in the EU. The EC, therefore, funded two projects that form the first two steps of a staged process towards the implementation of shared regional or international storage and disposal facilities. In the period 2003 to 2005, the EC funded SAPIERR I, a project devoted to pilot studies on the feasibility of shared regional storage facilities and geological repositories, for use by European countries. The studies showed that shared regional repositories are feasible, but also that, if they are to be implemented, even some decades ahead, efforts must already be increased now. The first step would be to establish a structured framework for the work on regional repositories. This is the goal of SAPIERR II (2006-2008): to develop possible practical implementation strategies and organisational structures. These will enable a formalised, structured European Development Organisation (EDO) to be established in 2008 or afterwards for working on shared EU radioactive waste storage and disposal activities. The EDO can work in parallel with national waste programmes. Participating EU Member States will be able to use the structures developed as, when and if needed for the furtherance of their individual national policies. (authors)

  3. Readiness assessment plan for the Radioactive Mixed Waste Land Disposal Facility (Trench 31)

    SciTech Connect

    Irons, L.G.

    1994-11-22

    This document provides the Readiness Assessment Plan (RAP) for the Project W-025 (Radioactive Mixed Waste Land Disposal Facility) Readiness Assessment (RA). The RAP documents prerequisites to be met by the operating organization prior to the RA. The RAP is to be implemented by the RA Team identified in the RAP. The RA Team is to verify the facility`s compliance with criteria identified in the RAP. The criteria are based upon the {open_quotes}Core Requirements{close_quotes} listed in DOE Order 5480.31, {open_quotes}Startup and Restart of Nuclear Facilities{close_quotes}.

  4. Model tracking system for low-level radioactive waste disposal facilities: License application interrogatories and responses

    SciTech Connect

    Benbennick, M.E.; Broton, M.S.; Fuoto, J.S.; Novgrod, R.L.

    1994-08-01

    This report describes a model tracking system for a low-level radioactive waste (LLW) disposal facility license application. In particular, the model tracks interrogatories (questions, requests for information, comments) and responses. A set of requirements and desired features for the model tracking system was developed, including required structure and computer screens. Nine tracking systems were then reviewed against the model system requirements and only two were found to meet all requirements. Using Kepner-Tregoe decision analysis, a model tracking system was selected.

  5. Models for estimation of service life of concrete barriers in low-level radioactive waste disposal

    SciTech Connect

    Walton, J.C.; Plansky, L.E.; Smith, R.W. )

    1990-09-01

    Concrete barriers will be used as intimate parts of systems for isolation of low level radioactive wastes subsequent to disposal. This work reviews mathematical models for estimating the degradation rate of concrete in typical service environments. The models considered cover sulfate attack, reinforcement corrosion, calcium hydroxide leaching, carbonation, freeze/thaw, and cracking. Additionally, fluid flow, mass transport, and geochemical properties of concrete are briefly reviewed. Example calculations included illustrate the types of predictions expected of the models. 79 refs., 24 figs., 6 tabs.

  6. Life cycle costs for disposal and assured isolation of low-level radioactive waste in Connecticut

    SciTech Connect

    Chau, B.; Sutherland, A.A.; Baird, R.D.

    1998-03-01

    This document presents life cycle costs for a low-level radioactive disposal facility and a comparable assured isolation facility. Cost projections were based on general plans and assumptions, including volume projections and operating life, provided by the Connecticut Hazardous Waste Management Service, for a facility designed to meet the State`s needs. Life cycle costs include the costs of pre-construction activities, construction, operations, closure, and post-closure institutional control. In order to provide a better basis for understanding the relative magnitude of near-term costs and future costs, the results of present value analysis of ut-year costs are provided.

  7. Development of Wireless Data Transmission System for the Monitoring in Geological Disposal of Radioactive Waste - 12063

    SciTech Connect

    Suzuki, Kei; Eto, Jiro; Tanabe, Hiromi; Esaki, Taichi; Takamura, Hisashi; Suyama, Yasuhiro

    2012-07-01

    The authors have been developing a wireless data transmission system to monitor the performance of a geological disposal system for radioactive waste. The system's concepts, advantages, and a recent development focused on reducing transmitter size to suit narrow spaces such as bentonite buffers and boreholes. A wireless transmitter with a built-in temperature sensor and a connector for external sensors has been developed, measuring 130 mm in length and 50 mm in diameter. The capability of the transmitter was confirmed by transmission tests on the ground and in a bentonite block. (authors)

  8. An overview of radioactive waste disposal procedures of a nuclear medicine department.

    PubMed

    Ravichandran, R; Binukumar, J P; Sreeram, Rajan; Arunkumar, L S

    2011-04-01

    Radioactive wastes from hospitals form one of the various types of urban wastes, which are managed in developed countries in a safe and organized way. In countries where growth of nuclear medicine services are envisaged, implementations of existing regulatory policies and guidelines in hospitals in terms of handling of radioactive materials used in the treatment of patients need a good model. To address this issue, a brief description of the methods is presented. A designed prototype waste storage trolley is found to be of great help in decaying the I-131 solid wastes from wards before releasing to waste treatment plant of the city. Two delay tanks with collection time of about 2 months and delay time of 2 months alternately result in 6 releases of urine toilet effluents to the sewage treatment plant (STP) of the hospital annually. Samples of effluents collected at releasing time documented radioactive releases of I-131 much below recommended levels of bi-monthly release. External counting of samples showed good statistical correlation with calculated values. An overview of safe procedures for radioactive waste disposal is presented. PMID:21731225

  9. Evaluation of a method for designing sealing plugs for HLW geological disposal facilities, taking into account the heterogeneous characteristics of the geological environment

    SciTech Connect

    Suyama, Yasuhiro; Yanagizawa, Koichi; Toida, Masaru

    2007-07-01

    In order to ensure that a repository for the geological disposal of HLW is isolated from the human environment, underground excavations, including pits and tunnels, must be properly sealed. Effective sealing requires that these excavations are backfilled, and that the Excavation Damage or Disturbed Zone (EDZ), which includes preferential flow paths, must be intersected by sealing plugs. Methods for constructing a full-scale sealing plug and their influence on plug performance were evaluated and confirmed by a Tunnel Sealing Experiment (TSX). This experiment was carried out by an international partnership of the Japan Nuclear Cycle Development Institute (JNC) and Atomic Energy of Canada Limited (AECL). However certain specific roles of the scaling plugs at the scale of the whole repository were not studied. There remain issues to be clarified, notably the effectiveness of sealing plugs in a geological environment with heterogeneous characteristics and the resulting influences of the heterogeneities in performance assessment. Focusing on a geological environment with spatially heterogeneous characteristics, the authors have developed a method for designing the sealing plugs, based on a concept of 'primarily design for closure, secondarily design for construction'. Though the proposed method for designing sealing plugs has presently been developed only at a conceptual level, it indicates the possibility of establishing a repository even in a strongly heterogeneous geological environment that may have been considered previously to be inappropriate for a repository. (authors)

  10. Use of engineered soils and other site modifications for low-level radioactive waste disposal

    SciTech Connect

    Not Available

    1994-08-01

    The U.S. Nuclear Regulatory Commission requires that low-level radioactive waste (LLW) disposal facilities be designed to minimize contact between waste and infiltrating water through the use of site design features. The purpose of this investigation is to identify engineered barriers and evaluate their ability to enhance the long-term performance of an LLW disposal facility. Previously used barriers such as concrete overpacks, vaults, backfill, and engineered soil covers, are evaluated as well as state-of-the-art barriers, including an engineered sorptive soil layer underlying a facility and an advanced design soil cover incorporating a double-capillary layer. The purpose of this investigation is also to provide information in incorporating or excluding specific engineered barriers as part of new disposal facility designs. Evaluations are performed using performance assessment modeling techniques. A generic reference disposal facility design is used as a baseline for comparing the improvements in long-term performance offered by designs incorporating engineered barriers in generic and humid environments. These evaluations simulate water infiltration through the facility, waste leaching, radionuclide transport through the facility, and decay and ingrowth. They also calculate a maximum (peak annual) dose for each disposal system design. A relative dose reduction factor is calculated for each design evaluated. The results of this investigation are presented for concrete overpacks, concrete vaults, sorptive backfill, sorptive engineered soil underlying the facility, and sloped engineered soil covers using a single-capillary barrier and a double-capillary barrier. Designs using combinations of barriers are also evaluated. These designs include a vault plus overpacks, sorptive backfill plus overpacks, and overpack with vault plus sorptive backfill, underlying sorptive soil, and engineered soil cover.

  11. Radiological risk assessment and biosphere modelling for radioactive waste disposal in Switzerland.

    PubMed

    Brennwald, M S; van Dorp, F

    2009-12-01

    Long-term safety assessments for geological disposal of radioactive waste in Switzerland involve the demonstration that the annual radiation dose to humans due to the potential release of radionuclides from the waste repository into the biosphere will not exceed the regulatory limit of 0.1 mSv. Here, we describe the simple but robust approach used by Nagra (Swiss National Cooperative for the Disposal of Radioactive Waste) to quantify the dose to humans as a result to time-dependent release of radionuclides from the geosphere into the biosphere. The model calculates the concentrations of radionuclides in different terrestrial and aquatic compartments of the surface environment. The fluxes of water and solids within the environment are the drivers for the exchange of radionuclides between these compartments. The calculated radionuclide concentrations in the biosphere are then used to estimate the radiation doses to humans due to various exposure paths (e.g. ingestion of radionuclides via drinking water and food, inhalation of radionuclides, external irradiation from radionuclides in soils). In this paper we also discuss recent new achievements and planned future work. PMID:19560845

  12. Safety monitoring of the FBG sensor in respect of radioactivity and deformation measurement of a silo structure for radioactive waste disposal

    NASA Astrophysics Data System (ADS)

    Kim, Ki-Soo; Cho, Seong-Kyu

    2015-07-01

    The FBG sensor has globally been commercialized in various fields that is actively applied in Korea as well. Especially it is widely used as a structural monitoring sensor in civil engineering and construction structures due to its advantages including electrical stability, chemical stability and multiplexing. This report aims to introduce safety inspection of the FBG sensor in respect of radioactivity which has been applied to a silo structure for radioactive waste disposal as an example.

  13. Survey of degradation modes of candidate materials for high-level radioactive-waste disposal containers

    SciTech Connect

    Gdowski, G.E.; Bullen, D.B. )

    1988-08-01

    Six alloys are being considered as possible materials for the fabrication of containers for the disposal of high-level radioactive waste. Three of these candidate materials are copper-based alloys: CDA 102 (oxygen-free copper), CDA 613 (Cu-7Al), and CDA 715 (Cu-30Ni). The other three are iron- to nickel-based austenitic materials: Types 304L and 316L stainless steels and Alloy 825. Radioactive waste will include spent-fuel assemblies from reactors as well as waste in borosilicate glass and will be sent to the prospective site at Yucca Mountain, Nevada, for disposal. The waste-package containers must maintain substantially complete containment for at least 300 yr and perhaps as long as 1000 yr. During the first 50 yr after emplacement, the containers must be retrievable from the disposal site. Shortly after emplacement of the containers in the repository, they will be exposed to high temperatures and high gamma radiation fields from the decay of high-level waste. This radiation will promote the radiolytic decomposition of moist air to hydrogen. This volume surveys the available data on the effects of hydrogen on the six candidate alloys for fabrication of the containers. For copper, the mechanism of hydrogen embrittlement is discussed, and the effects of hydrogen on the mechanical properties of the copper-based alloys are reviewed. The solubilities and diffusivities of hydrogen are documented for these alloys. For the austenitic materials, the degradation of mechanical properties by hydrogen is documented. The diffusivity and solubility of hydrogen in these alloys are also presented. For the copper-based alloys, the ranking according to resistance to detrimental effects of hydrogen is: CDA 715 (best) > CDA 613 > CDA 102 (worst). For the austenitic alloys, the ranking is: Type 316L stainless steel {approx} Alloy 825 > Type 304L stainless steel (worst). 87 refs., 19 figs., 8 tabs.

  14. Feasibility of disposal of high-level radioactive wastes into the seabed: Engineering

    SciTech Connect

    Hickerson, J.; Freeman, T.J.; Boisson, J.Y.; Gera, F.; Murray, N.; Nakamura, H.; Nieuwenhuis, J.D.; Schaller, K.H.

    1988-04-01

    This report summarizes the work of the Engineering Studies Task Group (ESTG) of the Seabed Working Group during its study of emplacement systems for the subseabed disposal of high level radioactive waste. ESTG has performed design studies of emplacement systems, costed them, and estimated operational reliabilities. Mathematical models for important physical and engineering processes were developed and a large number of laboratory tests, sea trials, and in situ experiments for the purpose of understanding the emplacement environment and developing the specialized equipment necessary for emplacement were performed. Attention was focused on two systems. The first would emplace a 450-m column of waste packages in predrilled holes 750 m deep. The second would use free falling gravity penetrators launched from a disposal ship to embed waste packages about 50 m below the seafloor in an array that separated each by an average of 180 m from its neighbors. Studies of each system covered all aspects, from the configuration and functions of the port facilities through transport to the ocean site, emplacement operations, and post emplacement behavior of the waste packages. Cost and reliability studies were similarly broad. ESTG concludes that viable disposal systems for subseabed emplacement of waste are feasible. If appropriate sites can be found, it appears that straightforward methods are available for producing satisfactory waste packages that can survive a 500-yr emplacement period. 172 refs., 40 figs., 19 tabs.

  15. Source team evaluation for radioactive low-level waste disposal performance assessment

    SciTech Connect

    Cowgill, M.G.; Sullivan, T.M.

    1993-01-01

    Information compiled on the low-level radioactive waste disposed at the three currently operating commercial disposal sites during the period 1987--1989 have been reviewed and processed in order to determine the total activity distribution in terms of waste stream, waste classification and waste form. The review identified deficiencies in the information currently being recorded on shipping manifests and the development of a uniform manifest is recommended (the NRC is currently developing a rule to establish a uniform manifest). The data from waste disposed during 1989 at one of the sites (Richland, WA) were more detailed than the data available during other years and at other sites, and thus were amenable to a more in-depth treatment. This included determination of the distribution of activity for each radionuclide by waste form, and thus enabled these data to be evaluated in terms of the specific needs for improved modeling of releases from waste packages. From the results, preliminary lists have been prepared of the isotopes which might be the most significant from the aspect of the development of a source term model.

  16. Historical relationship between performance assessment for radioactive waste disposal and other types of risk assessment

    SciTech Connect

    Rechard, R.P.

    1999-10-01

    This article describes the evolution of the process for assessing the hazards of a geologic disposal system for radioactive waste and, similarly, nuclear power reactors, and the relationship of this process with other assessments of risk, particularly assessments of hazards from manufactured carcinogenic chemicals during use and disposal. This perspective reviews the common history of scientific concepts for risk assessment developed until the 1950s. Computational tools and techniques developed in the late 1950s and early 1960s to analyze the reliability of nuclear weapon delivery systems were adopted in the early 1970s for probabilistic risk assessment of nuclear power reactors, a technology for which behavior was unknown. In turn, these analyses became an important foundation for performance assessment of nuclear waste disposal in the late 1970s. The evaluation of risk to human health and the environment from chemical hazards is built on methods for assessing the dose response of radionuclides in the 1950s. Despite a shared background, however, societal events, often in the form of legislation, have affected the development path for risk assessment for human health, producing dissimilarities between these risk assessments and those for nuclear facilities. An important difference is the regulator's interest in accounting for uncertainty.

  17. Multiple criteria approach to site selection of radioactive waste disposal facility in the Republic of Croatia

    SciTech Connect

    Schaller, A.; Skanata, D.

    1995-12-31

    Site selection approach to radioactive waste disposal facility, which is under way in Croatia, is presented in the paper. This approach is based on application of certain relevant terrestrial and technical criteria in the site selection process. Basic documentation used for this purpose are regional planning documents prepared by the Regional Planning Institute of Croatia. The basic result of research described in the paper is the proposal of several potential areas which are suitable for siting a radioactive waste repository. All relevant conclusions are based on both data groups -- generic and on-field experienced (measured). Out of a dozen potential areas, four have been chosen as representative by the authors. The presented comparative analysis was made by means of the VISA II computer code, developed by the V. Belton and SPV Software Products. The code was donated to the APO by the IAEA. The main objective of the paper is to initiate and facilitate further discussions on possible ways of evaluation and comparison of potential areas for sitting of radioactive waste repository in this country, as well as to provide additional contributions to the current site selection process in the Republic of Croatia.

  18. Granite disposal of U.S. high-level radioactive waste.

    SciTech Connect

    Freeze, Geoffrey A.; Mariner, Paul E.; Lee, Joon H.; Hardin, Ernest L.; Goldstein, Barry; Hansen, Francis D.; Price, Ronald H.; Lord, Anna Snider

    2011-08-01

    This report evaluates the feasibility of disposing U.S. high-level radioactive waste in granite several hundred meters below the surface of the earth. The U.S. has many granite formations with positive attributes for permanent disposal. Similar crystalline formations have been extensively studied by international programs, two of which, in Sweden and Finland, are the host rocks of submitted or imminent repository license applications. This report is enabled by the advanced work of the international community to establish functional and operational requirements for disposal of a range of waste forms in granite media. In this report we develop scoping performance analyses, based on the applicable features, events, and processes (FEPs) identified by international investigators, to support generic conclusions regarding post-closure safety. Unlike the safety analyses for disposal in salt, shale/clay, or deep boreholes, the safety analysis for a mined granite repository depends largely on waste package preservation. In crystalline rock, waste packages are preserved by the high mechanical stability of the excavations, the diffusive barrier of the buffer, and favorable chemical conditions. The buffer is preserved by low groundwater fluxes, favorable chemical conditions, backfill, and the rigid confines of the host rock. An added advantage of a mined granite repository is that waste packages would be fairly easy to retrieve, should retrievability be an important objective. The results of the safety analyses performed in this study are consistent with the results of comprehensive safety assessments performed for sites in Sweden, Finland, and Canada. They indicate that a granite repository would satisfy established safety criteria and suggest that a small number of FEPs would largely control the release and transport of radionuclides. In the event the U.S. decides to pursue a potential repository in granite, a detailed evaluation of these FEPs would be needed to inform site

  19. International program to study subseabed disposal of high-level radioactive wastes

    SciTech Connect

    Carlin, E.M.; Hinga, K.R.; Knauss, J.A.

    1984-01-01

    This report provides an overview of the international program to study seabed disposal of nuclear wastes. Its purpose is to inform legislators, other policy makers, and the general public as to the history of the program, technological requirements necessary for feasibility assessment, legal questions involved, international coordination of research, national policies, and research and development activities. Each of these major aspects of the program is presented in a separate section. The objective of seabed burial, similar to its continental counterparts, is to contain and to isolate the wastes. The subseabed option should not be confuesed with past practices of ocean dumping which have introduced wastes into ocean waters. Seabed disposal refers to the emplacement of solidified high-level radioactive waste (with or without reprocessing) in certain geologically stable sediments of the deep ocean floor. Specially designed surface ships would transport waste canisters from a port facility to the disposal site. Canisters would be buried from a few tens to a few hundreds of meters below the surface of ocean bottom sediments, and hence would not be in contact with the overlying ocean water. The concept is a multi-barrier approach for disposal. Barriers, including waste form, canister, ad deep ocean sediments, will separate wastes from the ocean environment. High-level wastes (HLW) would be stabilized by conversion into a leach-resistant solid form such as glass. This solid would be placed inside a metallic canister or other type of package which represents a second barrier. The deep ocean sediments, a third barrier, are discussed in the Feasibility Assessment section. The waste form and canister would provide a barrier for several hundred years, and the sediments would be relied upon as a barrier for thousands of years. 62 references, 3 figures, 2 tables.

  20. Proceedings of the Symposium on Uncertainties Associated with the Regulation of the Geologic Disposal of High-Level Radioactive Waste

    NASA Astrophysics Data System (ADS)

    Kocher, D. C.

    1982-03-01

    Technical aspects related to the development of standards for regulating geologic disposal of high level radioactive waste, with particular emphasis on the sources and magnitudes of uncertainties associated with methods for predicting post closure repository performance and potential health risks to future generations are discussed. Important licensing and regulatory issues involved in geologic waste disposal, and the social and political climate in which issues of high level waste management are being debated are also considered.

  1. Seal assembly

    NASA Astrophysics Data System (ADS)

    Salt, Jonathan G.; Korzun, Ronald W.; Abbott, David R.

    1993-01-01

    A unitary annular seal structure is provided for attachment to a turbine nozzle in a gas turbine engine. The nozzle includes an annular platform disposed about a longitudinal axis of the engine. An annular array of vanes is secured to the platform. The seal structure includes an abradable annular seal member, a seal backing member, and a seal attachment ring. The ring includes an annular, radially extending, axially acting spring member positioned to cooperate with a plurality of radially extending tabs on the backing member. In use, the seal structure is positioned within a circular opening within the turbine nozzle. The nozzle includes a radially depending appendage formed as part of the nozzle platform. The spring member abuts one side of the appendage and the tabs are positioned to abut another side of the appendage for holding the annular spring member in gas sealing engagement with the appendage to thus provide a seal against gas leakage and to restrain the seal structure axially. The spring member and tabs comprise a radially slideable joint for the seal structure. To restrict circumferential motion of the structure, slots are formed in the appendage for receiving the tabs. The seal is easily replaced by bending the tabs and sliding the seal structure axially out of the nozzle. Differential thermal expansion is accommodated by the slideable seal arrangement.

  2. Geotechnical, geological, and selected radionuclide retention characteristics of the radioactive waste disposal site near the Farallon Islands

    USGS Publications Warehouse

    Booth, J.S.; Winters, W.J.; Poppe, L.J.; Neiheisel, J.; Dyer, R.S.

    1989-01-01

    A geotechnical and geological investigation of the Farallon Islands low-level radioactive waste (LLW) disposal area was conducted to qualitatively assess the host sediments' relative effectiveness as a barrier to radionuclide migration, to estimate the portion of the barrier that is in contact with the waste packages at the three primary disposal sites, and to provide a basic physical description of the sediments. Box cores recovered from within the general disposal area at depths of 500, 1000, and 1500 m were subcored to provide samples (~30 cm in length) for detailed descriptions, textural and mineralogical analyses, and a suite of geotechnical tests (index property, CRS consolidation, and CIU triaxial compression). -from Authors

  3. Performance assessment handbook for low-level radioactive waste disposal facilities

    SciTech Connect

    Seitz, R.R.; Garcia, R.S.; Kostelnik, K.M.; Starmer, R.J.

    1992-02-01

    Performance assessments of proposed low-level radioactive waste disposal facilities must be conducted to support licensing. This handbook provides a reference document that can be used as a resource by management and staff responsible for performance assessments. Brief discussions describe the performance assessment process and emphasize selected critical aspects of the process. References are also provided for additional information on many aspects of the performance assessment process. The user's manual for the National Low-Level Waste Management Program's Performance Assessment Center (PAC) on the Idaho National Engineering Laboratory Cray computer is included as Appendix A. The PAC provides users an opportunity to experiment with a number of performance assessment computer codes on a Cray computer. Appendix B describes input data required for 22 performance assessment codes.

  4. Model training curriculum for Low-Level Radioactive Waste Disposal Facility Operations

    SciTech Connect

    Tyner, C.J.; Birk, S.M.

    1995-09-01

    This document is to assist in the development of the training programs required to be in place for the operating license for a low-level radioactive waste disposal facility. It consists of an introductory document and four additional appendixes of individual training program curricula. This information will provide the starting point for the more detailed facility-specific training programs that will be developed as the facility hires and trains new personnel and begins operation. This document is comprehensive and is intended as a guide for the development of a company- or facility-specific program. The individual licensee does not need to use this model training curriculum as written. Instead, this document can be used as a menu for the development, modification, or verification of customized training programs.

  5. Trees as indicators of subterranean water flow from a retired radioactive waste disposal site.

    PubMed

    Rickard, W H; Kirby, L J

    1987-02-01

    Tree sampling helped locate a subterranean flow of tritiated water from a low-level radioactive waste disposal site that had not been detected by well water monitoring alone. Deciduous trees growing in a natural forest on the hillsides downslope from the site were sampled for the presence of tritiated water in sap of maple trees and in leaf water extracted from oak and hickory trees. Elevated concentrations of 3H were detected in the leaf water extracted from several trees located 50 m downslope from the western boundary of the fenced exclusion zone. A 3-m-deep well drilled near these trees indicated that the source of tritiated water was a narrow zone of subterranean flow. PMID:3818287

  6. Comparative approaches to siting low-level radioactive waste disposal facilities

    SciTech Connect

    Newberry, W.F.

    1994-07-01

    This report describes activities in nine States to select site locations for new disposal facilities for low-level radioactive waste. These nine States have completed processes leading to identification of specific site locations for onsite investigations. For each State, the status, legal and regulatory framework, site criteria, and site selection process are described. In most cases, States and compact regions decided to assign responsibility for site selection to agencies of government and to use top-down mapping methods for site selection. The report discusses quantitative and qualitative techniques used in applying top-down screenings, various approaches for delineating units of land for comparison, issues involved in excluding land from further consideration, and different positions taken by the siting organizations in considering public acceptance, land use, and land availability as factors in site selection.

  7. Perspectives on Radioactive Waste Disposal: A Consideration of Economic Efficiency and Intergenerational Equity

    SciTech Connect

    Neill, H. R.; Neill, R. H.

    2003-02-25

    There are both internal and external pressures on the U.S. Department of Energy to reduce the estimated costs of isolating radioactive waste, $19 billion for transuranic waste at Waste Isolation Pilot Plant (WIPP) and $57 billion for high level waste at Yucca Mountain. The question arises whether economic analyses would add to the decision-making process to reduce costs yet maintain the same level of radiological protection. This paper examines the advantages and disadvantages of using cost-benefit analysis (CBA), a tool used to measure economic efficiency as an input for these decisions. Using a comparative research approach, we find that CBA analyses appear particularly applicable where the benefits and costs are in the near term. These findings can help policymakers become more informed on funding decisions and to develop public confidence in the merits of the program for waste disposal.

  8. Disposing of High-Level Radioactive Waste in Germany - A Note from the Licensing Authority - 12530

    SciTech Connect

    Pick, Thomas Stefan; Bluth, Joachim; Lauenstein, Christof; Markhoefer, Joerg

    2012-07-01

    Following the national German consensus on the termination of utilisation of nuclear energy in the summer of 2011, the Federal and Laender Governments have declared their intention to work together on a national consensus on the disposal of radioactive waste as well. Projected in the early 1970's the Federal Government had started exploring the possibility to establish a repository for HLW at the Gorleben site in 1977. However, there is still no repository available in Germany today. The delay results mainly from the national conflict over the suitability of the designated Gorleben site, considerably disrupting German society along the crevice that runs between supporters and opponents of nuclear energy. The Gorleben salt dome is situated in Lower Saxony, the German state that also hosts the infamous Asse mine repository for LLW and ILW and the Konrad repository project designated to receive LLW and ILW as well. With the fourth German project, the Morsleben L/ILW repository only 20 km away across the state border, the state of Lower Saxony carries the main load for the disposal of radioactive waste in Germany. After more than 25 years of exploration and a 10 year moratorium the Gorleben project has now reached a cross-road. Current plans for setting up a new site selection procedure in Germany call for the selection and exploration of up to four alternative sites, depending only on suitable geology. In the meantime the discussion is still open on whether the Gorleben project should be terminated in order to pacify the societal conflict or being kept in the selection process on account of its promising geology. The Lower Saxony Ministry for Environment and Climate Protection proposes to follow a twelve-step-program for finding the appropriate site, including the Gorleben site in the process. With its long history of exploration the site is the benchmark that alternative sites will have to compare with. Following the national consensus of 2011 on the termination of

  9. Radioactive Solid Waste Storage and Disposal at Oak Ridge National Laboratory, Description and Safety Analysis

    SciTech Connect

    Bates, L.D.

    2001-01-30

    Oak Ridge National Laboratory (ORNL) is a principle Department of Energy (DOE) Research Institution operated by the Union Carbide Corporation - Nuclear Division (UCC-ND) under direction of the DOE Oak Ridge Operations Office (DOE-ORO). The Laboratory was established in east Tennessee, near what is now the city of Oak Ridge, in the mid 1940s as a part of the World War II effort to develop a nuclear weapon. Since its inception, disposal of radioactively contaminated materials, both solid and liquid, has been an integral part of Laboratory operations. The purpose of this document is to provide a detailed description of the ORNL Solid Waste Storage Areas, to describe the practice and procedure of their operation, and to address the health and safety impacts and concerns of that operation.

  10. A Probabilistic Performance Assessment Study of Potential Low-Level Radioactive Waste Disposal Sites in Taiwan

    NASA Astrophysics Data System (ADS)

    Knowlton, R. G.; Arnold, B. W.; Mattie, P. D.; Kuo, M.; Tien, N.

    2006-12-01

    For several years now, Taiwan has been engaged in a process to select a low-level radioactive waste (LLW) disposal site. Taiwan is generating LLW from operational and decommissioning wastes associated with nuclear power reactors, as well as research, industrial, and medical radioactive wastes. The preliminary selection process has narrowed the search to four potential candidate sites. These sites are to be evaluated in a performance assessment analysis to determine the likelihood of meeting the regulatory criteria for disposal. Sandia National Laboratories and Taiwan's Institute of Nuclear Energy Research have been working together to develop the necessary performance assessment methodology and associated computer models to perform these analyses. The methodology utilizes both deterministic (e.g., single run) and probabilistic (e.g., multiple statistical realizations) analyses to achieve the goals. The probabilistic approach provides a means of quantitatively evaluating uncertainty in the model predictions and a more robust basis for performing sensitivity analyses to better understand what is driving the dose predictions from the models. Two types of disposal configurations are under consideration: a shallow land burial concept and a cavern disposal concept. The shallow land burial option includes a protective cover to limit infiltration potential to the waste. Both conceptual designs call for the disposal of 55 gallon waste drums within concrete lined trenches or tunnels, and backfilled with grout. Waste emplaced in the drums may be solidified. Both types of sites are underlain or placed within saturated fractured bedrock material. These factors have influenced the conceptual model development of each site, as well as the selection of the models to employ for the performance assessment analyses. Several existing codes were integrated in order to facilitate a comprehensive performance assessment methodology to evaluate the potential disposal sites. First, a need

  11. Modeling Groundwater Flow and Infiltration at Potential Low-Level Radioactive Waste Disposal Sites in Taiwan

    NASA Astrophysics Data System (ADS)

    Arnold, B. W.; Lee, C.; Ma, C.; Knowlton, R. G.

    2006-12-01

    Taiwan is evaluating representative sites for the potential disposal of low-level radioactive waste (LLW), including consideration of shallow land burial and cavern disposal concepts. A representative site for shallow land burial is on a small island in the Taiwan Strait with basalt bedrock. The shallow land burial concept includes an engineered cover to limit infiltration into the waste disposal cell. A representative site for cavern disposal is located on the southeast coast of Taiwan. The tunnel system for this disposal concept would be several hundred meters below the mountainous land surface in argillite bedrock. The LLW will consist of about 966,000 drums, primarily from the operation and decommissioning of four nuclear power plants. Sandia National Laboratories and the Institute of Nuclear Energy Research have collaborated to develop performance assessment models to evaluate the long-term safety of LLW disposal at these representative sites. Important components of the system models are sub-models of groundwater flow in the natural system and infiltration through the engineered cover for the shallow land burial concept. The FEHM software code was used to simulate groundwater flow in three-dimensional models at both sites. In addition, a higher-resolution two-dimensional model was developed to simulate flow through the engineered tunnel system at the cavern site. The HELP software was used to simulate infiltration through the cover at the island site. The primary objective of these preliminary models is to provide a modeling framework, given the lack of site-specific data and detailed engineering design specifications. The steady-state groundwater flow model at the island site uses a specified recharge boundary at the land surface and specified head at the island shoreline. Simulated groundwater flow vectors are extracted from the FEHM model along a cross section through one of the LLW disposal cells for utilization in radionuclide transport simulations in

  12. Radionuclide concentrations in vegetation at radioactive-waste disposal Area G during the 1994 growing season

    SciTech Connect

    Fresquez, P.R.; Biggs, J.B.; Bennett, K.D.

    1995-07-01

    Overstory (pinon pine) and understory (grass and forb) vegetation samples were collected within and around selected points at Area G-a low-level radioactive solid-waste disposal facility at Los Alamos National Laboratory-for the analysis of tritium ({sup 3}H), strontium ({sup 90}Sr), plutonium ({sup 238} Pu and {sup 239}Pu), cesium ({sup 137}Cs), americium ({sup 241}Am), and total uranium. In general, most vegetation samples collected within and around Area G contained radionuclide levels in higher concentrations than vegetation collected from background areas. Tritium, in particular, was detected as high as 5,800 pCi/mL in overstory vegetation collected outside the fence just west of the tritium shafts; this suggests that tritium is migrating from this waste repository through subsurface pathways. Also, understory vegetation collected north of the transuranic (TRU) pads (outside the fence of Area G) contained the highest values of {sup 90}Sr, {sup 238}Pu, {sup 239}Pu, {sup 137}Cs, and {sup 241}Am, and may be a result of surface holding, storage, or disposal activities.

  13. Survey of degradation modes of candidate materials for high-level radioactive-waste disposal containers

    SciTech Connect

    Bullen, D.B.; Gdowski, G.E. ); Weiss, H. )

    1988-06-01

    Three copper-based alloys, CDA 102 (oxygen-free copper), CDA 613 (Cu-7Al), and CDA 715 (Cu-30Ni), are being considered along with three austenitic candidates as possible materials for fabrication of containers for disposal of high-level radioactive waste. The waste will include spent fuel assemblies from reactors as well as high-level reprocessing wastes in borosilicate glass and will be sent to the prospective repository at Yucca Mountain, Nevada, for disposal. The containers must maintain mechanical integrity for 50 yr after emplacement to allow for retrieval of waste during the preclosure phase of repository operation. Containment is required to be substantially complete for up to 300 to 1000 yr. During the early period, the containers will be exposed to high temperatures and high gamma radiation fields from the decay of high-level waste. The final closure joint will be critical to the integrity of the containers. This volume surveys the available data on the metallurgy of the copper-based candidate alloys and the welding techniques employed to join these materials. The focus of this volume is on the methods applicable to remote-handling procedures in a hot-cell environment with limited possibility of postweld heat treatment. The three copper-based candidates are ranked on the basis of the various closure techniques. On the basis of considerations regarding welding, the following ranking is proposed for the copper-based alloys: CDA 715 (best) > CDA 102 > CDA 613 (worst). 49 refs., 15 figs., 1 tab.

  14. The application of magnetic gradiometry and electromagnetic induction at a former radioactive waste disposal site.

    PubMed

    Rucker, Dale Franklin

    2010-04-01

    A former radioactive waste disposal site is surveyed with two non-intrusive geophysical techniques, including magnetic gradiometry and electromagnetic induction. Data were gathered over the site by towing the geophysical equipment mounted to a non-electrically conductive and non-magnetic fibre-glass cart. Magnetic gradiometry, which detects the location of ferromagnetic material, including iron and steel, was used to map the existence of a previously unknown buried pipeline formerly used in the delivery of liquid waste to a number of surface disposal trenches and concrete vaults. The existence of a possible pipeline is reinforced by historical engineering drawing and photographs. The electromagnetic induction (EMI) technique was used to map areas of high and low electrical conductivity, which coincide with the magnetic gradiometry data. The EMI also provided information on areas of high electrical conductivity unrelated to a pipeline network. Both data sets demonstrate the usefulness of surface geophysical surveillance techniques to minimize the risk of exposure in the event of future remediation efforts. PMID:20124318

  15. Solution speciation of plutonium and Americium at an Australian legacy radioactive waste disposal site.

    PubMed

    Ikeda-Ohno, Atsushi; Harrison, Jennifer J; Thiruvoth, Sangeeth; Wilsher, Kerry; Wong, Henri K Y; Johansen, Mathew P; Waite, T David; Payne, Timothy E

    2014-09-01

    During the 1960s, radioactive waste containing small amounts of plutonium (Pu) and americium (Am) was disposed in shallow trenches at the Little Forest Burial Ground (LFBG), located near the southern suburbs of Sydney, Australia. Because of periodic saturation and overflowing of the former disposal trenches, Pu and Am have been transferred from the buried wastes into the surrounding surface soils. The presence of readily detected amounts of Pu and Am in the trench waters provides a unique opportunity to study their aqueous speciation under environmentally relevant conditions. This study aims to comprehensively investigate the chemical speciation of Pu and Am in the trench water by combining fluoride coprecipitation, solvent extraction, particle size fractionation, and thermochemical modeling. The predominant oxidation states of dissolved Pu and Am species were found to be Pu(IV) and Am(III), and large proportions of both actinides (Pu, 97.7%; Am, 86.8%) were associated with mobile colloids in the submicron size range. On the basis of this information, possible management options are assessed. PMID:25126837

  16. Unsaturated flow modeling for performance assessment of a radioactive waste disposal facility in Andrews County, Texas

    NASA Astrophysics Data System (ADS)

    Martinez Baquero, G. F.; Singh, A.; Holt, R. M.; grisak, G. E.

    2011-12-01

    Quantitifying infiltration rates is a key component of the performance assessment for radioactive waste disposal facilities. In arid regions with scarce infiltration data, this is a challenging problem because of the computational limitations of available numerical implementations to solve water flow and transport equations. This work summarizes methodology and analysis performed to overcome some of these challenges and to generate infiltration scenarios for a low level waste disposal site in Andrews County, Texas. The work presented here includes preparation of a two dimensional finite element model in HYDRUS that includes the cover system and adjacent geologic units, calibration of hydraulic properties and root water uptake parameters based on soft information, preparation of atmospheric forcings based on current and hypothesized future climatic conditions, evaluation of impacts related to temporal and spatial discretization of forcings and model domain, and definition of scenarios for cover degradation and wetter climate conditions. Results of this work include a sensitivity analysis of infiltration rates to changes in boundary conditions under quasi-steady state, evaluation of the impact of temporal discretization of the atmospheric forcings in terms of water balance error and computational efficiency, and the estimation of infiltration rates under different scenarios. Infiltration rates from this work are being incorporated into a transport model to estimate potential radiological doses based on performance assessment modeling analyses. Findings from this work seek to contribute towards robust approaches to estimate infiltration in arid regions.

  17. Importance of geologic characterization of potential low-level radioactive waste disposal sites

    USGS Publications Warehouse

    Weibel, C.P.; Berg, R.C.

    1991-01-01

    Using the example of the Geff Alternative Site in Wayne County, Illinois, for the disposal of low-level radioactive waste, this paper demonstrates, from a policy and public opinion perspective, the importance of accurately determining site stratigraphy. Complete and accurate characterization of geologic materials and determination of site stratigraphy at potential low-level waste disposal sites provides the frame-work for subsequent hydrologic and geochemical investigations. Proper geologic characterization is critical to determine the long-term site stability and the extent of interactions of groundwater between the site and its surroundings. Failure to adequately characterize site stratigraphy can lead to the incorrect evaluation of the geology of a site, which in turn may result in a lack of public confidence. A potential problem of lack of public confidence was alleviated as a result of the resolution and proper definition of the Geff Alternative Site stratigraphy. The integrity of the investigation was not questioned and public perception was not compromised. ?? 1991 Springer-Verlag New York Inc.

  18. Centrifuge modeling of radioactive waste migration through backfill in a near surface disposal facility

    SciTech Connect

    Gurumoorthy, C.; Kusakabe, O.

    2007-07-01

    Investigations on the performance of backfill barrier in Near Surface Disposal Facility (NSDF) for radioactive wastes are important to ensure the long term safety of such disposal option. Favorable condition to delay migration of radionuclides from disposed waste to far fields is diffusion process. However, advective dispersion/diffusion mechanism plays an important role due to changes in backfill over a period of time. In order to understand these mechanisms, detailed laboratory experiments are usually conducted for developing mathematical models to assess the behaviour of backfill. However, these experiments are time consuming and suffer with the limitations due to material complexity. Also, there are constraints associated with validation of theoretical predictions due to intricacy of boundary conditions as well as the time scale is quite different as compared to the time required for completion of the processes in the field. Keeping in view these aspects, centrifuge modeling technique has been adopted by various researchers to model and understand various geo-environment problems in order to provide a link between the real life situation termed as the 'Prototype' and its model, which is exposed to a higher gravitational field. An attempt has been made in this paper to investigate the feasibility of this technique to model advective dispersion/diffusion mechanism of radionuclides through saturated Bentonite-Sand (B:S) backfill. Various stages of centrifuge modeling are highlighted. Column tests were conducted in the centrifuge to evaluate the hydraulic conductivity of B:S mixture under prototype NSDF stress conditions. Results showed that steady state hydraulic conductivity under saturated conditions was 2.86 10{sup -11} m/sec. Studies indicate the feasibility of centrifuge modeling technique and usefulness to model advective diffusion of radionuclides through B:S backfill. (authors)

  19. Tectonic and climatic considerations for deep geological disposal of radioactive waste: A UK perspective.

    PubMed

    McEvoy, F M; Schofield, D I; Shaw, R P; Norris, S

    2016-11-15

    Identifying and evaluating the factors that might impact on the long-term integrity of a deep Geological Disposal Facility (GDF) and its surrounding geological and surface environment is central to developing a safety case for underground disposal of radioactive waste. The geological environment should be relatively stable and its behaviour adequately predictable so that scientifically sound evaluations of the long-term radiological safety of a GDF can be made. In considering this, it is necessary to take into account natural processes that could affect a GDF or modify its geological environment up to 1millionyears into the future. Key processes considered in this paper include those which result from plate tectonics, such as seismicity and volcanism, as well as climate-related processes, such as erosion, uplift and the effects of glaciation. Understanding the inherent variability of process rates, critical thresholds and likely potential influence of unpredictable perturbations represent significant challenges to predicting the natural environment. From a plate-tectonic perspective, a one million year time frame represents a very short segment of geological time and is largely below the current resolution of observation of past processes. Similarly, predicting climate system evolution on such time-scales, particularly beyond 200ka AP is highly uncertain, relying on estimating the extremes within which climate and related processes may vary with reasonable confidence. The paper highlights some of the challenges facing a deep geological disposal program in the UK to review understanding of the natural changes that may affect siting and design of a GDF. PMID:27457674

  20. Survey of degradation modes of candidate materials for high-level radioactive-waste disposal containers

    SciTech Connect

    Gdowski, G.E.; Bullen, D.B. )

    1988-08-01

    Three copper-based alloys and three iron- to nickel-based austenitic alloys are being considered as possible materials for fabrication of containers for disposal of high-level radioactive waste. This waste will include spent fuel assemblies from reactors as well as high-level waste in borosilicate glass and will be sent to the prospective site at Yucca Mountain, Nevada, for disposal. The containers must maintain substantially complete containment for at least 300 yr and perhaps as long as 1000 yr. During the first 50 yr after emplacement, they must be retrievable from the disposal site. Shortly after the containers are emplaced in the repository, they will be exposed to high temperatures and high gamma radiation fields from the decay of the high-level waste. This volume surveys the available data on oxidation and corrosion of the iron- to nickel-based austenitic materials (Types 304L and 316L stainless steels and Alloy 825) and the copper-based alloy materials (CDA 102 (oxygen-free copper), CDA 613 (Cu-7Al), and CDA 715 (Cu-30Ni)), which are the present candidates for fabrication of the containers. Studies that provided a large amount of data are highlighted, and those areas in which little data exists are identified. Examples of successful applications of these materials are given. On the basis of resistance to oxidation and general corrosion, the austenitic materials are ranked as follows: Alloy 825 (best), Type 316L stainless steel, and then Type 304L stainless steel (worst). For the copper-based materials, the ranking is as follows: CDA 715 and CDA 613 (both best), and CDA 102 (worst). 110 refs., 30 figs., 13 tabs.

  1. Survey of degradation modes of candidate materials for high-level radioactive-waste disposal containers

    SciTech Connect

    Bullen, D.B.; Gdowski, G.E. )

    1988-08-01

    Three copper-based alloys and three iron- to nickel-based austenitic alloys are being considered as possible materials for fabrication of high-level radioactive-waste disposal containers. The waste will include spent fuel assemblies from reactors as well as high-level waste in borosilicate glass and will be sent to the prospective site at Yucca Mountain, Nevada, for disposal. The copper-based alloy materials are CDA 102 (oxygen-free copper), CDA 613 (Cu-7Al), and CDA 715 (Cu-30Ni). The austenitic materials are Types 304L and 316L stainless steels and Alloy 825. The waste-package containers must maintain substantially complete containment for at least 300 yr and perhaps as long as 1000 yr, and they must be retrievable from the disposal site during the first 50 yr after emplacement. The containers will be exposed to high temperatures and high gamma radiation fields from the decay of high-level waste. This volume surveys the available data on the phase stability of both groups of candidate alloys. The austenitic alloys are reviewed in terms of the physical metallurgy of the iron-chromium-nickel system, martensite transformations, carbide formation, and intermetallic-phase precipitation. The copper-based alloys are reviewed in terms of their phase equilibria and the possibility of precipitation of the minor alloying constituents. For the austenitic materials, the ranking based on phase stability is: Alloy 825 (best), Type 316L stainless steel, and then Type 304L stainless steel (worst). For the copper-based materials, the ranking is: CDA 102 (oxygen-free copper) (best), and then both CDA 715 and CDA 613. 75 refs., 24 figs., 6 tabs.

  2. Considerations of human inturison in U.S. programs for deep geologic disposal of radioactive waste.

    SciTech Connect

    Swift, Peter N.

    2013-01-01

    Regulations in the United States that govern the permanent disposal of spent nuclear fuel and high-level radioactive waste in deep geologic repositories require the explicit consideration of hypothetical future human intrusions that disrupt the waste. Specific regulatory requirements regarding the consideration of human intrusion differ in the two sets of regulations currently in effect in the United States; one defined by the Environmental Protection Agency's 40 Code of Federal Regulations part 197, applied only to the formerly proposed geologic repository at Yucca Mountain, Nevada, and the other defined by the Environmental Protection Agency's 40 Code of Federal Regulations part 191, applied to the Waste Isolation Pilot Plant in New Mexico and potentially applicable to any repository for spent nuclear fuel and high-level radioactive waste in the United States other than the proposed repository at Yucca Mountain. This report reviews the regulatory requirements relevant to human intrusion and the approaches taken by the Department of Energy to demonstrating compliance with those requirements.

  3. Introduction to Special Section on Geophysical Investigations of Proposed Radioactive Waste Disposal Sites

    NASA Astrophysics Data System (ADS)

    Oliver, H. W.

    1987-07-01

    A symposium on "Geophysical Investigations of Proposed Radioactive Waste Disposal Sites" was held at the Fall Meeting of the American Geophysical Union, December 13, 1982. Since then, five of the papers presented at the symposium have been published in the Journal of Geophysical Research and an additional six papers are included in this issue. Three of the current papers involve geophysical research at Yucca Mountain, Nevada; two papers are on subsurface structure and fracturing of the Strath-Halladale granite in northern Scotland, a prime candidate for rad waste storage in the United Kingdom; and a general paper is included on the application of various geophysical methods for characterizing all the potential storage sites in the United States under consideration by the U.S. Department of Energy. In 1982, the following nine sites in the United States (Figure 1) were under consideration by the U.S. Department of Energy for the first U.S. repository of high-level radioactive waste (HLW). The host rock at each site is noted in parentheses (from NW to SE): Hanford, Washington (Miocene basalt flows); Yucca Mountain, Nevada (Tertiary tuff); Davis Canyon, Utah, (bedded salt); Lavender Canyon, Utah (bedded salt); Deaf Smith, Texas (Permian bedded salt); Swisher County, Texas (Permian bedded salt); Vacherie dome, Louisiana (domal salt); Richton dome, Mississippi (domal salt); and Cypress Creek dome, Mississippi (domal salt)

  4. SAMPLING THE OCEANS FOR POLLUTION: A RISK ASSESSMENT APPROACH TO EVALUATING LOW-LEVEL RADIOACTIVE WASTE DISPOSAL AT SEA

    EPA Science Inventory

    A protocol for licensing disposal of low-level radioactive wastes in the deep ocean is proposed. It is based on principles of risk assessment. Assessments of waste characteristics and site characteristics are integrated to predict an exposure field within which concentrations of ...

  5. Nozzle seal

    DOEpatents

    Herman, Richard Frederick

    1977-10-25

    In an illustrative embodiment of the invention, a nuclear reactor pressure vessel, having an internal hoop from which the heated coolant emerges from the reactor core and passes through to the reactor outlet nozzles, is provided with sealing members operatively disposed between the outlet nozzle and the hoop. The sealing members are biased against the pressure vessel and the hoop and are connected by a leak restraining member establishing a leak-proof condition between the inlet and outlet coolants in the region about the outlet nozzle. Furthermore, the flexible responsiveness of the seal assures that the seal will not structurally couple the hoop to the pressure vessel.

  6. Linkage Between Post-Closure Safety Case Review and the Authorization Process for Radioactive Waste Disposal Facilities

    SciTech Connect

    Streatfield, I. J.; Duerden, S. L.; Yearsley, R. A.; Bennett, D. G.

    2003-02-27

    The Environment Agency (the Agency) has responsibilities under the Radioactive Substances Act of 1993 for regulating the disposal and storage of radioactive wastes in England and Wales, including regulation of the disposal site for UK solid low-level waste (LLW) at Drigg in Cumbria, NW England. To help inform the next review of the Drigg disposal authorization, the Agency has required the operator, British Nuclear Fuels plc to submit a Post-Closure Safety Case which will assess the potential long-term impacts from the site. With the aim of using best practice to determine authorization conditions, the Agency contracted Galson Sciences, Ltd to undertake an international survey of authorization procedures for comparable facilities in other countries. This paper provides an overview of the findings from the international survey.

  7. Durability of a reinforced concrete designed for the construction of an intermediate-level radioactive waste disposal facility

    NASA Astrophysics Data System (ADS)

    Duffó, G. S.; Arva, E. A.; Schulz, F. M.; Vazquez, D. R.

    2012-01-01

    The National Atomic Energy Commission of the Argentine Republic is developing a nuclear waste disposal management programme that contemplates the design and construction of a facility for the final disposal of intermediate-level radioactive wastes. The repository is based on the use of multiple, independent and redundant barriers. The major components are made in reinforced concrete so, the durability of these structures is an important aspect for the facility integrity. This work presents an investigation performed on a reinforced concrete specifically designed for this purpose, to predict the service life of the intermediate level radioactive waste disposal facility from data obtained with several techniques. Results obtained with corrosion sensors embedded in a concrete prototype are also included. The information obtained will be used for the final design of the facility in order to guarantee a service life more or equal than the foreseen durability for this type of facilities.

  8. Intended long term performances of cementitious engineered barriers for future storage and disposal facilities for radioactive wastes in Romania

    NASA Astrophysics Data System (ADS)

    Fako, R.; Barariu, Gh.; Toma, R.; Georgescu, R.; Sociu, F.

    2013-07-01

    Considering the EU statements, Romania is engaged to endorse in the near future the IAEA relevant publications on geological repository (CNCANa), to update the Medium and Long Term National Strategy for Safe Management of Radioactive Waste and to approve the Road Map for Geological Repository Development. Currently, for example, spent fuel is wet stored for 6 years and after this period it is transported to dry storage in MACSTOR-200 (a concrete monolithic module) where it is intended to remain at least 50 years. The present situation for radioactive waste management in Romania is reviewed in the present paper. Focus will be done on existent disposal facilities but, also, on future facilities planned for storage / disposal of radioactive wastes. Considering specific data for Romanian radioactive waste inventory, authors are reviewing the advance in the radioactive waste management in Romania considering its particularities. The team tries to highlight the expected limitations and unknown data related with cementitious engineered barriers that has to be faced in the near future incase of interim storage or for the upcoming long periods of disposal.

  9. Characterization of Greater-Than-Class C sealed sources. Volume 1, Sealed sources held by specific licensees

    SciTech Connect

    Harris, G.

    1994-09-01

    Sealed sources are small, relatively high-activity radioactive sources typically encapsulated in a metallic container. The activities can range from less than 1 mCi to over 1,000 Ci. They are used in a variety of industries and are commonly available. Many of the sources will be classified as Greater-Than-Class C low-level radioactive waste (GTCC LLW) for the purpose of waste disposal. The US Department of Energy is responsible for disposing of this class of low-level radioactive waste. To better understand the scope of the GTCC LLW situation regarding sealed sources and to provide data to a model that projects future quantities of GTCC material, data from a comprehensive 1991 US Nuclear Regulatory Commission (NRC) survey and a related 1992 survey of Agreement States were analyzed to estimate the number, volume, and activity of Potential GTCC sealed sources currently available from specific licensees. Potential GTCC sealed sources are sources that exceed the limits stated in 10 CFR 61 when isotope concentrations are averaged over the volume of the capsule. Based on the surveys, the estimated number of existing Potential GTCC sealed sources held by specific licensees is 89,000, with an unpackaged volume of 0.93 m{sup 3} and an activity of 2,300,000 Ci. However, current disposal practices allow concentration averaging over the disposal container, substantially reducing the number of sealed sources which will actually be classified as GTCC LLW.

  10. Seal assembly

    SciTech Connect

    Johnson, Roger Neal; Longfritz, William David

    2001-01-01

    A seal assembly that seals a gap formed by a groove comprises a seal body, a biasing element, and a connection that connects the seal body to the biasing element to form the seal assembly. The seal assembly further comprises a concave-shaped center section and convex-shaped contact portions at each end of the seal body. The biasing element is formed from an elastic material and comprises a convex-shaped center section and concave-shaped biasing zones that are opposed to the convex-shaped contact portions. The biasing element is adapted to be compressed to change a width of the seal assembly from a first width to a second width that is smaller than the first width. In the compressed state, the seal assembly can be disposed in the groove. After release of the compressing force, the seal assembly expands. The contact portions will move toward a surface of the groove and the biasing zones will move into contact with another surface of the groove. The biasing zones will bias the contact portions of the seal body against the surface of the groove.

  11. A review of geoscience characteristics and disposal experience at the commercial low-level radioactive waste disposal facility near West Valley, New York

    SciTech Connect

    Smoot, J.L.

    1989-08-01

    The West Valley Commercial Low-Level Radioactive Waste disposal site is located about 48 km south of Buffalo, New York. Operation of the site began in 1961 by Nuclear Fuels Service and was terminated in 1975. The disposal trenches at the site are excavated about 5 m into glacial till that has a thickness of about 28 m. About 65,000 m{sup 3} of the waste containing approximately 710,000 Ci were disposed at the site during the operational period. Ground-water movement through the till is predominantly downward as indicated by measurements and numerical simulation of hydraulic head. Radionuclides do not appear to have migrated more than 3 m either laterally or vertically from the waste disposal trenches. Numerical simulations of {sup 3}H, {sup 90}Sr, and {sup 14}C migration are able to reproduce the observed concentration in the till beneath selected trenches. Uncertainty remains with respect to the continuity and heterogeneity of the hydrostratigraphic units and the spatial distribution of hydraulic conductivity and effective porosity. More work is needed to better define the waste inventory and any long-term changes that might be expected. Erosion poses a potential threat to the long-term integrity of the disposal area. 56 refs., 19 figs., 9 tabs.

  12. Using performance assessment for radioactive waste disposal decision making -- implementation of the methodology into the third performance assessment iteration of the Greater Confinement Disposal site

    SciTech Connect

    Gallegos, D.P.; Conrad, S.H.; Baer, T.A.

    1993-12-31

    The US Department of Energy is responsible for the disposal of a variety of radioactive wastes. Some of these wastes are prohibited from shallow land burial and also do not meet the waste acceptance criteria for proposed waste repositories at the Waste Isolation Pilot Plant (WIPP) and Yucca Mountain. These have been termed ``special-case`` waste and require an alternative disposal method. From 1984 to 1989, the Department of Energy disposed of a small quantity of special-case transuranic wastes at the Greater Confinement Disposal (GCD) site at the Nevada Test Site. In this paper, an iterative performance assessment is demonstrated as a useful decision making tool in the overall compliance assessment process for waste disposal. The GCD site has been used as the real-site implementation and test of the performance assessment approach. Through the first two performance assessment iterations for the GCD site, and the transition into the third, we demonstrate how the performance assessment methodology uses probabilistic risk concepts to guide affective decisions about site characterization activities and how it can be used as a powerful tool in bringing compliance decisions to closure.

  13. Hydrogeologic factors in the selection of shallow land burial sites for the disposal of low-level radioactive waste

    USGS Publications Warehouse

    Fischer, John N.

    1986-01-01

    In the United States, low-level radioactive waste is disposed of by shallow land burial. Commercial low-level radioactive waste has been buried at six sites, and low-level radioactive waste generated by the Federal Government has been buried at nine major and several minor sites. Several existing low-level radioactive waste sites have not provided expected protection of the environment. These shortcomings are related, at least in part, to an inadequate understanding of site hydrogeology at the time the sites were selected. To better understand the natural systems and the effect of hydrogeologic factors on long-term site performance, the U.S. Geological Survey has conducted investigations at five of the six commercial low-level radioactive waste sites and at three Federal sites. These studies, combined with those of other Federal and State agencies, have identified and confirmed important hydrogeologic factors in the effective disposal of low-level radioactive waste by shallow land burial. These factors include precipitation, surface drainage, topography, site stability, geology, thickness of the host soil-rock horizon, soil and sediment permeability, soil and water chemistry, and depth to the water table.

  14. Nozzle seal

    DOEpatents

    Groff, Russell Dennis; Vatovec, Richard John

    1978-06-11

    In an illustrative embodiment of the invention, a nuclear reactor pressure vessel, having an internal hoop from which the heated coolant emerges from the reactor core and passes through to the reactor outlet nozzles, is provided with annular sealing members operatively disposed between the outlet nozzle and the hoop and partly within a retaining annulus formed in the hoop. The sealing members are biased against the pressure vessel and the hoop and one of the sealing members is provided with a piston type pressure ring sealing member which effectively closes the path between the inlet and outlet coolants in the region about the outlet nozzle establishing a leak-proof condition. Furthermore, the flexible responsiveness of the seal assures that the seal will not structurally couple the hoop to the pressure vessel.

  15. A review of approaches for communicating uncertainty in radioactive waste disposal programmes

    NASA Astrophysics Data System (ADS)

    McEvoy, Fiona; West, Julie; Bloodworth, Andrew

    2014-05-01

    The technical safety case for a geological repository is based in part on assessments of long-term future behaviour. Technical specialists are required to provide evidence to the greatest extent possible that the predictions are sufficiently reliable for the purpose of making the safety case. This process involves comparison of modelling results with laboratory and field results and with observations on natural and man-made analogue systems. A collection of arguments and evidence are required to help establish the basis for the safety of the repository, as well as to help reduce uncertainty and develop confidence in the analyses themselves. The safety case prepared for a proposed repository must be understood by regulators responsible for scrutinising and judging its acceptability. For the general public, however, it is difficult to make all of the arguments sufficiently transparent and understandable to ensure they share the same level of confidence as the technical specialists. A large body of qualified knowledge resides in the worldwide radioactive waste technical community. This knowledge should provide a firm scientific basis on which the long-term performance and safety of a geological repository can be discussed with confidence so informed decisions can be made. Despite this many countries around the world continue to face difficulties with implementing programmes for the deep geological disposal of radioactive waste. Geology, and effective communication of geological knowledge and uncertainty, are essential parts of the 'tool kit' needed to allow meaningful communication and engagement with the public. These tools can be used to build and maintain public confidence at each step in the process. The search for a geological disposal site is complex, with many stages. At each stage, geological uncertainty will inevitable exist as we will never know everything about the sub-surface unless it is mined out at which point it is of no use as a repository! What level

  16. Glucose oxidation and nonoxidative glucose disposal during prolonged fasts of the northern elephant seal pup (Mirounga angustirostris).

    PubMed

    Houser, Dorian S; Crocker, Daniel E; Tift, Michael S; Champagne, Cory D

    2012-09-01

    Elephant seal weanlings demonstrate rates of endogenous glucose production (EGP) during protracted fasts that are higher than predicted on the basis of mass and time fasting. To determine the nonoxidative and oxidative fate of endogenously synthesized glucose, substrate oxidation, metabolic rate, glycolysis, and EGP were measured in fasting weanlings. Eight weanlings were sampled at 14 days of fasting, and a separate group of nine weanlings was sampled at 49 days of fasting. Metabolic rate was determined via flow-through respirometry, and substrate-specific oxidation was determined from the respiratory quotient and urinary nitrogen measurements. The rate of glucose disposal (Glu((R)(d))) was determined through a primed, constant infusion of [3-(3)H]glucose, and glycolysis was determined from the rate of appearance of (3)H in the body water pool. Glu((R)(d)) was 1.41 ± 0.27 and 0.95 ± 0.21 mmol/min in the early and late fasting groups, respectively. Nearly all EGP went through glycolysis, but the percentage of Glu((R)(d)) oxidized to meet the daily metabolic demand was only 24.1 ± 4.4% and 16.7 ± 5.9% between the early and late fasting groups. Glucose oxidation was consistently less than 10% of the metabolic rate in both groups. This suggests that high rates of EGP do not support substrate provisions for glucose-demanding tissues. It is hypothesized that rates of EGP may be ancillary to the upregulation of the tricarboxylic acid cycle to meet high rates of lipid oxidation while mitigating ketosis. PMID:22814669

  17. Design and operational considerations of United States commercial near-surface low-level radioactive waste disposal facilities

    SciTech Connect

    Birk, S.M.

    1997-10-01

    In accordance with the Low-Level Radioactive Waste Policy Amendments Act of 1985, states are responsible for providing for disposal of commercially generated low-level radioactive waste (LLW) within their borders. LLW in the US is defined as all radioactive waste that is not classified as spent nuclear fuel, high-level radioactive waste, transuranic waste, or by-product material resulting from the extraction of uranium from ore. Commercial waste includes LLW generated by hospitals, universities, industry, pharmaceutical companies, and power utilities. LLW generated by the country`s defense operations is the responsibility of the Federal government and its agency, the Department of Energy. The commercial LLRW disposal sites discussed in this report are located near: Sheffield, Illinois (closed); Maxey Flats, Kentucky (closed); Beatty, Nevada (closed); West Valley, New York (closed); Barnwell, South Carolina (operating); Richland, Washington (operating); Ward Valley, California, (proposed); Sierra Blanca, Texas (proposed); Wake County, North Carolina (proposed); and Boyd County, Nebraska (proposed). While some comparisons between the sites described in this report are appropriate, this must be done with caution. In addition to differences in climate and geology between sites, LLW facilities in the past were not designed and operated to today`s standards. This report summarizes each site`s design and operational considerations for near-surface disposal of low-level radioactive waste. The report includes: a description of waste characteristics; design and operational features; post closure measures and plans; cost and duration of site characterization, construction, and operation; recent related R and D activities for LLW treatment and disposal; and the status of the LLW system in the US.

  18. Sampling and analyses of colloids at the Drigg low level radioactive waste disposal site.

    PubMed

    Warwick, P; Allinson, S; Beckett, K; Eilbeck, A; Fairhurst, A; Russel-Flint, K; Verrall, K

    2002-04-01

    Water samples have been extracted from inside (from standpipes) and from outside (from boreholes) of the trenches at the low level radioactive waste disposal site at Drigg in Cumbria, UK. The samples were taken anaerobically from between 8.5 and 10.0 m below the surface using a submersible pump at low flow rates to ensure that the waters in the standpipes and boreholes were maintained at constant levels. To ensure representative samples, the Eh, pH. conductivity, temperature, iron and dissolved oxygen concentrations of the waters were taken during initial purging and during sampling. The gross tritium, gross non-tritium beta, gross alpha and gamma activities of each sample were determined using suitable sample preparation and counting techniques. Samples were then anaerobically, sequentially filtered through 12 microm, 1 microm, 30 kDa and 500 Da filter membranes. The filtrates were analysed for gross alpha, gross non-tritium beta and gamma activities. SEM and STEM analyses were used to determine the colloid population. An energy dispersive analyser on the SEM was used to determine the major elements present in the colloids. UV-visible spectrophotometry, fluorescence spectrophotometry and high performance size exclusion liquid chromatography were used to analyse the waters before and after treatment with ion exchange materials to determine whether natural organic matter was present in the waters. Results showed that two major types of colloids (iron containing colloids and silicon containing colloids) were present in the waters. There were also a small number of other colloids that contain, as major elements, aluminium, calcium and chromium. Organic colloids were also present. The majority of the radioactivity in the waters was due to tritium. Waters taken from outside the trenches contained low levels of non-tritium beta activities and alpha activities which were lower than the minimum detectable amount. Waters taken from the trenches contained non-tritium beta

  19. Sealed Source Security and Disposition: Progress and Prospects - 13515

    SciTech Connect

    Jennison, Meaghan; Martin, David W.

    2013-07-01

    Due to their high activity and portability, unsecured or abandoned sealed sources could cause significant health or environmental damage. Further, some of these sources could be used either individually or in aggregate in radiological dispersal devices commonly referred to as 'dirty bombs', resulting in significant social disruption and economic impacts in the billions of dollars. Disposal access for disused sealed sources, however, has been a serious challenge. From 2008 to 2012, sealed source disposal was available to only 14 states; additionally, waste acceptance criteria for sealed sources at the low-level waste disposal facilities in operation both prior to and after 2012 exclude some common yet potentially dangerous sealed sources. Recent developments, however, suggest that significant improvement in addressing this challenge is possible, although challenges remain. These developments include 1) the initiation of operations at the Waste Control Specialists (WCS) commercial low-level radioactive waste (LLRW) disposal facility in Andrews County, Texas; 2) the potential for significant revisions of the U.S. Nuclear Regulatory Commission's (NRC) 1995 'Final Branch Technical Position on Concentration Averaging and Encapsulation' (1995 BTP); and 3) the Utah Department of Environmental Quality's (UDEQ) approval of a license variance for sealed source disposal at the EnergySolutions LLRW disposal facility near Clive, Utah. (authors)

  20. Use of engineered soils beneath low-level radioactive waste disposal facilities

    SciTech Connect

    Sandford, T.C.; Humphrey, D.N.; DeMascio, F.A.

    1993-03-01

    Current regulations are oriented toward locating low-level radioactive waste disposal facilities on sites that have a substantial natural soil barrier and are above the groundwater table. In some of the northern states, like Maine, the overburden soils are glacially derived and in most places provide a thin cover over bedrock with a high groundwater table. Thus, the orientation of current regulations can severely limit the availability of suitable sites. A common characteristic of many locations in glaciated regions is the rapid change of soil types that may occur and the heterogeneity within a given soil type. In addition, the bedrock may be fractured, providing avenues for water movement. A reliable characterization of these sites can be difficult, even with a detailed subsurface exploration program. Moreover, fluctuating groundwater and frost as well as the natural deposition processes have introduced macro features such as cracks, fissures, sand and silt seams, and root holes. The significant effect that these macro features have on the permeability and adsorptive capacity of a large mass is often ignored or poorly accounted for in the analyses. This paper will examine an alternate approach, which is to use engineered soils as a substitute for some or all of the natural soil and to treat the fractures in the underlying bedrock. The site selection would no longer be primarily determined by the natural soil and rock and could even be placed in locations with no existing soils. Engineered soils can be used for below- or aboveground facilities.

  1. Probability, conditional probability and complementary cumulative distribution functions in performance assessment for radioactive waste disposal

    SciTech Connect

    Helton, J.C.

    1996-03-01

    A formal description of the structure of several recent performance assessments (PAs) for the Waste Isolation Pilot Plant (WIPP) is given in terms of the following three components: a probability space (S{sub st}, S{sub st}, p{sub st}) for stochastic uncertainty, a probability space (S{sub su}, S{sub su}, p{sub su}) for subjective uncertainty and a function (i.e., a random variable) defined on the product space associated with (S{sub st}, S{sub st}, p{sub st}) and (S{sub su}, S{sub su}, p{sub su}). The explicit recognition of the existence of these three components allows a careful description of the use of probability, conditional probability and complementary cumulative distribution functions within the WIPP PA. This usage is illustrated in the context of the U.S. Environmental Protection Agency`s standard for the geologic disposal of radioactive waste (40 CFR 191, Subpart B). The paradigm described in this presentation can also be used to impose a logically consistent structure on PAs for other complex systems.

  2. Review of potential host rocks for radioactive waste disposal in the southern Piedmont

    SciTech Connect

    Marine, I W; Bledsoe, H W

    1982-01-01

    A federal geologic repository is being considered for the disposal of radioactive waste. The geological literature on the Southern Piedmont was studied to identify rock bodies worthy of field exploration for site selection. The study was geotechnical in nature and no consideration was given to socioeconomic factors. There were 13 geotechnical criteria applied in this study of the Southern Piedmont to arrive at a recommendation for further studies on 29 rock bodies. In general, information from the literature included the geometry and depth of the rock body, the lithology and mineralogy of the body, mineral resources, and seismicity of the area. Some rock properties, such as physical, chemical, and thermal characteristics, can be inferred from the lithology and mineralogy of the rock. The subjects on which information from the literature was generally lacking were hydrology and in situ stress. This study was unable to infer the gross hydrologic characteristics from the abundant data in the literature on lithology and structure because few geologic studies report the hydrologic characteristics.

  3. Characterization of Sealed Radioactive Sources: An Uncertainty Analysis to Improve Detection Methods

    SciTech Connect

    Daniel G. Cummings; James D. Sommers; Mary L. Adamic; Marcos Jimenez; Jeffrey G. Giglio; Kevin P. Carney; Karl Grimm

    2009-12-01

    The characterization of several types of sealed radiation sources has been accomplished. Specifically, cesium and strontium sources have been chemically characterized by inductively coupled plasma mass spectrometry (ICP-MS). One of the important pieces of information coming from the characterization is the “age” since purification. The age refers to the time since purification of the Cs or Sr components. A detailed error analysis of the mass spectrometric work has been undertaken to identify areas of improvement, as well as quantitating the effect the errors have on the “age” determined. This paper reports an uncertainty analysis associated with the measurements and identifying areas of improvement and alternative techniques that may reduce the uncertainties. In particular, work on isotope dilution using ICP-MS for the “age” determination of sealed sources will be presented, along with a detailed error analysis. The results will be compared to the original work done with simple instrument calibration.

  4. Method for making a low density polyethylene waste form for safe disposal of low level radioactive material

    DOEpatents

    Colombo, P.; Kalb, P.D.

    1984-06-05

    In the method of the invention low density polyethylene pellets are mixed in a predetermined ratio with radioactive particulate material, then the mixture is fed through a screw-type extruder that melts the low density polyethylene under a predetermined pressure and temperature to form a homogeneous matrix that is extruded and separated into solid monolithic waste forms. The solid waste forms are adapted to be safely handled, stored for a short time, and safely disposed of in approved depositories.

  5. Comparison of selected DOE and non-DOE requirements, standards, and practices for Low-Level Radioactive Waste Disposal

    SciTech Connect

    Cole, L.; Kudera, D.; Newberry, W.

    1995-12-01

    This document results from the Secretary of Energy`s response to Defense Nuclear Facilities Safety Board Recommendation 94--2. The Secretary stated that the US Department of Energy (DOE) would ``address such issues as...the need for additional requirements, standards, and guidance on low-level radioactive waste management. `` The authors gathered information and compared DOE requirements and standards for the safety aspects Of low-level disposal with similar requirements and standards of non-DOE entities.

  6. Analysis and evaluation of a radioactive waste package retrieved from the Farallon Islands 900-meter disposal site

    SciTech Connect

    Colombo, P.; Kendig, M.W.

    1990-09-01

    The Environmental Protection Agency (EPA) was given a Congressional mandate to develop criteria and regulations governing the ocean disposal of all forms of waste. The EPA taken an active role both nationally and within the international nuclear regulatory community to develop the effective controls necessary to protect the health and safety of man and the marine environment. The EPA Office of Radiation Programs (ORP) first initiated feasibility studies to determine whether current technologies could be applied toward determining the fate of radioactive waste disposed of in the past. After successfully locating actual radioactive waste packages in formerly used disposal sites, in the United States, the Office of Radiation Programs developed an intensive program of site characterization studies to examine biological, chemical and physical characteristics including evaluations of the concentration and distribution of radionuclides within these sites, and has conducted a performance evaluation of past packaging techniques and materials. Brookhaven National Laboratory (BNL) has performed container corrosion and matrix analysis studies on the recovered radioactive waste packages. This report presents the final results of laboratory analyses performed. 17 refs., 40 figs., 7 tabs.

  7. Low-level radioactive waste management: transitioning to off-site disposal at Los Alamos National Laboratory

    SciTech Connect

    Dorries, Alison M

    2010-11-09

    Facing the closure of nearly all on-site management and disposal capability for low-level radioactive waste (LLW), Los Alamos National Laboratory (LANL) is making ready to ship the majority of LLW off-site. In order to ship off-site, waste must meet the Treatment, Storage, and Disposal Facility's (TSDF) Waste Acceptance Criteria (WAC). In preparation, LANL's waste management organization must ensure LANL waste generators characterize and package waste compliantly and waste characterization documentation is complete and accurate. Key challenges that must be addressed to successfully make the shift to off-site disposal of LLW include improving the detail, accuracy, and quality of process knowledge (PK) and acceptable knowledge (AK) documentation, training waste generators and waste management staff on the higher standard of data quality and expectations, improved WAC compliance for off-site facilities, and enhanced quality assurance throughout the process. Certification of LANL generators will allow direct off-site shipping of LLW from their facilities.

  8. Cement-based waste forms for disposal of Savannah River Plant low-level radioactive salt waste

    SciTech Connect

    Langton, C A; Dukes, M D; Simmons, R V

    1983-01-01

    Defense waste processing at the Savannah River Plant will include decontamination and disposal of approximately 100 million liters of soluble salts containing primarily NaNO/sub 3/, NaOH, NaNO/sub 2/, NaAl(OH)/sub 4/, and Na/sub 2/SO/sub 4/. A cement-based waste form, saltstone, has been designed for disposal of Savannah River Plant low-level radioactive salt waste. Bulk properties of this material have been tailored with respect to salt leach rate, permeability, and compressive strength. Microstructure and mineralogy of leached and unleached specimens were characterized by SEM and x-ray diffraction analyses, respectively. It has been concluded that the salt leach rate can be limited so that amounts of salt and radionuclides in the groundwater at the perimeter of the 100-acre disposal site will not exceed EPA drinking water standards. 7 references, 4 figures, 6 tables.

  9. Considerations Related To Human Intrusion In The Context Of Disposal Of Radioactive Waste-The IAEA HIDRA Project

    SciTech Connect

    Seitz, Roger; Kumano, Yumiko; Bailey, Lucy; Markley, Chris; Andersson, Eva; Beuth, Thomas

    2014-01-09

    The principal approaches for management of radioactive waste are commonly termed ‘delay and decay’, ‘concentrate and contain’ and ‘dilute and disperse’. Containing the waste and isolating it from the human environment, by burying it, is considered to increase safety and is generally accepted as the preferred approach for managing radioactive waste. However, this approach results in concentrated sources of radioactive waste contained in one location, which can pose hazards should the facility be disrupted by human action in the future. The International Commission on Radiological Protection (ICRP), International Atomic Energy Agency (IAEA), and Organization for Economic Cooperation and Development/Nuclear Energy Agency (OECD/NEA) agree that some form of inadvertent human intrusion (HI) needs to be considered to address the potential consequences in the case of loss of institutional control and loss of memory of the disposal facility. Requirements are reflected in national regulations governing radioactive waste disposal. However, in practice, these requirements are often different from country to country, which is then reflected in the actual implementation of HI as part of a safety case. The IAEA project on HI in the context of Disposal of RadioActive waste (HIDRA) has been started to identify potential areas for improved consistency in consideration of HI. The expected outcome is to provide recommendations on how to address human actions in the safety case in the future, and how the safety case may be used to demonstrate robustness and optimize siting, design and waste acceptance criteria within the context of a safety case.

  10. Native Plant Uptake Model for Radioactive Waste Disposal Areas at the Nevada Test Site

    SciTech Connect

    BROWN,THERESA J.; WIRTH,SHARON

    1999-09-01

    This report defines and defends the basic framework, methodology, and associated input parameters for modeling plant uptake of radionuclides for use in Performance Assessment (PA) activities of Radioactive Waste Management Sites (RWMS) at the Nevada Test Site (NTS). PAs are used to help determine whether waste disposal configurations meet applicable regulatory standards for the protection of human health, the environment, or both. Plants adapted to the arid climate of the NTS are able to rapidly capture infiltrating moisture. In addition to capturing soil moisture, plant roots absorb nutrients, minerals, and heavy metals, transporting them within the plant to the above-ground biomass. In this fashion, plant uptake affects the movement of radionuclides. The plant uptake model presented reflects rooting characteristics important to plant uptake, biomass turnover rates, and the ability of plants to uptake radionuclides from the soil. Parameters are provided for modeling plant uptake and estimating surface contaminant flux due to plant uptake under both current and potential future climate conditions with increased effective soil moisture. The term ''effective moisture'' is used throughout this report to indicate the soil moisture that is available to plants and is intended to be inclusive of all the variables that control soil moisture at a site (e.g., precipitation, temperature, soil texture, and soil chemistry). Effective moisture is a concept used to simplify a number of complex, interrelated soil processes for which there are too little data to model actual plant available moisture. The PA simulates both the flux of radionuclides across the land surface and the potential dose to humans from that flux. Surface flux is modeled here as the amount of soil contamination that is transferred from the soil by roots and incorporated into aboveground biomass. Movement of contaminants to the surface is the only transport mechanism evaluated with the model presented here

  11. Sealed source peer review plan

    SciTech Connect

    Feldman, Alexander; Leonard, Lee; Burns, Ron

    2009-01-01

    Sealed sources are known quantities of radioactive materials that have been encapsulated in quantities that produce known radiation fields. Sealed sources have multiple uses ranging from instrument calibration sources to sources that produce radiation fields for experimental applications. The Off-Site Source Recovery (OSR) Project at Los Alamos National Laboratory (LANL), created in 1999, under the direction of the Waste Management Division of the U.S. Department of Energy (DOE) Albuquerque has been assigned the responsibility to recover and manage excess and unwanted radioactive sealed sources from the public and private sector. LANL intends to ship drums containing qualified sealed sources to the Waste Isolation Pilot Plant (WIPP) for disposal. Prior to shipping, these drums must be characterized with respect to radiological content and other parameters. The U. S. Environmental Protection Agency (EPA) requires that ten radionulcides be quantified and reported for every container of waste to be disposed in the WIPP. The methods traditionally approved by the EPA include non-destructive assay (NDA) in accordance with Appendix A of the Contact-Handled Transuranic Waste Acceptance Criteria for the Waste Isolation Pilot Plant (DOE, 2002) (CH WAC). However, because of the nature and pedigree of historical records for sealed sources and the technical infeasibility of performing NDA on these sources, LANL proposes to characterize the content of these waste drums using qualified existing radiological data in lieu of direct measurement. This plan describes the process and documentation requirements for the use of the peer review process to qualify existing data for sealed radiological sources in lieu of perfonning radioassay. The peer review process will be performed in accordance with criteria provided in 40 CFR {section} 194.22 which specifies the use of the NUREG 1297 guidelines. The plan defines the management approach, resources, schedule, and technical requirements

  12. Developing a low-level radioactive waste disposal facility in Connecticut: Update on progress and new directions

    SciTech Connect

    Gingerich, R.E.

    1993-03-01

    Connecticut is a member of the Northeast Interstate Low-Level Radioactive Waste Management Compact (Northeast LLRW Compact). The other member of the Northeast LLRW Compact is New Jersey. The Northeast Interstate Low-Level Radioactive Waste Commission (Northeast Compact Commission), the Northeast LLRW Compact`s governing body, has designated both Connecticut and New Jersey as host states for disposal facilities. The Northeast Compact Commission has recommended that, for purposes of planning for each state`s facility, the siting agency for the state should use projected volumes and characteristics of the LLW generated in its own state. In 1987 Connecticut enacted legislation that assigns major responsibilities for developing a LLW disposal facility in Connecticut to the Connecticut Hazardous Waste Management Service (CHWMS). The CHWMS is required to: prepare and revise, as necessary, a LLW Management Plan for the state; select a site for a LLW disposal facility; select a disposal technology to be used at the site; select a firm to obtain the necessary approvals for the facility and to develop and operate it; and serve as the custodial agency for the facility. This paper discusses progress in developing a facility.

  13. Total occupational exposure during characterisation, conditioning and securing of radioactive sealed sources: a new dosimetric concept using active electronic dosimeters.

    PubMed

    Prlić, Ivica; Mihić, Marija Surić; Marović, Gordana; Mestrović, Tomislav

    2009-03-01

    Radiation dosimetry in protection against ionising radiation involves research of all possible pathways through which natural or man-made radioactive materials can contaminate a habitat and actually harm its biota. It also takes into account natural and artificial (man-made) electromagnetic ionizing radiation (gamma and x radiation). This article presents a dosimetric study assessing exposure to man-made ionising radiation of local environment and total occupational exposure of two professional workers involved in characterisation, conditioning, and securing of unused radioactive sealed sources. The purpose of the study was to validate a new active electronic dosimeter (AED) of type ALARA OD and to develop a new monitoring method by tracing the external occupational exposure over real time. This method is used to continuously measure and record external radiation doses and, which is a novelty, establish dose rates receiving pattern as a function of real time. Occupational whole body dosimetric results obtained with AED were compared with results obtained with passive dosimetry (film badge and thermoluminiscence). Air, dust, and silicon sand samples were analysed by gamma-spectrometry to estimate internal exposure of the two workers to 222Rn due to inhalation or ingestion of dust and sand in indoor air. In order to establish total occupational exposure, control radon measurement was performed in the immediate environment and the external Hazard index (Hex) was calculated. PMID:19329376

  14. Survey of degradation modes of candidate materials for high-level radioactive-waste disposal containers

    SciTech Connect

    Farmer, J.C.; Van Konynenburg, R.A.; McCright, R.D. ); Gdowski, G.E. )

    1988-06-01

    Three copper-based alloys, CDA 102 (oxygen-free, high-purity copper), CDA 613 (aluminum bronze), and CDA 715 (Cu-30Ni), are candidates for the fabrication of high-level radioactive-waste disposal containers. Waste will include spent fuel assemblies from reactors as well as borosilicate glass, and will be sent to the prospective repository site at Yucca Mountain in Nye County, Nevada. The decay of radionuclides will result in the generation of substantial heat and in fluxes of gamma radiation outside the containers. In this environment, container materials might degrade by atmospheric oxidation, general aqueous phase corrosion, localized corrosion (LC), and stress corrosion cracking (SCC). This volume is a critical survey of available data on pitting and crevice corrosion of the copper-based candidates. Pitting and crevice corrosion are two of the most common forms of LC of these materials. Data on the SCC of these alloys is surveyed in Volume 4. Pitting usually occurs in water that contains low concentrations of bicarbonate and chloride anions, such as water from Well J-13 at the Nevada Test Site. Consequently, this mode of degradation might occur in the repository environment. Though few quantitative data on LC were found, a tentative ranking based on pitting corrosion, local dealloying, crevice corrosion, and biofouling is presented. CDA 102 performs well in the categories of pitting corrosion, local dealloying, and biofouling, but susceptibility to crevice corrosion diminishes its attractiveness as a candidate. The cupronickel alloy, CDA 715, probably has the best overall resistance to such localized forms of attack. 123 refs., 11 figs., 3 tabs.

  15. Site selection and licensing issues: Southwest Compact low-level radioactive waste disposal site

    SciTech Connect

    Grant, J.L.

    1989-11-01

    The low-level radioactive waste disposal site in California is being selected through a three-phase program. Phase 1 is a systematic statewide, regional, and local screening study. This program was conducted during 1986 and 1987, and culminated in the selection of three candidate sites fur further study. The candidate sites are identified as the Panamint, Silurian, and Ward Valley sites. Phase 2 comprises site characterization and environmental and socio-economic impact study activities at the three candidate sites. Based upon the site characterization studies, the candidate sites are ranked according to the desirability and conformance with regulatory requirements. Phase 3 comprises preparation of a license application for the selected candidate site. The license application will include a detailed characterization of the site, detailed design and operations plans for the proposed facility, and assessments of potential impacts of the site upon the environment and the local communities. Five types of siting criteria were developed to govern the site selection process. These types are: technical suitability exclusionary criteria, high-avoidance criteria beyond technical suitability requirements, discretionary criteria, public acceptance, and schedule requirements of the LLWR Policy Act Amendments. This paper discusses the application of the hydrological and geotechnical criteria during the siting and licensing studies in California. These criteria address site location and performance, and the degree to which present and future site behavior can be predicted. Primary regulatory requirements governing the suitability of a site are that the site must be hydrologically and geologically simple enough for the confident prediction of future behavior, and that the site must be stable enough that frequent or intensive maintenance of the closed site will not be required. This paper addresses the methods to measure site suitability at each stage of the process, methods to

  16. Integrated Numerical Simulation of Thermo-Hydro-Chemical Phenomena Associated with Geologic Disposal of High-Level Radioactive Waste

    NASA Astrophysics Data System (ADS)

    Park, Sang-Uk; Kim, Jun-Mo; Kihm, Jung-Hwi

    2014-05-01

    A series of numerical simulations was performed using a multiphase thermo-hydro-chemical numerical model to predict integratedly and evaluate quantitatively thermo-hydro-chemical phenomena due to heat generation associated with geologic disposal of high-level radioactive waste. The average mineralogical composition of the fifteen unweathered igneous rock bodies, which were classified as granite, in Republic of Korea was adopted as an initial (primary) mineralogical composition of the host rock of the repository of high-level radioactive waste in the numerical simulations. The numerical simulation results show that temperature rises and thus convective groundwater flow occurs near the repository due to heat generation associated with geologic disposal of high-level radioactive waste. Under these circumstances, a series of water-rock interactions take place. As a result, among the primary minerals, quartz, plagioclase (albite), biotite (annite), and muscovite are dissolved. However, orthoclase is initially precipitated and is then dissolved, whereas microcline is initially dissolved and is then precipitated. On the other hand, the secondary minerals such as kaolinite, Na-smectite, chlorite, and hematite are precipitated and are then partly dissolved. In addition, such dissolution and precipitation of the primary and secondary minerals change groundwater chemistry (quality) and induce reactive chemical transport. As a result, in groundwater, Na+, Fe2+, and HCO3- concentrations initially decrease, whereas K+, AlO2-, and aqueous SiO2 concentrations initially increase. On the other hand, H+ concentration initially increases and thus pH initially decreases due to dissociation of groundwater in order to provide OH-, which is essential in precipitation of Na-smectite and chlorite. Thus, the above-mentioned numerical simulation results suggest that thermo-hydro-chemical numerical simulation can provide a better understanding of heat transport, groundwater flow, and reactive

  17. Radioactivity determination of sealed pure beta-sources by surface dose measurements and Monte Carlo simulations

    NASA Astrophysics Data System (ADS)

    Choi, Chang Heon; Jung, Seongmoon; Choi, Kanghyuk; Son, Kwang-Jae; Lee, Jun Sig; Ye, Sung-Joon

    2016-04-01

    This study aims to determine the activity of a sealed pure beta-source by measuring the surface dose rate using an extrapolation chamber. A conversion factor (cGy s-1 Bq-1), which was defined as the ratio of surface dose rate to activity, can be calculated by Monte Carlo simulations of the extrapolation chamber measurement. To validate this hypothesis the certified activities of two standard pure beta-sources of Sr/Y-90 and Si/P-32 were compared with those determined by this method. In addition, a sealed test source of Sr/Y-90 was manufactured by the HANARO reactor group of KAERI (Korea Atomic Energy Research Institute) and used to further validate this method. The measured surface dose rates of the Sr/Y-90 and Si/P-32 standard sources were 4.615×10-5 cGy s-1 and 2.259×10-5 cGy s-1, respectively. The calculated conversion factors of the two sources were 1.213×10-8 cGy s-1 Bq-1 and 1.071×10-8 cGy s-1 Bq-1, respectively. Therefore, the activity of the standard Sr/Y-90 source was determined to be 3.995 kBq, which was 2.0% less than the certified value (4.077 kBq). For Si/P-32 the determined activity was 2.102 kBq, which was 6.6% larger than the certified activity (1.971 kBq). The activity of the Sr/Y-90 test source was determined to be 4.166 kBq, while the apparent activity reported by KAERI was 5.803 kBq. This large difference might be due to evaporation and diffusion of the source liquid during preparation and uncertainty in the amount of weighed aliquot of source liquid. The overall uncertainty involved in this method was determined to be 7.3%. We demonstrated that the activity of a sealed pure beta-source could be conveniently determined by complementary combination of measuring the surface dose rate and Monte Carlo simulations.

  18. Underground Architecture and Layout for the Belgian High-Level and Long-Lived Intermediate-Level Radioactive Waste Disposal Facility- 12116

    SciTech Connect

    Van Cotthem, Alain; Van Humbeeck, Hughes

    2012-07-01

    The underground architecture and layout of the proposed Belgian high-level (HLW) and long-lived, intermediate-level radioactive wastes (ILW-LL) disposal system (repository) is mainly based on lessons learned during the development and 30-year-long operation of an underground research laboratory (URL) ('HADES') located adjacent to the city of Mol at a depth of 225 m in a 100-m-thick, Tertiary clay formation; the Boom clay. The following main operational and safety challenges are addressed in the proposed architecture and layout: 1. Following excavation, the underground openings needed to be promptly supported to minimize the extent of the excavation damaged zone (EDZ). 2. The size and unsupported stand-up time at tunnel crossings/intersections also needed to be minimized to minimize the extent of the related EDZ. 3. Steel components had to be minimized to limit the related long-term (post-closure) corrosion and hydrogen production. 4. The shafts and all equipment had to go down through a 180-m-thick aquifer and handle up to 65-Ton payloads. 5. The shaft seals had to be placed in the underlying clay layer. The currently proposed layout minimizes the excavated volume based on strict long-term-safety criteria and optimizes operational safety. Operational safety is further enhanced by a remote-controlled waste-package-handling system transporting the waste packages from their respective surface location down to their respective disposal location with no intermediate operation. The related on-site preparation and thenceforth use of cement-based, waste package- transportation containers are integral operational-safety components. In addition to strengthening the waste packages and providing radiation protection, these containers also provide long-term corrosion protection of the internal 'primary' steel packages. (authors)

  19. Study of extraterrestrial disposal of radioactive wastes. Part 3: Preliminary feasibility screening study of space disposal of the actinide radioactive wastes with 1 percent and 0.1 percent fission product contamination

    NASA Technical Reports Server (NTRS)

    Hyland, R. E.; Wohl, M. L.; Finnegan, P. M.

    1973-01-01

    A preliminary study was conducted of the feasibility of space disposal of the actinide class of radioactive waste material. This waste was assumed to contain 1 and 0.1 percent residual fission products, since it may not be feasible to completely separate the actinides. The actinides are a small fraction of the total waste but they remain radioactive much longer than the other wastes and must be isolated from human encounter for tens of thousands of years. Results indicate that space disposal is promising but more study is required, particularly in the area of safety. The minimum cost of space transportation would increase the consumer electric utility bill by the order of 1 percent for earth escape and 3 percent for solar escape. The waste package in this phase of the study was designed for normal operating conditions only; the design of next phase of the study will include provisions for accident safety. The number of shuttle launches per year required to dispose of all U.S. generated actinide waste with 0.1 percent residual fission products varies between 3 and 15 in 1985 and between 25 and 110 by 2000. The lower values assume earth escape (solar orbit) and the higher values are for escape from the solar system.

  20. Stakeholder Engagement on the Environmental Impact Statement for the Disposal of Greater-Than-Class C Low-Level Radioactive Waste -12565

    SciTech Connect

    Gelles, Christine; Joyce, James; Edelman, Arnold

    2012-07-01

    The Department of Energy's (DOE) Office of Disposal Operations is responsible for developing a permanent disposal capability for a small volume, but highly radioactive, class of commercial low-level radioactive waste, known as Greater-Than-Class C (GTCC) low-level radioactive waste. DOE has issued a draft environmental impact statement (EIS) and will be completing a final EIS under the National Environmental Policy Act (NEPA) that evaluates a range of disposal alternatives. Like other classes of radioactive waste, proposing and evaluating disposal options for GTCC waste is highly controversial, presents local and national impacts, and generates passionate views from stakeholders. Recent national and international events, such as the cancellation of the Yucca Mountain project and the Fukushima Daiichi nuclear accident, have heighten stakeholder awareness of everything nuclear, including disposal of radioactive waste. With these challenges, the Office of Disposal Operations recognizes that informed decision-making that will result from stakeholder engagement and participation is critical to the success of the GTCC EIS project. This paper discusses the approach used by the Office of Disposal Operations to engage stakeholders on the GTCC EIS project, provides advice based on our experiences, and proffers some ideas for future engagements in today's open, always connected cyber environment. (authors)

  1. Studies concerning the durability of concrete vaults for intermediate level radioactive waste disposal: Electrochemical monitoring and corrosion aspects

    NASA Astrophysics Data System (ADS)

    Duffó, G. S.; Farina, S. B.; Arva, E. A.; Giordano, C. M.; Lafont, C. J.

    2006-11-01

    The Argentine Atomic Energy Commission (CNEA) is responsible of the development of a management nuclear waste disposal programme. This programme contemplates the design and construction of a facility for the final disposal of intermediate-level radioactive waste. The proposed concept is the near-surface monolithic repository similar to those in operation in El Cabril, Spain. The design of this type of repository is based on the use of multiple, independent and redundant barriers. Since the vault and cover are major components of the engineered barriers, the durability of these concrete structures is an important aspect for the facilities integrity. This work presents a laboratory and field investigation performed for the last 6 years on reinforced concrete specimens, in order to predict the service life of the intermediate level radioactive waste disposal vaults from data obtained from electrochemical techniques. On the other hand, the development of sensors that allow on-line measurements of rebar corrosion potential and corrosion current density; incoming oxygen flow that reaches the metal surface; concrete electrical resistivity and chloride concentration is shown. Those sensors, properly embedded in a new full scale vault (nowadays in construction), will allow the monitoring of the corrosion process of the steel rebars embedded in thestructure.

  2. Collapsable seal member

    SciTech Connect

    Sherrell, Dennis L.

    1990-01-01

    A hollow, collapsable seal member normally disposed in a natural expanded state offering fail-safe pressure sealing against a seating surface and adapted to be evacuated by a vacuum force for collapsing the seal member to disengage the same from said seating surface.

  3. Collapsable seal member

    SciTech Connect

    Sherrell, D.L.

    1983-12-08

    A hollow, collapsable seal member normally disposed in a natural expanded state offering fail-safe pressure sealing against a seating surface and adapted to be evacuated by a vacuum force for collapsing the seal member to disengage the same from said seating surface.

  4. Linking RESRAD-OFFSITE and HYDROGEOCHEM Model for Performance Assessment of Low-Level Radioactive Waste Disposal Facility - 13429

    SciTech Connect

    Lin, Wen-Sheng; Yu, Charley; Cheng, Jing-Jy; Kamboj, Sunita; Gnanapragasam, Emmanuel; Liu, Chen-Wuing; Li, Ming-Hsu

    2013-07-01

    Performance assessments are crucial steps for the long-term radiological safety requirements of low-level waste (LLW) disposal facility. How much concentration of radionuclides released from the near-field to biosphere and what radiation exposure levels of an individual can influence on the satisfactory performance of the LLW disposal facility and safety disposal environment. Performance assessment methodology for the radioactive waste disposal consists of the reactive transport modeling of safety-concerned radionuclides released from the near-field to the far-field, and the potential exposure pathways and the movements of radionuclides through the geosphere, biosphere and man of which the accompanying dose. Therefore, the integration of hydrogeochemical transport model and dose assessment code, HYDROGEOCHEM code and RESRAD family of codes is imperative. The RESRAD family of codes such as RESRAD-OFFSITE computer code can evaluate the radiological dose and excess cancer risk to an individual who is exposed while located within or outside the area of initial (primary) contamination. The HYDROGEOCHEM is a 3-D numerical model of fluid flow, thermal, hydrologic transport, and biogeochemical kinetic and equilibrium reactions in saturated and unsaturated media. The HYDROGEOCHEM model can also simulate the crucial geochemical mechanism, such as the effect of redox processes on the adsorption/desorption, hydrogeochemical influences on concrete degradation, adsorption/desorption of radionuclides (i.e., surface complexation model) between solid and liquid phase in geochemically dynamic environments. To investigate the safety assessment of LLW disposal facility, linking RESRAD-OFFSITE and HYDROGEOCHEM model can provide detailed tools of confidence in the protectiveness of the human health and environmental impact for safety assessment of LLW disposal facility. (authors)

  5. Saltstone: cement-based waste form for disposal of Savannah River Plant low-level radioactive salt waste

    SciTech Connect

    Langton, C.A.

    1984-01-01

    Defense waste processing at the Savannah River Plant will include decontamination and disposal of approximately 400 million liters of waste containing NaNO/sub 3/, NaOH, Na/sub 2/SO/sub 4/, and NaNO/sub 2/. After decontamination, the salt solution is classified as low-level waste. A cement-based waste form, saltstone, has been designed for disposal of Savannah River Plant low-level radioactive salt waste. Bulk properties of this material have been tailored with respect to salt leach rate, permeability, and compressive strength. Microstructure and mineralogy of leached and unleached specimens were characterized by SEM and x-ray diffraction analyses. The disposal system for the DWPF salt waste includes reconstitution of the crystallized salt as a solution containing 32 wt % solids. This solution will be decontaminated to remove /sup 137/Cs and /sup 90/Sr and then stabilized in a cement-based waste form. Laboratory and field tests indicate that this stabilization process greatly reduces the mobility of all of the waste constitutents in the surface and near-surface environment. Engineered trenches for subsurface burial of the saltstone have been designed to ensure compatibility between the waste form and the environment. The total disposal sytem, saltstone-trench-surrounding soil, has been designed to contain radionuclides, Cr, and Hg by both physical encapsulation and chemical fixation mechanisms. Physical encapsulation of the salts is the mechanism employed for controlling N and OH releases. In this way, final disposal of the SRP low-level waste can be achieved and the quality of the groundwater at the perimeter of the disposal site meets EPA drinking water standards.

  6. Development of Risk Insights for Regulatory Review of a Near-Surface Disposal Facility for Radioactive Waste

    SciTech Connect

    Esh, D.W.; Ridge, A.C.; Thaggard, M.

    2006-07-01

    Section 3116 of the Ronald W. Reagan National Defense Authorization Act for Fiscal Year 2005 (NDAA) requires the Department of Energy (DOE) to consult with the Nuclear Regulatory Commission (NRC) about non-High Level Waste (HLW) determinations. In its consultative role, NRC performs technical reviews of DOE's waste determinations but does not have regulatory authority over DOE's waste disposal activities. The safety of disposal is evaluated by comparing predicted disposal facility performance to the performance objectives specified in NRC regulations for the disposal of low-level waste (10 CFR Part 61 Subpart C). The performance objectives contain criteria for protection of the public, protection of inadvertent intruders, protection of workers, and stability of the disposal site after closure. The potential radiological dose to receptors typically is evaluated with a performance assessment (PA) model that simulates the release of radionuclides from the disposal site, transport of radionuclides through the environment, and exposure of potential receptors to residual contamination for thousands of years. This paper describes NRC's development and use of independent performance assessment modeling to facilitate review of DOE's non-HLW determination for the Saltstone Disposal Facility (SDF) at the Savannah River Site. NRC's review of the safety of near-surface disposal of radioactive waste at the SDF was facilitated and focused by risk insights developed with an independent PA model. The main components of NRC's performance assessment model are presented. The development of risk insights that allow the staff to focus review efforts on those areas that are most important to satisfying the performance objectives is discussed. Uncertainty analysis was performed of the full stochastic model using genetic variable selection algorithms. The results of the uncertainty analysis were then used to guide the development of simulations of other scenarios to understand the key risk

  7. Environmental monitoring report for commercial low-level radioactive waste disposal sites (1960`s through 1990`s)

    SciTech Connect

    1996-11-01

    During the time period covered in this report (1960`s through early 1990`s), six commercial low-level radioactive waste (LLRW) disposal facilities have been operated in the US. This report provides environmental monitoring data collected at each site. The report summarizes: (1) each site`s general design, (2) each site`s inventory, (3) the environmental monitoring program for each site and the data obtained as the program has evolved, and (4) what the program has indicated about releases to off-site areas, if any, including a statement of the actual health and safety significance of any release. A summary with conclusions is provided at the end of each site`s chapter. The six commercial LLRW disposal sites discussed are located near: Sheffield, Illinois; Maxey Flats, Kentucky; Beatty, Nevada; West Valley, New York; Barnwell, South Carolina; Richland, Washington.

  8. Hydrogeology of a fractured shale (Opalinus Clay): Implications for deep geological disposal of radioactive wastes

    NASA Astrophysics Data System (ADS)

    Gautschi, Andreas

    2001-01-01

    As part of the Swiss programme for high-level radioactive-waste disposal, a Jurassic shale (Opalinus Clay) is being investigated as a potential host rock. Observations in clay pits and the results of a German research programme focusing on hazardous waste disposal have demonstrated that, at depths of 10-30 m, the permeability of the Opalinus Clay decreases by several orders of magnitude. Hydraulic tests in deeper boreholes (test intervals below 300 m) yielded hydraulic conductivities <10-12 m/s, even though joints and faults were included in some of the test intervals. These measurements are consistent with hydrogeological data from Opalinus Clay sections in ten tunnels in the Folded Jura of northern Switzerland. Despite extensive faulting, only a few indications of minor water inflow were encountered in more than 6,600 m of tunnel. All inflows were in tunnel sections where the overburden is less than 200 m. The hydraulic data are consistent with clay pore-water hydrochemical and isotopic data. The extensive hydrogeological data base - part of which derives from particularly unfavourable geological environments - provides arguments that advective transport through faults and joints is not a critical issue for the suitability of Opalinus Clay as a host rock for deep geological waste disposal. Résumé. Dans le cadre du programme suisse de stockage de déchets hautement radioactifs, une formation argileuse du Jurassique, l'argile à Opalinus, a été étudiée en tant que roche hôte potentielle. Des observations dans des cavités dans l'argile et les résultats du programme de recherche allemand consacré au stockage de déchets à risques ont démontré que, à des profondeur de 10 à 30 m, la perméabilité des argiles à Opalinus décroît de plusieurs ordres de grandeur. Des essais hydrauliques dans des forages plus profonds (intervalles de test á une profondeur de plus de 300 m) ont donné des conductivités hydrauliques inférieures à 10-12 m/s, m

  9. Hydrogeology of a fractured shale (Opalinus Clay): Implications for deep geological disposal of radioactive wastes

    NASA Astrophysics Data System (ADS)

    Gautschi, Andreas

    2001-01-01

    As part of the Swiss programme for high-level radioactive-waste disposal, a Jurassic shale (Opalinus Clay) is being investigated as a potential host rock. Observations in clay pits and the results of a German research programme focusing on hazardous waste disposal have demonstrated that, at depths of 10-30 m, the permeability of the Opalinus Clay decreases by several orders of magnitude. Hydraulic tests in deeper boreholes (test intervals below 300 m) yielded hydraulic conductivities <10-12 m/s, even though joints and faults were included in some of the test intervals. These measurements are consistent with hydrogeological data from Opalinus Clay sections in ten tunnels in the Folded Jura of northern Switzerland. Despite extensive faulting, only a few indications of minor water inflow were encountered in more than 6,600 m of tunnel. All inflows were in tunnel sections where the overburden is less than 200 m. The hydraulic data are consistent with clay pore-water hydrochemical and isotopic data. The extensive hydrogeological data base - part of which derives from particularly unfavourable geological environments - provides arguments that advective transport through faults and joints is not a critical issue for the suitability of Opalinus Clay as a host rock for deep geological waste disposal. Résumé. Dans le cadre du programme suisse de stockage de déchets hautement radioactifs, une formation argileuse du Jurassique, l'argile à Opalinus, a été étudiée en tant que roche hôte potentielle. Des observations dans des cavités dans l'argile et les résultats du programme de recherche allemand consacré au stockage de déchets à risques ont démontré que, à des profondeur de 10 à 30 m, la perméabilité des argiles à Opalinus décroît de plusieurs ordres de grandeur. Des essais hydrauliques dans des forages plus profonds (intervalles de test á une profondeur de plus de 300 m) ont donné des conductivités hydrauliques inférieures à 10-12 m/s, m

  10. Application of Polymers for the Long-Term Storage and Disposal of Low- and Intermediate-Level Radioactive Waste

    SciTech Connect

    Bonin, Hugues W.; Walker, Michael W.; Bui, Van Tam

    2004-01-15

    Research carried out at the Royal Military College of Canada on the effects of mixed fields of radiation on high polymer adhesives and composite materials has shown that some polymers are quite resistant to radiation and could well serve in the fabrication of radioactive-waste disposal containers. A research program was launched to investigate the possibilities of using advanced polymers and polymer-based composites for high-level radioactive waste management on one hand and for intermediate- and low-level radioactive waste disposal on the other hand. Research was thus conducted in parallel on both fronts, and the findings for the later phase are presented. Thermoplastic polymers were studied for this application because they are superior materials, having the advantage over metals of not corroding and of displaying high resistance to chemical aggression. The experimental methods used in this research focused on determining the effects of radiation on the properties of the materials considered: polypropylene, nylon 66, polycarbonate, and polyurethane, with and without glass fiber reinforcement. The method involved submitting injection-molded tensile test bars to the mixed radiation field generated by the SLOWPOKE-2 nuclear reactor at the Royal Military College of Canada to accumulate doses ranging from 0.5 to 3.0 MGy. The physical, mechanical, and chemical effects of the various radiation doses on the materials were measured from density, tensile, differential scanning calorimetry, and scanning electron microscopy tests.For each polymer, the test results evidenced predominant cross-linking of the polymeric chains severed by radiation. This was evident from observed changes in the mechanical and chemical properties of the polymers, typical of cross-linking. The mechanical changes observed included an overall increase in density, an increase in Young's modulus, a decrease in strain at break, and only minor changes in strength. The chemical changes included

  11. Guidance on the application of quality assurance for characterizing a low-level radioactive waste disposal site

    SciTech Connect

    Pittiglio, C.L. Jr.; Starmer, R.J.; Hedges, D.

    1990-10-01

    This document provides the Nuclear Regulatory Commission's staff guidance to an applicant on meeting the quality control (QC) requirements of Title 10 of the Code of Federal Regulations, Part 61, Section 61.12 (10 CFR 61.12), for a low-level waste disposal facility. The QC requirements combined with the requirements for managerial controls and audits are the basis for developing a quality assurance (QA) program and for the guidance provided herein. QA guidance is specified for site characterization activities necessary to meet the performance objectives of 10 CFR Part 61 and to limit exposure to or the release of radioactivity. 1 tab.

  12. Radioactive waste isolation in salt: peer review of the D'Appolonia report on Schematic Designs for Penetration Seals for a Repository in the Permian Basin, Texas

    SciTech Connect

    Hambley, D.F.; Stormont, J.C.; Russell, J.E.; Edgar, D.E.; Fenster, D.F.; Harrison, W.; Tisue, M.W.

    1984-09-01

    Argonne made the following recommedations for improving the reviewed reports. The authors of the report should: state the major assumptions of the study in Sec. 1.1 rather than later in the report; consider using salt for the shaft seals in salt horizons; reconsider whether keys are needed for the bulkheads; provide for interface grouting because use of expansive cement will not guarantee that interfaces will be impermeable; discuss the sealing schedule and, where appropriate, consider what needs to be done to ensure that emplaced radioactive waste could be retrieved if necessary; describe in more detail the sealing of the Dockum and Ogallala aquifers; consider an as low as reasonably achievable approach to performance requirements for the initial design phase; address the concerns in the 1983 US Nuclear Regulatory Commission document entitled Draft Technical Position: Borehole and Shaft Sealing of High-Level Nuclear Waste Repositories; cite the requirements for release of radioactivity by referring to specific clauses in the regulations of the US Environmental Protection Agency; and provide further explanation in the outline of future activities about materials development and verification testing. More emphasis on development of accelerated testing programs is also required.

  13. Sealed source and device design safety testing. Volume 5: Technical report on the findings of Task 4, Investigation of failed radioactive stainless steel troxler gauges

    SciTech Connect

    Benac, D.J.; Schick, W.R.

    1995-10-01

    This report covers the Task 4 activities for the Sealed Source and Device Safety testing program. SwRI was contracted to investigate failed radioactive stainless steel troxler gauges. SwRI`s task was to determine the cause of failure of the rods and the extent of the problem. SwRI concluded that the broken rod failed in a brittle manner due to a hard zone in the heat affected zone.

  14. FINAL DISPOSAL OF RADIOACTIVE WASTE IN GERMANY: PLAN APPROVAL PROCESS OF KONRAD MINE AND ACCEPTANCE REQUIREMENTS

    SciTech Connect

    Bandt, Gabriele; Posnatzki, Britta; Beckers, Klaus-Arno

    2003-02-27

    Currently no final repository for any type of radioactive waste is operated in Germany. Preliminary Final Storage Acceptance Requirements for radioactive waste packages were published in 1995. Up to now these are the basis for treatment of radioactive waste in Germany. After licensing of the final repository these preliminary waste acceptance requirements are completed with licensing conditions. Some of these conditions affect the preliminary waste acceptance requirements, e. g. behavior of chemo-toxic substances in case of accidents in the final repository or the allowed maximum concentration of fissile material. The presented examples of radioactive waste conditioning campaigns demonstrate that no difficulties are expected in management, characterization and quality assurance of radioactive wastes due to the licensing conditions.

  15. Model for inactivation and disposal of infectious human immunodeficiency virus and radioactive waste in a BL3 facility.

    PubMed Central

    Stinson, M C; Galanek, M S; Ducatman, A M; Masse, F X; Kuritzkes, D R

    1990-01-01

    A method is described for autoclaving low levels of solid infectious, radioactive waste. The method permits steam penetration to inactivate biologic waste, while any volatile radioactive compounds generated during the autoclave process are absorbed. Inactivation of radiolabeled infectious waste has been problematic because the usual sterilization techniques result in unacceptable radiation handling practices. If autoclaved under the usual conditions, there exists a high probability of volatilization or release of radioisotopes from the waste. This results in the radioactive contamination of the autoclave and the laboratory area where steam is released from the autoclave. Our results provide a practical method to inactivate and dispose of infectious radioactive waste. For our research, Bacillus pumilus spore strips and vaccinia virus were used as more heat-resistant surrogates of the human immunodeficiency virus (HIV). These surrogates were used because HIV is difficult to grow under most conditions and is less heat tolerant than the surrogates. In addition, B. pumilus has defined cell death values, whereas such values have not been established for HIV. Both B. pumilus and vaccinia virus are less hazardous to work with. The autoclave method is time efficient and can be performed by laboratory personnel with minimal handling of the waste. Furthermore, waste site handlers are able to visually inspect the solid waste containers and ascertain that inactivation procedures have been implemented. PMID:2310182

  16. A brief analysis and description of transuranic wastes in the Subsurface Disposal Area of the radioactive waste management complex at INEL

    SciTech Connect

    Arrenholz, D.A.; Knight, J.L.

    1991-08-01

    This document presents a brief summary of the wastes and waste types disposed of in the transuranic contaminated portions of the Subsurface Disposal Area of the radioactive waste management complex at Idaho National Engineering Laboratory from 1954 through 1970. Wastes included in this summary are organics, inorganics, metals, radionuclides, and atypical wastes. In addition to summarizing amounts of wastes disposed and describing the wastes, the document also provides information on disposal pit and trench dimensions and contaminated soil volumes. The report also points out discrepancies that exist in available documentation regarding waste and soil volumes and make recommendations for future efforts at waste characterization. 19 refs., 3 figs., 17 tabs.

  17. Evapotranspiration and microclimate at a low-level radioactive-waste disposal site in northwestern Illinois

    USGS Publications Warehouse

    Healy, R.W.; DeVries, M.P.; Sturrock, Alex M., Jr.

    1989-01-01

    From July 1982 through June 1984, a study was made of the evapotranspiration and microclimate at a low-level radioactive-waste disposal site near Sheffield, Bureau County, Illinois. Vegetation at the site consists of mixed pasture grasses, primarily awnless brome (Bromus inermis) and red clover (Trifoleum pratense). Three methods were used to estimate evapotranspiration: (1) an energy budget with the Bowen ratio, (2) an aerodynamic profile, and (3) a soil-based water budget. For the aerodynamic-profile method, sensible-heat flux was estimated by a profile equation and evapotranspiration was then calculated as the residual in the energy-balance equation. Estimates by the energy-budget and aerodynamic-profile methods were computed from hourly data and then summed by days and months. Yearly estimates (for March through November) by these methods were in close agreement: 648 and 626 millimeters, respectively. Daily estimates reach a maximum of about 6 millimeters. The water-budget method produced only monthly estimates based on weekly or biweekly soil-moisture content measurements. The yearly evapotranspiration estimated by this method (which actually included only the months of April through October) was 655 millimeters. The March-through-November average for the three methods of 657 millimeters was equivalent to 70 percent of total precipitation. Continuous measurements were made of incoming and reflected shortwave radiation, incoming and emitted longwave radiation, net radiation, soil-heat flux, soil temperature, horizontal windspeed, and wet- and dry-bulb air temperature. Windspeed and air temperature were measured at heights of 0.5 and 2.0 meters (and also at 1.0 meter after September 1983). Soilmoisture content of the soil zone was measured with a gamma-attenuation gage. Annual precipitation (938 millimeters) and average temperature (10.8 degrees Celsius) at the Sheffield site were virtually identical to long-term averages from nearby National Weather Service

  18. Evapotranspiration and microclimate at a low-level radioactive-waste disposal site in northwestern Illinois

    USGS Publications Warehouse

    Healy, R.W.; DeVries, M.P.; Sturrock, A.M.

    1987-01-01

    From July 1982 through June 1984, a study was made of the microclimate and evapotranspiration at a low-level radioactive-waste disposal site near Sheffield, Bureau County, Illinois. Vegetation at the site consists of mixed pasture grasses, primarily brome (Bromus inermis) and red clover (Trifoleum pratense). Three methods were used to estimate evapotranspiration: (1) an energy-budget with the Bowen ratio, (2) an aerodynamic-profile, and (3) a soil-based water-budget. For the aerodynamic-profile method, sensible-heat flux was estimated by a profile equation and evapotranspiration was then calculated as the residual in the energy-balance equation. Estimates by the energy-budget and aerodynamic-profile methods were computed from hourly data, then summed by days and months. Yearly estimates for March through November, by these methods, were quite close--648 and 626 millimeters, respectively. Daily estimates range up to a maximum of about 6 millimeters. The water-budget method produced only monthly estimates based on weekly or biweekly soil-moisture content measurements. The yearly evapotranspiration estimated by this method (which actually included only the months of April through October) was 655 millimeters. The March-through-November average for the three methods of 657 millimeters was equivalent to 70 percent of precipitation. Continuous measurements were made of incoming and reflected shortwave radiation, incoming and emitted longwave radiation, net radiation, soil-heat flux, soil temperature, horizontal windspeed, and wet- and dry-bulb air temperature. Windspeed and air temperature were measured at heights of 0.5 and 2.0 meters (and also at 1.0 meter after September 1983). Soil-moisture content of the soil zone was measured with a gamma-attenuation gage. Annual precipitation (938 millimeters) and average temperature (10.8 degrees Celsius) were virtually identical to long-term averages from nearby National Weather Service stations. Solar radiation averaged 65

  19. CONTAINMENT OF LOW-LEVEL RADIOACTIVE WASTE AT THE DOE SALTSTONE DISPOSAL FACILITY

    SciTech Connect

    Jordan, J.; Flach, G.

    2012-03-29

    As facilities look for permanent storage of toxic materials, they are forced to address the long-term impacts to the environment as well as any individuals living in affected area. As these materials are stored underground, modeling of the contaminant transport through the ground is an essential part of the evaluation. The contaminant transport model must address the long-term degradation of the containment system as well as any movement of the contaminant through the soil and into the groundwater. In order for disposal facilities to meet their performance objectives, engineered and natural barriers are relied upon. Engineered barriers include things like the design of the disposal unit, while natural barriers include things like the depth of soil between the disposal unit and the water table. The Saltstone Disposal Facility (SDF) at the Savannah River Site (SRS) in South Carolina is an example of a waste disposal unit that must be evaluated over a timeframe of thousands of years. The engineered and natural barriers for the SDF allow it to meet its performance objective over the long time frame. Some waste disposal facilities are required to meet certain standards to ensure public safety. These type of facilities require an engineered containment system to ensure that these requirements are met. The Saltstone Disposal Facility (SDF) at the Savannah River Site (SRS) is an example of this type of facility. The facility is evaluated based on a groundwater pathway analysis which considers long-term changes to material properties due to physical and chemical degradation processes. The facility is able to meet these performance objectives due to the multiple engineered and natural barriers to contaminant migration.

  20. Project report: Tritiated oil repackaging highlighting the ISMS process. Historical radioactive and mixed waste disposal request validation and waste disposal project

    SciTech Connect

    Schriner, J.A.

    1998-08-01

    The Integrated Safety Management System (ISMS) was established to define a framework for the essential functions of managing work safely. There are five Safety Management Functions in the model of the ISMS process: (1) work planning, (2) hazards analysis, (3) hazards control, (4) work performance, and (5) feedback and improve. Recent activities at the Radioactive and Mixed Waste Management Facility underscored the importance and effectiveness of integrating the ISMS process to safely manage high-hazard work with a minimum of personnel in a timely and efficient manner. This report describes how project personnel followed the framework of the ISMS process to successfully repackage tritium-contaminated oils. The main objective was to open the boxes without allowing the gaseous tritium oxide, which had built up inside the boxes, to release into the sorting room. The boxes would be vented out the building stack until tritium concentration levels were acceptable. The carboys would be repackaged into 30-gallon drums and caulked shut. Sealing the drums would decrease the tritium off-gassing into the RMWMF.

  1. Disposal of high-level radioactive wastes in the unsaturated zone: Technical considerations and response to comments

    NASA Astrophysics Data System (ADS)

    Hackbarth, C. J.; Nicholson, T. J.; Evans, D. D.

    1985-10-01

    On July 22, 1985, the U. S. Nuclear Regulatory Commission (NRC) promulgated amendments to 10 CFR Part 60 concerning disposal of high level radioactive waste (HLW) in geologic repositories in the unsaturated zone (50 FR 29641). The principal technical issues considered by the NRC staff during the development of these amendments was discussed. Certain technical discussions originally presented in draft NUREG-1046 were revised based on public comment letters and an increasing understanding of the physical, geochemical, and hydrological processes operative in unsaturated geologic media. The following issues related to disposal of HLW within the unsaturated zone were discussed: hydrogeologic properties and conditions, heat dissipation and temperature, geochemistry, retrievability, potential for exhumation of the radioactive waste by natural causes and by human intrusion, the effects of future climatic changes on the level of the regional water table, and transport of radionuclides in the gaseous state. On July 22, 1985, the U. S. Nuclear Regulatory Commission (NRC) promulgated amendments to 10 CFR meter depth for waste emplacement, limitations on exploratory boreholes, backfill requirements, waste package design criteria, and provisions for ventilation.

  2. Implementing Geological Disposal of Radioactive Waste Technology Platform From the Strategic Research Agenda to its Deployment - 12015

    SciTech Connect

    Ouzounian, P.; Palmu, Marjatta; Eng, Torsten

    2012-07-01

    Several European waste management organizations (WMOs) have initiated a technology platform for accelerating the implementation of deep geological disposal of radioactive waste in Europe. The most advanced waste management programmes in Europe (i.e. Finland, Sweden, and France) have already started or are prepared to start the licensing process of deep geological disposal facilities within the next decade. A technology platform called Implementing Geological Disposal of Radioactive Waste Technology Platform (IGD-TP) was launched in November 2009. A shared vision report for the platform was published stating that: 'Our vision is that by 2025, the first geological disposal facilities for spent fuel, high-level waste, and other long-lived radioactive waste will be operating safely in Europe'. In 2011, the IGD-TP had eleven WMO members and about 70 participants from academia, research, and the industry committed to its vision. The IGD-TP has started to become a tool for reducing overlapping work, to produce savings in total costs of research and implementation and to make better use of existing competence and research infrastructures. The main contributor to this is the deployment of the IGD-TP's newly published Strategic Research Agenda (SRA). The work undertaken for the SRA defined the pending research, development and demonstration (RD and D) issues and needs. The SRA document describing the identified issues that could be worked on collaboratively was published in July 2011. It is available on the project's public web site (www.igdtp.eu). The SRA was organized around 7 Key Topics covering the Safety Case, Waste forms and their behaviour, Technical feasibility and long-term performance of repository components, Development strategy of the repository, Safety of construction and operations, Monitoring, and Governance and stakeholder involvement. Individual Topics were prioritized within the Key Topics. Cross-cutting activities like Education and Training or Knowledge

  3. Special Analysis for the Disposal of the Lawrence Livermore National Laboratory Low Activity Beta/Gamma Sources Waste Stream at the Area 5 Radioactive Waste Management Site, Nevada National Security Site, Nye County, Nevada

    SciTech Connect

    Shott, Gregory J.

    2015-06-01

    This special analysis (SA) evaluates whether the Lawrence Livermore National Laboratory (LLNL) Low Activity Beta/Gamma Sources waste stream (BCLALADOEOSRP, Revision 0) is suitable for disposal by shallow land burial (SLB) at the Area 5 Radioactive Waste Management Site (RWMS) at the Nevada National Security Site (NNSS). The LLNL Low Activity Beta/Gamma Sources waste stream consists of sealed sources that are no longer needed. The LLNL Low Activity Beta/Gamma Sources waste stream required a special analysis because cobalt-60 (60Co), strontium-90 (90Sr), cesium-137 (137Cs), and radium-226 (226Ra) exceeded the NNSS Waste Acceptance Criteria (WAC) Action Levels (U.S. Department of Energy, National Nuclear Security Administration Nevada Field Office [NNSA/NFO] 2015). The results indicate that all performance objectives can be met with disposal of the LLNL Low Activity Beta/Gamma Sources in a SLB trench. The LLNL Low Activity Beta/Gamma Sources waste stream is suitable for disposal by SLB at the Area 5 RWMS. However, the activity concentration of 226Ra listed on the waste profile sheet significantly exceeds the action level. Approval of the waste profile sheet could potentially allow the disposal of high activity 226Ra sources. To ensure that the generator does not include large 226Ra sources in this waste stream without additional evaluation, a control is need on the maximum 226Ra inventory. A limit based on the generator’s estimate of the total 226Ra inventory is recommended. The waste stream is recommended for approval with the control that the total 226Ra inventory disposed shall not exceed 5.5E10 Bq (1.5 Ci).

  4. Historical Relationship Between Performance Assessment for Radioactive Waste Disposal and Other Types of Risk Assessment in the United States

    SciTech Connect

    RECHARD,ROBERT P.

    2000-07-14

    This paper describes the evolution of the process for assessing the hazards of a geologic disposal system for radioactive waste and, similarly, nuclear power reactors, and the relationship of this process with other assessments of risk, particularly assessments of hazards from manufactured carcinogenic chemicals during use and disposal. This perspective reviews the common history of scientific concepts for risk assessment developed to the 1950s. Computational tools and techniques developed in the late 1950s and early 1960s to analyze the reliability of nuclear weapon delivery systems were adopted in the early 1970s for probabilistic risk assessment of nuclear power reactors, a technology for which behavior was unknown. In turn, these analyses became an important foundation for performance assessment of nuclear waste disposal in the late 1970s. The evaluation of risk to human health and the environment from chemical hazards is built upon methods for assessing the dose response of radionuclides in the 1950s. Despite a shared background, however, societal events, often in the form of legislation, have affected the development path for risk assessment for human health, producing dissimilarities between these risk assessments and those for nuclear facilities. An important difference is the regulator's interest in accounting for uncertainty and the tools used to evaluate it.

  5. Contributions to the disposal of highly radioactive reactor wastes in space

    NASA Astrophysics Data System (ADS)

    Promoli, Erwin

    A specific cost function of nuclear wastes disposal in space was deduced using payload models for the upper Earth orbits. An engineering estimate shows that the allowed temperatures in compact disposals of several million tons, consisting of single containers, are not exceeded. The investigation of the natural attitude stability shows that a stable attitude can easily be maintained. It is found that for heights above 500 km, the orbit life expectation exceeds that of the Earth. For lower heights, an attitude hold is feasible by a constant propulsion with the lowest thrust. For the lowest orbits the costs are too high. The cost-optimized height is in the range of 500 km. Comparison between the risks of the disposal on Earth and in space shows that the global risk of both variants is comparable, due to the complementary risks on Earth, such as reprocessing, recovery, etc.

  6. Method and apparatus for extracting tritium and preparing radioactive waste for disposal

    DOEpatents

    Heung, Leung K.

    1994-01-01

    Apparatus for heating an object such as a nuclear target bundle to release and recover hydrogen and contain the disposable residue for disposal. The apparatus comprises an inverted furnace, a sleeve/crucible assembly for holding and enclosing the bundle, conveying equipment for placing the sleeve onto the crucible and loading the bundle into the sleeve/crucible, a lift for raising the enclosed bundle into the furnace, and hydrogen recovery equipment including a trap and strippers, all housed in a containment having negative internal pressure. The crucible/sleeve assembly has an internal volume that is sufficient to enclose and hold the bundle before heating; the crucible's internal volume is sufficient by itself to hold and enclose the bundle's volume after heating. The crucible can then be covered and disposed of; the sleeve, on the other hand, can be reused.

  7. Method and apparatus for extracting tritium and preparing radioactive waste for disposal

    DOEpatents

    Heung, L.K.

    1994-03-29

    Apparatus is described for heating an object such as a nuclear target bundle to release and recover hydrogen and contain the disposable residue for disposal. The apparatus comprises an inverted furnace, a sleeve/crucible assembly for holding and enclosing the bundle, conveying equipment for placing the sleeve onto the crucible and loading the bundle into the sleeve/crucible, a lift for raising the enclosed bundle into the furnace, and hydrogen recovery equipment including a trap and strippers, all housed in a containment having negative internal pressure. The crucible/sleeve assembly has an internal volume that is sufficient to enclose and hold the bundle before heating; the crucible's internal volume is sufficient by itself to hold and enclose the bundle's volume after heating. The crucible can then be covered and disposed of; the sleeve, on the other hand, can be reused. 4 figures.

  8. Subsurface disposal of liquid low-level radioactive wastes at Oak Ridge, Tennessee

    SciTech Connect

    Stow, S.H.; Haase, C.S.

    1986-01-01

    At Oak Ridge National Laboratory (ORNL) subsurface injection has been used to dispose of low-level liquid nuclear waste for the last two decades. The process consists of mixing liquid waste with cement and other additives to form a slurry that is injected under pressure through a cased well into a low-permeability shale at a depth of 300 m. The slurry spreads from the injection well along bedding plane fractures and forms solid grout sheets of up to 200 m in radius. Using this process, ORNL has disposed of over 1.5 x 10/sup 6/ Ci of activity; the principal nuclides are /sup 90/Sr and /sup 137/Cs. In 1982, a new injection facility was put into operation. Each injection, which lasts some two days, results in the emplacement of approximately 750,000 liters of slurry. Disposal cost per liter is about $0.30, including capital costs of the facility. This subsurface disposal process is fundamentally different from other operations. Wastes are injected into a low-permeability aquitard, and the process is designed to isolate nuclides, preventing dispersion in groundwaters. The porosity into which wastes are injected is created by hydraulically fracturing the host formation along bedding planes. Investigations are under way to determine the long-term hydrologic isolation of the injection zone and the geochemical impact of saline groundwater on nuclide mobility. Injections are monitored by gamma-ray logging of cased observation wells to determine grout sheet orientation after an injection. Recent monitoring work has involved the use of tiltmeters, surface uplift surveys, and seismic arrays. Recent regulatory constraints may cause permanent cessation of the operation. Federal and state statutes, written for other types of injection facilities, impact the ORNL facility. This disposal process, which may have great applicability for disposal of many wastes, including hazardous wastes, may not be developed for future use.

  9. The Environmental Agency's Assessment of the Post-Closure Safety Case for the BNFL DRIGG Low Level Radioactive Waste Disposal Facility

    SciTech Connect

    Streatfield, I. J.; Duerden, S. L.; Yearsley, R. A.

    2002-02-26

    The Environment Agency is responsible, in England and Wales, for authorization of radioactive waste disposal under the Radioactive Substances Act 1993. British Nuclear Fuels plc (BNFL) is currently authorized by the Environment Agency to dispose of solid low level radioactive waste at its site at Drigg, near Sellafield, NW England. As part of a planned review of this authorization, the Environment Agency is currently undertaking an assessment of BNFL's Post-Closure Safety Case Development Programme for the Drigg disposal facility. This paper presents an outline of the review methodology developed and implemented by the Environment Agency specifically for the planned review of BNFL's Post-Closure Safety Case. The paper also provides an overview of the Environment Agency's progress in its on-going assessment programme.

  10. Nuclear energy and radioactive waste disposal in the age of recycling

    SciTech Connect

    Conca, James L.; Apted, Michael

    2007-07-01

    The magnitude of humanity's energy needs requires that we embrace a multitude of various energy sources and applications. For a variety of reasons, nuclear energy must be a major portion of the distribution, at least one third. The often-cited strategic hurdle to this approach is nuclear waste disposal. Present strategies concerning disposal of nuclear waste need to be changed if the world is to achieve both a sustainable energy distribution by 2040 and solve the largest environmental issue of the 21. century - global warming. It is hoped that ambitious proposals to replace fossil fuel power generation by alternatives will drop the percentage of fossil fuel use substantially, but the absolute amount of fossil fuel produced electricity must be kept at or below its present 10 trillion kW-hrs/year. Unfortunately, the rapid growth in consumption to over 30 trillion kW-hrs/year by 2040, means that 20 trillion kW-hrs/yr of non-fossil fuel generated power has to come from other sources. If half of that comes from alternative non-nuclear, non-hydroelectric sources (an increase of 3000%), then nuclear still needs to increase by a factor of four worldwide to compensate. Many of the reasons nuclear energy did not expand after 1970 in North America (proliferation, capital costs, operational risks, waste disposal, and public fear) are no longer a problem. The WIPP site in New Mexico, an example of a solution to the nuclear waste disposal issue, and also to public fear, is an operating deep geologic nuclear waste repository in the massive bedded salt of the Salado Formation. WIPP has been operating for eight years, and as of this writing, has disposed of over 50,000 m{sup 3} of transuranic waste (>100 nCi/g but <23 Curie/liter) including high activity waste. The Salado Formation is an ideal host for any type of nuclear waste, especially waste from recycled spent fuel. (authors)

  11. Feasibility of space disposal of radioactive nuclear waste. 1: Executive summary

    NASA Technical Reports Server (NTRS)

    1973-01-01

    This NASA study, performed at the request of the AEC, concludes that transporting radioactive waste (primarily long-lived isotopes) into space is feasible. Tentative solutions are presented for technical problems involving safe packaging. Launch systems (existing and planned), trajectories, potential hazards, and various destinations were evaluated. Solar system escape is possible and would have the advantage of ultimate removal of the radioactive waste from man's environment. Transportation costs would be low (comparable to less than a 5 percent increase in the cost of electricity) even though more than 100 space shuttle launches per year would be required by the year 2000.

  12. Validation of predictive models for geologic disposal of radioactive waste via natural analogs

    SciTech Connect

    Cohen, J.J.; Smith, C.F.

    1981-03-01

    The incorporation of toxic or hazardous material in the earth's crust is a phenomenon not unique to radioactive waste burial. Useful insights on the environmental transport and effects of underground toxic or radioactive material can be derived from comparative analysis against natural (mineral) analogs. This paper includes a discussion of the background and rationale for the analog approach, a descripton of several variations of the approach, and some sample applications to illustrate the concept, focusing on Radium-226 and Iodine-129 as specific case studies.

  13. Public acceptance activities for the development of new commercial low-level radioactive waste disposal capacity in the United States of America

    SciTech Connect

    Ozaki, C.B.; Scott, R.L.

    1993-12-31

    In the US, the states are responsible for providing disposal capability for commercial low-level radioactive waste generated within their borders. Public acceptance of state activities toward developing this capability is a key factor in the ultimate success of state efforts. The states are using several different approaches to gain public acceptance for the location and development of new low-level radioactive waste disposal facilities. This presentation describes state efforts to gain public acceptance for siting and developing activities and discusses the lessons learned from these state experiences.

  14. Seals and Sealing Techniques

    NASA Technical Reports Server (NTRS)

    1972-01-01

    Developments by the aerospace industry in seals and sealing techniques are announced for possible use in other areas. The announcements presented are grouped as: sealing techniques for cryogenic fluids, high pressure applications, and modification for improved performance.

  15. Opportunities for Cost Effective Disposal of Radioactively Contaminated Solid Waste on the Oak Ridge Reservation, Oak Ridge, TN - 13045

    SciTech Connect

    DeMonia, Brian; Dunning, Don; Hampshire John

    2013-07-01

    Department of Energy (DOE) requirements for the release of non-real property, including solid waste, containing low levels of residual radioactive materials are specified in DOE Order 458.1 and associated guidance. Authorized limits have been approved under the requirements of DOE Order 5400.5, predecessor to DOE Order 458.1, to permit disposal of solid waste containing low levels of residual radioactive materials at solid waste landfills located within the DOE Oak Ridge Reservation (ORR). Specifically, volumetric concentration limits for disposal of solid waste at Industrial Landfill V and at Construction/Demolition Landfill VII were established in 2003 and 2007, respectively, based on the requirements in effect at that time, which included: an evaluation to ensure that radiation doses to the public would not exceed 25 mrem/year and would be as low as reasonably achievable (ALARA), with a goal of a few mrem/year or less (in fact, these authorized limits actually were derived to meet a dose constraint of 1 mrem/year); an evaluation of compliance with groundwater protection requirements; and reasonable assurance that the proposed disposal is not likely to result in a future requirement for remediation of the landfill. Prior to approval as DOE authorized limits, these volumetric concentration limits were coordinated with the Tennessee Department of Environment and Conservation (TDEC) and documented in a Memorandum of Understanding (MOU) between the TDEC Division of Radiological Health and the TDEC Division of Solid Waste Management. These limits apply to the disposal of soil and debris waste generated from construction, maintenance, environmental restoration, and decontamination and decommissioning (D and D) activities on the DOE Oak Ridge Reservation. The approved site-specific authorized limits were incorporated in the URS/CH2M Oak Ridge LLC (UCOR) waste profile system that authorizes disposal of special wastes at either of the RCRA Subtitle D landfills. However, a

  16. Thermomechanical analysis of some proposed schemes for radioactive waste disposal. Research report

    SciTech Connect

    Carter, J.P.; Booker, J.R.

    1985-09-01

    Solutions are presented for the steady-state, thermomechanical response of an elastic half space containing either a vertical line source or a horizontal disc-shaped source of heat. It is suggested that these solutions may be useful for predicting the long-term behavior of rock masses containing nuclear-waste repositories; the solution for the line source being appropriate for the disposal of hot wastes in deep boreholes and the solution for the disc-shaped source being applicable to disposal in underground galleries of significant lateral extent. It is demonstrated that, in both cases, the surface of the rock mass will heave and that there is potential for cracking of the rock overlying the repositories because of tensile stress changes induced in the region near the surface. Typical values of these quantities were calculated for a rock-mass-like granite.

  17. Study of extraterrestrial disposal of radioactive wastes. Part 2: Preliminary feasibility screening study of extraterrestrial disposal of radioactive wastes in concentrations, matrix materials, and containers designed for storage on earth

    NASA Technical Reports Server (NTRS)

    Hyland, R. E.; Wohl, M. L.; Thompson, R. L.; Finnegan, P. M.

    1972-01-01

    The results are reported of a preliminary feasibility screening study for providing long-term solutions to the problems of handling and managing radioactive wastes by extraterrestrial transportation of the wastes. Matrix materials and containers are discussed along with payloads, costs, and destinations for candidate space vehicles. The conclusions reached are: (1) Matrix material such as spray melt can be used without exceeding temperature limits of the matrix. (2) The cost in mills per kw hr electric, of space disposal of fission products is 4, 5, and 28 mills per kw hr for earth escape, solar orbit, and solar escape, respectively. (3) A major factor effecting cost is the earth storage time. Based on a normal operating condition design for solar escape, a storage time of more than sixty years is required to make the space disposal charge less than 10% of the bus-bar electric cost. (4) Based on a 10 year earth storage without further processing, the number of shuttle launches required would exceed one per day.

  18. Subsurface disposal of liquid low-level radioactive wastes at Oak Ridge, Tennessee

    SciTech Connect

    Stow, S.H.; Haase, C.S.

    1986-01-01

    At Oak Ridge National Laboratory (ORNL) subsurface injection has been used to dispose of low-level liquid nuclear waste for the last two decades. The process consists of mixing liquid waste with cement and other additives to form a slurry that is injected under pressure through a cased well into a low-permeability shale at a depth of 300 m (1000 ft). The slurry spreads from the injection well along bedding plane fractures and forms solid grout sheets of up to 200 m (660 ft) in radius. Using this process, ORNL has disposed of over 1.5 x 10/sup 6/ Ci of activity; the principal nuclides are /sup 90/Sr and /sup 137/Cs. In 1982, a new injection facility was put into operation. Each injection, which lasts some two days, results in the emplacement of approximately 750,000 l (180,000 gal) of slurry. Disposal cost per liter is approximately $0.30, including capital costs of the facility. This subsurface disposal process is fundamentally different from other operations. Wastes are injected into a low-permeability aquitard, and the process is designed to isolate nuclides, preventing dispersion in groundwaters. The porosity into which wastes are injected is created by hydraulically fracturing the host formation along bedding planes. The site is in the structurally complex Valley and Ridge Province. The stratigraphy consists of lower Paleozoic rocks. Investigations are under way to determine the long-term hydrologic isolation of the injection zone and the geochemical impact of saline groundwater on nuclide mobility. Injections are monitored by gamma-ray logging of cased observation wells to determine grout sheet orientation after an injection. Recent monitoring work has involved the use of tiltmeters, surface uplift surveys, and seismic arrays. 26 refs., 7 figs.

  19. Long-term criticality control in radioactive waste disposal facilities using depleted uranium

    SciTech Connect

    Forsberg, C.W.

    1997-02-19

    Plant photosynthesis has created a unique planetary-wide geochemistry - an oxidizing atmosphere with oxidizing surface waters on a planetary body with chemically reducing conditions near or at some distance below the surface. Uranium is four orders of magnitude more soluble under chemically oxidizing conditions than it is under chemically reducing conditions. Thus, uranium tends to leach from surface rock and disposal sites, move with groundwater, and concentrate where chemically reducing conditions appear. Earth`s geochemistry concentrates uranium and can separate uranium from all other elements except oxygen, hydrogen (in water), and silicon (silicates, etc). Fissile isotopes include {sup 235}U, {sup 233}U, and many higher actinides that eventually decay to one of these two uranium isotopes. The potential for nuclear criticality exists if the precipitated uranium from disposal sites has a significant fissile enrichment, mass, and volume. The earth`s geochemistry suggests that isotopic dilution of fissile materials in waste with {sup 238}U is a preferred strategy to prevent long-term nuclear criticality in and beyond the boundaries of waste disposal facilities because the {sup 238}U does not separate from the fissile uranium isotopes. Geological, laboratory, and theoretical data indicate that the potential for nuclear criticality can be minimized by diluting fissile materials with-{sup 238}U to 1 wt % {sup 235}U equivalent.

  20. Issues in the review of a license application for an above grade low-level radioactive waste disposal facility

    SciTech Connect

    Ringenberg, J.D.

    1993-03-01

    In December 1987, Nebraska was selected by the Central Interstate Compact (CIC) Commission as the host state for the construction of a low-level radioactive waste disposal facility. After spending a year in the site screening process, the Compact`s developer, US Ecology, selected three sites for detailed site characterization. These sites were located in Nemaha, Nuckolls and Boyd Counties. One year later the Boyd County site was selected as the preferred site and additional site characterization studies were undertaken. On July 29, 1990, US Ecology submitted a license application to the Nebraska Department of Environmental Control (now Department of Environmental Quality-NDEQ). This paper will present issues that the NDEQ has dealt with since Nebraska`s selection as the host state for the CIC facility.

  1. Corrosion considerations of high-nickel alloys and titanium alloys for high-level radioactive waste disposal containers

    SciTech Connect

    Gdowski, G.E.; McCright, R.D.

    1991-07-01

    Corrosion resistant materials are being considered for the metallic barrier of the Yucca Mountain Project`s high-level radioactive waste disposal containers. High nickel alloys and titanium alloys have good corrosion resistance properties and are considered good candidates for the metallic barrier. The localized corrosion phenomena, pitting and crevice corrosion, are considered as potentially limiting for the barrier lifetime. An understanding of the mechanisms of localized corrosion of how various parameters affect it will be necessary for adequate performance assessments of candidate container materials. Examples of some of the concerns involving candidate container materials. Examples of some of the concerns of involving localized corrosion are discussed. The effects of various parameters, such as temperature and concentration of halide species, on localized corrosion are given. In addition concerns about aging of the protective oxide layer in the expected service temperature range (50 to 250{degrees}C) are presented. Also some mechanistic considerations of localized corrosion are given. 31 refs., 1 tab.

  2. Hydrologic data for the Weldon Spring radioactive waste-disposal sites, St. Charles County, Missouri; 1984-1986

    USGS Publications Warehouse

    Kleeschulte, M.J.; Emmett, L.F.; Barks, J.H.

    1986-01-01

    Hydrologic and water quality data were collected during an investigation of the Weldon Spring radioactive waste disposal sites and surroundings area in St. Charles County, Missouri, from 1984 to 1986. The data consists of water quality analyses of samples collected from 45 groundwater and 27 surface water sites. This includes analyses of water from four raffinate pits and from the Weldon Spring quarry. Also included in the report are the results of a seepage run on north flowing tributaries to Dardenne Creek from Kraut Run to Crooked Creek. Mean daily discharge from April 1985 to April 1986 is given for two springs located about 1.5 mi north of the chemical plant. (USGS)

  3. Hydrogeology, ground-water flow, and tritium movement at low-level radioactive-waste disposal site near Sheffield, Illinois

    USGS Publications Warehouse

    Garklavs, George; Healy, R.W.

    1986-01-01

    Groundwater flow and tritium movement are described at and near a low-level radioactive waste disposal site near Sheffield, Illinois. Flow in the shallow aquifer is confined to three basins that ultimately drain into a stripmine lake. Most of the flow from the site is through a buried, pebbly sandfilled channel. Remaining flow is toward alluvium of an existing stream. Conceptual flow models for the two largest basins are used to improve definition of flow velocity and direction. Flow velocities range from about 25 to 2,500 ft/yr. Tritium was found in all three basins. The most extensive migration of tritium is coincident with buried channel. Tritium concentrations ranged from detection level to more than 300 nanocuries/L. (USGS)

  4. Comparative assessment of status and opportunities for carbon Dioxide Capture and storage and Radioactive Waste Disposal In North America

    SciTech Connect

    Oldenburg, C.; Birkholzer, J.T.

    2011-07-22

    Aside from the target storage regions being underground, geologic carbon sequestration (GCS) and radioactive waste disposal (RWD) share little in common in North America. The large volume of carbon dioxide (CO{sub 2}) needed to be sequestered along with its relatively benign health effects present a sharp contrast to the limited volumes and hazardous nature of high-level radioactive waste (RW). There is well-documented capacity in North America for 100 years or more of sequestration of CO{sub 2} from coal-fired power plants. Aside from economics, the challenges of GCS include lack of fully established legal and regulatory framework for ownership of injected CO{sub 2}, the need for an expanded pipeline infrastructure, and public acceptance of the technology. As for RW, the USA had proposed the unsaturated tuffs of Yucca Mountain, Nevada, as the region's first high-level RWD site before removing it from consideration in early 2009. The Canadian RW program is currently evolving with options that range from geologic disposal to both decentralized and centralized permanent storage in surface facilities. Both the USA and Canada have established legal and regulatory frameworks for RWD. The most challenging technical issue for RWD is the need to predict repository performance on extremely long time scales (10{sup 4}-10{sup 6} years). While attitudes toward nuclear power are rapidly changing as fossil-fuel costs soar and changes in climate occur, public perception remains the most serious challenge to opening RW repositories. Because of the many significant differences between RWD and GCS, there is little that can be shared between them from regulatory, legal, transportation, or economic perspectives. As for public perception, there is currently an opportunity to engage the public on the benefits and risks of both GCS and RWD as they learn more about the urgent energy-climate crisis created by greenhouse gas emissions from current fossil-fuel combustion practices.

  5. 3D surface roughness recreation and data processing of granitic rocks and claystones, potential host rocks for radioactive waste disposal

    NASA Astrophysics Data System (ADS)

    Buocz, Ildikó; Török, Ákos; Rozgonyi-Boissinot, Nikoletta

    2015-04-01

    The determination and modelling of the stability of rock slopes, tunnels, or underground spaces, i.e. radioactive waste disposal facilities, is an important task in engineering. The appropriate estimation of the mechanical parameters for a realistic description of the behaviour of rocks results in higher safety and more economic design. The failure of stability is primarily due to the shear failure of the rock masses along fractures and joints: therefore the correct determination of the shear strength is crucial. One of the most important parameters influencing the shear strength along rock joints is their surface roughness. Although the quantification of surface roughness has been an open question during the past century, several attempts have been made, starting with 2D and continuing with 3D measurements, to provide engineers with a method for determining shear strength numerically. As technology evolved, the 3D methods became more popular and several scientists started to investigate the surface properties through laser scanning and different photogrammetrical methods. This paper shows a photogrammetric method for the 3D digital recreation of joint surfaces of granitic rock and claystone, both potential host rocks for radioactive waste disposal. The rocks derived from Bátaapáti (South Hungary) and Mont Terri (North Switzerland) respectively. The samples are laboratory scaled specimens with an areal size of 50x50 mm. The software used is called ShapeMetrix3D, developed by 3GSM GmbH in Austria. The major steps of the creation of the 3D picture are presented, as well as the following data processing which leads to the quantification of the 3D surface roughness.

  6. Remote Sensing Analysis of the Sierra Blanca (Faskin Ranch) Low-Level Radioactive Waste Disposal Site, Hudspeth County, Texas

    SciTech Connect

    LeMone, D. V.; Dodge, R.; Xie, H.; Langford, R. P.; Keller, G. R.

    2002-02-26

    Remote sensing images provide useful physical information, revealing such features as geological structure, vegetation, drainage patterns, and variations in consolidated and unconsolidated lithologies. That technology has been applied to the failed Sierra Blanca (Faskin Ranch) shallow burial low-level radioactive waste disposal site selected by the Texas Low-Level Radioactive Waste Disposal Authority. It has been re-examined using data from LANDSAT satellite series. The comparison of the earlier LANDSAT V (5/20/86) (30-m resolution) with the later new, higher resolution ETM imagery (10/23/99) LANDSAT VII data (15-m resolution) clearly shows the superiority of the LANDSAT VII data. The search for surficial indications of evidence of fatal flaws at the Sierra Blanca site utilizing was not successful, as it had been in the case of the earlier remote sensing analysis of the failed Fort Hancock site utilizing LANDSAT V data. The authors conclude that the tectonic activity at the Sierra Blanca site is much less recent and active than in the previously studied Fort Hancock site. The Sierra Blanca site failed primarily on the further needed documentation concerning a subsurface fault underneath the site and environmental justice issues. The presence of this fault was not revealed using the newer LANDSAT VII data. Despite this fact, it must be remembered that remote sensing provides baseline documentation for determining future physical and financial remediation responsibilities. On the basis of the two sites examined by LANDSAT remote sensing imaging, it is concluded that it is an essential, cost-effective tool that should be utilized not only in site examination but also in all nuclear-related facilities.

  7. Treatment of uncertainty and developing conceptual models for environmental risk assessments and radioactive waste disposal safety cases.

    PubMed

    El-Ghonemy, Hamdi; Watts, Len; Fowler, Linda

    2005-01-01

    The common approach to performing quantitative risk assessments in the contaminated land industry in the UK lacks a formal methodology for the treatment of the full range of uncertainties and for documenting decisions regarding the development of conceptual models and the selection of computer codes. The approach presented here represents an alternative, more detailed, and systematic approach for developing conceptual models and addressing uncertainties when undertaking contaminated land risk assessments. It is intended that the advantages of this approach are recognised by practitioners in the contaminated land industry and adopted, where appropriate, to help improve the quality of contaminated land risk assessments. The identification of features, events, and processes (FEPs) has been applied to safety assessments of deep geological and near-surface disposal of radioactive wastes. One of the primary benefits of using this approach is in the development of conceptual models. The approach identifies the FEPs that need to be addressed during the development of conceptual models and in the selection of suitable computer codes that can be used to represent the conceptual models. This approach has been applied by BNFL at the low-level radioactive waste disposal site at Drigg in Cumbria and is currently being adopted for a contaminated land study at the Sellafield site, also in Cumbria. This paper presents the advantages of using FEPs in the development of conceptual models and the treatment of uncertainties. The paper also discusses the application of this approach to contaminated land studies and provides an example to demonstrate the application of the approach. BNFL's approach at the Drigg site involves the identification of components (features) and phenomena (events and processes) that govern interactions and dependencies between the components by arranging them in a matrix format. PMID:15607782

  8. Status of the North Carolina/Southeast Compact low-level radioactive waste disposal project

    SciTech Connect

    Walker, C.K.

    1993-03-01

    The Southeast Compact is a sited region for low-level radioactive waste because of the current facility at Barnwell, South Carolina. North Carolina has been designated as the next host state for the compact, and the North Carolina Low-Level Radioactive Waste Management Authority is the agency charged with developing the new facility. Chem-Nuclear Systems, Inc., has been selected by the Authority as its primary site development and operations contractor. This paper will describe the progress currently being made toward the successful opening of the facility in January 1996. The areas to be addressed include site characterization, performance assessment, facility design, public outreach, litigation, finances, and the continued operation of the Barnwell facility.

  9. Radionuclide concentrations in/on vegetation at radioactive-waste disposal Area G during the 1995 growing season. Progress report

    SciTech Connect

    Fresquez, P.R.; Vold, E.L.; Naranjo, L. Jr.

    1996-03-01

    Overstory (pinon pine) and understory (grass and forb) vegetation were collected within and around selected points at Area G--a low- level radioactive solid-waste disposal facility at Los Alamos National Laboratory--for the analysis of tritium ({sup 3}H), strontium ({sup 90}Sr), plutonium ({sup 238}Pu and {sup 239}Pu), cesium ({sup 137}Cs), and total uranium. Also, heavy metals (Ag, As, Ba, Be, Cd, Cr, Hg, Ni, Pb, Sb, Se, and Tl) in/on vegetation were determined. In general, most (unwashed) vegetation collected within and around Area G contained {sup 3}H, uranium, {sup 238}Pu, and {sup 239}Pu in higher concentrations than vegetation collected from background areas. Tritium, in particular, was detected as high as 7300 pCi mL{sup -1} in understory vegetation collected from the west side of the transuranic (TRU) pads. The south and west ends of the tritium shaft field also contained elevated levels of {sup 3}H in overstory, and especially in understory vegetation, as compared to background; this suggests that {sup 3}H may be migrating from this waste repository through surface and subsurface pathways. Also, understory vegetation collected north of the TRU pads (adjacent to the fence line of Area G) contained the highest values of {sup 238}Pu and {sup 239}Pu as compared to background, and may be a result of surface holding, storage, and/or disposal activities.

  10. Mechanical environmental transport of actinides and ¹³⁷Cs from an arid radioactive waste disposal site.

    PubMed

    Snow, Mathew S; Clark, Sue B; Morrison, Samuel S; Watrous, Matthew G; Olson, John E; Snyder, Darin C

    2015-10-01

    Aeolian and pluvial processes represent important mechanisms for the movement of actinides and fission products at the Earth's surface. Soil samples taken in the early 1970's near a Department of Energy radioactive waste disposal site (the Subsurface Disposal Area, SDA, located in southeastern Idaho) provide a case study for studying the mechanisms and characteristics of environmental actinide and (137)Cs transport in an arid environment. Multi-component mixing models suggest actinide contamination within 2.5 km of the SDA can be described by mixing between 2 distinct SDA end members and regional nuclear weapons fallout. The absence of chemical fractionation between (241)Am and (239+240)Pu with depth for samples beyond the northeastern corner and lack of (241)Am in-growth over time (due to (241)Pu decay) suggest mechanical transport and mixing of discrete contaminated particles under arid conditions. Occasional samples northeast of the SDA (the direction of the prevailing winds) contain anomalously high concentrations of Pu with (240)Pu/(239)Pu isotopic ratios statistically identical to those in the northeastern corner. Taken together, these data suggest flooding resulted in mechanical transport of contaminated particles into the area between the SDA and a flood containment dike in the northeastern corner, following which subsequent contamination spreading in the northeastern direction resulted from wind transport of discrete particles. PMID:26107287

  11. Hydrologic evaluation methodology for estimating water movement through the unsaturated zone at commercial low-level radioactive waste disposal sites

    SciTech Connect

    Meyer, P.D.; Rockhold, M.L.; Nichols, W.E.; Gee, G.W.

    1996-01-01

    This report identifies key technical issues related to hydrologic assessment of water flow in the unsaturated zone at low-level radioactive waste (LLW) disposal facilities. In addition, a methodology for incorporating these issues in the performance assessment of proposed LLW disposal facilities is identified and evaluated. The issues discussed fall into four areas: estimating the water balance at a site (i.e., infiltration, runoff, water storage, evapotranspiration, and recharge); analyzing the hydrologic performance of engineered components of a facility; evaluating the application of models to the prediction of facility performance; and estimating the uncertainty in predicted facility performance. To illustrate the application of the methodology, two examples are presented. The first example is of a below ground vault located in a humid environment. The second example looks at a shallow land burial facility located in an arid environment. The examples utilize actual site-specific data and realistic facility designs. The two examples illustrate the issues unique to humid and arid sites as well as the issues common to all LLW sites. Strategies for addressing the analytical difficulties arising in any complex hydrologic evaluation of the unsaturated zone are demonstrated.

  12. Distribution of gases in the unsaturated zone at a low-level radioactive-waste disposal site near Sheffield, Illinois

    USGS Publications Warehouse

    Striegl, Robert G.

    1988-01-01

    The unsaturated zone is a medium that provides pneumatic communication for the movement of gases from wastes buried in landfills to the atmosphere, biota, and groundwater. Gases in unsaturated glacial and eolian deposits near a waste-disposal trench at the low-level radioactive-waste disposal site near Sheffield, Bureau County, Illinois, were identified, and the spatial and temporal distributions of the partial pressures of those gases were determined for the period January 1984 through January 1986. Methods for the collection and analyses of the gases are described, as are geologic and hydrologic characteristics of the unsaturated zone that affect gas transport. The identified gases, which are of natural and of waste origin, include nitrogen, oxygen, and argon, carbon dioxide, methane, propane, butane, tritiated water vapor, 14carbon dioxide, and 222 radon. Concentrations of methane and 14carbon dioxide originated at the waste, as shown by partial-pressure gradients of the gases; 14carbon dioxide partial pressures exceeded natural background partial pressures by factors greater than 1 million at some locations. Variations in partial pressures of oxygen and carbon dioxide were seasonal among piezometers because of increased root and soil-microbe respiration during summer. Variations in methane and 14carbon dioxide partial pressures were apparently related to discrete releases from waste sources at unpredictable intervals of time. No greater than background partial pressures for tritiated water vapor or 222 radon were measured. (USGS)

  13. Geophysical studies at proposed low-level radioactive waste disposal sites in west Texas

    SciTech Connect

    Keller, G.R.; Doser, D.I.; Whitelaw, J.; Miller, K.C.; Hua, F.; Baker, M.R.; Meeks, N. )

    1994-03-01

    Although the disposal of high-level nuclear waste is officially a national problem, the federal government has charged each state with the responsibility of disposing of its own low-level nuclear waste. Texas has considered many possible areas for its disposal facility, but has studied two sites in Hudspeth County extensively. Geophysical methods have been used to study the subsurface structure of these sites, evaluate the earthquake hazards, and set up monitoring of possible leakage from the sites. The structural studies employed the same techniques as used in petroleum exploration, but with a ore balanced reliance between seismic and potential field methods. Since the scale of these investigations was relatively small (a few miles in extent), high-resolution methodology was employed. This aspect of the project mainly impacted the seismic reflection work. The depth to the bedrock was a major concern because the near-surface alluvium is generally a good natural barrier to any potential leakage. The location of any faults near the sites was also a major concern, because faults were both an indicator of potential earthquake hazards and a possible pathway for rapid movement of any material that might leak from the site. Analysis of the tectonic stability of the site involved regional geophysical data on a crustal scale and an evaluation of the historical earthquake record. A network of seismograph stations was established in the region to monitor contemporary seismicity. Compared to typical petroleum applications of geophysical data, these studies involved a wide variety of data and an analysis that required the methodical integration of these data.

  14. An Updated Performance Assessment For A New Low-Level Radioactive Waste Disposal Facility In West Texas - 12192

    SciTech Connect

    Dornsife, William P.; Kirk, J. Scott; Shaw, Chris G.

    2012-07-01

    This Performance Assessment (PA) submittal is an update to the original PA that was developed to support the licensing of the Waste Control Specialists LLC Low-Level Radioactive Waste (LLRW) disposal facility. This update includes both the Compact Waste Facility (CWF) and the Federal Waste Facility (FWF), in accordance with Radioactive Material License (RML) No. R04100, License Condition (LC) 87. While many of the baseline assumptions supporting the initial license application PA were incorporated in this update, a new transport code, GoldSim, and new deterministic groundwater flow codes, including HYDRUS and MODFLOWSURFACT{sup TM}, were employed to demonstrate compliance with the performance objectives codified in the regulations and RML No. R04100, LC 87. A revised source term, provided by the Texas Commission on Environmental Quality staff, was used to match the initial 15 year license term. This updated PA clearly confirms and demonstrates the robustness of the characteristics of the site's geology and the advanced engineering design of the disposal units. Based on the simulations from fate and transport models, the radiation doses to members of the general public and site workers predicted in the initial and updated PA were a small fraction of the criterion doses of 0.25 mSv and 50 mSv, respectively. In a comparison between the results of the updated PA against the one developed in support of the initial license, both clearly demonstrated the robustness of the characteristics of the site's geology and engineering design of the disposal units. Based on the simulations from fate and transport models, the radiation doses to members of the general public predicted in the initial and updated PA were a fraction of the allowable 25 mrem/yr (0.25 m sievert/yr) dose standard for tens-of-thousands of years into the future. Draft Texas guidance on performance assessment (TCEQ, 2004) recommends a period of analysis equal to 1,000 years or until peak doses from the more

  15. RCRA designation of discarded americium/beryllium sealed sources

    SciTech Connect

    Kirner, N.P.

    1994-09-01

    Many sealed sources containing americium and beryllium are used throughout construction, industry, and research, and will eventually require disposal. For planning purposes it is necessary to determine whether these sources, when disposed, constitute a mixed waste, i.e., a waste containing hazardous constituents regulated under the Resource Conservation and Recovery Act and radioactive constituents regulated under the Atomic Energy Act. Waste designation criteria contained in 40 CFR 261 are evaluated in detail in this report. It is determined that discarded americium/beryllium sealed sources do not contain any wastes listed in Subpart D of 40 CFR 261, nor do the discarded sources exhibit any hazardous characteristics. Therefore, it is concluded that discarded americium/beryllium sealed sources are not a mixed waste under regulations established by the US Environmental Protection Agency. Hazardous waste regulatory programs delegated to States, however, may have regulations that differ from those of the Federal government.

  16. Potential GTCC LLW sealed radiation source recycle initiatives

    SciTech Connect

    Fischer, D

    1992-04-01

    This report suggests 11 actions that have the potential to facilitate the recycling (reuse or radionuclide) of surplus commercial sealed radiation sources that would otherwise be disposed of as greater-than-Class C low-level radioactive waste. The suggestions serve as a basis for further investigation and discussion between the Department of Energy, Nuclear Regulatory Commission, Agreement States, and the commercial sector. Information is also given that describes sealed sources, how they are used, and problems associated with recycling, including legal concerns. To illustrate the nationwide recycling potential, Appendix A gives the estimated quantity and application information for sealed sources that would qualify for disposal in commercial facilities if not recycle. The report recommends that the Department of Energy initiate the organization of a forum to explore the suggested actions and other recycling possibilities.

  17. A performance assessment methodology for high-level radioactive waste disposal in unsaturated, fractured tuff

    SciTech Connect

    Gallegos, D.P.

    1991-07-01

    Sandia National Laboratories, has developed a methodology for performance assessment of deep geologic disposal of high-level nuclear waste. The applicability of this performance assessment methodology has been demonstrated for disposal in bedded salt and basalt; it has since been modified for assessment of repositories in unsaturated, fractured tuff. Changes to the methodology are primarily in the form of new or modified ground water flow and radionuclide transport codes. A new computer code, DCM3D, has been developed to model three-dimensional ground-water flow in unsaturated, fractured rock using a dual-continuum approach. The NEFTRAN 2 code has been developed to efficiently model radionuclide transport in time-dependent velocity fields, has the ability to use externally calculated pore velocities and saturations, and includes the effect of saturation dependent retardation factors. In order to use these codes together in performance-assessment-type analyses, code-coupler programs were developed to translate DCM3D output into NEFTRAN 2 input. Other portions of the performance assessment methodology were evaluated as part of modifying the methodology for tuff. The scenario methodology developed under the bedded salt program has been applied to tuff. An investigation of the applicability of uncertainty and sensitivity analysis techniques to non-linear models indicate that Monte Carlo simulation remains the most robust technique for these analyses. No changes have been recommended for the dose and health effects models, nor the biosphere transport models. 52 refs., 1 fig.

  18. Environmental Modeling and Bayesian Analysis for Assessing Human Health Impacts from Radioactive Waste Disposal

    NASA Astrophysics Data System (ADS)

    Stockton, T.; Black, P.; Tauxe, J.; Catlett, K.

    2004-12-01

    Bayesian decision analysis provides a unified framework for coherent decision-making. Two key components of Bayesian decision analysis are probability distributions and utility functions. Calculating posterior distributions and performing decision analysis can be computationally challenging, especially for complex environmental models. In addition, probability distributions and utility functions for environmental models must be specified through expert elicitation, stakeholder consensus, or data collection, all of which have their own set of technical and political challenges. Nevertheless, a grand appeal of the Bayesian approach for environmental decision- making is the explicit treatment of uncertainty, including expert judgment. The impact of expert judgment on the environmental decision process, though integral, goes largely unassessed. Regulations and orders of the Environmental Protection Agency, Department Of Energy, and Nuclear Regulatory Agency orders require assessing the impact on human health of radioactive waste contamination over periods of up to ten thousand years. Towards this end complex environmental simulation models are used to assess "risk" to human and ecological health from migration of radioactive waste. As the computational burden of environmental modeling is continually reduced probabilistic process modeling using Monte Carlo simulation is becoming routinely used to propagate uncertainty from model inputs through model predictions. The utility of a Bayesian approach to environmental decision-making is discussed within the context of a buried radioactive waste example. This example highlights the desirability and difficulties of merging the cost of monitoring, the cost of the decision analysis, the cost and viability of clean up, and the probability of human health impacts within a rigorous decision framework.

  19. Assessment of the effect of a bentonite seal on groundwater storage in underlying waste disposal trenches at Oak Ridge National Laboratory

    SciTech Connect

    Arora, H.S.; Huff, D.D.; Ward, D.S.; Sealand, O.M.

    1981-03-01

    For a 49-trench section that was sealed in Solid Waste Disposal Area 6, the water-table elevation was periodically measured to assess the effectiveness of the seal for controlling the intrustion of water. Water was found in a majority of trenches throughout the study period (May 1978-December 1979). Mean seasonal water-table fluctuations indicated an average rise of 131 +- 56 cm in waste trenches between October 30, 1978 (minimum level) and February 15, 1979 (maximum level). This mean difference corresponds to an estimated gain of 1000 m/sup 3/ of groundwater storage in the trench area. The measured depths to water in the trenches showed a general correspondence with those in monitoring wells (augered during September 1979) outside the trenches in the undisturbed zone in the downslope southern half of the study area. In contrast, the measured depths to water were relatively greater in wells in the undisturbed zone in comparison with those in trenches in the upslope northern half of the study area. This suggests that perched water tables developed within the trenches in the upslope area. The groundwater table (potentiometric surface) contours essentially followed the topographic contours and indicated a predominant gradient toward the south-southwest, which is in the direction of a backfilled topographic draw with a known seep at its base. The reported hydrologic characteristics of the Oak Ridge area, laboratory studies in the development of bentonite application rates, and simulation studies using a hydrologic computer code suggested that a significant part of the groundwater observed in the study area was associated with groundwater intrusion from the surrounding upslope area.

  20. Corrosion behaviour of steel rebars embedded in a concrete designed for the construction of an intermediate-level radioactive waste disposal facility

    NASA Astrophysics Data System (ADS)

    Duffó, G. S.; Arva, E. A.; Schulz, F. M.; Vazquez, D. R.

    2013-07-01

    The National Atomic Energy Commission of the Argentine Republic is developing a nuclear waste disposal management programme that contemplates the design and construction of a facility for the final disposal of intermediate-level radioactive wastes. The repository is based on the use of multiple, independent and redundant barriers. The major components are made in reinforced concrete so, the durability of these structures is an important aspect for the facility integrity. This work presents an investigation performed on an instrumented reinforced concrete prototype specifically designed for this purpose, to study the behaviour of an intermediate level radioactive waste disposal facility from the rebar corrosion point of view. The information obtained will be used for the final design of the facility in order to guarantee a service life more or equal than the foreseen durability for this type of facilities.

  1. Review of potential host rocks for radioactive waste disposal in the Piedmont Province of Georgia

    SciTech Connect

    Wenner, D.B.; Gillon, K.A.

    1980-10-01

    A literature study was conducted on the Piedmont province of Georgia to designate areas that may be favorable for field exploration for consideration of a repository for storage of radioactive waste. The criteria utilized in such a designation was based upon consideration of the rock unit having favorable geological, geotechnical, and geohydrological features. The most important are that the rock unit have: (1) satisfactory unit dimensions (> 100 km/sup 2/ outcrop area and at least 1500 meters (approx. 5000 feet) depth of a continuous rock type); and (2) acceptable geohydrological conditions. Among all rock types, it is concluded that the granites of the large post-metamorphic plutons and large, homogeneous orthogneissic units offer the most favorable geologic settings for exploration for siting a radioactive waste repository. Virtually all other rock types, including most metavolcanic and metasedimentary lithologies have unacceptable unit dimensions, generally unfavorable geohydrologic settings, and deleterious mechanical and physical geotechnical properties. After consideration of all major lithologies that comprise the Georgia Piedmont, the following units were deemed favorable: (1) the Elberton Pluton; (2) the Siloam Pluton; (3) the Sparta Pluton; (4) two unnamed plutons adjacent to the Snelson body of S.W. Georgia; (5) the Lithonia Gneiss; (6) basement orthogneisses and charnockites of the Pine Mountain Belt.

  2. Method for disposing of radioactive graphite and silicon carbide in graphite fuel elements

    SciTech Connect

    Gay, R.L.

    1995-09-12

    Method is described for destroying radioactive graphite and silicon carbide in fuel elements containing small spheres of uranium oxide coated with silicon carbide in a graphite matrix, by treating the graphite fuel elements in a molten salt bath in the presence of air, the salt bath comprising molten sodium-based salts such as sodium carbonate and a small amount of sodium sulfate as catalyst, or calcium-based salts such as calcium chloride and a small amount of calcium sulfate as catalyst, while maintaining the salt bath in a temperature range of about 950 to about 1,100 C. As a further feature of the invention, large radioactive graphite fuel elements, e.g. of the above composition, can be processed to oxidize the graphite and silicon carbide, by introducing the fuel element into a reaction vessel having downwardly and inwardly sloping sides, the fuel element being of a size such that it is supported in the vessel at a point above the molten salt bath therein. Air is bubbled through the bath, causing it to expand and wash the bottom of the fuel element to cause reaction and destruction of the fuel element as it gradually disintegrates and falls into the molten bath. 4 figs.

  3. Applications of UThPb isotope systematics to the problems of radioactive waste disposal

    USGS Publications Warehouse

    Stuckless, J.S.

    1986-01-01

    mobility can be obtained through the use of isotopic studies. Such information can be extremely important in the search for favorable hosts for containment of radioactive waste. Rocks such as the Go??temar Granite have undergone considerable rock-water interaction, most of which occurred ??? 400 Myr. ago and little in recent times. Thus a search for zones that have experienced only a little interaction with water may provide a misleading prediction as to the ability of such zones to shield radioactive wastes from the modern biosphere. From an isotopic point of view, an ideal candidate for evaluation as a host rock for radioactive wastes would have the following characteristics: (1) a high ratio (> 2) of radiogenic to common Pb in order to optimize precision of the results; (2) a simple two-stage geologic history so that results could be interpreted without multiple working hypotheses; and (3) an originally high percentage (> 50%) of labile U so that the results would be highly sensitive to even small amount of rock-water interaction. These characteristics should produce rocks with marked radioactive disequilibrium in surface samples. The disequilibrium should grade to radioactive equilibrium with increasing depth until zones in which water has not circulated are found. Extensive regions of such zones must exist because UThPb systematics of most analyzed granitoids demonstrate closed-system behavior for almost all of their history except for their recent history in the near-surface environment. ?? 1986.

  4. Core disruptive accident margin seal

    DOEpatents

    Golden, Martin P.

    1979-01-01

    Apparatus for sealing the annulus defined within a substantially cylindrical rotatable riser assembly and plug combination of a nuclear reactor closure head. The apparatus comprises an inflatable sealing mechanism disposed in one portion of the riser assembly near the annulus such that upon inflation the sealing mechanism is radially actuated against the other portion of the riser assembly thereby sealing the annulus. The apparatus further comprises a connecting mechanism which places one end of the sealing mechanism in fluid communication with the reactor cover gas so that overpressurization of the reactor cover gas will increase the radial actuation of the sealing mechanism thus enhancing sealing of the annulus.

  5. Container Approval for the Disposal of Radioactive Waste with Negligible Heat Generation in the German Konrad Repository - 12148

    SciTech Connect

    Voelzke, Holger; Nieslony, Gregor; Ellouz, Manel; Noack, Volker; Hagenow, Peter; Kovacs, Oliver; Hoerning, Tony

    2012-07-01

    Since the license for the Konrad repository was finally confirmed by legal decision in 2007, the Federal Institute for Radiation Protection (BfS) has been performing further planning and preparation work to prepare the repository for operation. Waste conditioning and packaging has been continued by different waste producers as the nuclear industry and federal research institutes on the basis of the official disposal requirements. The necessary prerequisites for this are approved containers as well as certified waste conditioning and packaging procedures. The Federal Institute for Materials Research and Testing (BAM) is responsible for container design testing and evaluation of quality assurance measures on behalf of BfS under consideration of the Konrad disposal requirements. Besides assessing the container handling stability (stacking tests, handling loads), design testing procedures are performed that include fire tests (800 deg. C, 1 hour) and drop tests from different heights and drop orientations. This paper presents the current state of BAM design testing experiences about relevant container types (box shaped, cylindrical) made of steel sheets, ductile cast iron or concrete. It explains usual testing and evaluation methods which range from experimental testing to analytical and numerical calculations. Another focus has been laid on already existing containers and packages. The question arises as to how they can be evaluated properly especially with respect to lack of completeness of safety assessment and fabrication documentation. At present BAM works on numerous applications for container design testing for the Konrad repository. Some licensing procedures were successfully finished in the past and BfS certified several container types like steel sheet, concrete until cast iron containers which are now available for waste packaging for final disposal. However, large quantities of radioactive wastes had been placed into interim storage using containers which

  6. Tale taming radioactive fears: Linking nuclear waste disposal to the "continuum of the good".

    PubMed

    Yli-Kauhaluoma, Sari; Hänninen, Hannu

    2014-04-01

    We examine how the constructor of the world's first repository for the final disposal of spent nuclear fuel in Eurajoki, Finland, aims to shape lay understanding of the facility's risks and to tame the nuclear fears of the local community by producing positive associations, imagery and tales. Our empirical material consists of the constructor's newsletters targeted mainly at the local residents. In the narrative analysis, we identified a storyline where the construction of the repository is linked into the "continuum of the good" in the municipality of the construction site and the surrounding areas. The storyline consists of five different themes all emphasizing the "continuum of the good" in the area: cultural heritage, well-being, developing expertise, natural environment, and local families. Our study contributes to the literature on pro-nuclear storytelling by showing how the inclination is towards narratives that are constructed around local symbols, cultural landmarks, and institutions. PMID:24113741

  7. Mixed-layered bismuth-oxygen-iodine materials for capture and waste disposal of radioactive iodine

    DOEpatents

    Krumhansl, James L; Nenoff, Tina M

    2013-02-26

    Materials and methods of synthesizing mixed-layered bismuth oxy-iodine materials, which can be synthesized in the presence of aqueous radioactive iodine species found in caustic solutions (e.g. NaOH or KOH). This technology provides a one-step process for both iodine sequestration and storage from nuclear fuel cycles. It results in materials that will be durable for repository conditions much like those found in Waste Isolation Pilot Plant (WIPP) and estimated for Yucca Mountain (YMP). By controlled reactant concentrations, optimized compositions of these mixed-layered bismuth oxy-iodine inorganic materials are produced that have both a high iodine weight percentage and a low solubility in groundwater environments.

  8. Mixed-layered bismuth--oxygen--iodine materials for capture and waste disposal of radioactive iodine

    DOEpatents

    Krumhansl, James L; Nenoff, Tina M

    2015-01-06

    Materials and methods of synthesizing mixed-layered bismuth oxy-iodine materials, which can be synthesized in the presence of aqueous radioactive iodine species found in caustic solutions (e.g. NaOH or KOH). This technology provides a one-step process for both iodine sequestration and storage from nuclear fuel cycles. It results in materials that will be durable for repository conditions much like those found in Waste Isolation Pilot Plant (WIPP) and estimated for Yucca Mountain (YMP). By controlled reactant concentrations, optimized compositions of these mixed-layered bismuth oxy-iodine inorganic materials are produced that have both a high iodine weight percentage and a low solubility in groundwater environments.

  9. Treatment of Radioactive Metallic Waste from Operation of Nuclear Power Plants by Melting - The German Way for a Consistent Recycling to Minimize the Quantity of Radioactive Waste from Operation and Dismantling for Disposal - 12016

    SciTech Connect

    Wegener, Dirk; Kluth, Thomas

    2012-07-01

    During maintenance of nuclear power plants, and during their decommissioning period, a large quantity of radioactive metallic waste will accrue. On the other hand the capacity for final disposal of radioactive waste in Germany is limited as well as that in the US. That is why all procedures related to this topic should be handled with a maximum of efficiency. The German model of consistent recycling of the radioactive metal scrap within the nuclear industry therefore also offers high capabilities for facilities in the US. The paper gives a compact overview of the impressive results of melting treatment, the current potential and further developments. Thousands of cubic metres of final disposal capacity have been saved. The highest level of efficiency and safety by combining general surface decontamination by blasting and nuclide specific decontamination by melting associated with the typical effects of homogenization. An established process - nationally and internationally recognized. Excellent connection between economy and ecology. (authors)

  10. Disposal rabbit

    DOEpatents

    Lewis, L.C.; Trammell, D.R.

    1983-10-12

    A disposable rabbit for transferring radioactive samples in a pneumatic transfer system comprises aerated plastic shaped in such a manner as to hold a radioactive sample and aerated such that dissolution of the rabbit in a solvent followed by evaporation of the solid yields solid waste material having a volume significantly smaller than the original volume of the rabbit.

  11. Disposable rabbit

    DOEpatents

    Lewis, Leroy C.; Trammell, David R.

    1986-01-01

    A disposable rabbit for transferring radioactive samples in a pneumatic transfer system comprises aerated plastic shaped in such a manner as to hold a radioactive sample and aerated such that dissolution of the rabbit in a solvent followed by evaporation of the solid yields solid waste material having a volume significantly smaller than the original volume of the rabbit.

  12. Problems in shallow land disposal of solid low-level radioactive waste in the united states

    USGS Publications Warehouse

    Stevens, P.R.; DeBuchananne, G.D.

    1976-01-01

    Disposal of solid low-level wastes containing radionuclides by burial in shallow trenches was initiated during World War II at several sites as a method of protecting personnel from radiation and isolating the radionuclides from the hydrosphere and biosphere. Today, there are 11 principal shallow-land burial sites in the United States that contain a total of more than 1.4 million cubic meters of solid wastes contaminated with a wide variety of radionuclides. Criteria for burial sites have been few and generalized and have contained only minimal hydrogeologic considerations. Waste-management practices have included the burial of small quantities of long-lived radionuclides with large volumes of wastes contaminated with shorter-lived nuclides at the same site, thereby requiring an assurance of extremely long-time containment for the entire disposal site. Studies at 4 of the 11 sites have documented the migration of radionuclides. Other sites are being studied for evidence of containment failure. Conditions at the 4 sites are summarized. In each documented instance of containment failure, ground water has probably been the medium of transport. Migrating radionuclides that have been identified include90Sr,137Cs,106Ru,239Pu,125Sb,60Co, and3H. Shallow land burial of solid wastes containing radionuclides can be a viable practice only if a specific site satisfies adequate hydrogeologic criteria. Suggested hydrogeologic criteria and the types of hydrogeologic data necessary for an adequate evaluation of proposed burial sites are given. It is mandatory that a concomitant inventory and classification be made of the longevity, and the physical and chemical form of the waste nuclides to be buried, in order that the anticipated waste types can be matched to the containment capability of the proposed sites. Ongoing field investigations at existing sites will provide data needed to improve containment at these sites and help develop hydrogeologic criteria for new sites. These

  13. Radioactive and nonradioactive waste intended for disposal at the Waste Isolation Pilot Plant

    SciTech Connect

    SANCHEZ,LAWRENCE C.; DREZ,P.E.; RATH,JONATHAN S.; TRELLUE,H.R.

    2000-05-19

    Transuranic (TRU) waste generated by the handling of plutonium in research on or production of US nuclear weapons will be disposed of in the Waste Isolation Pilot Plant (WIPP). This paper describes the physical and radiological properties of the TRU waste that will be deposited in the WIPP. This geologic repository will accommodate up to 175,564 m{sup 3} of TRU waste, corresponding to 168,485 m{sup 3} of contact-handled (CH-) TRU waste and 7,079 m{sup 3} of remote-handled (RH-) TRU waste. Approximately 35% of the TRU waste is currently packaged and stored (i.e., legacy) waste, with the remainder of the waste to be packaged or generated and packaged in activities before the year 2033, the closure time for the repository. These wastes were produced at 27 US Department of Energy (DOE) sites in the course of generating defense nuclear materials. The radionuclide and nonradionuclide inventories for the TRU wastes described in this paper were used in the 1996 WIPP Compliance Certification Application (CCA) performance assessment calculations by Sandia National Laboratories/New Mexico (SNL/NM).

  14. Research and Development of a New Silica-Alumina Based Cementitious Material Largely Using Coal Refuse for Mine Backfill, Mine Sealing and Waste Disposal Stabilization

    SciTech Connect

    Henghu Sun; Yuan Yao

    2012-06-29

    Coal refuse and coal combustion byproducts as industrial solid waste stockpiles have become great threats to the environment. To activate coal refuse is one practical solution to recycle this huge amount of solid waste as substitute for Ordinary Portland Cement (OPC). The central goal of this project is to investigate and develop a new silica-alumina based cementitious material largely using coal refuse as a constituent that will be ideal for durable construction, mine backfill, mine sealing and waste disposal stabilization applications. This new material is an environment-friendly alternative to Ordinary Portland Cement. The main constituents of the new material are coal refuse and other coal wastes including coal sludge and coal combustion products (CCPs). Compared with conventional cement production, successful development of this new technology could potentially save energy and reduce greenhouse gas emissions, recycle vast amount of coal wastes, and significantly reduce production cost. A systematic research has been conducted to seek for an optimal solution for enhancing pozzolanic reactivity of the relatively inert solid waste-coal refuse in order to improve the utilization efficiency and economic benefit as a construction and building material.

  15. Iraq nuclear facility dismantlement and disposal project

    SciTech Connect

    Cochran, J.R.; Danneels, J.; Kenagy, W.D.; Phillips, C.J.; Chesser, R.K.

    2007-07-01

    The Al Tuwaitha nuclear complex near Baghdad contains a significant number of nuclear facilities from Saddam Hussein's dictatorship. Because of past military operations, lack of upkeep and looting there is now an enormous radioactive waste problem at Al Tuwaitha. Al Tuwaitha contains uncharacterised radioactive wastes, yellow cake, sealed radioactive sources, and contaminated metals. The current security situation in Iraq hampers all aspects of radioactive waste management. Further, Iraq has never had a radioactive waste disposal facility, which means that ever increasing quantities of radioactive waste and material must be held in guarded storage. The Iraq Nuclear Facility Dismantlement and Disposal Program (the NDs Program) has been initiated by the U.S. Department of State (DOS) to assist the Government of Iraq (GOI) in eliminating the threats from poorly controlled radioactive materials, while building human capacities so that the GOI can manage other environmental cleanups in their country. The DOS has funded the International Atomic Energy Agency (IAEA) to provide technical assistance to the GOI via a Technical Cooperation Project. Program coordination will be provided by the DOS, consistent with U.S. and GOI policies, and Sandia National Laboratories will be responsible for coordination of participants and for providing waste management support. Texas Tech University will continue to provide in-country assistance, including radioactive waste characterization and the stand-up of the Iraq Nuclear Services Company. The GOI owns the problems in Iraq and will be responsible for the vast majority of the implementation of the NDs Program. (authors)

  16. Aft outer rim seal arrangement

    DOEpatents

    Lee, Ching-Pang; Tham, Kok-Mun; Schroeder, Eric; Meeroff, Jamie; Miller, Jr., Samuel R; Marra, John J; Campbell, Christian X

    2015-04-28

    An outer rim seal arrangement (10), including: an annular rim (70) centered about a longitudinal axis (30) of a rotor disc (31), extending fore and having a fore-end (72), an outward-facing surface (74), and an inward-facing surface (76); a lower angel wing (62) extending aft from a base of a turbine blade (22) and having an aft end (64) disposed radially inward of the rim inward-facing surface to define a lower angel wing seal gap (80); an upper angel wing (66) extending aft from the turbine blade base and having an aft end (68) disposed radially outward of the rim outward-facing surface to define a upper angel wing seal gap (80, 82); and guide vanes (100) disposed on the rim inward-facing surface in the lower angel wing seal gap. Pumping fins (102) may be disposed on the upper angel wing seal aft end in the upper angel wing seal gap.

  17. Geochemical information for the West Chestnut Ridge Central Waste Disposal Facility for low-level radioactive waste

    SciTech Connect

    Seeley, F.G.; Kelmers, A.D.

    1984-06-01

    Geochemical support activities for the Central Waste Disposal Facility (CWDF) project included characterization of site materials, as well as measurement of radionuclide sorption and desorption isotherms and apparent concentration limit values under site-relevant laboratory test conditions. The radionuclide sorption and solubility information is needed as input data for the pathways analysis calculations to model expected radioactivity releases from emplaced waste to the accessible environment under various release scenarios. Batch contact methodology was used to construct sorption and desorption isotherms for a number of radionuclides likely to be present in waste to be disposed of at the site. The sorption rates for uranium and europium were rapid (> 99.8% of the total radionuclide present was adsorbed in approx. 30 min). With a constant-pH isotherm technique, uranium, strontium, cesium, and curium exhibited maximum Rs values of 4800 to > 30,000 L/kg throughout the pH range 5 to 7. Sorption ratios were generally lower at higher or lower pH levels. Retardation factors for uranium, strontium, and cesium, explored by column chromatographic tests, were consistent with the high sorption ratios measured in batch tests for these radionuclides. The addition of as little as 0.01 M organic reagent capable of forming strong soluble complexes with metals (e.g., ethylenediaminetetraacetic acid (EDTA) or citric acid) was found to reduce the sorption ratio for uranium by as much as two orders of magnitude. Substitution of an actual low-level waste site trench water for groundwater in these tests was found to give a similar reduction in the sorption ratio.

  18. SimER: An advanced three-dimensional environmental risk assessment code for contaminated land and radioactive waste disposal applications

    SciTech Connect

    Kwong, S.; Small, J.; Tahar, B.

    2007-07-01

    SimER (Simulations of Environmental Risks) is a powerful performance assessment code developed to undertake assessments of both contaminated land and radioactive waste disposal. The code can undertake both deterministic and probabilistic calculations, and is fully compatible with all available best practice guidance and regulatory requirements. SimER represents the first time-dependent performance assessment code capable of providing a detailed representation of system evolution that is designed specifically to address issues found across UK nuclear sites. The code adopts flexible input language with build-in unit checking to model the whole system (i.e. near-field, geosphere and biosphere) in a single code thus avoiding the need for any time consuming data transfer and the often laborious interface between the different codes. This greatly speeds up the assessment process and has major quality assurance advantages. SimER thus provides a cost-effective tool for undertaking projects involving risk assessment from contaminated land assessments through to full post-closure safety cases and other work supporting key site endpoint decisions. A Windows version (v1.0) of the code was first released in June 2004. The code has subsequently been subject to further testing and development. In particular, Viewers have been developed to provide users with visual information to assist the development of SimER models, and output can now be produced in a format that can be used by the FieldView software to view the results and produce animation from the SimER calculations. More recently a Linux version of the code has been produced to extend coverage to the commonly used platform bases and offer an improved operating environment for probabilistic assessments. Results from the verification of the SimER code for a sample of test cases for both contaminated land and waste disposal applications are presented. (authors)

  19. Review of potential host rocks for radioactive waste disposal in the southeastern United States. Executive summary

    SciTech Connect

    Bledsoe, H.W. Jr.; Marine, I.W.

    1980-10-01

    The geology of the southeastern United States was studied to recommend areas that should be considered for field exploration in order to select a site for a radioactive waste repository. The region studied included the Piedmont Province, the Triassic Basins, and the Atlantic Coastal Plain in Maryland, Virginia, North Carolina, South Carolina, and Georgia. This study was entirely a review of literature and existing knowledge from a geotechnical point of view and was performed by subcontractors whose individual reports are listed in the bibliography. No field work was involved. The entire study was geotechnical in nature, and no consideration was given to socioeconomic or demographic factors. These factors need to be addressed in a separate study. For all areas, field study is needed before any area is further considered. A total of 29 areas are recommended for further consideration in the Piedmont Province subregion: one area in Maryland, 8 areas in Virginia, 4 areas in North Carolina, 6 areas in South Carolina, and 10 areas in Georgia. Of the 14 exposed and 5 buried or hypothesized basins identified in the Triassic basin subregion, 6 are recommended for further study: one basin in Virginia, 3 basins in North Carolina, and 2 basins in South Carolina. Four potential candidate areas are identified within the Atlantic Coastal Plain subregion: one in Maryland, one in North Carolina, and 2 in Georgia.

  20. Performance Impact of Fast Flow Paths Through Grout Monoliths Used for Radioactive Waste Disposal - 13224

    SciTech Connect

    Dinwiddie, Cynthia L.; Walter, Gary R.; Esh, David W.; Barr, Cynthia S.

    2013-07-01

    Empty HLW handling and storage tanks at SRS and INL contain residual radioactivity; these tanks are being stabilized with cementitious grout during closure operations. The US NRC directed the Center for Nuclear Waste Regulatory Analyses (CNWRA{sup R}) to develop physical analogs of cementitious grout monoliths to investigate their potential to form fast flow pathways such as macro-cracks, separations between grout lifts, and annuli around pipes, supports, and along tank walls. CNWRA developed and tested 15 55-gal-drum-scale specimens and 2 larger specimens of tank-filling cementitious grout, and 9 specimens of pipe-filling grout. These experiments demonstrated that the size of fast flow pathways that develop and the peak temperatures attained during hydration are proportional to the scale of the specimen, and that annular apertures and bulk grout permeability generally increased with time post-placement. Cracks developed overnight following placement of each grout lift in the largest specimen, but developed more slowly in smaller specimens, perhaps due to a ∼20 deg. C difference in peak temperatures, which influence the thermal gradients that can induce cracking. Plastic and drying shrinkage commonly led to poor grout-to-metal and grout-to-grout bonding. Cracks, annular gaps, and grout flow lobe seams transmitted fluids during injection testing. Macro-scale flow pathways such as these are not readily observed in bench-scale specimens of cementitious tank grout. (authors)

  1. Hydrogeology of a low-level radioactive-waste disposal site near Sheffield, Illinois

    USGS Publications Warehouse

    Foster, J.B.; Erickson, J.R.; Healy, R.W.

    1984-01-01

    The Sheffield low-level radioactive-waste facility is located on 20 acres of rolling terrain 3 miles southwest of Sheffield, Illinois. The shallow hydrogeologic system is composed of glacial sediments. Pennsylvania shale and mudstone bedrock isolate the regional aquifers below from the hydrogeologic system in the overlying glacial deposits. Pebbly sand underlies 67 percent of the site. Two ground-water flow paths were identified. The primary path conveys ground water from the site to the east through the pebbly-sand unit; a secondary path conveys ground water to the south and east through less permeable material. The pebbly-sand unit provides an underdrain that eliminates the risk of water rising into the trenches. Digital computer model results indicate that the pebbly-sand unit controls ground-water movement. Tritium found migrating in ground water in the southeast corner of the site travels approximately 25 feet per year. A group of water samples from wells which contained the highest tritium concentrations had specific conductivities, alkalinities, hardness, and chloride, sulfate, calcium, and magnesium contents higher than normal for local shallow ground water. (USGS)

  2. SIMULATION OF FLUID FLOW AND ENERGY TRANSPORT PROCESSES ASSOCIATED WITH HIGH-LEVEL RADIOACTIVE WASTE DISPOSAL IN UNSATURATED ALLUVIUM.

    USGS Publications Warehouse

    Pollock, David W.

    1986-01-01

    Many parts of the Great Basin have thick zones of unsaturated alluvium which might be suitable for disposing of high-level radioactive wastes. A mathematical model accounting for the coupled transport of energy, water (vapor and liquid), and dry air was used to analyze one-dimensional, vertical transport above and below an areally extensive repository. Numerical simulations were conducted for a hypothetical repository containing spent nuclear fuel and located 100 m below land surface. Initial steady state downward water fluxes of zero (hydrostatic) and 0. 0003 m yr** minus **1 were considered in an attempt to bracket the likely range in natural water flux. Predicted temperatures within the repository peaked after approximately 50 years and declined slowly thereafter in response to the decreasing intensity of the radioactive heat source. The extent of the dry zone was strongly controlled by the mobility of liquid water near the repository under natural conditions. In the case of initial hydrostatic conditions, the dry zone extended approximately 10 m above and 15 m below the repository. For the case of a natural flux of 0. 0003 m yr** minus **1 the relative permeability of water near the repository was initially more than 30 times the value under hydrostatic conditions, consequently the dry zone extended only about 2 m above and 5 m below the repository. In both cases a significant perturbation in liquid saturation levels persisted for several hundred years. This analysis illustrates the extreme sensitivity of model predictions to initial conditions and parameters, such as relative permeability and moisture characteristic curves.

  3. Plutonium Equivalent Inventory for Belowground Radioactive Waste at the Los Alamos National Laboratory Technical Area 54, Area G Disposal Facility - Fiscal Year 2011

    SciTech Connect

    French, Sean B.; Shuman, Rob

    2012-04-18

    The Los Alamos National Laboratory (LANL) generates radioactive waste as a result of various activities. Many aspects of the management of this waste are conducted at Technical Area 54 (TA-54); Area G plays a key role in these management activities as the Laboratory's only disposal facility for low-level radioactive waste (LLW). Furthermore, Area G serves as a staging area for transuranic (TRU) waste that will be shipped to the Waste Isolation Pilot Plant for disposal. A portion of this TRU waste is retrievably stored in pits, trenches, and shafts. The radioactive waste disposed of or stored at Area G poses potential short- and long-term risks to workers at the disposal facility and to members of the public. These risks are directly proportional to the radionuclide inventories in the waste. The Area G performance assessment and composite analysis (LANL, 2008a) project long-term risks to members of the public; short-term risks to workers and members of the public, such as those posed by accidents, are addressed by the Area G Documented Safety Analysis (LANL, 2011a). The Documented Safety Analysis uses an inventory expressed in terms of plutonium-equivalent curies, referred to as the PE-Ci inventory, to estimate these risks. The Technical Safety Requirements for Technical Area 54, Area G (LANL, 2011b) establishes a belowground radioactive material limit that ensures the cumulative projected inventory authorized for the Area G site is not exceeded. The total belowground radioactive waste inventory limit established for Area G is 110,000 PE-Ci. The PE-Ci inventory is updated annually; this report presents the inventory prepared for 2011. The approach used to estimate the inventory is described in Section 2. The results of the analysis are presented in Section 3.

  4. Review and evaluation of principles used in the estimation of radiation doses associated with the practice of deepsea disposal of low-level radioactive waste

    SciTech Connect

    Baker, D.A.; Templeton, W.L.; Soldat, J.K.

    1985-09-01

    The relevant national and international guidance concerning the estimation of radiological doses from the practice of deepsea disposal of radioactive waste was reviewed. The review includes the dose limitation guidance of the various national and international bodies, especially that of the International Commission on Radiological Protection (ICRP). Pathway modeling is discussed as well as the oceanographic models of the International Atomic Energy Agency (IAEA). Included in the discussion are the recommendations for the definition of high-level waste by the IAEA for use by the London Dumping Convention (LDC) in setting limits for ocean disposal of waste. An assessment of the ICRP's radiological protection system using the effective whole-body dose methodology is made. Present models, which should continue to be improved as the research data becomes available, do provide an adequate basis for regulatory authorities to decide whether authorization for a proposed disposal can be granted, since they provide a means of indicating whether maximum individual (critical groups) exposure limits are likely to be exceeded. However, new models and information are continuously being developed by the international community to assess ocean disposal of radioactive waste in comparison to land disposal and to compare one site against another. 47 refs., 2 figs., 4 tabs.

  5. The Site Investigation Of Low-Level Radioactive Waste For Sub-Surface Disposal Facility In Japan

    NASA Astrophysics Data System (ADS)

    Hosoya, S.; Sasaki, T.

    2006-12-01

    [1.Concept of the sub-surface disposal facility] In Japan, the facilities of Low-Level Radioactive West (LLW) for near-surface disposal have already been in operation. Japan Nuclear Fuel Limited (JNFL) has a plan of a new facility of LLW for sub-surface disposal with engineered barrier, for short "the sub-surface disposal facility".This facility can accept the relatively higher low-level waste from unclear power plant operation and in core materials from the decommissioning, estimated about 20 thousands cubic meter in total.In addition, this will accept transuranim (TRU) slightly contaminated waste from reprocessing plant operation and decommissioning. It shall be located at a sufficient depth enough to avoid normal human activities in future. [2.Site investigation] From 2001 to 2006,the site investigation on geology and hydrogeology has been performed in order to acquire the basic data for the design and the safety assessment for the sub-surface disposal facility.The candidate area is located at the site of JNFL, where Rokkasho-mura, Aomori Prefecture in the northern area of the Mainland of Japan.To confirm geology hydraulic conditions and geo-chemistry, 22 boring survey including 6 holes in swamp and marsh have been performed. The 1km long access tunnel (the entrance level EL 8.0m, incline of 1/10) to the altitude of EL -86m underground, around 100m depth from surface, has excavated. During excavating the tunnel, observation of geology, permeability tests, pore water pressure measurements and so on has been performed in situ.And the large size test cavern of 18m diameters was constructed at the end of the tunnel to demonstrate stability of the tunnel. Prior to the excavation, 3 measuring tunnels were excavated surrounding the test cavern to examine the excavation. [3.Geological features] The sedimentary rock called Takahoko formation at the Neogene period is distributed upper than EL-500m in the candidate area.The quaternary stratum about 10m in thickness is

  6. Survey of degradation modes of candidate materials for high-level radioactive-waste disposal containers

    SciTech Connect

    Farmer, J.C.; Van Konynenburg, R.A.; McCright, R.D. ); Bullen, D.B. )

    1988-04-01

    Three iron- to nickel-based austenitic alloys (Types 304L and 316L stainless steels and Alloy 825) are being considered as candidate materials for the fabrication of high-level radioactive-waste containers. Waste will include fuel assemblies from reactors as well as high-level waste in borosilicate glass forms, and will be sent to the prospective repository at Yucca Mountain, Nevada. The decay of radionuclides in the repository will result in the generation of substantial heat and in fluences of gamma radiation. Container materials may undergo any of several modes of degradation in this environment, including atmospheric oxidation; uniform aqueous phase corrosion; pitting; crevice corrosion; sensitization and intergranular stress corrosion cracking (IGSCC); and transgranular stress corrosion cracking (TGSCC). This report is an analysis of data relevant to the pitting, crevice corrosion, and stress corrosion cracking (SCC) of the three austenitic candidate alloys. The candidates are compared in terms of their susceptibilities to these forms of corrosion. Although all three candidates have demonstrated pitting and crevice corrosion in chloride-containing environments, Alloy 825 has the greatest resistance to these types of localized corrosion (LC); such resistance is important because pits can penetrate the metal and serve as crack initiation sites. Both Types 304L and 316L stainless steels are susceptible to SCC in acidic chloride media. In contrast, SCC has not been documented in Alloy 825 under comparable conditions. Gamma radiation has been found to enhance SCC in Types 304 and 304L stainless steels, but it has no detectable effect on the resistance of Alloy 825 to SCC. Furthermore, while the effects of microbiologically induced corrosion have been observed for 300-series stainless steels, nickel-based alloys such as Alloy 825 seem to be immune to such problems. 211 refs., 49 figs., 10 tabs.

  7. Geology of the Powder River Basin, Wyoming and Montana, with reference to subsurface disposal of radioactive wastes

    USGS Publications Warehouse

    Beikman, Helen M.

    1962-01-01

    The Powder River Basin is a structural and topographic basin occupying an area of about 20,000 square miles in northeastern Wyoming arid southeastern Montana. The Basin is about 230 miles long in a northwest-southeast direction and is about 100 miles wide. It is bounded on three sides by mountains in which rocks of Precambrian age are exposed. The Basin is asymmetrical with a steep west limb adjacent to the Bighorn Mountains and a gentle east limb adjacent to the Black Hills. Sedimentary rocks within the Basin have a maximum thickness of about 18,000 feet and rocks of every geologic period are represented. Paleozoic rocks are about 2,500 feet thick and consist of marine bonate rocks and sandstone; Mesozoic rocks are about 9,500 feet thick and consist of both marine and nonmarine siltstone and sandstone; and Cenozoic rocks are from 4,000 to 6,000 feet thick and consist of coal-bearing sandstone and shale. Radioactive waste could be stored in the pore space of permeable sandstone or in shale where space could be developed. Many such rock units that could be used for storing radioactive wastes are present within the Powder River Basin. Permeable sandstone beds that may be possible reservoirs for storage of radioactive waste are present throughout the Powder River Basin. These include sandstone beds in the Flathead Sandstone and equivalent strata in the Deadwood Formation, the Tensleep Sandstone and equivalent strata in the Minnelusa Formation and the Sundance Formation in rocks of pre-Cretaceous age. However, most of the possible sandstone reservoirs are in rocks of Cretaceous age and include sandstone beds in the Fall River, Lakota, Newcastle, Frontier, Cody, and Mesaverde Formations. Problems of containment of waste such as clogging of pore space and chemical incompatibility would have to be solved before a particular sandstone unit could be selected for waste disposal. Several thick sequences of impermeable shale such as those in the Skull Creek, Mowry, Frontier

  8. Trench water chemistry at commercially operated low-level radioactive waste disposal sites. [Trench waters from Maxey Flats, Kentucky and West Valley, New York

    SciTech Connect

    Pietrzak, R.F.; Dayal, R.; Kinsley, M.T.; Clinton, J.; Czyscinski, K.S.; Weiss, A.J.

    1982-01-01

    Water samples from the disposal trenches of two low-level radioactive-waste-disposal sites were analyzed for their inorganic, organic, and radionuclide contents. Since oxidation of the trench waters can occur during their movement along the groundwater flow path, experiments were performed to measure the chemical and physical changes that occur in these waters upon oxidation. Low concentrations of chelating agents, shown to exist in trench waters, may be responsible for keeping radionuclides, particularly /sup 60/Co, in solution. 4 figures, 5 tables.

  9. Radionuclide Concentrations in Soils and Vegetation at Low-Level Radioactive Waste Disposal Area G during the 1997 Growing Season

    SciTech Connect

    L. Naranjo, Jr.; P. R. Fresquez; R. J. Wechsler

    1998-08-01

    Soil and overstory and understory vegetation (washed and unwashed) collected at eight locations within and around Area G-a low-level radioactive solid-waste disposal facility at Los Alamos National Laboratory-were analyzed for 3H, 238Pu, 239Pu, 137CS, 234U, 235U, 228AC, Be, 214Bi, 60Co, 40& 54Mn, 22Na, 214Pb and 208Tl. In general, most radionuclide concentrations, with the exception of 3Ef and ~9Pu, in soils and overstory and understory vegetation collected from within and around Area G were within upper (95'%) level background concentrations. Although 3H concentrations in vegetation from most sites were significantly higher than background (>2 pCi mL-l), concentrations decreased markedly in comparison to last year's results. The highest `H concentration in vegetation was detected from a juniper tree that was growing over tritium shaft /+150; it contained 530,000 pCi 3H mL-l. Also, as in the pas~ the transuranic waste pad area contained the highest levels of 239Pu in soils and in understory vegetation as compared to other areas at Area G.

  10. Radionuclide concentrations in soils and vegetation at radioactive-waste disposal Area G during the 1996 growing season. Progress report

    SciTech Connect

    Fresquez, P.R.; Vold, E.L.; Naranjo, L. Jr.

    1997-07-01

    Soil and overstory and understory vegetation (washed and unwashed) collected at eight locations within and around Area G--a low-level radioactive solid-waste disposal facility at Los Alamos National laboratory--were analyzed for {sup 3}H, {sup 90}Sr, {sup 238}Pu, {sup 239}Pu, {sup 137}Cs, {sup 234}U, {sup 235}U, {sup 238}U, {sup tot}U, {sup 228}Ac, {sup 214}Bi, {sup 60}Co, {sup 40}K, {sup 54}Mn, {sup 22}Na, {sup 214}Pb, and {sup 208}Tl. Also, heavy metals (Ag, As, Ba, Be, Cd, Cr, Hg, Ni, Pb, Sb, Se, and Tl) in soil and vegetation were determined. In general, most radionuclide concentrations, with the exception of {sup 3}H and {sup 239}Pu, in soils and washed and unwashed overstory and understory vegetation collected from within and around Area G were within upper limit background concentrations. Tritium was detected as high as 14,744 pCi mL{sup {minus}1} in understory vegetation collected from transuranic (TRU) waste pad {number_sign}4, and the TRU waste pad area contained the highest levels of {sup 239}Pu in soils and in understory vegetation as compared to other areas at Area G.

  11. Calculation of absorbed dose around a facility for disposing of low activity natural radioactive waste (C3-dump).

    PubMed

    Jansen, J T M; Zoetelief, J

    2005-01-01

    A C3-dump is a facility for disposing of low activity natural radioactive waste containing the uranium series 238U, the thorium series 232Th and 40K. Only the external radiation owing to gamma rays, X-rays and annihilation photons is considered in this study. For two situations--the semi-infinite slab and the tourist geometry--the conversion coefficients from specific activity to air kerma rate at 1 m above the relevant level are calculated. In the first situation the waste material is in contact with the air but in the tourist geometry it is covered with a 1.35 m thick layer. For the calculations, the Monte Carlo radiation transport code MCNP is used. The yield and photon energy for each radionuclide are according to the database of Oak Ridge National Laboratory. For the tourist situation, the depth-dose distribution through the covering layer is calculated and extrapolated to determine the exit dose. PMID:16604673

  12. Preliminary hydrogeologic evaluation of the Cincinnati Arch region for underground high-level radioactive waste disposal, Indiana, Kentucky , and Ohio

    USGS Publications Warehouse

    Lloyd, O.B.; Davis, R.W.

    1989-01-01

    Preliminary interpretation of available hydrogeologic data suggests that some areas underlying eastern Indiana, north-central Kentucky, and western Ohio might be worthy of further study regarding the disposal of high-level radioactive waste in Precambrian crystalline rocks buried beneath Paleozoic sedimentary rocks in the area. The data indicate that (1) largest areas of deepest potential burial and thickest sedimentary rock cover occur in eastern Indiana; (2) highest concentrations of dissolved solids in the basal sandstone aquifer, suggesting the most restricted circulation, are found in the southern part of the area near the Kentucky-Ohio State line and in southeastern Indiana; (3) largest areas of lowest porosity in the basal sandstone aquifer, low porosity taken as an indicator of the lowest groundwater flow velocity and contaminant migration, are found in northeastern Indiana and northwestern Ohio, central and southeastern Indiana, and central Kentucky; (4) the thickest confining units that directly overlie the basal sandstone aquifer are found in central Kentucky and eastern Indiana where their thickness exceeds 500 ft; (5) steeply dipping faults that form potential hydraulic connections between crystalline rock, the basal sandstone aquifer, and the freshwater circulation system occur on the boundaries of the study area mainly in central Kentucky and central Indiana. Collectively, these data indicate that the hydrogeology of the sedimentary rocks in the western part of the study area is more favorably suited than that in the remainder of the area for the application of the buried crystalline-rock concept. (USGS)

  13. Experimental determination of the minimum onset temperature of runaway reaction from a radioactive salt disposal in asphalt.

    PubMed

    Li, Xin-Rui; Sun, Jin-Hua; Koseki, Hiroshi; Hasegawa, Kazutoshi

    2005-04-11

    In order to clarify the reason for the most hazardous explosion in the history of the Japanese nuclear power development by a radioactive salt disposal in asphalt, an adiabatic process was developed using a Dewar vessel to minimize the temperature difference between the reactants and the surroundings. By this means, the heat evolution from a reaction which is readily lost can be detected at a lower temperature imitating the accidental condition. A series of ambient temperature-tracking Dewar experiments on asphalt salt mixtures were conducted under different initial ambient temperatures, such as 230, 210, 190, and 170 degrees C, respectively. As a result, it was observed that from 190 degrees C the sample's temperature rose until a runaway reaction occurred. The minimum onset temperature for the runaway reaction of the asphalt salt mixture was determined to be 190 degrees C, which is close to the initial temperature of approximately 180 degrees C, the same temperature as the real accident. This implies that at near this operational temperature, initial faint chemical reactions may occur and lead to further rapid reactions if heat is accumulated at this stage. PMID:15811664

  14. Intruder dose pathway analysis for the onsite disposal of radioactive wastes: The ONSITE/MAXI1 computer program

    SciTech Connect

    Kennedy, W.E. Jr.; Peloquin, R.A.; Napier, B.A.; Neuder, S.M.

    1987-02-01

    This document summarizes initial efforts to develop human-intrusion scenarios and a modified version of the MAXI computer program for potential use by the NRC in reviewing applications for onsite radioactive waste disposal. Supplement 1 of NUREG/CR-3620 (1986) summarized modifications and improvements to the ONSITE/MAXI1 software package. This document summarizes a modified version of the ONSITE/MAXI1 computer program. This modified version of the computer program operates on a personal computer and permits the user to optionally select radiation dose conversion factors published by the International Commission on Radiological Protection (ICRP) in their Publication No. 30 (ICRP 1979-1982) in place of those published by the ICRP in their Publication No. 2 (ICRP 1959) (as implemented in the previous versions of the ONSITE/MAXI1 computer program). The pathway-to-human models used in the computer program have not been changed from those described previously. Computer listings of the ONSITE/MAXI1 computer program and supporting data bases are included in the appendices of this document.

  15. Survey of degradation modes of candidate materials for high-level radioactive-waste disposal containers; Overview

    SciTech Connect

    Farmer, J.C.; McCright, R.D.; Kass, J.N.

    1988-06-01

    Three iron- to nickel-based austenitic alloys and three copper-based alloys are being considered as candidate materials for the fabrication of high-level radioactive-waste disposal containers. The austenitic alloys are Types 304L and 316L stainless steels and the high-nickel material Alloy 825. The copper-based alloys are CDA 102 (oxygen-free copper), CDA 613 (Cu-7Al), and CDA 715 (Cu-30Ni). Waste in the forms of both spent fuel assemblies from reactors and borosilicate glass will be sent to the prospective repository at Yucca Mountain, Nevada. The decay of radionuclides will result in the generation of substantial heat and gamma radiation. Container materials may undergo any of several modes of degradation in this environment, including undesirable phase transformations due to a lack of phase stability; atmospheric oxidation; general aqueous corrosion; pitting; crevice corrosion; intergranular stress corrosion cracking; and transgranular stress corrosion cracking. Problems specific to welds, such as hot cracking, may also occur. A survey of the literature has been prepared as part of the process of selecting, from among the candidates, a material that is adequate for repository conditions. The modes of degradation are discussed in detail in the survey to determine which apply to the candidate alloys and the extent to which they may actually occur. The eight volumes of the survey are summarized in Sections 1 through 8 of this overview. The conclusions drawn from the survey are also given in this overview.

  16. Radionuclide Concentration in Soils and Vegetation at Low-Level Radioactive Waste Disposal Area G during 2005

    SciTech Connect

    P.R. Fresquez; M.W. McNaughton; M.J. Winch

    2005-10-01

    Soil samples were collected at 15 locations and unwashed overstory and understory vegetation samples were collected from up to nine locations within and around the perimeter of Area G, the primary disposal facility for low-level radioactive solid waste at Los Alamos National Laboratory (LANL). Soil and plant samples were also collected from the proposed expansion area west of Area G for the purpose of gaining preoperational baseline data. Soil and plant samples were analyzed for radionuclides that have shown a history of detection in past years; these included {sup 3}H, {sup 238}Pu, {sup 239,240}Pu, {sup 241}Am, {sup 234}U, {sup 235}U, and {sup 238}U for soils and {sup 3}H, {sup 238}Pu, and {sup 239,240}Pu for plants. As in previous years, the highest levels of {sup 3}H in soils and vegetation were detected at the south portion of Area G near the {sup 3}H shafts; whereas, the highest concentrations of the Pu isotopes were detected in the northern and northeastern portions near the pads for transuranic waste. All concentrations of radionuclides in soils and vegetation, however, were still very low (pCi range) and far below LANL screening levels and regulatory standards.

  17. Modular Design of Processing and Storage Facilities for Small Volumes of Low and Intermediate Level Radioactive Waste including Disused Sealed Sources - 12372

    SciTech Connect

    Keene, David R.; Kumar Samanta, Susanta; Drace, Zoran

    2012-07-01

    There are a number of IAEA Member States generating relatively small quantities of radioactive waste and/or disused sealed sources in application of nuclear techniques in medicine, industry and research and in nuclear research centres having small research reactors. At present many of these Member States do not have facilities for processing and storing their radioactive wastes; notably in those countries with small quantities of generated radioactive wastes. In other Member States the existing waste processing and storage facilities (WPSF) are in need of varying degrees of upgrading in order to address new waste streams, incorporate new waste processing technologies, or expand interim storage capacities. The IAEA has developed a modular design approach for a WPSF that is based on a variety of modules for different waste stream treatment and conditioning processes. The modular WPSF design is elaborated in a substantial Design Engineering Package that will be published by IAEA as a technical report. The Design Engineering Package enables users to select the optimum waste processing and storage modules to meet their needs, and to specify the requirements for procurement of individual modules and their integration into a waste processing and storage facility. The Design Engineering Package is planned for publication by the IAEA in 2012 and is presented as: - A Design Engineering Package Summary document. - A supporting CD that contains: - Process module general specifications. - Process module interface specifications. - Design Engineering Package for process modules. - Sample technical specifications for design and construction of modular processing facility. - Design Engineering Package for storage modules. (authors)

  18. Geologic and hydrologic considerations for various concepts of high-level radioactive waste disposal in conterminous United States

    USGS Publications Warehouse

    Ekren, E.B.; Dinwiddie, G.A.; Mytton, J.W.; Thordarson, William; Weir, J.E., Jr.; Hinrichs, E.N.; Schroder, L.J.

    1974-01-01

    The purpose of this investigation is to evaluate and identify which geohydrologic environments in conterminous United States are best suited for various concepts or methods of underground disposal of high-level radioactive wastes and to establish geologic and hydrologic criteria that are pertinent to high-level waste disposal. The unproven methods of disposal include (1) a very deep drill hole (30,000-50,000 ft or 9,140-15,240 m), (2) a matrix of (an array of multiple) drill holes (1,000-20,000 ft or 305-6,100 m), (3) a mined chamber (1,000-10,000 ft or 305-3,050 m), (4) a cavity with separate manmade structures (1,000-10,000 ft or 305-3,050 m), and (5) an exploded cavity (2,000-20,000 ft or 610-6,100 m) o The geohydrologic investigation is made on the presumption that the concepts or methods of disposal are technically feasible. Field and laboratory experiments in the future may demonstrate whether or not any of the methods are practical and safe. All the conclusions drawn are tentative pending experimental confirmation. The investigation focuses principally on the geohydrologic possibilities of several methods of disposal in rocks other than salt. Disposal in mined chambers in salt is currently under field investigation, and this disposal method has been intensely investigated and evaluated by various workers under the sponsorship of the Atomic Energy Commission. Of the various geohydrologic factors that must be considered in the selection of optimum waste-disposal sites, the most important is hydrologic isolation to assure that the wastes will be safely contained within a small radius of the emplacement zone. To achieve this degree of hydrologic isolation, the host rock for the wastes must have very low permeability and the site must be virtually free of faults. In addition, the locality should be in (1) an area of low seismic risk where the possibility of large earthquakes rupturing the emplacement zone is very low, (2) where the possibility- of flooding by

  19. LIFETIME PREDICTIONS OF TOXIC AND RADIOACTIVE WASTE DISPOSAL AND REMEDIATION SCHEMES

    SciTech Connect

    D.J. Wesolowski; R.C. Ewing; J. Bruno

    2005-06-28

    order to have a significant impact on global carbon emissions, worldwide nuclear and other carbon-free energy sources would have to increase tenfold by 2050. If this increase came entirely from electrical power plants using the once-through nuclear fuel cycle, about 3,500 new 1-GW plants would be needed, that would generate enough spent fuel to fill a Yucca Mountain-sized repository every year. Though this extreme scenario is not likely to unfold, it seems inevitable that we need this source of energy, if the public can be assured that the operation of these plants, and the disposal of the wastes generated from their operation, can be made acceptably safe. The Yucca Mountain field trip provided an excellent opportunity for a diverse cross section of engineers and geoscientists to gain a clearer perspective on the nature and problems related to this particular type of repository. The symposium not only brought together a similar broad cross section of scientists and engineers, but provided a forum for comparing and contrasting different repository designs being considered throughout the world, different methods of assessing their performance characteristics, and the surprisingly broad array of geochemical inputs needed in order to succeed in this Grand Challenge.

  20. Operating Experience and Lessons Learned in the Use of Soft-Sided Packaging for Transportation and Disposal of Low Activity Radioactive Waste

    SciTech Connect

    Kapoor, A.; Gordon, S.; Goldston, W.

    2013-07-08

    This paper describes the operating experience and lessons learned at U.S. Department of Energy (DOE) sites as a result of an evaluation of potential trailer contamination and soft-sided packaging integrity issues related to the disposal of low-level and mixed low-level (LLW/MLLW) radioactive waste shipments. Nearly 4.3 million cubic meters of LLW/MLLW will have been generated and disposed of during fiscal year (FY) 2010 to FY 2015—either at commercial disposal sites or disposal sites owned by DOE. The LLW/MLLW is packaged in several different types of regulatory compliant packaging and transported via highway or rail to disposal sites safely and efficiently in accordance with federal, state, and local regulations and DOE orders. In 1999, DOE supported the development of LLW containers that are more volumetrically efficient, more cost effective, and easier to use as compared to metal or wooden containers that existed at that time. The DOE Idaho National Engineering and Environmental Laboratory (INEEL), working in conjunction with the plastic industry, tested several types of soft-sided waste packaging systems that meet U.S. Department of Transportation requirements for transport of low specific activity and surface contaminated objects. Since then, soft-sided packaging of various capacities have been used successfully by the decontamination and decommissioning (D&D) projects to package, transport, and dispose D&D wastes throughout the DOE complex. The joint team of experts assembled by the Energy Facility Contractors Group from DOE waste generating sites, DOE and commercial waste disposal facilities, and soft-sided packaging suppliers conducted the review of soft-sided packaging operations and transportation of these packages to the disposal sites. As a result of this evaluation, the team developed several recommendations and best practices to prevent or minimize the recurrences of equipment contamination issues and proper use of soft-sided packaging for transport

  1. Ground-water levels and precipitation data at the Maxey Flats low-level radioactive waste disposal site near Morehead, Kentucky, October 1988-September 2000

    USGS Publications Warehouse

    Zettwoch, Douglas D.

    2002-01-01

    The U.S. Geological Survey, in cooperation with the Kentucky Natural Resources and Environmental Protection Cabinet--Department for Environmental Protection--Division of Waste Management, has an ongoing program to monitor water levels at the Maxey Flats low-level radioactive waste disposal site near Morehead, Kentucky. Ground-water-level and precipitation data were collected from 112 wells and 1 rain gage at the Maxey Flats low-level radioactive waste disposal site during October 1988-September 2000. Data were collected on a semi-annual basis from 62 wells, continuously from 6 wells, and monthly or bimonthly from 44 wells (13 of which had continuous recorders installed for the period October 1998-September 2000). One tipping-bucket rain gage was used to collect data at the Maxey Flats site for the period October 1988-September 2000.

  2. Assessment of site conditions for disposal of low- and intermediate-level radioactive wastes: a case study in southern China.

    PubMed

    Yi, Shuping; Ma, Haiyi; Zheng, Chunmiao; Zhu, Xiaobin; Wang, Hua'an; Li, Xueshan; Hu, Xueling; Qin, Jianbo

    2012-01-01

    Near surface disposal of low- and intermediate-level radioactive wastes (LILW) requires evaluating the field conditions of the candidate site. However, assessment of the site conditions may be challenging due to the limited prior knowledge of some remote sites, and various multi-disciplinary data requirements at any given site. These situations arise in China as in the rest of the industrialized world, particularly since a regional strategy for LILW disposal has been implemented to protect humans and the environment. This paper presents a demonstration of the site assessment process through a case study focusing mainly on the geologic, hydrogeologic and geochemical characteristics of the candidate site. A joint on-site and laboratory investigation, supplemented by numerical modeling, was implemented in this assessment. Results indicate that no fault is present in the site area, although there are some minor joints and fractures, primarily showing a north-south trend. Most of the joints are filled with quartz deposits and would thus function hydraulically as impervious barriers. Investigation of local hydrologic boundaries has shown that the candidate site represents an essentially isolated hydrogeologic unit, and that little or no groundwater flow occurs across its boundaries on the north or east, or across the hilly areas to the south. Groundwater in the site area is recharged by precipitation and discharges primarily by evapo-transpiration and surface flow through a narrow outlet to the west. Groundwater flows slowly from the hilly area to the foot of the hills and discharges mainly into the inner brooks and marshes. Some groundwater circulates in deeper granite in a slower manner. The vadose zone in the site was investigated specially for their significant capability for restraining the transport of radionuclides. Results indicate that the vadose zone is up to 38m in thickness and is made up of alluvial clay soils and very highly weathered granite. The vadose

  3. Geology of the Williston basin, North Dakota, Montana, and South Dakota, with reference to subsurface disposal of radioactive wastes

    USGS Publications Warehouse

    Sandberg, C.A.

    1962-01-01

    The southern Williston basin, which underlies about 110,000 square miles #n North Dakota, South Dakota, and eastern Montana, is part of a large structural and sedimentary basin. Its surface is a flat to gently rolling plain, standing about 1,500 to 3,500 feet above sea level and locally studded by a few high buttes. The sedimentary sequence that fills the basin has a maximum thickness of about 16,700 feet and rests on Precambrian metamorphic rocks at depths of 500 to 13,900 feet below sea level. It contains rocks of every geologic system, from Cambrian to Quaternary. Rocks of Middle Cambrian through Middle Ordovician age are largely shale and sandstone, as much as 1,200 feet thick; rocks of Late Ordovician through Pennsylvanian age are largely limestone and dolomite, as much as 7,500 feet thick; and rocks of Permian through Tertiary age are predominantly shale and siltstone, as much as 8,000 feet thick. Pleistocene glacial drift mantles the northern and eastern parts of the area. Rocks of the Williston basin are gently folded and regional dips are 1? or less from the margins to the basin center. Dips on the flanks of the major anticlinal folds, the Nesson and cedar Creek anticlines and the Poplar and Bowdoin domes, generally are about 1? to 3? except on the steep west limb of the Cedar Creek anticline. The basin was shaped by Laramide orogeny during latest Cretaceous and early Tertiary time. Most of the present structural features, however, were initiated during the Precambrian and reactivated by several subsequent orogenies, of which the latest was the Laramide. The most important mineral resource of the area is oil, which is produced predominantly from the Paleozoic carbonate sequence and largely on three of the major anticlinal folds, and lignite, which is present near the surface in Paleocene rocks. The subsurface disposal of radioactive wastes at some places in the Williston basin appears to be geographically and geologically feasible. Many sites, at which

  4. Radionuclide Concentrations in soils an Vegetation at Low-Level Radioactive Waste Disposal Area G During 2004

    SciTech Connect

    P.R. Fresquez; E.A. Lopez

    2004-11-01

    Soil samples were collected at 15 locations and unwashed overstory and understory vegetation samples were collected at nine locations within and around the perimeter of Area G, the primary disposal facility for low-level radioactive solid waste at Los Alamos National Laboratory (LANL). These samples were analyzed for {sup 3}H, {sup 238}Pu, {sup 239,240}Pu, {sup 90}Sr, {sup 241}Am, {sup 137}Cs, {sup 234}U, {sup 235}U, and {sup 238}U. Soil samples collected at Area G contained detectable concentrations of 3H (27%), {sup 239,240}Pu (60%), {sup 238}Pu (40%), and {sup 241}Am (47%) above regional statistical reference levels (RSRLs). In contrast, the levels of {sup 137}Cs, {sup 90}Sr, and U in all of the soil samples at Area G were either nondetectable or within RSRLs. The highest levels of {sup 3}H in soils were detected in the southwestern portion of Area G near the {sup 3}H shafts, whereas the highest concentrations of the Pu isotopes were detected in the northern and northeastern portions. All concentrations of {sup 3}H and Pu in soils, however, were far below LANL screening action levels. As for vegetation, most radionuclides in/on plants were either nondetectable or within RSRLs. The exceptions were {sup 3}H in overstory and some understory vegetation, particularly in the southwestern portion of Area G, which correlated very well with the soils data in that area. Also, there was some foliar contamination from {sup 241}Am and Pu isotopes in/on a few plant samples--the highest concentrations occurring in the northern section of Area G.

  5. Thermal-Hydrology Simulations of Disposal of High-Level Radioactive Waste in a Single Deep Borehole

    SciTech Connect

    Hadgu, Teklu; Stein, Emily; Hardin, Ernest; Freeze, Geoffrey A.; Hammond, Glenn Edward

    2015-11-01

    Simulations of thermal-hydrology were carried out for the emplacement of spent nuclear fuel canisters and cesium and strontium capsules using the PFLOTRAN simulator. For the cesium and strontium capsules the analysis looked at disposal options such as different disposal configurations and surface aging of waste to reduce thermal effects. The simulations studied temperature and fluid flux in the vicinity of the borehole. Simulation results include temperature and vertical flux profiles around the borehole at selected depths. Of particular importance are peak temperature increases, and fluxes at the top of the disposal zone. Simulations of cesium and strontium capsule disposal predict that surface aging and/or emplacement of the waste at the top of the disposal zone reduces thermal effects and vertical fluid fluxes. Smaller waste canisters emplaced over a longer disposal zone create the smallest thermal effect and vertical fluid fluxes no matter the age of the waste or depth of emplacement.

  6. WASTE CONTAINER AND WASTE PACKAGE PERFORMANCE MODELING TO SUPPORT SAFETY ASSESSMENT OF LOW AND INTERMEDIATE-LEVEL RADIOACTIVE WASTE DISPOSAL.

    SciTech Connect

    SULLIVAN, T.

    2004-06-30

    Prior to subsurface burial of low- and intermediate-level radioactive wastes, a demonstration that disposal of the wastes can be accomplished while protecting the health and safety of the general population is required. The long-time frames over which public safety must be insured necessitates that this demonstration relies, in part, on computer simulations of events and processes that will occur in the future. This demonstration, known as a Safety Assessment, requires understanding the performance of the disposal facility, waste containers, waste forms, and contaminant transport to locations accessible to humans. The objective of the coordinated research program is to examine the state-of-the-art in testing and evaluation short-lived low- and intermediate-level waste packages (container and waste form) in near surface repository conditions. The link between data collection and long-term predictions is modeling. The objective of this study is to review state-of-the-art modeling approaches for waste package performance. This is accomplished by reviewing the fundamental concepts behind safety assessment and demonstrating how waste package models can be used to support safety assessment. Safety assessment for low- and intermediate-level wastes is a complicated process involving assumptions about the appropriate conceptual model to use and the data required to support these models. Typically due to the lack of long-term data and the uncertainties from lack of understanding and natural variability, the models used in safety assessment are simplistic. However, even though the models are simplistic, waste container and waste form performance are often central to the case for making a safety assessment. An overview of waste container and waste form performance and typical models used in a safety assessment is supplied. As illustrative examples of the role of waste container and waste package performance, three sample test cases are provided. An example of the impacts of

  7. The Waste Isolation Pilot Plant Deep Geological Repository: A Domestic and Global Blueprint for Safe Disposal of High-Level Radioactive Waste - 12081

    SciTech Connect

    Eriksson, Leif G.; Dials, George E.

    2012-07-01

    At the end of 2011, the world's first used/spent nuclear fuel and other long-lived high-level radioactive waste (HLW) repository is projected to open in 2020, followed by two more in 2025. The related pre-opening periods will be at least 40 years, as it also would be if USA's candidate HLW-repository is resurrected by 2013. If abandoned, a new HLW-repository site would be needed. On 26 March 1999, USA began disposing long-lived radioactive waste in a deep geological repository in salt at the Waste Isolation Pilot Plant (WIPP) site. The related pre-opening period was less than 30 years. WIPP has since been re-certified twice. It thus stands to reason the WIPP repository is the global proof of principle for safe deep geological disposal of long-lived radioactive waste. It also stands to reason that the lessons learned since 1971 at the WIPP site provide a unique, continually-updated, blueprint for how the pre-opening period for a new HLW repository could be shortened both in the USA and abroad. (authors)

  8. Performance Assessment of a Low-Level Radioactive Waste Disposal Site using GoldSim Integrated Systems Model

    NASA Astrophysics Data System (ADS)

    Merrell, G.; Singh, A.; Tauxe, J.; Perona, R.; Dornsife, W.; grisak, G. E.; Holt, R. M.

    2011-12-01

    Texas Commission on Environmental Quality has approved licenses for four landfills at the Waste Control Specialists (WCS) site located in Andrews County, West Texas. The site includes a hazardous waste landfill and three landfills for radioactive waste. An updated performance assessment is necessary prior to acceptance of waste at the landfills. The updated performance assessment a) provides for more realistic and flexible dose modeling capabilities, b) addresses all plausible release and accident scenarios as they relate to the performance objectives, c) includes impact of climate and hydrologic scenarios that may impact long-term performance of the landfill, d) addresses impact of cover naturalization and degradation on the landfill, and e) incorporates uncertainty and sensitivity analysis for critical parameters. For the updated performance assessment, WCS has developed an integrated systems level performance assessment model using the GoldSim platform. GoldSim serves as a model for integrating all of the major components of a performance assessment, which include the radionuclide source term, facility design, environmental transport pathways, exposure scenarios, and radiological doses. Unlike many computer models that are based on first principles, GoldSim is a systems level model that can be used to integrate and abstract more complex sub-models into one system. This can then be used to assess the results into a unified model of the disposal system and environment. In this particular application, the GoldSim model consists of a) hydrogeologic model that simulates flow and transport through the Dockum geologic unit that underlies all of the waste facilities, b) waste cells that represent the containment unit and simulate degradation of waste forms, radionuclide leaching, and partitioning into the liquid and vapor phase within the waste unit, c) a cover system model that simulates upward diffusive transport from the underground repository to the atmosphere. In

  9. The consideration of geological uncertainty in the siting process for a Geological Disposal Facility for radioactive waste

    NASA Astrophysics Data System (ADS)

    Mathers, Steve; McEvoy, Fiona; Shaw, Richard

    2015-04-01

    Any decision about the site of a Geological Disposal Facility at depth for medium to high level radioactive waste is based on a safety case which in turn is based on an understanding of the geological environment which enables, for example, understanding groundwater flows and groundwater chemical composition. Because the information on which geological understanding is based cannot be fully understood, it is important to ensure that: i. Inferences are made from data in a way that is consistent with the data. ii. The uncertainty in the inferred information is described, quantitatively where this is appropriate. Despite these uncertainties decisions can and must be made, and so the implications of the uncertainty need to be understood and quantified. To achieve this it is important to ensure that: i. An understanding of how error propagates in all models and decision tools. Information which is collected to support the decision-making process may be used as input into models of various kinds to generate further information. For example, a process model may be used to predict groundwater flows, so uncertainty in the properties which are input to the model (e.g. on rock porosity and structure) will give rise to uncertainty in the model predictions. Understanding how this happens is called the analysis of error propagation. It is important that there is an understanding of how error propagates in all models and decision tools, and therefore knowledge of how much uncertainty remains in the process at any stage. As successive phases of data collection take place the analysis of error propagation shows how the uncertainty in key model outputs is gradually reduced. ii. The implications of all uncertainties can be traced through the process. A clear analysis of the decision-making process is necessary so that the implications of all uncertainties can be traced through the process. This means that, when a final decision is made, one can state with a high level of confidence

  10. Iraq nuclear facility dismantlement and disposal project (NDs Project).

    SciTech Connect

    Cochran, John Russell

    2010-06-01

    The Al Tuwaitha nuclear complex near Baghdad contains a number of facilities from Saddam Hussan's nuclear weapons program. Past military operations, lack of upkeep and looting have created an enormous radioactive waste problem at the Al Tuwaitha complex, which contains various, uncharacterized radioactive wastes, yellow cake, sealed radioactive sources, and contaminated metals that must be constantly guarded. Iraq has never had a radioactive waste disposal facility and the lack of a disposal facility means that ever increasing quantities of radioactive material must be held in guarded storage. The Iraq Nuclear Facility Dismantlement and Disposal Program (the NDs Program) has been initiated by the U.S. Department of State (DOS) to assist the Government of Iraq (GOI) in eliminating the threats from poorly controlled radioactive materials, while building human capacities so that the GOI can manage other environmental cleanups in their country. The DOS is funding the IAEA to provide technical assistance via Technical Cooperation projects. Program coordination will be provided by the DOS, consistent with GOI policies, and Sandia National Laboratories will be responsible for coordination of participants and waste management support. Texas Tech University will continue to provide in-country assistance, including radioactive waste characterization and the stand-up of the Iraq Nuclear Services Company. The GOI owns the problems in Iraq and will be responsible for implementation of the NDs Program.

  11. [Hospital and environment: waste disposal].

    PubMed

    Faure, P; Rizzo Padoin, N

    2003-11-01

    Like all production units, hospitals produce waste and are responsible for waste disposal. Hospital waste is particular due to the environmental risks involved, particularly concerning infection, effluents, and radionucleide contamination. Management plans are required to meet environmental, hygiene and regulatory obligations and to define reference waste products. The first step is to optimize waste sorting, with proper definition of the different categories, adequate containers (collection stations, color-coded sacks), waste circuits, intermediate then central storage areas, and finally transfer to an incineration unit. Volume and delay to elimination must be carefully controlled. Elimination of drugs and related products is a second aspect: packaging, perfusion pouches, tubing, radiopharmaceutic agents. These later products are managed with non-sealed sources whose elimination depends on the radioactive period, requiring selective sorting and specific holding areas while radioactivity declines. Elimination of urine and excreta containing anti-cancer drugs or intravesical drugs, particularly coming from protected rooms using radioactive iodine is another aspect. There is also a marginal flow of unused or expired drugs. For a health establishment, elimination of drugs is not included as part of waste disposal. This requires establishing a specific circuit with selective sorting and carefully applied safety regulations. Market orders for collecting and handling hospital wastes must be implemented in compliance with the rules of Public Health Tenders. PMID:14639187

  12. Corrective Action Investigation Plan for Corrective Action Unit 545: Dumps, Waste Disposal Sites, and Buried Radioactive Materials Nevada Test Site, Nevada, Revision 0

    SciTech Connect

    Wickline, Alfred

    2007-06-01

    Corrective Action Unit 545, Dumps, Waste Disposal Sites, and Buried Radioactive Materials, consists of seven inactive sites located in the Yucca Flat area and one inactive site in the Pahute Mesa area. The eight CAU 545 sites consist of craters used for mud disposal, surface or buried waste disposed within craters or potential crater areas, and sites where surface or buried waste was disposed. The CAU 545 sites were used to support nuclear testing conducted in the Yucca Flat area during the 1950s through the early 1990s, and in Area 20 in the mid-1970s. This Corrective Action Investigation Plan has been developed in accordance with the Federal Facility Agreement and Consent Order that was agreed to by the State of Nevada, the U.S. Department of Energy, and the U.S. Department of Defense. Under the Federal Facility Agreement and Consent Order, this Corrective Action Investigation Plan will be submitted to the Nevada Division of Environmental Protection for approval. Fieldwork will be conducted following approval.

  13. Effects on radionuclide concentrations by cement/ground-water interactions in support of performance assessment of low-level radioactive waste disposal facilities

    SciTech Connect

    Krupka, K.M.; Serne, R.J.

    1998-05-01

    The US Nuclear Regulatory Commission is developing a technical position document that provides guidance regarding the performance assessment of low-level radioactive waste disposal facilities. This guidance considers the effects that the chemistry of the vault disposal system may have on radionuclide release. The geochemistry of pore waters buffered by cementitious materials in the disposal system will be different from the local ground water. Therefore, the cement-buffered environment needs to be considered within the source term calculations if credit is taken for solubility limits and/or sorption of dissolved radionuclides within disposal units. A literature review was conducted on methods to model pore-water compositions resulting from reactions with cement, experimental studies of cement/water systems, natural analogue studies of cement and concrete, and radionuclide solubilities experimentally determined in cement pore waters. Based on this review, geochemical modeling was used to calculate maximum concentrations for americium, neptunium, nickel, plutonium, radium, strontium, thorium, and uranium for pore-water compositions buffered by cement and local ground-water. Another literature review was completed on radionuclide sorption behavior onto fresh cement/concrete where the pore water pH will be greater than or equal 10. Based on this review, a database was developed of preferred minimum distribution coefficient values for these radionuclides in cement/concrete environments.

  14. Well-construction and hydrogeologic data for observation wells in the vicinity of a low-level radioactive-waste disposal site near Sheffield, Illinois

    USGS Publications Warehouse

    Mansue, Lawrence J.; Mills, Patrick C.

    1991-01-01

    The U.S. Geological Survey conducted hydrogeologic studies at the low-level radioactive-waste disposal site near Sheffield, Illinois, from 1976 through 1987. During that period, 108 observation wells were installed in the vicinity of the disposal site in glacial and post-glacial deposits of Quaternary age and bedrock of Pennsylvanian age. Data in this report include the location of each well, the date each well was drilled, the geologic units penetrated by each well, the physical measurements of each well, the elevations of the top (measuring point) of each well and geologic-unit contacts at each well, and the highest and lowest recorded water levels in each well.

  15. Acoustic Seal

    NASA Technical Reports Server (NTRS)

    Steinetz, Bruce M. (Inventor)

    2006-01-01

    The invention relates to a sealing device having an acoustic resonator. The acoustic resonator is adapted to create acoustic waveforms to generate a sealing pressure barrier blocking fluid flow from a high pressure area to a lower pressure area. The sealing device permits noncontacting sealing operation. The sealing device may include a resonant-macrosonic-synthesis (RMS) resonator.

  16. Acoustic seal

    NASA Technical Reports Server (NTRS)

    Steinetz, Bruce M. (Inventor)

    2006-01-01

    The invention relates to a sealing device having an acoustic resonator. The acoustic resonator is adapted to create acoustic waveforms to generate a sealing pressure barrier blocking fluid flow from a high pressure area to a lower pressure area. The sealing device permits noncontacting sealing operation. The sealing device may include a resonant-macrosonic-synthesis (RMS) resonator.

  17. Fluid sealing

    SciTech Connect

    Nau, B.S.

    1987-01-01

    This book contains 41 papers. Some of the titles are: Evaluation of secondary containment seals for pumps on hydrocarbon duties; Valve steam sealing in nuclear plants; Design directives for liquid spattered labyrinth seals; Analysis of a novel rotary seal; Contacting mechanical seal design using a simplified hydrostatic model; and Transient thermoelastic effects in a mechanical face.

  18. Repository seals requirements study

    SciTech Connect

    1997-11-03

    The Yucca Mountain Site Characterization Project, managed by the Civilian Radioactive Waste Management System (CRWMS) Management and Operating Contractor (M and O) is conducting investigations to support the Viability Assessment and the License Application for a high-level nuclear waste repository at Yucca Mountain, Nevada. The sealing subsystem is part of the Yucca Mountain Waste Isolation System. The Yucca Mountain Site Characterization Project is currently evaluating the role of the sealing subsystem (shaft, ramp and exploratory borehole seals) in achieving the overall performance objectives for the Waste Isolation System. This report documents the results of those evaluations. This report presents the results of a repository sealing requirements study. Sealing is defined as the permanent closure of the shafts, ramps, and exploratory boreholes. Sealing includes those components that would reduce potential inflows above the repository, or that would divert flow near the repository horizon to allow vertical infiltration to below the repository. Sealing of such features as emplacement drifts was not done in this study because the current capability to calculate fracture flow into the drifts is not sufficiently mature. The objective of the study is to provide water or air flow performance based requirements for shafts, ramps, and exploratory boreholes located near the repository. Recommendations, as appropriate, are provided for developing plans, seals component testing, and other studies relating to sealing.

  19. A Monte Carlo procedure for the construction of complementary cumulative distribution functions for comparison with the EPA release limits for radioactive waste disposal

    SciTech Connect

    Helton, J.C.; Shiver, A.W.

    1994-10-01

    A Monte Carlo procedure for the construction of complementary cumulative distribution functions (CCDFs) for comparison with the US Environmental Protection Agency (EPA) release limits for radioactive waste disposal (40 CFR 191, Subpart B) is described and illustrated with results from a recent performance assessment (PA) for the Waste Isolation Pilot Plant (WIPP). The Monte Carlo procedure produces CCDF estimates similar to those obtained with stratified sampling in several recent PAs for the WIPP. The advantages of the Monte Carlo procedure over stratified sampling include increased resolution in the calculation of probabilities for complex scenarios involving drilling intrusions and better use of the necessarily limited number of mechanistic calculations that underlie CCDF construction.

  20. A user's guide to the GoldSim/BLT-MS integrated software package:a low-level radioactive waste disposal performance assessment model.

    SciTech Connect

    Knowlton, Robert G.; Arnold, Bill Walter; Mattie, Patrick D.

    2007-03-01

    Sandia National Laboratories (Sandia), a U.S. Department of Energy National Laboratory, has over 30 years experience in the assessment of radioactive waste disposal and at the time of this publication is providing assistance internationally in a number of areas relevant to the safety assessment of radioactive waste disposal systems. In countries with small radioactive waste programs, international technology transfer program efforts are often hampered by small budgets, schedule constraints, and a lack of experienced personnel. In an effort to surmount these difficulties, Sandia has developed a system that utilizes a combination of commercially available software codes and existing legacy codes for probabilistic safety assessment modeling that facilitates the technology transfer and maximizes limited available funding. Numerous codes developed and endorsed by the United States Nuclear Regulatory Commission (NRC) and codes developed and maintained by United States Department of Energy are generally available to foreign countries after addressing import/export control and copyright requirements. From a programmatic view, it is easier to utilize existing codes than to develop new codes. From an economic perspective, it is not possible for most countries with small radioactive waste disposal programs to maintain complex software, which meets the rigors of both domestic regulatory requirements and international peer review. Therefore, revitalization of deterministic legacy codes, as well as an adaptation of contemporary deterministic codes, provides a credible and solid computational platform for constructing probabilistic safety assessment models. This document is a reference users guide for the GoldSim/BLT-MS integrated modeling software package developed as part of a cooperative technology transfer project between Sandia National Laboratories and the Institute of Nuclear Energy Research (INER) in Taiwan for the preliminary assessment of several candidate low

  1. 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.

  2. Geologic and hydrologic data collected during 1976-1983 at the Sheffield low-level radioactive waste disposal site and adjacent areas, Sheffield, Illinois

    USGS Publications Warehouse

    Foster, J.B.; Garklavs, George; Mackey, G.W.

    1984-01-01

    Hydrogeologic studies were conducted at the low-level radioactive-waste disposal site near Sheffield, Illinois, from 1976-84. Data in this report include water levels in wells, lake stages, inorganic, organic, and radiometric chemical analyses of ground and surface water, hydraulic conductivities of glacial materials, grain-size distribution, clay and carbonate mineralogy, and cation exchange capacities of the glacial materials. Also included are results of petrographic analyses, physical measurements of wells, stratigraphy and lithology of cores collected from test wells, and horizontal coordinates of wells.

  3. Historical perspective, economic analysis, and regulatory analysis of the impacts of waste partitioning-transmutation on the disposal of radioactive wastes

    SciTech Connect

    Forsberg, C.W.; Croff, A.G.; Kocher, D.C.

    1990-10-01

    Partitioning-transmutation, sometimes called actinide burning, is an alternative approach to high-level radioactive waste management. It consists of removing long-lived radionuclides from wastes and destroying those radionuclides, thus reducing the long-term hazards of radioactive waste. It was studied in detail in the 1970's. New developments in technology and other factors are resulting in a reexamination of this waste management option. This report consists of three papers which summarize the historical work, update the analysis of the costs of waste disposal, and describe current regulatory requirements which might be impacted by P-T. The papers provide a starting point for future research on P-T. 152 refs., 2 figs., 19 tabs.

  4. Fate and bioaccumulation of soil-associated low-level naturally occurring radioactivity following disposal into a marine ecosystem. Final report

    SciTech Connect

    Hunt, C.D.

    1986-10-01

    The fate of radium (Ra) and other naturally occurring uranium-series isotopes associated with soils disposed in seawater was examined using the Marine Ecosystem Research Laboratory (MERL) controlled marine ecosystems. Thirty-seven kilograms of a soil containing approximately 400 pCi Ra-226/g from an inactive uranium ore processing plant site in Middlesex, New Jersey, were added to each of two mesocosms over five days in mid-September 1984. Radionuclide activity in these and two control mesocosms was observed for three months after the soil additions. Radioactivity in the soil appeared to be confined to discrete soil particles rather than being distributed equally on the soil particles, suggesting the source of the radioactivity was remnant ore particles.

  5. Repository seals requirement study

    SciTech Connect

    1997-11-03

    The Yucca Mountain Site Characterization Project, managed by the Civilian Radioactive Waste Management System (CRWMS) Management and Operating Contractor (M and O) is conducting investigations to support the Viability Assessment and the License Application for a high-level nuclear waste repository at Yucca Mountain, Nevada. The sealing subsystem is part of the Yucca Mountain Waste Isolation System. The Yucca Mountain Site Characterization Project is currently evaluating the role of the sealing subsystem (shaft, ramp and exploratory borehole seals) in achieving the overall performance objectives for the Waste Isolation System. This report documents the results of those evaluations. The objective of the study is to provide water or air flow performance based requirements for shafts, ramps, and exploratory boreholes located near the repository. Recommendations, as appropriate, are provided for developing plans, seals component testing, and other studies relating to sealing.

  6. Integration of US Department of Energy contractor installations for the purpose of optimizing treatment, storage, and disposal of low-level radioactive waste (LLW)

    SciTech Connect

    Lucas, M.; Gnoose, J.; Coony, M.; Martin, E.; Piscitella, R.

    1998-02-01

    The US Department of Energy (DOE) manages a multibillion dollar environmental management (EM) program. In June 1996, the Assistant Secretary of Energy for EM issued a memorandum with guidance and a vision for a ten year planning process for the EM Program. The purpose of this process, which became known as the Accelerated Cleanup: Focus on 2006, is to make step changes within the DOE complex regarding the approach for making meaningful environmental cleanup progress. To augment the process, Assistant Secretary requested the site contractors to engage in an effort to identify and evaluate integration alternatives for EM waste stream treatment, storage, and disposal (TSD) that would parallel the 2006 Plan. In October 1996, ten DOE contractor installations began the task of identifying alternative opportunities for low level radioactive waste (LLW). Cost effective, efficient solutions were necessary to meet all requirements associated with storing, characterizing, treating, packaging, transporting, and disposing of LLW while protecting the workers` health and safety, and minimizing impacts to the environment. To develop these solutions, a systems engineering approach was used to establish the baseline requirements, to develop alternatives, and to evaluate the alternatives. Key assumptions were that unique disposal capabilities exist within the DOE that must be maintained; private sector disposal capability for some LLW may not continue to exist into the foreseeable future; and decisions made by the LLW Team must be made on a system or complex wide basis to fully realize the potential cost and schedule benefits. This integration effort promoted more accurate waste volume estimates and forecasts; enhanced recognition of existing treatment, storage, and disposal capabilities and capacities; and improved identification of cost savings across the complex.

  7. Tritium Fluxes through the Shallow Unsaturated Zone adjacent to a Radioactive Waste Disposal Facility in an Arid Environment

    NASA Astrophysics Data System (ADS)

    Maples, S.; Andraski, B. J.; Stonestrom, D. A.; Cooper, C. A.; Pohll, G.

    2011-12-01

    Studies at the U.S. Geological Survey's Amargosa Desert Research Site (ADRS) in southern Nevada have documented long-distance (>400-m) tritium (3H) transport adjacent to a commercial, low-level radioactive waste disposal facility. Transport at this scale is orders of magnitude greater than anticipated; however, lateral 3H fluxes through the shallow unsaturated zone (UZ) have not been investigated in detail. The objective of this study is to estimate and compare lateral and vertical tritiated water-vapor (3HHOg) fluxes in the shallow UZ and their relation to the observed plume migration. Previous studies have recognized two distinct plumes of 3H emanating from the facility. Shallow (0.5 and 1.5-m depth) soil-water vapor samples were collected yearly along 400-m long transects through both plumes from 2003-09. Within the south plume, 3H concentrations at 1.5-m depth have decreased by 44 ± 0.3% during this period, and plume advancement there has effectively ceased (i.e., rate of advance equals rate of decay). During the same period, the west plume showed a net decrease in concentration of 34 ± 0.9% within 100-m of the facility; however, plume advancement is observed at the leading edge of the plume, and concentrations 200-300-m from the facility show an increase in 3H concentration of 64 ± 28.4%. Lateral and vertical diffusive fluxes within both plumes were calculated using 3HHOg concentrations from 2006. Lateral 3HHOg diffusive fluxes within both plumes have been estimated 25-300-m from the facility at 1.5-m depth. Mean lateral 3HHOg diffusive fluxes are 10-14 g m-2 yr-1 within the south plume, and 10-13 g m-2 yr-1 within the west plume. Mean lateral fluxes in the south plume are an order of magnitude lower than in the west plume. This behavior corresponds with the observed relative immobility of the south plume, while the elevated west plume fluxes agree with the plume advancement seen there. Shallow, upward directed, mean vertical 3HHOg fluxes 25-300-m from the

  8. Source inventory for Department of Energy solid low-level radioactive waste disposal facilities: What it means and how to get one of your own

    SciTech Connect

    Smith, M.A.

    1991-12-31

    In conducting a performance assessment for a low-level waste (LLW) disposal facility, one of the important considerations for determining the source term, which is defined as the amount of radioactivity being released from the facility, is the quantity of radioactive material present. This quantity, which will be referred to as the source inventory, is generally estimated through a review of historical records and waste tracking systems at the LLW facility. In theory, estimating the total source inventory for Department of Energy (DOE) LLW disposal facilities should be possible by reviewing the national data base maintained for LLW operations, the Solid Waste Information Management System (SWIMS), or through the annual report that summarizes the SWIMS data, the Integrated Data Base (IDB) report. However, in practice, there are some difficulties in making this estimate. This is not unexpected, since the SWIMS and the IDB were not developed with the goal of developing a performance assessment source term in mind. The practical shortcomings using the existing data to develop a source term for DOE facilities will be discussed in this paper.

  9. Intruder dose pathway analysis for the onsite disposal of radioactive wastes: the ONSITE/MAXI1 computer program. Supplement No. 1

    SciTech Connect

    Kennedy, W.E. Jr.; Peloquin, R.A.; Napier, B.A.; Neuder, S.M.

    1986-05-01

    The document entitled Intruder Dose Pathway Analysis of the Onsite Disposal of Radioactive Wastes: The ONSITE/MAXI1 Computer Program (1984) summarizes initial efforts to develop human-intrustion scenarios and a modified version of the MAXI computer program for potential use by the NRC in reviewing applications for onsite radioactive waste disposal. This document is a supplement to that document and summarizes efforts to further modify and improve the ONSITE/MAXI1 software package. To facilitate cross-referencing, it follows the same format. Notable improvements to the software package include the capability to account for shielding conditions that represent noncompacted trash wastes and the option to indicate alternative land-use condition;s. This supplement contains a description of the implementation of these modifications. In addition, a series of discussions are included in an attempt to increase the user's understanding of the scenarios and dose calculation methods. These discussions respond to frequently asked questions about the mathematical models and use of the software. Computer listings of the ONSITE/MAXI1 computer program are included as Appendices A and B of this document. Appendix C lists external exposure dose-rate factor libraries.

  10. Status on disposal of greater-than-Class C

    SciTech Connect

    Plummer, T.L.

    1995-12-31

    The Department of Energy (DOE) has developed a plan for the management and disposal of commercially generated greater-than-Class C (GTCC) low-level radioactive waste. The Low-Level Radioactive Waste Policy Amendments Act of 1985 made DOE responsible for disposal of GTCC waste. The act requires that GTCC waste be disposed in a Nuclear Regulatory Commission (NRC)-licensed facility. The NRC has amended 10 CFR 61 to express a preference for geologic disposal of GTCC waste. Based on reassessment studies, legislative guidance, and stakeholder involvement, a revised plan has been formulated to provide for total management of GTCC waste. The plan has four major thrusts: (1) plan for GTCC waste storage at the generator site until disposal is available, (2) establish storage for GTCC sealed sources posing health and safety risk to the public, (3) facilitate storage for other GTCC waste posing health and safety risk to the public, and (4) plan for co-disposal of GTCC waste in a geologic disposal site with similar waste types. The revised plan focuses on applying available resources to near- and long-term needs.

  11. Regional geological assessment of the Devonian-Mississippian shale sequence of the Appalachian, Illinois, and Michigan basins relative to potential storage/disposal of radioactive wastes

    SciTech Connect

    Lomenick, T.F.; Gonzales, S.; Johnson, K.S.; Byerly, D.

    1983-01-01

    The thick and regionally extensive sequence of shales and associated clastic sedimentary rocks of Late Devonian and Early Mississippian age has been considered among the nonsalt geologies for deep subsurface containment of high-level radioactive wastes. This report examines some of the regional and basin-specific characteristics of the black and associated nonblack shales of this sequence within the Appalachian, Illinois, and Michigan basins of the north-central and eastern United States. Principal areas where the thickness and depth of this shale sequence are sufficient to warrant further evaluation are identified, but no attempt is made to identify specific storage/disposal sites. Also identified are other areas with less promise for further study because of known potential conflicts such as geologic-hydrologic factors, competing subsurface priorities involving mineral resources and groundwater, or other parameters. Data have been compiled for each basin in an effort to indicate thickness, distribution, and depth relationships for the entire shale sequence as well as individual shale units in the sequence. Included as parts of this geologic assessment are isopach, depth information, structure contour, tectonic elements, and energy-resource maps covering the three basins. Summary evaluations are given for each basin as well as an overall general evaluation of the waste storage/disposal potential of the Devonian-Mississippian shale sequence,including recommendations for future studies to more fully characterize the shale sequence for that purpose. Based on data compiled in this cursory investigation, certain rock units have reasonable promise for radioactive waste storage/disposal and do warrant additional study.

  12. New regulations for radiation protection for work involving radioactive fallout emitted by the TEPCO Fukushima Daiichi APP accident--disposal of contaminated soil and wastes.

    PubMed

    Yasui, Shojiro

    2014-01-01

    The accident at the Fukushima Daiichi Atomic Power Plant that accompanied the Great East Japan Earthquake on March 11, 2011, released a large amount of radioactive material. To rehabilitate the contaminated areas, the government of Japan decided to carry out decontamination work and manage the waste resulting from decontamination. In the summer of 2013, the Ministry of the Environment planned to begin a full-scale process for waste disposal of contaminated soil and wastes removed as part of the decontamination work. The existing regulations were not developed to address such a large amount of contaminated wastes. The Ministry of Health, Labour and Welfare (MHLW), therefore, had to amend the existing regulations for waste disposal workers. The amendment of the general regulation targeted the areas where the existing exposure situation overlaps the planned exposure situation. The MHLW established the demarcation lines between the two regulations to be applied in each situation. The amendment was also intended to establish provisions for the operation of waste disposal facilities that handle large amounts of contaminated materials. Deliberation concerning the regulation was conducted when the facilities were under design; hence, necessary adjustments should be made as needed during the operation of the facilities. PMID:24856781

  13. Radiation protection recommendations as applied to the disposal of long-lived solid radioactive waste. A report of The International Commission on Radiological Protection.

    PubMed

    1998-01-01

    (79) Waste, by definition, has no benefit. It should be viewed as one aspect of the beneficial practice that gave rise to it. Furthermore, radioactive waste management should be placed in the context of the management of society's waste in general. (80) A major issue in evaluating the acceptability of a disposal system for long-lived solid radioactive waste is that doses or risks may arise from exposures in the distant future. There is uncertainty surrounding any estimate of these doses or risks due to lack of knowledge about future conditions. Such exposures are treated as potential exposures as their magnitude depends on future processes and conditions that have probabilities associated with them. (81) Nevertheless, the Commission recognises a basic principle that individuals and populations in the future should be afforded at least the same level of protection from the action of disposing of radioactive waste today as is the current generation. This implies use of the current quantitative dose and risk criteria derived from considering associated health detriment. Therefore, protection of future generations should be achieved by applying these dose or risk criteria to the estimated future doses or risks in appropriately defined critical groups. These estimates should not be regarded as measures of health detriment beyond times of around several hundreds of years into the future. In the case of these longer time periods, they represent indicators of the protection afforded by the disposal system. (82 Constrained optimisation is the central approach to evaluating the radiological acceptability of a waste disposal system; dose or risk constraints are used rather than dose or risk limits. By this transition from limitation to optimisation, the needs of practical application of the radiological protection system to the disposal of long-lived solid waste disposal are met: determination of acceptability now for exposures that may occur in the distant future

  14. Conical O-ring seal

    DOEpatents

    Chalfant, G.G. Jr.

    A shipping container for radioactive or other hazardous materials has a conical-shaped closure containing grooves in the conical surface thereof and an O-ring seal incorporated in each of such grooves. The closure and seal provide a much stronger, tighter and compact containment than with a conventional flanged joint.

  15. Conical O-ring seal

    DOEpatents

    Chalfant, Jr., Gordon G.

    1984-01-01

    A shipping container for radioactive or other hazardous materials which has a conical-shaped closure containing grooves in the conical surface thereof and an O-ring seal incorporated in each of such grooves. The closure and seal provide a much stronger, tighter and compact containment than with a conventional flanged joint.

  16. Three-Dimensional Geologic Modeling of a Prospective Deep Underground Laboratory Site for High-Level Radioactive Waste Disposal in Korea

    NASA Astrophysics Data System (ADS)

    Park, J. Y.; Lee, S.; Park, S. U.; Kim, J. M.; Kihm, J. H.

    2014-12-01

    A series of three-dimensional geologic modeling was performed using a geostatistical geologic model GOCAD (ASGA and Paradigm) to characterize quantitatively and to visualize realistically a prospective deep underground laboratory site for high-level radioactive waste disposal in Korea. The necessity of a deep underground laboratory arises from its in-situ conditions for related deep scientific experiments. However, the construction and operation of such a deep underground laboratory take great efforts and expenses owing to its larger depth and thus higher geologic uncertainty. For these reasons, quantitative characterization and realistic visualization of geologic formations and structures of a deep underground laboratory site is crucial before its construction and operation. The study area for the prospective deep underground laboratory site is mainly consists of Precambrian metamorphic rocks as a complex. First, various topographic and geologic data of the study area were collected from literature and boreholes and preliminarily analyzed. Based on the preliminary analysis results, a three-dimensional structural model, which consists of the boundaries between the geologic formations and structures, was established, and a three-dimensional grid model, which consists of hexahedral grid blocks, was produced. Three-dimensional geologic formation model was then established by polymerizing these two models. Finally, a series of three-dimensional lithofacies modeling was performed using the sequential indicator simulation (SIS) and truncated Gaussian simulation (TGS). The volume fractions of metamorphic rocks predicted using the TGS are more similar to the actual data observed in boreholes than those predicted using the SIS. These three-dimensional geologic modeling results can improve a quantitative and realistic understanding of geologic characteristics of the prospective deep underground laboratory site for high-level radioactive waste disposal and thus can provide

  17. Glass sealing

    SciTech Connect

    Brow, R.K.; Kovacic, L.; Chambers, R.S.

    1996-04-01

    Hernetic glass sealing technologies developed for weapons component applications can be utilized for the design and manufacture of fuel cells. Design and processing of of a seal are optimized through an integrated approach based on glass composition research, finite element analysis, and sealing process definition. Glass sealing procedures are selected to accommodate the limits imposed by glass composition and predicted calculations.

  18. Coining seal

    DOEpatents

    Mancebo, Lloyd

    1976-01-01

    A bakeable high pressure-vacuum seal is provided in which an inductile sealing element having a butterfly shaped crosssection with protruding sharp edges at each of the four corners, is sandwiched between two ductile sealing elements, the sandwiched assembly then being compressed between the surfaces of the flange elements of a high pressure or high vacuum vessel to coin the ductile sealing element into the surface of the inductile sealing element as well as the surfaces of the flange elements.

  19. Sealing device

    SciTech Connect

    Garcia-Crespo, Andres Jose

    2013-12-10

    A sealing device for sealing a gap between a dovetail of a bucket assembly and a rotor wheel is disclosed. The sealing device includes a cover plate configured to cover the gap and a retention member protruding from the cover plate and configured to engage the dovetail. The sealing device provides a seal against the gap when the bucket assemply is subjected to a centrifugal force.

  20. Internal coaxial cable seal system

    DOEpatents

    Hall, David R.; Sneddon, Cameron; Dahlgren, Scott Steven; Briscoe, Michael A.

    2006-07-25

    The invention is a seal system for a coaxial cable and is placed within the coaxial cable and its constituent components. A series of seal stacks including load ring components and elastomeric rings are placed on load bearing members within the coaxial cable sealing the annular space between the coaxial cable and an electrical contact passing there through. The coaxial cable is disposed within drilling components to transmit electrical signals between drilling components within a drill string. The seal system can be used in a variety of downhole components, such as sections of pipe in a drill string, drill collars, heavy weight drill pipe, and jars.

  1. Reactor cavity seal ring

    SciTech Connect

    Hankinson, M.F.

    1986-04-22

    A hydrostatic seal is described for sealing an annular gap between two flat substantially horizontal coplanar surfaces comprising, in combination: a generally flat annular plate of a width sufficient to span a gap between two surfaces: compressible annular sealing means disposed on the bottom surface of the flat annular plate for sealingly engaging the two flat surfaces in response to a downward force exerted on the plate; and fastening means, distributed along the center line of the plate, for releasably fastening the plate in a position to span the gap to be sealed and exert a downward force on the plate, each fastening means including a pair of elongated members of a size to fit into the gap to be sealed, means for mounting the members on the bottom surface of the plate so that at least a portion of each member is radially moveable in a direction toward a respective one of the vertical side surfaces defining the gap to be sealed to engage same and so that the plate is moveable relative to the members in a downward direction in response to hydrostatic pressure applied to the upper surface of the plate when the members are engaging the vertical side surfaces of an annular gap, and an actuating means, mounted on the plate for movement therewith in response to hydrostatic pressure, for radially moving the members, the actuating means extending through a bore in the plate to the upper surface of the plate.

  2. Alternative Evaluation Study: Methods to Mitigate/Accommodate Subsidence for the Radioactive Waste Management Sites at the Nevada Test Site, Nye County Nevada, with Special Focus on Disposal Cell U-3ax/bl

    SciTech Connect

    Barker, L.

    1997-09-01

    An Alternative Evaluation Study is a type of systematic approach to problem identification and solution. An Alternative Evaluation Study was convened August 12-15, 1997, for the purpose of making recommendations concerning closure of Disposal Cell U-3ax/bl and other disposal cells and mitigation/accommodation of waste subsidence at the Radioactive Waste Management Sites at the Nevada Test Site. This report includes results of the Alternative Evaluation Study and specific recommendations.

  3. Regulatory Requirements and Technical Analysis for Department of Energy Regulated Performance Assessments of Shallow-Trench Disposal of Low-Level Radioactive Waste at the Nevada Test Site

    NASA Astrophysics Data System (ADS)

    Crowe, B.; Black, P.; Tauxe, J.; Yucel, V.; Rawlinson, S.; Colarusso, A.; DiSanza, F.

    2001-12-01

    The National Nuclear Security Administration, Nevada Operations Office (NNSA/NV) operates and maintains two active facilities on the Nevada Test Site (NTS) that dispose Department of Energy (DOE) defense-generated low-level radioactive (LLW), mixed radioactive, and classified waste in shallow trenches, pits and large-diameter boreholes. The operation and maintenance of the LLW disposal sites are self-regulated under DOE Order 435.1, which requires review of a Performance Assessment for four performance objectives: 1) all pathways 25 mrem/yr limit; 2) atmospheric pathways 10 mrem/yr limit; 3) radon flux density of 20 pCi/m2/s; and 4) groundwater resource protection (Safe Drinking Water Act; 4 mrem/yr limit). The inadvertent human intruder is protected under a dual 500- and 100-mrem limit (acute and chronic exposure). In response to the Defense Nuclear Facilities Safety Board Recommendation 92 2, a composite analysis is required that must examine all interacting sources for compliance against both 30 and 100 mrem/yr limits. A small component of classified transuranic waste is buried at intermediate depths in 3-meter diameter boreholes at the Area 5 LLW disposal facility and is assessed through DOE-agreement against the requirements of the Environmental Protection Agency (EPA)'s 40 CFR 191. The hazardous components of mixed LLW are assessed against RCRA requirements. The NTS LLW sites fall directly under three sets of federal regulations and the regulatory differences result not only in organizational challenges, but also in different decision objectives and technical paths to completion. The DOE regulations require deterministic analysis for a 1,000-year compliance assessment supplemented by probabilistic analysis under a long-term maintenance program. The EPA regulations for TRU waste are probabilistically based for a compliance interval of 10,000 years. Multiple steps in the assessments are strongly dependent on assumptions for long-term land use policies

  4. Management of disused plutonium sealed sources

    SciTech Connect

    Whitworth, Julia Rose; Pearson, Michael W; Abeyta, Cristy

    2010-01-01

    The Global Threat Reduction Initiative's (GTRI) Offsite Source Recovery Project (OSRP) has been recovering excess and unwanted radioactive sealed sources since 1999, including more than 2,400 Plutonium (Pu)-238 sealed sources and 653 Pu-239-bearing sources that represent more than 10% of the total sources recovered by GTRI/OSRP to date. These sources have been recovered from hundreds of sites within the United States (US) and around the world. OSRP grew out of early efforts at the Los Alamos National Laboratory (LANL) to recover and disposition excess Plutonium-239 (Pu-239) sealed sources that were distributed in the 1960s and 1970s under the Atoms for Peace Program, a loan-lease program that serviced 31 countries, as well as domestic users. In the conduct of these recovery operations, GTRI/OSRP has been required to solve problems related to knowledge-of-inventory, packaging and transportation of fissile and heat-source materials, transfer of ownership, storage of special nuclear material (SNM) both at US Department of Energy (DOE) facilities and commercially, and disposal. Unique issues associated with repatriation from foreign countries, including end user agreements required by some European countries and denials of shipment, will also be discussed.

  5. Some logistical considerations in designing a system of deep boreholes for disposal of high-level radioactive waste.

    SciTech Connect

    Gray, Genetha Anne; Brady, Patrick Vane; Arnold, Bill Walter

    2012-09-01

    Deep boreholes could be a relatively inexpensive, safe, and rapidly deployable strategy for disposing Americas nuclear waste. To study this approach, Sandia invested in a three year LDRD project entitled %E2%80%9CRadionuclide Transport from Deep Boreholes.%E2%80%9D In the first two years, the borehole reference design and backfill analysis were completed and the supporting modeling of borehole temperature and fluid transport profiles were done. In the third year, some of the logistics of implementing a deep borehole waste disposal system were considered. This report describes what was learned in the third year of the study and draws some conclusions about the potential bottlenecks of system implementation.

  6. User`s Manual for the SOURCE1 and SOURCE2 Computer Codes: Models for Evaluating Low-Level Radioactive Waste Disposal Facility Source Terms (Version 2.0)

    SciTech Connect

    Icenhour, A.S.; Tharp, M.L.

    1996-08-01

    The SOURCE1 and SOURCE2 computer codes calculate source terms (i.e. radionuclide release rates) for performance assessments of low-level radioactive waste (LLW) disposal facilities. SOURCE1 is used to simulate radionuclide releases from tumulus-type facilities. SOURCE2 is used to simulate releases from silo-, well-, well-in-silo-, and trench-type disposal facilities. The SOURCE codes (a) simulate the degradation of engineered barriers and (b) provide an estimate of the source term for LLW disposal facilities. This manual summarizes the major changes that have been effected since the codes were originally developed.

  7. Sealing concepts for the Waste Isolation Pilot Plant (WIPP) site

    SciTech Connect

    Christensen, C.L.; Gulick, C.W.; Lambert, S.J.

    1982-09-01

    The Waste Isolation Pilot Plant (WIPP) facility is proposed for development in the southeast portion of the State of New Mexico. The proposed horizon is in bedded salt located approximately 2150 ft below the surface. The purpose of the WIPP is to provide an R&D facility to demonstrate the safe disposal of radioactive wastes resulting from defense activities of the United States. As such, it will include a disposal demonstration for transuranic (TRU) wastes and an experimental area to address issues associated with disposal of defense high level wastes (DHLW) in bedded salt. All DHLW used in the experiments are planned for retrieval at the termination of testing; the TRU waste can be permanently disposed of at the site after the pilot phase is complete. This report addresses only the Plugging and Sealing program, which will result in an adequate and acceptable technology for final sealing and decommissioning of the facility at the WIPP site. The actual plugging operations are intended to be conducted on a commercial industrial basis through contracts issued by the DOE. This report is one in a series that is based on a technical program of modeling, laboratory materials testing and field demonstration which will provide a defensible basis for the actual plugging operations to be conducted by the DOE for final closure of the facility.

  8. Preliminary design of a biological treatment facility for trench water from a low-level radioactive waste disposal area at West Valley, New York

    SciTech Connect

    Rosten, R.; Malkumus, D.; Sonntag, T.; Sundquist, J.

    1993-03-01

    The New York State Energy Research and Development Authority (NYSERDA) owns and manages a State-Licensed Low-Level Radioactive Waste Disposal Area (SDA) at West Valley, New York. Water has migrated into the burial trenches at the SDA and collected there, becoming contaminated with radionuclides and organic compounds. The US Environmental Protection Agency issued an order to NYSERDA to reduce the levels of water in the trenches. A treatability study of the contaminated trench water (leachate) was performed and determined the best available technology to treat the leachate and discharge the effluent. This paper describes the preliminary design of the treatment facility that incorporates the bases developed in the leachate treatability study.

  9. Standard Review Plan for the review of a license application for a low-level radioactive waste disposal facility. Revision 3

    SciTech Connect

    Not Available

    1994-04-01

    The Standard Review Plan (SRP) (NUREG-1200) provides guidance to staff reviewers in the Office of Nuclear Material Safety and Safeguards who perform safety reviews of applications to construct and operate low-level radioactive waste disposal facilities. The SRP ensures the quality and uniformity of the staff reviews and presents a well-defined base from which to evaluate proposed changes in the scope and requirements of the staff reviews. The SRP makes information about the regulatory licensing process widely available and serves to improve the understanding of the staff`s review process by interested members of the public and the industry. Each individual SRP addresses the responsibilities of persons performing the review, the matters that are reviewed, the Commission`s regulations and acceptance criteria necessary for the review, how the review is accomplished, the conclusions that are appropriate, and the implementation requirements.

  10. Recommendations to the NRC for review criteria for alternative methods of low-level radioactive waste disposal: Task 2b: Earth-mounded concrete bunkers

    SciTech Connect

    Denson, R.H.; Bennett, R.D.; Wamsley, R.M.; Bean, D.L.; Ainsworth, D.L.

    1988-01-01

    The US Army Engineers Waterways Experiment Station (WES) and US Army Engineer Division, Huntsville (HNDED) have developed general design criteria and specific design review criteria for the earth-mounded concrete bunker (EMCB) alternative method of low-level radioactive waste (LLW) disposal. An EMCB is generally described as a reinforced concrete vault placed below grade, underneath a tumulus, surrounded by filter-blanket and drainage zones. The tumulus is covered over with a low permeability cover layer and top soil with vegetation. Eight major review criteria categories have been developed ranging from the loads imposed on the EMCB structure through material quality and durability considerations. Specific design review criteria have been developed in detail for each of the eight major categories. 63 refs., 13 figs., 2 tabs.

  11. Recommendations to the NRC for review criteria for alternative methods of low-level radioactive waste disposal: Task 2a, Below-ground vaults

    SciTech Connect

    Denson, R.H.; Bennett, R.D.; Wamsley, R.M.; Bean, D.L.; Ainsworth, D.L.

    1987-12-01

    The US Army Engineer Waterways Experiment Station (WES) and the US Army Engineer Division, Huntsville (HNDED) have developed general design criteria and specific design review criteria for the below-ground vault (BGV) alternative method of low-level radioactive waste (LLW) disposal. A BGV is a reinforced concrete vault (floor, walls, and roof) placed underground below the frost line, and above the water table, surrounded by filter blanket and drainage zones and covered with a low permeability earth layer and top soil with vegetation. Eight major review criteria categories have been developed ranging from the loads imposed on the BGV structure through material quality and durability considerations. Specific design review criteria have been developed in detail for seven of the eight major categories. 59 refs., 14 figs., 2 tabs.

  12. Preliminary report on the geology and hydrology of Mortandad Canyon near Los Alamos, New Mexico, with reference to disposal of liquid low-level radioactive waste

    USGS Publications Warehouse

    Baltz, E.H.; Abrahams, J.H., Jr.; Purtyman, W.D.

    1963-01-01

    The U.S. Geological Survey, in cooperation with the U.S. Atomic Energy Commission and the Los Alamos Scientific Laboratory, selected the upper part of Mortandad Canyon near Los Alamos, New Mexico for a site for disposal of treated liquid low-level radioactive waste. This report summarizes the part of a study of the geology and hydrology that was done from October 1960 through June 1961. Additional work is being continued. Mortandad Canyon is a narrow east-southeast-trending canyon about 9? miles long that heads on the central part of the Pajarito Plateau at an altitude of about 7,340 feet. The canyon is tributary to the Rio Grande. The drainage area of the part of Mortandad Canyon that was investigated is about 2 square miles, and the total drainage area is about 4.9 square miles. The Pajarito Plateau is capped by the Bandelier Tuff of Pleistocene age. Mortandad Canyon is cut in the Bandelier, and alluvium covers the floor of the canyon to depths ranging from less than 1 foot to as much as 100 feet. The Bandelier is underlain by silt, sand, conglomerate, and interbedded basalt of the Santa Fe Group of Miocene, Pliocene, and Pleistocene(?) age. Some ground water is perched in the alluvium in the canyon; however, the top of the main aquifer is in the Santa Fe Group at a depth of about 990 feet below the canyon floor. Joints in the Bandelier Tuff probably were caused by shrinkage of the tuff during cooling. The joints range in width from hairline cracks to fissures several inches wide. Water can infiltrate along the open joints where the Bandelier is at the surface; however, soil, alluvial fill, and autochthonous clay inhibit infiltration on the tops of mesas and probably in the alluvium-floored canyons also. Thirty-three test holes, each less than 100 feet deep, were drilled in 10 lies across Mortandad Canyon from the western margin of the study area to just west of the Los Alamos-Santa Fe County line. Ten of the holes were cased for observation wells to measure

  13. Engineered soils for low-level radioactive waste disposal facilities: Effects of additives on the adsorptive behavior and hydraulic conductivity of natural soils

    SciTech Connect

    Katz, L.E.; Humphrey, D.N.; DeMascio, F.A.

    1996-12-31

    The siting of low-level radioactive waste disposal facilities requires locations having suitable soil materials beneath the proposed facility. These soils should be selected or designed to control water infiltration and ponding and enhance adsorption of radionuclides. This paper has investigated the effect of four soil additives on the hydraulic conductivity and adsorption characteristics of two natural soils, a glacial till and marine clay. The additives studied in this paper were andisol, bentonite, clinoptilolite and hematite. The results of the hydraulic conductivity testing indicated that remolding and recompacting the soils produced a more homogeneous soil having lower hydraulic conductivities. Comparison of the hydraulic conductivity and adsorptive behavior of the background soils, the additives, and mixtures of background soils and additives indicated that andisol and clinoptilolite provided the most improvement with respect to increasing adsorption capacity for iodide and strontium, respectively, with little effect on the hydraulic conductivity. The extent of adsorption and the effects of the additives on adsorption were highly pH dependent. The impact of the additives was most significant at acidic pH for both strontium and iodide adsorption because at high pH iodide adsorption was minimal for any of the materials tested and all of the background soils adsorbed a significant amount of strontium at high pH. These results suggest that engineered soils, comprised of a mixture of soil and additives, when used below a low-level radioactive waste disposal facility can enhance the ability of a site to retard off-site migration of radionuclides. 40 refs., 15 figs., 6 tabs.

  14. High-density support matrices: Key to the deep borehole disposal of spent nuclear fuel

    NASA Astrophysics Data System (ADS)

    Gibb, F. G. F.; McTaggart, N. A.; Travis, K. P.; Burley, D.; Hesketh, K. W.

    2008-03-01

    Deep (4-5 km) boreholes are emerging as a safe, secure, environmentally sound and potentially cost-effective option for disposal of high-level radioactive wastes, including plutonium. One reason this option has not been widely accepted for spent fuel is because stacking the containers in a borehole could create load stresses threatening their integrity with potential for releasing highly mobile radionuclides like 129I before the borehole is filled and sealed. This problem can be overcome by using novel high-density support matrices deployed as fine metal shot along with the containers. Temperature distributions in and around the disposal are modelled to show how decay heat from the fuel can melt the shot within weeks of disposal to give a dense liquid in which the containers are almost weightless. Finally, within a few decades, this liquid will cool and solidify, entombing the waste containers in a base metal sarcophagus sealed into the host rock.

  15. The influence of natural organic matter on radionuclide mobility under conditions relevant to cementitious disposal of radioactive wastes: A review of direct evidence

    NASA Astrophysics Data System (ADS)

    Stockdale, Anthony; Bryan, Nick D.

    2013-06-01

    A concept for the disposal of intermediate level radioactive wastes involves emplacement within a geological disposal facility, followed by backfilling of the facility with cement. When the closed facility is re-saturated with groundwater, this will create a high pH environment due to dissolution of the cement minerals. Dissolved organic matter (DOM; defined here as naturally occurring organic acids and humin) will be present in the groundwater at a concentration that reflects the host rock environment and the recharge source and pathway. Interactions between DOM and radionuclides may enhance transport away from the facility and are an important consideration in safety performance assessments. This review specifically focuses on studies of DOM-radionuclide interactions at the high pH range that is expected during a repository lifetime. Whilst the vast majority of available data cover binary (DOM-radionuclide) and batch ternary systems (mineral-radionuclide-DOM), this review also covers other potentially important areas, such as reversibility kinetics and redox processes that can be mediated by DOM.

  16. Radioactive characterization of leachates and efflorescences in the neighbouring areas of a phosphogypsum disposal site as a preliminary step before its restoration.

    PubMed

    Gázquez, M J; Mantero, J; Mosqueda, F; Bolívar, J P; García-Tenorio, R

    2014-11-01

    After the recent closure of certain phosphoric acid plants located in the South-West of Spain, it has been decided to restore a big extension (more than six hundred hectares) of salt-marshes, where some million tonnes of phosphogypsum (PG), the main by-product generated by these plants, had been disposed of. This PG is characterized by its content of high activity concentrations of several radionuclides from the uranium series, mainly (226)Ra, (210)Pb, and (210)Po and, to a lesser extent, U-isotopes. The PG disposal area can be considered as a potential source of radionuclides into their nearby environment, through the waters which percolate from them and through the efflorescences formed in their surroundings. For this reason, a detailed radioactive characterization of the mentioned waters and efflorescences has been considered essential for a proper planning of the restoration tasks to be applied in the near future in the zone. To this end, U-isotopes, (234)Th, (230)Th, (226)Ra, (210)Pb and (210)Po activity concentrations have been determined by applying both alpha-particle and gamma-ray spectrometric techniques to selected water and efflorescence aliquots collected in the area. The analysis of the obtained results has enabled to obtain information about the geochemical behaviour in the area of the different radionuclides analyzed; and the conclusion to be drawn that, in the restoration plan under preparation, both the prohibition of outflowing waters from the disposal area to the neighbouring salt-marshes, and the removal of all the efflorescences now disseminated in their surroundings are essential. PMID:25014882

  17. 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

  18. Real-Time Gamma Imaging of Technetium Transport through Natural and Engineered Porous Materials for Radioactive Waste Disposal

    PubMed Central

    2013-01-01

    We present a novel methodology for determining the transport of technetium-99m, a γ-emitting metastable isomer of 99Tc, through quartz sand and porous media relevant to the disposal of nuclear waste in a geological disposal facility (GDF). Quartz sand is utilized as a model medium, and the applicability of the methodology to determine radionuclide transport in engineered backfill cement is explored using the UK GDF candidate backfill cement, Nirex Reference Vault Backfill (NRVB), in a model system. Two-dimensional distributions in 99mTc activity were collected at millimeter-resolution using decay-corrected gamma camera images. Pulse-inputs of ∼20 MBq 99mTc were introduced into short (<10 cm) water-saturated columns at a constant flow of 0.33 mL min–1. Changes in calibrated mass distribution of 99mTc at 30 s intervals, over a period of several hours, were quantified by spatial moments analysis. Transport parameters were fitted to the experimental data using a one-dimensional convection–dispersion equation, yielding transport properties for this radionuclide in a model GDF environment. These data demonstrate that 99Tc in the pertechnetate form (Tc(VII)O4–) does not sorb to cement backfill during transport under model conditions, resulting in closely conservative transport behavior. This methodology represents a quantitative development of radiotracer imaging and offers the opportunity to conveniently and rapidly characterize transport of gamma-emitting isotopes in opaque media, relevant to the geological disposal of nuclear waste and potentially to a wide variety of other subsurface environments. PMID:24147650

  19. Radioactive Wastes.

    PubMed

    Choudri, B S; Baawain, Mahad

    2016-10-01

    Papers reviewed herein present a general overview of radioactive waste activities around the world in 2015. These include safety assessments, decommission and decontamination of nuclear facilities, fusion facilities, transportation and management solutions for the final disposal of low and high level radioactive wastes (LLW and HLW), interim storage and final disposal options for spent fuel (SF), and tritiated wastes, with a focus on environmental impacts due to the mobility of radionuclides in water, soil and ecosystem alongwith other progress made in the management of radioactive wastes. PMID:27620100

  20. Radioactive Wastes.

    PubMed

    Choudri, B S; Baawain, Mahad

    2015-10-01

    Papers reviewed herein present a general overview of radioactive waste activities around the world in 2014. These include safety assessments, decommission and decontamination of nuclear facilities, fusion facilities, transportation and management solutions for the final disposal of low and high level radioactive wastes (LLW and HLW), interim storage and final disposal options for spent fuel (SF), and tritiated wastes, with a focus on environmental impacts due to the mobility of radionuclides in water, soil and ecosystem alongwith other progress made in the management of radioactive wastes. PMID:26420096

  1. Disposal concepts and characteristics of existing and potential low-waste repositories - 9076

    SciTech Connect

    Johnson, Peter J; Zarling, John C

    2009-01-01

    The closure of the Barnwell low-level waste (LLW) disposal facility to non-Atlantic Compact users poses significant problems for organizations seeking to remove waste material from public circulation. Beta-gamma sources such as {sup 137}Cs and {sup 90}Sr in particular create problems because in 36 states no path forward exists for disposal. Furthermore, several other countries are considering disposition of sealed sources in a variety of facilities. Like much of the United States, many of these countries currently have no means of disposal. Consequently, there is a greater tendency for sources to be misplaced or stored in insufficient facilities, resulting in an increased likelihood of unwitting exposure of nearby people to radioactive materials. This paper provides an overview of the various disposal concepts that have been employed or attempted in the United States. From these concepts, a general overview of characteristics necessary for long-term disposal is synthesized.

  2. Studies on important radionuclides for the safety of a radioactive waste disposal site: Correlation between easily measurable gamma emitters and long-lived radionuclides

    SciTech Connect

    Raymond, A.; Lagarde, B.; Pitiot, A.

    1996-08-01

    To comply with the regulations laid down by the French safety authorities for a national surface disposal site, one must obtain a good evaluation of the activity of the long-lived nuclides in each individual package. Because this cannot be done on a routine basis by direct nondestructive measurements, experiments are being conducted in France to calculate the activity of long-lived nuclides from the measured activity of key nuclides ({sup 60}Co and {sup 137}Cs). This is achieved through the use of scaling factors and correlation functions that are calculated from the analysis of a limited number of representative waste samples. The first results obtained for some typical French pressurized water reactor radioactive wastes, including ion-exchange resins, evaporator concentrates, and filter cartridges, are presented. Significant correlations are observed for the {sup 63}Ni/{sup 60}Co and {sup 94}Nb/{sup 60}Co nuclide pairs, while {sup 14}C does not seem to correlate with {sup 60}Co. A good correlation between {sup 137}Cs and {sup 90}Sr is established for resins, while in the case of filters, only a tendency to correlation appears. This evaluation work is only at a preliminary stage, and much improvement of the results presented here is expected from research programs being carried out in this field by Electricite de France, commissariat a l`Energie Atomique, and the French National Agency for Radioactive Waste Management in cooperation with the Commission of the European Communities.

  3. Geologic observations at the 2800-meter radioactive waste disposal site and associated deepwater dumpsite 106 (DWD-106) in the Atlantic Ocean. (Revised). Final report

    SciTech Connect

    Rawson, M.D.; Ryan, W.B.F.

    1983-09-01

    During 1975 and 1976 a total of eight manned submersible dives with DSRV ALVIN were carried out in a relatively small region of the Atlantic 2800m radioactive waste dumpsite and were centered at 38 degrees 30'N and 72 degrees 09'W. Six other dives were distributed through the northern part of Deepwater Dumpsite 106 (DWD-106) near the boundary of the continental rise/continental slope. One of the primary purposes of these dives was to observe the geological conditions in this disposal region slightly south of the Hudson submarine Canyon. The lower continental slope was found to be incised by submarine canyons debouching into the northern side of DWD-106. The upper continental rise was incised by narrow meandering channels. One of these channels passed through the radioactive waste dumpsite and was surveyed in detail. On the upper continental rise the local terrain was relatively flat but studded with numerous tracks, trails, holes, and mounds of biological orgin. The sediment carpet was composed of a grapy silty-clay. Detailed mineralogical analysis was performed.

  4. Corrective Action Decision Document/Closure Report for Corrective Action Unit 545: Dumps, Waste Disposal Sites, and Buried Radioactive Materials Nevada Test Site, Nevada, Revision 0

    SciTech Connect

    Alfred Wickline

    2008-04-01

    This Corrective Action Decision Document (CADD)/Closure Report (CR) has been prepared for Corrective Action Unit (CAU) 545, Dumps, Waste Disposal Sites, and Buried Radioactive Materials, in Areas 2, 3, 9, and 20 of the Nevada Test Site, Nevada, in accordance with the Federal Facility Agreement and Consent Order that was agreed to by the State of Nevada; U.S. Department of Energy (DOE), Environmental Management; U.S. Department of Defense; and DOE, Legacy Management (1996, as amended February 2008). Corrective Action Unit 545 is comprised of the following eight Corrective Action Sites (CASs): • 02-09-01, Mud Disposal Area • 03-08-03, Mud Disposal Site • 03-17-01, Waste Consolidation Site 3B • 03-23-02, Waste Disposal Site • 03-23-05, Europium Disposal Site • 03-99-14, Radioactive Material Disposal Area • 09-23-02, U-9y Drilling Mud Disposal Crater • 20-19-01, Waste Disposal Site While all eight CASs are addressed in this CADD/CR, sufficient information was available for the following three CASs; therefore, a field investigation was not conducted at these sites: • For CAS 03-08-03, though the potential for subsidence of the craters was judged to be extremely unlikely, the data quality objective (DQO) meeting participants agreed that sufficient information existed about disposal and releases at the site and that a corrective action of close in place with a use restriction is recommended. Sampling in the craters was not considered necessary. • For CAS 03-23-02, there were no potential releases of hazardous or radioactive contaminants identified. Therefore, the Corrective Action Investigation Plan for CAU 545 concluded that: “Sufficient information exists to conclude that this CAS does not exist as originally identified. Therefore, there is no environmental concern associated with CAS 03-23-02.” This CAS is closed with no further action. • For CAS 03-23-05, existing information about the two buried sources and lead pig was considered to be

  5. Security seal

    DOEpatents

    Gobeli, Garth W.

    1985-01-01

    Security for a package or verifying seal in plastic material is provided by a print seal with unique thermally produced imprints in the plastic. If tampering is attempted, the material is irreparably damaged and thus detectable. The pattern of the imprints, similar to "fingerprints" are recorded as a positive identification for the seal, and corresponding recordings made to allow comparison. The integrity of the seal is proved by the comparison of imprint identification records made by laser beam projection.

  6. Features, events, processes, and safety factor analysis applied to a near-surface low-level radioactive waste disposal facility

    SciTech Connect

    Stephens, M.E.; Dolinar, G.M.; Lange, B.A.

    1995-12-31

    An analysis of features, events, processes (FEPs) and other safety factors was applied to AECL`s proposed IRUS (Intrusion Resistant Underground Structure) near-surface LLRW disposal facility. The FEP analysis process which had been developed for and applied to high-level and transuranic disposal concepts was adapted for application to a low-level facility for which significant efforts in developing a safety case had already been made. The starting point for this process was a series of meetings of the project team to identify and briefly describe FEPs or safety factors which they thought should be considered. At this early stage participants were specifically asked not to screen ideas. This initial list was supplemented by selecting FEPs documented in other programs and comments received from an initial regulatory review. The entire list was then sorted by topic and common issues were grouped, and issues were classified in three priority categories and assigned to individuals for resolution. In this paper, the issue identification and resolution process will be described, from the initial description of an issue to its resolution and inclusion in the various levels of the safety case documentation.

  7. Geologic and hydrologic characterization and evaluation of the Basin and Range Province relative to the disposal of high-level radioactive waste. Part II. Geologic and hydrologic characterization

    SciTech Connect

    Sargent, K.A.; Bedinger, M.S.

    1985-12-31

    The geology and hydrology of the Basin and Range Province of the western conterminous United States are characterized in a series of data sets depicted in maps compiled for evaluation of prospective areas for further study of geohydrologic environments for isolation of high-level radioactive waste. The data sets include: (1) average precipitation and evaporation; (2) surface distribution of selected rock types; (3) tectonic conditions; and (4) surface- and ground-water hydrology and Pleistocene lakes and marshes. Rocks mapped for consideration as potential host media for the isolation of high-level radioactive waste are widespread and include argillaceous rocks, granitic rocks, tuffaceous rocks, mafic extrusive rocks, evaporites, and laharic breccias. The unsaturated zone, where probably as thick as 150 meters (500 feet), was mapped for consideration as an environment for isolation of high-level waste. Unsaturated rocks of various lithologic types are widespread in the Province. Tectonic stability in the Quaternary Period is considered the key to assessing the probability of future tectonism with regard to high-level radioactive waste disposal. Tectonic conditions are characterized on the basis of the seismic record, heat-flow measurements, the occurrence of Quaternary faults, vertical crustal movement, and volcanic features. Tectonic activity, as indicated by seismicity, is greatest in areas bordering the western margin of the Province in Nevada and southern California, the eastern margin of the Province bordering the Wasatch Mountains in Utah and in parts of the Rio Grande valley. Late Cenozoic volcanic activity is widespread, being greatest bordering the Sierra Nevada in California and Oregon, and bordering the Wasatch Mountains in southern Utah and Idaho. 43 refs., 22 figs.

  8. Milestones for disposal of radioactive waste at the Waste Isolation Pilot Plant (WIPP) in the United States

    SciTech Connect

    RECHARD,ROBERT P.

    2000-03-01

    The opening of the Waste Isolation Pilot Plant on March 26, 1999, was the culmination of a regulatory assessment process that had taken 25 years. National policy issues, negotiated agreements, and court settlements during the first 15 years of the project had a strong influence on the amount and type of scientific data collected up to this point. Assessment activities before the mid 1980s were undertaken primarily (1) to satisfy needs for environmental impact statements, (2) to satisfy negotiated agreements with the State of New Mexico, or (3) to develop general understanding of selected natural phenomena associated with nuclear waste disposal. In the last 10 years, federal compliance policy and actual regulations were sketched out, and continued to evolve until 1996. During this period, stochastic simulations were introduced as a tool for the assessment of the WIPP's performance, and four preliminary performance assessments, one compliance performance assessment, and one verification performance assessment were performed.

  9. Milestones for disposal of radioactive waste at the Waste Isolation Pilot Plant (WIPP) in the United States

    SciTech Connect

    Rechard, R.P.

    1998-04-01

    Since its identification as a potential deep geologic repository in about 1973, the regulatory assessment process for the Waste Isolation Pilot Plant (WIPP) in New Mexico has developed over the past 25 years. National policy issues, negotiated agreements, and court settlements over the first half of the project had a strong influence on the amount and type of scientific data collected. Assessments and studies before the mid 1980s were undertaken primarily (1) to satisfy needs for environmental impact statements, (2) to develop general understanding of selected natural phenomena associated with nuclear waste disposal, or (3) to satisfy negotiated agreements with the State of New Mexico. In the last third of the project, federal compliance policy and actual regulations were sketched out, but continued to evolve until 1996. During this eight-year period, four preliminary performance assessments, one compliance performance assessment, and one verification performance assessment were performed.

  10. Evaluation of a performance assessment methodology for low-level radioactive waste disposal facilities: Validation needs. Volume 2

    SciTech Connect

    Kozak, M.W.; Olague, N.E.

    1995-02-01

    In this report, concepts on how validation fits into the scheme of developing confidence in performance assessments are introduced. A general framework for validation and confidence building in regulatory decision making is provided. It is found that traditional validation studies have a very limited role in developing site-specific confidence in performance assessments. Indeed, validation studies are shown to have a role only in the context that their results can narrow the scope of initial investigations that should be considered in a performance assessment. In addition, validation needs for performance assessment of low-level waste disposal facilities are discussed, and potential approaches to address those needs are suggested. These areas of topical research are ranked in order of importance based on relevance to a performance assessment and likelihood of success.

  11. Approaches to long-term performance assessment of deep underground disposal of radioactive wastes: A European perspective

    SciTech Connect

    Sumerling, T.J.; Read, D.

    1993-12-31

    The aim of long-term performance assessment (PA) is generally to develop confidence that the disposal system will perform within certain bounds and give rise to acceptably low impacts or risks. The PA procedure must be able to deal with: (1) uncertainty due to incomplete understanding of the relevant processes; (2) uncertainty due to limited sampling of the structures and characteristics of the system and especially the geological media; (3) uncertainty about future conditions and processes leading to changes in the engineered barriers and natural environment that may affect radionuclide release, transport and exposure pathways. A number of approaches have been taken to solving the problem of how to deal with such uncertainties. The differences in approach may be due to the stage of project development, differences in national regulatory guidance and the different roles of the implementor and the regulator. This paper examines the roles of the implementor and regulator and discusses possible approaches appropriate to both points of view.

  12. Turbomachine Sealing

    NASA Technical Reports Server (NTRS)

    Hendricks, Robert C.

    1996-01-01

    Designers and customers are demanding higher performance turbomachine systems that have long life between overhauls and satisfy the more restrictive environmental constraints. This overview provides sources of design data, numerical, and experimental results along with selected new seal configurations and static sealing challenges such as in the combustors. The following categories are presented: (1) Seal Rotordynamic Data Base (experimental analytical program at Texas A&M); (2) Secondary Flow Interactions (validation studies at CFDRC, Huntsville AL); (3) Contact Sealing (selected types with finger seal model); and (4) Environmental Constraints (emphasis on combustors).

  13. Bellows sealed plug valve

    DOEpatents

    Dukas, Jr., Stephen J.

    1990-01-01

    A bellows sealed plug valve includes a valve body having an inlet passage and an outlet passage, a valve chamber between the inlet and outlet passages. A valve plug has substantially the same shape as the valve chamber and is rotatably disposed therein. A shaft is movable linearly in response to a signal from a valve actuator. A bellows is sealingly disposed between the valve chamber and the valve actuator and means are located between the bellows and the valve plug for converting linear movement of the shaft connected to the valve actuator to rotational movement of the plug. Various means are disclosed including helical thread mechanism, clevis mechanism and rack and pinion mechanism, all for converting linear motion to rotational motion.

  14. Mechanical environmental transport of actinides and ¹³⁷Cs from an arid radioactive waste disposal site

    DOE PAGESBeta

    Snow, Mathew S.; Clark, Sue B.; Morrison, Samuel S.; Watrous, Matthew G.; Olson, John E.; Snyder, Darin C.

    2015-10-01

    Particulate transport represents an important mechanism for actinides and fission products at the Earth's surface; soil samples taken in the early 1970's near the Subsurface Disposal Area (SDA) at Idaho National Laboratory (INL) provide a case study for examining the mechanisms and characteristics of actinide transport under arid conditions. Transuranic waste was disposed via shallow land burial at the SDA until shortly after a flooding event that occurred in 1969. In this study we analyze soils collected in the early 1970's for ¹³⁷Cs, ²⁴¹Am, and Pu using a combination of radiometric and mass spectrometric techniques. Two distinct ²⁴⁰Pu/²³⁹Pu isotopic ratiosmore » are observed for contamination from the SDA, with values ranging from at least 0.059 to 0.069. ²⁴¹Am concentrations are observed to increase only slightly in 0-4 cm soils over the ~40 year period since soil sampling, contrary to Markham's previous hypothesis that ²⁴¹Pu is principally associated with the 0-4 cm soil fractions (Markham 1978). The lack of statistical difference in ²⁴¹Am/²³⁹⁺²⁴⁰Pu ratios with depth suggests mechanical transport and mixing discrete contaminated particles under arid conditions. Occasional samples beyond the northeastern corner are observed to contain anomalously high Pu concentrations with corresponding low ²⁴⁰Pu/²³⁹Pu atoms ratios, suggesting the occurrence of "hot particles;" application of a background Pu subtraction results in calculated Pu atom ratios for the "hot particles" which are statistically similar to those observed in the northeastern corner. Taken together, our data suggests that flooding resulted in mechanical transport of contaminated particles into the area between the SDA and the flood containment dike in the northeastern corner, following which subsequent contamination spreading resulted from wind transport of discrete particles.« less

  15. Mechanical environmental transport of actinides and ¹³⁷Cs from an arid radioactive waste disposal site

    SciTech Connect

    Snow, Mathew S.; Clark, Sue B.; Morrison, Samuel S.; Watrous, Matthew G.; Olson, John E.; Snyder, Darin C.

    2015-10-01

    Particulate transport represents an important mechanism for actinides and fission products at the Earth's surface; soil samples taken in the early 1970's near the Subsurface Disposal Area (SDA) at Idaho National Laboratory (INL) provide a case study for examining the mechanisms and characteristics of actinide transport under arid conditions. Transuranic waste was disposed via shallow land burial at the SDA until shortly after a flooding event that occurred in 1969. In this study we analyze soils collected in the early 1970's for ¹³⁷Cs, ²⁴¹Am, and Pu using a combination of radiometric and mass spectrometric techniques. Two distinct ²⁴⁰Pu/²³⁹Pu isotopic ratios are observed for contamination from the SDA, with values ranging from at least 0.059 to 0.069. ²⁴¹Am concentrations are observed to increase only slightly in 0-4 cm soils over the ~40 year period since soil sampling, contrary to Markham's previous hypothesis that ²⁴¹Pu is principally associated with the 0-4 cm soil fractions (Markham 1978). The lack of statistical difference in ²⁴¹Am/²³⁹⁺²⁴⁰Pu ratios with depth suggests mechanical transport and mixing discrete contaminated particles under arid conditions. Occasional samples beyond the northeastern corner are observed to contain anomalously high Pu concentrations with corresponding low ²⁴⁰Pu/²³⁹Pu atoms ratios, suggesting the occurrence of "hot particles;" application of a background Pu subtraction results in calculated Pu atom ratios for the "hot particles" which are statistically similar to those observed in the northeastern corner. Taken together, our data suggests that flooding resulted in mechanical transport of contaminated particles into the area between the SDA and the flood containment dike in the northeastern corner, following which subsequent contamination spreading resulted from wind transport of discrete particles.

  16. 10 CFR 61.50 - Disposal site suitability requirements for land disposal.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 2 2013-01-01 2013-01-01 false Disposal site suitability requirements for land disposal. 61.50 Section 61.50 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSING REQUIREMENTS FOR LAND DISPOSAL OF RADIOACTIVE WASTE Technical Requirements for Land Disposal Facilities § 61.50 Disposal site suitability requirements for land disposal....

  17. 10 CFR 61.50 - Disposal site suitability requirements for land disposal.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 2 2011-01-01 2011-01-01 false Disposal site suitability requirements for land disposal. 61.50 Section 61.50 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSING REQUIREMENTS FOR LAND DISPOSAL OF RADIOACTIVE WASTE Technical Requirements for Land Disposal Facilities § 61.50 Disposal site suitability requirements for land disposal....

  18. 10 CFR 61.50 - Disposal site suitability requirements for land disposal.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 2 2014-01-01 2014-01-01 false Disposal site suitability requirements for land disposal. 61.50 Section 61.50 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSING REQUIREMENTS FOR LAND DISPOSAL OF RADIOACTIVE WASTE Technical Requirements for Land Disposal Facilities § 61.50 Disposal site suitability requirements for land disposal....

  19. Spanish LLW and MLW disposal: durability of cemented materials in (Na, K)Cl simulated radioactive liquid waste.

    PubMed

    Goñi, S; Guerrero, A; Hernández, M S

    2001-01-01

    The microstructural stability or durability of a specific backfilling pozzolanic-cement mortar, which is employed in Spain, in concrete containers for the storage of low level liquid wastes (LLW) and medium level liquid wastes (MLW), has been studied by means of the Koch-Steinegger test at the temperatures of 20 and 40 degrees C during a period of 365 days. Mortar samples were immersed in salt solutions of 3.46 M NaCl and 3.46 M KCl to simulate the salinity of some radioactive liquid waste matrices. The resistance of the mortar to the saline solution attack is evaluated by the development of the relative flexural strength. The changes of the microstructure were followed by mercury intrusion porosimetry (MIP), scanning electron microscopy (SEM) and X-ray diffraction (XRD). Pore solution was extracted and analyzed at different periods of time to know the possible diffusion of sodium, chloride and potassium inside the microstructure. PMID:11150135

  20. Floristic composition and plant succession on near-surface radioactive-waste-disposal facilities in the Los Alamos National Laboratory

    SciTech Connect

    Tierney, G.D.; Foxx, T.S.

    1982-03-01

    Since 1946, low-level radioactive waste has been buried in shallow landfills within the confines of the Los Alamos National Laboratory. Five of these sites were studied for plant composition and successional patterns by reconnaissance and vegetation mapping. The data show a slow rate of recovery for all sites, regardless of age, in both the pinon-juniper and ponderosa pine communities. The sites are not comparable in succession or composition because of location and previous land use. The two oldest sites have the highest species diversity and the only mature trees. All sites allowed to revegetate naturally tend to be colonized by the same species that originally surrounded the sites. Sites on historic fields are colonized by the old field flora, whereas those in areas disturbed only by grazing are revegetated by the local native flora.

  1. Hydrology and water-quality at the Weldon Spring radioactive waste-disposal sites, St Charles County, Missouri

    USGS Publications Warehouse

    Kleeschulte, M.J.; Emmett, L.F.

    1987-01-01

    Water samples from five monitoring wells adjacent to raffinate pits storing low-level radioactive waste contained concentrations of nitrate as nitrogen ranging from 53 to 990 milligrams per liter. Most samples also had maximum concentrations of calcium (900 milligrams per liter), sodium (340 milligrams per liter), sulfate (320 milligrams per liter), lithium (1,700 micrograms), strontium (1,900 micrograms per liter), and uranium (86 micrograms per liter). The raffinate pits also had large concentrations of these constituents. A water balance made on the raffinate pits indicated a 0.04 to 0.08 inch per day decrease in the water level that cannot be attributed to meterological conditions. These data and seismically-detected areas of saturated overburden beneath one raffinate pit and possibly adjacent to three other pits indicate leakage from the pits. (USGS)

  2. Turbine engine interstage seal

    SciTech Connect

    Clevenger, L.L.

    1993-08-10

    A seal structure is described for a turbine engine, the turbine engine including a housing surrounding a centrifugal compressor having a rotor, and a radial inflow turbine including a turbine rotor, the compressor rotor and the turbine rotor being disposed in back-to-back relation, the turbine rotor being drivingly connected with the compressor rotor and axially spaced therefrom to define an annular gap there between, the gap radially bounded at its outer periphery by the housing and at its inner periphery by an annular surface intermediate the compressor rotor and the turbine rotor an annular sealing member disposed in the gap to control air flow from the compressor toward the turbine; the annular sealing member the first axial direction, and a third annular wall portion joining with the second annular wall portion and extending inward therefrom towards the surface intermediate the compressor rotor and the turbine rotor, and biasing means cooperating with the housing for urging the seal structure toward the turbine rotor.

  3. Potential migration of buoyant LNAPL from intermediate level waste (ILW) emplaced in a geological disposal facility (GDF) for U.K. radioactive waste.

    PubMed

    Benbow, Steven J; Rivett, Michael O; Chittenden, Neil; Herbert, Alan W; Watson, Sarah; Williams, Steve J; Norris, Simon

    2014-10-15

    A safety case for the disposal of Intermediate Level (radioactive) Waste (ILW) in a deep geological disposal facility (GDF) requires consideration of the potential for waste-derived light non-aqueous phase liquid (LNAPL) to migrate under positive buoyancy from disposed waste packages. Were entrainment of waste-derived radionuclides in LNAPL to occur, such migration could result in a shorter overall travel time to environmental or human receptors than radionuclide migration solely associated with the movement of groundwater. This paper provides a contribution to the assessment of this issue through multiphase-flow numerical modelling underpinned by a review of the UK's ILW inventory and literature to define the nature of the associated ILW LNAPL source term. Examination has been at the waste package-local GDF environment scale to determine whether proposed disposal of ILW would lead to significant likelihood of LNAPL migration, both from waste packages and from a GDF vault into the local host rock. Our review and numerical modelling support the proposition that the release of a discrete free phase LNAPL from ILW would not present a significant challenge to the safety case even with conservative approximations. 'As-disposed' LNAPL emplaced with the waste is not expected to pose a significant issue. 'Secondary LNAPL' generated in situ within the disposed ILW, arising from the decomposition of plastics, in particular PVC (polyvinyl chloride), could form the predominant LNAPL source term. Released high molecular weight phthalate plasticizers are judged to be the primary LNAPL potentially generated. These are expected to have low buoyancy-based mobility due to their very low density contrast with water and high viscosity. Due to the inherent uncertainties, significant conservatisms were adopted within the numerical modelling approach, including: the simulation of a deliberately high organic material--PVC content wastestream (2D03) within an annular grouted waste package

  4. Corrosion resistant storage container for radioactive material

    DOEpatents

    Schweitzer, D.G.; Davis, M.S.

    1984-08-30

    A corrosion resistant long-term storage container for isolating high-level radioactive waste material in a repository is claimed. The container is formed of a plurality of sealed corrosion resistant canisters of different relative sizes, with the smaller canisters housed within the larger canisters, and with spacer means disposed between juxtaposed pairs of canisters to maintain a predetermined spacing between each of the canisters. The combination of the plural surfaces of the canisters and the associated spacer means is effective to make the container capable of resisting corrosion, and thereby of preventing waste material from leaking from the innermost canister into the ambient atmosphere.

  5. Corrosion resistant storage container for radioactive material

    DOEpatents

    Schweitzer, Donald G.; Davis, Mary S.

    1990-01-01

    A corrosion resistant long-term storage container for isolating radioactive waste material in a repository. The container is formed of a plurality of sealed corrosion resistant canisters of different relative sizes, with the smaller canisters housed within the larger canisters, and with spacer means disposed between judxtaposed pairs of canisters to maintain a predetermined spacing between each of the canisters. The combination of the plural surfaces of the canisters and the associated spacer means is effective to make the container capable of resisting corrosion, and thereby of preventing waste material from leaking from the innermost canister into the ambient atmosphere.

  6. Status of the Oak Ridge National Laboratory new hydrofracture facility: Implications for the disposal of liquid low-level radioactive wastes by underground injection

    SciTech Connect

    Haase, C.S.; Stow, S.H.

    1987-01-01

    From 1982 to 1984, Oak Ridge National Laboratory (ORNL) disposed of approximately 2.8 x 10/sup 16/ Bq (7.5 x 10/sup 5/ Ci) of liquid low-level radioactive wastes by underground injection at its new hydrofracture facility. This paper summarizes the regulatory and operational status of that ORNL facility and discusses its future outlook. Operational developments and regulatory changes that have raised major questions about the continued operation of the new hydrofracture facility include: (1) significant /sup 90/Sr contamination of some groundwater in the injection formation; (2) questions about the design of the injection well, completed prior to the application of the underground injection control (UIC) regulations to the ORNL facility; (3) questions about the integrity of the reconfigured injection well put into service following the loss of the initial injection well; and (4) implementation of UIC regulations. Ultimately, consideration of the regulatory and operational factors led to the decision in early 1986 not to proceed with a UIC permit application for the ORNL facility. Subsequent to the decision not to proceed with a UIC permit application, closure activities were initiated for the ORNL hydrofracture facility. Closure of the facility will occur under both state of Tennessee and federal UIC regulations. The facility also falls under the provisions of part 3004(u) of the Resource Conservation and Recovery Act pertaining to corrective actions. Nationally, there is an uncertain outlook for the disposal of wastes by underground injection. All wells used for the injection of hazardous wastes (Class I wells) are being reviewed. 8 refs., 4 figs., 2 tabs.

  7. Asphalt emulsion sealing of uranium mill tailings. 1979 annual report

    SciTech Connect

    Hartley, J.N.; Koehmstedt, P.L.; Esterl, D.J.; Freeman, H.D.

    1980-06-01

    Uranium mill tailings are a source of low-level radiation and radioactive materials that may be released into the environment. Stabilization or disposal of these tailings in a safe and environmentally sound way is necessary to minimize radon exhalation and other radioactive releases. One of the most promising concepts for stabilizing uranium tailings is being investigated at the Pacific Northwest Laboratory: the use of asphalt emulsion to contain radon and other potentially hazardous materials in uranium tailings. Results of these studies indicate that radon flux from uranium tailings can be reduced by greater than 99% by covering the tailings with an asphalt emulsion that is poured on or sprayed on (3.0 to 7.0 mm thick), or mixed with some of the tailings and compacted to form an admixture seal (2.5 to 15.2 cm) containing 18 wt % residual asphalt.

  8. Sealed head access area enclosure

    DOEpatents

    Golden, Martin P.; Govi, Aldo R.

    1978-01-01

    A liquid-metal-cooled fast breeder power reactor is provided with a sealed head access area enclosure disposed above the reactor vessel head consisting of a plurality of prefabricated structural panels including a center panel removably sealed into position with inflatable seals, and outer panels sealed into position with semipermanent sealant joints. The sealant joints are located in the joint between the edge of the panels and the reactor containment structure and include from bottom to top an inverted U-shaped strip, a lower layer of a room temperature vulcanizing material, a separator strip defining a test space therewithin, and an upper layer of a room temperature vulcanizing material. The test space is tapped by a normally plugged passage extending to the top of the enclosure for testing the seal or introducing a buffer gas thereinto.

  9. Aerodynamic seals for rotary machine

    DOEpatents

    Bidkar, Rahul Anil; Cirri, Massimiliano; Thatte, Azam Mihir; Williams, John Robert

    2016-02-09

    An aerodynamic seal assembly for a rotary machine includes multiple sealing device segments disposed circumferentially intermediate to a stationary housing and a rotor. Each of the segments includes a shoe plate with a forward-shoe section and an aft-shoe section having multiple labyrinth teeth therebetween facing the rotor. The sealing device segment also includes multiple flexures connected to the shoe plate and to a top interface element, wherein the multiple flexures are configured to allow the high pressure fluid to occupy a forward cavity and the low pressure fluid to occupy an aft cavity. Further, the sealing device segments include a secondary seal attached to the top interface element at one first end and positioned about the flexures and the shoe plate at one second end.

  10. Characterising and modelling the excavation damaged zone (EDZ) in crystalline rock in the context of radioactive waste disposal

    SciTech Connect

    Hudson, J.A.; Backstrom, A.; Rutqvist, J.; Jing, L.; Backers, T.; Chijimatsu, M.; Christiansson, R.; Feng, X.-T.; Kobayashi, A.; Koyama, T.; Lee, H.-S.; Neretnieks, I.; Pan, P.Z.; Rinne, M.; Shen, B.-T.

    2008-10-01

    This paper describes current knowledge about the nature of and potential for thermo-hydro-mechanical-chemical modelling of the Excavation Damaged Zone (EDZ) around the excavations for an underground radioactive waste repository. In the first part of the paper, the disturbances associated with excavation are explained, together with reviews of Workshops that have been held on the subject. In the second part of the paper, the results of a DECOVALEX research programme on modelling the EDZ are presented. Four research teams used four different models to simulate the complete stress-strain curve for Avro granite from the Swedish Aespoe Hard Rock Laboratory. Subsequent research extended the work to computer simulation of the evolution of the repository using a 'wall block model' and a 'near-field model'. This included assessing the evolution of stress, failure and permeability and time dependent effects during repository evolution. As discussed, all the computer models are well suited to sensitivity studies for evaluating the influence of their respective supporting parameters on the complete stress-strain curve for rock and for modelling the EDZ.

  11. Review of potential host rocks for radioactive waste disposal in the southeast United States-Southern Piedmont subregion

    SciTech Connect

    Not Available

    1980-10-01

    A literature study was conducted on the geology of the Southern Piedmont province in the states of Maryland, Virginia, North Carolina, South Carolina, and Georgia. The purpose was to identify geologic areas potentially suitable for containment of a repository for the long-term isolation of solidified radioactive waste. The crystalline rocks of the Southern Piedmont province range in age from Precambrian to Paleozoic, and are predominantly slates, phyllites, argillites, schists, metavolcanics, gneisses, gabbros, and granites. These rock units were classified as either favorable, potentially favorable, or unfavorable as potential study areas based on an evaluation of the geologic, hydrologic, and geotechnical characteristics. No socio-economic factors were considered. Rocks subjected to multiple periods of deformation and metamorphism, or described as highly fractured, or of limited areal extent were generally ranked as unfavorable. Potentially favorable rocks are primarily the high-grade metamorphic gneisses and granites. Sixteen areas were classified as being favorable for additional study. These areas are primarily large igneous granite plutons as follows: the Petersburg granite in Virginia; the Rolesville-Castallia, Churchland, and Landis plutons in North Carolina; the Liberty Hill, Winnsboro, and Ogden plutons in South Carolina; and the Siloam, Elberton, and six unnamed granite plutons in Georgia.

  12. Survey of the degradation modes of candidate materials for high-level radioactive waste disposal containers. Final report

    SciTech Connect

    Vinson, D.W.; Bullen, D.B.

    1995-09-22

    One of the most significant factors impacting the performance of waste package container materials under repository relevant conditions is the thermal environment. This environment will be affected by the areal power density of the repository, which is dictated by facility design, and the dominant heat transfer mechanism at the site. The near-field environment will evolve as radioactive decay decreases the thermal output of each waste package. Recent calculations (Buscheck and Nitao, 1994) have addressed the importance of thermal loading conditions on waste package performance at the Yucca Mountain site. If a relatively low repository thermal loading design is employed, the temperature and relative humidity near the waste package may significantly affect the degradation of corrosion allowance barriers due to moist air oxidation and radiolytically enhanced corrosion. The purpose this report is to present a literature review of the potential degradation modes for moderately corrosion resistant nickel copper and nickel based candidate materials that may be applicable as alternate barriers for the ACD systems in the Yucca Mountain environment. This report presents a review of the corrosion of nickel-copper alloys, summaries of experimental evaluations of oxidation and atmospheric corrosion in nickel-copper alloys, views of experimental studies of aqueous corrosion in nickel copper alloys, a brief review of galvanic corrosion effects and a summary of stress corrosion cracking in these alloys.

  13. Ground-water flow near two radioactive-waste-disposal areas at the Western New York Nuclear Service Center, Cattaraugus County, New York; results of flow simulation

    USGS Publications Warehouse

    Bergeron, M.P.; Bugliosi, E.F.

    1988-01-01

    Two adjacent burial areas were excavated in a clay-rich till at a radioactive waste disposal site near West Valley in Cattaraugus County, N.Y.: (1) which contains mainly low-level radioactive wastes generated onsite by a nuclear fuel reprocessing plant, has been in operation since 1966; and (2) which contains commercial low-level radioactive wastes, was operated during 1963-75. Groundwater below the upper 3 meters of till generally moves downward through a 20- to 30-meter thick sequence of tills underlain by lacustrine and kame-delta deposits of fine sand and silt. Groundwater in the weathered, upper 3 meters of till can move laterally for several meters before either moving downward into the kame-delta deposits or discharging to the land surface. A two-dimensional finite-element model that simulates two vertical sections was used to evaluate hydrologic factors that control groundwater flow in the till. Conditions observed during March 1983 were reproduced accurately in steady-state simulations that used four isotropic units of differing hydraulic conductivity to represent two fractured and weathered till units near land surfaces, an intermediate group of isolated till zones that contain significant amounts of fine sand and silt, and a sequence of till units at depths that have been consolidated by overburden pressure. Recharge rates used in the best-fit simulation ranged from 1.4 cm/yr along smooth, sloping or compacted surfaces to 3.8 cm/yr near swampy areas. Values of hydraulic conductivity and infiltration used in the calibrated best-fit model were nearly identical to values used in a previous model analysis of the nearby commercial-waste burial area. Results of the model simulations of a burial pit assumed to be filled with water indicate that water near the bottom of the burial pit would migrate laterally in the shallow, weathered till for 5 to 6 meters before moving downward into the unweathered till, and water near the top of the pit would move laterally

  14. The use of protective barriers to deter inadvertent human intrusion into a mined geologic facility for the disposal of radioactive waste: A review of previous investigations and potential concepts

    SciTech Connect

    Tolan, T.L.

    1993-06-01

    Sandia National Laboratories is evaluating the feasibility of developing protective barrier system for the Waste Isolation Pilot Plant (WIPP) to thwart inadvertent human intrusion into this radioactive-waste disposal system for a period of 9,900 years after assumed loss of active institutional controls. The protective barrier system would be part of a series of enduring passive institutional controls whose long-term function will be to reduce the likelihood of inadvertent human activities (e.g., exploratory drilling for resources) that could disrupt the WIPP disposal system.

  15. Comparing risks from low-level radioactive waste disposal on land and in the ocean: A review of agreements/statutes, scenarios, processing/packaging/disposal technologies, models, and decision analysis methods

    SciTech Connect

    Moskowitz, P.D.; Kalb, P.D.; Morris, S.C.; Rowe, M.D. ); Marietta, M. ); Anspaugh, L; McKone, T. )

    1989-10-01

    This report gives background information on: The history of LLW disposal in the US; agreements, statutes and regulations for the disposal of LLW; disposal scenarios and alternative treatment options for LLW; methods and models which could be used to assess and compare risks associated with land and ocean options for LLW disposal; technical and methodological issues associated with comparing risks of different options; and, roles of decision making approaches in comparing risks across media. 63 refs., 23 figs., 33 tabs.

  16. Concepts and data-collection techniques used in a study of the unsaturated zone at a low-level radioactive-waste disposal site near Sheffield, Illinois

    USGS Publications Warehouse

    Healy, R.W.; DeVries, M.P.; Striegl, R.G.

    1986-01-01

    A study of water and radionuclide movement through the unsaturated zone is being conducted at the low level radioactive waste disposal site near Sheffield, Illinois. Included in the study are detailed investigations of evapotranspiration, movement of water through waste trench covers, and movement of water and radionuclides (dissolved and gaseous) from the trenches. An energy balance/Bowen ratio approach is used to determine evapotranspiration. Precipitation, net radiation, soil-heat flux, air temperature and water vapor content gradients, wind speed, and wind direction are measured. Soil water tension is measured with tensiometers which are connected to pressure transducers. Meteorological sensors and tensiometers which are connected to pressure transducers. Meteorological sensors and tensiometers are monitored with automatic data loggers. Soil moisture contents are measured through small-diameter access tubes with neutron and gamma-ray attenuation gages. Data beneath the trenches are obtained through a 130-meter-long tunnel which extends under four of the trenches. Water samples are obtained with suction lysimeters, and samples of the geologic material are obtained with core tubes. These samples are analyzed for radiometric and inorganic chemistry. Gas samples are obtained from gas piezometers and analyzed for partial pressures of major constituents, Radon-222, tritiated water vapor, and carbon-14 dioxide. (USGS)

  17. Genesis and continuity of quaternary sand and gravel in glacigenic sediment at a proposed low-level radioactive waste disposal site in east-central Illinois

    USGS Publications Warehouse

    Troost, K.G.; Curry, B. Brandon

    1991-01-01

    The Illinois Department of Nuclear Safety has characterized the Martinsville Alternative Site (MAS) for a proposed low-level radioactive waste disposal facility. The MAS is located in east-central Illinois approximately 1.6 km (1 mi) north of the city of Martinsville. Geologic investigation of the 5.5-km2 (1380-acre) site revealed a sequence of chiefly Illinoian glacigenic sediments from 6 to 60 m (20-200 ft) thick overlying two major bedrock valleys carved in Pennsylvanian strata. Relatively permeable buried units include basal, preglacial alluvium; a complex of intraglacial and subglacial sediment; englacial deposits; and supraglacial fluvial deposits. Postglacial alluvium underlies stream valleys on and adjacent to the site. In most areas, the buried sand units are confined by low-permeability till, lacustrine sediment, colluvium, and loess. The distribution and thickness of the most extensive and continuous buried sand units have been modified considerably by subglacial erosion, and their distributions have been influenced by the buried bedrock valleys. The most continuous of the various sand units were deposited as preglacial and postglacial alluvium and are the uppermost and lowermost stratigraphic units at the alternative site. Sand units that were deposited in englacial or ice-marginal environments are less continuous. Aquifer pumping tests, potentiometric head data, and groundwater geochemistry analyses indicate minimal interaction of groundwater across localized interconnections of the permeable units. ?? 1991 Springer-Verlag New York Inc.

  18. Evaluation of trench subsidence and stabilization at Sheffield low-level radioactive waste disposal facility. Technical report (final) 15 Oct 80-30 Mar 81

    SciTech Connect

    Kahle, R.; Rowlands, J.

    1981-05-01

    This report presents the results of the evaluation of trench subsidence and possible future stabilization techniques at the Sheffield Low-Level Radioactive Waste Disposal Facility, Sheffield, Illinois. The investigation was based on a review, analysis and summary of available surface maintenance records on the site, and other data obtained from the site operator, the U.S. Nuclear Regulatory Commission, the U.S. Geological Survey, and the Illinois Department of Nuclear Safety. Analyses were performed to determine subsidence trends and project future subsidence for 21 trenches into which the wastes were placed. The types of subsidence, potholes, sudden slumps, and long term area settlement were evaluated to develop future projections. The mechanisms evaluated as causing subsidence and settlement were: piping and settlement of the trench backfill soil into voids, consolidation of the trench backfill soil, and deterioration of the waste containers and wastes by corrosion and biodegradation. The engineering feasibility and costs of potential trench stabilization techniques were developed. Recommendations were made for stabilization, final capping, and future monitoring of each trench.

  19. Face seal assembly for rotating drum

    DOEpatents

    Morgan, J. Giles; Rennich, Mark J.; Whatley, Marvin E.

    1982-01-01

    A seal assembly comprises a tube rotatable about its longitudinal axis and having two longitudinally spaced flanges projecting radially outwardly from the outer surface thereof. Slidably positioned against one of the flanges is a seal ring, and disposed between this seal ring and the other flange are two rings that are forced apart by springs, one of the latter rings being attached to a flexible wall.

  20. Solid oxide fuel cell having a glass composite seal

    DOEpatents

    De Rose, Anthony J.; Mukerjee, Subhasish; Haltiner, Jr., Karl Jacob

    2013-04-16

    A solid oxide fuel cell stack having a plurality of cassettes and a glass composite seal disposed between the sealing surfaces of adjacent cassettes, thereby joining the cassettes and providing a hermetic seal therebetween. The glass composite seal includes an alkaline earth aluminosilicate (AEAS) glass disposed about a viscous glass such that the AEAS glass retains the viscous glass in a predetermined position between the first and second sealing surfaces. The AEAS glass provides geometric stability to the glass composite seal to maintain the proper distance between the adjacent cassettes while the viscous glass provides for a compliant and self-healing seal. The glass composite seal may include fibers, powders, and/or beads of zirconium oxide, aluminum oxide, yttria-stabilized zirconia (YSZ), or mixtures thereof, to enhance the desirable properties of the glass composite seal.

  1. Ferrules seals

    DOEpatents

    Smith, James L.

    1984-01-01

    A device is provided for sealing an inner tube and an outer tube without excessively deforming the tubes. The device includes two ferrules which cooperate to form a vacuum-tight seal between the inner tube and outer tube and having mating surfaces such that overtightening is not possible.

  2. Ferrules seals

    DOEpatents

    Smith, J.L.

    1984-07-10

    A device is provided for sealing an inner tube and an outer tube without excessively deforming the tubes. The device includes two ferrules which cooperate to form a vacuum-tight seal between the inner tube and outer tube and having mating surfaces such that overtightening is not possible. 3 figs.

  3. Composition and Transport of Volatile Organic Compounds Near a Chemical and Radioactive Waste Disposal Facility in an Arid Environment with a Thick Unsaturated Zone

    NASA Astrophysics Data System (ADS)

    Baker, R. J.; Andraski, B. J.; Stonestrom, D. A.; Luo, W.

    2010-12-01

    Volatile organic compounds (VOCs) and low-level radioactive waste (LLRW) materials commonly occur together in mixed-waste disposal facilities. Volatile components of both waste types can be transported simultaneously away from the site through the unsaturated zone. Concentrations, variability, and transport of VOCs near mixed-waste-disposal facilities in arid environments remain poorly understood. In this study, plume-scale VOC composition of the deep and shallow unsaturated zone near such a facility in southwestern Nevada was observed over a 10-year period. Spatial and temporal variability of VOC concentrations were monitored, and vertical (upward) fluxes of VOCs through the unsaturated zone to the land surface were estimated. Vapor-phase samples were collected from two boreholes, each instrumented with 10-12 vapor-sampling ports at irregular intervals that extend the entire depth of the110-m unsaturated zone and are located 100 and 160 m away from the nearest LLRW trench. Also, an array of eight shallow (0.5- and 1.5-m depths) vapor-probe sets extending from 0-400 m from the LLRW facility was monitored. Chlorfluorocarbons (CFCs) constitute ~60 percent of total VOC mass, far more than any other compound or class. Chlorinated solvent chemicals (~29 percent) and gasoline-range hydrocarbons (~1 percent) also were detected in most sampling locations. Shallow and deep samples indicate VOC concentrations in the vapor plume are increasing with time and moving further off site. The highest total VOC concentration observed was about 47,000 ppbv. Vertical profiles of VOC concentrations implies a preferential lateral flow path at 20-40 m below land surface, and upward and downward diffusive fluxes away from the zone of peak concentrations. The coarse gravel in this depth interval appears to provide less resistance to vapor-phase transport than the finer-textured sediment layers above and below. VOC concentrations at 0.5 and 1.5 m below land surface and laboratory

  4. Effects of low-level radioactive-waste disposal on water chemistry in the unsaturated zone at a site near Sheffield, Illinois, 1982-84

    USGS Publications Warehouse

    Peters, C.A.; Striegl, R.G.; Mills, P.C.; Healy, R.W.

    1992-01-01

    A 1982-84 field study defined the chemistry of water collected from the unsaturated zone at a low-level radioactive-waste disposal site near Sheffield, Bureau County, Ill. Chemical data were evaluated to determine the principal, naturally occurring geochemical reactions in the unsaturated zone and to evaluate waste-induced effects on pore-water chemistry. Samples of precipitation, unsaturated-zone pore water, and saturated-zone water were analyzed for specific conductance, pH, alkalinity, major cations and anions, dissolved organic carbon, gross alpha and beta radiation, and tritium. Little change in concentration of most major constituents in the unsaturated-zone water was observed with respect to depth or distance from disposal trenches. Tritium and dissolved organic carbon concentrations were, however, dependent on proximity to trenches. The primary reactions, both on-site and off-site, were carbonate and clay dissolution, cation exchange, and the oxidation of pyrite. The major difference between on-site and off-site inorganic water chemistry resulted from the removal of the Roxana Silt and the Radnor Till Member of the Glasford Formation from on-site. Off-site, the Roxana Silt contributed substantial quantities of sodium to solution from montmorillonite dissolution and associated cation-exchange reactions. The Radnor Till Member provided exchange surfaces for magnesium. Precipitation at the site had an ionic composition of calcium zinc sulfate and an average pH of 4.6. Within 0.3 meter of the land surface, infiltrating rainwater or snowmelt changed to an ionic composition of calcium sulfate off-site and calcium bicarbonate on-site and had an average pH of 7.9; below that depth, pH averaged 7.5 and the ionic composition generally was calcium magnesium bicarbonate. Alkalinity and specific conductance differed primarily according to composition of geologic materials. Tritium concentrations ranged from 0.2 (detection limit) to 1,380 nanocuries per liter. The

  5. Effects of low-level radioactive-waste disposal on water chemistry in the unsaturated zone at a site near Sheffield, Illinois, 1982-84

    USGS Publications Warehouse

    Peters, C.A.; Striegl, R.G.; Mills, P.C.; Healy, R.W.

    1992-01-01

    A 1982-84 field study defined the chemistry of water collected from the unsaturated zone at a low-level radioactive-waste disposal site near Sheffield, Bureau County, Illinois. Chemical data were evaluated to determine the principal naturally occurring geochemical reactions in the unsaturated zone and to evaluate waste-induced effects on pore-water chemistry. Samples of precipitation, unsaturated-zone pore water, and saturated-zone water were analyzed for specific conductance, pH, alkalinity, major cations and anions, dissolved organic carbon, gross alpha and beta radiation, and tritium. Little change in concentration of most major constituents in the unsaturated-zone water was observed with respect to depth or distance from disposal trenches. Tritium and dissolved organic carbon concentrations were, however, dependent on proximity to trenches. The primary reactions, both on- site and off-site, were carbonate and clay dissolution, cation exchange, and the oxidation of pyrite. The major difference between on-site and off-site inorganic water chemistry resulted from the removal of the Roxana Silt and the Radnor Till Member of the Glasford Formation from on-site. Off-site, the Roxana Silt contributed substantial quantities of sodium to solution from montmorillonite dissolution and associated cation-exchange reactions. The Radnor Till Member provided exchange surfaces for magnesium. Precipitation at the site had an ionic composition of calcium zinc sulfate and an average pH of 4.6. Within 0.3 meter of the land surface, infiltrating rain water or snowmelt changed to an ionic canposition of calcium sulfate off-site and calcium bicarbonate on-site and had an average pH of 7.9; below that depth, pH averaged 7.5 and the ionic composition generally was calcium magnesium bicarbonate. Alkalinity and specific conductance differed primarily according to composition of geologic materials. Tritium concentrations ranged from 0.2 (detection limit) to 1,380 nanocuries per liter. The

  6. Liquid sodium dip seal maintenance system

    DOEpatents

    Briggs, Richard L.; Meacham, Sterling A.

    1980-01-01

    A system for spraying liquid sodium onto impurities associated with liquid dip seals of nuclear reactors. The liquid sodium mixing with the impurities dissolves the impurities in the liquid sodium. The liquid sodium having dissolved and diluted the impurities carries the impurities away from the site thereby cleaning the liquid dip seal and surrounding area. The system also allows wetting of the metallic surfaces of the dip seal thereby reducing migration of radioactive particles across the wetted boundary.

  7. Steam turbine high pressure vent and seal system

    SciTech Connect

    Groenendaal, J.C. Jr.; Brown, B.

    1987-04-28

    A steam turbine is described comprising: an outer cylinder; an inner cylinder disposed within the outer cylinder; a blade ring disposed partially within the inner cylinder and partially within the outer cylinder; a nozzle chamber assembly disposed within the inner cylinder for introducing motive steam to the turbine and having nozzle chamber and nozzle block portions; a rotor having circular array of rotatable blades and a thrust balance piston disposed thereon; a dummy ring disposed within one end of the inner cylinder adjacent the balance piston; labyrinth sealing means disposed between the dummy ring and the balance piston forming a rotating seal.

  8. Seal arrangement

    DOEpatents

    Lundholm, Gunnar

    1987-01-01

    A seal arrangement is provided for preventing gas leakage along a reciprocating piston rod or other reciprocating member passing through a wall which separates a high pressure gas chmber and a low pressure gas chamber. Liquid lubricant is applied to the lower pressure side of a sealing gland surrounding the piston rod to prevent the escape of gas between the rod and the gland. The sealing gland is radially forced against the piston rod by action of a plurality of axially stacked O-rings influenced by an axially acting spring as well as pressure from the gas.

  9. Water and tritium movement through the unsaturated zone at a low-level radioactive-waste disposal site near Sheffield, Illinois, 1981-85

    USGS Publications Warehouse

    Mills, Patrick C.; Healy, R.W.

    1991-01-01

    The movement of water and tritium through the unsaturated zone was studied at a low-level radioactive-waste disposal site near Sheffield, Bureau County, Illinois, from 1981 to 1985. Water and tritium movement occurred in an annual, seasonally timed cycle; recharge to the saturated zone generally occurred in the spring and early summer. Mean annual precipitation (1982-85) was 871 millimeters; mean annual recharge to the disposal trenches (July 1982 through June 1984) was estimated to be 107 millimeters. Average annual tritium flux below the study trenches was estimated to be 3.4 millicuries per year. Site geology, climate, and waste-disposal practices influenced the spatial and temporal variability of water and tritium movement. Of the components of the water budget, evapotranspiration contributed most to the temporal variability of water and tritium movement. Disposal trenches are constructed in complexly layered glacial and postglacial deposits that average 17 meters in thickness and overlie a thick sequence of Pennsylvanian shale. The horizontal saturated hydraulic conductivity of the clayey-silt to sand-sized glacial and postglacial deposits ranges from 4.8x10^-1 to 3.4x10^4 millimeters per day. A 120-meter-long horizontal tunnel provided access for hydrologic measurements and collection of sediment and water samples from the unsaturated and saturated geologic deposits below four disposal trenches. Trench-cover and subtrench deposits were monitored with soil-moisture tensiometers, vacuum and gravity lysimeters, piezometers, and a nuclear soil-moisture gage. A cross-sectional, numerical ground-water-flow model was used to simulate water movement in the variably saturated geologic deposits in the tunnel area. Concurrent studies at the site provided water-budget data for estimating recharge to the disposal trenches. Vertical water movement directly above the trenches was impeded by a zone of compaction within the clayey-silt trench covers. Water entered the

  10. Water and tritium movement through the unsaturated zone at a low-level radioactive-waste disposal site near Sheffield, Illinois, 1981-85

    USGS Publications Warehouse

    Mills, Patrick C.; Healy, Richard W.

    1993-01-01

    The movement of water and tritium through the unsaturated zone was studied at a low-level radioactive-waste disposal site near Sheffield, Bureau County, Illinois, from 1981 to 1985. Water and tritium movement occurred in an annual, seasonally timed cycle; recharge to the saturated zone generally occurred in the spring and early summer. Mean annual precipitation (1982-85) was 871 mm (millimeters); mean annual recharge to the disposal trenches (July 1982 through June 1984) was estimated to be 107 mm. Average annual tritium flux below the study trenches was estimated to be 3.4 mCi/yr (millicuries per year). Site geology, climate, and waste-disposal practices influenced the spatial and temporal variability of water and tritium movement. Of the components of the water budget, evapotranspiration contributed most to the temporal variability of water and tritium movement. Disposal trenches are constructed in complexly layered glacial and postglacial deposits that average 17 m (meters) in thickness and overlie a thick sequence of Pennsylvanian shale. The horizontal saturated hydraulic conductivity of the clayey-silt to sand-sized glacial and postglacial deposits ranges from 4.8x10 -1 to 3.4x10 4 mm/d (millimeters per day). A 120-m-long horizontal tunnel provided access for hydrologic measurements and collection of sediment and water samples from the unsaturated and saturated geologic deposits below four disposal trenches. Trench-cover and subtrench deposits were monitored with soil-moisture tensiometers, vacuum and gravity lysimeters, piezometers, and a nuclear soil-moisture gage. A cross-sectional, numerical ground-water-flow model was used to simulate water movement in the variably saturated geologic deposits in the tunnel area. Concurrent studies at the site provided water-budget data for estimating recharge to the disposal trenches. Vertical water movement directly above the trenches was impeded by a zone of compaction within the clayey-silt trench covers. Water entered

  11. Long-term cement corrosion in chloride-rich solutions relevant to radioactive waste disposal in rock salt - Leaching experiments and thermodynamic simulations

    NASA Astrophysics Data System (ADS)

    Bube, C.; Metz, V.; Bohnert, E.; Garbev, K.; Schild, D.; Kienzler, B.

    Low- and intermediate-level radioactive wastes are frequently solidified in a cement matrix. In a potential repository for nuclear wastes, the cementitious matrix is altered upon contact with solution and the resulting secondary phases may provide for significant retention of the radionuclides incorporated in the wastes. In order to assess the secondary phases formed upon corrosion in chloride-rich solutions, which are relevant for nuclear waste disposal in rock salt, leaching experiments were performed. Conventional laboratory batch experiments using powdered hardened cement paste in MgCl2-rich solutions were left to equilibrate for up to three years and full-scale cemented waste products were exposed to NaCl-rich and MgCl2-rich solutions for more than twenty years, respectively. Solid phase analyses revealed that corrosion of hardened cement in MgCl2-rich solutions advanced faster than in NaCl-rich solutions due to the extensive exchange of Mg from solution against Ca from the cementitious solid. Thermodynamic equilibrium simulations compared well to results at the final stages of the respective experiments indicating that close to equilibrium conditions were reached. At high cement product to brine ratios (>0.65 g mL-1), the solution composition in the laboratory-scale experiments was close to that of the full-scale experiments (cement to brine ratio of 2.5 g mL-1) in the MgCl2 systems. The present study demonstrates the applicability of thermodynamic methods used in this approach to adequately describe full-scale long-term experiments with cemented waste simulates.

  12. Definitive design report: Design report project W-025, Radioactive Mixed Waste (RMW) Land Disposal Facility NON-DRAG-OFF. Revision 1, Volume 1 and 2

    SciTech Connect

    Roscha, V.

    1994-11-29

    The purpose of this report is to describe the definitive design of the Radioactive Mixed Waste (RMW) Non-Drag-Off disposal facility, Project W-025. This report presents a n of the major landfill design features and a discussion of how each of the criteria is addressed in the design. The appendices include laboratory test results, design drawings, and individual analyses that were conducted in support of the design. Revision 1 of this document incorporates design changes resulting from an increase in the required operating life of the W-025 landfill from 2 to 20 years. The rationale for these design changes is described in Golder Associates Inc. 1991a. These changes include (1) adding a 1.5-foot-thick layer of compacted admix directory-under the primary FML on the floor of the landfill to mitigate the effects of possible stress cracking in the primary flexible membrane liner (FML), and (2) increasing the operations layer thickness from two to three feet over the entire landfill area, to provide additional protection for the secondary admix layer against mechanical damage and the effects of freezing and desiccation. The design of the W-025 Landfill has also been modified in response to the results of the EPA Method 9090 chemical compatibility testing program (Golder Associates Inc. 1991b and 1991c), which was completed after the original design was prepared. This program consisted of testing geosynthetic materials and soil/bentonite admix with synthetic leachate having the composition expected during the life of the W-025 Landfill., The results of this program indicated that the polyester geotextile originally specified for the landfill might be susceptible to deterioration. On this basis, polypropylene geotextiles were substituted as a more chemically-resistant alternative. In addition, the percentage of bentonite in the admix was increased to provide sufficiently low permeability to the expected leachate.

  13. Structural constraints for proposed Fort Hancock low-level radioactive waste disposal site (NTP-S34), southern Hudspeth County, Texas

    SciTech Connect

    Lemone, D.V.

    1989-03-01

    Structural complexities reduce the homogeneity necessary for a site characterization model to an unacceptable level for performance assessment for radioactive waste disposal sites. The proposed site lies between the northern, stable Diablo platform and the southern, mobile Mesozoic Chihuahua tectonic belt. Structural movement along this interface has been active for the past 14,000 years. In addition, the area lies along the northern margin of the Permian Marfa basin and the northeastern margin of the deeply faulted Hueco bolson segment of the late Cenozoic Rio Grande rift system. Recent seismic activity with extensive surface rupture in Quitman Canyon (30 mi southeast of the site) is also documented from the 1931 Valentine, Texas, earthquake (6.4 Richter scale). The site is underlain by either a thrust fault or the complex terminus of a Mesozoic thrust fault. This fault is a segment of the continuous thrust sheet extending from exposures in the Sierra Blanc area, 30 mi east (Devil Ridge fault), to the El Paso area west (Rio Grande fault). This segment of the Devil Ridge-Rio Grande thrust is documented by the Haymond Krupp No. 1 Thaxton wildcat drilled at Campogrande Mountain immediately south of the site. The recent rift fault scarp (Campo Grande) immediately south of the Thaxton well has a 17-mi surface trace and is, no doubt, related to the subsurface Clint fault to the west in the El Paso area. An additional complexity is the presence of a monoclinal flexure with a minimum of 900 ft of surface relief (2 mi northeast of NTP-S34). A 4.5-mi, east-west, down-to-the-south normal fault occurs near the top of the monocline with a small associated graben. These complexities seriously compromise the proposed Fort Hancock site.

  14. Ground-water hydrology and subsurface migration of radioisotopes at a low-level solid radioactive-waste disposal site, West Valley, New York

    USGS Publications Warehouse

    Prudic, David E.; Randall, Allan D.

    1977-01-01

    Burial trenches for disposal of solid radioactive waste at West Valley, N.Y., are excavated in till that has very low hydraulic conductivity (about 5 x 10 to the minus 8th power centimeters per second). Fractures and root tubes with chemically oxidized and (or) reduced soil in their walls extend to 3 to 4.5 meters below natural land surface. Preliminary simulations of pressure heads with a digital model suggest that hydraulic conductivity is an order of magnitude greater in the fractured till near land surface than at greater depth. Hydraulic gradients are predominantly downward, even beneath small valleys. The upper part of a body of underlying lacustrine silt is unsaturated; in the lower, saturated part, slow lateral flow may occur. In the older trenches, water began to build up in 1971, overflowed briefly in 1975, and was pumped out in 1975-76. Water levels rose abruptly during major rainstorms in mid-1975, indicating rapid infiltration through cracks in the cover material. The new trenches have maintained low, stable water levels, perhaps because of thicker, more compact cover and less waste settlement; pressure heads near these trenches are low, locally approaching zero, perhaps because of slight infiltration and limited near-surface storage. Peak tritium concentrations in test-hole cores (generally 0.00001 to 0.001 microcuries per milliliter) were found within 3 meters of land surface and are attributed to surface contamination. Concentrations declined rapidly with depth within the fractured till; secondary peaks found at about 9 meters in three holes are attributed to lateral migration from trenches. Other radioisotopes were detected only near land surface. Samples from the walls of shallow fractures revealed no accumulation of radioisotopes. (Woodard-USGS)

  15. Radioactive Waste.

    ERIC Educational Resources Information Center

    Blaylock, B. G.

    1978-01-01

    Presents a literature review of radioactive waste disposal, covering publications of 1976-77. Some of the studies included are: (1) high-level and long-lived wastes, and (2) release and burial of low-level wastes. A list of 42 references is also presented. (HM)

  16. INEEL special case waste storage and disposal alternatives

    SciTech Connect

    Larson, L.A.; Bishop, C.W.; Bhatt, R.N.

    1997-07-01

    Special case waste is historically defined as radioactive waste that does not have a path forward or fit into current Department of Energy management plans for final treatment or disposal. The objectives of this report, relative to special case waste at the Idaho National Engineering and Environmental Laboratory, are to (a) identify its current storage locations, conditions, and configuration; (b) review and verify the currently reported inventory; (c) segregate the inventory into manageable categories; (d) identify the portion that has a path forward or is managed under other major programs/projects; (e) identify options for reconfiguring and separating the disposable portions; (f) determine if the special case waste needs to be consolidated into a single storage location; and (g) identify a preferred facility for storage. This report also provides an inventory of stored sealed sources that are potentially greater than Class C or special case waste based on Nuclear Regulatory Commission and Site-Specific Waste Acceptance Criteria.

  17. Pre-sealing risk analysis

    SciTech Connect

    Ensminger, D.A.; Hough, M.E.; Oston, S.G.

    1980-01-07

    This report describes studies of accidents involving high-level radioactive waste before sealing the waste into a repository. The report summarizes work done in this area during Fiscal Year 1978 and supplements previous work. Models of accident probability, severity, and consequences are refined and extended.

  18. Bentonite as a waste isolation pilot plant shaft sealing material

    SciTech Connect

    Daemen, J.; Ran, Chongwei

    1996-12-01

    Current designs of the shaft sealing system for the Waste Isolation Pilot Plant (WIPP) propose using bentonite as a primary sealing component. The shaft sealing designs anticipate that compacted bentonite sealing components can perform through the 10,000-year regulatory period and beyond. To evaluate the acceptability of bentonite as a sealing material for the WIPP, this report identifies references that deal with the properties and characteristics of bentonite that may affect its behavior in the WIPP environment. This report reviews published studies that discuss using bentonite as sealing material for nuclear waste disposal, environmental restoration, toxic and chemical waste disposal, landfill liners, and applications in the petroleum industry. This report identifies the physical and chemical properties, stability and seal construction technologies of bentonite seals in shafts, especially in a saline brine environment. This report focuses on permeability, swelling pressure, strength, stiffness, longevity, and densification properties of bentonites.

  19. Quick-sealing design for radiological containment

    DOEpatents

    Rampolia, Donald S.; Speer, Elmer

    1990-01-01

    A quick-sealing assembly and method for forming an adhesive seal on opposite sides of a mechanical seal for a flexible containment bag of the type used for working with radioactively contaminated objects. The assembly includes an elongated mechanical fastener having opposing engaging members affixed at a predetermined distance from each of the elongated edges, with an adhesive layer formed between the mechanical fastener and the elongated edge such that upon engagement of the mechanical fastener and adhesive layers to opposing containment fabric, a neat triple hermetic seal is formed.

  20. Quick-sealing design for radiological containment

    DOEpatents

    Rampolla, Donald S.; Speer, Elmer

    1991-01-01

    A quick-sealing assembly and method for forming an adhesive seal on opposite sides of a mechanical seal for a flexible containment bag of the type used for working with radioactively contaminated objects. The assembly includes an elongated mechanical fastener having opposing engaging members affixed at a predetermined distance from each of the elongated edges, with an adhesive layer formed between the mechanical fastener and the elongated edge such that upon engagement of the mechanical fastener and adhesive layers to opposing containment fabric, a neat triple hermetic seal is formed.

  1. Compilation and preliminary interpretation of hydrologic data for the Weldon Spring radioactive waste-disposal sites, St Charles County, Missouri; a progress report

    USGS Publications Warehouse

    Kleeschulte, M.J.; Emmett, L.F.

    1986-01-01

    The Weldon Spring Chemical Plant is located just north of the drainage divide separating the Mississippi River and the Missouri River in St. Charles County, Missouri. From 1957 to 1966 the plant converted uranium-ore concentrates and recycled scrap to pure uranium trioxide, uranium tetrafluoride, and uranium metal. Residues from these operations were pumped to four large pits that had been excavated near the plant. Small springs and losing streams are present in the area. Water overlying the residue in the pits has a large concentration of dissolved solids and a different chemical composition compared to the native groundwater and surface water. This difference is indicated by the concentrations of calcium, sodium, sulfate, nitrate, fluoride, uranium, radium, lithium, molybdenum, strontium, and vanadium, all of which are greater than natural or background concentrations. Water from Burgermeister Spring, located about 1.5 miles north of the chemical plant area, contains uranium and nitrate concentrations greater than background concentrations. Groundwater in the shallow bedrock aquifer moves northward from the vicinity of the chemical plant toward Dardenne Creek. An abandoned limestone quarry several miles southwest of the chemical plant also has been used for the disposal of radioactive waste and rubble. Groundwater flow from the quarry area is southward through the alluvium, away from the quarry and toward the Missouri River. The St. Charles County well field is located in the Missouri River flood plain near the quarry and the large yield wells are open to the Missouri River alluvial aquifer. Water from a well 4,000 ft southeast of the quarry was analyzed; there was no indication of contamination from the quarry. Additional water quality and water level data are needed to determine if water from the quarry moves toward the well field. Observation wells need to be installed in the area between the chemical plant, pits, and Dardenne Creek. The wells would be used to

  2. Anaerobic sealing

    SciTech Connect

    Hayre, J.

    1986-05-01

    Anaerobic sealants offer an alternative to conventional methods of joint repair on mains operating at low and medium pressures. The method does not require highly skilled personnel who are diligent in ensuring that the necessary standards of preparation and seal application are achieved. British Gas' experience has shown that lead joints that do not contain yarn or where the yarn has deteriorated are difficult to seal. The evidence so far indicates that yarn is important in ensuring that the low viscosity sealant rapidly wicks around the joint during the injection operation. It is obvious that more research and development is needed in this field, but anaerobic sealing of leaking joints in an effective, innovative method of joint repair.

  3. Dual rotating shaft seal apparatus

    DOEpatents

    Griggs, J.E.; Newman, H.J.

    1983-06-16

    The report is directed to apparatus suitable for transferring torque and rotary motion through a wall in a manner which is essentially gas impermeable. The apparatus can be used for pressurizing, agitating, and mixing fluids and features two ferrofluidic, i.e., ferrometic seals. Each seal is disposed on one of two supported shafts and each shaft is operably connected at one end to a gear mechanism and at its other end to an adjustable coupling means which is to be connected to a rotatable shaft extending through a wall through which torque and rotary motion are to be transferred.

  4. An Internal Coaxil Cable Seal System

    DOEpatents

    Hall, David R.; Hall, Jr., H. Tracy; Pixton, David; Dahlgren, Scott; Sneddon, Cameron; Briscoe, Michael; Fox, Joe

    2004-12-23

    The invention is a seal system for a coaxial cable more specifically an internal seal system placed within the coaxial cable and its constituent components. A series of seal stacks including flexible rigid rings and elastomeric rings are placed on load bearing members within the coaxial cable. The current invention is adapted to seal the annular space between the coaxial cable and an electrical contact passing there through. The coaxial cable is disposed within drilling components to transmit electrical signals between drilling components within a drill string. During oil and gas exploration, a drill string can see a range of pressures and temperatures thus resulting in multiple combinations of temperature and pressure and increasing the difficulty of creating a robust seal for all combinations. The seal system can be used in a plurality of downhole components, such as sections of pipe in a drill string, drill collars, heavy weight drill pipe, and jars.

  5. Bench-scale treatability testing of biological, UV oxidation, distillation, and ion-exchange treatment of trench water from a low-level radioactive waste disposal area at West Valley, New York

    SciTech Connect

    Sundquist, J.A.; Gillings, J.C.; Sonntag, T.L.; Denault, R.P.

    1993-03-01

    Ecology and Environment, Inc. (E and E), under subcontract to Pacific Nuclear Services (PNS), conducted for the New York State Energy Research and Development Authority (NYSERDA) treatability tests to support the selection and design of a treatment system for leachate from Trench 14 of the West Valley State-Licensed, Low-Level Radioactive Waste Disposal Area (SDA). In this paper E and E presents and discusses the treatability test results and provides recommendations for the design of the full-scale treatment system.

  6. Fuel cell separator with compressible sealing flanges

    DOEpatents

    Mientek, Anthony P.

    1985-04-30

    A separator for separating adjacent fuel cells in a stack of such cells includes a flat, rectangular, gas-impermeable plate disposed between adjacent cells and having two opposite side margins thereof folded back over one side of the plate to form two first seal flanges and having the other side margins thereof folded back over the opposite side of the plate to form two second seal flanges, each of the seal flanges cooperating with the plate to define a channel in which is disposed a resiliently compressible stack of thin metal sheets. The two first seal flanges cooperate with the electrolyte matrix of one of the cells to form a gas-impermeable seal between an electrode of the one cell and one of two reactant gas manifolds. The second seal flanges cooperate with the electrolyte matrix of the other cell for forming a gas-impermeable seal between an electrode of the other cell and the other of the two reactant gas manifolds. The seal flanges cooperate with the associated compressible stacks of sheets for maintaining a spacing between the plate and the electrolyte matrices while accommodating variation of that spacing.

  7. Fuel cell separator with compressible sealing flanges

    DOEpatents

    Mientek, A.P.

    1984-03-30

    A separator for separating adjacent fuel cells in a stack of such cells includes a flat, rectangular, gas-impermeable plate disposed between adjacent cells and having two opposite side margins thereof folded back over one side of the plate to form two first seal flanges and having the other side margins thereof folded back over the opposite side of the plate to form two second seal flanges, each of the seal flanges cooperating with the plate to define a channel in which is disposed a resiliently compressible stack of thin metal sheets. The two first seal flanges cooperate with the electrolyte matrix of one of the cells to form a gas-impermeable seal between an electrode of the one cell and one of two reactant gas manifolds. The second seal flanges cooperate with the electrolyte matrix of the other cell for forming a gas-impermeable seal between an electrode of the other cell and the other of the two reactant gas manifolds. The seal flanges cooperate with the associated compressible stacks of sheets for maintaining a spacing between the plate and the electrolyte matrices while accommodating variation of that spacing.

  8. Core disruptive accident margin seal

    DOEpatents

    Garin, John; Belsick, James C.

    1978-01-01

    An apparatus for sealing the annulus defined between a substantially cylindrical rotatable first riser assembly and plug combination disposed in a substantially cylindrical second riser assembly and plug combination of a nuclear reactor system. The apparatus comprises a flexible member disposed between the first and second riser components and attached to a metal member which is attached to an actuating mechanism. When the actuating mechanism is not actuated, the flexible member does not contact the riser components thus allowing the free rotation of the riser components. When desired, the actuating mechanism causes the flexible member to contact the first and second riser components in a manner to block the annulus defined between the riser components, thereby sealing the annulus between the riser components.

  9. Python fiber optic seal

    SciTech Connect

    Ystesund, K.; Bartberger, J.; Brusseau, C.; Fleming, P.; Insch, K.; Tolk, K.

    1993-08-01

    Sandia National Laboratories has developed a high security fiber optic seal that incorporates tamper resistance features that are not available in commercial fiber optic seals. The Python Seal is a passive fiber optic loop seal designed to give indication of unauthorized entry. The seal includes a fingerprint feature that provides seal identity information in addition to the unique fiber optic pattern created when the seal is installed. The fiber optic cable used for the seal loop is produced with tamper resistant features that increase the difficulty of attacking that component of a seal. A Seal Reader has been developed that will record the seal signature and the fingerprint feature of the seal. A Correlator software program then compares seal images to establish a match or mismatch. SNL is also developing a Polaroid reader to permit hard copies of the seal patterns to be obtained directly from the seal.

  10. Waste disposal package

    DOEpatents

    Smith, M.J.

    1985-06-19

    This is a claim for a waste disposal package including an inner or primary canister for containing hazardous and/or radioactive wastes. The primary canister is encapsulated by an outer or secondary barrier formed of a porous ceramic material to control ingress of water to the canister and the release rate of wastes upon breach on the canister. 4 figs.

  11. Radionuclides, Heavy Metals, and Polychlorinated Biphenyls in Soils Collected Around the Perimeter of Low-Level Radioactive Waste Disposal Area G during 2006

    SciTech Connect

    P. R. Fresquez

    2007-02-28

    Twenty-one soil surface samples were collected in March around the perimeter of Area G, the primary disposal facility for low-level radioactive solid waste at Los Alamos National Laboratory (LANL). Three more samples were collected in October around the northwest corner after elevated tritium levels were detected on an AIRNET station located north of pit 38 in May. Also, four soil samples were collected along a transect at various distances (48, 154, 244, and 282 m) from Area G, starting from the northeast corner and extending to the Pueblo de San Ildefonso fence line in a northeasterly direction (this is the main wind direction). Most samples were analyzed for radionuclides ({sup 3}H, {sup 238}Pu, {sup 239,240}Pu, {sup 241}Am, {sup 234}U, {sup 235}U, and {sup 238}U), inorganic elements (Al, Ba, Be, Ca, Cr, Co, Cu, Fe, Mg, Mn, Ni, K, Na, V, Hg, Zn, Sb, As, Cd, Pb, Se, Ag, and Tl) and polychlorinated biphenyl (PCB) concentrations. As in previous years, the highest levels of {sup 3}H in soils (690 pCi/mL) were detected along the south portion of Area G near the {sup 3}H shafts; whereas, the highest concentrations of {sup 241}Am (1.2 pCi/g dry) and the Pu isotopes (1.9 pCi/g dry for {sup 238}Pu and 5 pCi/g dry for {sup 239,240}Pu) were detected along the northeastern portions near the transuranic waste pads. Concentrations of {sup 3}H in three soil samples and {sup 241}Am and Pu isotopes in one soil sample collected around the northwest corner in October increased over concentrations found in soils collected at the same locations earlier in the year. Almost all of the heavy metals, with the exception of Zn and Sb in one sample each, in soils around the perimeter of Area G were below regional statistical reference levels (mean plus three standard deviations) (RSRLs). Similarly, only one soil sample collected on the west side contained PCB concentrations--67 {micro}g/kg dry of aroclor-1254 and 94 {micro}g/kg dry of aroclor-1260. Radionuclide and inorganic element

  12. GAS SEAL

    DOEpatents

    Monson, H.; Hutter, E.

    1961-07-11

    A seal is described for a cover closing an opening in the top of a pressure vessel that may house a nuclear reactor. The seal comprises a U-shaped trough formed on the pressure vessel around the opening therein, a mass of metal in the trough, and an edge flange on the cover extending loosely into the trough and dipping into the metal mass. The lower portion of the metal mass is kept melted, and the upper portion, solid. The solid pontion of the metal mass prevents pressure surges in the vessel from expelling the liquid portion of the metal mass from the trough; the liquld portion, thus held in place by the solid portion, does not allow gas to go through, and so gas cannot escape through shrinkage holes in the solid portion.

  13. Variable friction secondary seal for face seals

    NASA Technical Reports Server (NTRS)

    Dirusso, E. (Inventor)

    1986-01-01

    Vibration and stability of a primary seal ring is controlled by a secondary seal system. An inflatable bladder which forms a portion of the secondary seal varies the damping applied to this seal ring. The amplitude of vibration of the primary seal ring is sensed with a proximity probe that is connected to a microprocessor in a control system. The bladder pressure is changed by the control system to mitigate any sensed instability or vibration.

  14. Fluid pressure balanced seal

    NASA Technical Reports Server (NTRS)

    Marsh, H. W. (Inventor)

    1966-01-01

    A seal which increases in effectiveness with increasing pressure is presented. The seal's functional capability throughout both static and dynamic operation makes it particularly useful for sealing ball valve ports. Other features of the seal include the ability to seal two opposed surfaces simultaneously, tolerance of small misalignments, tolerance of wide temperature ranges, ability to maintain positive sealing contact under conditions of internal or external pressurization, and ability to conform to slight irregularities in seal or surface contours.

  15. Special Analysis for the Disposal of the Lawrence Livermore National Laboratory EnergyX Macroencapsulated Waste Stream at the Area 5 Radioactive Waste Management Site, Nevada National Security Site, Nye County, Nevada

    SciTech Connect

    Shott, Gregory J.

    2015-06-01

    This special analysis (SA) evaluates whether the Lawrence Livermore National Laboratory (LLNL) EnergyX Macroencapsulated waste stream (B LAMACRONCAP, Revision 1) is suitable for disposal by shallow land burial (SLB) at the Area 5 Radioactive Waste Management Site (RWMS) at the Nevada National Security Site (NNSS). The LLNL EnergyX Macroencapsulated waste stream is macroencapsulated mixed waste generated during research laboratory operations and maintenance (LLNL 2015). The LLNL EnergyX Macroencapsulated waste stream required a special analysis due to tritium (3H), cobalt-60 (60Co), cesium-137 (137Cs), and radium-226 (226Ra) exceeding the NNSS Waste Acceptance Criteria (WAC) Action Levels (U.S. Department of Energy, National Nuclear Security Administration Nevada Field Office [NNSA/NFO] 2015).The results indicate that all performance objectives can be met with disposal of the waste stream in a SLB trench. Addition of the LLNL EnergyX Macroencapsulated inventory slightly increases multiple performance assessment results, with the largest relative increase occurring for the all-pathways annual total effective dose (TED). The maximum mean and 95th percentile 222Rn flux density remain less than the performance objective throughout the compliance period. The LLNL EnergyX Macroencapsulated waste stream is suitable for disposal by SLB at the Area 5 RWMS. The waste stream is recommended for approval without conditions.

  16. Rheological characterization of cementitious grouts used to dispose of intermediate-level radioactive waste by hydrofracturing at Oak Ridge National Laboratory

    SciTech Connect

    McDaniel, E.W.; Moore, J.G.

    1981-01-01

    The hydrofracturing process is a waste disposal process in use at the Oak Ridge National Laboratory for the permanent disposal of locally generated waste solutions. This process is now being modified for use in the disposal of sludge that results from the sodium hydroxide neutralization of acid waste solutions. In this process, the sludges will be slurried in a bentonite clay suspension and mixed with a solids blend of cement and other additives. The amount of dry solids required for each liter of waste slurry will be determined from a rheogram that relates the viscosity of the slurry with the grams per liter recommended for grouts with desirable flow properties. A description of the process and the development of rheograms are included. Data are presented on the use of chemical additives to control the flow properties of grouts.

  17. Film riding seal assembly for turbomachinery

    DOEpatents

    Bidkar, Rahul Anil; Giametta, Andrew Paul; Gibson, Nathan Evan McCurdy; Cleveland, Nicolas Joseph

    2016-06-07

    An aerodynamic seal assembly for a rotary machine includes multiple sealing segments disposed circumferentially intermediate to a stationary housing and a rotor. Each of the segments includes a shoe plate with a forward load-bearing section and an aft load-bearing section configured to generate an aerodynamic force between the shoe plate and the rotor. The shoe plate includes at least one labyrinth teeth facing the rotor and positioned between the forward load-bearing section and the aft load-bearing section. The sealing segment also includes at least one spring connected to a pedestal located about midway of an axial length of the shoe plate and to a stator interface element. Further, the sealing segment includes a rigid segmented secondary seal attached to the stator interface element at one first end and in contact with the pedestal of the shoe plate at one second end.

  18. Shaft seal assembly for high speed and high pressure applications

    NASA Technical Reports Server (NTRS)

    Hadt, W. F.; Ludwig, L. P. (Inventor)

    1979-01-01

    A seal assembly is provided for reducing the escape of fluids from between a housing and a shaft rotably mounted in the housing. The seal assembly comprises a pair of seal rings resiliently connected to each other and disposed in side-by-side relationship. In each seal ring, both the internal bore surface and the radial face which faces away from the other seal ring are provided with a plurality of equi-spaced recesses. The seal faces referred to are located adjacent a seating surface of the housing. Under normal operating conditions, the seal assembly is stationary with respect to the housing, and the recesses generate life, keep the assembly spaced from the rotating shaft and allow slip therebetween. The seal assembly can seize on the shaft, and slip will then occur between the radial faces and the housing.

  19. Implementation of the MARSSIM philosophy to evaluate the remedial status of a radioactive waste disposal site at the Idaho National Engineering and Environmental Laboratory. Multi-Agency Radiation Survey and Site Investigation Manual.

    PubMed

    Schilk, A; Kirkpatrick, J; Dunker, R; Gesell, T

    2000-06-01

    Implementation of the MARSSIM remedial-verification protocol at a radioactive waste disposal site is described in some detail to provide a record of the utility of this process. The selected site was the Stationary Low-Power Reactor No. 1 burial ground at the Idaho National Engineering and Environmental Laboratory. Evaluation was restricted to 137Cs in the uppermost 10 cm of potentially contaminated soils. According to the MARSSIM, this site warranted a "Class 1" designation based on previous remedial activities within the burial ground, its status as a radioactive disposal facility, and the anticipated presence of discrete radioactive particles. Nine survey units within the confines of the burial ground were selected, based primarily on the presence of physical boundaries and disparate histories. Surface scans with 100% coverage were performed using a hand-held plastic scintillator and rate meter with audible output. In situ gamma-ray spectrometry was not used for the individual stationary measurements due to the limited area and proximity of engineered barriers. Instead, individual soil samples were obtained using a standard hand-held coring device. The number of soil samples taken from the background reference area and each survey unit were determined with the MARSSIM protocol, which resulted in a total of 160 (including quality-control samples). Two of the nine regions exhibited elevated radiation levels and the null hypothesis could not be rejected in one survey unit, thereby indicating the need for additional remediation. The MARSSIM process proved to be flexible, scientifically rigorous, and cost effective in this field application. Several modifications to the procedure are discussed and offered as recommendations for enhancement of the MARSSIM. PMID:10832934

  20. Performance testing of large metallic seals

    SciTech Connect

    Leisher, W. B.; Trujillo, A. A.

    1980-01-01

    Containment of radioactive material in spent fuel shipping casks can be achieved if the internal cavity pressure boundary is kept intact under both normal and accident conditions. The major potential boundary weakness is the seal used for cask closure. In an effort to evaluate parameters which influence closure seal performance, an experimental program has been undertaken. This paper describes the program, early results, and test hardware.