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Sample records for llw disposal trenches

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

    Energy Technology Data Exchange (ETDEWEB)

    Yim, M.S. [Harvard School Public Health, Boston, MA (United States); Simonson, S.A. [Massachusetts Institute of Technology, Cambridge, MA (United States)

    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.

  2. Final Design Report for the RH LLW Disposal Facility (RDF) Project

    Energy Technology Data Exchange (ETDEWEB)

    Austad, S. L. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-05-01

    The RH LLW Disposal Facility (RDF) Project was designed by AREVA Federal Services (AFS) and the design process was managed by Battelle Energy Alliance (BEA) for the Department of Energy (DOE). The final design report for the RH LLW Disposal Facility Project is a compilation of the documents and deliverables included in the facility final design.

  3. Final Design Report for the RH LLW Disposal Facility (RDF) Project

    Energy Technology Data Exchange (ETDEWEB)

    Austad, Stephanie Lee [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-09-01

    The RH LLW Disposal Facility (RDF) Project was designed by AREVA Federal Services (AFS) and the design process was managed by Battelle Energy Alliance (BEA) for the Department of Energy (DOE). The final design report for the RH LLW Disposal Facility Project is a compilation of the documents and deliverables included in the facility final design.

  4. Final Design Report for the RH LLW Disposal Facility (RDF) Project

    Energy Technology Data Exchange (ETDEWEB)

    Austad, Stephanie Lee [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-09-01

    The RH LLW Disposal Facility (RDF) Project was designed by AREVA Federal Services (AFS) and the design process was managed by Battelle Energy Alliance (BEA) for the Department of Energy (DOE). The final design report for the RH LLW Disposal Facility Project is a compilation of the documents and deliverables included in the facility final design.

  5. Unreviewed Disposal Question Evaluation: Waste Disposal In Engineered Trench #3

    Energy Technology Data Exchange (ETDEWEB)

    Hamm, L. L.; Smith, F. G. III; Flach, G. P.; Hiergesell, R. A.; Butcher, B. T.

    2013-07-29

    Because Engineered Trench #3 (ET#3) will be placed in the location previously designated for Slit Trench #12 (ST#12), Solid Waste Management (SWM) requested that the Savannah River National Laboratory (SRNL) determine if the ST#12 limits could be employed as surrogate disposal limits for ET#3 operations. SRNL documented in this Unreviewed Disposal Question Evaluation (UDQE) that the use of ST#12 limits as surrogates for the new ET#3 disposal unit will provide reasonable assurance that Department of Energy (DOE) 435.1 performance objectives and measures (USDOE, 1999) will be protected. Therefore new ET#3 inventory limits as determined by a Special Analysis (SA) are not required.

  6. Challenges in establishing LLW disposal capacity: Pennsylvania`s perspective

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    Dornsife, W.P.; Saraka, L.J.

    1989-11-01

    Even though Pennsylvania is host state for the Compact, state implementing legislation was non-existent until early 1988. In February of 1998 Governor Casey signed the Los-Level Radioactive Waste Disposal Act (Act) into law. The Act incorporates three years of Departmental work and interaction with the legislature, a Public Advisory Committee on Low-Level Waste, many interest groups and the general public. It is a comprehensive Act that: provides the Department with broad powers and duties to manage, license and regulate a low-level waste disposal program; requires development phase; and establishes benefits and guarantees for communities affected by the establishment and operation of a low-level waste site. The Department considers that its powers and duties to manage, license and regulate a low-level waste disposal program begins with interpreting the provisions established by the Act. Interpretation will establish how the Department intends to implement its authority. The Department is communicating interpretations through various methods such as regulation, policy, and written or verbal guidance. Interpretations typically require a mix of technical, policy, and social solutions to clarify concepts established by law. This paper identifies select items established by law that require technical solutions. Its purpose is to share some creative approaches for solving unmanageable legislature requirements.

  7. Updated Strategic Assessment of the U.S. NRC Low-Level Radioactive Waste (LLW) Program and the new WCS Commercial Disposal Facility for LLW

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    Kessel, David S.; Kim, Chang-Lak [KEPCO International Nuclear Graduate School, Ulsan (Korea, Republic of)

    2015-05-15

    The purpose of this paper is to review the updated NRC low level radioactive waste regulatory strategy and also present an update on a significant change in the LLW disposal landscape in the U.S., the opening of a new commercial disposal facility, the Texas Compact Waste Facility (CWF) in Andrews, Texas. Operational since spring of 2012, the CWF is owned and licensed by the state of Texas and operated by Waste Control Specialists LLC (WCS). The WCS facility in western Andrews County is the only commercial facility in the United States licensed to dispose of Class A, B and C LLW in the U.S. in the past 40 years. Based on the observation that other suitable sites have been identified such as the Clive, Utah site that meet (almost) all of these criteria it would appear that the first and last factors in our list are the most problematic and it will require a change in the public acceptance and the political posture of states to help solve the national issue of safe and cost-effective LLW disposal.

  8. LLW disposal wasteform preparation in the UK: the role of high force compaction

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, L. F.; Fearnley, I. G. [British Nuclear Fuels Ltd., Sellafield (United Kingdom)

    1991-07-01

    British Nuclear Fuels plc (BNFL) owns and operates the principal UK solid low level radioactive waste (LLW) disposal site. The site is located at Drigg in West Cumbria some 6 km to the south east of BNFL's Sellafield reprocessing complex. Sellafield is the major UK generator of LLW, accounting for about 85% of estimated future arisings of raw (untreated, unpackaged) waste. Non-Sellafield consignors to the Drigg site include other BNFL production establishments, nuclear power stations, sites of UKAEA, Ministry of Defence facilities, hospitals, universities, radioisotope production sites and various other industrial organisations. In September 1987, BNFL announced a major upgrade of operations at the Drigg site aimed at improving management practices, the efficiency of space utilisation and enhancing the visual impact of disposal operations. During 1989 a review of plans for compaction and containerisation of Sellafield waste identified that residual voidage in ISO freight containers could be significant even after the introduction of compaction. Subsequent studies which examined a range of compaction and packaging options concluded that the preferred scheme centred on the use of high force compaction (HFC) of compactable waste, and grouting to take up readily accessible voidage in the wasteform. The paper describes the emergence of high force compaction as the preferred scheme for wasteform preparation and subsequent benefits against the background of the overall development of Low Level Waste disposal operations at Drigg.

  9. A process for establishing a financial assurance plan for LLW disposal facilities

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    Smith, P. [EG and G Idaho, Inc., Idaho Falls, ID (United States). National Low-Level Waste Management Program

    1993-04-01

    This document describes a process by which an effective financial assurance program can be developed for new low-level radioactive waste (LLW) disposal facilities. The report identifies examples of activities that might cause financial losses and the types of losses they might create, discusses mechanisms that could be used to quantify and ensure against the various types of potential losses identified and describes a decision process to formulate a financial assurance program that takes into account the characteristics of both the potential losses and available mechanisms. A sample application of the concepts described in the report is provided.

  10. Incremental Risks of Transporting NARM to the LLW Disposal Facility at Hanford

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    Weiner, R.F.

    1999-02-23

    This study models the incremental radiological risk of transporting NARM to the Hanford commercial LLW facility, both for incident-free transportation and for possible transportation accidents, compared with the radiological risk of transporting LLW to that facility. Transportation routes are modeled using HIGHWAY 3.1 and risks are modeled using RADTRAN 4. Both annual population doses and risks, and annual average individual doses and risks are reported. Three routes to the Hanford site were modeled from Albany, OR, from Coeur d'Alene, ID (called the Spokane route), and from Seattle, WA. Conservative estimates are used in the RADTRAN inputs, and RADTRAN itself is conservative.

  11. Integration of US Department of Energy contractor installations for the purpose of optimizing treatment, storage, and disposal of low-level radioactive waste (LLW)

    Energy Technology Data Exchange (ETDEWEB)

    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.

  12. Disposal of Low-Level Waste (LLW) at the Nevada National Security Site (NNSS)

    Energy Technology Data Exchange (ETDEWEB)

    none, none

    2014-05-14

    DOE Office of Environmental Management presentation at the 2014 Annual Meeting of the National Transportation Stakeholders Forum on the disposal of low-level waste at the Nevada National Security Site.

  13. UNREVIEWED DISPOSAL QUESTION EVALUATION: CENTER SLIT TRENCHES ONE THROUGH FIVE OPERATIONAL COVERS REANALYSIS

    Energy Technology Data Exchange (ETDEWEB)

    Smith, F.; Swingle, R.

    2011-05-26

    Operational inventory limits for the disposal of solid low-level waste in Slit Trenches 1-7 were established by the Special Analysis (SA) performed by Collard and Hamm (2008). To determine disposal limits for the Slit Trenches, the SA followed the methodology used in the 2008 PA (WSRC, 2008) which assumed that the inventories in each trench were instantaneously placed in 12/1995, which is the date when SLIT1 began operation. The 2008 SA analyzed the impact from placing storm-water runoff covers simultaneously over Slit Trenches 1-7 at 5, 10 and 15 years after the inventory was introduced. To include a measure of conservatism in the limits, the lowest of the limits calculated for any storm-water runoff cover placement time or that calculated in the original 2008 PA was chosen as the operational limit for each radionuclide. Through the availability of funding provided by the American Recovery and Reinvestment Act (ARRA), storm-water runoff covers were placed over Slit Trenches 1-5 in December 2010. SRNL was requested to perform a UDQE for this accelerated action. Table 1 below lists the operational dates for Slit Trenches 1-5 and the time elapsed between when the first waste package was disposed in each Slit Trench and when the storm-water runoff covers were placed. As shown in Table 1, SLIT1 was covered 15.0 years after the date of the first waste package disposal. SLIT2 was covered 9.2 years after the date of the first waste package disposal in SLIT2 which falls within the window of {+-} 1.0 year within which the 2008 SA cover time analysis was assumed to be valid (Crowley and Butcher, 2008). Therefore, the analysis of SLIT1 and SLIT2 in the 2008 SA is considered adequate. However, the cover timings for SLIT3, SLIT4 and SLIT5 are from 2.2 to 1.6 years beyond the nearest cover time of 5 years assumed in the 2008 SA analysis and fall outside of the acceptable one-year margin. Therefore, an additional study was conducted by Collard et al. (2011) that assessed the

  14. Compliance matrix for the mixed waste disposal facilities, trenches 31 and 34, burial ground 218-W-5. Revision 2

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, K.D.

    1995-05-03

    This document provides a listing of applicable regulatory requirements to the Mixed Waste Disposal trenches. After the listing of regulations to be followed is a listing of documents that show how the regulations are being implemented and followed for the Mixed Waste trenches.

  15. Nuclear criticality safety assessment of the low level radioactive waste disposal facility trenches

    Energy Technology Data Exchange (ETDEWEB)

    Kahook, S.D.

    1994-04-01

    Results of the analyses performed to evaluate the possibility of nuclear criticality in the Low Level Radioactive Waste Disposal Facility (LLRWDF) trenches are documented in this report. The studies presented in this document are limited to assessment of the possibility of criticality due to existing conditions in the LLRWDF. This document does not propose nor set limits for enriched uranium (EU) burial in the LLRWDF and is not a nuclear criticality safety evaluation nor analysis. The calculations presented in the report are Level 2 calculations as defined by the E7 Procedure 2.31, Engineering Calculations.

  16. Corrective action plan for CAU No. 404: Roller Coaster Sewage Lagoons and North Disposal Trench, Tonopah Test Range

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-07-01

    This Corrective Action Plan (CAP) provides the selected corrective action alternative and proposes the closure implementation methodology for the Roller Coaster Sewage Lagoons and North Disposal Trench Corrective Action Unit (CAU) No. 404. The site is located on the Tonopah Test Range. CAU 404 consists of two Corrective Action Sites (CAS): the Roller Coaster Lagoons (CAS No TA-03-001-TA-RC) and the North Disposal Trench (CAS No TA-21-001-TA-RC). A site map of the lagoons and trench is provided. The Roller Coaster Sewage Lagoons are comprised of two unlined lagoons that received liquid sanitary waste in 1963 from the Operation Roller Coaster Man Camp and debris from subsequent construction and range cleanup activities. The North Disposal Trench was excavated in approximately 1963 and received solid waste and debris from the man camp and subsequent construction and range cleanup activities. A small hydrocarbon spill occurred during the 1995 Voluntary Corrective Action (VCA) activities in an area associated with the North Disposal Trench CAS.

  17. SPECIAL ANALYSIS FOR SLIT TRENCH DISPOSAL OF THE REACTOR PROCESS HEAT EXCHANGERS

    Energy Technology Data Exchange (ETDEWEB)

    Hamm, L.; Collard, L.; Aleman, S.; Gorensek, M.; Butcher, T.

    2012-06-18

    The Savannah River National Laboratory (SRNL), in response to a request from Solid Waste Management (SWM), conducted a Special Analysis (SA) to evaluate the performance of nineteen heat exchangers that are to be disposed in the E-Area low level waste facility Slit Trench 9 (ST 9). Although these nineteen heat exchangers were never decontaminated, the majority of the radionuclides in the heat exchanger inventory list were determined to be acceptable for burial because they are less than the 'generic' waste form inventory limits given in the 2008 Performance Assessment (PA) (WSRC, 2008). However, as generic waste, the H-3 and C-14 inventories resulted in unacceptable sum-of-fractions (SOFs). Initial scoping analyses performed by SRNL indicated that if alterations were made to certain external nozzles to mitigate various potential leak paths, acceptable SOFs could be achieved through the use of a 'Special' waste form. This SA provides the technical basis for this new 'Special' waste form and provides the inventory limits for H-3 and C-14 for these nineteen heat exchangers such that the nineteen heat exchangers can be disposed in ST 9. This 'Special' waste form is limited to these nineteen heat exchangers in ST 9 and applies for H-3 and C-14, which are designated as H-3X and C-14X, respectively. The SA follows the same methodology used in the 2008 PA and the 2008 SA except for the modeling enhancements noted below. Infiltration rates above the heat exchangers are identical to those used in the 2008 PA; however, flow through the heat exchangers is unique. Because it is unknown exactly how sealed heat exchanger openings will perform and how surface and embedded contaminants will be released, multiple base cases or scenarios were established to investigate a set of performances. Each scenario consists of flow options (based on the performance of sealed openings) and a near-field release of contaminants (based on corrosion and

  18. RH-LLW Disposal Facility Project CD-2/3 to Design/Build Proposal Reconciliation Report

    Energy Technology Data Exchange (ETDEWEB)

    Annette L. Schafer

    2012-06-01

    A reconciliation plan was developed and implemented to address potential gaps and responses to gaps between the design/build vendor proposals and the Critical Decision-2/3 approval request package for the Remote-Handled Low Level Waste Disposal Facility Project. The plan and results of the plan implementation included development of a reconciliation team comprised of subject matter experts from Battelle Energy Alliance and the Department of Energy Idaho Operations Office, identification of reconciliation questions, reconciliation by the team, identification of unresolved/remaining issues, and identification of follow-up actions and subsequent approvals of responses. The plan addressed the potential for gaps to exist in the following areas: • Department of Energy Order 435.1, “Radioactive Waste Management,” requirements, including the performance assessment, composite analysis, monitoring plan, performance assessment/composite analysis maintenance plan, and closure plan • Environmental assessment supporting the National Environmental Policy Act • Nuclear safety • Safeguards and security • Emplacement operations • Requirements for commissioning • General project implementation. The reconciliation plan and results of the plan implementation are provided in a business-sensitive project file. This report provides the reconciliation plan and non-business sensitive summary responses to identified gaps.

  19. Modeling the Hydrogeochemical Transport of Radionuclides through Engineered Barriers System in the Proposed LLW Disposal Site of Taiwan - 12082

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Wen-Sheng [Hydrotech Research Institute, National Taiwan University, Taipei, Taiwan (China); Liu, Chen-Wuing; Tsao, Jui-Hsuan [Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei, Taiwan (China); Li, Ming-Hsu [Institute of Hydrological and Oceanic Sciences, National Central University, Jhongli, Taiwan (China)

    2012-07-01

    A proposed site for final disposal of low-level radioactive waste located in Daren Township of Taitung County along the southeastern coast has been on the selected list in Taiwan. The geology of the Daren site consists of argillite and meta-sedimentary rocks. A mined cavern design with a tunnel system of 500 m below the surface is proposed. Concrete is used as the main confinement material for the engineered barrier. To investigate the hydrogeochemical transport of radionuclides through engineered barriers system, HYDROGEOCHEM5.0 model was applied to simulate the complex chemical interactions among radionuclides, the cement minerals of the concrete, groundwater flow, and transport in the proposed site. The simulation results showed that the engineered barriers system with the side ditch efficiently drained the ground water and lowered the concentration of the concrete degradation induced species (e.g., hydrogen ion, sulfate, and chloride). The velocity of groundwater observed at side ditch gradually decreased with time due to the fouling of pore space by the mineral formation of ettringite and thaumasite. The short half-life of Co-60, Sr-90 and Cs-137 significantly reduced the concentrations, whereas the long half-life of I-129(1.57x10{sup 7} years) and Am-241(432 years) remain stable concentrations at the interface of waste canister and concrete barrier after 300 years. The mineral saturation index (SI) was much less than zero due to the low aqueous concentration of radionuclide, so that the precipitation formation of Co-60, Sr-90, I-129, Cs-137 and Am-241 related minerals were not found. The effect of adsorption/desorption (i.e., surface complexation model) could be a crucial geochemical mechanism for the modeling of liquid-solid phase behavior of radionuclide in geochemically dynamic environments. Moreover, the development of advanced numerical models that are coupled with hydrogeochemical transport and dose assessment of radionuclide is required in the future

  20. LLW Dumpster study: Task 009

    Energy Technology Data Exchange (ETDEWEB)

    Frye, J.A. [Thompson (T.K.), Inc., White Rock, NM (United States)

    1989-08-01

    Over a span of several years, the public has reported visible leakage emanating from ten cubic yard Dumpsters used to transport Low Level Radioactive Wastes (LLW) from LANL generation sites to the disposal site at TA-54, Area G. The purpose of this study was to: Investigate probable causes of leakages, Inspect existing Dumpsters in the fields Propose immediate short-range solutions to the problem, and Propose long-range solutions based on predicted future requirements. Field investigations indicated that LLW is handled carefully and professional at the individual generation sites and again during pick-up delivery, and disposal at TA-54. It was also apparent, however, that Dumpsters not designed for LLW service are used to store this radioactive material for extended time periods while being subjected to the full range of Northern New Mexico weather conditions. All Dumpsters inspected had 1/8 in to 2 in gaps in their closures (loading doors and discharge ramps) through which driving rain or melting snow could easily enter. Seven Dumpsters were located outside secure areas. No cases of actual contamination were discovered, only the appearance of contamination i.e. the dripping of collected rainwater or melting ice and snow from Dumpsters being transported over public roads.

  1. LLW Forum meeting report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-08-01

    This report summarizes the Low-Level Radioactive Waste Forum (LLW Forum) meeting on May 29 through May 31, 1996.The LLW Forum is an association of state and compact representatives, appointed by governors and compact commissions, established to facilitate state and compact implementation of the Low-Level Waste Policy Act of 1980 and the Low-Level Radioactive Waste Policy Amendments Act of 1985 and to promote the objectives of low-level radioactive waste regional compacts. The LLW forum provides an opportunity for state and compact officials to share information with one another and to exchange views with officials of federal agencies and other interested parties.

  2. Preliminary design of a biological treatment facility for trench water from a low-level radioactive waste disposal area at West Valley, New York

    Energy Technology Data Exchange (ETDEWEB)

    Rosten, R.; Malkumus, D. [Pacific Nuclear, Inc. (United States); Sonntag, T. [New York State Energy Research and Development Authority, NY (United States); Sundquist, J. [Ecology and Environment, Inc. (United States)

    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.

  3. Corrective Action Investigation Plan for Corrective Action Unit 410: Waste Disposal Trenches, Tonopah Test Range, Nevada, Revision 0 (includes ROTCs 1, 2, and 3)

    Energy Technology Data Exchange (ETDEWEB)

    NNSA/NV

    2002-07-16

    This Corrective Action Investigation Plan contains the U.S. Department of Energy, National Nuclear Security Administration Nevada Operations Office's approach to collect the data necessary to evaluate corrective action alternatives appropriate for the closure of Corrective Action Unit (CAU) 410 under the Federal Facility Agreement and Consent Order. Corrective Action Unit 410 is located on the Tonopah Test Range (TTR), which is included in the Nevada Test and Training Range (formerly the Nellis Air Force Range) approximately 140 miles northwest of Las Vegas, Nevada. This CAU is comprised of five Corrective Action Sites (CASs): TA-19-002-TAB2, Debris Mound; TA-21-003-TANL, Disposal Trench; TA-21-002-TAAL, Disposal Trench; 09-21-001-TA09, Disposal Trenches; 03-19-001, Waste Disposal Site. This CAU is being investigated because contaminants may be present in concentrations that could potentially pose a threat to human health and/or the environment, and waste may have been disposed of with out appropriate controls. Four out of five of these CASs are the result of weapons testing and disposal activities at the TTR, and they are grouped together for site closure based on the similarity of the sites (waste disposal sites and trenches). The fifth CAS, CAS 03-19-001, is a hydrocarbon spill related to activities in the area. This site is grouped with this CAU because of the location (TTR). Based on historical documentation and process know-ledge, vertical and lateral migration routes are possible for all CASs. Migration of contaminants may have occurred through transport by infiltration of precipitation through surface soil which serves as a driving force for downward migration of contaminants. Land-use scenarios limit future use of these CASs to industrial activities. The suspected contaminants of potential concern which have been identified are volatile organic compounds; semivolatile organic compounds; high explosives; radiological constituents including depleted

  4. LLW Forum meeting report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1991-12-31

    This document reports the details of the Quarterly Meeting of the Low- Level Radioactive Waste Forum held in San Diego, California during January 23-25, 1991. Topics discussed include: State and Compact Progress Reports; Legal Updates; Update on Technical Assistance; Advanced Notice of Proposed Rulemaking Regarding Surcharge Rebates; Update on TCC Activities; NRC Update; Disposal of Commercial Mixed Waste; Update on EPA Activities; ACNW Working Group on Mixed Waste; National Profile on Mixed Waste; Commercial Perspective on Mixed Waste; Update on DOT Activities; Source Terms; Materials and Waste; Storage: and Waste Acceptance Criteria and Packaging.

  5. Request for interim approval to operate Trench 94 of the 218-E-12B Burial Ground as a chemical waste landfill for disposal of polychlorinated biphenyl waste in submarine reactor compartments. Revision 2

    Energy Technology Data Exchange (ETDEWEB)

    Cummins, G.D.

    1994-06-01

    This request is submitted to seek interim approval to operate a Toxic Substances Control Act (TSCA) of 1976 chemical waste landfill for the disposal of polychlorinated biphenyl (PCB) waste. Operation of a chemical waste landfill for disposal of PCB waste is subject to the TSCA regulations of 40 CFR 761. Interim approval is requested for a period not to exceed 5 years from the date of approval. This request covers only the disposal of small 10 quantities of solid PCB waste contained in decommissioned, defueled submarine reactor compartments (SRC). In addition, the request applies only to disposal 12 of this waste in Trench 94 of the 218-E-12B Burial Ground (Trench 94) in the 13 200 East Area of the US Department of Energy`s (DOE) Hanford Facility. Disposal of this waste will be conducted in accordance with the Compliance 15 Agreement (Appendix H) between the DOE Richland Operations Office (DOE-RL) and 16 the US Environmental Protection Agency (EPA), Region 10. During the 5-year interim approval period, the DOE-RL will submit an application seeking final 18 approval for operation of Trench 94 as a chemical waste landfill, including 19 any necessary waivers, and also will seek a final dangerous waste permit from 20 the Washington State Department of Ecology (Ecology) for disposal of lead 21 shielding contained in the SRCS.

  6. Remote-Handled Low-Level Waste (RHLLW) Disposal Project Code of Record

    Energy Technology Data Exchange (ETDEWEB)

    S.L. Austad, P.E.; L.E. Guillen, P.E.; C. W. McKnight, P.E.; D. S. Ferguson, P.E.

    2010-10-01

    The Remote-Handled Low-Level Waste Disposal Project addresses an anticipated shortfall in remote-handled LLW disposal capability following cessation of operations at the existing facility, which will continue until it is full or until it must be closed in preparation for final remediation of the Subsurface Disposal Area (approximately at the end of fiscal year 2015). Development of a new onsite disposal facility, the highest ranked alternative, will provide necessary remote handled LLW disposal capability and will ensure continuity of operations that generate remote-handled LLW. This report documents the Code of Record for design of a new LLW disposal capability.

  7. The use of NUREGs 1199 and 1200 in the Illinois LLW licensing program

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    Klinger, J.G.; Harmon, D.F. [Illinois Dept. of Nuclear Safety, Springfield, IL (United States). Licensing Div.

    1991-12-31

    This paper will describe how the LLW licensing staff of the Illinois Department of Nuclear Safety used NRC`s NUREG 1199, NUREG 1200, NUREG 1300 and Regulatory Guide 4.18 in its licensing program for reviewing and evaluating a LLW disposal facility license application. The paper will discuss how Illinois guidance documents were prepared based on modifications made to these NRC documents which were necessary to take into account site and facility specific considerations, as well as changes required by Illinois statutes and regulatory codes. The paper will review the recent revisions (January 1991) to NUREG 1199 and 1200 and the importance of these revisions. The paper will also discuss recommended modifications to these NRC documents and provide an update on the status of the Department`s review and evaluation of an application for a license to site, construct and operate a LLW disposal facility in Illinois.

  8. Technical issues associated with in situ vitrification of the INEL Subsurface Disposal Area. Volume 3, Application of technical issues to the TRU-contaminated pits and trenches

    Energy Technology Data Exchange (ETDEWEB)

    Stoots, C.M.; Bates, S.O.; Callow, R.A.; Campbell, K.A.; Farnsworth, R.K.; Krisman, G.K.; McKellar, M.G.; Nickelson, D.F.; Slater, C.E.

    1992-07-01

    In situ vitrification (ISV) has been identified as an alternative technology for remediation of the acid pit and transuranic pits and trenches (TRU-PTs) at the Idaho National Engineering Laboratory (INEL) Subsurface Disposal Area (SDA). However, a number of technical issues must be resolved before ISV can be considered applicable to these waste sites. To assist in the ISV technology evaluation, an ISV Steering Committee was formed to identify, prioritize, and develop closure roadmaps for technical issues lated with ISV application at the SDA. The activities of the ISV Steering Committee are summarized in a three-volume report. Volume I identifies the systematic approach used to identify and prioritize the ISV technical issues and briefly discusses the methodology that will be employed to resolve these issues. Volumes 2 and 3 discuss each technical issue in greater detail and suggest specific closure roadmaps to be used in resolving technical issues associated with ISV at the SDA Acid Pit and TRU-PTS, respectively. The three-volume report is a working document that will be updated as necessary to reflect current evaluation strategy for the ISV technology. This is Volume 3.

  9. Preliminary low-level waste feed definition guidance - LLW pretreatment interface

    Energy Technology Data Exchange (ETDEWEB)

    Shade, J.W.; Connor, J.M.; Hendrickson, D.W.; Powell, W.J.; Watrous, R.A.

    1995-02-01

    The document describes limits for key constituents in the LLW feed, and the bases for these limits. The potential variability in the stream is then estimated and compared to the limits. Approaches for accomodating uncertainty in feed inventory, processing strategies, and process design (melter and disposal system) are discussed. Finally, regulatory constraints are briefly addressed.

  10. Selection of models to calculate the LLW source term

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, T.M. (Brookhaven National Lab., Upton, NY (United States))

    1991-10-01

    Performance assessment of a LLW disposal facility begins with an estimation of the rate at which radionuclides migrate out of the facility (i.e., the source term). The focus of this work is to develop a methodology for calculating the source term. In general, the source term is influenced by the radionuclide inventory, the wasteforms and containers used to dispose of the inventory, and the physical processes that lead to release from the facility (fluid flow, container degradation, wasteform leaching, and radionuclide transport). In turn, many of these physical processes are influenced by the design of the disposal facility (e.g., infiltration of water). The complexity of the problem and the absence of appropriate data prevent development of an entirely mechanistic representation of radionuclide release from a disposal facility. Typically, a number of assumptions, based on knowledge of the disposal system, are used to simplify the problem. This document provides a brief overview of disposal practices and reviews existing source term models as background for selecting appropriate models for estimating the source term. The selection rationale and the mathematical details of the models are presented. Finally, guidance is presented for combining the inventory data with appropriate mechanisms describing release from the disposal facility. 44 refs., 6 figs., 1 tab.

  11. LLW Notes, Volume 12, Number 3

    Energy Technology Data Exchange (ETDEWEB)

    Norris, C.; Brown, H. [eds.; Colsant, J.; Lovinger, T.; Scheele, L.; Shaker, M.A.

    1997-03-01

    Contents include articles entitled: California DHS sues US Interior Department to compel land transfer; LLW Forum holds winter meeting; LLW Forum waste information working group meets; LLW Forum regulatory issues discussion group meets; Envirocare investigation transferred to feds; Host state TCC meets in Laughlin, Nevada; BLM to require new permit for California site testing; Federal agencies and committees; Pena sworn in as Energy Secretary, Grumbly departs DOE; U.S. Supreme Court tackles property rights issues; GAO to study DOI`s actions; Congress scrutinizes FY `98 budget requests; and Senate committee passes high-level waste bill: Clinton threatens to veto.

  12. LLW notes, Vol. 11, No. 2

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    `LLW Notes` is distributed by Afton Associates, Inc. to Low-Level Radioactive Waste Forum Participants and other state, and compact officials identified by those Participants to receive LLW Notes. The Low-Level Radioactive Waste Forum (LLW Forum) is an association of state and compact representatives, appointed by governors and compact commissions, established to facilitate state and compact implementation of the Low-Level Radioactive Waste Policy Act of 1980 and the Low-Level Radioactive Waste Policy amendments Act of 1985 and to promote the objectives of low-level radioactive waste regional compacts. The LLW Forum provides an opportunity for state and compact officials to share information with one another and to exchange views with officials of federal agencies and other interested parties.

  13. Role of trench caps in the shallow land burial of low level wastes

    Science.gov (United States)

    Mezga, L. J.

    1984-05-01

    Experience dating back to the early 1940s clearly documents the importance of isolating waste disposed of by shallow land burial from the biosphere. While no significant threat to the health and safety of the public has occurred to data, poor facility siting and/or design has resulted in a number of sites failing to perform as predicted or in an acceptable manner. The trench cap may be the single most important component of the LLW disposal system. It must effectively isolate the waste from the biosphere by controlling infiltration, gaseous emissions, and biointrusions. At the same time, a number of other forces (i.e., erosion and subsidence) are acting to destroy its integrity. Results of experiments and operational experience to date indicate that while one design feature may be effective at controlling one problem (e.g., cobble gravel effectively controls biointrusion), that same design feature may be ineffective or actually exacerbate another problem (e.g., cobble gravel may allow increased infiltration rates). Therefore, trench cap design must evaluate the systems effects of the various options either using intuitive methods as is currently the case or by using mathematical models which are currently being developed and validated.

  14. Greater-than-Class C low-level radioactive waste characterization. Appendix E-2: Mixed GTCC LLW assessment

    Energy Technology Data Exchange (ETDEWEB)

    Kirner, N.P. [Ebasco Environmental, Idaho Falls, ID (United States)

    1994-09-01

    Mixed greater-than-Class C low-level radioactive waste (mixed GTCC LLW) is waste that combines two characteristics: it is radioactive, and it is hazardous. This report uses information compiled from Greater-Than-Class C Low-Level Radioactive Waste Characterization: Estimated Volumes, Radionuclide Activities, and Other Characteristics (DOE/LLW 1 14, Revision 1), and applies it to the question of how much and what types of mixed GTCC LLW are generated and are likely to require disposal in facilities jointly regulated by the DOE and the NRC. The report describes how to classify a RCRA hazardous waste, and then applies that classification process to the 41 GTCC LLW waste types identified in the DOE/LLW-114 (Revision 1). Of the 41 GTCC LLW categories identified, only six were identified in this study as potentially requiring regulation as hazardous waste under RCRA. These wastes can be combined into the following three groups: fuel-in decontamination resins, organic liquids, and process waste consisting of lead scrap/shielding from a sealed source manufacturer. For the base case, no mixed GTCC LLW is expected from nuclear utilities or sealed source licensees, whereas only 177 ml of mixed GTCC LLW are expected to be produced by other generators through the year 2035. This relatively small volume represents approximately 40% of the base case estimate for GTCC wastes from other generators. For these other generators, volume estimates for mixed GTCC LLW ranged from less than 1 m{sup 3} to 187 m{sup 3}, depending on assumptions and treatments applied to the wastes.

  15. Closure Report for Corrective Action Unit 139: Waste Disposal Sites, Nevada Test Site, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    NSTec Environmental Restoration

    2009-07-31

    Corrective Action Unit (CAU) 139 is identified in the Federal Facility Agreement and Consent Order (FFACO) as 'Waste Disposal Sites' and consists of the following seven Corrective Action Sites (CASs), located in Areas 3, 4, 6, and 9 of the Nevada Test Site: CAS 03-35-01, Burn Pit; CAS 04-08-02, Waste Disposal Site; CAS 04-99-01, Contaminated Surface Debris; CAS 06-19-02, Waste Disposal Site/Burn Pit; CAS 06-19-03, Waste Disposal Trenches; CAS 09-23-01, Area 9 Gravel Gertie; and CAS 09-34-01, Underground Detection Station. Closure activities were conducted from December 2008 to April 2009 according to the FFACO (1996, as amended February 2008) and the Corrective Action Plan for CAU 139 (U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office, 2007b). The corrective action alternatives included No Further Action, Clean Closure, and Closure in Place with Administrative Controls. Closure activities are summarized. CAU 139, 'Waste Disposal Sites,' consists of seven CASs in Areas 3, 4, 6, and 9 of the NTS. The closure alternatives included No Further Action, Clean Closure, and Closure in Place with Administrative Controls. This CR provides a summary of completed closure activities, documentation of waste disposal, and confirmation that remediation goals were met. The following site closure activities were performed at CAU 139 as documented in this CR: (1) At CAS 03-35-01, Burn Pit, soil and debris were removed and disposed as LLW, and debris was removed and disposed as sanitary waste. (2) At CAS 04-08-02, Waste Disposal Site, an administrative UR was implemented. No postings or post-closure monitoring are required. (3) At CAS 04-99-01, Contaminated Surface Debris, soil and debris were removed and disposed as LLW, and debris was removed and disposed as sanitary waste. (4) At CAS 06-19-02, Waste Disposal Site/Burn Pit, no work was performed. (5) At CAS 06-19-03, Waste Disposal Trenches, a native soil cover was installed

  16. 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

    Energy Technology Data Exchange (ETDEWEB)

    Sundquist, J.A.; Gillings, J.C. [Ecology and Environment, Inc. (United States); Sonntag, T.L. [New York State Energy Research and Development Authority (United States); Denault, R.P. [Pacific Nuclear, Inc. (United States)

    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.

  17. Comparison of low-level waste disposal programs of DOE and selected international countries

    Energy Technology Data Exchange (ETDEWEB)

    Meagher, B.G. [Lockheed Idaho Technologies Co., Idaho Falls, ID (United States); Cole, L.T. [Cole and Associates (United States)

    1996-06-01

    The purpose of this report is to examine and compare the approaches and practices of selected countries for disposal of low-level radioactive waste (LLW) with those of the US Department of Energy (DOE). The report addresses the programs for disposing of wastes into engineered LLW disposal facilities and is not intended to address in-situ options and practices associated with environmental restoration activities or the management of mill tailings and mixed LLW. The countries chosen for comparison are France, Sweden, Canada, and the United Kingdom. The countries were selected as typical examples of the LLW programs which have evolved under differing technical constraints, regulatory requirements, and political/social systems. France was the first country to demonstrate use of engineered structure-type disposal facilities. The UK has been actively disposing of LLW since 1959. Sweden has been disposing of LLW since 1983 in an intermediate-depth disposal facility rather than a near-surface disposal facility. To date, Canada has been storing its LLW but will soon begin operation of Canada`s first demonstration LLW disposal facility.

  18. Remote-Handled Low-Level Waste Disposal Project Code of Record

    Energy Technology Data Exchange (ETDEWEB)

    S.L. Austad, P.E.; L.E. Guillen, P.E.; C. W. McKnight, P.E.; D. S. Ferguson, P.E.

    2012-06-01

    The Remote-Handled Low-Level Waste (LLW) Disposal Project addresses an anticipated shortfall in remote-handled LLW disposal capability following cessation of operations at the existing facility, which will continue until it is full or until it must be closed in preparation for final remediation of the Subsurface Disposal Area (approximately at the end of Fiscal Year 2017). Development of a new onsite disposal facility will provide necessary remote-handled LLW disposal capability and will ensure continuity of operations that generate remote-handled LLW. This report documents the Code of Record for design of a new LLW disposal capability. The report is owned by the Design Authority, who can authorize revisions and exceptions. This report will be retained for the lifetime of the facility.

  19. Remote-Handled Low-Level Waste Disposal Project Code of Record

    Energy Technology Data Exchange (ETDEWEB)

    S.L. Austad, P.E.; L.E. Guillen, P.E.; C. W. McKnight, P.E.; D. S. Ferguson, P.E.

    2012-04-01

    The Remote-Handled Low-Level Waste (LLW) Disposal Project addresses an anticipated shortfall in remote-handled LLW disposal capability following cessation of operations at the existing facility, which will continue until it is full or until it must be closed in preparation for final remediation of the Subsurface Disposal Area (approximately at the end of Fiscal Year 2017). Development of a new onsite disposal facility will provide necessary remote-handled LLW disposal capability and will ensure continuity of operations that generate remote-handled LLW. This report documents the Code of Record for design of a new LLW disposal capability. The report is owned by the Design Authority, who can authorize revisions and exceptions. This report will be retained for the lifetime of the facility.

  20. Remote-Handled Low-Level Waste Disposal Project Code of Record

    Energy Technology Data Exchange (ETDEWEB)

    Austad, S. L. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Guillen, L. E. [Idaho National Lab. (INL), Idaho Falls, ID (United States); McKnight, C. W. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Ferguson, D. S. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-04-01

    The Remote-Handled Low-Level Waste (LLW) Disposal Project addresses an anticipated shortfall in remote-handled LLW disposal capability following cessation of operations at the existing facility, which will continue until it is full or until it must be closed in preparation for final remediation of the Subsurface Disposal Area (approximately at the end of Fiscal Year 2017). Development of a new onsite disposal facility will provide necessary remote-handled LLW disposal capability and will ensure continuity of operations that generate remote-handled LLW. This report documents the Code of Record for design of a new LLW disposal capability. The report is owned by the Design Authority, who can authorize revisions and exceptions. This report will be retained for the lifetime of the facility.

  1. Remote-Handled Low-Level Waste Disposal Project Code of Record

    Energy Technology Data Exchange (ETDEWEB)

    S.L. Austad, P.E.; L.E. Guillen, P.E.; C. W. McKnight, P.E.; D. S. Ferguson, P.E.

    2014-06-01

    The Remote-Handled Low-Level Waste (LLW) Disposal Project addresses an anticipated shortfall in remote-handled LLW disposal capability following cessation of operations at the existing facility, which will continue until it is full or until it must be closed in preparation for final remediation of the Subsurface Disposal Area (approximately at the end of Fiscal Year 2017). Development of a new onsite disposal facility will provide necessary remote-handled LLW disposal capability and will ensure continuity of operations that generate remote-handled LLW. This report documents the Code of Record for design of a new LLW disposal capability. The report is owned by the Design Authority, who can authorize revisions and exceptions. This report will be retained for the lifetime of the facility.

  2. Remote-Handled Low-Level Waste Disposal Project Code of Record

    Energy Technology Data Exchange (ETDEWEB)

    S.L. Austad, P.E.; L.E. Guillen, P.E.; C. W. McKnight, P.E.; D. S. Ferguson, P.E.

    2011-04-01

    The Remote-Handled Low-Level Waste (LLW) Disposal Project addresses an anticipated shortfall in remote-handled LLW disposal capability following cessation of operations at the existing facility, which will continue until it is full or until it must be closed in preparation for final remediation of the Subsurface Disposal Area (approximately at the end of Fiscal Year 2017). Development of a new onsite disposal facility, the highest ranked alternative, will provide necessary remote-handled LLW disposal capability and will ensure continuity of operations that generate remote-handled LLW. This report documents the Code of Record for design of a new LLW disposal capability. The report is owned by the Design Authority, who can authorize revisions and exceptions. This report will be retained for the lifetime of the facility.

  3. Remote-Handled Low-Level Waste Disposal Project Code of Record

    Energy Technology Data Exchange (ETDEWEB)

    S.L. Austad, P.E.; L.E. Guillen, P.E.; C. W. McKnight, P.E.; D. S. Ferguson, P.E.

    2011-01-01

    The Remote-Handled Low-Level Waste (LLW) Disposal Project addresses an anticipated shortfall in remote-handled LLW disposal capability following cessation of operations at the existing facility, which will continue until it is full or until it must be closed in preparation for final remediation of the Subsurface Disposal Area (approximately at the end of Fiscal Year 2017). Development of a new onsite disposal facility, the highest ranked alternative, will provide necessary remote-handled LLW disposal capability and will ensure continuity of operations that generate remote-handled LLW. This report documents the Code of Record for design of a new LLW disposal capability. The report is owned by the Design Authority, who can authorize revisions and exceptions. This report will be retained for the lifetime of the facility.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  5. Department of Energy low-level radioactive waste disposal concepts

    Energy Technology Data Exchange (ETDEWEB)

    Ozaki, C.; Page, L.; Morreale, B.; Owens, C.

    1990-01-01

    The Department of Energy (DOE) manages its low-level waste (LLW), regulated by DOE Order 5820.2A by using an overall systems approach. This systems approach provides an improved and consistent management system for all DOE LLW waste, from generation to disposal. This paper outlines six basic disposal concepts used in the systems approach, discusses issues associated with each of the concepts, and outlines both present and future disposal concepts used at six DOE sites. 3 refs., 9 figs.

  6. Low-level radioactive waste (LLW) management at the Nevada Test Site (NTS)

    Energy Technology Data Exchange (ETDEWEB)

    Becker, B.D. [Bechtel Nevada, Inc., Las Vegas, NV (United States); Gertz, C.P.; Clayton, W.A.; Crowe, B.M. [Dept. of Energy, Las Vegas, NV (United States). Nevada Operations Office

    1998-12-31

    In 1978, the Department of Energy, Nevada Operations Office (DOE/NV), established a managed LLW disposal project at the Nevada Test Site (NTS). Two, sites which were already accepting limited amounts of on-site generated waste for disposal and off-site generated Transuranic Waste for interim storage, were selected to house the disposal facilities. In those early days, these sites, located about 15 miles apart, afforded the DOE/NV the opportunity to use at least two technologies to manage its waste cost effectively. The Area 5 Radioactive Waste Management Site (RWMS) uses engineered shallow-land burial cells to dispose packaged waste while the Area 3 RWMS uses subsidence craters formed from underground testing of nuclear weapons for the disposal of packaged and unpackaged bulk waste. The paper describes the technical attributes of both Area 5 and Area 3 facilities, the acceptance process, the disposal processes, and present and future capacities of both sites.

  7. Preliminary Hazard Analysis for the Remote-Handled Low-Level Waste Disposal Facility

    Energy Technology Data Exchange (ETDEWEB)

    Lisa Harvego; Mike Lehto

    2010-02-01

    The need for remote handled low level waste (LLW) disposal capability has been identified. A new onsite, remote-handled LLW disposal facility has been identified as the highest ranked alternative for providing continued, uninterrupted remote-handled LLW disposal capability for remote-handled LLW that is generated as part of the nuclear mission of the Idaho National Laboratory and from spent nuclear fuel processing activities at the Naval Reactors Facility. Historically, this type of waste has been disposed of at the Radioactive Waste Management Complex. Disposal of remote-handled LLW in concrete disposal vaults at the Radioactive Waste Management Complex will continue until the facility is full or until it must be closed in preparation for final remediation of the Subsurface Disposal Area (approximately at the end of Fiscal Year 2017). This document supports the conceptual design for the proposed remote-handled LLW disposal facility by providing an initial nuclear facility hazard categorization and by identifying potential hazards for processes associated with onsite handling and disposal of remote-handled LLW.

  8. Preliminary Hazard Analysis for the Remote-Handled Low-Level Waste Disposal Project

    Energy Technology Data Exchange (ETDEWEB)

    Lisa Harvego; Mike Lehto

    2010-10-01

    The need for remote handled low level waste (LLW) disposal capability has been identified. A new onsite, remote-handled LLW disposal facility has been identified as the highest ranked alternative for providing continued, uninterrupted remote-handled LLW disposal capability for remote-handled LLW that is generated as part of the nuclear mission of the Idaho National Laboratory and from spent nuclear fuel processing activities at the Naval Reactors Facility. Historically, this type of waste has been disposed of at the Radioactive Waste Management Complex. Disposal of remote-handled LLW in concrete disposal vaults at the Radioactive Waste Management Complex will continue until the facility is full or until it must be closed in preparation for final remediation of the Subsurface Disposal Area (approximately at the end of Fiscal Year 2017). This document supports the conceptual design for the proposed remote-handled LLW disposal facility by providing an initial nuclear facility hazard categorization and by identifying potential hazards for processes associated with onsite handling and disposal of remote-handled LLW.

  9. Cemented materials in the LLW and MLW Spanish disposal

    Directory of Open Access Journals (Sweden)

    Guerrero, A.

    1999-09-01

    Full Text Available BWR and PWR cemented matrices to confine low and medium simulated liquid radioactive wastes have been submitted to the leaching process in de-ionized water at 20ºC and 40ºC, to obtain the medium leachability index (L and the effective diffusion coefficient (De of different ions. Otherwise, it has been studied the associated expansion of the backfilling mortar of the concrete containers of the Spanish repository of these wastes, due to a possible attack of the sulfate ions coming from the cemented matrices.

    Matrices cementicias confinantes tipo BWR y PWR de residuos simulados de baja y media radiactividad se han sometido a procesos de lixiviación en agua desionizada a 20ºC y 40ºC, obteniéndose los índices medios de lixiviación (L y el coeficiente de difusión efectiva (De de algunos iones. Por otra parte, se ha estudiado la expansión asociada a un mortero de relleno constitutivo del depósito de almacenamiento de los residuos, por posible ataque de los iones SO4-2 procedentes de las matrices.

  10. Phoenix Trenches

    Science.gov (United States)

    2008-01-01

    [figure removed for brevity, see original site] Annotated Version [figure removed for brevity, see original site] Left-eye view of a stereo pair [figure removed for brevity, see original site] Right-eye view of a stereo pair This image is a stereo, panoramic view of various trenches dug by NASA's Phoenix Mars Lander. The images that make up this panorama were taken by Phoenix's Surface Stereo Imager at about 4 p.m., local solar time at the landing site, on the 131st, Martian day, or sol, of the mission (Oct. 7, 2008). In figure 1, the trenches are labeled in orange and other features are labeled in blue. Figures 2 and 3 are the left- and right-eye members of a stereo pair. For scale, the 'Pet Donkey' trench just to the right of center is approximately 38 centimeters (15 inches) long and 31 to 34 centimeters (12 to 13 inches) wide. In addition, the rock in front of it, 'Headless,' is about 11.5 by 8.5 centimeters (4.5 by 3.3 inches), and about 5 centimeters (2 inches) tall. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  11. Project Execution Plan for the Remote Handled Low-Level Waste Disposal Project

    Energy Technology Data Exchange (ETDEWEB)

    Danny Anderson

    2014-07-01

    As part of ongoing cleanup activities at the Idaho National Laboratory (INL), closure of the Radioactive Waste Management Complex (RWMC) is proceeding under the Comprehensive Environmental Response, Compensation, and Liability Act (42 USC 9601 et seq. 1980). INL-generated radioactive waste has been disposed of at RWMC since 1952. The Subsurface Disposal Area (SDA) at RWMC accepted the bulk of INL’s contact and remote-handled low-level waste (LLW) for disposal. Disposal of contact-handled LLW and remote-handled LLW ion-exchange resins from the Advanced Test Reactor in the open pit of the SDA ceased September 30, 2008. Disposal of remote-handled LLW in concrete disposal vaults at RWMC will continue until the facility is full or until it must be closed in preparation for final remediation of the SDA (approximately at the end of fiscal year FY 2017). The continuing nuclear mission of INL, associated ongoing and planned operations, and Naval spent fuel activities at the Naval Reactors Facility (NRF) require continued capability to appropriately dispose of contact and remote handled LLW. A programmatic analysis of disposal alternatives for contact and remote-handled LLW generated at INL was conducted by the INL contractor in Fiscal Year 2006; subsequent evaluations were completed in Fiscal Year 2007. The result of these analyses was a recommendation to the Department of Energy (DOE) that all contact-handled LLW generated after September 30, 2008, be disposed offsite, and that DOE proceed with a capital project to establish replacement remote-handled LLW disposal capability. An analysis of the alternatives for providing replacement remote-handled LLW disposal capability has been performed to support Critical Decision-1. The highest ranked alternative to provide this required capability has been determined to be the development of a new onsite remote-handled LLW disposal facility to replace the existing remote-handled LLW disposal vaults at the SDA. Several offsite DOE

  12. Flow and transport at the Las Cruces trench site: Experiment IIb

    Energy Technology Data Exchange (ETDEWEB)

    Vinson, J.; Hills, R.G. [New Mexico State Univ., Las Cruces, NM (United States); Wierenga, P.J.; Young, M.H. [Arizona Univ., Tucson, AZ (United States). Dept. of Soil and Water Science

    1997-07-01

    The US Nuclear Regulatory Commission (NRC) has been directed by Congress in the Low Level Waste Policy Act of 1980 to develop regulatory guidance and assist the individual states and compacts in siting and assessing future low level radioactive waste (LLW) disposal facilities. Three water flow and solute transport experiments were performed as part of a comprehensive field trench study near Las Cruces, New Mexico to test deterministic and stochastic models of vadose zone flow and transport. This report presents partial results from the third experiment (experiment IIb). Experiments IIa and b were conducted on the North side of the trench, on a plot 1.22 m wide by 12 m long, perpendicular to the trench. The area was drip irrigated during two time periods with water containing a variety of tracers. The advance of the water front during the two irrigation episodes was measured with tensiometers and neutron probes. Solute front positions were determined from soil solution sampling through suction samplers and from disturbed sampling. The results from experiment IIb show predominantly downward water movement through the layered unsaturated soil, as evidenced from neutron probe data and gravimetric sampling. Tritium plumes were only half as deep and half as wide as the water plumes at 310 days after the beginning of experiment IIb. Chromium, applied as Cr(VI), moved a readily as, and similar to tritium, but there was a loss of mass due to reduction of Cr(VI) to Cr(III). Chloride and nitrate, initially present at high concentrations in the soil solution, were displaced by the low concentration irrigation water, resulting in chloride and nitrate concentration distributions that looked like negative images of the tritium distributions. The extensive data presented should serve well as a data base for model testing.

  13. LLW notes: Volume 10, Number 6

    Energy Technology Data Exchange (ETDEWEB)

    Norris, C. [ed.] [Afton Associates, Inc., Washington, DC (United States)

    1995-09-01

    The Low-Level Radioactive Waste Forum is an association of state and compact representatives, appointed by governors and compact commissions, established to facilitate state and compact implementation of the Low-Level Radioactive Waste Policy Act of 1980 and the Low-Level Radioactive Waste Policy Amendments Act of 1985 and to promote the objectives of low-level radioactive waste regional compacts. The LLW Forum provides an opportunity for state and compact officials to share information with one another and to exchange views with officials of federal agencies and other interested parties.

  14. LLW Notes: Volume 10, Number 7

    Energy Technology Data Exchange (ETDEWEB)

    Norris, C. [ed.] [Afton Associates, Inc., Washington, DC (United States)

    1995-10-01

    The Low-Level Radioactive Waste Forum is an association of state and compact representatives, appointed by governors and compact commissions, established to facilitate state and compact implementation of the Low-Level Radioactive Waste Policy Act of 1980 and the Low-Level Radioactive Waste Policy Amendments Act of 1985 and to promote the objectives of low-level radioactive waste regional compacts. The LLW Forum provides an opportunity for state and compact officials to share information with one another and to exchange views with officials of federal agencies and other interested parties.

  15. LLW Notes: Volume 10, Number 3

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-04-01

    The Low-Level Radioactive Waste Forum is an association of state and compact representatives, appointed by governors and compact commissions, established to facilitate state and compact implementation of the Low-Level Radioactive Waste Policy Act of 1980 and the Low-Level Radioactive Waste Policy Amendments Act of 1985 and to promote the objectives of low-level radioactive waste regional compacts. The LLW Forum provides an opportunity for state and compact officials to share information with one another and to exchange views with officials of federal agencies and other interested parties.

  16. Final disposal of radioactive waste

    OpenAIRE

    Freiesleben H.

    2013-01-01

    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 c...

  17. Conceptual Safety Design Report for the Remote Handled Low-Level Waste Disposal Facility

    Energy Technology Data Exchange (ETDEWEB)

    Boyd D. Christensen

    2010-02-01

    A new onsite, remote-handled LLW disposal facility has been identified as the highest ranked alternative for providing continued, uninterrupted remote-handled LLW disposal for remote-handled LLW from the Idaho National Laboratory and for spent nuclear fuel processing activities at the Naval Reactors Facility. Historically, this type of waste has been disposed of at the Radioactive Waste Management Complex. Disposal of remote-handled LLW in concrete disposal vaults at the Radioactive Waste Management Complex will continue until the facility is full or until it must be closed in preparation for final remediation of the Subsurface Disposal Area (approximately at the end of Fiscal Year 2017). This conceptual safety design report supports the design of a proposed onsite remote-handled LLW disposal facility by providing an initial nuclear facility hazard categorization, by identifying potential hazards for processes associated with onsite handling and disposal of remote-handled LLW, by evaluating consequences of postulated accidents, and by discussing the need for safety features that will become part of the facility design.

  18. Addendum to the Closure Report for Corrective Action Unit 404: Roller Coaster Sewage Lagoons and North Disposal Trench, Tonopah Test Range, Nevada, Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    Lynn Kidman

    2009-02-01

    This document constitutes an addendum to the September 1998, Closure Report for Corrective Action Unit 404: Roller Coaster Lagoons and Trench, Tonopah Test Range, Nevada as described in the document Recommendations and Justifications for Modifications for Use Restrictions Established under the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office Federal Facility Agreement and Consent Order (UR Modification document) dated February 2008. The UR Modification document was approved by NDEP on February 26, 2008. The approval of the UR Modification document constituted approval of each of the recommended UR modifications. In conformance with the UR Modification document, this addendum consists of: • This cover page that refers the reader to the UR Modification document for additional information • The cover and signature pages of the UR Modification document • The NDEP approval letter • The corresponding section of the UR Modification document This addendum provides the documentation justifying the modification of the UR for CAS TA-03-001-TARC Roller Coaster Lagoons. This UR was established as part of Federal Facility Agreement and Consent Order (FFACO) corrective actions and was based on the presence of contaminants at concentrations greater than the action levels established at the time of the initial investigation (FFACO, 1996; as amended August 2006). Since this UR was established, practices and procedures relating to the implementation of risk-based corrective actions (RBCA) have changed. Therefore, this UR was re-evaluated against the current RBCA criteria as defined in the Industrial Sites Project Establishment of Final Action Levels (NNSA/NSO, 2006c). This reevaluation consisted of comparing the original data (used to define the need for the UR) to risk-based final action levels (FALs) developed using the current Industrial Sites RBCA process. The re-evaluation resulted in a recommendation to modify the UR for CAS TA-03

  19. Closure Strategy for a Waste Disposal Facility with Multiple Waste Types and Regulatory Drivers at the Nevada Test Site

    Energy Technology Data Exchange (ETDEWEB)

    D. Wieland, V. Yucel, L. Desotell, G. Shott, J. Wrapp

    2008-04-01

    The U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office (NNSA/NSO) plans to close the waste and classified material storage cells in the southeast quadrant of the Area 5 Radioactive Waste Management Site (RWMS), informally known as the '92-Acre Area', by 2011. The 25 shallow trenches and pits and the 13 Greater Confinement Disposal (GCD) borings contain various waste streams including low-level waste (LLW), low-level mixed waste (LLMW), transuranic (TRU), mixed transuranic (MTRU), and high specific activity LLW. The cells are managed under several regulatory and permit programs by the U.S. Department of Energy (DOE) and the Nevada Division of Environmental Protection (NDEP). Although the specific closure requirements for each cell vary, 37 closely spaced cells will be closed under a single integrated monolayer evapotranspirative (ET) final cover. One cell will be closed under a separate cover concurrently. The site setting and climate constrain transport pathways and are factors in the technical approach to closure and performance assessment. Successful implementation of the integrated closure plan requires excellent communication and coordination between NNSA/NSO and the regulators.

  20. Assessment of Preferred Depleted Uranium Disposal Forms

    Energy Technology Data Exchange (ETDEWEB)

    Croff, A.G.; Hightower, J.R.; Lee, D.W.; Michaels, G.E.; Ranek, N.L.; Trabalka, J.R.

    2000-06-01

    The Department of Energy (DOE) is in the process of converting about 700,000 metric tons (MT) of depleted uranium hexafluoride (DUF6) containing 475,000 MT of depleted uranium (DU) to a stable form more suitable for long-term storage or disposal. Potential conversion forms include the tetrafluoride (DUF4), oxide (DUO2 or DU3O8), or metal. If worthwhile beneficial uses cannot be found for the DU product form, it will be sent to an appropriate site for disposal. The DU products are considered to be low-level waste (LLW) under both DOE orders and Nuclear Regulatory Commission (NRC) regulations. The objective of this study was to assess the acceptability of the potential DU conversion products at potential LLW disposal sites to provide a basis for DOE decisions on the preferred DU product form and a path forward that will ensure reliable and efficient disposal.

  1. Geochemical effects on the behavior of LLW radionuclides in soil/groundwater environments

    Energy Technology Data Exchange (ETDEWEB)

    Krupka, K.M.; Sterne, R.J. [Pacific Northwest Lab., Richland, WA (United States)

    1995-12-31

    Assessing the migration potential of radionuclides leached from low-level radioactive waste (LLW) and decommissioning sites necessitates information on the effects of sorption and precipitation on the concentrations of dissolved radionuclides. Such an assessment requires that the geochemical processes of aqueous speciation, complexation, oxidation/reduction, and ion exchange be taken into account. The Pacific Northwest National Laboratory (PNNL) is providing technical support to the U.S. Nuclear Regulatory Commission (NRC) for defining the solubility and sorption behavior of radionuclides in soil/ground-water environments associated with engineered cementitious LLW disposal systems and decommissioning sites. Geochemical modeling is being used to predict solubility limits for radionuclides under geochemical conditions associated with these environments. The solubility limits are being used as maximum concentration limits in performance assessment calculations describing the release of contaminants from waste sources. Available data were compiled regarding the sorption potential of radionuclides onto {open_quotes}fresh{close_quotes} cement/concrete where the expected pH of the cement pore waters will equal to or exceed 10. Based on information gleaned from the literature, a list of preferred minimum distribution coefficients (Kd`s) was developed for these radionuclides. The K{sub d} values are specific to the chemical environments associated with the evolution of the compositions of cement/concrete pore waters.

  2. Review of private sector and Department of Energy treatment, storage, and disposal capabilities for low-level and mixed low-level waste

    Energy Technology Data Exchange (ETDEWEB)

    Willson, R.A.; Ball, L.W.; Mousseau, J.D.; Piper, R.B.

    1996-03-01

    Private sector capacity for treatment, storage, and disposal (TSD) of various categories of radioactive waste has been researched and reviewed for the Idaho National Engineering Laboratory (INEL) by Lockheed Idaho Technologies Company, the primary contractor for the INEL. The purpose of this document is to provide assistance to the INEL and other US Department of Energy (DOE) sites in determining if private sector capabilities exist for those waste streams that currently cannot be handled either on site or within the DOE complex. The survey of private sector vendors was limited to vendors currently capable of, or expected within the next five years to be able to perform one or more of the following services: low-level waste (LLW) volume reduction, storage, or disposal; mixed LLW treatment, storage, or disposal; alpha-contaminated mixed LLW treatment; LLW decontamination for recycling, reclamation, or reuse; laundering of radioactively-contaminated laundry and/or respirators; mixed LLW treatability studies; mixed LLW treatment technology development. Section 2.0 of this report will identify the approach used to modify vendor information from previous revisions of this report. It will also illustrate the methodology used to identify any additional companies. Section 3.0 will identify, by service, specific vendor capabilities and capacities. Because this document will be used to identify private sector vendors that may be able to handle DOE LLW and mixed LLW streams, it was decided that current DOE capabilities should also be identified. This would encourage cooperation between DOE sites and the various states and, in some instances, may result in a more cost-effective alternative to privatization. The DOE complex has approximately 35 sites that generate the majority of both LLW and mixed LLW. Section 4.0 will identify these sites by Operations Office, and their associated LLW and mixed LLW TSD units.

  3. EPRI`s LLW Research and Development Program

    Energy Technology Data Exchange (ETDEWEB)

    Hornibrook, C. [EPRI, Palo Alto, CA (United States)

    1996-10-01

    In this report the author summarizes EPRI work related to the minimization of low-level radioactive wastes (LLW) from nuclear power plants. The emphasis of these programs is to handle LLW with less cost, more efficiency with lower exposure, and more easily. The R&D programs which EPRI is conducting are summarized, as well as the approach EPRI is using in attacking the problem in general, involving not only basic research, but help in implementing programs, on-site verifications, demonstration programs, and the development of test facilities. Selected reports available from EPRI providing guidance on these issues are reviewed, along with delivery dates for reports on research in progress.

  4. LLW Forum meeting report, October 26--27, 1994

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-12-31

    The Low-Level Radioactive Waste Forum (LLW Forum) is an association of state and compact representatives, appointed by governors and compact commissions, established to facilitate state and compact implementation of the Low-Level Radioactive Waste Policy Act of 1980 and the Low-Level Radioactive Waste Policy Amendments Act of 1985 and to promote the objectives of low-level radioactive waste regional compacts. The LLW Forum provides an opportunity for state and compact officials to share information with one another and to exchange views with officials of federal agencies and other interested parties. This report details activities of the meeting held October 26-27, 1994.

  5. Final disposal of radioactive waste

    Science.gov (United States)

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, T.L.; Lewis, B.E.; Turner, K.H.; Rozelle, M.A. [Dames and Moore, Denver, CO (United States)

    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.

  7. National Environmental Policy Act Compliance Strategy for the Remote-Handled Low-level Waste Disposal Facility

    Energy Technology Data Exchange (ETDEWEB)

    Peggy Hinman

    2010-10-01

    The U.S. Department of Energy (DOE) needs to have disposal capability for remote-handled low level waste (LLW) generated at the Idaho National Laboratory (INL) at the time the existing disposal facility is full or must be closed in preparation for final remediation of the INL Subsurface Disposal Area in approximately the year 2017.

  8. LLW Notes, Volume 12, Number 7

    Energy Technology Data Exchange (ETDEWEB)

    Norris, C.; Brown, H. [eds.; Gedden, R.; Lovinger, T.; Scheele, L.; Shaker, M.A.

    1997-09-01

    Contents include articles entitled: House votes 309 to 107 to approve Texas compact; Nebraska governor hosts LLRW meeting; Southeast Compact considers funding proposal; Chem-Nuclear explores options re SC revenue requirements; Legislation sets revenue requirements for Barnwell; TCC meets: Supports CA request for technical assistance; DOE approves part of California`s technical assistance request; State legislators discuss LLRW management for OH, IL, NC; Washington governor re Potential New Hanford Role; Federal court enjoins DOE from excluding WCS on new disposal; Appellate court in favor of DOE in surcharge rebates dispute; Hearing set for October in Ward Valley case; court rejects federal motion to dismiss Ward Valley suit; NE sues commission re veto over export authorizations; US Supreme Court dismisses line-item veto challenge; Department of Interior Inspector General investigation requested; USEC privatization plan approved; DOD finalizes LLRW disposal charter; Clinton nominates six DOE appointees; Congress moves FUSRAP to Army Corps of Engineers; Schaefer named interim director of USGS: Nichols leaves EPA: NRC Commissioner Rogers` term expires; NRC: CA ``Well-Quantified`` to license Ward Valley facility; EPA objects to state permit for Louisiana facility; Petitions submitted to EPA oppose Shintech permits; ECOS draft recommendations re Enviro programs; Legislation introduced to prohibit spent fuel shipments to the Goshutes; and HLW legislation ready for floor action.

  9. LLW Notes, vol.9, no. 5. August/September 1994

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-09-01

    LLW Notes is distributed to Low-Level Radioactive Waste Forum Participants and other state and compact officials identified by those Participants to receive LLW Notes. The Low-Level Radioactive Waste Forum is an association of state and compact representatives appointed by governors and compact commissions, established to facilitate state and compact commission implementation of the Low- Level Radioactive Waste Policy Act of 1980 and the Low-Level Radioactive Waste Policy Amendments Act of 1985 and to promote the objectives of low-level radioactive waste regional compacts. The Forum provides an opportunity for states and compacts to share information with one another and to exchange views with officials of federal agencies and other interested parties.

  10. LLW Notes, volume 9, No. 7. November and December 1994

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-12-01

    LLW Notes is distributed to Low-Level Radioactive Waste Forum Participants and other state and compact officials identified by those Participants to receive LLW Notes. The Low-Level Radioactive Waste Forum is an association of state and compact representatives appointed by governors and compact commissions, established to facilitate state and compact commission implementation of the Low- Level Radioactive Waste Policy Act of 1980 and the Low-Level Radioactive Waste Policy Amendments Act of 1985 and to promote the objectives of low-level radioactive waste regional compacts. The Forum provides an opportunity for states and compacts to share information with one another and to exchange views with officials of federal agencies and other interested parties.

  11. WRAP low level waste (LLW) glovebox acceptance test report

    Energy Technology Data Exchange (ETDEWEB)

    Leist, K.J.

    1998-02-17

    In June 28, 1997, the Low Level Waste (LLW) glovebox was tested using glovebox acceptance test procedure 13031A-85. The primary focus of the glovebox acceptance test was to examine control system interlocks, display menus, alarms, and operator messages. Limited mechanical testing involving the drum ports, hoists, drum lifter, compacted drum lifter, drum tipper, transfer car, conveyors, lidder/delidder device and the supercompactor were also conducted. As of November 24, 1997, 2 of the 131 test exceptions that affect the LLW glovebox remain open. These items will be tracked and closed via the WRAP Master Test Exception Database. As part of Test Exception resolution/closure the responsible individual closing the Test Exception performs a retest of the affected item(s) to ensure the identified deficiency is corrected, and, or to test items not previously available to support testing. Test Exceptions are provided as appendices to this report.

  12. LLW Notes, Volume 9, Number 6. October 1994

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-10-01

    LLW Notes is distributed to Low-Level Radioactive Waste Forum Participants and other state and compact officials identified by those Participants to receive LLW Notes. The Low-Level Radioactive Waste Forum is an association of state and compact representatives appointed by governors and compact commissions, established to facilitate state and compact commission implementation of the Low- Level Radioactive Waste Policy Act of 1980 and the Low-Level Radioactive Waste Policy Amendments Act of 1985 and to promote the objectives of low-level radioactive waste regional compacts. The Forum provides an opportunity for states and compacts to share information with one another and to exchange views with officials of federal agencies and other interested parties.

  13. LLW Notes supplement, Volume 12, Number 2

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-02-01

    Federal criteria for determining whether a project presents an environmental justice concern are currently subject to multiple interpretations. There are no federal statutes or regulations that specifically reference or address environmental justice, and the guidelines that are being developed by the Council on Environmental Quality are currently in draft form. The lack of consistent and clear federal criteria for determining what constitutes an environmental justice impact--and how to determine whether environmental justice issues have been effectively addressed--can create a dilemma for state agencies that wish to include--or have already included--environmental justice, along with legal, economic and technical issues, as a consideration when siting a facility. The following information is therefore provided for those agencies and commissions seeking to site, to license, to construct and to operate a low-level radioactive waste disposal facility. Topics include: National Environmental Justice Advisory Council; NEJAC members; Federal definitions of environmental justice; and EPA`s role in federal land transfers. Federal agencies can achieve environmental justice by identifying and addressing--as appropriate--disproportionately high and adverse human health or environmental effects of [federal agency] programs, policies, and activities on minority populations and low-income populations.

  14. Strategy for identifying natural analogs of the long-term performance of low-level waste disposal sites

    Energy Technology Data Exchange (ETDEWEB)

    Chatters, J.C.; Waugh, W.J.; Foley, M.G.; Kincaid, C.T.

    1990-07-01

    The US Department of Energy's Low-Level Waste (LLW) Management Program has asked Pacific Northwest Laboratory (PNL) to explore the feasibility of using natural analogs of anticipated waste site and conditions to help validate predictions of the performance of LLW disposal sites. Current regulations require LLW facilities to control the spread of hazardous substances into the environment for at least the next 500 years. Natural analog studies can provide information about processes affecting waste containment that cannot be fully explored through laboratory experimentation and modeling because of the extended period of required performance. For LLW applications, natural analogs include geochemical systems, pedogenic (soil formation) indicators, proxy climate data, and ecological and archaeological settings that portray long-term changes in disposal site environments and the survivability of proposed waste containment materials and structures. Analog data consist of estimates of performance assessment (PA) model input parameters that define possible future environmental states of waste sites, validation parameters that can be predicted by PA models, and descriptive information that can build public confidence in waste disposal practices. This document describes PNL's overall stategy for identifying analogs for LLW disposal systems, reviews lessons learned from past analogs work, outlines the findings of the workshop, and presents examples of analog studies that workshop participants found to be applicable to LLW performance assessment. The lessons from the high-level waste analogs experience and workshop discussions will be used to develop detailed study plans during FY 1990. 39 refs.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  16. Siting Study for the Remote-Handled Low-Level Waste Disposal Project

    Energy Technology Data Exchange (ETDEWEB)

    Lisa Harvego; Joan Connolly; Lance Peterson; Brennon Orr; Bob Starr

    2010-10-01

    The U.S. Department of Energy has identified a mission need for continued disposal capacity for remote-handled low-level waste (LLW) generated at the Idaho National Laboratory (INL). An alternatives analysis that was conducted to evaluate strategies to achieve this mission need identified two broad options for disposal of INL generated remote-handled LLW: (1) offsite disposal and (2) onsite disposal. The purpose of this study is to identify candidate sites or locations within INL boundaries for the alternative of an onsite remote handled LLW disposal facility and recommend the highest-ranked locations for consideration in the National Environmental Policy Act process. The study implements an evaluation based on consideration of five key elements: (1) regulations, (2) key assumptions, (3) conceptual design, (4) facility performance, and (5) previous INL siting study criteria, and uses a five-step process to identify, screen, evaluate, score, and rank 34 separate sites located across INL. The result of the evaluation is identification of two recommended alternative locations for siting an onsite remote-handled LLW disposal facility. The two alternative locations that best meet the evaluation criteria are (1) near the Advanced Test Reactor Complex and (2) west of the Idaho Comprehensive Environmental Response, Compensation, and Liability Act Disposal Facility.

  17. Trench 'bathtubbing' and surface plutonium contamination at a legacy radioactive waste site.

    Science.gov (United States)

    Payne, Timothy E; Harrison, Jennifer J; Hughes, Catherine E; Johansen, Mathew P; Thiruvoth, Sangeeth; Wilsher, Kerry L; Cendón, Dioni I; Hankin, Stuart I; Rowling, Brett; Zawadzki, Atun

    2013-01-01

    Radioactive waste containing a few grams of plutonium (Pu) was disposed between 1960 and 1968 in trenches at the Little Forest Burial Ground (LFBG), near Sydney, Australia. A water sampling point installed in a former trench has enabled the radionuclide content of trench water and the response of the water level to rainfall to be studied. The trench water contains readily measurable Pu activity (~12 Bq/L of (239+240)Pu in 0.45 μm-filtered water), and there is an associated contamination of Pu in surface soils. The highest (239+240)Pu soil activity was 829 Bq/kg in a shallow sample (0-1 cm depth) near the trench sampling point. Away from the trenches, the elevated concentrations of Pu in surface soils extend for tens of meters down-slope. The broader contamination may be partly attributable to dispersion events in the first decade after disposal, after which a layer of soil was added above the trenched area. Since this time, further Pu contamination has occurred near the trench-sampler within this added layer. The water level in the trench-sampler responds quickly to rainfall and intermittently reaches the surface, hence the Pu dispersion is attributed to saturation and overflow of the trenches during extreme rainfall events, referred to as the 'bathtub' effect.

  18. Trench ‘Bathtubbing’ and Surface Plutonium Contamination at a Legacy Radioactive Waste Site

    Science.gov (United States)

    2013-01-01

    Radioactive waste containing a few grams of plutonium (Pu) was disposed between 1960 and 1968 in trenches at the Little Forest Burial Ground (LFBG), near Sydney, Australia. A water sampling point installed in a former trench has enabled the radionuclide content of trench water and the response of the water level to rainfall to be studied. The trench water contains readily measurable Pu activity (∼12 Bq/L of 239+240Pu in 0.45 μm-filtered water), and there is an associated contamination of Pu in surface soils. The highest 239+240Pu soil activity was 829 Bq/kg in a shallow sample (0–1 cm depth) near the trench sampling point. Away from the trenches, the elevated concentrations of Pu in surface soils extend for tens of meters down-slope. The broader contamination may be partly attributable to dispersion events in the first decade after disposal, after which a layer of soil was added above the trenched area. Since this time, further Pu contamination has occurred near the trench-sampler within this added layer. The water level in the trench-sampler responds quickly to rainfall and intermittently reaches the surface, hence the Pu dispersion is attributed to saturation and overflow of the trenches during extreme rainfall events, referred to as the ‘bathtub’ effect. PMID:24256473

  19. Snow White Trenches

    Science.gov (United States)

    2008-01-01

    This image was acquired by NASA's Phoenix Mars Lander's Surface Stereo Imager on the 25th Martian day of the mission, or Sol 24 (June 19, 2008), after the May 25, 2008, landing. This image shows the trenches informally called 'Snow White 1' (left) and 'Snow White 2' (right). The trench is about 5 centimeters (2 inches) deep and 30 centimeters (12 inches) long. 'Snow White' is located in a patch of Martian soil near the center of a polygonal surface feature, nicknamed 'Cheshire Cat.' The 'dump pile' is located at the top of the trench, the side farthest away from the lander, and has been dubbed 'Croquet Ground.' The digging site has been named 'Wonderland.' This image has been enhanced to brighten shaded areas. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  20. 'Snow White' Trench

    Science.gov (United States)

    2008-01-01

    This image was acquired by NASA's Phoenix Mars Lander's Surface Stereo Imager on Sol 43, the 43rd Martian day after landing (July 8, 2008). This image shows the trench informally called 'Snow White.' Two samples were delivered to the Wet Chemistry Laboratory, which is part of Phoenix's Microscopy, Electrochemistry, and Conductivity Analyzer (MECA). The first sample was taken from the surface area just left of the trench and informally named 'Rosy Red.' It was delivered to the Wet Chemistry Laboratory on Sol 30 (June 25, 2008). The second sample, informally named 'Sorceress,' was taken from the center of the 'Snow White' trench and delivered to the Wet Chemistry Laboratory on Sol 41 (July 6, 2008). The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  1. Offset trench isolation

    Science.gov (United States)

    Roth, S. S.; Cooper, K. J.; Ray, W.; Kirsch, H. C.; Grove, Charlotte

    1994-08-01

    Feasibility of a new, recessed isolation technique that utilizes an offset, shallow trench in combination with thermal oxidation for achieving near zero final encroachment with excellent planarity is demonstrated. Etch of the shallow trench is offset from the original hardmask by an oxide sidewall spacer. After trench etch, HF is used to remove the hardmask oxide and sidewall spacers and to form a cavity which is self-aligned to the nitride edge. Exposed silicon regions are then reoxidized and encapsulated with polysilicon. Field oxide is then grown. The final field oxide profile exhibits steep sidewall angles without inducing substrate defects as evidenced by low diode leakage. Other isolation sensitive device parametrics such as gate oxide quality and metal oxide semiconductor field effect transistor threshold voltage stability are presented and exhibit good characteristics.

  2. Standardization of DOE Disposal Facilities Waste Acceptance Processes

    Energy Technology Data Exchange (ETDEWEB)

    Shrader, T. A.; Macbeth, P. J.

    2002-02-26

    On February 25, 2000, the U.S. Department of Energy (DOE) issued the Record of Decision (ROD) for the Waste Management Programmatic Environmental Impact Statement (WM PEIS) for low-level and mixed low-level wastes (LLW/ MLLW) treatment and disposal. The ROD designated the disposal sites at Hanford and the Nevada Test Site (NTS) to dispose of LLW/MLLW from sites without their own disposal facilities. DOE's Richland Operations Office (RL) and the National Nuclear Security Administration's Nevada Operations Office (NV) have been charged with effectively implementing the ROD. To accomplish this task NV and RL, assisted by their operating contractors Bechtel Nevada (BN), Fluor Hanford (FH), and Bechtel Hanford (BH) assembled a task team to systematically map out and evaluate the current waste acceptance processes and develop an integrated, standardized process for the acceptance of LLW/MLLW. A structured, systematic, analytical process using the Six Sigma system identified dispos al process improvements and quantified the associated efficiency gains to guide changes to be implemented. The review concluded that a unified and integrated Hanford/NTS Waste Acceptance Process would be a benefit to the DOE Complex, particularly the waste generators. The Six Sigma review developed quantitative metrics to address waste acceptance process efficiency improvements, and provides an initial look at development of comparable waste disposal cost models between the two disposal sites to allow quantification of the proposed improvements.

  3. Phoenix's Snow White Trench

    Science.gov (United States)

    2008-01-01

    A soil sample taken from the informally named 'Snow White' trench at NASA's Phoenix Mars Lander work site produced minerals that indicate evidence of past interaction between the minerals and liquid water. This image was taken by the Surface Stereo Imager on Sol 103, the 103rd day since landing (Sept. 8, 2008). The trench is approximately 23 centimeters (9 inches) long. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by JPL, Pasadena, Calif. Spacecraft development was by Lockheed Martin Space Systems, Denver.

  4. LLW Forum meeting report, July 20--22, 1994

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-12-31

    The Low-Level Radioactive Waste Forum (LLW Forum) is an association of state and compact representative, appointed by governors and compact commissions, established to facilitate state and compact commission implementation of the Low-Level radioactive Waste Policy Act of 1980 and the Low-Level Radioactive Waste Policy Amendments act of 1985 and to promote the objectives of low-level radioactive waste regional compacts. The forum provides an opportunity for states and compacts to share information with one another and to exchange views with officials of federal agencies. This report details activities of the meeting held July 20-22, 1994.

  5. Low-level waste inventory, characteristics, generation, and facility assessment for treatment, storage, and disposal alternatives considered in the US Department of Energy waste management programmatic environmental impact statement

    Energy Technology Data Exchange (ETDEWEB)

    Goyette, M.L.; Dolak, D.A.

    1996-12-01

    This report provides technical support information for use in analyzing environmental impacts associated with U.S. Department of Energy (DOE) low-level radioactive waste (LLW) management alternatives in the Waste-Management (WM) Programmatic Environmental Impact Statement (PEIS). Waste loads treated and disposed of for each of the LLW alternatives considered in the DOE WM PEIS are presented. Waste loads are presented for DOE Waste Management (WM) wastes, which are generated from routine operations. Radioactivity concentrations and waste quantities for treatment and disposal under the different LLW alternatives are described for WM waste. 76 refs., 14 figs., 42 tabs.

  6. Snow White 5 Trench

    Science.gov (United States)

    2008-01-01

    This image was acquired by NASA's Phoenix Mars Lander's Robotic Arm Camera on the 35th Martian day of the mission, or Sol 34 (June 29, 2008), after the May 25, 2008, landing. This image shows the trench informally called 'Snow White 5.' The trench is 4-to-5 centimeters (about 1.5-to-1.9 inches) deep, 24 centimeters (about 9 inches) wide and 33 centimeters (13 inches) long. Snow White 5 is Phoenix's current active digging area after additional trenching, grooming, and scraping by Phoenix's Robotic Arm in the last few sols to trenches informally called Snow White 1, 2, 3, and 4. Near the top center of the image is the Robotic Arm's Thermal and Electrical Conductivity Probe. Snow White 5 is located in a patch of Martian soil near the center of a polygonal surface feature, nicknamed 'Cheshire Cat.' The digging site has been named 'Wonderland.' This image has been enhanced to brighten shaded areas. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  7. WRAP low level waste (LLW) glovebox operational test report

    Energy Technology Data Exchange (ETDEWEB)

    Kersten, J.K.

    1998-02-19

    The Low Level Waste (LLW) Process Gloveboxes are designed to: receive a 55 gallon drum in an 85 gallon overpack in the Entry glovebox (GBIOI); and open and sort the waste from the 55 gallon drum, place the waste back into drum and relid in the Sorting glovebox (GB 102). In addition, waste which requires further examination is transferred to the LLW RWM Glovebox via the Drath and Schraeder Bagiess Transfer Port (DO-07-201) or sent to the Sample Transfer Port (STC); crush the drum in the Supercompactor glovebox (GB 104); place the resulting puck (along with other pucks) into another 85 gallon overpack in the Exit glovebox (GB 105). The status of the waste items is tracked by the Data Management System (DMS) via the Plant Control System (PCS) barcode interface. As an item is moved from the entry glovebox to the exit glovebox, the Operator will track an items location using a barcode reader and enter any required data on the DMS console. The Operational Test Procedure (OTP) will perform evolution`s (described below) using the Plant Operating Procedures (POP) in order to verify that they are sufficient and accurate for controlled glovebox operation.

  8. Concepts and Technologies for Radioactive Waste Disposal in Rock Salt

    Directory of Open Access Journals (Sweden)

    Wernt Brewitz

    2007-01-01

    Full Text Available In Germany, rock salt was selected to host a repository for radioactive waste because of its excellent mechanical properties. During 12 years of practical disposal operation in the Asse mine and 25 years of disposal in the disused former salt mine Morsleben, it was demonstrated that low-level wastes (LLW and intermediate-level wastes (ILW can be safely handled and economically disposed of in salt repositories without a great technical effort. LLW drums were stacked in old mining chambers by loading vehicles or emplaced by means of the dumping technique. Generally, the remaining voids were backfilled by crushed salt or brown coal filter ash. ILW were lowered into inaccessible chambers through a borehole from a loading station above using a remote control.Additionally, an in-situ solidification of liquid LLW was applied in the Morsleben mine. Concepts and techniques for the disposal of heat generating high-level waste (HLW are advanced as well. The feasibility of both borehole and drift disposal concepts have been proved by about 30 years of testing in the Asse mine. Since 1980s, several full-scale in-situ tests were conducted for simulating the borehole emplacement of vitrified HLW canisters and the drift emplacement of spent fuel in Pollux casks. Since 1979, the Gorleben salt dome has been investigated to prove its suitability to host the national final repository for all types of radioactive waste. The “Concept Repository Gorleben” disposal concepts and techniques for LLW and ILW are widely based on the successful test operations performed at Asse. Full-scale experiments including the development and testing of adequate transport and emplacement systems for HLW, however, are still pending. General discussions on the retrievability and the reversibility are going on.

  9. High Density Faraday Cup Array or Other Open Trench Structures and Method of Manufacture Thereof

    Science.gov (United States)

    Bower, Christopher A. (Inventor); Gilchrist, Kristin Hedgepath (Inventor); Stoner, Brian R. (Inventor)

    2014-01-01

    A detector array and method for making the detector array. The detector array includes a substrate including a plurality of trenches formed therein, and a plurality of collectors electrically isolated from each other, formed on the walls of the trenches, and configured to collect charged particles incident on respective ones of the collectors and to output from the collectors signals indicative of charged particle collection. In the detector array, adjacent ones of the plurality of trenches are disposed in a staggered configuration relative to one another. The method forms in a substrate a plurality of trenches across a surface of the substrate such that adjacent ones of the trenches are in a staggered sequence relative to one another, forms in the plurality of trenches a plurality of collectors, and connects a plurality of electrodes respectively to the collectors.

  10. Mixed waste characterization, treatment & disposal focus area

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-08-01

    The mission of the Mixed Waste Characterization, Treatment, and Disposal Focus Area (referred to as the Mixed Waste Focus Area or MWFA) is to provide treatment systems capable of treating DOE`s mixed waste in partnership with users, and with continual participation of stakeholders, tribal governments, and regulators. The MWFA deals with the problem of eliminating mixed waste from current and future storage in the DOE complex. Mixed waste is waste that contains both hazardous chemical components, subject to the requirements of the Resource Conservation and Recovery Act (RCRA), and radioactive components, subject to the requirements of the Atomic Energy Act. The radioactive components include transuranic (TRU) and low-level waste (LLW). TRU waste primarily comes from the reprocessing of spent fuel and the use of plutonium in the fabrication of nuclear weapons. LLW includes radioactive waste other than uranium mill tailings, TRU, and high-level waste, including spent fuel.

  11. Phoenix's La Mancha Trench

    Science.gov (United States)

    2008-01-01

    This false color image, taken by NASA's Phoenix Mars Lander's Surface Stereo Imager, was taken on the 131st Martian day, or sol, of the mission (Oct. 7, 2008). The image shows color variations of the trench, informally named 'La Mancha,' and reveals the ice layer beneath the soil surface. The trench's depth is about 5 centimeters deep. The color outline of the shadow at the bottom of the image is a result of sun movement with the combined use of infrared, green, and blue filters. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  12. Snow White Trench (Animation)

    Science.gov (United States)

    2008-01-01

    [figure removed for brevity, see original site] Click on image for animation This animation shows the evolution of the trench called 'Snow White' that NASA's Phoenix Mars Lander began digging on the 22nd Martian day of the mission after the May 25, 2008, landing. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  13. Final disposal of radioactive waste

    Directory of Open Access Journals (Sweden)

    Freiesleben H.

    2013-06-01

    Full Text Available 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.

  14. Cleanup Verification Package for the 116-K-2 Effluent Trench

    Energy Technology Data Exchange (ETDEWEB)

    J. M. Capron

    2006-04-04

    This cleanup verification package documents completion of remedial action for the 116-K-2 effluent trench, also referred to as the 116-K-2 mile-long trench and the 116-K-2 site. During its period of operation, the 116-K-2 site was used to dispose of cooling water effluent from the 105-KE and 105-KW Reactors by percolation into the soil. This site also received mixed liquid wastes from the 105-KW and 105-KE fuel storage basins, reactor floor drains, and miscellaneous decontamination activities.

  15. Stormwater infiltration trenches: a conceptual modelling approach.

    Science.gov (United States)

    Freni, Gabriele; Mannina, Giorgio; Viviani, Gaspare

    2009-01-01

    In recent years, limitations linked to traditional urban drainage schemes have been pointed out and new approaches are developing introducing more natural methods for retaining and/or disposing of stormwater. These mitigation measures are generally called Best Management Practices or Sustainable Urban Drainage System and they include practices such as infiltration and storage tanks in order to reduce the peak flow and retain part of the polluting components. The introduction of such practices in urban drainage systems entails an upgrade of existing modelling frameworks in order to evaluate their efficiency in mitigating the impact of urban drainage systems on receiving water bodies. While storage tank modelling approaches are quite well documented in literature, some gaps are still present about infiltration facilities mainly dependent on the complexity of the involved physical processes. In this study, a simplified conceptual modelling approach for the simulation of the infiltration trenches is presented. The model enables to assess the performance of infiltration trenches. The main goal is to develop a model that can be employed for the assessment of the mitigation efficiency of infiltration trenches in an integrated urban drainage context. Particular care was given to the simulation of infiltration structures considering the performance reduction due to clogging phenomena. The proposed model has been compared with other simplified modelling approaches and with a physically based model adopted as benchmark. The model performed better compared to other approaches considering both unclogged facilities and the effect of clogging. On the basis of a long-term simulation of six years of rain data, the performance and the effectiveness of an infiltration trench measure are assessed. The study confirmed the important role played by the clogging phenomenon on such infiltration structures.

  16. LLW Forum meeting report, April 18--19, 1991

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1991-12-31

    The Low-Level Radioactive Waste Forum is an association of representatives of states and compacts established to facilitate state and compact commission implementation of the Low-Level Radioactive Waste Policy Act of 1980 and the Low-Level Radioactive Waste Policy Amendments Act of 1985 and to promote the objectives of low-level radioactive waste regional compacts. The Forum provides an opportunity for states and compacts to share information with one another and to exchange views with officials of federal agencies. LLW Forum participants include representatives from regional compacts, designated host states, unaffiliated states, and states with currently- operating low-level radioactive waste facilities. This quarterly meeting was held on April 18-19, 1991.

  17. LLW Forum meeting report, April 25--27, 1994

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-12-31

    The Low-Level radioactive Waste Forum is an association of representatives of states and compacts established to facilitate state and compact commission implementation of the Low-Level Radioactive Waste Policy Act of 1980 and the Low-Level Radioactive Waste Policy Amendments Act of 1985 and to promote the objectives of low-level radioactive waste regional compacts. The Forum provides an opportunity for states and compacts to share information with one another and to exchange views with officials of federal agencies. LLW Forum participants include representatives from regional compacts, designated host states, unaffiliated states, and states with currently-operating low-level radioactive waste facilities. This quarterly meeting was held April 25-27, 1994 and activities during the first quarter of 1994 are detailed..

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

    Energy Technology Data Exchange (ETDEWEB)

    Zarling, John [Los Alamos National Laboratory; Johnson, Peter [Los Alamos National Laboratory

    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?

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

    Science.gov (United States)

    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

  20. LLW (Low-Level Waste) Notes, Volume 13, Number 1, February 1998

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-02-01

    LLW Notes is a newsletter distributed to Low-Level Radioactive Waste Forum Participants and other state and compact officials. The LLW Forum provides an opportunity for state and compact officials to share information with one another and to exchange views with officials of federal agencies and other interested parties. This issue focuses on the following topics: DOI approves Ward Valley permit application; Project evidentiary hearings begin in Texas; and Summary judgment motions in California breach of contract action.

  1. Interim safety basis compliance matrix for Trenches 31 and 34

    Energy Technology Data Exchange (ETDEWEB)

    Ames, R.R.

    1994-12-30

    The tables provided in this document identify the specific requirements and basis for the administrative controls established in the Westinghouse Hanford Company (WHC) Solid Waste Burial Ground (SWBG) Interim Safety Basis (ISB) for operation of the Project W-025, Mixed Waste Lined Landfill (Trenches 31 and 34). The tables document the necessary controls and implementing procedures to ensure compliance with the requirements of the ISB. These requirements provide a basis for future Unreviewed Safety Questions (USQ) screening of applicable procedure changes, proposed physical modifications, tests, experiments, and occurrences. Table 1 provides the SWBG interim Operational Safety Requirements administrative controls matrix. The specific assumptions and commitments used in the safety analysis documents applicable to disposal of mixed wastes in Trenches 31 and 34 are provided in Table 2. Table 3 is provided to document the potential engineered and administrative mitigating features identified in the Preliminary Hazard Analysis (PHA) for disposal of mixed waste.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  3. Disposal of radioactive waste

    Science.gov (United States)

    Van Dorp, Frits; Grogan, Helen; McCombie, Charles

    The aim of radioactive and non-radioactive waste management is to protect man and the environment from unacceptable risks. Protection criteria for both should therefore be based on similar considerations. From overall protection criteria, performance criteria for subsystems in waste management can be derived, for example for waste disposal. International developments in this field are summarized. A brief overview of radioactive waste sorts and disposal concepts is given. Currently being implemented are trench disposal and engineered near-surface facilities for low-level wastes. For low-and intermediate-level waste underground facilities are under construction. For high-level waste site selection and investigation is being carried out in several countries. In all countries with nuclear programmes, the predicted performance of waste disposal systems is being assessed in scenario and consequence analyses. The influences of variability and uncertainty of parameter values are increasingly being treated by probabilistic methods. Results of selected performance assessments show that radioactive waste disposal sites can be found and suitable repositories can be designed so that defined radioprotection limits are not exceeded.

  4. SPECIAL ANALYSIS OF OPERATIONAL STORMWATER RUNOFF COVERS OVER SLIT TRENCHES

    Energy Technology Data Exchange (ETDEWEB)

    Collard, L; Luther Hamm, L

    2008-12-18

    Solid Waste Management (SWM) commissioned this Special Analysis (SA) to determine the effects of placing operational stormwater runoff covers (referred to as covers in the remainder of this document) over slit trench (ST) disposal units ST1 through ST7 (the center set of slit trenches). Previously the United States Department of Energy (DOE) entered into an agreement with the United States Environmental Protection Agency (EPA) and the South Carolina Department of Health and Environmental Control (SCDHEC) to place covers over Slit Trenches 1 and 2 to be able to continue disposing Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) solid waste (see USDOE 2008). Because the covers changed the operating conditions, DOE Order 435.1 (DOE 1999) required that an SA be performed to assess the impact. This Special Analysis has been prepared to determine the effects of placing covers over slit trenches at about years 5, 10 and 15 of the 30-year operational period. Because some slit trenches have already been operational for about 15 years, results from analyzing covers at 5 years and 10 years provide trend analysis information only. This SA also examined alternatives of covering Slit Trenches 1 and 2 with one cover and Slit Trenches 3 and 4 with a second cover versus covering them all with a single cover. Based on modeling results, minimal differences exist between covering Slit Trench groups 1-2 and 3-4 with two covers or one large cover. This SA demonstrates that placement of covers over slit trenches will slow the subsequent release and transport of radionuclides in the vadose zone in the early time periods (from time of placement until about 100 years). Release and transport of some radionuclides in the vadose zone beyond 100 years were somewhat higher than for the case without covers. The sums-of-fractions (SOFs) were examined for the current waste inventory in ST1 and ST2 and for estimated inventories at closure for ST3 through ST7. In all

  5. Phoenix Deepens Trenches on Mars

    Science.gov (United States)

    2008-01-01

    The Surface Stereo Imager on NASA's Phoenix Mars Lander took this false color image on Oct. 21, 2008, during the 145th Martian day, or sol, since landing. The bluish-white areas seen in these trenches are part of an ice layer beneath the soil. The trench on the upper left, called 'Dodo-Goldilocks,' is about 38 centimeters (15 inches) long and 4 centimeters (1.5 inches) deep. The trench on the right, called 'Upper Cupboard,' is about 60 centimeters (24 inches) long and 3 centimeters (1 inch) deep. The trench in the lower middle is called 'Stone Soup.' The Phoenix mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  6. Benthic carbon mineralization in hadal trenches

    DEFF Research Database (Denmark)

    Wenzhöfer, F.; Oguri, K.; Middelboe, Mathias;

    2016-01-01

    consumption rates and sediment characteristics from the trench axis of two contrasting trench systems in the Pacific Ocean; the Izu-Bonin Trench underlying mesotrophic waters and the Tonga Trench underlying oligotrophic waters. In situ oxygen consumption at the Izu-Bonin Trench axis site (9200 m; 746 +/- 103...... mu mol m(-2) d(-1); n=27) was 3-times higher than at the Tonga Trench axis site (10800 m; 225 +/- 50 pmol m(-2) d(-1); n=7) presumably reflecting the higher surface water productivity in the Northern Pacific. Comparing benthic O-2 consumption rates measured in the central hadal Tonga Trench...

  7. Composite analysis E-area vaults and saltstone disposal facilities

    Energy Technology Data Exchange (ETDEWEB)

    Cook, J.R.

    1997-09-01

    This report documents the Composite Analysis (CA) performed on the two active Savannah River Site (SRS) low-level radioactive waste (LLW) disposal facilities. The facilities are the Z-Area Saltstone Disposal Facility and the E-Area Vaults (EAV) Disposal Facility. The analysis calculated potential releases to the environment from all sources of residual radioactive material expected to remain in the General Separations Area (GSA). The GSA is the central part of SRS and contains all of the waste disposal facilities, chemical separations facilities and associated high-level waste storage facilities as well as numerous other sources of radioactive material. The analysis considered 114 potential sources of radioactive material containing 115 radionuclides. The results of the CA clearly indicate that continued disposal of low-level waste in the saltstone and EAV facilities, consistent with their respective radiological performance assessments, will have no adverse impact on future members of the public.

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

    Energy Technology Data Exchange (ETDEWEB)

    Gingerich, R.E. [Connecticut Hazardous Waste Management Service, Hartford, CT (United States)

    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.

  9. A decision tool for selecting trench cap designs

    Energy Technology Data Exchange (ETDEWEB)

    Paige, G.B.; Stone, J.J.; Lane, L.J. [USDA-ARS, Tucson, AZ (United States)] [and others

    1995-12-31

    A computer based prototype decision support system (PDSS) is being developed to assist the risk manager in selecting an appropriate trench cap design for waste disposal sites. The selection of the {open_quote}best{close_quote} design among feasible alternatives requires consideration of multiple and often conflicting objectives. The methodology used in the selection process consists of: selecting and parameterizing decision variables using data, simulation models, or expert opinion; selecting feasible trench cap design alternatives; ordering the decision variables and ranking the design alternatives. The decision model is based on multi-objective decision theory and uses a unique approach to order the decision variables and rank the design alternatives. Trench cap designs are evaluated based on federal regulations, hydrologic performance, cover stability and cost. Four trench cap designs, which were monitored for a four year period at Hill Air Force Base in Utah, are used to demonstrate the application of the PDSS and evaluate the results of the decision model. The results of the PDSS, using both data and simulations, illustrate the relative advantages of each of the cap designs and which cap is the {open_quotes}best{close_quotes} alternative for a given set of criteria and a particular importance order of those decision criteria.

  10. Novel trench gate field stop IGBT with trench shorted anode

    Science.gov (United States)

    Xudong, Chen; Jianbing, Cheng; Guobing, Teng; Houdong, Guo

    2016-05-01

    A novel trench field stop (FS) insulated gate bipolar transistor (IGBT) with a trench shorted anode (TSA) is proposed. By introducing a trench shorted anode, the TSA-FS-IGBT can obviously improve the breakdown voltage. As the simulation results show, the breakdown voltage is improved by a factor of 19.5% with a lower leakage current compared with the conventional FS-IGBT. The turn off time of the proposed structure is 50% lower than the conventional one with less than 9% voltage drop increased at a current density of 150 A/cm2. Additionally, there is no snapback observed. As a result, the TSA-FS-IGBT has a better trade-off relationship between the turn off loss and forward drop. Project supported by the National Natural Science Foundation of China (No. 61274080) and the Postdoctoral Science Foundation of China (No. 2013M541585).

  11. Interim characterization report for the 300 Area process trenches

    Energy Technology Data Exchange (ETDEWEB)

    Schalla, R.; Wallace, R.W.; Aaberg, R.L.; Airhart, S.P.; Bates, D.J.; Carlile, J.V.M.; Cline, C.S.; Dennison, D.I.; Freshley, M.D.; Heller, P.R.

    1988-09-01

    This document contains information on the results of the Hazardous Waste Ground-Water Monitoring Compliance Program characterization studies of wastes disposed of in the 300 Area process trenches. The characterization of the 300 Area process trenches has been conducted as part of an effort initiated in June 1985, when a facility-specific monitoring program was implemented. The characterization effort is part of a regulatory ground-water monitoring compliance program for hazardous chemicals on the Hanford Site. The characterization work described in this document represents an expanded ground-water monitoring compliance effort, and incorporates or refers to previous studies useful in characterizing the 300 Area. This document is primarily a compendium of technical information on the 300 Area; therefore, data interpretations are limited to the most obvious conclusions. Final conclusions will not be presented until the analysis of data is completed in September 1989. 48 refs., 25 figs., 4 tabs.

  12. Disposal configuration options for future uses of greater confinement disposal at the Nevada Test Site

    Energy Technology Data Exchange (ETDEWEB)

    Price, L. [Science Applications International Corp., Albuquerque, NM (United States)

    1994-09-01

    The US Department of Energy (DOE) is responsible for disposing of a variety of radioactive and mixed wastes, some of which are considered special-case waste because they do not currently have a clear disposal option. The DOE`s Nevada Field Office contracted with Sandia National Laboratories to investigate the possibility of disposing of some of this special-case waste at the Nevada Test Site (NTS). As part of this investigation, a review of a near-surface and subsurface disposal options that was performed to develop alternative disposal configurations for special-case waste disposal at the NTS. The criteria for the review included (1) configurations appropriate for disposal at the NTS; (2) configurations for disposal of waste at least 100 ft below the ground surface; (3) configurations for which equipment and technology currently exist; and (4) configurations that meet the special requirements imposed by the nature of special-case waste. Four options for subsurface disposal of special-case waste are proposed: mined consolidated rock, mined alluvium, deep pits or trenches, and deep boreholes. Six different methods for near-surface disposal are also presented: earth-covered tumuli, above-grade concrete structures, trenches, below-grade concrete structures, shallow boreholes, and hydrofracture. Greater confinement disposal (GCD) in boreholes at least 100 ft deep, similar to that currently practiced at the GCD facility at the Area 5 Radioactive Waste Management Site at the NTS, was retained as the option that met the criteria for the review. Four borehole disposal configurations are proposed with engineered barriers that range from the native alluvium to a combination of gravel and concrete. The configurations identified will be used for system analysis that will be performed to determine the disposal configurations and wastes that may be suitable candidates for disposal of special-case wastes at the NTS.

  13. Performance assessment for the disposal of low-level waste in the 200 West Area Burial Grounds

    Energy Technology Data Exchange (ETDEWEB)

    Wood, M.I.; Khaleel, R.; Rittmann, P.D.; Lu, A.H.; Finfrock, S.H.; DeLorenzo, T.H. [Westinghouse Hanford Co., Richland, WA (United States); Serne, R.J.; Cantrell, K.J. [Pacific Northwest Lab., Richland, WA (United States)

    1995-06-01

    This document reports the findings of a performance assessment (PA) analysis for the disposal of solid low-level radioactive waste (LLW) in the 200 West Area Low-Level Waste Burial Grounds (LLBG) in the northwest corner of the 200 West Area of the Hanford Site. This PA analysis is required by US Department of Energy (DOE) Order 5820.2A (DOE 1988a) to demonstrate that a given disposal practice is in compliance with a set of performance objectives quantified in the order. These performance objectives are applicable to the disposal of DOE-generated LLW at any DOE-operated site after the finalization of the order in September 1988. At the Hanford Site, DOE, Richland Operations Office (RL) has issued a site-specific supplement to DOE Order 5820.2A, DOE-RL 5820.2A (DOE 1993), which provides additiona I ce objectives that must be satisfied.

  14. Chemical, geological, and hydrological factors governing radionuclide migration from a formerly used seepage trench: a field study. Environmental Sciences Division publication No. 2202

    Energy Technology Data Exchange (ETDEWEB)

    Olsen, C.R.; Lowry, P.D.; Lee, S.Y.; Larsen, I.L.; Cutshall, N.H.

    1983-09-01

    A total of 3.2 x 10/sup 7/ L of intermediate-level liquid wastes (ILW) generated from routine Oak Ridge National Laboratory operations, were disposed in Trench 7 between 1962 and 1966. The disposed ILW contained about 10/sup 7/ GBq of fission nuclides (primarily /sup 137/Cs and /sup 90/Sr), activation products (primarily /sup 60/Co), actinides (primarily /sup 232/Th and /sup 238/U decay series nuclides), and transuranics (primarily /sup 241/Pu-/sup 241/Am). Gamma-log profiles of the wells near ILW Trench 7 indicate that the waste liquids seeped along discrete layers parallel to bedding and along the strikes of faults and folds. Although most of the radioactivity has been retained by sorption reactions with the trench fill, soils, and weathered bedrock, groundwater characteristics in the vicinity of ILW Trench 7 are still greatly influenced by the constituents of the waste liquids disposed two decades ago. Radionuclide concentrations in the groundwaters near the north end of ILW Trench 7 undergo seasonal variations, with the lowest activities occurring in fall and winter and the highest activities occurring in the spring and after prolonged rainstorm events. The rise in radioactivity in these wells correlates with a rise in the groundwater level and a concurrent increase in groundwater pH. Although ILW Trench 7 has worked effectively to retain most of the disposed radioactivity, two suspected transport pathways from the trench to a nearby seep area have been identified and both appear to be associated with fault zones. Only the pathway near the north end of the trench appears to be leaching alkalinity and thus affecting the retention capacity for /sup 90/Sr. A groundwater interceptor at the north end of ILW Trench 7 is one possible remedial action to help maintain a dry alkaline environment and ensure the integrity of the trench for nuclide retention.

  15. 'Snow White' Trench After Scraping

    Science.gov (United States)

    2008-01-01

    This view from the Surface Stereo Imager on NASA's Phoenix Mars Lander shows the trench informally named 'Snow White.' This image was taken after a series of scrapings by the lander's Robotic Arm on the 58th Martian day, or sol, of the mission (July 23, 2008). The scrapings were done in preparation for collecting a sample for analysis from a hard subsurface layer where soil may contain frozen water. The trench is 4 to 5 centimeters (about 2 inches) deep, about 23 centimeters (9 inches) wide and about 60 centimeters (24 inches) long. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  16. 40 CFR 265 interim status indicator-evaluation ground-water monitoring plan for the 216-B-63 trench

    Energy Technology Data Exchange (ETDEWEB)

    Bjornstad, B.N.; Dudziak, S.

    1989-03-01

    This document outlines a ground-water monitoring plan for the 216-B-63 trench located in the northeast corner of the 200-East Area on the Hanford Site in southeastern Washington State. It has been determined that hazardous materials (corrosives) were disposed of to the trench during past operations. Installation of an interim-status ground-water monitoring system is required to determine whether hazardous chemicals are leaching to the ground water from beneath the trench. This document summarizes the existing data that are available from near the 216-B-63 trench and presents a plan to determine the extent of ground-water contamination, if any, derived from the trench. The plan calls for the installation of four new monitoring wells located near the west end of the trench. These wells will be used to monitor ground-water levels and water quality immediately adjacent to the trench. Two existing RCRA monitoring wells, which are located near the trench and hydraulically upgradient of it, will be used as background wells. 46 refs., 15 figs., 12 tabs.

  17. WRAP low level waste restricted waste management (LLW RWM) glovebox acceptance test report

    Energy Technology Data Exchange (ETDEWEB)

    Leist, K.J.

    1997-11-24

    On April 22, 1997, the Low Level Waste Restricted Waste Management (LLW RWM) glovebox was tested using acceptance test procedure 13027A-87. Mr. Robert L. Warmenhoven served as test director, Mr. Kendrick Leist acted as test operator and test witness, and Michael Lane provided miscellaneous software support. The primary focus of the glovebox acceptance test was to examine glovebox control system interlocks, operator Interface Unit (OIU) menus, alarms, and messages. Basic drum port and lift table control sequences were demonstrated. OIU menus, messages, and alarm sequences were examined, with few exceptions noted. Barcode testing was bypassed, due to the lack of installed equipment as well as the switch from basic reliance on fixed bar code readers to the enhanced use of portable bar code readers. Bar code testing was completed during performance of the LLW RWM OTP. Mechanical and control deficiencies were documented as Test Exceptions during performance of this Acceptance Test. These items are attached as Appendix A to this report.

  18. Current practices for maintaining occupational exposures ALARA at low-level waste disposal sites

    Energy Technology Data Exchange (ETDEWEB)

    Hadlock, D.E.; Herrington, W.N.; Hooker, C.D.; Murphy, D.W.; Gilchrist, R.L.

    1983-12-01

    The United States Nuclear Regulatory Commission contracted with Pacific Northwest Laboratory (PNL) to provide technical assistance in establishing operational guidelines, with respect to radiation control programs and methods of minimizing occupational radiation exposure, at Low-Level Waste (LLW) disposal sites. The PNL, through site visits, evaluated operations at LLW disposal sites to determine the adequacy of current practices in maintaining occupational exposures as low as is reasonably achievable (ALARA). The data sought included the specifics of: ALARA programs, training programs, external exposure control, internal exposure control, respiratory protection, surveillance, radioactive waste management, facilities and equipment, and external dose analysis. The results of the study indicated the following: The Radiation Protection and ALARA programs at the three commercial LLW disposal sites were observed to be adequate in scope and content compared to similar programs at other types of nuclear facilities. However, it should be noted that there were many areas that could be improved upon to help ensure the health and safety of occupationally exposed individuals.

  19. Low level tank waste disposal study

    Energy Technology Data Exchange (ETDEWEB)

    Mullally, J.A.

    1994-09-29

    Westinghouse Hanford Company (WHC) contracted a team consisting of Los Alamos Technical Associates (LATA), British Nuclear Fuel Laboratories (BNFL), Southwest Research Institute (SwRI), and TRW through the Tank Waste Remediation System (TWRS) Technical Support Contract to conduct a study on several areas concerning vitrification and disposal of low-level-waste (LLW). The purpose of the study was to investigate how several parameters could be specified to achieve full compliance with regulations. The most restrictive regulation governing this disposal activity is the National Primary Drinking Water Act which sets the limits of exposure to 4 mrem per year for a person drinking two liters of ground water daily. To fully comply, this constraint would be met independently of the passage of time. In addition, another key factor in the investigation was the capability to retrieve the disposed waste during the first 50 years as specified in Department of Energy (DOE) Order 5820.2A. The objective of the project was to develop a strategy for effective long-term disposal of the low-level waste at the Hanford site.

  20. DOSE ASSESSMENT OF THE FINAL INVENTORIES IN CENTER SLIT TRENCHES ONE THROUGH FIVE

    Energy Technology Data Exchange (ETDEWEB)

    Collard, L.; Hamm, L.; Smith, F.

    2011-05-02

    In response to a request from Solid Waste Management (SWM), this study evaluates the performance of waste disposed in Slit Trenches 1-5 by calculating exposure doses and concentrations. As of 8/19/2010, Slit Trenches 1-5 have been filled and are closed to future waste disposal in support of an ARRA-funded interim operational cover project. Slit Trenches 6 and 7 are currently in operation and are not addressed within this analysis. Their current inventory limits are based on the 2008 SA and are not being impacted by this study. This analysis considers the location and the timing of waste disposal in Slit Trenches 1-5 throughout their operational life. In addition, the following improvements to the modeling approach have been incorporated into this analysis: (1) Final waste inventories from WITS are used for the base case analysis where variance in the reported final disposal inventories is addressed through a sensitivity analysis; (2) Updated K{sub d} values are used; (3) Area percentages of non-crushable containers are used in the analysis to determine expected infiltration flows for cases that consider collapse of these containers; (4) An updated representation of ETF carbon column vessels disposed in SLIT3-Unit F is used. Preliminary analyses indicated a problem meeting the groundwater beta-gamma dose limit because of high H-3 and I-129 release from the ETF vessels. The updated model uses results from a recent structural analysis of the ETF vessels indicating that water does not penetrate the vessels for about 130 years and that the vessels remain structurally intact throughout the 1130-year period of assessment; and (5) Operational covers are included with revised installation dates and sets of Slit Trenches that have a common cover. With the exception of the modeling enhancements noted above, the analysis follows the same methodology used in the 2008 PA (WSRC, 2008) and the 2008 SA (Collard and Hamm, 2008). Infiltration flows through the vadose zone are

  1. Digging in 'Snow White' Trench

    Science.gov (United States)

    2008-01-01

    This image was acquired by NASA's Phoenix Mars Lander's Surface Stereo Imager on the 44th Martian day of the mission, or Sol 43 (July 7, 2008), after the May 25, 2008, landing, showing the current sample scraping area in the trench informally called 'Snow White.' The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is led by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  2. Standardization of DOE Disposal Facilities Waste Acceptance Process

    Energy Technology Data Exchange (ETDEWEB)

    SHRADER, T.; MACBETH, P.

    2002-01-01

    On February 25, 2000, the US. Department of Energy (DOE) issued the Record of Decision (ROD) for the Waste Management Programmatic Environmental Impact Statement (WM PEIS) for low-level and mixed low-level wastes (LLW/ MLLW) treatment and disposal. The ROD designated the disposal sites at Hanford and the Nevada Test Site (NTS) to dispose of LLWMLLW from sites without their own disposal facilities. DOE's Richland Operations Office (RL) and the National Nuclear Security Administration's Nevada Operations Office (NV) have been charged with effectively implementing the ROD. To accomplish this task NV and RL, assisted by their operating contractors Bechtel Nevada (BN), Fluor Hanford (FH), and Bechtel Hanford (BH) assembled a task team to systematically map out and evaluate the current waste acceptance processes and develop an integrated, standardized process for the acceptance of LLWMLLW. A structured, systematic, analytical process using the Six Sigma system identified disposal process improvements and quantified the associated efficiency gains to guide changes to be implemented. The review concluded that a unified and integrated Hanford/NTS Waste Acceptance Process would be a benefit to the DOE Complex, particularly the waste generators. The Six Sigma review developed quantitative metrics to address waste acceptance process efficiency improvements, and provides an initial look at development of comparable waste disposal cost models between the two disposal sites to allow quantification of the proposed improvements.

  3. Performance assessment for a hypothetical low-level waste disposal facility

    Energy Technology Data Exchange (ETDEWEB)

    Smith, C.S.; Rohe, M.J.; Ritter, P.D. [and others

    1997-01-01

    Disposing of low-level waste (LLW) is a concern for many states throughout the United States. A common disposal method is below-grade concrete vaults. Performance assessment analyses make predictions of contaminant release, transport, ingestion, inhalation, or other routes of exposure, and the resulting doses for various disposal methods such as the below-grade concrete vaults. Numerous assumptions are required to simplify the processes associated with the disposal facility to make predictions feasible. In general, these assumptions are made conservatively so as to underestimate the performance of the facility. The objective of this report is to describe the methodology used in conducting a performance assessment for a hypothetical waste facility located in the northeastern United States using real data as much as possible. This report consists of the following: (a) a description of the disposal facility and site, (b) methods used to analyze performance of the facility, (c) the results of the analysis, and (d) the conclusions of this study.

  4. Overview of EPA`s environmental standards for the land disposal

    Energy Technology Data Exchange (ETDEWEB)

    Gruhlke, J.M.; Galpin, F.L.; Holcomb, W.F. [Environmental Protection Agency, Washington, DC (United States). Office of Radiation Programs

    1989-11-01

    The Environmental Protection Agency (EPA) program to develop proposed generally applicable environmental standards for land disposal of low-level radioactive waste and certain naturally occurring and accelerator-produced radioactive wastes has been completed. The elements of the proposed standards include the following: (1) exposure limits for pre-disposal management and storage operations, (2) criteria for other regulatory agencies to follow in specifying wastes that are Below Regulatory Concern (BRC), (3) post-disposal exposure limits, (4) ground water protection requirements, and (5) qualitative implementation requirements. In addition to covering those radioactive wastes subject to the Atomic Energy Act (AEA), the Agency also intends to propose a standard to require the disposal of high concentration, Naturally occurring and Accelerator-produced Radioactive Materials (NARM) wastes exceeding 2 nCi/g, excluding a few consumer items, in regulated LLW disposal facilities.

  5. Performance assessment for a hypothetical low-level waste disposal facility

    Energy Technology Data Exchange (ETDEWEB)

    Smith, C.S.; Rohe, M.J.; Ritter, P.D. [and others

    1997-01-01

    Disposing of low-level waste (LLW) is a concern for many states throughout the United States. A common disposal method is below-grade concrete vaults. Performance assessment analyses make predictions of contaminant release, transport, ingestion, inhalation, or other routes of exposure, and the resulting doses for various disposal methods such as the below-grade concrete vaults. Numerous assumptions are required to simplify the processes associated with the disposal facility to make predictions feasible. In general, these assumptions are made conservatively so as to underestimate the performance of the facility. The objective of this report is to describe the methodology used in conducting a performance assessment for a hypothetical waste facility located in the northeastern United States using real data as much as possible. This report consists of the following: (a) a description of the disposal facility and site, (b) methods used to analyze performance of the facility, (c) the results of the analysis, and (d) the conclusions of this study.

  6. Challenges in hardening technologies using shallow-trench isolation

    Energy Technology Data Exchange (ETDEWEB)

    Shaneyfelt, M.R.; Dodd, P.E.; Draper, B.L.; Flores, R.S.

    1998-02-01

    Challenges related to radiation hardening CMOS technologies with shallow-trench isolation are explored. Results show that trench hardening can be more difficult than simply replacing the trench isolation oxide with a hardened field oxide.

  7. Preliminary Closure Plan for the Immobilized Low Activity Waste (ILAW) Disposal Facility

    Energy Technology Data Exchange (ETDEWEB)

    BURBANK, D.A.

    2000-08-31

    This document describes the preliminary plans for closure of the Immobilized Low-Activity Waste (ILAW) disposal facility to be built by the Office of River Protection at the Hanford site in southeastern Washington. The facility will provide near-surface disposal of up to 204,000 cubic meters of ILAW in engineered trenches with modified RCRA Subtitle C closure barriers.

  8. Disposable rabbit

    Science.gov (United States)

    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.

  9. Disposal rabbit

    Science.gov (United States)

    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.

  10. A Novel and Cost Effective Approach to the Decommissioning and Decontamination of Legacy Glove Boxes - Minimizing TRU Waste and Maximizing LLW Waste - 13634

    Energy Technology Data Exchange (ETDEWEB)

    Pancake, Daniel; Rock, Cynthia M.; Creed, Richard [Argonne National Laboratory, 9700 South Cass Avenue, Lemont, IL 60439 (United States); Donohoue, Tom; Martin, E. Ray; Mason, John A. [ANTECH Corporation 9050 Marshall Court, Westminster, CO, 80031 (United States); Norton, Christopher J.; Crosby, Daniel [Environmental Alternatives, Inc., 149 Emerald Street, Suite R, Keene, NH 03431 (United States); Nachtman, Thomas J. [InstaCote, Inc., 160 C. Lavoy Road, Erie, MI, 48133 (United States)

    2013-07-01

    This paper describes the process of decommissioning two gloveboxes at the Argonne National Laboratory (ANL) that were employed for work with plutonium and other radioactive materials. The decommissioning process involved an initial phase of clearing tools and materials from the glove boxes and disconnecting them from the laboratory infrastructure. The removed materials, assessed as Transuranic (TRU) waste, were packaged into 55 gallon (200 litre) drums and prepared for ultimate disposal at the Waste Isolation Pilot Plant (WIPP) at Carlsbad New Mexico. The boxes were then sampled to determine the radioactive contents by means of smears that were counted with alpha and beta detectors to determine the residual surface contamination, especially in terms of alpha particle emitters that are an indicator of TRU activity. Paint chip samples were also collected and sent for laboratory analysis in order to ascertain the radioactive contamination contributing to the TRU activity as a fixed contamination. The investigations predicted that it may be feasible to reduce the residual surface contamination and render the glovebox structure low level waste (LLW) for disposal. In order to reduce the TRU activity a comprehensive decontamination process was initiated using chemical compounds that are particularly effective for lifting and dissolving radionuclides that adhere to the inner surfaces of the gloveboxes. The result of the decontamination process was a reduction in the TRU surface activity on the inner surfaces of the gloveboxes by four orders of magnitude in terms of disintegrations per unit area (DPA). The next phase of the process involved a comprehensive assay of the gloveboxes using a combination of passive neutron and gamma ray scintillation detectors and a shielded and collimated high purity Germanium (HPGe) gamma ray detector. The HPGe detector was used to obtain gamma ray spectra for a variety of measurement positions within the glovebox. The spectra were used to

  11. Source inventory for Department of Energy solid low-level radioactive waste disposal facilities: What it means and how to get one of your own

    Energy Technology Data Exchange (ETDEWEB)

    Smith, M.A. [Science Applications International Corp., Oak Ridge, TN (United States). Environmental Compliance Group

    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.

  12. Backfilling of trenches exposed to waves

    DEFF Research Database (Denmark)

    Hjelmager Jensen, Jacob; Fredsøe, Jørgen

    1997-01-01

    This paper treats the numerical prediction of initial and long-term morphology of small pipeline trenches. For this purpose a refined flow and sediment transport description is applied such that the entire mathematical problem is formulated and solved on a curvilinear grid using a k - ε turbulence...... of a particle in waves and L the trench length, is investigated in detail, and an optimal KC-number for the backfilling rate is found. Coherent structures in the non-uniform unsteady trench-flow are shown to dominate the deposition rate when present. The importance of a detailed description of the flow...

  13. Universal trench design method for a high-voltage SOI trench LDMOS

    Institute of Scientific and Technical Information of China (English)

    Hu Xiarong; Zhang Bo; Luo Xiaorong; Li Zhaoji

    2012-01-01

    The design method for a high-voltage SOl trench LDMOS for various trench permittivities,widths and depths is introduced.A universal method for efficient design is presented for the first time,taking the trade-off between breakdown voltage (BV) and specific on-resistance (Rs,on) into account.The high-k (relative permittivity)dielectric is suitable to fill a shallow and wide trench while the low-k dielectric is suitable to fill a deep and narrow trench.An SOI LDMOS with a vacuum trench in the drift region is also discussed.Simulation results show that the high FOM BV2/Rs,on can be achieved with a trench filled with the low-k dielectric due to its shortened cell-pitch.

  14. Waste disposal

    CERN Multimedia

    2006-01-01

    We should like to remind you that you can have all commonplace, conventional waste (combustible, inert, wood, etc.) disposed of by the TS-FM Group. Requests for the removal of such waste should be made by contacting FM Support on tel. 77777 or by e-mail (Fm.Support@cern.ch). For requests to be acted upon, the following information must be communicated to FM Support: budget code to be debited for the provision and removal of the skip / container. type of skip required (1m3, 4 m3, 7 m3, 15 m3, 20 m3, 30 m3). nature of the waste to be disposed of (bulky objects, cardboard boxes, etc.). building concerned. details of requestor (name, phone number, department, group, etc.). We should also like to inform you that the TS-FM Group can arrange for waste to be removed from work-sites for firms under contract to CERN, provided that the prior authorisation of the CERN Staff Member in charge of the contract is obtained and the relevant disposal/handling charges are paid. You are reminded that the selective sorting o...

  15. Waste disposal

    CERN Multimedia

    2006-01-01

    We should like to remind you that you can have all commonplace, conventional waste (combustible, inert, wood, etc.) disposed of by the TS-FM Group. Requests for the removal of such waste should be made by contacting FM Support on tel. 77777 or by e-mail (Fm.Support@cern.ch). For requests to be acted upon, the following information must be communicated to FM Support: budget code to be debited for the provision and removal of the skip / container; type of skip required (1m3, 4 m3, 7 m3, 15 m3, 20 m3, 30 m3); nature of the waste to be disposed of (bulky objects, cardboard boxes, etc.); building concerned; details of requestor (name, phone number, department, group, etc.). We should also like to inform you that the TS-FM Group can arrange for waste to be removed from work-sites for firms under contract to CERN, provided that the prior authorisation of the CERN Staff Member in charge of the contract is obtained and the relevant disposal/handling charges are paid. You are reminded that the selective sorting...

  16. Revised ground-water monitoring compliance plan for the 300 area process trenches

    Energy Technology Data Exchange (ETDEWEB)

    Schalla, R.; Aaberg, R.L.; Bates, D.J.; Carlile, J.V.M.; Freshley, M.D.; Liikala, T.L.; Mitchell, P.J.; Olsen, K.B.; Rieger, J.T.

    1988-09-01

    This document contains ground-water monitoring plans for process-water disposal trenches located on the Hanford Site. These trenches, designated the 300 Area Process Trenches, have been used since 1973 for disposal of water that contains small quantities of both chemicals and radionuclides. The ground-water monitoring plans contained herein represent revision and expansion of an effort initiated in June 1985. At that time, a facility-specific monitoring program was implemented at the 300 Area Process Trenches as part of a regulatory compliance effort for hazardous chemicals being conducted on the Hanford Site. This monitoring program was based on the ground-water monitoring requirements for interim-status facilities, which are those facilities that do not yet have final permits, but are authorized to continue interim operations while engaged in the permitting process. The applicable monitoring requirements are described in the Resource Conservation and Recovery Act (RCRA), 40 CFR 265.90 of the federal regulations, and in WAC 173-303-400 of Washington State's regulations (Washington State Department of Ecology 1986). The program implemented for the process trenches was designed to be an alternate program, which is required instead of the standard detection program when a facility is known or suspected to have contaminated the ground water in the uppermost aquifer. The plans for the program, contained in a document prepared by the US Department of Energy (USDOE) in 1985, called for monthly sampling of 14 of the 37 existing monitoring wells at the 300 Area plus the installation and sampling of 2 new wells. 27 refs., 25 figs., 15 tabs.

  17. 284-E Powerhouse trench engineering study

    Energy Technology Data Exchange (ETDEWEB)

    Crane, A.F.

    1997-01-20

    This document provides the basis for future use of the 284-E Powerhouse Trench as a transport conduit for effluents discharged from the 284-E Powerhouse in accordance with the requirements of the State Waste Discharge Permit, ST 4502.

  18. Mariana Trench Bathymetric Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) created a bathymetric digital elevation model (DEM) for the Mariana Trench and adjacent seafloor in the Western...

  19. Recent sediment dynamics in hadal trenches

    DEFF Research Database (Denmark)

    Turnewitsch, Robert; Falahat, Saeed; Stehlikova, Jirina

    2014-01-01

    by evaluating ratios of measured (sediment-derived) and expected (water-column-derived) sedimentary inventories of the naturally occurring and radioactive particulate-matter tracer Pb-210(xs). The sites comprise a broad range of surface-ocean productivity and physical-oceanographic regimes. Across the five...... trench-axis settings the inventory ratio varies between 0.5 and 4.1, with four trench-axis settings having ratios > 1 (sediment focussing) and one trench-axis setting a ratio ... but significant influence on particulate-matter dynamics and food supply in hadal trenches in particular, but possibly also in the deep seas in general. A mechanism for the influence of internal tides on sediment dynamics is proposed. (C) 2014 Elsevier Ltd. All rights reserved....

  20. Diode having trenches in a semiconductor region

    Science.gov (United States)

    Palacios, Tomas Apostol; Lu, Bin; Matioli, Elison de Nazareth

    2016-03-22

    An electrode structure is described in which conductive regions are recessed into a semiconductor region. Trenches may be formed in a semiconductor region, such that conductive regions can be formed in the trenches. The electrode structure may be used in semiconductor devices such as field effect transistors or diodes. Nitride-based power semiconductor devices are described including such an electrode structure, which can reduce leakage current and otherwise improve performance.

  1. Modeling of LNG spills into trenches.

    Science.gov (United States)

    Gavelli, Filippo; Chernovsky, Melissa K; Bullister, Edward; Kytomaa, Harri K

    2010-08-15

    A new method for the analysis of LNG spills into trenches has been developed to quantify vapor dispersion hazard distances. The model uses three steps to capture the behavior of an LNG spill into a trench. The first is to analytically calculate the evolving LNG flow, the second to calculate the vaporization rate along the trench, and the third is to calculate the dispersion of the vapors using a CFD model that has been validated for this application in the presence of complex geometries. This paper presents case studies that show the effect of wind perpendicular and parallel to the large aspect ratio trenches on vapor dispersion. The case studies also demonstrate the effect of complex terrain and obstacles such as vapor fences on vapor dispersion. The simulations show that wind direction relative to the trench has a significant effect on cloud shape, height, and maximum downwind distance. The addition of vapor fences to mitigate vapor dispersion hazards from an LNG spill into the LNG containment trench is shown to be effective.

  2. Hazard Classification of the Remote Handled Low-Level Waste Disposal Facility

    Energy Technology Data Exchange (ETDEWEB)

    Boyd D. Christensen

    2012-05-01

    The Battelle Energy Alliance (BEA) at the Idaho National Laboratory (INL) is constructing a new facility to replace remote-handled low-level radioactive waste disposal capability for INL and Naval Reactors Facility operations. Current disposal capability at the Radioactive Waste Management Complex (RWMC) will continue until the facility is full or closed for remediation (estimated at approximately fiscal year 2015). Development of a new onsite disposal facility is the highest ranked alternative and will provide RH-LLW disposal capability and will ensure continuity of operations that generate RH-LLW for the foreseeable future. As a part of establishing a safety basis for facility operations, the facility will be categorized according to DOE-STD-1027-92. This classification is important in determining the scope of analyses performed in the safety basis and will also dictate operational requirements of the completed facility. This paper discusses the issues affecting hazard classification in this nuclear facility and impacts of the final hazard categorization.

  3. Celecoxib and LLW-3-6 Reduce Survival of Human Glioma Cells Independently and Synergistically with Sulfasalazine.

    Science.gov (United States)

    Yerokun, Tokunbo; Winfield, Leyte L

    2015-12-01

    Gliomas are among the most commonly diagnosed central nervous system tumors. Celecoxib has been utilized with success in the treatment of several types of cancer, including gliomas. The present study examined the antiproliferative effects of celecoxib and its benzimidazole-based analog, LLW-3-6, when used as co-treatment with sulfasalazine against human glioma LN18 cells. At 48-h treatment, the glioma cells maintained 60% viability in the presence of celecoxib or LLW-3-6 at the maximum concentration tested (40 μM). Co-treatment of glioma cells under a non-lethal dose (50 μM) of sulfasalazine and either celecoxib or LLW-3-6 (administered at different concentrations) resulted in improved inhibition of cell viability. The concentration of the molecules required to reduce cell growth in the combined treatment was significantly less than that needed when either molecule was administered independently. Based on computational values, LLW-3-6 has physiochemical characteristics that should allow for improved bioavailability in comparison to that of celecoxib.

  4. Removal of radioactive caesium from low level radioactive waste (LLW) streams using cobalt ferrocyanide impregnated organic anion exchanger.

    Science.gov (United States)

    Valsala, T P; Roy, S C; J G Shah; Gabriel, J; Raj, Kanwar; Venugopal, V

    2009-07-30

    The volumes of low level waste (LLW) generated during the operation of nuclear reactor are very high and require a concentration step before suitable matrix fixation. The volume reduction (concentration) is achieved either by co-precipitating technique or by the use of highly selective sorbents and ion exchange materials. The present study details the preparation of cobalt ferrocyanide impregnated into anion exchange resin and its evaluation with respect to removal of Cs in LLW streams both in column mode and batch mode operations. The Kd values of the prepared exchanger materials were found to be very good in actual reactor LLW solutions also. It was observed that the exchanger performed very well in the pH range of 3-9. A batch size of 6 g l(-1) of the exchanger was enough to give satisfactory decontamination for Cs in actual reactor LLW streams. The lab scale and pilot plant scale performance of the exchanger material in both batch mode and column mode operations was very good.

  5. Evaluation of isotope migration: land burial. Water chemistry at commercially operated low-level radioactive waste disposal sites. Progress report No. 7, October--December 1977

    Energy Technology Data Exchange (ETDEWEB)

    Colombo, P.; Weiss, A. J.; Francis, A. J.

    1978-01-01

    Trench water samples from the commercial low-level radioactive waste disposal sites at Maxey Flats, Kentucky, and West Valley, New York, were collected, and the bacterial populations were enumerated. The range of bacterial populations in six trench water samples were 400 to 24,000 aerobic and 90 to 15,000 anaerobic bacteria/ml. Most of the bacteria isolated from the anaerobic culture plates were facultative anaerobes, although a few strict anaerobes were also present. Mixed bacterial populations isolated from the trench waters were able to grow anaerobically utilizing the carbon and nitrogen sources present in the trench waters. Trench waters supplemented with mineral salts supported only a modest increase in growth of these bacteria. The results of this study indicate that bacteria are active in the trenches, and the radioactivity and organic compounds present in the trenches are not toxic to these bacteria.

  6. Integrated Disposal Facility FY2011 Glass Testing Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    Pierce, Eric M.; Bacon, Diana H.; Kerisit, Sebastien N.; Windisch, Charles F.; Cantrell, Kirk J.; Valenta, Michelle M.; Burton, Sarah D.; Westsik, Joseph H.

    2011-09-29

    Pacific Northwest National Laboratory was contracted by Washington River Protection Solutions, LLC to provide the technical basis for estimating radionuclide release from the engineered portion of the disposal facility (e.g., source term). Vitrifying the low-activity waste at Hanford is expected to generate over 1.6 x 10{sup 5} m{sup 3} of glass (Certa and Wells 2010). The volume of immobilized low-activity waste (ILAW) at Hanford is the largest in the DOE complex and is one of the largest inventories (approximately 8.9 x 10{sup 14} Bq total activity) of long-lived radionuclides, principally {sup 99}Tc (t{sub 1/2} = 2.1 x 10{sup 5}), planned for disposal in a low-level waste (LLW) facility. Before the ILAW can be disposed, DOE must conduct a performance assessment (PA) for the Integrated Disposal Facility (IDF) that describes the long-term impacts of the disposal facility on public health and environmental resources. As part of the ILAW glass testing program PNNL is implementing a strategy, consisting of experimentation and modeling, in order to provide the technical basis for estimating radionuclide release from the glass waste form in support of future IDF PAs. The purpose of this report is to summarize the progress made in fiscal year (FY) 2011 toward implementing the strategy with the goal of developing an understanding of the long-term corrosion behavior of low-activity waste glasses.

  7. Emplacement Guidance for Criticality Safety in Low-Level-Waste Disposal

    Energy Technology Data Exchange (ETDEWEB)

    Elam, K.R.

    2001-06-23

    The disposal of low-level radioactive waste (LLW) containing special nuclear material (SNM) presents some unusual challenges for LLW disposal site operators and regulators. Radiological concerns associated with the radioactive decay of the SNM are combined with concerns associated with the avoidance of a nuclear criticality both during handling and after disposal of the waste. Currently, there are three operating LLW disposal facilities: Envirocare, Barnwell, and Richland. All these facilities are located in U.S. Nuclear Regulatory Commission (NRC) Agreement States and are regulated by their respective state: Utah, South Carolina, and Washington. As such, the amount of SNM that can be possessed by each of these facilities is limited to the 10 CFR Part 150 limits (i.e., 350 g of uranium-235, 200 g of uranium-233, and 200 g of Pu, with the sum-of-fractions rule applying), unless an exemption is issued. NRC has applied these SNM possession limits to above-ground possession. The purpose of this report is to provide data which could demonstrate that SNM waste at emplacement will not cause a nuclear criticality accident. Five different SNM isotopic compositions were studied: 100 wt% enriched uranium, 10 wt% enriched uranium, uranium-233, plutonium-239, and an isotopic mixture of plutonium (76 wt% plutonium-239, 12 wt% plutonium-240, and 12 wt% plutonium-241). Three different graded-approach methods are presented. The first graded-approach method is the most conservative and may be applicable to facilities that dispose of very low areal densities of SNM, or dispose of material with a low average enrichment. It relies on the calculation of average areal density or on the average enrichment of SNM. The area over which averaging may be performed is also specified, but the emplacement depth is not constrained. The second graded-approach method relies on limiting the average concentration by weight of SNM in the waste, and on limiting the depth of the emplacement. This method

  8. T-Rex system for operation in TRU, LLW, and hazardous zones

    Energy Technology Data Exchange (ETDEWEB)

    Kline, H.M. (EG and G Idaho, Inc., Idaho Falls, ID (United States)); Andreychek, T.P.; Beeson, B.K. (Martin Marietta Corp., Baltimore, MD (United States). Aero and Naval Systems)

    1993-01-01

    There are a large number of sites around the world containing TRU (transuranic) waste, low level waste (LLW), and hazardous areas that require teleoperated, heavy lift manipulators with long reach and high precision to handle the materials stored there. Teleoperation of the equipment is required to reduce the risk to operating personnel to as-low-as-reasonably-achievable (ALARA) levels. The Transuranic Storage Area Remote Excavator system (T-Rex) is designed to fill this requirement at low cost through the integration of a production front shovel excavator with a control system, local and remote operator control stations, a closed-circuit television system (CCTV), multiple end effectors and a quick-change system. This paper describes the conversion of an off-the-shelf excavator with a hydraulic control system, the integration of an onboard remote control system, vision system, and the design of a remote control station.

  9. Grout testing and characterization for shallow-land burial trenches at the Idaho National Engineering Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Tallent, O.K.; Sams, T.L.; Tamura, T.; Godsey, T.T.; Francis, C.L.; McDaniel, E.W.

    1986-10-01

    An investigation was conducted to develop grout formulations suitable for in situ stabilization of low-level and transuranic (TRU) waste in shallow-land burial trenches at Idaho National Engineering Laboratory (INEL). The acceptabilities of soil, ordinary particulate, and fine particulate grouts were evaluated based on phase separation, compressive strength, freeze/thaw, penetration resistance, rheological, water permeability, column, and other tests. Soil grouts with soil-to-cement weight ratios from 0.91 to 1.60 were found to be suitable for open trench or drum disposal. Ordinary particulate grouts containing type I,II Portland cement, class C fly ash, bentonite, water, and a fluidizer were formulated to fill large voids within the soil/waste matrix of a closed shallow-land burial trench. Fine particulate grouts containing fine (mean particle size, 9.6 m) cement and water were formulated to fill smaller voids and to establish a grout-soil barrier to prevent water intrusion into the grouted waste trench. Solution, or chemical grouts, were evaluated as possible substitutes for the fine particulate grouts.

  10. Evaluation of isotope migration: land burial. Water chemistry at commercially operated low-level radioactive waste disposal sites. Progress report No. 6, July--September 1977. [Maxey Flats, Kentucky

    Energy Technology Data Exchange (ETDEWEB)

    Colombo, P.; Weiss, A. J.; Francis, A. J.

    1978-04-01

    A survey of the Maxey Flats, Kentucky, low-level radioactive waste disposal site was conducted to obtain an overview of the radioactivity in the trench waters for the purpose of selecting specific trenches for comprehensive study. Water samples collected from trenches and wells were analyzed for specific conductance, pH, temperature, dissolved organic carbon, tritium, gross alpha, gross beta, and gamma radioactivities. The results indicate that there are large differences in the composition of trench waters at the site. Several trenches, that represent extreme and average values of the major parameters measured, have been tentatively selected for further study. 10 fig, 6 tables.

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

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, P.D.; Rockhold, M.L.; Nichols, W.E.; Gee, G.W. [Pacific Northwest Lab., Richland, WA (United States)

    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. Recommended Radiation Protection Practices for Low-Level Waste Disposal Sites

    Energy Technology Data Exchange (ETDEWEB)

    Hadlock, D. E.; Hooker, C. D.; Herrington, W. N.; Gilchrist, R. L.

    1983-12-01

    The United States Nuclear Regulatory Commission contracted with Pacific Northwest Laboratory (PNL) to provide technical assistance in estsblishing operational guidelines, with respect to radiation control programs and methods of minimizing occupational radiation exposure, at Low-Level Waste (LLW) dis- posal sites. The PNL, through site visits, evaluated operations at LLW dis- posal sites to determine the adequacy of current practices in maintaining occupational exposures as low as is reasonably achievable (ALARA). The data sought included the specifics of: ALARA programs, training programs, external exposure control , internal exposure control , respiratory protection, survei 1 - lance, radioactive waste management, facilities and equipment, and external dose analysis. The results of the study indicated the following: The Radiation Protection and ALARA programs at the three commercial LLW disposal sites were observed to be adequate in scope and content compared to similar programs at other types of nuclear facilities. However, it should be noted that there were many areas that could be improved upon to help ensure the health and safety of the occupa- tionally exposed individuals. As a result, radiation protection practices were recommended with related rationales in order to reduce occupational exposures as far below specified radiation limits as is reasonably achievable. In addition, recommendations were developed for achieving occupational exposure ALARA under the Regulatory Requirements issued in 10 CFR Part 61.

  13. Chicxulub Ejecta Impact Trenches And Terminal Impact

    Science.gov (United States)

    Page, R. L.

    2013-05-01

    DISCOVERY During a Pacific voyage from E. Australia to the US on a small sailing research vessel what appears to be two Chicxulub impact trenches were discovered in the ocean floor at depths of 4,627m and 3,519m. DESCRIPTION Trench A begins at a depth of 4,627m, 704km from the Chicxulub impact and is 18km long, 5km wide and 225m deep. Trench B begins at a depth of 3,519m, 732km from the Chixculub impact and is 23km long, 7 km wide and 400m deep. At the end of Trench B is what appears to be a debris deposit 5km long. Their relationship to the Chicxulub impact seems confirmed by their central axis, which when extended intersect at the Chicxulub impact at N Lat 21.33, W Long 89.5. Down range 286km from the end of Trench B is what appears to be the terminal impact of the object that created the two trenches. This is in the form of several large boulders, small seamounts, and islands in shallower depths indicating breakup of the object 1040km from the Chicxulub impact. The trenches are in an area of the Caribbean where currents prevented them from being silted in, preserving their physical form on the ocean floor. The object that created the trenches could have been large ejecta from the impact or possibly part of the asteroid that separated before impact or upon impact and carried on 1000km down range. The trajectory of both trenches is an upward angle of about 3 degrees. This indicates that the trajectory of the object was at a low angle, very high velocity and was deflected slightly upward upon impact with the ocean floor 4,627 below sea level. RESEARCH The first two phases of 10 phases consisting of mapping, exploration, research, and documentation of the impacts have been completed. Phase 1 consisted of assembling available sea floor data of the area of the impacts. Phase 2 consisted of selecting aerial and under water images from Google Earth, preparing bathymetric mapping from a GEBCO_08. BODC raster analysis with 50m contour intervals of the impact area

  14. Snow White Trench Prepared for Sample Collection

    Science.gov (United States)

    2008-01-01

    The informally named 'Snow White' trench is the source for the next sample to be acquired by NASA's Phoenix Mars Lander for analysis by the wet chemistry lab. The Surface Stereo Imager on Phoenix took this shadow-enhanced image of the trench, on the eastern end of Phoenix's work area, on Sol 103, or the 103rd day of the mission, Sept. 8, 2008. The trench is about 23 centimeters (9 inches) wide. The wet chemistry lab is part of Phoenix's Microscopy, Electrochemistry and Conductivity suite of instruments. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  15. Phoenix Deepens Trenches on Mars (3D)

    Science.gov (United States)

    2008-01-01

    The Surface Stereo Imager on NASA's Phoenix Mars Lander took this anaglyph on Oct. 21, 2008, during the 145th Martian day, or sol. Phoenix landed on Mars' northern plains on May 25, 2008. The trench on the upper left, called 'Upper Cupboard,' is about 60 centimeters (24 inches) long and 3 centimeters (1 inch) deep. The trench in the middle,called 'Ice Man,' is about 30 centimeters (12 inches) long and 3 centimeters (1 inch) deep. The trench on the right, called 'La Mancha,' is about 31 centimeters (12 inches) and 5 centimeters (2 inches) deep. The Phoenix mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  16. 300 Area process trench sediment analysis report

    Energy Technology Data Exchange (ETDEWEB)

    Zimmerman, M.G.; Kossik, C.D.

    1987-12-01

    This report describes the results of a sampling program for the sediments underlying the Process Trenches serving the 300 Area on the Hanford reservation. These Process Trenches were the subject of a Closure Plan submitted to the Washington State Department of Ecology and to the US Environmental Protection Agency in lieu of a Part B permit application on November 8, 1985. The closure plan described a proposed sampling plan for the underlying sediments and potential remedial actions to be determined by the sample analyses results. The results and proposed remedial action plan are presented and discussed in this report. 50 refs., 6 figs., 8 tabs.

  17. Phoenix's La Mancha Trench in 3D

    Science.gov (United States)

    2008-01-01

    This anaglyph, taken by NASA's Phoenix Mars Lander's Surface Stereo Imager, was taken on the 131st Martian day, or sol, of the mission (Oct. 7, 2008). The anaglyph highlights the depth of the trench, informally named 'La Mancha,' and reveals the ice layer beneath the soil surface. The trench's depth is about 5 centimeters deep. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  18. Disposal Unit Source Term (DUST) data input guide

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, T.M. [Brookhaven National Lab., Upton, NY (United States)

    1993-05-01

    Performance assessment of a low-level waste (LLW) disposal facility begins with an estimation of the rate at which radionuclides migrate out of the facility (i.e., the source term). The focus of this work is to develop a methodology for calculating the source term. In general, the source term is influenced by the radionuclide inventory, the wasteforms and containers used to dispose of the inventory, and the physical processes that lead to release from the facility (fluid flow, container degradation, wasteform leaching, and radionuclide transport). The computer code DUST (Disposal Unit Source Term) has been developed to model these processes. This document presents the models used to calculate release from a disposal facility, verification of the model, and instructions on the use of the DUST code. In addition to DUST, a preprocessor, DUSTIN, which helps the code user create input decks for DUST and a post-processor, GRAFXT, which takes selected output files and plots them on the computer terminal have been written. Use of these codes is also described.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  20. Ocean Disposal Site Monitoring

    Science.gov (United States)

    EPA is responsible for managing all designated ocean disposal sites. Surveys are conducted to identify appropriate locations for ocean disposal sites and to monitor the impacts of regulated dumping at the disposal sites.

  1. Changes in soil hydraulic properties caused by construction of a simulated waste trench at the Idaho National Engineering Laboratory, Idaho

    Energy Technology Data Exchange (ETDEWEB)

    Shakofsky, S.

    1995-03-01

    In order to assess the effect of filled waste disposal trenches on transport-governing soil properties, comparisons were made between profiles of undisturbed soil and disturbed soil in a simulated waste trench. The changes in soil properties induced by the construction of a simulated waste trench were measured near the Radioactive Waste Management Complex at the Idaho National Engineering Laboratory (INEL) in the semiarid southeast region of Idaho. The soil samples were collected, using a hydraulically-driven sampler to minimize sample disruption, from both a simulated waste trench and an undisturbed area nearby. Results show that the undisturbed profile has distinct layers whose properties differ significantly, whereas the soil profile in the simulated waste trench is, by comparison, homogeneous. Porosity was increased in the disturbed cores, and, correspondingly, saturated hydraulic conductivities were on average three times higher. With higher soil-moisture contents (greater than 0.32), unsaturated hydraulic conductivities for the undisturbed cores were typically greater than those for the disturbed cores. With lower moisture contents, most of the disturbed cores had greater hydraulic conductivities. The observed differences in hydraulic conductivities are interpreted and discussed as changes in the soil pore geometry.

  2. Preparatory Groundwork in 'Snow White' Trench

    Science.gov (United States)

    2008-01-01

    NASA's Phoenix Mars Lander is enlarging a trench informally named 'Snow White' to prepare a cleaned-off area at the top of a subsurface layer of hard material, possibly ice-rich soil. This image taken by Phoenix's Surface Stereo Imager camera on July 13th, the 48th Martian day, or sol, since landing, shows the trench after the previous sol's work by the lander's Robotic Arm. The size of the trench in the image is about 30 centimeters (12 inches) by 20 centimeters (8 inches). A shadow of Phoenix's helical antenna falls across the scene, which is on the northeast side of the lander. The image was taken at 3:32 p.m. local solar time at the Phoenix landing site. The Phoenix team plans to use the arm to extend the trench about 15 centimeters (6 inches) further, working toward the lander, in order to have enough surface area both for testing use of the powered rasp on the back of the scoop and also to use a combination of rasping and scooping to gather a sample of ice-rich material for delivering to the Thermal and Evolved-Gas Analyzer. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  3. 300 Area Process Trenches Closure Plan

    Energy Technology Data Exchange (ETDEWEB)

    Luke, S.N.

    1994-08-15

    Since 1987, Westinghouse Hanford Company has been a major contractor to the US Department of Energy, Richland Operations Office and has served as co-operator of the 300 Area Process Trenches, the waste management unit addressed in this closure plan. For the purposes of the Resource Conservation and Recovery Act, Westinghouse Hanford Company is identified as ``co-operator.`` The 300 Area Process Trenches Closure Plan (Revision 0) consists of a Resource Conservation and Recovery Act Part A Dangerous Waste Permit Application, Form 3 and a Resource Conservation and Recovery Act Closure Plan. An explanation of the Part A Permit Application, Form 3 submitted with this document is provided at the beginning of the Part A Section. The closure plan consists of nine chapters and six appendices. The 300 Area Process Trenches received dangerous waste discharges from research and development laboratories in the 300 Area and from fuels fabrication processes. This waste consisted of state-only toxic (WT02), corrosive (D002), chromium (D007), spent halogenated solvents (F001, F002, and F003), and spent nonhalogented solvent (F005). Accurate records are unavailable concerning the amount of dangerous waste discharged to the trenches. The estimated annual quantity of waste (item IV.B) reflects the total quantity of both regulated and nonregulated waste water that was discharged to the unit.

  4. Color View 'Dodo' and 'Baby Bear' Trenches

    Science.gov (United States)

    2008-01-01

    NASA's Phoenix Mars Lander's Surface Stereo Imager took this image on Sol 14 (June 8, 2008), the 14th Martian day after landing. It shows two trenches dug by Phoenix's Robotic Arm. Soil from the right trench, informally called 'Baby Bear,' was delivered to Phoenix's Thermal and Evolved-Gas Analyzer, or TEGA, on Sol 12 (June 6). The following several sols included repeated attempts to shake the screen over TEGA's oven number 4 to get fine soil particles through the screen and into the oven for analysis. The trench on the left is informally called 'Dodo' and was dug as a test. Each of the trenches is about 9 centimeters (3 inches) wide. This view is presented in approximately true color by combining separate exposures taken through different filters of the Surface Stereo Imager. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  5. Trench capacitor and method for producing the same

    NARCIS (Netherlands)

    Liu, J.; Roest, A.L.; Roozeboom, F.; Shabro, V.

    2013-01-01

    A method of fabricating a trench capacitor, and a trench capacitor fabricated thereby, are disclosed. The method involves the use of a vacuum impregnation process for a sol-gel film, to facilitate effective deposition of high-permittivity materials within a trench in a semiconductor substrate, to pr

  6. Trench capacitor and method for producing the same

    NARCIS (Netherlands)

    Liu, J.; Roest, A.L.; Roozeboom, F.; Shabro, V.

    2013-01-01

    A method of fabricating a trench capacitor, and a trench capacitor fabricated thereby, are disclosed. The method involves the use of a vacuum impregnation process for a sol-gel film, to facilitate effective deposition of high-permittivity materials within a trench in a semiconductor substrate, to

  7. Trenches for building blocks of advanced planar components

    DEFF Research Database (Denmark)

    Haiyan, Ou

    2004-01-01

    Trenches are fundamental structures used to build advanced optical planar waveguide components. In this letter, the fabrication of trenches across silica-on-silicon waveguides using inductively coupled plasma etching is presented. These trenches were etched deep into the silicon substrate...

  8. Launch Pad Flame Trench Refractory Materials

    Science.gov (United States)

    Calle, Luz M.; Hintze, Paul E.; Parlier, Christopher R.; Bucherl, Cori; Sampson, Jeffrey W.; Curran, Jerome P.; Kolody, Mark; Perusich, Steve; Whitten, Mary

    2010-01-01

    The launch complexes at NASA's John F. Kennedy Space Center (KSC) are critical support facilities for the successful launch of space-based vehicles. These facilities include a flame trench that bisects the pad at ground level. This trench includes a flame deflector system that consists of an inverted, V-shaped steel structure covered with a high temperature concrete material five inches thick that extends across the center of the flame trench. One side of the "V11 receives and deflects the flames from the orbiter main engines; the opposite side deflects the flames from the solid rocket boosters. There are also two movable deflectors at the top of the trench to provide additional protection to shuttle hardware from the solid rocket booster flames. These facilities are over 40 years old and are experiencing constant deterioration from launch heat/blast effects and environmental exposure. The refractory material currently used in launch pad flame deflectors has become susceptible to failure, resulting in large sections of the material breaking away from the steel base structure and creating high-speed projectiles during launch. These projectiles jeopardize the safety of the launch complex, crew, and vehicle. Post launch inspections have revealed that the number and frequency of repairs, as well as the area and size of the damage, is increasing with the number of launches. The Space Shuttle Program has accepted the extensive ground processing costs for post launch repair of damaged areas and investigations of future launch related failures for the remainder of the program. There currently are no long term solutions available for Constellation Program ground operations to address the poor performance and subsequent failures of the refractory materials. Over the last three years, significant liberation of refractory material in the flame trench and fire bricks along the adjacent trench walls following Space Shuttle launches have resulted in extensive investigations of

  9. The potential for criticality following disposal of uranium at low-level waste facilities: Uranium blended with soil

    Energy Technology Data Exchange (ETDEWEB)

    Toran, L.E.; Hopper, C.M.; Naney, M.T. [and others

    1997-06-01

    The purpose of this study was to evaluate whether or not fissile uranium in low-level-waste (LLW) facilities can be concentrated by hydrogeochemical processes to permit nuclear criticality. A team of experts in hydrology, geology, geochemistry, soil chemistry, and criticality safety was formed to develop achievable scenarios for hydrogeochemical increases in concentration of special nuclear material (SNM), and to use these scenarios to aid in evaluating the potential for nuclear criticality. The team`s approach was to perform simultaneous hydrogeochemical and nuclear criticality studies to (1) identify some achievable scenarios for uranium migration and concentration increase at LLW disposal facilities, (2) model groundwater transport and subsequent concentration increase via sorption or precipitation of uranium, and (3) evaluate the potential for nuclear criticality resulting from potential increases in uranium concentration over disposal limits. The analysis of SNM was restricted to {sup 235}U in the present scope of work. The outcome of the work indicates that criticality is possible given established regulatory limits on SNM disposal. However, a review based on actual disposal records of an existing site operation indicates that the potential for criticality is not a concern under current burial practices.

  10. Estimation of natural ground water recharge for the performance assessment of a low-level waste disposal facility at the Hanford Site

    Energy Technology Data Exchange (ETDEWEB)

    Rockhold, M.L.; Fayer, M.J.; Kincaid, C.T.; Gee, G.W.

    1995-03-01

    In 1994, the Pacific Northwest Laboratory (PNL) initiated the Recharge Task, under the PNL Vitrification Technology Development (PVTD) project, to assist Westinghouse Hanford Company (WHC) in designing and assessing the performance of a low-level waste (LLW) disposal facility for the US Department of Energy (DOE). The Recharge Task was established to address the issue of ground water recharge in and around the LLW facility and throughout the Hanford Site as it affects the unconfined aquifer under the facility. The objectives of this report are to summarize the current knowledge of natural ground water recharge at the Hanford Site and to outline the work that must be completed in order to provide defensible estimates of recharge for use in the performance assessment of this LLW disposal facility. Recharge studies at the Hanford Site indicate that recharge rates are highly variable, ranging from nearly zero to greater than 100 mm/yr depending on precipitation, vegetative cover, and soil types. Coarse-textured soils without plants yielded the greatest recharge. Finer-textured soils, with or without plants, yielded the least. Lysimeters provided accurate, short-term measurements of recharge as well as water-balance data for the soil-atmosphere interface and root zone. Tracers provided estimates of longer-term average recharge rates in undisturbed settings. Numerical models demonstrated the sensitivity of recharge rates to different processes and forecast recharge rates for different conditions. All of these tools (lysimetry, tracers, and numerical models) are considered vital to the development of defensible estimates of natural ground water recharge rates for the performance assessment of a LLW disposal facility at the Hanford Site.

  11. Simulation of interdigitated back contact solar cell with trench structure

    Science.gov (United States)

    Kim, Soo Min; Chun, Seungju; Kang, Min Gu; Song, Hee-Eun; Lee, Jong-Han; Boo, Hyunpil; Bae, Soohyun; Kang, Yoonmook; Lee, Hae-Seok; Kim, Donghwan

    2015-02-01

    We performed two-dimensional technology computer-aided design simulations for interdigitated back contact (IBC) solar cells with rear trench structures (TS), denoted here as TS-IBC solar cells. First, we calculated a reference simulation model for conventional IBC solar cells. We then assumed a trench structure at the rear surface of the IBC solar cell. For this structure, we analyzed solar cell performance as a function of various trench depths and type. It was found that emitter trench formation affects minority carrier collection, such that the short-circuit current density increases with increasing trench depth. However, the back-surface field (BSF) trench exhibited poor minority carrier collection, which reduced the conversion efficiency of the TS-IBC solar cells. It was also found that for the same trench depth (30 μm), the difference in conversion efficiencies of an IBC solar cell with an emitter trench and that with a BSF trench was 0.6%. We are thus convinced that the emitter trench structure is more important than the BSF trench structure.

  12. Russian low-level waste disposal program

    Energy Technology Data Exchange (ETDEWEB)

    Lehman, L. [L. Lehman and Associates, Inc., Burnsville, MN (United States)

    1993-03-01

    The strategy for disposal of low-level radioactive waste in Russia differs from that employed in the US. In Russia, there are separate authorities and facilities for wastes generated by nuclear power plants, defense wastes, and hospital/small generator/research wastes. The reactor wastes and the defense wastes are generally processed onsite and disposed of either onsite, or nearby. Treating these waste streams utilizes such volume reduction techniques as compaction and incineration. The Russians also employ methods such as bitumenization, cementation, and vitrification for waste treatment before burial. Shallow land trench burial is the most commonly used technique. Hospital and research waste is centrally regulated by the Moscow Council of Deputies. Plans are made in cooperation with the Ministry of Atomic Energy. Currently the former Soviet Union has a network of low-level disposal sites located near large cities. Fifteen disposal sites are located in the Federal Republic of Russia, six are in the Ukraine, and one is located in each of the remaining 13 republics. Like the US, each republic is in charge of management of the facilities within their borders. The sites are all similarly designed, being modeled after the RADON site near Moscow.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  14. Benchmarking Exercises To Validate The Updated ELLWF GoldSim Slit Trench Model

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, G. A.; Hiergesell, R. A.

    2013-11-12

    The Savannah River National Laboratory (SRNL) results of the 2008 Performance Assessment (PA) (WSRC, 2008) sensitivity/uncertainty analyses conducted for the trenches located in the EArea LowLevel Waste Facility (ELLWF) were subject to review by the United States Department of Energy (U.S. DOE) Low-Level Waste Disposal Facility Federal Review Group (LFRG) (LFRG, 2008). LFRG comments were generally approving of the use of probabilistic modeling in GoldSim to support the quantitative sensitivity analysis. A recommendation was made, however, that the probabilistic models be revised and updated to bolster their defensibility. SRS committed to addressing those comments and, in response, contracted with Neptune and Company to rewrite the three GoldSim models. The initial portion of this work, development of Slit Trench (ST), Engineered Trench (ET) and Components-in-Grout (CIG) trench GoldSim models, has been completed. The work described in this report utilizes these revised models to test and evaluate the results against the 2008 PORFLOW model results. This was accomplished by first performing a rigorous code-to-code comparison of the PORFLOW and GoldSim codes and then performing a deterministic comparison of the two-dimensional (2D) unsaturated zone and three-dimensional (3D) saturated zone PORFLOW Slit Trench models against results from the one-dimensional (1D) GoldSim Slit Trench model. The results of the code-to-code comparison indicate that when the mechanisms of radioactive decay, partitioning of contaminants between solid and fluid, implementation of specific boundary conditions and the imposition of solubility controls were all tested using identical flow fields, that GoldSim and PORFLOW produce nearly identical results. It is also noted that GoldSim has an advantage over PORFLOW in that it simulates all radionuclides simultaneously - thus avoiding a potential problem as demonstrated in the Case Study (see Section 2.6). Hence, it was concluded that the follow

  15. Conductivity Probe after Trench-Bottom Placement

    Science.gov (United States)

    2008-01-01

    Needles of the thermal and conductivity probe on NASA's Phoenix Mars Lander were positioned into the bottom of a trench called 'Upper Cupboard' during Sol 86 (Aug. 21, 2008), or 86th Martian day after landing. This image of the conductivity probe after it was raised back out of the trench was taken by Phoenix's Robotic Arm Camera. The conductivity probe is at the wrist of the robotic arm's scoop. The probe measures how fast heat and electricity move from one needle to an adjacent one through the soil or air between the needles. Conductivity readings can be indicators about water vapor, water ice and liquid water. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  16. 'Snow White' Trench After Scraping (Stereo View)

    Science.gov (United States)

    2008-01-01

    This 3D view from the Surface Stereo Imager on NASA's Phoenix Mars Lander shows the trench informally named 'Snow White.' This anaglyph was taken after a series of scrapings by the lander's Robotic Arm on the 58th Martian day, or sol, of the mission (July 23, 2008). The scrapings were done in preparation for collecting a sample for analysis from a hard subsurface layer where soil may contain frozen water. The trench is 4 to 5 centimeters (about 2 inches) deep, about 23 centimeters (9 inches) wide and about 60 centimeters (24 inches) long. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  17. Storm-water management through Infiltration trenches

    OpenAIRE

    Chahar, Bhagu Ram; Graillot, Didier; Gaur, Shishir

    2012-01-01

    International audience; With urbanization, the permeable soil surface area through which recharge by infiltration can occur is reducing. This is resulting in much less ground-water recharge and greatly increased surface run-off. Infiltration devices, which redirect run-off waters from the surface to the sub-surface environments, are commonly adopted to mitigate the negative hydrologic effects associated with urbanization. An infiltration trench alone or in combination with other storm water m...

  18. Stresses in silicon substrates near isolation trenches

    Science.gov (United States)

    Chidambarrao, D.; Peng, J. P.; Srinivasan, G. R.

    1991-11-01

    We describe a methodology for obtaining stresses near isolation trenches in silicon considering the entire trench forming process. A two-dimensional plane strain finite element stress analysis is performed for a trench with a thermal SiO2 sidewall and polysilicon ``fill'' which includes the cumulative stresses from the superposition of (i) residual stresses from the thermal oxidation step, (ii) the intrinsic stress from the polysilicon deposition, and (iii) stresses due to the coefficient of thermal expansion mismatch between SiO2 and silicon during the temperature cycles involved in the process. The thermal oxidation step is simulated using a two-dimensional nonlinear viscoelastic program novel [in Proceedings of the Second International Symposium on Process Physics and Modeling in Semiconductor Technology, edited by G. R. Srinivasan, J. D. Plummer, and S. T. Pantelides (Electrochemical Society, Pennington, NJ, 1991), p. 772], that produces the oxide shape and stress at the oxide-silicon interface which is converted into equivalent nodal forces on the finite element grid. We have also made a three-dimensional finite element analysis of the thermal mismatch stresses between a parallelopipedic oxide inclusion in silicon with anisotropic properties and have compared these results with the analytical results [J. Appl. Phys. 66, 2741 (1989); 67, 1092 (1990)] in which the oxide and silicon are assumed to have identical isotropic elastic properties.

  19. Greater Confinement Disposal Test at the Nevada Test Site, Final Technology Report

    Energy Technology Data Exchange (ETDEWEB)

    Dickman, P. T.

    1989-01-01

    The Greater Confinement Disposal Test (GCDT) was conducted at the Nevada Test Site to demonstrate an alternative method for management of high-specific-activity (HSA) low-level waste (LLW). The GCDT was initially conceived as a method for managing small volumes of highly concentrated tritium wastes, which, due to their environmental mobiilty, are considered unsuitable for routine shallow land disposal. Later, the scope of the GCDT was increased to address a variety of other "problem" HSA wastes including isotope sources and thermal generating wastes. The basic design for the GCDT evolved from a series of studies and assessments. Operational design objectives were to (1) emplace the wastes at a depth sufficient to minimize or eliminate routine environmental transport mechanisms and instrusion scenarios and (2) provide sufficient protection for operations personnel in the handling of HSA sources. To achieve both objectives, a large diameter borehole was selected. The GCDT consisted of a borehole 3 meters (10 feet) in diameter and 36 meters (120 feet) deep, surrounded by nine monitoring holes at varying radii. The GCDT was instrumented for the measurement of temperature, moisture, and soil-gas content. Over one million curies of HSA LLW were emplaced in GCDT. This report reviews the development of the GCDT project and presents analyses of data collected.

  20. Caustic Recycling Pilot Unit to Separate Sodium from LLW at Hanford Site - 12279

    Energy Technology Data Exchange (ETDEWEB)

    Pendleton, Justin; Bhavaraju, Sai; Priday, George; Desai, Aditya; Duffey, Kean; Balagopal, Shekar [Ceramatec Inc., Salt Lake City, UT 84119 (United States)

    2012-07-01

    As part of the Department of Energy (DOE) sponsored Advanced Remediation Technologies initiative, a scheme was developed to combine Continuous Sludge Leaching (CSL), Near-Tank Cesium Removal (NTCR), and Caustic Recycling Unit (CRU) using Ceramatec technology, into a single system known as the Pilot Near-Tank Treatment System (PNTTS). The Cesium (Cs) decontaminated effluent from the NTCR process will be sent to the caustic recycle process for recovery of the caustic which will be reused in another cycle of caustic leaching in the CSL process. Such an integrated mobile technology demonstration will give DOE the option to insert this process for sodium management at various sites in Hanford, and will minimize the addition of further sodium into the waste tanks. This allows for recycling of the caustic used to remove aluminum during sludge washing as a pretreatment step in the vitrification of radioactive waste which will decrease the Low Level Waste (LLW) volume by as much as 39%. The CRU pilot process was designed to recycle sodium in the form of pure sodium hydroxide. The basis for the design of the 1/4 scale pilot caustic recycling unit was to demonstrate the efficient operation of a larger scale system to recycle caustic from the NTCR effluent stream from the Parsons process. The CRU was designed to process 0.28 liter/minute of NTCR effluent, and generate 10 M concentration of 'usable' sodium hydroxide. The proposed process operates at 40 deg. C to provide additional aluminum solubility and then recover the sodium hydroxide to the point where the aluminum is saturated at 40 deg. C. A system was developed to safely separate and vent the gases generated during operation of the CRU with the production of 10 M sodium hydroxide. Caustic was produced at a rate between 1.9 to 9.3 kg/hr. The CRU was located inside an ISO container to allow for moving of the unit close to tank locations to process the LLW stream. Actual tests were conducted with the NTCR effluent

  1. Issues and Recommendations Arising from the Idaho National Laboratory Remote-Handled Low-Level Waste Disposal Facility Composite Analysis - 13374

    Energy Technology Data Exchange (ETDEWEB)

    Rood, Arthur S.; Schafer, Annette L.; Sondrup, A. Jeff [Idaho National Laboratory, Battelle Energy Alliance, P.O. Box 1625, Idaho Falls, ID 83401-2107 (United States)

    2013-07-01

    Development of the composite analysis (CA) for the Idaho National Laboratory's (INLs) proposed remote-handled (RH) low-level waste (LLW) disposal facility has underscored the importance of consistency between analyses conducted for site-specific performance assessments (PAs) for LLW disposal facilities, sites regulated by the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) [1], and residual decontamination and decommissioning (D and D) inventories. Consistency is difficult to achieve because: 1) different legacy sources and compliance time-periods were deemed important for each of the sites evaluated at INL (e.g., 100 years for CERCLA regulated facilities vs. 1,000 years for LLW disposal facilities regulated under U.S. Department of Energy (DOE) Order 435.1 [2]); 2) fate and transport assumptions, parameters, and models have evolved through time at the INL including the use of screening-level parameters vs. site-specific values; and 3) evaluation objectives for the various CERCLA sites were inconsistent with those relevant to either the PA or CA including the assessment of risk rather than effective dose. The proposed single site-wide CA approach would provide needed consistency, allowing ready incorporation of new information and/or facilities in addition to being cost effective in terms of preparation of CAs and review by the DOE. A single site-wide CA would include a central database of all existing INL sources, including those from currently operating LLW facilities, D and D activities, and those from the sites evaluated under CERCLA. The framework presented for the INL RH-LLW disposal facility allows for development of a single CA encompassing air and groundwater impacts. For groundwater impacts, a site-wide MODFLOW/MT3D-MS model was used to develop unit-response functions for all potential sources providing responses for a grid of receptors. Convolution and superposition of the response functions are used to compute

  2. Interpretation of vadose zone monitoring system data near engineered trench 1

    Energy Technology Data Exchange (ETDEWEB)

    Flach, G. P. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Whiteside, T. S. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-12-12

    The E-Area Vadose Zone Monitoring System (VZMS) includes lysimeter sampling points at many locations alongside and angling beneath the Engineered Trench #1 (ET1) disposal unit footprint. The sampling points for ET1 were selected for this study because collectively they showed consistently higher tritium (H-3) concentrations than lysimeters associated with other trench units. The VZMS tritium dataset for ET1 from 2001 through 2015 comprises concentrations at or near background levels at approximately half of locations through time, concentrations up to about 600 pCi/mL at a few locations, and concentrations at two locations that have exceeded 1000 pCi/mL. The highest three values through 2015 were 6472 pCi/mL in 2014 and 4533 pCi/mL in 2013 at location VL-17, and 3152 pCi/mL in 2007 at location VL-15. As a point of reference, the drinking water standard for tritium and a DOE Order 435.1 performance objective in the saturated zone at the distant 100-meter facility perimeter is 20 pCi/mL. The purpose of this study is to assess whether these elevated concentrations are indicative of a general trend that could challenge 2008 E-Area Performance Assessment (PA) conclusions, or are isolated perturbations that when considered in the context of an entire disposal unit would support PA conclusions.

  3. THE BC CRIBS & TRENCHES GEOPHYSICAL CHARACTERIZATION PROJECT ONE STEP FORWARD IN HANFORDS CLEANUP PROCESS

    Energy Technology Data Exchange (ETDEWEB)

    BENECKE, MN.W.

    2006-02-22

    A geophysical characterization project was conducted at the BC Cribs and Trenches Area, located south of 200 East at the Hanford Site. The area consists of 26 waste disposal trenches and cribs, which received approximately 30 million gallons of liquid waste from the uranium recovery process and the ferrocyanide processes associated with wastes generated by reprocessing nuclear fuel. Waste discharges to BC Cribs contributed perhaps the largest liquid fraction of contaminants to the ground in the 200 Areas. The site also includes possibly the largest inventory of Tc-99 ever disposed to the soil at Hanford with an estimated quantity of 400 Ci. Other waste constituents included high volumes of nitrate and U-238. The geophysical characterization at the 50 acre site primarily included high resolution resistivity (HRR). The resistivity technique is a non-invasive method by which electrical resistivity data are collected along linear transects, and data are presented as continuous profiles of subsurface electrical properties. The transects ranged in size from about 400-700 meters and provided information down to depths of 60 meters. The site was characterized by a network of 51 HRR lines with a total of approximately 19.7 line kilometers of data collected parallel and perpendicular to the trenches and cribs. The data were compiled to form a three-dimensional representation of low resistivity values. Low resistivity, or high conductivity, is indicative of high ionic strength soil and porewater resulting from the migration of nitrate and other inorganic constituents through the vadose zone. High spatial density soil data from a single borehole, that included coincident nitrate concentrations, electrical conductivity, and Tc-99, were used to transform the electrical resistivity data into a nitrate plume. The plume was shown to extend laterally beyond the original boundaries of the waste site and, in one area, to depths that exceeded the characterization strategy. It is

  4. Topical Report ''Corrosion Evaluation of LLW2 Skid-B Weld Failure Mechanisms (44139-92)

    Energy Technology Data Exchange (ETDEWEB)

    JI Young Chang

    2001-05-31

    An independent investigation of pipe welding leaks from the Low-Level Waste 2 (LLW2) Skid-B System for the possibilities of improper welding (IW), microbiologically influenced corrosion (MIC), sensitization, chloride pitting corrosion (CPC), and intergranular stress corrosion cracking (IGSCC) was conducted. The results show the prevailing mechanisms that caused the leaks are identified as IW, CPC, and the improper selection of weld filler material for the base metals in an environment of the North Plateau underground water. These is no evidence of MIC, sensitization, or IGSCC. The chloride pitting corrosion mechanism that took place at all the welds are also described. All the pipelines were replaced with polyvinyl chloride (PVC) for cost saving and the LLW2 Skid B System has been successfully operating since 1999. This report summarizes the findings and recommendations associated with preventive measures for future operations. The LLW2 Facility is a replacement for an existing waste treatment system. The Facility processes two different waste streams through two different ''skids.'' After seven months of operation, one of the two skids began to leak. Extensive evaluation of the corrosion mechanisms and the contributing factors are documented in this report. This report principally evaluates the physical and chemical configurations that led to the corrosion and leaks. Chloride pitting corrosion, exacerbated by weld defects, is the corrosion mechanism. The report also discusses fabrication and Quality Assurance (QA)/Quality Control (QC) actions that would have prevented their occurrence. It is believed that in the absence of either the defects or the chloride concentrations, corrosion would not have occurred. In developing the specification for processing skids to be used in the Facility, high chloride was not identified as a parameter of concern. As such, piping fabrication and inspection standards for the system did not identify more rigorous

  5. Radiological performance assessment for the Z-Area Saltstone Disposal Facility

    Energy Technology Data Exchange (ETDEWEB)

    Cook, J.R.; Fowler, J.R. [Westinghouse Savannah River Co., Aiken, SC (United States)

    1992-12-18

    This radiological performance assessment (RPA) for the Savannah River Site (SRS) Saltstone Disposal Facility (SDF) was prepared in accordance with the requirements of Chapter III of the US Department of Energy Order 5820.2A. The Order specifies that an RPA should provide reasonable assurance that a low-level waste (LLW) disposal facility will comply with the performance objectives of the Order. The performance objectives require that: (1) exposures of the general public to radioactivity in the waste or released from the waste will not result in an effective dose equivalent of 25 mrem per year; (2) releases to the atmosphere will meet the requirements of 40 CFR 61; (3) inadvertent intruders will not be committed to an excess of an effective dose equivalent of 100 mrem per year from chronic exposure, or 500 mrem from a single acute exposure; and (4) groundwater resources will be protected in accordance with Federal, State and local requirements.

  6. Treated Effluent Disposal Facility

    Data.gov (United States)

    Federal Laboratory Consortium — Treated non-hazardous and non-radioactive liquid wastes are collected and then disposed of through the systems at the Treated Effluent Disposal Facility (TEDF). More...

  7. Special Analysis: 2017-001 Disposal of Drums Containing Enriched Uranium in Pit 38 at Technical Area 54, Area G

    Energy Technology Data Exchange (ETDEWEB)

    Birdsell, Kay Hanson [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Stauffer, Philip H. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); French, Sean B. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-06-05

    Los Alamos National Laboratory (LANL) generates radioactive waste as a result of various activities. Operational waste is generated from a wide variety of research and development activities including nuclear weapons development, energy production, and medical research. Environmental restoration (ER), and decontamination and decommissioning (D&D) waste is generated as contaminated sites and facilities at LANL undergo cleanup or remediation. The majority of this waste is low-level radioactive waste (LLW) and is disposed of at the Technical Area 54 (TA-54), Area G disposal facility. This special analysis, SA 2017-001, evaluates the potential impacts of disposing of this waste in Pit 38 at Area G based on the assumptions that form the basis of the Area G PA/CA. Section 2 describes the methods used to conduct the analysis; the results of the evaluation are provided in Section 3; and conclusions and recommendations are provided in Section 4.

  8. Diging simulation of a narrow trench

    Science.gov (United States)

    Anghelache, D. G.; Goanta, A. M.

    2016-08-01

    In this paper, we realized digging process simulation for a narrow trench using special equipment located at a mini excavator. These types of machines digging perform the longitudinal direction to the direction of travel, making trenches with widths of 0.4 m and depths of 3.5 -7.0 m. These are necessary for the location of underground cables or draining water in agriculture. For Parametric modelling of parts included in ensemble has used software from Siemens NX 7.5, we produce sketches of each piece, using following commands: Sketch, Profile (Line), Arc, Circle, Quick Trim Quick Extend, Constraints. Depending on the layout of each piece can also use other commands such as: Chamfer, Rotate, Mirror Curve, Offset Curve, etc. After completion of sketch and dimensioning commands was: Extrude, Revolve, and at this stage the play may various modifications such as drilling, removal of certain volumes of piece showing various forms or change the appearance of surfaces (thread cutting, bevelling). This paper was realized with this parametric modelling software because presents major advantages including: control over the design, making design speed and increasing productivity; increasing product quality, reducing design risk recovery and time work, less human effort and reduced financial resources throughout the process.

  9. Performance assessment for the class L-II disposal facility

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    This draft radiological performance assessment (PA) for the proposed Class L-II Disposal Facility (CIIDF) on the Oak Ridge Reservation (ORR) has been prepared to demonstrate compliance with the requirements of the US Department of Energy Order 5820.2A. This PA considers the disposal of low-level radioactive wastes (LLW) over the operating life of the facility and the long-term performance of the facility in providing protection to public health and the environment. The performance objectives contained in the order require that the facility be managed to accomplish the following: (1) Protect public health and safety in accordance with standards specified in environmental health orders and other DOE orders. (2) Ensure that external exposure to the waste and concentrations of radioactive material that may be released into surface water, groundwater, soil, plants, and animals results in an effective dose equivalent (EDE) that does not exceed 25 mrem/year to a member of the public. Releases to the atmosphere shall meet the requirements of 40 CFR Pt. 61. Reasonable effort should be made to maintain releases of radioactivity in effluents to the general environment as low as reasonably achievable. (1) Ensure that the committed EDEs received by individual who inadvertently may intrude into the facility after the loss of active institutional control (100 years) will not exceed 100 mrem/year for continuous exposure of 500 mrem for a single acute exposure. (4) Protect groundwater resources, consistent with federal, state, and local requirements.

  10. Annual Status Report (FY2016) Performance Assessment for the Environmental Restoration Disposal Facility

    Energy Technology Data Exchange (ETDEWEB)

    Casbon, M. A. [CH2M HILL Plateau Remediation Company, Richland, WA (United States); Nichols, W. E. [CH2M HILL Plateau Remediation Company, Richland, WA (United States)

    2017-03-15

    DOE O 435.1, Radioactive Waste Management, and DOE M 435.1-1, Radioactive Waste Management Manual, require that a determination of continued adequacy of the performance assessment (PA), composite analysis (CA), and disposal authorization statement (DAS) be made on an annual basis, and it must consider the results of data collection and analysis from research, field studies, and monitoring. Annual summaries of low-level waste (LLW) disposal operations must be prepared with respect to the conclusions and recommendations of the PA and CA, and a determination of the need to revise the PA or CA must be made. The annual summary requirement provides a structured approach for demonstrating the continued adequacy of the PA and CA in demonstrating a reasonable expectation that the performance objectives will be met. This annual summary addresses only the status of the Environmental Restoration Disposal Facility (ERDF) PA (CP-60089, Performance Assessment for the Environmental Restoration Disposal Facility, Hanford Site, Washington, formerly WCH-520 Rev. 1)1. The CA for ERDF is supported by DOE/RL-2016-62, Annual Status Report (FY 2016): Composite Analysis of Low Level Waste Disposal in the Central Plateau at the Hanford Site. The ERDF PA portion of the CA document is found in Section 3.1.4, and the ERDF operations portion is found in Section 3.3.3.2 of that document.

  11. Scattering and extinction from high-aspect-ratio trenches

    DEFF Research Database (Denmark)

    Roberts, Alexander Sylvester; Søndergaard, Thomas; Chirumamilla, Manohar;

    2015-01-01

    We construct a semi-analytical model describing the scattering, extinction and absorption properties of a high aspect-ratio trench in a metallic film. We find that these trenches act as highly efficient scatterers of free waves. In the perfect conductor limit, which for many metals is approached...

  12. Development of High-Voltage Trench IGBT%高压Trench IGBT的研制

    Institute of Scientific and Technical Information of China (English)

    唐红祥; 计建新; 孙向东; 孙永生; 曹亮

    2012-01-01

    介绍了当前绝缘栅双极晶体管(IGBT)的几种结构及沟槽型IGBT的发展现况,分析了高电压沟槽型非穿通(NPT) IGBT的结构及工艺特点.通过理论分析计算出初步器件的相关参数,再利用ISE仿真软件模拟器件的结构及击穿和导通特性,结合现有沟槽型DMOS工艺流程,确定了器件采用多分压环加多晶场板的复合终端、条状元胞、6μm深度左右沟槽、低浓度背面掺杂分布与小于180 μm厚度的器件结构,可以很好地平衡击穿特性与导通特性对器件结构的要求.成功研制出1 200 V沟槽型NPT系列产品,并通过可靠性考核,经过电磁炉应用电路实验,结果表明IGBT器件可稳定工作,满足应用要求.该设计可适合国内半导体生产线商业化生产.%The structures of isulated gate bipolar transistor (IGBT) and current status of the trench IGBT devices development were introduced. Then the structure and process features of high-voltage trench non-punch-through ( NPT) IGBT devices were analyzed. After the dimension was computed, the device structure, breaking and conducting characteristics were simulated by ISE software, Combining with the trench DMOS process flow, the devices adopted field rings and poly field plate, strips of cell, 6 μm depth of trench, low concentration doped back side and less than 180 μm thickness. The requirement between blocking and conducting characteristics can be satisfied well. A series of 1 200 V NPT trench IGBT expanded successfully by Huajing, reliability test passed, and IGBT device worked well on induction cooker ( IH ). The trench IGBT can be produced commercially for domestic semiconductor production lines.

  13. The Relationships of Upper Plate Ridge-Trench-Trench and Ridge-Trench-Transform Triple Junction Evolution to Arc Lengthening, Subduction Zone initiation and Ophiolitic Forearc Obduction

    Science.gov (United States)

    Casey, J.; Dewey, J. F.

    2013-12-01

    The principal enigma of large obducted ophiolite slabs is that they clearly must have been generated by some form of organized sea-floor spreading/plate-accretion, such as may be envisioned for the oceanic ridges, yet the volcanics commonly have arc affinity (Miyashiro) with boninites (high-temperature/low-pressure, high Mg and Si andesites), which are suggestive of a forearc origin. PT conditions under which boninites and metamorphic soles form and observations of modern forearc systems lead us to the conclusion that ophiolite formation is associated with overriding plate spreading centers that intersect the trench to form ridge-trench-trench of ridge-trench-tranform triple junctions. The spreading centers extend and lengthen the forearc parallel to the trench and by definition are in supra-subduction zone (SSZ) settings. Many ophiolites likewise have complexly-deformed associated mafic-ultramafic assemblages that suggest fracture zone/transform along their frontal edges, which in turn has led to models involving the nucleation of subduction zones on fracture zones or transpressional transforms. Hitherto, arc-related sea-floor-spreading has been considered to be either pre-arc (fore-arc boninites) or post-arc (classic Karig-style back arc basins that trench-parallel split arcs). Syn-arc boninites and forearc oceanic spreading centers that involve a stable ridge/trench/trench triple or a ridge-trench-transform triple junction, the ridge being between the two upper plates, are consistent with large slab ophiolite formation in an obduction-ready settting. The direction of subduction must be oblique with a different sense in the two subduction zones and the oblique subduction cannot be partitioned into trench orthogonal and parallel strike-slip components. As the ridge spreads, new oceanic lithosphere is created within the forearc, the arc and fore-arc lengthen significantly, and a syn-arc ophiolite forearc complex is generated by this mechanism. The ophiolite ages

  14. The hydrological impact of contour trenching in Vietnam

    Science.gov (United States)

    Pramana, K. E. R.; Ertsen, M. W.; Uhlenbrook, S.; de Laat, P.; Nonner, J.

    2009-04-01

    At the foothill in the driest rural area in Vietnam, at Ninh Thuan province, poor farmers cultivate up-land crops during the wet season. The area is about 9 hectares of deforested land with a slope up to 8% and has a geology surface of crusted sands and gravels. Water is scarce during the dry season and runs off rapidly during the wet season. Hence, to provide sustainable water resources and support crop growth, a project started in 2007 aiming introducing contour trenching. The main purpose of contour trenching is to trap run off, increase soil moisture for vegetation growth and recharge the groundwater. In order to investigate the impact of the trenches, a field monitoring program was initiated measuring rainfall, soil moisture content, surface water levels and groundwater levels. Recorded annual rainfall reached 600 mm. The groundwater levels are relatively deep and constant at -8 and -10 meters. The soil moisture content ranged from 3% at the driest condition to 37% below the trench at ponding. Water levels in trenches differed from uphill to downhill with higher levels at the first trench uphill. After ponding, water in the trenches infiltrates within a period of days. In this contribution, available field measurements are analyzed in two ways. First, runoff is analyzed. Immediately after significant rainfall events, the observed ponding levels in the trenches with defined uphill runoff areas can be related to the rainfall. The results show reduction of runoff coefficients per trench in downhill direction. Second, the two dimension numerical saturated-unsaturated model Hydrus 2-D was used to simulate the soil moisture content measurements. Model results confirm that infiltration is a quick process in this area with its loamy sand soils. Based on these analyzes, potential of contour trenches for local water retention and groundwater recharge will be discussed.

  15. Frost seen on Snow White Trench

    Science.gov (United States)

    2008-01-01

    The Surface Stereo Imager (SSI) on NASA's Phoenix Mars Lander took this shadow-enhanced false color image of the 'Snow White' trench, on the eastern end of Phoenix's digging area. The image was taken on Sol 144, or the 144th day of the mission, Oct. 20, 2008. Temperatures measured on Sol 151, the last day weather data were received, showed overnight lows of minus128 Fahrenheit (minus 89 Celsius) and day time highs in the minus 50 F (minus 46 C) range. The last communication from the spacecraft came on Nov. 2, 2008. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  16. Animation of 'Dodo' and 'Goldilocks' Trenches

    Science.gov (United States)

    2008-01-01

    [figure removed for brevity, see original site] Click on image for animation A pan and zoom animation of the informally named 'Dodo' (on left) and 'Goldilocks' (on right) trenches as seen by the Surface Stereo Imager (SSI) aboard NASA's Phoenix Mars Lander. This animation was based on conditions on the Martian surface on Sol 17 (June 11, 2008), the 17th Martian day of the mission. 'Baby Bear' is the name of the sample taken from 'Goldilocks' and delivered to the Thermal and Evolved-Gas Analyzer (TEGA) instrument. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  17. Oceanic mantle alteration in the trench-outer rise region of the Japan trench

    Science.gov (United States)

    Fujie, G.; Takahashi, T.; Kodaira, S.; Obana, K.; Yamada, T.

    2014-12-01

    Dehydration processes and the expulsion of the water from the subducting oceanic plate affect various subduction-zone processes, including arc volcanism and generation of earthquakes and tremor. Since the amount of chemically bound water in the oceanic plate is highest in serpentinized mantle, it is important to reveal the degree of oceanic mantle serpentinization prior to subduction.In 2009 and 2013, to reveal the structural evolution of the incoming oceanic plate prior to subduction, we conducted wide-angle seismic structural surveys in the trench-outer rise region of the Japan trench. We found P-wave velocity (Vp) within the oceanic crust and mantle gradually decreases toward the trench axis, especially beneath the well-developed horst and grabens. Generally, reduction of Vp suggests two possibilities; one is a fracturing (dry mechanism) and the other is fracturing and water penetration (wet mechanism). The Vp/Vs ratio is a key to distinguish these two possibilities. Using P-to-S converted phases, we successfully modeled Vs within the oceanic crust by the travel-time inversion, and we found the Vp/Vs ratio within the oceanic crust gradually increases toward the trench, suggesting the water infiltration into the oceanic crust. However, it is not straightforward to determine Vs within the oceanic mantle because signal-to-noise ratio of S-wave mantle refraction was too poor to pick arrival times. Therefore, we calculated S-wave mantle refractions by assuming wide variety of Vp/Vs ratio within the oceanic mantle and compared with the observed horizontal data. Although S-wave mantle refraction was observed at only limited number of OBSs, we found that Vp/Vs ratio within the oceanic mantle did not change even in the area where mantle Vp become lower. This implies that the mantle Vp reduction in our seismic profile is mainly governed by the "dry mechanism" or mantle hydration might be confined in only topmost mantle.

  18. Evaluation of Low-Level Waste Disposal Receipt Data for Los Alamos National Laboratory Technical Area 54, Area G Disposal Facility - Fiscal Year 2011

    Energy Technology Data Exchange (ETDEWEB)

    French, Sean B. [Los Alamos National Laboratory; Shuman, Robert [WPS: WASTE PROJECTS AND SERVICES

    2012-04-17

    The Los Alamos National Laboratory (LANL or the Laboratory) generates radioactive waste as a result of various activities. Operational or institutional waste is generated from a wide variety of research and development activities including nuclear weapons development, energy production, and medical research. Environmental restoration (ER), and decontamination and decommissioning (D and D) waste is generated as contaminated sites and facilities at LANL undergo cleanup or remediation. The majority of this waste is low-level radioactive waste (LLW) and is disposed of at the Technical Area 54 (TA-54), Area G disposal facility. U.S. Department of Energy (DOE) Order 435.1 (DOE, 2001) requires that radioactive waste be managed in a manner that protects public health and safety, and the environment. To comply with this order, DOE field sites must prepare and maintain site-specific radiological performance assessments for LLW disposal facilities that accept waste after September 26, 1988. Furthermore, sites are required to conduct composite analyses that account for the cumulative impacts of all waste that has been (or will be) disposed of at the facilities and other sources of radioactive material that may interact with the facilities. Revision 4 of the Area G performance assessment and composite analysis was issued in 2008 (LANL, 2008). These analyses estimate rates of radionuclide release from the waste disposed of at the facility, simulate the movement of radionuclides through the environment, and project potential radiation doses to humans for several on-site and off-site exposure scenarios. The assessments are based on existing site and disposal facility data and on assumptions about future rates and methods of waste disposal. The accuracy of the performance assessment and composite analysis depends upon the validity of the data used and assumptions made in conducting the analyses. If changes in these data and assumptions are significant, they may invalidate or call

  19. 3-D visualisation of palaeoseismic trench stratigraphy and trench logging using terrestrial remote sensing and GPR - a multiparametric interpretation

    Science.gov (United States)

    Schneiderwind, Sascha; Mason, Jack; Wiatr, Thomas; Papanikolaou, Ioannis; Reicherter, Klaus

    2016-03-01

    Two normal faults on the island of Crete and mainland Greece were studied to test an innovative workflow with the goal of obtaining a more objective palaeoseismic trench log, and a 3-D view of the sedimentary architecture within the trench walls. Sedimentary feature geometries in palaeoseismic trenches are related to palaeoearthquake magnitudes which are used in seismic hazard assessments. If the geometry of these sedimentary features can be more representatively measured, seismic hazard assessments can be improved. In this study more representative measurements of sedimentary features are achieved by combining classical palaeoseismic trenching techniques with multispectral approaches. A conventional trench log was firstly compared to results of ISO (iterative self-organising) cluster analysis of a true colour photomosaic representing the spectrum of visible light. Photomosaic acquisition disadvantages (e.g. illumination) were addressed by complementing the data set with active near-infrared backscatter signal image from t-LiDAR measurements. The multispectral analysis shows that distinct layers can be identified and it compares well with the conventional trench log. According to this, a distinction of adjacent stratigraphic units was enabled by their particular multispectral composition signature. Based on the trench log, a 3-D interpretation of attached 2-D ground-penetrating radar (GPR) profiles collected on the vertical trench wall was then possible. This is highly beneficial for measuring representative layer thicknesses, displacements, and geometries at depth within the trench wall. Thus, misinterpretation due to cutting effects is minimised. This manuscript combines multiparametric approaches and shows (i) how a 3-D visualisation of palaeoseismic trench stratigraphy and logging can be accomplished by combining t-LiDAR and GPR techniques, and (ii) how a multispectral digital analysis can offer additional advantages to interpret palaeoseismic and stratigraphic

  20. T-Rex system for operation in TRU, LLW, and hazardous zones. Transuranic storage area-retrieval enclosure program

    Energy Technology Data Exchange (ETDEWEB)

    Kline, H.M. [EG and G Idaho, Inc., Idaho Falls, ID (United States); Andreychek, T.P.; Beeson, B.K. [Martin Marietta Corp., Baltimore, MD (United States). Aero and Naval Systems

    1993-04-01

    There are a large number of sites around the world containing TRU (transuranic) waste, low level waste (LLW), and hazardous areas that require teleoperated, heavy lift manipulators with long reach and high precision to handle the materials stored there. Teleoperation of the equipment is required to reduce the risk to operating personnel to as-low-as-reasonably-achievable (ALARA) levels. The Transuranic Storage Area Remote Excavator system (T-Rex) is designed to fill this requirement at low cost through the integration of a production front shovel excavator with a control system, local and remote operator control stations, a closed-circuit television system (CCTV), multiple end effectors and a quick-change system. This paper describes the conversion of an off-the-shelf excavator with a hydraulic control system, the integration of an onboard remote control system, vision system, and the design of a remote control station.

  1. Sustainable sanitary landfills for neglected small cities in developing countries: The semi-mechanized trench method from Villanueva, Honduras

    Energy Technology Data Exchange (ETDEWEB)

    Oakley, Stewart M., E-mail: soakley@csuchico.edu [Department of Civil Engineering, Chico State University, California State University, Chico, CA 95929 (United States); Jimenez, Ramon, E-mail: rjimenez1958@yahoo.com [Public Works, Municipality of Villanueva, Cortes (Honduras)

    2012-12-15

    Highlights: Black-Right-Pointing-Pointer Open dumping is the most common form of waste disposal in neglected small cities. Black-Right-Pointing-Pointer Semi-mechanized landfills can be a sustainable option for small cities. Black-Right-Pointing-Pointer We present the theory of design and operation of semi-mechanized landfills. Black-Right-Pointing-Pointer Villanueva, Honduras has operated its semi-mechanized landfill for 15 years. Black-Right-Pointing-Pointer The cost of operation is US$4.60/ton with a land requirement of 0.2m{sup 2}/person-year. - Abstract: Open dumping is the most common practice for the disposal of urban solid wastes in the least developed regions of Africa, Asia and Latin America. Sanitary landfill design and operation has traditionally focused on large cities, but cities with fewer than 50,000 in population can comprise from 6% to 45% of a given country's total population. These thousands of small cities cannot afford to operate a sanitary landfill in the way it is proposed for large cities, where heavy equipment is used to spread and compact the waste in daily cells, and then to excavate, transport and apply daily cover, and leachate is managed with collection and treatment systems. This paper presents an alternative approach for small cities, known as the semi-mechanized trench method, which was developed in Villanueva, Honduras. In the semi-mechanized trench method a hydraulic excavator is used for 1-3 days to dig a trench that will last at least a month before it is filled with waste. Trucks can easily unload their wastes into the trench, and the wastes compact naturally due to semi-aerobic biodegradation, after which the trenches are refilled and covered. The exposed surface area is minimal since only the top surface of the wastes is exposed, the remainder being covered by the sides and bottom of the trench. The surplus material from trench excavation can be valorized for use as engineering fill onsite or off. The landfill in

  2. Disposable Diapers Are OK.

    Science.gov (United States)

    Poore, Patricia

    1992-01-01

    A personal account of measuring the pros and cons of disposable diaper usage leads the author to differentiate between a garbage problem and environmental problem. Concludes the disposable diaper issue is a political and economic issue with a local environmental impact and well within our abilities to manage. (MCO)

  3. Infiltration through layered-soil trench covers: Response to an extended period of rainfall

    Science.gov (United States)

    Larson, T. H.; Keefer, D. A.; Albrecht, K. A.; Cartwright, K.

    1988-12-01

    Four experimental waste disposal trench covers were constructed to test the effectiveness of layered-soil cover designs in reducing infiltration. Three covers each consisted of a layer of gravel between an overlying wick layer of compacted fine-grained material (either silt or loam) and a compacted loam base; the fourth consisted of compactd silt over a loam base. Capillary pressures were monitored at various depths within each cover during October through December, 1985, a period of high rainfall following a dry summer. Moisture movement in response to the rainfall was rapid within the upper layers of all four test covers, but was retained within the upper layers of the three wick-system trenches, despite variations in the design thickness and composition of the wick layers. In the wick systems, moisture did not enter the gravel until a threshold level of pressure approaching saturation was established in the wick layer. Once this level was reached, moisture moved into and through the gravel. This experiment demonstrates the functionality of field-scale wick systems.

  4. Infiltration through layered-soil trench covers: Response to an extended period of rainfall

    Science.gov (United States)

    Larson, T.H.; Keefer, D.A.; Albrecht, K.A.; Cartwright, K.

    1988-01-01

    Four experimental waste disposal trench covers were constructed to test the effectiveness of layered-soil cover designs in reducing infiltration. Three covers each consisted of a layer of gravel between an overlying wick layer of compacted fine-grained material (either silt or loam) and a compacted loam base; the fourth consisted of compactd silt over a loam base. Capillary pressures were monitored at various depths within each cover during October through December, 1985, a period of high rainfall following a dry summer. Moisture movement in response to the rainfall was rapid within the upper layers of all four test covers, but was retained within the upper layers of the three wick-system trenches, despite variations in the design thickness and composition of the wick layers. In the wick systems, moisture did not enter the gravel until a threshold level of pressure approaching saturation was established in the wick layer. Once this level was reached, moisture moved into and through the gravel. This experiment demonstrates the functionality of field-scale wick systems. ?? 1988.

  5. An oxide filled extended trench gate super junction MOSFET structure

    Institute of Scientific and Technical Information of China (English)

    Wang Cai-Lin; Sun Jun

    2009-01-01

    This paper proposes an oxide filled extended trench gate super junction (SJ) MOSFET structure to meet the need of higher frequency power switches application. Compared with the conventional trench gate SJ MOSFET, new structure has the smaller input and output capacitances, and the remarkable improvements in the breakdown voltage, on-resistance and switching speed. Furthermore, the SJ in the new structure can be realized by the existing trench etching and shallow angle implantation, which offers more freedom to SJ MOSFET device design and fabrication.

  6. Performance assessment and licensing issues for United States commercial near-surface low-level radioactive waste disposal facilities

    Energy Technology Data Exchange (ETDEWEB)

    Birk, S.M.

    1997-10-01

    The final objective of performance assessment for a near-surface LLW disposal facility is to demonstrate that potential radiological impacts for each of the human exposure pathways will not violate applicable standards. This involves determining potential pathways and specific receptor locations for human exposure to radionuclides; developing appropriate scenarios for each of the institutional phases of a disposal facility; and maintaining quality assurance and control of all data, computer codes, and documentation. The results of a performance assessment should be used to demonstrate that the expected impacts are expected to be less than the applicable standards. The results should not be used to try to predict the actual impact. This is an important distinction that results from the uncertainties inherent in performance assessment calculations. The paper discusses performance objectives; performance assessment phases; scenario selection; mathematical modeling and computer programs; final results of performance assessments submitted for license application; institutional control period; licensing issues; and related research and development activities.

  7. Wide-angle seismic survey in the trench-outer rise region of the central Japan Trench

    Science.gov (United States)

    Fujie, G.; Kodaira, S.; Iwamaru, H.; Shirai, T.; Dannowski, A.; Thorwart, M.; Grevemeyer, I.; Morgan, J. P.

    2015-12-01

    Dehydration process within the subducting oceanic plate and expelled water from there affect various subduction-zone processes, including arc volcanism and generation of earthquakes. This implies that the degree of hydration within the incoming oceanic plate just prior to subduction might be a key control factor on the regional variations in subduction zone processes like interplate earthquakes and arc volcanism. Recent advances in seismic structure studies in the trench-outer rise region of the Japan Trench have revealed that seismic velocities within the incoming oceanic plate become lower owing to the plate bending-related faulting, suggesting the hydration of the oceanic plate. If the degree of the oceanic plate hydration is one of key factors controlling the regional variations of the interplate earthquakes, the degree of the oceanic plate hydration just prior to subduction is expected to show the along-trench variation because the interplate seismicity in the forearc region of the Japan Trench show along-trench variations. However, we cannot discuss the along-trench variation of the incoming plate structure because seismic structure studies have been confined only to the northern Japan Trench so far.In 2014 and 2015, JAMSTEC and GEOMAR conducted wide-angle seismic surveys in the trench-outer rise region of the central Japan Trench to reveal the detailed seismic structure of the incoming oceanic plate. The western extension of our survey line corresponds to the epicenter of the 2011 M9 Tohoku earthquakes. We deployed 88 Ocean Bottom Seismometers (OBSs) at intervals of 6 km and shot a tuned air-gun array of R/V Kairei at 200 m spacing. In this presentation, we will show the overview of our seismic survey and present seismic structure models obtained by the data of mainly 2014 seismic survey together with the several OBS data from 2015 survey. The preliminary results show P-wave velocity (Vp) within the oceanic crust and mantle decreases toward the trench axis

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

    Science.gov (United States)

    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.

  9. Electrical resistivity tomography investigations on a paleoseismological trenching study

    Science.gov (United States)

    Berge, Meriç Aziz

    2014-10-01

    Two-dimensional electrical resistivity tomography (ERT) investigation was performed in a paleoseismological trenching study. Data acquisition strategies such as the selection of electrode configuration and electrode intervals of ERT application were investigated in this paper. The ERT results showed that the Wenner and Wenner-Schlumberger arrays yielded similar results for subsurface characteristics whereas the DD array provided slightly different results. The combined usage of these arrays produced satisfactory images of the subsurface resistivity distribution. In addition, the electrode spacing tests revealed that a suitable interpretation of subsurface geology can be obtained from a 5 m electrode interval. However, a suitable trenching location defined by successful 2D resistivity models was obtained for 1 m electrode spacing. Therefore, the comparison of the trench and ERT results was also possible. The results of trenching and ERT studies substantially support each other.

  10. Corrective action investigation plan: Cactus Spring Waste Trenches. Revision 2

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-02-01

    This Correction Action Investigation Plan (CAIP) contains environmental sample collection objectives and logic for the CAU No. 426, which includes the Cactus Spring Waste Trenches, CAS No. RG-08-001-RG-CS. The Cactus Spring Waste Trenches are located at the Tonopah Test Range (TTR) which is part of the Nellis Air Force Range, approximately 255 kilometers (km) (140 miles [mi]) northwest of Las Vegas, Nevada, by air. The purpose of this investigation is to generate sufficient data to establish the types of waste buried in the trenches, identify the presence and nature of contamination, determine the vertical extent of contaminant migration below the Cactus Spring Waste Trenches, and determine the appropriate course of action for the site. The potential courses of action for the site are clean closure, closure in place (with or without remediation), or no further action.

  11. Electrolytic decontamination of metal low level waste (LLW) and mixed low level waste (MLLW)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-11-01

    Metal objects resulting from ER activities were decontaminated using electrolytic methods. The project involved about 500 kg of ballistic test projectiles, 23 augers and drill heads, and 50 pieces of shrapnel containing lead. All objects were free-released and either reclaimed as scrap metal or reused. Electrolytic decontamination was proven to be an effective method to decontaminate metal waste objects to free-release standards. A cost analysis showed the process to be economical, especially when applied to decontamination of mixed waste, TRU waste, or when the recovered materials could be reused or recycled. The cost of decontamination of scrap iron is approximately equal to the cost of its land disposal as low level waste.

  12. Response of Microbial Community Function to Fluctuating Geochemical Conditions within a Legacy Radioactive Waste Trench Environment

    Science.gov (United States)

    Kinsela, Andrew S.; Bligh, Mark W.; Harrison, Jennifer J.; Payne, Timothy E.

    2017-01-01

    ABSTRACT During the 1960s, small quantities of radioactive materials were codisposed with chemical waste at the Little Forest Legacy Site (Sydney, Australia) in 3-meter-deep, unlined trenches. Chemical and microbial analyses, including functional and taxonomic information derived from shotgun metagenomics, were collected across a 6-week period immediately after a prolonged rainfall event to assess the impact of changing water levels upon the microbial ecology and contaminant mobility. Collectively, results demonstrated that oxygen-laden rainwater rapidly altered the redox balance in the trench water, strongly impacting microbial functioning as well as the radiochemistry. Two contaminants of concern, plutonium and americium, were shown to transition from solid-iron-associated species immediately after the initial rainwater pulse to progressively more soluble moieties as reducing conditions were enhanced. Functional metagenomics revealed the potentially important role that the taxonomically diverse microbial community played in this transition. In particular, aerobes dominated in the first day, followed by an increase of facultative anaerobes/denitrifiers at day 4. Toward the mid-end of the sampling period, the functional and taxonomic profiles depicted an anaerobic community distinguished by a higher representation of dissimilatory sulfate reduction and methanogenesis pathways. Our results have important implications to similar near-surface environmental systems in which redox cycling occurs. IMPORTANCE The role of chemical and microbiological factors in mediating the biogeochemistry of groundwaters from trenches used to dispose of radioactive materials during the 1960s is examined in this study. Specifically, chemical and microbial analyses, including functional and taxonomic information derived from shotgun metagenomics, were collected across a 6-week period immediately after a prolonged rainfall event to assess how changing water levels influence microbial

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  14. Plume head - trench interaction: impact on subduction dynamics

    Science.gov (United States)

    Betts, P. G.; Moresi, L. N.; Mason, W. G.; Willis, D.

    2013-12-01

    The geologic record provides numerous examples where plumes and their associated buoyancy swell have disrupted convergent plate margins. These interactions have produced a variety of responses in the overriding plate including transient episodes of arc amagmatism, transient episodes of crustal shortening followed by plume-related magmatism in the overriding plate. The latter observation implies the plume must have transitioned from the subducting plate to the overriding plate. We present several 3D Underworld numerical models of plume heads of variable dimension and buoyancy interacting with a subduction trench. The models indicate that plume heads impact enormously on trench geometry. Arcuate trenches are created as the trench retreats around the edges of the plume head, whereas trench advance occurs in front of the plume resulting in transient crustal shortening in the overriding plate. Stalling of subduction when the plume head impacts the trench causes slab windowing. The size of the slab window is dependent on the size and buoyancy of the plume. The creation of the slab window provides a potential conduit for plume migration to the overriding plate. Alternatively, the plume head may be transferred to the overriding plate as subduction is re-established behind the plume. Models with "strong" slabs, characterized by high yield strengths, display different behavior. Plume-heads are entrained in the slab and are subducted without the development of a slab window.

  15. Numerical models of trench migration in continental collision zones

    Directory of Open Access Journals (Sweden)

    V. Magni

    2012-03-01

    Full Text Available Continental collision is an intrinsic feature of plate tectonics. The closure of an oceanic basin leads to the onset of subduction of buoyant continental material, which slows down and eventually stops the subduction process. We perform a parametric study of the geometrical and rheological influence on subduction dynamics during the subduction of continental lithosphere. In 2-D numerical models of a free subduction system with temperature and stress-dependent rheology, the trench and the overriding plate move self-consistently as a function of the dynamics of the system (i.e. no external forces are imposed. This setup enables to study how continental subduction influences the trench migration. We found that in all models the trench starts to advance once the continent enters the subduction zone and continues to migrate until few million years after the ultimate slab detachment. Our results support the idea that the trench advancing is favoured and, in part provided by, the intrinsic force balance of continental collision. We suggest that the trench advance is first induced by the locking of the subduction zone and the subsequent steepening of the slab, and next by the sinking of the deepest oceanic part of the slab, during stretching and break-off of the slab. The amount of trench advancing ranges from 40 to 220 km and depends on the dip angle of the slab before the onset of collision.

  16. Special Analysis: Disposal Plan for Pit 38 at Technical Area 54, Area G

    Energy Technology Data Exchange (ETDEWEB)

    French, Sean B. [Los Alamos National Laboratory; Shuman, Rob [URS Coporation

    2012-06-26

    Los Alamos National Laboratory (LANL) generates radioactive waste as a result of various activities. Operational waste is generated from a wide variety of research and development activities including nuclear weapons development, energy production, and medical research; environmental restoration (ER), and decontamination and decommissioning (D&D) waste is generated as contaminated sites and facilities at LANL undergo cleanup or remediation. The majority of this waste is low-level radioactive waste (LLW) and is disposed of at the Technical Area 54 (TA-54), Area G disposal facility. U.S. Department of Energy (DOE) Order 435.1 (DOE, 2001) requires that radioactive waste be managed in a manner that protects public health and safety, and the environment. To comply with this order, DOE field sites must prepare site-specific radiological performance assessments for LLW disposal facilities that accept waste after September 26, 1988. Furthermore, sites are required to conduct composite analyses that account for the cumulative impacts of all waste that has been (or will be) disposed of at the facilities and other sources of radioactive material that may interact with the facilities. Revision 4 of the Area G performance assessment and composite analysis was issued in 2008 (LANL, 2008). These analyses estimate rates of radionuclide release from the waste disposed of at the facility, simulate the movement of radionuclides through the environment, and project potential radiation doses to humans for several on- and off-site exposure scenarios. The assessments are based on existing site and disposal facility data, and on assumptions about future rates and methods of waste disposal. The Area G disposal facility consists of Material Disposal Area (MDA) G and the Zone 4 expansion area. To date, disposal operations have been confined to MDA G and are scheduled to continue in that region until MDA G undergoes final closure at the end of 2013. Given its impending closure, efforts have

  17. Preliminary Project Execution Plan for the Remote-Handled Low-Level Waste Disposal Project

    Energy Technology Data Exchange (ETDEWEB)

    David Duncan

    2011-05-01

    This preliminary project execution plan (PEP) defines U.S. Department of Energy (DOE) project objectives, roles and responsibilities of project participants, project organization, and controls to effectively manage acquisition of capital funds for construction of a proposed remote-handled low-level waste (LLW) disposal facility at the Idaho National Laboratory (INL). The plan addresses the policies, requirements, and critical decision (CD) responsibilities identified in DOE Order 413.3B, 'Program and Project Management for the Acquisition of Capital Assets.' This plan is intended to be a 'living document' that will be periodically updated as the project progresses through the CD process to construction and turnover for operation.

  18. Application for a Permit to Operate a Class III Solid Waste Disposal Site at the Nevada Test Site Area 5 Asbestiform Low-Level Solid Waste Disposal Site

    Energy Technology Data Exchange (ETDEWEB)

    NSTec Environmental Programs

    2010-09-14

    The NTS solid waste disposal sites must be permitted by the state of Nevada Solid Waste Management Authority (SWMA). The SWMA for the NTS is the Nevada Division of Environmental Protection, Bureau of Federal Facilities (NDEP/BFF). The U.S. Department of Energy's National Nuclear Security Administration Nevada Site Office (NNSA/NSO) as land manager (owner), and National Security Technologies (NSTec), as operator, will store, collect, process, and dispose all solid waste by means that do not create a health hazard, a public nuisance, or cause impairment of the environment. NTS disposal sites will not be included in the Nye County Solid Waste Management Plan. The NTS is located approximately 105 kilometers (km) (65 miles [mi]) northwest of Las Vegas, Nevada (Figure 1). The U.S. Department of Energy (DOE) is the federal lands management authority for the NTS, and NSTec is the Management and Operations contractor. Access on and off the NTS is tightly controlled, restricted, and guarded on a 24-hour basis. The NTS has signs posted along its entire perimeter. NSTec is the operator of all solid waste disposal sites on the NTS. The Area 5 RWMS is the location of the permitted facility for the Solid Waste Disposal Site (SWDS). The Area 5 RWMS is located near the eastern edge of the NTS (Figure 2), approximately 26 km (16 mi) north of Mercury, Nevada. The Area 5 RWMS is used for the disposal of low-level waste (LLW) and mixed low-level waste. Many areas surrounding the RWMS have been used in conducting nuclear tests. A Notice of Intent to operate the disposal site as a Class III site was submitted to the state of Nevada on January 28, 1994, and was acknowledged as being received in a letter to the NNSA/NSO on August 30, 1994. Interim approval to operate a Class III SWDS for regulated asbestiform low-level waste (ALLW) was authorized on August 12, 1996 (in letter from Paul Liebendorfer to Runore Wycoff), with operations to be conducted in accordance with the &apos

  19. Trench Safety-Using a Qualitative Approach to Understand Barriers and Develop Strategies to Improve Trenching Practices.

    Science.gov (United States)

    Flynn, Michael A; Sampson, Julie M

    2012-06-01

    Despite efforts to ensure workplace safety and health, injuries and fatalities related to trenching and excavation remain alarmingly high in the construction industry. Because properly installed trenching protective systems can potentially reduce the significant number of trenching fatalities, there is clearly a need to identify the barriers to the use of these systems and to develop strategies to ensure these systems are utilized consistently. The current study reports on the results of focus groups with construction workers and safety management personnel to better understand these barriers and to identify solutions. The results suggest several factors, from poor planning to pressures from experienced workers and supervisors, which present barriers to safe trenching practices. Based on the results, it is recommended that safety trainings incorporate unique messages for new workers, experienced workers and management in an effort to motivate each group to work safely as well as provide them with solutions to overcome the identified barriers.

  20. Integrated Disposal Facility

    Data.gov (United States)

    Federal Laboratory Consortium — Located near the center of the 586-square-mile Hanford Site is the Integrated Disposal Facility, also known as the IDF.This facility is a landfill similar in concept...

  1. Integrated Disposal Facility FY2010 Glass Testing Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    Pierce, Eric M.; Bacon, Diana H.; Kerisit, Sebastien N.; Windisch, Charles F.; Cantrell, Kirk J.; Valenta, Michelle M.; Burton, Sarah D.; Serne, R Jeffrey; Mattigod, Shas V.

    2010-09-30

    Pacific Northwest National Laboratory was contracted by Washington River Protection Solutions, LLC to provide the technical basis for estimating radionuclide release from the engineered portion of the disposal facility (e.g., source term). Vitrifying the low-activity waste at Hanford is expected to generate over 1.6 × 105 m3 of glass (Puigh 1999). The volume of immobilized low-activity waste (ILAW) at Hanford is the largest in the DOE complex and is one of the largest inventories (approximately 0.89 × 1018 Bq total activity) of long-lived radionuclides, principally 99Tc (t1/2 = 2.1 × 105), planned for disposal in a low-level waste (LLW) facility. Before the ILAW can be disposed, DOE must conduct a performance assessement (PA) for the Integrated Disposal Facility (IDF) that describes the long-term impacts of the disposal facility on public health and environmental resources. As part of the ILAW glass testing program PNNL is implementing a strategy, consisting of experimentation and modeling, in order to provide the technical basis for estimating radionuclide release from the glass waste form in support of future IDF PAs. The purpose of this report is to summarize the progress made in fiscal year (FY) 2010 toward implementing the strategy with the goal of developing an understanding of the long-term corrosion behavior of low-activity waste glasses. The emphasis in FY2010 was the completing an evaluation of the most sensitive kinetic rate law parameters used to predict glass weathering, documented in Bacon and Pierce (2010), and transitioning from the use of the Subsurface Transport Over Reactive Multi-phases to Subsurface Transport Over Multiple Phases computer code for near-field calculations. The FY2010 activities also consisted of developing a Monte Carlo and Geochemical Modeling framework that links glass composition to alteration phase formation by 1) determining the structure of unreacted and reacted glasses for use as input information into Monte Carlo

  2. Sustainable sanitary landfills for neglected small cities in developing countries: the semi-mechanized trench method from Villanueva, Honduras.

    Science.gov (United States)

    Oakley, Stewart M; Jimenez, Ramón

    2012-12-01

    Open dumping is the most common practice for the disposal of urban solid wastes in the least developed regions of Africa, Asia and Latin America. Sanitary landfill design and operation has traditionally focused on large cities, but cities with fewer than 50,000 in population can comprise from 6% to 45% of a given country's total population. These thousands of small cities cannot afford to operate a sanitary landfill in the way it is proposed for large cities, where heavy equipment is used to spread and compact the waste in daily cells, and then to excavate, transport and apply daily cover, and leachate is managed with collection and treatment systems. This paper presents an alternative approach for small cities, known as the semi-mechanized trench method, which was developed in Villanueva, Honduras. In the semi-mechanized trench method a hydraulic excavator is used for 1-3 days to dig a trench that will last at least a month before it is filled with waste. Trucks can easily unload their wastes into the trench, and the wastes compact naturally due to semi-aerobic biodegradation, after which the trenches are refilled and covered. The exposed surface area is minimal since only the top surface of the wastes is exposed, the remainder being covered by the sides and bottom of the trench. The surplus material from trench excavation can be valorized for use as engineering fill onsite or off. The landfill in Villanueva has operated for 15 years, using a total land area of approximately 11 ha for a population that grew from 23,000 to 48,000, with a land requirement of 0.2m(2)/person year, a cover to waste ratio of 0.2, and an estimated soil surplus of 298,000 m(3) that is valorized and used onsite. The landfill has been operated solely by the municipality with an operational cost in 2010 estimated at US$4.60 per ton. A modified water balance analysis at Villanueva shows negligible leachate generation from covered trenches and 700 m(3)/yr (60 m(3)/ha yr) from the two open

  3. INORGANIC PLUME DELINEATION USING SURFACE HIGH RESOLUTION ELECTRICAL RESISTIVITY AT THE BC CRIBS & TRENCHES SITE HANFORD

    Energy Technology Data Exchange (ETDEWEB)

    BENECKE, M.W.

    2007-05-29

    A surface resistivity survey was conducted on the Hanford Site over a waste disposal trench that received a large volume of liquid inorganic waste. The objective of the survey was to map the extent of the plume that resulted from the disposal activities approximately 50 years earlier. The survey included six resistivity transects of at least 200m, where each transect provided two-dimensional profile information of subsurface electrical properties. The results of the survey indicated that a low resistivity plume resides at a depth of approximately 25-44 m below ground surface. The target depth was calibrated with borehole data of pore-water electrical conductivity. Due to the high correlation of the pore-water electrical conductivity to nitrate concentration and the high correlation of measured apparent resistivity to pore-water electrical conductivity, inferences were made that proposed the spatial distribution of the apparent resistivity was due to the distribution of nitrate. Therefore, apparent resistivities were related to nitrate, which was subsequently rendered in three dimensions to show that the nitrate likely did not reach the water table and the bounds of the highest concentrations are directly beneath the collection of waste sites.

  4. Movement of a tritium plume in shallow groundwater at a legacy low-level radioactive waste disposal site in eastern Australia.

    Science.gov (United States)

    Hughes, C E; Cendón, D I; Harrison, J J; Hankin, S I; Johansen, M P; Payne, T E; Vine, M; Collins, R N; Hoffmann, E L; Loosz, T

    2011-10-01

    Between 1960 and 1968 low-level radioactive waste was buried in a series of shallow trenches near the Lucas Heights facility, south of Sydney, Australia. Groundwater monitoring carried out since the mid 1970s indicates that with the exception of tritium, no radioactivity above typical background levels has been detected outside the immediate vicinity of the trenches. The maximum tritium level detected in ground water was 390 kBq/L and the median value was 5400 Bq/L, decay corrected to the time of disposal. Since 1968, a plume of tritiated water has migrated from the disposal trenches and extends at least 100 m from the source area. Tritium in rainfall is negligible, however leachate from an adjacent and fill represents a significant additional tritium source. Study data indicate variation in concentration levels and plume distribution in response to wet and dry climatic periods and have been used to determine pathways for tritium migration through the subsurface.

  5. Novel vertical silicon photodiodes based on salicided polysilicon trenched contacts

    Energy Technology Data Exchange (ETDEWEB)

    Kaminski, Yelena [Department of Chemical Engineering, Technion, Haifa (Israel); TowerJazz Ltd. Migdal Haemek (Israel); Shauly, Eitan [TowerJazz Ltd. Migdal Haemek (Israel); Paz, Yaron, E-mail: paz@tx.technion.ac.il [Department of Chemical Engineering, Technion, Haifa (Israel)

    2015-12-07

    The classical concept of silicon photodiodes comprises of a planar design characterized by heavily doped emitters. Such geometry has low collection efficiency of the photons absorbed close to the surface. An alternative, promising, approach is to use a vertical design. Nevertheless, realization of such design is technologically challenged, hence hardly explored. Herein, a novel type of silicon photodiodes, based on salicided polysilicon trenched contacts, is presented. These contacts can be prepared up to 10 μm in depth, without showing any leakage current associated with the increase in the contact area. Consequently, the trenched photodiodes revealed better performance than no-trench photodiodes. A simple two dimensional model was developed, allowing to estimate the conditions under which a vertical design has the potential to have better performance than that of a planar design. At large, the deeper the trench is, the better is the vertical design relative to the planar (up to 10 μm for silicon). The vertical design is more advantageous for materials characterized by short diffusion lengths of the carriers. Salicided polysilicon trenched contacts open new opportunities for the design of solar cells and image sensors. For example, these contacts may passivate high contact area buried contacts, by virtue of the conformity of polysilicon interlayer, thus lowering the via resistance induced recombination enhancement effect.

  6. Corrective action investigation plan: Cactus Spring Waste Trenches. Revision 2

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-02-01

    This Correction Action Investigation Plan (CAIP) contains environmental sample collection objectives and logic for the Corrective Action Unit No. 426, which includes the Cactus Spring Waste Trenches, located at the Tonopah Test Range. The purpose of this investigation is to generate sufficient data to establish the types of waste buried in the trenches, identify the presence and nature of contamination, determine the vertical extent of contaminant migration below the Cactus Spring Waste Trenches, and determine the appropriate course of action for the site. The potential courses of action for the site are clean closure, closure in place (with or without remediation), or no further action. The scope of this investigation will include drilling and collecting subsurface samples from within and below the trenches. Sampling locations will be biased toward the areas most likely to be contaminated. The Cactus Spring Waste Trenches Site is identified as one of three potential locations for buried, radioactively contaminated materials from the Double Tracks Test. This test was the first of four storage-transportation tests conducted in 1963 as part of Operation Roller Coaster. The experiment involved the use of live animals to assess the inhalation intake of a plutonium aerosol.

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

    Science.gov (United States)

    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.

  8. The New Britain trench and 149° embayment, Western Solomon Sea

    Science.gov (United States)

    Tiffin, D. L.; Davies, H. L.; Honza, E.; Lock, J.; Okuda, Y.

    1987-09-01

    The western New Britain Trench contains relatively thin sediment fill in the east, compared to the west where a sequence of thick turbidites is ponded behind a basement high in the trench axis, The trench trends toward Huon Gulf, but intersects the Trobriand Trench at an acute angle at the 149° Embayment, where both trenches end. Seismic structure west of the trench is incoherent, related to incipient collision of the Indian-Australia Plate and the South Bismarck Plate. The collision suture is marked by the Markham Canyon, continuous in its upper reaches with the Ramu-Markham Fault Zone on shore.

  9. Application for a Permit to Operate a Class III Solid Waste Disposal Site at the Nevada National Security Site Area 5 Asbestiform Low-Level Solid Waste Disposal Site

    Energy Technology Data Exchange (ETDEWEB)

    NSTec Environmental Programs

    2010-10-04

    The Nevada National Security Site (NNSS) is located approximately 105 km (65 mi) northwest of Las Vegas, Nevada. The U.S. Department of Energy National Nuclear Security Administration Nevada Site Office (NNSA/NSO) is the federal lands management authority for the NNSS and National Security Technologies, LLC (NSTec) is the Management and Operations contractor. Access on and off the NNSS is tightly controlled, restricted, and guarded on a 24-hour basis. The NNSS is posted with signs along its entire perimeter. NSTec is the operator of all solid waste disposal sites on the NNSS. The Area 5 Radioactive Waste Management Site (RWMS) is the location of the permitted facility for the Solid Waste Disposal Site (SWDS). The Area 5 RWMS is located near the eastern edge of the NNSS (Figure 1), approximately 26 km (16 mi) north of Mercury, Nevada. The Area 5 RWMS is used for the disposal of low-level waste (LLW) and mixed low-level waste. Many areas surrounding the RWMS have been used in conducting nuclear tests. The site will be used for the disposal of regulated Asbestiform Low-Level Waste (ALLW), small quantities of low-level radioactive hydrocarbon-burdened (LLHB) media and debris, LLW, LLW that contains Polychlorinated Biphenyl (PCB) Bulk Product Waste greater than 50 ppm that leaches at a rate of less than 10 micrograms of PCB per liter of water, and small quantities of LLHB demolition and construction waste (hereafter called permissible waste). Waste containing free liquids, or waste that is regulated as hazardous waste under the Resource Conservation and Recovery Act (RCRA) or state-of-generation hazardous waste regulations, will not be accepted for disposal at the site. Waste regulated under the Toxic Substances Control Act (TSCA) that will be accepted at the disposal site is regulated asbestos-containing materials (RACM) and PCB Bulk Product Waste greater than 50 ppm that leaches at a rate of less than 10 micrograms of PCB per liter of water. The term asbestiform is

  10. SEMICONDUCTOR DEVICES: Trench gate IGBT structure with floating P region

    Science.gov (United States)

    Mengliang, Qian; Zehong, Li; Bo, Zhang; Zhaoji, Li

    2010-02-01

    A new trench gate IGBT structure with a floating P region is proposed, which introduces a floating P region into the trench accumulation layer controlled IGBT (TAC-IGBT). The new structure maintains a low on-state voltage drop and large forward biased safe operating area (FBSOA) of the TAC-IGBT structure while reduces the leakage current and improves the breakdown voltage. In addition, it enlarges the short circuit safe operating area (SCSOA) of the TAC-IGBT, and is simple in fabrication and design. Simulation results indicate that, for IGBT structures with a breakdown voltage of 1200 V, the leakage current of the new trench gate IGBT structure is one order of magnitude lower than the TAC-IGBT structure and the breakdown voltage is 150 V higher than the TAC-IGBT.

  11. Interplate coupling along the Java trench from CGPS observation

    Science.gov (United States)

    Meilano, I.; Kuncoro, H.; Susilo, S.; Efendi, J.; Abidin, H. Z.; Nugraha, A. D.; Widiyantoro, S.

    2014-12-01

    Interplate seismogenic zones along the Java trench were estimated by using continuous GPS observation from South of Lampung in the west to Lombok Island in the east. The observation period starting from 2010 to 2013 with more than 60 CGPS observation stations. The GPS analysis indicates that present-day deformation of Java Island is controlled by rotation of Sunda land, extension in the southern Strait of Sunda, postseismic deformation of the 2006 earthquake and the coupling between Indo-Australian plate and Sunda land. Strain rate solutions indicate compression in the south of Java Island. Using elastic dislocation theory the estimated interplate seismozonic coupling in the Java trench is about 50 percent in the sunda strait, smaller in the south west java and become larger to the east. Slip deficit on subduction interface has important implication for seismic hazard of Java Island. Keywords: CGPS observation, Interplate Seismogenic, Java Trench

  12. Indentation tectonics in the accretionary wedge of middle Manila Trench

    Institute of Scientific and Technical Information of China (English)

    LI Jiabiao; JIN Xianglong; RUAN Aiguo; WU Shimin; WU Ziyin; LIU Jianhua

    2004-01-01

    Based on the multibeam morpho-tectonic analysis of the Manila Trench accretionary wedge and its indentation tectonics and the contrasting researches with other geological and geophysical data, three tectonic zones of the wedge are established, faulting features, tectonic distribution and stress mechanism for the indentation tectonicsareanalyzed,oblique subduction along Manila Trench with convergent stress of NW55. Is presented, and the relationship of the ceasing of Eastern Subbasin spreading of South China Sea Basin to the formation of subduction zone of Manila Trench is discussed. By the model analysis and regional research, it is found that the seamount subduction along Manila Trenchoes not lead to the erosion of the accretionary wedge and the oblique subduction actually is a NWWtrending obducfion of Luzon micro-plate that results from the NWW-trending displacement of the Philippine Sea plate.

  13. A comparison of trenched plot techniques for partitioning soil respiration

    Energy Technology Data Exchange (ETDEWEB)

    Bond-Lamberty, Benjamin; Bronson, Dustin; Bladyka, Emma; Gower, Stith T.

    2011-07-16

    Partitioning the soil surface CO{sub 2} flux (R{sub S}) flux is an important step in understanding ecosystem-level carbon cycling, given that R{sub S} is poorly constrained and its source components may have different responses to climate change. Trenched plots are a classic method of separating the R{sub S} source fluxes, but labor-intensive and may cause considerable disturbance to the soil environment. This study tested if various methods of plant suppression in trenched plots affected R{sub S} fluxes, quantified the R{sub S} response to soil temperature and moisture changes, and estimated the heterotrophic contribution to R{sub S}. It was performed in a boreal black spruce (Picea mariana) plantation, using a complete randomized design, during the 2007 growing season (May-November). Trenched plots had significantly lower R{sub S} than control plots, with differences appearing {approx}100 days after trenching; spatial variability doubled after trenching but then declined throughout the experiment. Most trenching treatments had significantly lower (by {approx}0.5 {mu}mol m{sup -2} s{sup -1}) R{sub S} than the controls, and there was no significant difference in R{sub S} among the various trenching treatments. Soil temperature at 2 cm explained more R{sub S} variability than did 10-cm temperature or soil moisture. Temperature sensitivity (Q10) declined in the control plots from {approx}2.6 (at 5 C) to {approx}1.6 (at 15 C); trenched plots values were higher, from 3.1 at 5 C to 1.9 at 15 C. We estimated R{sub S} for the study period to be 241 {+-} 40 g C m{sup -2}, with roots contributing 64% of R{sub S} after accounting for fine root decay, and 293 g C m{sup -2} for the entire year. These findings suggest that laborious hand weeding of vegetation may be usefully replaced by other methods, easing future studies of this large and poorly-understood carbon flux.

  14. Waste disposal package

    Science.gov (United States)

    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.

  15. Nanomaterial disposal by incineration

    Science.gov (United States)

    As nanotechnology-based products enter into widespread use, nanomaterials will end up in disposal waste streams that are ultimately discharged to the environment. One possible end-of-life scenario is incineration. This review attempts to ascertain the potential pathways by which ...

  16. Chemical Stockpile Disposal Program

    Energy Technology Data Exchange (ETDEWEB)

    Krummel, J.R.; Policastro, A.J.; Olshansky, S.J.; McGinnis, L.D.

    1990-10-01

    As part of the Chemical Stockpile Disposal Program mandated by Public Law 99--145 (Department of Defense Authorization Act), an independent review is presented of the US Army Phase I environmental report for the disposal program at the Umatilla Depot Activity (UMDA) in Hermiston, Oregon. The Phase I report addressed new and additional concerns not incorporated in the final programmatic environmental impact statement (FPEIS). Those concerns were addressed by examining site-specific data for the Umatilla Depot Activity and by recommending the scope and content of a more detailed site-specific study. This independent review evaluates whether the new site-specific data presented in the Phase I report would alter the decision in favor of on-site disposal that was reached in the FPEIS, and whether the recommendations for the scope and content of the site-specific study are adequate. Based on the methods and assumptions presented in the FPEIS, the inclusion of more detailed site-specific data in the Phase I report does not change the decision reached in the FPEIS (which favored on-site disposal at UMDA). It is recommended that alternative assumptions about meteorological conditions be considered and that site-specific data on water, ecological, socioeconomic, and cultural resources; seismicity; and emergency planning and preparedness be considered explicitly in the site-specific EIS decision-making process. 7 refs., 1 fig.

  17. Chemical Stockpile Disposal Program

    Energy Technology Data Exchange (ETDEWEB)

    Krummel, J.R.; Policastro, A.J.; Olshansky, S.J.; McGinnis, L.D.

    1990-10-01

    As part of the Chemical Stockpile Disposal Program mandated by Public Law 99--145 (Department of Defense Authorization Act), an independent review is presented of the US Army Phase I environmental report for the disposal program at the Pine Bluff Arsenal (PBA) in Arkansas. The Phase I report addressed new and additional concerns not incorporated in the final programmatic environmental impact statement (FPEIS). Those concerns were addressed by examining site-specific data for the PBA and by recommending the scope and content of a more detailed site- specific study. This dependent review evaluates whether the new site-specific data presented in the Phase I report would alter the decision in favor of on-site disposal that was reached in the FPEIS, and whether the recommendations for the scope and content of the site-specific study are adequate. Based on the methods and assumptions presented in the FPEIS, the inclusion of more detailed site-specific data in the Phase I report does not change the decision reached in the FPEIS (which favored on-site disposal at PBA). It is recommended that alternative assumptions about meteorological conditions be considered and that site-specific data on water, ecological, socioeconomic, and cultural resources, and emergency planning and preparedness be considered explicitly in the site-specific EIS decision-making process. 13 refs., 1 fig.

  18. Characterization of 618-11 solid waste burial ground, disposed waste, and description of the waste generating facilities

    Energy Technology Data Exchange (ETDEWEB)

    Hladek, K.L.

    1997-10-07

    The 618-11 (Wye or 318-11) burial ground received transuranic (TRTJ) and mixed fission solid waste from March 9, 1962, through October 2, 1962. It was then closed for 11 months so additional burial facilities could be added. The burial ground was reopened on September 16, 1963, and continued operating until it was closed permanently on December 31, 1967. The burial ground received wastes from all of the 300 Area radioactive material handling facilities. The purpose of this document is to characterize the 618-11 solid waste burial ground by describing the site, burial practices, the disposed wastes, and the waste generating facilities. This document provides information showing that kilogram quantities of plutonium were disposed to the drum storage units and caissons, making them transuranic (TRU). Also, kilogram quantities of plutonium and other TRU wastes were disposed to the three trenches, which were previously thought to contain non-TRU wastes. The site burial facilities (trenches, caissons, and drum storage units) should be classified as TRU and the site plutonium inventory maintained at five kilograms. Other fissile wastes were also disposed to the site. Additionally, thousands of curies of mixed fission products were also disposed to the trenches, caissons, and drum storage units. Most of the fission products have decayed over several half-lives, and are at more tolerable levels. Of greater concern, because of their release potential, are TRU radionuclides, Pu-238, Pu-240, and Np-237. TRU radionuclides also included slightly enriched 0.95 and 1.25% U-231 from N-Reactor fuel, which add to the fissile content. The 618-11 burial ground is located approximately 100 meters due west of Washington Nuclear Plant No. 2. The burial ground consists of three trenches, approximately 900 feet long, 25 feet deep, and 50 feet wide, running east-west. The trenches constitute 75% of the site area. There are 50 drum storage units (five 55-gallon steel drums welded together

  19. Trench dynamics: Effects of dynamically migrating trench on subducting slab morphology and characteristics of subduction zones systems

    Science.gov (United States)

    Yoshida, Masaki

    2017-07-01

    Understanding the mechanisms of trench migration (retreat or advance) is crucial to characterizing the driving forces of Earth's tectonics plates, the origins of subducting slab morphologies in the deep mantle, and identifying the characteristics of subduction zones systems, which are among the fundamental issues of solid Earth science. A series of numerical simulations of mantle convection, focusing on plate subduction in a three-dimensional (3-D) regional spherical shell coordinate system, was performed to examine subduction zone characteristics, including geodynamic relationships among trench migration, back-arc stress, and slab morphology. The results show that a subducting slab tends to deflect around the base of the mantle transition zone and form a sub-horizontal slab because its front edge (its 'toe') is subject to resistance from the highly viscous lower mantle. As the sub-horizontal slab starts to penetrate into the lower mantle from its 'heel,' the toe of the slab is drawn into the lower mantle. The results for models with dynamically migrating trenches suggest that trench retreat is the dynamically self-consistent phenomenon in trench migration. The reason for this is that the strong lateral mantle flow that is generated as a sequence of events leading from corner flow at the subduction initiation to return flow of the formation of a sub-horizontal slab in the shallower part of mantle wedge produces the retreat of the subducting slab. In fact, a 'mantle suction force,' which is generated in the mantle wedge to fill space left by the retreating subducting plate, is enhanced by the subsequent trench retreat. Even when upwelling flow with significant positive buoyancy originates just above a mantle phase boundary at a depth of 410 km (as inferred from independent seismic tomographic, geodynamic, geochemical, and mineral physics), reaches the base of the overriding plate, and the overriding plate is slightly thinned, lithospheric stress tends to be

  20. Plutonium Mobility Studies: 216-Z-9 Trench Sample Analysis Results

    Energy Technology Data Exchange (ETDEWEB)

    Cantrell, Kirk J.; Geiszler, Keith N.; Arey, Bruce W.

    2008-09-05

    detectable concentrations of extractable Pu and Am. Water extracts from samples containing high concentrations of TBP suggest that if the TBP degradation products DBP and MBP are available in these sediments, they do not significantly increase the extractability of Pu or Am. Geochemical modeling results suggest that the concentrations of Am in water in contact with these sediments is not controlled by the solubility of Am(OH)3(c), but rather by desorption of Am that has been previously adsorbed to the sediments during the period of active wastewater disposal. Sediment extracts that had measureable concentrations of Am only occurred in samples that were fairly acidic (pH 4.3 to 4.6), indicating that Am will remain effectively sequestered to sediments when pH conditions approach those of normal Hanford groundwater (mildly alkaline, ~ pH 8). The geochemical modeling results indicate that Pu in acidic extracts is significantly undersaturated with respect to PuO2(am). However, recent reviews of Pu solubility and redox reactions suggest that the data used for these calculations is incomplete (Neck et al. 2007a, 2007b). The results of Neck et al. (2007a, 2007b) suggest that Pu concentrations in solutions in contact with the 216-Z-9 Trench sediment samples might be controlled by a mixed valent solid phase [(PuV)2x(PuIV)1-2xO2+x(am)] with various dissolved Pu(V) complexes and Pu(IV)O2(am) colloids or nanoclusters being the dominant species in solution for typical Hanford groundwater conditions. Adsorption is likely to have a major impact on the mobility of these species (Neck et al. 2007a, 2007b; Clark et al. 2006; Kaplan et al. 2006; Powell et al. 2005). Further research is planned to verify these hypotheses.

  1. Development of Particle-in-Cell Simulation in a Two Dimensional Trench Geometry

    CERN Document Server

    Lin, Tai-Lu

    2016-01-01

    A two dimensional electrostatic Particle-in-Cell simulation code is developed to investigate anisotropy of ions in a trench geometry for plasma etching. The numerical simulation results suggest that if the trench width is larger than Debye length scale, anisotropy can be lost due to potential development across the trench. Furthermore, the effects of ion charge build up on the trench bottom is investigated, which can degrade the anisotropy.

  2. EARTHSAWtm IN-SITU CONTAINMENT OF PITS AND TRENCHES

    Energy Technology Data Exchange (ETDEWEB)

    Ernest E. Carter, P.E.

    2002-09-20

    EarthSaw{trademark} is a proposed technology for construction of uniform high quality barriers under and around pits and trenches containing buried radioactive waste without excavating or disturbing the waste. The method works by digging a deep vertical trench around the perimeter of a site, filling that trench with high specific gravity grout sealant, and then cutting a horizontal bottom pathway at the base of the trench with a simple cable saw mechanism. The severed block of earth becomes buoyant in the grout and floats on a thick layer of grout, which then cures into an impermeable barrier. The ''Interim Report on task 1 and 2'' which is incorporated into this report as appendix A, provided theoretical derivations, field validation of formulas, a detailed quantitative engineering description of the technique, engineering drawings of the hardware, and a computer model of how the process would perform in a wide variety of soil conditions common to DOE waste burial sites. The accomplishments of task 1 and 2 are also summarized herein Task 3 work product provides a comprehensive field test plan in Appendix B and a health and safety plan in Appendix C and proposal for a field-scale demonstration of the EarthSaw barrier technology. The final report on the subcontracted stress analysis is provided in Appendix D. A copy of the unified computer model is provided as individual non-functional images of each sheet of the spreadsheet and separately as a Microsoft Excel 2000 file.

  3. Recent Radiation Test Results for Trench Power MOSFETs

    Science.gov (United States)

    Lauenstein, Jean-Marie; Casey, Megan C.; Wilcox, Edward P.; Phan, Anthony M.; Kim, Hak S.; Topper, Alyson D.; Ladbury, Raymond L.; Label, Kenneth A.

    2017-01-01

    Single-event effect (SEE) radiation test results are presented for various trench-gate power MOSFETs. The heavy-ion response of the first (and only) radiation-hardened trench-gate power MOSFET is evaluated: the manufacturer SEE response curve is verified and importantly, no localized dosing effects are measured, distinguishing it from other, non-hardened trench-gate power MOSFETs. Evaluations are made of n-type commercial and both n- and p-type automotive grade trench-gate device using ions comparable to of those on the low linear energy transfer (LET) side of the iron knee of the galactic cosmic ray spectrum, to explore suitability of these parts for missions with higher risk tolerance and shorter duration, such as CubeSats. Part-to-part variability of SEE threshold suggests testing with larger sample sizes and applying more aggressive derating to avoid on-orbit failures. The n-type devices yielded expected localized dosing effects including when irradiated in an unbiased (0-V) configuration, adding to the challenge of inserting these parts into space flight missions.

  4. Diaper area and disposable diapers.

    Science.gov (United States)

    Erasala, G N; Romain, C; Merlay, I

    2011-01-01

    Since the 1960s, cloth diapers have been replaced by disposable diapers. The evolution of healthier skin in the diaper area has been demonstrated in parallel to that of disposable diapers. The improvements of disposable diapers--fit, dryness, comfort--have been based on the understanding of factors playing a role in the development of diaper dermatitis.

  5. Geological disposal of nuclear waste

    Energy Technology Data Exchange (ETDEWEB)

    1979-01-01

    Fourteen papers dealing with disposal of high-level radioactive wastes are presented. These cover disposal in salt deposits, geologic deposits and marine disposal. Also included are papers on nuclear waste characterization, transport, waste processing technology, and safety analysis. All of these papers have been abstracted and indexed. (AT)

  6. In situ respiration measurements of megafauna in the Kermadec Trench

    Science.gov (United States)

    Nunnally, Clifton C.; Friedman, Jason R.; Drazen, Jeffrey C.

    2016-12-01

    The aim of this paper is to measure metabolic rates of megafauna living in depths greater than 6000 m. Echinoderms, actinarians and a polychaete were captured by remotely operated vehicle (ROV) and inserted into respiration chambers in situ at depths of 4049 m, 7140 m and 8074 m in the region of the Kermadec Trench SW Pacific Ocean. Hadal research has moved into a new frontier as technological improvements now allow for a meticulous investigation of trench ecology in depths greater than 6000 m. The development of an in situ respirometer for use in these studies was deployed in the Kermadec Trench to obtain the first ever rates of basal metabolic rates of hadal megafauna. Typical deep-sea experiments of individual animal physiology must deal with covarying factors of pressure, temperature, light and food supply in this study investigated the effects of pressure and increased food supply on overall animal metabolism. In the Kermadec Trench, holothurian respiration rates (n=4), 0.079±0.011 (mean±SE) μmol-O2 g-1 h-1, were higher than those captured at abyssal depths (n=2), 0.018±0.002 μmol-O2 g-1h-1, in the same region (p<0.001). When Q10 adjusted to a common temperature of 2.5 °C trench holothurian respiration rates ranged between 0.068 and 0.119 μmol-O2 g-1 h-1. Anemone respiration rates were remarkably similar between abyssal and hadal specimens, 0.110 and 0.111 μmol-O2 g-1 h-1, respectively. Our results on echinoderm respiration when corrected for temperature and mass fall below the slope regression when compared with other in situ measurements at shallower ocean depths.

  7. Space disposal of nuclear wastes

    Science.gov (United States)

    Priest, C. C.; Nixon, R. F.; Rice, E. E.

    1980-01-01

    The DOE has been studying several options for nuclear waste disposal, among them space disposal, which NASA has been assessing. Attention is given to space disposal destinations noting that a circular heliocentric orbit about halfway between Earth and Venus is the reference option in space disposal studies. Discussion also covers the waste form, showing that parameters to be considered include high waste loading, high thermal conductivity, thermochemical stability, resistance to leaching, fabrication, resistance to oxidation and to thermal shock. Finally, the Space Shuttle nuclear waste disposal mission profile is presented.

  8. The Remote Handled Immobilization Low Activity Waste Disposal Facility Environmental Permits & Approval Plan

    Energy Technology Data Exchange (ETDEWEB)

    DEFFENBAUGH, M.L.

    2000-08-01

    The purpose of this document is to revise Document HNF-SD-ENV-EE-003, ''Permitting Plan for the Immobilized Low-Activity Waste Project, which was submitted on September 4, 1997. That plan accounted for the interim storage and disposal of Immobilized-Low Activity Waste at the existing Grout Treatment Facility Vaults (Project W-465) and within a newly constructed facility (Project W-520). Project W-520 was to have contained a combination of concrete vaults and trenches. This document supersedes that plan because of two subsequent items: (1) A disposal authorization that was received on October 25, 1999, in a U. S. Department of Energy-Headquarters, memorandum, ''Disposal Authorization Statement for the Department of Energy Hanford site Low-Level Waste Disposal facilities'' and (2) ''Breakthrough Initiative Immobilized Low-Activity Waste (ILAW) Disposal Alternative,'' August 1999, from Lucas Incorporated, Richland, Washington. The direction within the U. S. Department of Energy-Headquarters memorandum was given as follows: ''The DOE Radioactive Waste Management Order requires that a Disposal authorization statement be obtained prior to construction of new low-level waste disposal facility. Field elements with the existing low-level waste disposal facilities shall obtain a disposal authorization statement in accordance with the schedule in the complex-wide Low-Level Waste Management Program Plan. The disposal authorization statement shall be issued based on a review of the facility's performance assessment and composite analysis or appropriate CERCLA documentation. The disposal authorization shall specify the limits and conditions on construction, design, operations, and closure of the low-level waste facility based on these reviews. A disposal authorization statement is a part of the required radioactive waste management basis for a disposal facility. Failure to obtain a disposal authorization statement

  9. Variably-saturated groundwater modeling for optimizing managed aquifer recharge using trench infiltration

    Science.gov (United States)

    Heilweil, Victor M.; Benoit, Jerome; Healy, Richard W.

    2015-01-01

    Spreading-basin methods have resulted in more than 130 million cubic meters of recharge to the unconfined Navajo Sandstone of southern Utah in the past decade, but infiltration rates have slowed in recent years because of reduced hydraulic gradients and clogging. Trench infiltration is a promising alternative technique for increasing recharge and minimizing evaporation. This paper uses a variably saturated flow model to further investigate the relative importance of the following variables on rates of trench infiltration to unconfined aquifers: saturated hydraulic conductivity, trench spacing and dimensions, initial water-table depth, alternate wet/dry periods, and number of parallel trenches. Modeling results showed (1) increased infiltration with higher hydraulic conductivity, deeper initial water tables, and larger spacing between parallel trenches, (2) deeper or wider trenches do not substantially increase infiltration, (3) alternating wet/dry periods result in less overall infiltration than keeping the trenches continuously full, and (4) larger numbers of parallel trenches within a fixed area increases infiltration but with a diminishing effect as trench spacing becomes tighter. An empirical equation for estimating expected trench infiltration rates as a function of hydraulic conductivity and initial water-table depth was derived and can be used for evaluating feasibility of trench infiltration in other hydrogeologic settings

  10. Ocean bottom seismic and tsunami network along the Japan Trench

    Science.gov (United States)

    Uehira, K.; Kanazawa, T.; Noguchi, S.; Aoi, S.; Kunugi, T.; Matsumoto, T.; Okada, Y.; Sekiguchi, S.; Shiomi, K.; Shinohara, M.; Yamada, T.

    2012-12-01

    Huge tsunami, which was generated by the 2011 off the Pacific Coast of Tohoku Earthquake of M9 subduction zone earthquake, attacked the coastal areas in the north-eastern Japan and gave severe casualties (about 20,000 people) and property damages in the areas. The present tsunami warning system, based on land seismic observation data, did not work effectively in the case of the M9 earthquake. For example, real tsunami height was higher than that of forecast by this system. It is strongly acknowledged that marine observation data is necessary to make tsunami height estimation more accurately. Therefore, new ocean bottom observation project has started in 2011 that advances the countermeasures against earthquake and tsunami disaster related to subduction zone earthquake and outer rise earthquake around Japan Trench and Kuril Trench. A large scale ocean bottom cabled observation network is scheduled to be deployed around Japan Trench and Kuril Trench by 2015. The network is consisted of 154 ocean bottom observation stations. Ocean bottom fiber optic cables, about 5100 km in total length, connect the stations to land. Observation stations with tsunami meters and seismometers will be placed on the seafloor off Hokkaido, off Tohoku and off Kanto, in a spacing of about 30 km almost in the direction of East-West (perpendicular to the trench axis) and in a spacing of about 50 - 60 km almost in the direction of North-South (parallel to the trench axis). Two or more sets of tsunami meters and seismometers will be installed in one station for redundancy. Two sets of three component servo accelerometers, a set of three component quartz type accelerometers (frequency outputs), a set of three component velocity seismometers will be installed, and two sets of quartz type depth sensors (frequency outputs) will be installed as tsunami meters. Tsunami data and seismometer data will be digitized at sampling frequency of 10 Hz and 100 Hz, respectively, and will be added clock

  11. An ongoing large submarine landslide at the Japan trench

    Science.gov (United States)

    Nitta, S.; Kasaya, T.; Miura, S.; Kawamura, K.

    2013-12-01

    This paper deals with an active submarine landslide on a landward trench slope in the Japan trench. Studied area is located on the upper terrace ranging from 400 to 1200 m in water depth, off Sendai, northeast Japan. We have surveyed in detail the seabed topography using a multi narrow beam (hereafter MBES) and a subbottom profiler (hereafter SBP) during the cruise MR12-E02 of R/V Mirai. The survey lines were 12 lines in N-S, and 3 lines in E-W, and situated in the region from 141°45'E, 37°40'N to 142°33'E, 38°32'N. Moreover, we used multi-channel seismic profile by the cruise KR04-10 of R/V Kairei in the interpretation of the SBP results. In general, horseshoe-shaped depressions of about 100 km wide along the trench slope are arrayed along the Japan trench. It has thought that they were formed by large submarine landslides, but we could not understand critically the relationship between the depressions and the submarine landslides. Based on the survey results, we found signals of an active submarine landslide in the depression as follows. 1) We observed arcuate-shaped lineaments, which are sub-parallel to a horseshoe-shaped depression. The lineaments concentrate in the south region from 38°N at about 20 km wide. These lineaments are formed by deformation structures as anticlines, synclines and normal fault sense displacements. 2) Most of the synclines and anticlines are not buried to form the lineaments. 3) Normal faults cutting about 1 km deep are observed in a multi-channel seismic profile. The normal faults are located just below the arcuate-shaped lineaments, and are tilted eastward being the downslope direction. It indicates a large submarine landslide. We concluded that the arcuate-shaped lineaments were generated by surface sediment movement with the submarine landsliding. We think that the submarine landslide of about 20 km wide and about 1 km thick move continuously down the landward trench slope. This would be the formation process of the horseshoe

  12. Near-Field Hydrology Data Package for the Integrated Disposal Facility 2005 Performance Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, Philip D.; Saripalli, Prasad; Freedman, Vicky L.

    2004-06-25

    CH2MHill Hanford Group, Inc. (CHG) is designing and assessing the performance of an Integrated Disposal Facility (IDF) to receive immobilized low-activity waste (ILAW), Low-Level and Mixed Low-Level Wastes (LLW/MLLW), and the Waste Treatment Plant (WTP) melters used to vitrify the ILAW. The IDF Performance Assessment (PA) assesses the performance of the disposal facility to provide a reasonable expectation that the disposal of the waste is protective of the general public, groundwater resources, air resources, surface water resources, and inadvertent intruders. The PA requires prediction of contaminant migration from the facilities, which is expected to occur primarily via the movement of water through the facilities and the consequent transport of dissolved contaminants in the pore water of the vadose zone. Pacific Northwest National Laboratory (PNNL) assists CHG in its performance assessment activities. One of PNNL’s tasks is to provide estimates of the physical, hydraulic, and transport properties of the materials comprising the disposal facilities and the disturbed region around them. These materials are referred to as the near-field materials. Their properties are expressed as parameters of constitutive models used in simulations of subsurface flow and transport. In addition to the best-estimate parameter values, information on uncertainty in the parameter values and estimates of the changes in parameter values over time are required to complete the PA. These parameter estimates and information were previously presented in a report prepared for the 2001 ILAW PA. This report updates the parameter estimates for the 2005 IDF PA using additional information and data collected since publication of the earlier report.

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

    Energy Technology Data Exchange (ETDEWEB)

    Alexander, J.A. [Univ. of Maine, Orono, ME (United States)

    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.

  14. HLW Disposal System Development

    Energy Technology Data Exchange (ETDEWEB)

    Choi, J. W.; Choi, H. J.; Lee, J. Y. (and others)

    2007-06-15

    A KRS is suggested through design requirement analysis of the buffer and the canister which are the constituent of disposal system engineered barrier and HLW management plans are proposed. In the aspect of radionuclide retention capacity, the thickness of the buffer is determined 0.5m, the shape to be disc and ring and the dry density to be 1.6 g/cm{sup 3}. The maximum temperature of the buffer is below 100 .deg. which meets the design requirement. And bentonite blocks with 5 wt% of graphite showed more than 1.0 W/mK of thermal conductivity without the addition of sand. The result of the thermal analysis for proposed double-layered buffer shows that decrease of 7 .deg. C in maximum temperature of the buffer. For the disposal canister, the copper for the outer shell material and cast iron for the inner structure material is recommended considering the results analyzed in terms of performance of the canisters and manufacturability and the geochemical properties of deep groundwater sampled from the research area with granite, salt water intrusion, and the heavy weight of the canister. The results of safety analysis for the canister shows that the criticality for the normal case including uncertainty is the value of 0.816 which meets subcritical condition. Considering nation's 'Basic Plan for Electric Power Demand and Supply' and based on the scenario of disposing CANDU spent fuels in the first phase, the disposal system that the repository will be excavated in eight phases with the construction of the Underground Research Laboratory (URL) beginning in 2020 and commissioning in 2040 until the closure of the repository is proposed. Since there is close correlation between domestic HLW management plans and front-end/back-end fuel cycle plans causing such a great sensitivity of international environment factor, items related to assuring the non-proliferation and observing the international standard are showed to be the influential factor and acceptability

  15. Study of Reduced Graphene Oxide for Trench Schottky Diode

    Science.gov (United States)

    Samihah Khairir, Nur; Rofei Mat Hussin, Mohd; Nasir, Iskhandar Md; Mukhter Uz-Zaman, A. S. M.; Fazlida Hanim Abdullah, Wan; Sabirin Zoolfakar, Ahmad

    2015-11-01

    This paper presents the study of reduced Graphene Oxide (RGO) for trench Schottky diode by replacing conventional metal layer that forms schottky contact with a nanostructured carbon thin film via Reduced Graphene Oxide (RGO) technique. The RGO was synthesis by chemical exfoliation in which modified Hummer's method was approached. It was then deposited on the trench schottky pattern substrate by pressurized spray coating. The sample was then characterized by FESEM, Raman Spectroscopy and I-V test. The results of FESEM and Raman showed good characteristics and well deposited nanostructures of RGO flakes. The two-point I-V test showed that the samples have a low turn-on voltage and a higher break-down voltage, which is better than the conventional schottky diode used in the market.

  16. Water-rich bending faults at the Middle America Trench

    Science.gov (United States)

    Naif, Samer; Key, Kerry; Constable, Steven; Evans, Rob L.

    2015-09-01

    The portion of the Central American margin that encompasses Nicaragua is considered to represent an end-member system where multiple lines of evidence point to a substantial flux of subducted fluids. The seafloor spreading fabric of the incoming Cocos plate is oriented parallel to the trench such that flexural bending at the outer rise optimally reactivates a dense network of normal faults that extend several kilometers into the upper mantle. Bending faults are thought to provide fluid pathways that lead to serpentinization of the upper mantle. While geophysical anomalies detected beneath the outer rise have been interpreted as broad crustal and upper mantle hydration, no observational evidence exists to confirm that bending faults behave as fluid pathways. Here we use seafloor electromagnetic data collected across the Middle America Trench (MAT) offshore of Nicaragua to create a comprehensive electrical resistivity image that illuminates the infiltration of seawater along bending faults. We quantify porosity from the resistivity with Archie's law and find that our estimates for the abyssal plain oceanic crust are in good agreement with independent observations. As the Cocos crust traverses the outer rise, the porosity of the dikes and gabbros progressively increase from 2.7% and 0.7% to 4.8% and 1.7%, peaking within 20 km of the trench axis. We conclude that the intrusive crust subducts twice as much pore water as previously thought, significantly raising the flux of fluid to the seismogenic zone and the mantle wedge.

  17. Echo chamber and trench warfare dynamics in online debates.

    Science.gov (United States)

    Karlsen, Rune; Steen-Johnsen, Kari; Wollebæk, Dag; Enjolras, Bernard

    2017-06-01

    In this article, we take issue with the claim by Sunstein and others that online discussion takes place in echo chambers, and suggest that the dynamics of online debates could be more aptly described by the logic of 'trench warfare', in which opinions are reinforced through contradiction as well as confirmation. We use a unique online survey and an experimental approach to investigate and test echo chamber and trench warfare dynamics in online debates. The results show that people do indeed claim to discuss with those who hold opposite views from themselves. Furthermore, our survey experiments suggest that both confirming and contradicting arguments have similar effects on attitude reinforcement. Together, this indicates that both echo chamber and trench warfare dynamics - a situation where attitudes are reinforced through both confirmation and disconfirmation biases - characterize online debates. However, we also find that two-sided neutral arguments have weaker effects on reinforcement than one-sided confirming and contradicting arguments, suggesting that online debates could contribute to collective learning and qualification of arguments.

  18. Control of paleoshorelines by trench forebulge uplift, Loyalty Islands

    Science.gov (United States)

    Dickinson, William R.

    2013-07-01

    Unlike most tropical Pacific islands, which lie along island arcs or hotspot chains, the Loyalty Islands between New Caledonia and Vanuatu owe their existence and morphology to the uplift of pre-existing atolls on the flexural forebulge of the New Hebrides Trench. The configuration and topography of each island is a function of distance from the crest of the uplifted forebulge. Both Maré and Lifou are fully emergent paleoatolls upon which ancient barrier reefs form highstanding annular ridges that enclose interior plateaus representing paleolagoon floors, whereas the partially emergent Ouvea paleoatoll rim flanks a drowned remnant lagoon. Emergent paleoshoreline features exposed by island uplift include paleoreef flats constructed as ancient fringing reefs built to past low tide levels and emergent tidal notches incised at past high tide levels. Present paleoshoreline elevations record uplift rates of the islands since last-interglacial and mid-Holocene highstands in global and regional sea levels, respectively, and paleoreef stratigraphy reflects net Quaternary island emergence. The empirical uplift rates vary in harmony with theoretical uplift rates inferred from the different positions of the islands in transit across the trench forebulge at the trench subduction rate. The Loyalty Islands provide a case study of island environments controlled primarily by neotectonics.

  19. Color Image of Snow White Trenches and Scraping

    Science.gov (United States)

    2008-01-01

    This image was acquired by NASA's Phoenix Mars Lander's Surface Stereo Imager on the 31st Martian day of the mission, or Sol 31 (June 26, 2008), after the May 25, 2008 landing. This image shows the trenches informally called 'Snow White 1' (left), 'Snow White 2' (right), and within the Snow White 2 trench, the smaller scraping area called 'Snow White 3.' The Snow White 3 scraped area is about 5 centimeters (2 inches) deep. The dug and scraped areas are within the diggiing site called 'Wonderland.' The Snow White trenches and scraping prove that scientists can take surface soil samples, subsurface soil samples, and icy samples all from one unit. Scientists want to test samples to determine if some ice in the soil may have been liquid in the past during warmer climate cycles. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is led by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver

  20. Chemical stimulants of leaf-trenching by cabbage loopers: natural products, neurotransmitters, insecticides, and drugs.

    Science.gov (United States)

    Dussourd, David E

    2003-09-01

    Larvae of the cabbage looper, Trichoplusia ni (Lepidoptera: Noctuidae), often transect leaves with a narrow trench before eating the distal section. The trench reduces larval exposure to exudates, such as latex, during feeding. Plant species that do not emit exudate, such as Plantago lanceolata, are not trenched. However, if exudate is applied to a looper's mouth during feeding on P. lanceolata, the larva will often stop and cut a trench. Dissolved chemicals can be similarly applied and tested for effectiveness at triggering trenching. With this assay, I have documented that lactucin from lettuce latex (Lactuca sativa), myristicin from parsley oil (Petroselinum crispum), and lobeline from cardinal flower (Lobelia cardinalis) elicit trenching. These compounds are the first trenching stimulants reported. Several other constituents of lettuce and parsley, including some phenylpropanoids, monoterpenes, and furanocoumarins had little or no activity. Cucurbitacin E glycoside found in cucurbits, another plant family trenched by cabbage loopers, also was inactive. Lactucin, myristicin, and lobeline all affect the nervous system of mammals, with lobeline acting specifically as an antagonist of nicotinic acetylcholine receptors. To determine if cabbage loopers respond selectively to compounds active at acetylcholine synapses, I tested several neurotransmitters, insecticides, and drugs with known neurological activity, many of which triggered trenching. Active compounds included dopamine, serotonin, the insecticide imidacloprid, and various drugs such as ipratropium, apomorphine, buspirone, and metoclopramide. These results document that noxious plant chemicals trigger trenching, that loopers respond to different trenching stimulants in different plants, that diverse neuroactive chemicals elicit the behavior, and that feeding deterrents are not all trenching stimulants. The trenching assay offers a novel approach for identifying defensive plant compounds with potential uses

  1. Computational Film Cooling Effectiveness of Dual Trench Configuration on Flat Plate at Moderate Blowing Ratios

    Institute of Scientific and Technical Information of China (English)

    Antar M.M.Abdala; Qun Zheng; Fifi N.M.Elwekeel; Ping Dong

    2013-01-01

    In the present work,computational simulations was made using ANSYS CFX to predict the improvements in film cooling performance with dual trench.Dual-trench configuration consists of two trenches together,one wider trench and the other is narrow trench that extruded from the wider one.Several blowing ratios in the range (0.5∶5) were investigated.The pitch-to-diameter ratio of 2.775 is used.By using the dual trench configuration,the coolant jet impacted the trench wall two times allowing increasing the spreading of coolant laterally in the trench,reducing jet velocity and jet completely covered on the surface.The results indicate that this configuration increased adiabatic effectiveness as blowing ratio increased.The spatially averaged adiabatic effectiveness reached 57.6% for at M=2.No observed film blow-offat all blowing ratios.The adiabatic film effectiveness of dual trench case outperformed the narrow trench case,laidback fan-shaped hole,fan-shaped hole and cylinder hole at different blowing ratios.

  2. Lakeview, Oregon, Disposal Site

    Energy Technology Data Exchange (ETDEWEB)

    Linard, Joshua [USDOE Office of Legacy Management (LM), Washington, DC (United States); Hall, Steve [Navarro Research and Engineering, Inc., Oak Ridge, TN (United States)

    2016-03-01

    9.1 Compliance Summary The Lakeview, Oregon, Uranium Mill Tailings Radiation Control Act (UMTRCA) Title I Disposal Site was inspected September 16 and 17, 2015. Other than some ongoing concern with erosion-control rock riprap degradation, the disposal cell was in good condition. Some minor fence repairs and vegetation removal, and minor erosion repair work along the west site fence is planned. Inspectors identified no other maintenance needs or cause for a follow-up or contingency inspection. Disposal cell riprap is evaluated annually to ensure continued long-term protection of the cell from erosion during a severe precipitation event. Degradation of the rock riprap was first observed at the site in the mid-1990s. Rock gradation monitoring of the riprap on the west side slope has been performed as part of the annual inspection since 1997 to determine the mean diameter (D50) value. As prescribed by the monitoring procedure, the rock monitoring is routinely conducted at random locations. However, at the U.S. Nuclear Regulatory Commission’s (NRC’s) request, the 2015 rock monitoring approach deviated from the normal procedure by using a pre-established monitoring grid in a subset area of the west side slope. This changed the monitoring approach from random sampling to biased sampling. The D50 value measured during the 2015 gradation monitoring is 2.39 inches, which falls below the original D50 design size range of 2.7–3.9 inches for the Type B size side slope riprap. At NRC’s request, rock durability monitoring was added to the gradation monitoring in 2009 to monitor durability by rock type. Results of the 2015 durability monitoring showed that74 percent of the total rock sampled is durability class code A rock with an assigned durability class of “highly durable” or durability class code B “durable” rock, and that over 90 percent of the 3-inch or larger rock is durability class code A or B. The rock durability

  3. Evaluation of Groundwater Impacts to Support the National Environmental Policy Act Environmental Assessment for the INL Remote-Handled Low-Level Waste Disposal Project

    Energy Technology Data Exchange (ETDEWEB)

    Annette Schafer; Arthur S. Rood; A. Jeffrey Sondrup

    2011-12-01

    The groundwater impacts have been analyzed for the proposed RH-LLW disposal facility. A four-step analysis approach was documented and applied. This assessment compared the predicted groundwater ingestion dose to the more restrictive of either the 25 mrem/yr all pathway dose performance objective, or the maximum contaminant limit performance objective. The results of this analysis indicate that the groundwater impacts for either proposed facility location are expected to be less than the performance objectives. The analysis was prepared to support the NEPA-EA for the top two ranking of the proposed RH-LLW sites. As such, site-specific conditions were incorporated for each set of results generated. These site-specific conditions were included to account for the transport of radionuclides through the vadose zone and through the aquifer at each site. Site-specific parameters included the thickness of vadose zone sediments and basalts, moisture characteristics of the sediments, and aquifer velocity. Sorption parameters (Kd) were assumed to be very conservative values used in Track II analysis of CERCLA sites at INL. Infiltration was also conservatively assumed to represent higher rates corresponding to disturbed soil conditions. The results of this analysis indicate that the groundwater impacts for either proposed facility location are expected to be less than the performance objectives.

  4. Evaluation of Groundwater Impacts to Support the National Environmental Policy Act Environmental Assessment for the INL Remote-Handled Low-Level Waste Disposal Project

    Energy Technology Data Exchange (ETDEWEB)

    Annette Schafer; Arthur S. Rood; A. Jeffrey Sondrup

    2010-08-01

    The groundwater impacts have been analyzed for the proposed RH-LLW disposal facility. A four-step analysis approach was documented and applied. This assessment compared the predicted groundwater ingestion dose to the more restrictive of either the 25 mrem/yr all pathway dose performance objective, or the maximum contaminant limit performance objective. The results of this analysis indicate that the groundwater impacts for either proposed facility location are expected to be less than the performance objectives. The analysis was prepared to support the NEPA-EA for the top two ranking of the proposed RH-LLW sites. As such, site-specific conditions were incorporated for each set of results generated. These site-specific conditions were included to account for the transport of radionuclides through the vadose zone and through the aquifer at each site. Site-specific parameters included the thickness of vadose zone sediments and basalts, moisture characteristics of the sediments, and aquifer velocity. Sorption parameters (Kd) were assumed to be very conservative values used in Track II analysis of CERCLA sites at INL. Infiltration was also conservatively assumed to represent higher rates corresponding to disturbed soil conditions. The results of this analysis indicate that the groundwater impacts for either proposed facility location are expected to be less than the performance objectives.

  5. Evaluation of Groundwater Impacts to Support the National Environmental Policy Act Environmental Assessment for the INL Remote-Handled Low-Level Waste Disposal Project

    Energy Technology Data Exchange (ETDEWEB)

    Annette Schafer; Arthur S. Rood; A. Jeffrey Sondrup

    2011-08-01

    The groundwater impacts have been analyzed for the proposed RH-LLW disposal facility. A four-step analysis approach was documented and applied. This assessment compared the predicted groundwater ingestion dose to the more restrictive of either the 25 mrem/yr all pathway dose performance objective, or the maximum contaminant limit performance objective. The results of this analysis indicate that the groundwater impacts for either proposed facility location are expected to be less than the performance objectives. The analysis was prepared to support the NEPA-EA for the top two ranking of the proposed RH-LLW sites. As such, site-specific conditions were incorporated for each set of results generated. These site-specific conditions were included to account for the transport of radionuclides through the vadose zone and through the aquifer at each site. Site-specific parameters included the thickness of vadose zone sediments and basalts, moisture characteristics of the sediments, and aquifer velocity. Sorption parameters (Kd) were assumed to be very conservative values used in Track II analysis of CERCLA sites at INL. Infiltration was also conservatively assumed to represent higher rates corresponding to disturbed soil conditions. The results of this analysis indicate that the groundwater impacts for either proposed facility location are expected to be less than the performance objectives.

  6. Nuclear waste disposal in space

    Science.gov (United States)

    Burns, R. E.; Causey, W. E.; Galloway, W. E.; Nelson, R. W.

    1978-01-01

    Work on nuclear waste disposal in space conducted by the George C. Marshall Space Flight Center, National Aeronautics and Space Administration, and contractors are reported. From the aggregate studies, it is concluded that space disposal of nuclear waste is technically feasible.

  7. Melter Disposal Strategic Planning Document

    Energy Technology Data Exchange (ETDEWEB)

    BURBANK, D.A.

    2000-09-25

    This document describes the proposed strategy for disposal of spent and failed melters from the tank waste treatment plant to be built by the Office of River Protection at the Hanford site in Washington. It describes program management activities, disposal and transportation systems, leachate management, permitting, and safety authorization basis approvals needed to execute the strategy.

  8. Disposable diapers: safe and effective.

    Science.gov (United States)

    Singh, Namita; Purthi, P K; Sachdev, Anupam; Gupta, Suresh

    2003-09-01

    Nappy rash is a common problem in infants due to their thinner skin, wetness, heat and friction under cloth nappy, fecal enzymes and alkaline urine. The disposable diapers containing Super Absorbent Material (SAM) reduce the incidence of nappy rash. SAM quickly absorbs urine and keeps the skin dry. Also disposable diapers prevent fecal contamination by absorbing the urine and containing stools.

  9. Integrated Disposal Facility Risk Assessment

    Energy Technology Data Exchange (ETDEWEB)

    MANN, F. M.

    2003-06-03

    An environmental risk assessment associated with the disposal of projected Immobilized Low-Activity Waste, solid wastes and failed or decommissioned melters in an Integrated Disposal Facility was performed. Based on the analyses all performance objectives associated with the groundwater, air, and intruder pathways were met.

  10. Korean Reference HLW Disposal System

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Heui Joo; Lee, J. Y.; Kim, S. S. (and others)

    2008-03-15

    This report outlines the results related to the development of Korean Reference Disposal System for High-level radioactive wastes. The research has been supported around for 10 years through a long-term research plan by MOST. The reference disposal method was selected via the first stage of the research during which the technical guidelines for the geological disposal of HLW were determined too. At the second stage of the research, the conceptual design of the reference disposal system was made. For this purpose the characteristics of the reference spent fuels from PWR and CANDU reactors were specified, and the material and specifications of the canisters were determined in term of structural analysis and manufacturing capability in Korea. Also, the mechanical and chemical characteristics of the domestic Ca-bentonite were analyzed in order to supply the basic design parameters of the buffer. Based on these parameters the thermal and mechanical analysis of the near-field was carried out. Thermal-Hydraulic-Mechanical behavior of the disposal system was analyzed. The reference disposal system was proposed through the second year research. At the final third stage of the research, the Korean Reference disposal System including the engineered barrier, surface facilities, and underground facilities was proposed through the performance analysis of the disposal system.

  11. 2D and 3D stability analysis of slurry trench in frictional/cohesive soil

    Institute of Scientific and Technical Information of China (English)

    Chang-yu HAN; Jin-jian CHEN; Jian-hua WANG; Xiao-he XIA

    2013-01-01

    A 2D and 3D kinematically admissible rotational failure mechanism is presented for homogeneous slurry trenches in frictional/cohesive soils.Analytical approaches are derived to obtain the upper bounds on slurry trench stability in the strict framework of limit analysis.It is shown that the factor of safety from a 3D analysis will be greater than that from a 2D analysis.Compared with the limit equilibrium method,the limit analysis method yields an unconservative estimate on the safety factors.A set of examples are presented in a wide range of parameters for 2D and 3D homogeneous slurry trenches.The factor of safety increases with increasing slurry and soil bulk density ratio,cohesion,friction angle,and with decreasing slurry level depth and trench depth ratio,trench width and depth ratio.It is convenient to assess the safety for the homogeneous slurry trenches in practical applications.

  12. SEMICONDUCTOR DEVICES Process optimization of a deep trench isolation structure for high voltage SOI devices

    Science.gov (United States)

    Kuiying, Zhu; Qinsong, Qian; Jing, Zhu; Weifeng, Sun

    2010-12-01

    The process reasons for weak point formation of the deep trench on SOI wafers have been analyzed in detail. An optimized trench process is also proposed. It is found that there are two main reasons: one is over-etching laterally of the silicon on the surface of the buried oxide caused by a fringe effect; and the other is the slow growth rate of the isolation oxide in the concave silicon corner of the trench bottom. In order to improve the isolation performance of the deep trench, two feasible ways for optimizing the trench process are proposed. The improved process thickens the isolation oxide and rounds sharp silicon corners at their weak points, increasing the applied voltage by 15-20 V at the same leakage current. The proposed new trench isolation process has been verified in the foundry's 0.5-μm HV SOI technology.

  13. Engineering geology of waste disposal

    Energy Technology Data Exchange (ETDEWEB)

    Bentley, S.P. [ed.] [University of Wales, Cardiff (United Kingdom). School of Engineering

    1996-12-31

    This volume covers a wide spectrum of activities in the field of waste disposal. These activities range from design of new landfills and containment properties of natural clays to investigation, hazard assessment and remediation of existing landfills. Consideration is given to design criteria for hard rock quarries when used for waste disposal. In addition, an entire section concerns the geotechnics of underground repositories. This covers such topics as deep drilling, in situ stress measurement, rock mass characterization, groundwater flows and barrier design. Engineering Geology of Waste Disposal examines, in detail, the active role of engineering geologists in the design of waste disposal facilities on UK and international projects. The book provides an authoritative mix of overviews and detailed case histories. The extensive spectrum of papers will be of practical value to those geologists, engineers and environmental scientists who are directly involved with waste disposal. (UK).

  14. Scaling Rule for Very Shallow Trench IGBT toward CMOS Process Compatibility

    OpenAIRE

    2012-01-01

    Deep trench gate is used for latest IGBT to improve device performance. By large difference from deep submicron CMOS structure, there is no process compatibility among CMOS device and trench gate IGBT. We propose IGBT scaling rule for shrinking IGBT cell structure both horizontally and vertically. The scaling rule is theoretically delivered by structure based equations. Device performance improvement was also predicted by TCAD simulations even with very shallow trench gate. The rule enables t...

  15. Operating Modes and Power Considerations of Microhollow Cathode Discharge Devices with Elongated Trenches

    Science.gov (United States)

    2012-01-24

    of earlier MHCD designs [20,23]. The design of an elongated-trench MHCD for reforming capi- talizes on the benefits of general microchannel reactors ...both design aspects incorporated into the elon- gated trench devices. The elongated trench was conceptually based on earlier microchannel reactors ...exploring them as chemical reactors [1,3,5,43,44]. Increased understanding of the conditions that ensure stable microplasma operation is critical to

  16. Special Analysis of Transuranic Waste in Trench T04C at the Area 5 Radioactive Waste Management Site, Nevada Test Site, Nye County, Nevada, Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    Greg Shott, Vefa Yucel, Lloyd Desotell

    2008-05-01

    This Special Analysis (SA) was prepared to assess the potential impact of inadvertent disposal of a limited quantity of transuranic (TRU) waste in classified Trench 4 (T04C) within the Area 5 Radioactive Waste Management Site (RWMS) at the Nevada Test Site (NTS). The Area 5 RWMS is a low-level radioactive waste disposal site in northern Frenchman Flat on the Nevada Test Site (NTS). The Area 5 RWMS is regulated by the U.S. Department of Energy (DOE) under DOE Order 435.1 and DOE Manual (DOE M) 435.1-1. The primary objective of the SA is to evaluate if inadvertent disposal of limited quantities of TRU waste in a shallow land burial trench at the Area 5 RWMS is in compliance with the existing, approved Disposal Authorization Statement (DAS) issued under DOE M 435.1-1. In addition, supplemental analyses are performed to determine if there is reasonable assurance that the requirements of Title 40, Code of Federal Regulations (CFR), Part 191, Environmental Radiation Protection Standards for Management and Disposal of Spent Nuclear Fuel, High-Level, and Transuranic Radioactive Wastes, can be met. The 40 CFR 191 analyses provide supplemental information regarding the risk to human health and the environment of leaving the TRU waste in T04C. In 1989, waste management personnel reviewing classified materials records discovered that classified materials buried in trench T04C at the Area 5 RWMS contained TRU waste. Subsequent investigations determined that a total of 102 55-gallon drums of TRU waste from Rocky Flats were buried in trench T04C in 1986. The disposal was inadvertent because unclassified records accompanying the shipment indicated that the waste was low-level. The exact location of the TRU waste in T04C was not recorded and is currently unknown. Under DOE M 435.1-1, Chapter IV, Section P.5, low-level waste disposal facilities must obtain a DAS. The DAS specifies conditions that must be met to operate within the radioactive waste management basis, consisting of a

  17. Steady film flow over 2D topography with air inclusion formed inside the trench

    Science.gov (United States)

    Tsamopoulos, John; Varchanis, Stylianos; Dimakopoulos, Yannis

    2016-11-01

    Liquid film flow along an inclined, solid substrate featuring periodic rectangular trenches may either completely wet the trench floor (Wenzel state) or pin on the entrance and exit corners of the trench (Cassie state) or assume any other configuration in between these two extremes. In the intermediate cases a second gas-liquid interface inside the trench is formed, which adheres to the walls of the trench forming two three-phase contact lines, and encloses a different amount of air under different physical conditions. The Galerkin finite element method is used to solve the Navier-Stokes equations in a physical domain, which is adaptively re-meshed. Multiple steady solutions, connected by turning points and transcritical bifurcations as well as isolated solution branches, are revealed by pseudo arc-length continuation. Two possible cases of a single air inclusion inside the trench are examined. The penetration of the liquid inside the trench is enhanced primarily by increasing either the wettability of the substrate or the capillarity or by decreasing the flow rate. Flow hysteresis may occur when the liquid does not penetrate deep enough inside the trench leading to different flow patterns. The interplay of inertia, viscous, gravity and capillary forces along with substrate wettability determines the volume of the air encapsulated in the trench and the extent of free surface deformation. GSRT of Greece via the program "Excellence" and the LIMMAT foundation.

  18. Hadal disturbance in the Japan Trench induced by the 2011 Tohoku-Oki earthquake

    DEFF Research Database (Denmark)

    Oguri, K.; Kawamura, K.; Sakaguchi, A.

    2013-01-01

    In situ video observations and sediment core samplings were performed at two hadal sites in the Japan Trench on July, 2011, four months after the Tohoku-Oki earthquake. Video recordings documented dense nepheloid layers extending similar to 30-50 m above the sea bed. At the trench axis, benthic...... macrofauna was absent and dead organisms along with turbid downslope current were observed. The top 31 cm of sediment in the trench axis revealed three recent depositions events characterized by elevated Cs-137 levels and alternating sediment densities. At 4.9 km seaward from the trench axis, little...

  19. Trench curvature and deformation of the subducting lithosphere

    Science.gov (United States)

    Schettino, Antonio; Tassi, Luca

    2012-01-01

    The subduction of oceanic lithosphere is generally accompanied by downdip and lateral deformation. The downdip component of strain is associated with external forces that are applied to the slab during its sinking, namely the gravitational force and the mantle resistance to penetration. Here, we present theoretical arguments showing that a tectonic plate is also subject to a predictable amount of lateral deformation as a consequence of its bending along an arcuate trench zone, independently from the long-term physical processes that have determined the actual curvature of the subduction zone. In particular, we show that the state of lateral strain and the lateral strain rate of a subducting slab depend from geometric and kinematic parameters, such as trench curvature, dip function and subduction velocity. We also demonstrate that the relationship between the state of lateral strain in a subducting slab and the geometry of bending at the corresponding active margin implies a small component of lateral shortening at shallow depths, and may include large extensional lateral deformation at intermediate depths, whereas a state of lateral mechanical equilibrium can only represent a localized exception. Our formulation overcomes the flaws of the classic 'ping-pong ball' model for the bending of the lithosphere at subduction zones, which lead to severe discrepancies with the observed geometry and style of deformation of the modern subducting slabs. A study of the geometry and seismicity of eight modern subduction zones is performed, to assess the validity of the theoretical relationship between trench curvature, slab dip function, and lateral strain rate. The strain pattern within the eight present-day slabs, which is reconstructed through an analysis of Harvard CMT solutions, shows that tectonic plates cannot be considered as flexible-inextensible spherical caps, whereas the lateral intraslab deformation which is accommodated through seismic slip can be explained in terms

  20. Trench sampling report Salmon Site Lamar County, Mississippi

    Energy Technology Data Exchange (ETDEWEB)

    1994-07-01

    This report describes trench excavation and sample-collection activities conducted by IT Corporation (IT) as part of the ongoing Remedial Investigation and Feasibility Study at the Salmon Site, Lamar County, Mississippi (DOE, 1992). During construction, operation, and closure of the site wastes of unknown composition were buried in pits on site. Surface-geophysical field investigations were conducted intermittently between November 1992 and October 1993 to identify potential waste-burial sites and buried metallic materials. The geophysical investigations included vertical magnetic gradient, electromagnetic conductivity, electromagnetic in-phase component, and ground-penetrating radar surveys. A number of anomalies identified by the magnetic gradiometer survey in the Reynolds Electrical & Engineering Co., Inc., (REECo) pits area indicated buried metallic objects. All of the anomalies were field checked to determine if any were caused by surface features or debris. After field checking, 17 anomalies were still unexplained; trenching was planned to attempt to identify their sources. Between December 8, 1993, and December 17, 1993, 15 trenches were excavated and soil samples were collected at the anomalies. Samples were collected, placed in 250- and 500-milliliter (m{ell}) amber glass containers, and shipped on ice to IT Analytical Services (ITAS) in St. Louis, Missouri, using standard IT chain-of-custody procedures. The samples were analyzed for various chemical and radiological parameters. Data validation has not been conducted on any of the samples. During excavation and sampling, soil samples were also collected by IT for the MSDEQ and the Mississippi Department of Radiological Health, in accordance with their instructions, and delivered into their custody.

  1. 3-D visualisation of palaeoseismic trench stratigraphy and trench logging using terrestrial remote sensing and GPR - combining techniques towards an objective multiparametric interpretation

    Science.gov (United States)

    Schneiderwind, S.; Mason, J.; Wiatr, T.; Papanikolaou, I.; Reicherter, K.

    2015-09-01

    Two normal faults on the Island of Crete and mainland Greece were studied to create and test an innovative workflow to make palaeoseismic trench logging more objective, and visualise the sedimentary architecture within the trench wall in 3-D. This is achieved by combining classical palaeoseismic trenching techniques with multispectral approaches. A conventional trench log was firstly compared to results of iso cluster analysis of a true colour photomosaic representing the spectrum of visible light. Passive data collection disadvantages (e.g. illumination) were addressed by complementing the dataset with active near-infrared backscatter signal image from t-LiDAR measurements. The multispectral analysis shows that distinct layers can be identified and it compares well with the conventional trench log. According to this, a distinction of adjacent stratigraphic units was enabled by their particular multispectral composition signature. Based on the trench log, a 3-D-interpretation of GPR data collected on the vertical trench wall was then possible. This is highly beneficial for measuring representative layer thicknesses, displacements and geometries at depth within the trench wall. Thus, misinterpretation due to cutting effects is minimised. Sedimentary feature geometries related to earthquake magnitude can be used to improve the accuracy of seismic hazard assessments. Therefore, this manuscript combines multiparametric approaches and shows: (i) how a 3-D visualisation of palaeoseismic trench stratigraphy and logging can be accomplished by combining t-LiDAR and GRP techniques, and (ii) how a multispectral digital analysis can offer additional advantages and a higher objectivity in the interpretation of palaeoseismic and stratigraphic information. The multispectral datasets are stored allowing unbiased input for future (re-)investigations.

  2. 3-D visualisation of palaeoseismic trench stratigraphy and trench logging using terrestrial remote sensing and GPR – combining techniques towards an objective multiparametric interpretation

    Directory of Open Access Journals (Sweden)

    S. Schneiderwind

    2015-09-01

    Full Text Available Two normal faults on the Island of Crete and mainland Greece were studied to create and test an innovative workflow to make palaeoseismic trench logging more objective, and visualise the sedimentary architecture within the trench wall in 3-D. This is achieved by combining classical palaeoseismic trenching techniques with multispectral approaches. A conventional trench log was firstly compared to results of iso cluster analysis of a true colour photomosaic representing the spectrum of visible light. Passive data collection disadvantages (e.g. illumination were addressed by complementing the dataset with active near-infrared backscatter signal image from t-LiDAR measurements. The multispectral analysis shows that distinct layers can be identified and it compares well with the conventional trench log. According to this, a distinction of adjacent stratigraphic units was enabled by their particular multispectral composition signature. Based on the trench log, a 3-D-interpretation of GPR data collected on the vertical trench wall was then possible. This is highly beneficial for measuring representative layer thicknesses, displacements and geometries at depth within the trench wall. Thus, misinterpretation due to cutting effects is minimised. Sedimentary feature geometries related to earthquake magnitude can be used to improve the accuracy of seismic hazard assessments. Therefore, this manuscript combines multiparametric approaches and shows: (i how a 3-D visualisation of palaeoseismic trench stratigraphy and logging can be accomplished by combining t-LiDAR and GRP techniques, and (ii how a multispectral digital analysis can offer additional advantages and a higher objectivity in the interpretation of palaeoseismic and stratigraphic information. The multispectral datasets are stored allowing unbiased input for future (re-investigations.

  3. Trench warfare!: fitting photons for fine-feature fabrication

    Science.gov (United States)

    Kuijten, Jan P.; Conley, Will; Socha, Robert J.; van de Goor, Stephan; Hsu, Stephen; Smith, Dave; Oliveras, Marc; Strozenski, Kirk

    2001-09-01

    The challenge is developing imaging solutions for 180 nm trench lithography that provides maximum overlapping process windows for imaging through pitch. The issue has been addressed first; through simulation to optimize illumination, secondly; with experimentation and the collection of data through dose and focus for a number of pitch sequences with several illumination conditions for each CD. Our problem is how to handle the comparison of many ED windows and still be able to determine which set of conditions provide the best result, the POP factor (Pitch Optimization Process) was determined. The authors will review the POP factor to demonstrate a possible new technique in the calculation of multiple pitch ED windows.

  4. Geological disposal system development

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Chul Hyung; Kuh, J. E.; Kim, S. K. and others

    2000-04-01

    Spent fuel inventories to be disposed of finally and design base spent fuel were determined. Technical and safety criteria for a geological repository system in Korea were established. Based on the properties of spent PWR and CANDU fuels, seven repository alternatives were developed and the most promising repository option was selected by the pair-wise comparison method from the technology point of view. With this option preliminary conceptual design studies were carried out. Several module, e.g., gap module, congruent release module were developed for the overall assessment code MASCOT-K. The prominent overseas databases such as OECD/NEA FEP list were are fully reviewed and then screened to identify the feasible ones to reflect the Korean geo-hydrological conditions. In addition to this the well known scenario development methods such as PID, RES were reviewed. To confirm the radiological safety of the proposed KAERI repository concept the preliminary PA was pursued. Thermo-hydro-mechanical analysis for the near field of repository were performed to verify thermal and mechanical stability for KAERI repository system. The requirements of buffer material were analyzed, and based on the results, the quantitative functional criteria for buffer material were established. The hydraulic and swelling property, mechanical properties, and thermal conductivity, the organic carbon content, and the evolution of pore water chemistry were investigated. Based on the results, the candidate buffer material was selected.

  5. Disposable diapers: a hygienic alternative.

    Science.gov (United States)

    Kamat, Maithili; Malkani, Ram

    2003-11-01

    The use of disposable diapers has offered improved health care benefits. Urine and fecal matter leakage from the cloth nappies and the hand-to-mouth behavior in infants leads to many illnesses with a feco-oral mode of transmission. Also, the tender skin of the infant is more prone to nappy rash. The modern age disposable diapers, when compared to cloth nappy, have displayed a superior ability in containment of urine and feces, thereby reducing contamination and transmission of infection. Also disposable diapers contain Super Absorbent Material (SAM) that successfully reduces the incidence of nappy rash.

  6. Determining the extent of groundwater interference on the performance of infiltration trenches

    Science.gov (United States)

    Locatelli, Luca; Mark, Ole; Mikkelsen, Peter Steen; Arnbjerg-Nielsen, Karsten; Wong, Tony; Binning, Philip John

    2015-10-01

    Infiltration trenches are widely used in stormwater management, but their capacity decreases when installed in areas with shallow groundwater where infiltration is limited by groundwater drainage. Here the hydrological performance of single infiltration trenches in areas with shallow water tables is quantified in terms of their capability to reduce peak flow, peak volume and annual stormwater runoff volume. To simulate the long term hydrological performance of infiltration trenches two different models are employed. The models continuously simulate infiltration rates from infiltration trenches using a 19 year rainfall time series from Copenhagen as input. The annual and single event stormwater runoff reduction from infiltration trenches was determined for 9 different scenarios that covered different soil conditions and infiltration trench dimensions. Monte Carlo simulations were used in order to quantify the impact of parameter variability for each scenario. Statistical analysis of the continuous long term model simulations was used to quantify the hydrological performance of infiltration trenches. Results show that infiltration trenches are affected by groundwater when there is an unsaturated depth of less than 1.5-3 m in sandy loam, 6.5-8 m in silt loam and 11-12 m in silty clay loam. A correction factor that can be applied for infiltration trench design when there is a shallow groundwater table is presented. The analyses showed that below a certain value of unsaturated depth the dissipation capacity of the mound/groundwater becomes the dominant process determining the infiltration capacity from infiltration trenches. In these cases it is essential to consider the local groundwater conditions in the infiltration trench design process.

  7. The Incident in Trench A - Follow-up and Lessons

    CERN Multimedia

    Olga Beltramello; Peter Jenni

    An incident happened on 12th October during the dismounting of the HF truck platform in Trench A in the ATLAS cavern. Nobody was injured or in direct danger to be hurt, thanks in particular to the vigilance of the lifting operation crew. However, there is ample matter to reflect upon, and to recall safety measures applicable at any time in the cavern. What happened? During the lifting operation of a lateral platform from the orange HF Truck, used for example for the calorimeter assembly, one of the ~7 m long pillars fell on the access stairs into the ATLAS detector (sector 13). The standard operation to dismount the platform consisted in first unbolting the platform from its support pillars and removing it. Then, after securing a given pillar with the crane, this pillar is unbolted from the floor and removed. By mistake, this pillar was not bolted onto the floor, and fell when the platform was removed. Nobody was present in the trench during the lifting operation and the fall of the pillar. The contractor in...

  8. After Rasping by Phoenix in 'Snow White' Trench, Sol 60

    Science.gov (United States)

    2008-01-01

    NASA's Phoenix Mars Lander used the motorized rasp on the back of its robotic arm scoop during the mission's 60th Martian day, or sol, (July 26, 2008) to penetrate a hard layer at the bottom of a trench informally called 'Snow White.' This view, taken by the lander's Surface Stereo Imager and presented in approximately true color, shows the trench later the same sol. Most of the 16 holes left by a four-by-four array of rasp placements are visible in the central area of the image. A total 3 cubic centimeters, or about half a teaspoon, of material was collected in the scoop. Material in the scoop was collected both by the turning rasp, which threw material into the scoop through an opening at the back of the scoop, and by the scoop's front blade, which was run over the rasped area to pick up more shavings. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  9. High-power single-mode trench-assisted EDFA

    Science.gov (United States)

    Gaur, Ankita; Rastogi, Vipul

    2015-06-01

    A trench assisted, 0.15-NA, effective single mode leaky Erbium Doped Fiber Amplifier is proposed for high power applications. The segmented-core of the fiber enables to achieve 783 μm2 mode area which reduces nonlinearity and increases power handling capacity of the fiber. The leakage loss of the modes is controlled by annular core segments and low index trench in the cladding. The leakage loss of the LP11 mode is 10.49 dB/m and that of the fundamental mode is 0.017 dB/m at 1530 nm wavelength. We have injected 20 mW power into each mode and have calculated the gain for 26 m length of the fiber using 250 W pump at 980 nm wavelength. The signal power in the LP01 mode is amplified to 122 W and that in the LP11 mode drops down to 5.78×10-27 W. The low output signal power in LP11 mode ensures selective single mode amplification of fundamental mode. Selective single mode amplification confirms good beam quality at the output end.

  10. The Geoid: Effect of compensated topography and uncompensated oceanic trenches

    Science.gov (United States)

    Chase, C.G.; McNutt, Marcia K.

    1982-01-01

    The geoid is becoming increasingly important in interpretation of global tectonics. Most of the topography of the earth is isostatically compensated, so removal of its effect from the geoid is appropriate before tectonic modeling. The oceanic trenches, however, are dynamically depressed features and cannot be isostatically compensated in the classical way. Continental topography compensated at 35 km gives intracontinental geoidal undulations of up to 15 m over mountain ranges in a spherical harmonic expansion to order and degree 22. Oceanic topography compensated at 40 km, reasonable for the thermally supported long wavelengths, matches the +10 m difference between old continents and old oceans in a detailed NASA/GSFC geoid. Removing the assumed compensation for the oceanic trenches leaves negative anomalies of up to 9 m amplitude caused by their uncompensated mass deficit. This mass deficit acts as a partial "regional compensation" for the excess mass of the subducting slabs, and partly explains why geoidal (and gravity) anomalies over the cold slabs are less than thermal models predict.

  11. Additional electric field in real trench MOS barrier Schottky diode

    Science.gov (United States)

    Mamedov, R. K.; Aslanova, A. R.

    2016-04-01

    In real trench MOS barrier Schottky diode (TMBS diode) additional electric field (AEF) the whole is formed in the near contact region of the semiconductor and its propagation space is limited with the barrier metal and the metallic electrodes of MOS structures. Effective potential barrier height TMBS diode is formed via resulting electric field of superposition AEF and electric field of space charge region (SCR) semiconductor. The dependence of the resulting electric field intensity of the distance towards the inside the semiconductor is nonlinear and characterized by a peak at a certain distance from the interface. The thickness of the SCR in TMBS diode becomes equal to the trench depth. Force and energy parameters of the AEF, and thus resulting electric field in the SCR region, become dependent on the geometric design parameters TMBS diode. The forward I-V characteristic TMBS diode is described by the thermionic emission theory as in conventional flat Scottky diode, and in the reverse bias, current is virtually absent at initial voltage, appears abruptly at a certain critical voltage.

  12. Recommendations to the NRC for review criteria for alternative methods of low-level radioactive waste disposal: Task 2a, Below-ground vaults

    Energy Technology Data Exchange (ETDEWEB)

    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.

  13. Recommendations to the NRC for review criteria for alternative methods of low-level radioactive waste disposal: Task 2b: Earth-mounded concrete bunkers

    Energy Technology Data Exchange (ETDEWEB)

    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.

  14. Along-trench variations in the seismic structure of the incoming Pacific plate at the outer rise of the northern Japan Trench

    Science.gov (United States)

    Fujie, Gou; Kodaira, Shuichi; Sato, Takeshi; Takahashi, Tsutomu

    2016-01-01

    To investigate along-trench variations in the seismic structure of the incoming oceanic plate and their effect on water transportation by the oceanic plate, we conducted a wide-angle seismic survey of a trench-parallel transect 270 km long on the outer rise of the northern Japan Trench. The resulting seismic structure models show that the central part of the transect is characterized by rough topography, thick oceanic crust, low seismic velocities, and high Vp/Vs ratios, suggesting pervasive fracturing and high water content (hydration) there. These observations are consistent with the presence of an ancient fracture zone associated with ridge propagation. The trenchward extension of this fracture zone corresponds to an area of low interplate seismicity, low seismic velocities, and high Vp/Vs ratio around the depth of the subduction interface. Our results suggest that this ancient scar on the oceanic plate influences along-trench variations in interplate seismic coupling through its effect on water transportation.

  15. Clays in radioactive waste disposal

    OpenAIRE

    Delage, Pierre; Cui, Yu-Jun; Tang, Anh-Minh

    2010-01-01

    Clays and argillites are considered in some countries as possible host rocks for nuclear waste disposal at great depth. The use of compacted swelling clays as engineered barriers is also considered within the framework of the multi-barrier concept. In relation to these concepts, various research programs have been conducted to assess the thermo-hydro-mechanical properties of radioactive waste disposal at great depth. After introducing the concepts of waste isolation developed in Belgium, Fran...

  16. Silicon drift detectors with the drift field induced by pureB-coated trenches

    NARCIS (Netherlands)

    Nanver, Lis Karen; Kneževi´c, Tihomir; Suligoj, Tomislav

    2016-01-01

    Junction formation in deep trenches is proposed as a new means of creating a built-in drift field in silicon drift detectors (SDDs). The potential performance of this trenched drift detector (TDD) was investigated analytically and through simulations, and compared to simulations of conventional

  17. Influence of photoresist feature geometry on ECR plasma-etched HgCdTe trenches

    Science.gov (United States)

    Benson, J. David; Stoltz, Andrew J., Jr.; Kaleczyc, Andrew W.; Martinka, Mike; Almeida, Leo A.; Boyd, Phillip R.; Dinan, John H.

    2002-12-01

    Factors that affect width and aspect ratio in electron cyclotron resonance (ECR) etched HgCdTe trenches are investigated. The ECR etch bias and anisotropy are determined by photoresist feature erosion rate. The physical characteristics of the trenches are attributed to ECR plasma etch chemistry.

  18. Simple analytical expression for crosstalk estimation in homogeneous trench-assisted multi-core fibers

    DEFF Research Database (Denmark)

    Ye, Feihong; Tu, Jiajing; Saitoh, Kunimasa

    2014-01-01

    An analytical expression for the mode coupling coe cient in homogeneous trench-assisted multi-core fibers is derived, which has a sim- ple relationship with the one in normal step-index structures. The amount of inter-core crosstalk reduction (in dB) with trench-assisted structures compared...

  19. Contour trenching, a contribution to artificial recharge in a semi-arid area in Vietnam

    Science.gov (United States)

    Pramana, K. E. R.; Ertsen, M. W.; Uhlenbrook, S.; van de Giesen, N. C.

    2010-05-01

    The long term impact of contour trenching tends to be that more runoff turns into groundwater recharge. In 2008, the contribution of recharge at a contour trench plot was determined as potential and not quite visible. Recharge has not been confirmed, since groundwater level data at the contour trench plot were not available. For further study, 4 new observation wells were installed on 8 hectares contour trench plot to asses the impact of the trenches to the groundwater system. This investigation was conducted during a single rainy season in 2009, shortly after the construction of the new observation wells. The subsurface conditions seemed to be an important feature controlling recharge processes and groundwater flow. Well logs data indicated granite bedrock at about 25 m below loamy sand and weathered granite layer respectively. The groundwater measurements are showing almost constant and fluctuated groundwater level between 1 to 15 meters deep below the trenches. More important is that data are showing a rising trend because of the infiltration of ponding water in the trenches. Additionally, water logging could be found remaining in weeks after rainfall events at the most downhill of the contour trench plot. Annual rainfall reached 1303 mm, suggesting a rarely wet year. After 4 heavy rainfall events, runoff from uphill and outside the contour trench plot randomly filled up the trenches, yielded to roughly 4 times filling up the volume of the trenches. Ponding water infiltrated further in different temporal scale. Whilst at the same time, erosion occurred at the uphill area, bringing along fine sediment towards the trenches. It eventually creates a sediment layer at the bottom the trenches which in accordance reduces the infiltration capacity and thus increases the time of ponding of water. MODHMS from HydroGeologic Inc. (a fully coupled surface water, unsaturated zone and groundwater model) was used to simulate the hydrological condition and measured groundwater

  20. Navigation Tracklines of the Puerto Rico Trench Cruise 03008 (NOAA 0303) February 18 to March 7, 2003 (nav2003)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Puerto Rico trench is a tectonic plate boundary where the North American plate slides by and descends under the Caribbean plate. Although much of the trench lies...

  1. Navigation Tracklines of the Puerto Rico Trench Cruise 02051 (NOAA 0208) September 24 to September 30, 2002 (nav2002)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Puerto Rico trench is a tectonic plate boundary where the North American plate slides by and descends under the Caribbean plate. Although much of the trench lies...

  2. Improved model-based infrared reflectrometry for measuring deep trench structures.

    Science.gov (United States)

    Zhang, Chuanwei; Liu, Shiyuan; Shi, Tielin; Tang, Zirong

    2009-11-01

    Model-based infrared reflectrometry (MBIR) has been introduced recently for characterization of high-aspect-ratio deep trench structures in microelectronics. The success of this technique relies heavily on accurate modeling of trench structures and fast extraction of trench parameters. In this paper, we propose a modeling method named corrected effective medium approximation (CEMA) for accurate and fast reflectivity calculation of deep trench structures. We also develop a method combining an artificial neural network (ANN) and a Levenberg-Marquardt (LM) algorithm for robust and fast extraction of geometric parameters from the measured reflectance spectrum. The simulation and experimental work conducted on typical deep trench structures has verified the proposed methods and demonstrated that the improved MBIR metrology achieves highly accurate measurement results as well as fast computation speed.

  3. 20-μm deep trench isolation process characterization for linear bipolar ICs

    Science.gov (United States)

    Dyer, Terry; Doohan, Ian J.; Fallon, Martin; McAlpine, Dave; Aitkenhead, Adam; McGinty, Jim; Taylor, M.; Gravelle, Philip; Schouten, A.; Bryce, M.

    2001-04-01

    The use of junction isolation in linear bipolar ICs substantially consumes silicon area. The replacement of junction isolation with trench isolation has the potential to significantly reduce device area while maintaining high voltage operation. Deep trench isolation has been implemented on a conventional non- complementary 40V (NPN BVceo) linear IC process. A fully functional lower power operational amplifier has been fabricated as a technology driver. Device characterization shows that transistor leakage currents (Iceo) and leakage between trench tubs can be made comparable with junction isolated devices. The NPN buried layer can successfully be butted against the trench sidewall without device degradation, although this is currently not possible with the NPN base. An NPN device shrink of 3X has been achieved and further development is underway to increase this towards the 4X level, where the base diffusion front touches the trench sidewall.

  4. Interim-status groundwater monitoring plan for the 216-B-63 trench. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    Sweeney, M.D.

    1995-06-13

    This document outlines the groundwater monitoring plan for interim-status detection-level monitoring of the 216-B-63 Trench. This is a revision of the initial groundwater monitoring plan prepared for Westinghouse Hanford Company (WHC) by Bjornstad and Dudziak (1989). The 216-B-63 Trench, located at the Hanford Site in south-central Washington State, is an open, unlined, earthern trench approximately 1.2 m (4 ft) wide at the bottom, 427 m (1400 ft) long, and 3 m (10 ft) deep that received wastewater containing hazardous waste and radioactive materials from B Plant, located in the 200 East Area. Liquid effluent discharge to the 216-B-63 Trench began in March 1970 and ceased in February 1992. The trench is now managed by Waste Tank Operations.

  5. Determining the extent of groundwater interference on the performance of infiltration trenches

    DEFF Research Database (Denmark)

    Locatelli, Luca; Mark, Ole; Mikkelsen, Peter Steen;

    2015-01-01

    depth of less than 1.5-3. m in sandy loam, 6.5-8. m in silt loam and 11-12. m in silty clay loam. A correction factor that can be applied for infiltration trench design when there is a shallow groundwater table is presented. The analyses showed that below a certain value of unsaturated depth...... the dissipation capacity of the mound/groundwater becomes the dominant process determining the infiltration capacity from infiltration trenches. In these cases it is essential to consider the local groundwater conditions in the infiltration trench design process.......Infiltration trenches are widely used in stormwater management, but their capacity decreases when installed in areas with shallow groundwater where infiltration is limited by groundwater drainage. Here the hydrological performance of single infiltration trenches in areas with shallow water tables...

  6. '05 Safety Case in a Potential HLW Disposal in ROK for Better Communication among Stakeholders

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Y.S. [Korea Atomic Energy Research Inst., Daejeon (Korea)

    2006-09-15

    The national effort to secure a site to dispose of LLW In Korea has been successfully completed when Gyeongjoo was finally selected through its local referendum on Nov 2 in 2005. The focus has been shifted to the future of spent nuclear fuels generated by 20 reactors in four nuclear complexes. Korea has a solid plan to raise its nuclear share, with 28 reactors in operation, in the electricity generation to 46.7% by 2017.The total amount of spent nuclear fuel from these reactors will be 36,000 MT. To dispose of 36,000 MT, at least a four square kilometer underground layer is required. The characteristics of Korean disposal conditions are rather unique. Korea has a mixture of CANDU and PWR whose inventories and decay heats are quits different. The spent nuclear fuel is assumed to be emplaced into stainless steel containers filled with cast iron. Calcium bentonite is used as a buffer material between a waste container and a surrounding rock. Radionuclides passing through barriers will eventually reach the biosphere. Two pathways are identified as major ones; one following the stream of ground and surface waters to the ground surface, a river and a marine environment, the other intersecting a small well whose extracted water is consumed by local residents. To safely dispose of spent nuclear fuels KAERI has developed the Korean Reference Disposal System (KRS). To assess the long term post closure radiological safety, KAERI has developed the following products: (1) The KAERI FEP Encyclopedia; (2) Reference and alternative scenarios in association with the corresponding rock engineering system matrices, assessment method context and flow charts; (3) Assessment codes MASCOT-K and MDPSA; (4) PAID, the input datahabe for total system performance assessment; (5) Safety assessment on two reference and other selected scenarios; (6) Korean biosphere modeling. and (7) Quality assurance systems in association with the CYPRUS, the cyber RandD platform system; and (8) The flow

  7. Early History of Island Arcs - Evidence from the Mariana Trench

    Science.gov (United States)

    Hawkins, J. W.

    2004-12-01

    Among the many problems concerning the initiation and early history of island arcs is the question - what underlies arc plutonic and volcanic series ? Conventional wisdom is that arcs are built on older ocean crust. Their deep roots should include high-Mg eruptions, crystal cumulates complementry to higher-level differentiated lavas, plutonic rocks compositionally equivalent to lavas, and depleted mantle residue complementary to extracted arc magmas. If built on older ocean crust, the "roots" should overlie seafloor sediments, pillows, dikes, etc. (i.e., ophiolites). Probable exposures of deep roots of arcs are rare; exposures such as Tonsina Complex, Alaska and Zambales Range, Luzon are notable for a lack of evidence for subjacent ocean crust. The Zambales shows unmistakeable evidence for continuity from depleted harzburgite/dunite to a thick layered cumulate series of wehrlite,dunite, pyroxenite; these are overlain by norite, gabbro and arc tholeiite basalt. Much of the cumulate series and norite-gabbro has blasto-mylonite texture. These petrologic features suggest upwelling of parental peridotite mantle into a realm of oceanic lithosphere extension. The nascent arc has replaced former ocean crust rather than being built on it. The extensional regime, owing to subduction and seaward trench roll-back, has driven opening of back arc basins, caused forearc rifting, and provided a rift setting for initiation of arc magmatism. Rocks dredged from the Mariana Trench (14 to 18 N) from depths of 9000 to 3000 m, display evidence for near-solidus penetrative deformation that developed higher amphibolite facies mylonites and blasto-mylonites. Rocks include depleted peridotite, pyroxenite, wehrlite, cumulate amphibolite, norite/gabbro, tonalite. High-T metamorphism is shown by equilibrium assemblages of labradorite-bytownite, AL-hornblende, ortho- and clino- pyroxene. Highly deformed homogeneous calcic plagioclase has cross-cutting veins of xenoblastic plagioclase and rare

  8. Geophysical investigation using resistivity and GPR methods: a case study of a lubricant oil waste disposal area in the city of Ribeirão Preto, São Paulo, Brazil

    Science.gov (United States)

    Lago, Alexandre Lisboa; Elis, Vagner Roberto; Borges, Welitom Rodrigues; Penner, Giovanni Chaves

    2009-07-01

    Geophysics has been shown to be effective in identifying areas contaminated by waste disposal, contributing to the greater efficiency of soundings programs and the installation of monitoring wells. In the study area, four trenches were constructed with a total volume of about 25,000 m3. They were almost totally filled with re-refined lubricating oil waste for approximately 25 years. No protection liners were used in the bottoms and laterals of the disposal trenches. The purpose of this work is to evaluate the potential of the resistivity and ground penetrating radar (GPR) methods in characterizing the contamination of this lubricant oil waste disposal area in Ribeirão Preto, SP, situated on the geological domain of the basalt spills of the Serra Geral Formation and the sandstones of the Botucatu Formation. Geophysical results were shown in 2D profiles. The geophysical methods used enabled the identification of geophysical anomalies, which characterized the contamination produced by the trenches filled with lubricant oil waste. Conductive anomalies (smaller than 185 Ωm) immediately below the trenches suggest the action of bacteria in the hydrocarbons, as has been observed in several sites contaminated by hydrocarbons in previously reported cases in the literature. It was also possible to define the geometry of the trenches, as evidenced by the GPR method. Direct sampling (chemical analysis of the soil and the water in the monitoring well) confirmed the contamination. In the soil analysis, low concentrations of several polycyclic aromatic hydrocarbons (PAHs) were found, mainly naphthalene and phenanthrene. In the water samples, an analysis verified contamination of the groundwater by lead (Pb). The geophysical methods used in the investigation provided an excellent tool for environmental characterization in this study of a lubricant oil waste disposal area, and could be applied in the study of similar areas.

  9. Conceptual designs of near surface disposal facility for radioactive waste arising from the facilities using radioisotopes and research facilities for nuclear energy development and utilization

    Energy Technology Data Exchange (ETDEWEB)

    Sakai, Akihiro; Yoshimori, Michiro; Okoshi, Minoru; Yamamoto, Tadatoshi; Abe, Masayoshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2001-03-01

    Various kinds of radioactive waste is generating from the utilization of radioisotopes in the field of science, technology, etc. and the utilization and development of nuclear energy. In order to promote the utilization of radionuclides and the research activities, it is necessary to treat and dispose of radioactive waste safely and economically. Japan Nuclear Cycle Development Institute (JNC), Japan Radioisotope Association (JRIA) and Japan Atomic Energy Research Institute (JAERI), which are the major waste generators in Japan in these fields, are promoting the technical investigations for treatment and disposal of the radioactive waste co-operately. Conceptual design of disposal facility is necessary to demonstrate the feasibility of waste disposal business and to determine the some conditions such as the area size of the disposal facility. Three institutes share the works to design disposal facility. Based on our research activities and experiences of waste disposal, JAERI implemented the designing of near surface disposal facilities, namely, simple earthen trench and concrete vaults. The designing was performed based on the following three assumed site conditions to cover the future site conditions: (1) Case 1 - Inland area with low groundwater level, (2) Case 2 - Inland area with high groundwater level, (3) Case 3 - Coastal area. The estimation of construction costs and the safety analysis were also performed based on the designing of facilities. The safety assessment results show that the safety for concrete vault type repository is ensured by adding low permeability soil layer, i.e. mixture of soil and bentonite, surrounding the vaults not depending on the site conditions. The safety assessment results for simple earthen trench also show that their safety is ensured not depending on the site conditions, if they are constructed above groundwater levels. The construction costs largely depend on the depth for excavation to build the repositories. (author)

  10. Conceptual designs of near surface disposal facility for radioactive waste arising from the facilities using radioisotopes and research facilities for nuclear energy development and utilization

    Energy Technology Data Exchange (ETDEWEB)

    Sakai, Akihiro; Yoshimori, Michiro; Okoshi, Minoru; Yamamoto, Tadatoshi; Abe, Masayoshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2001-03-01

    Various kinds of radioactive waste is generating from the utilization of radioisotopes in the field of science, technology, etc. and the utilization and development of nuclear energy. In order to promote the utilization of radionuclides and the research activities, it is necessary to treat and dispose of radioactive waste safely and economically. Japan Nuclear Cycle Development Institute (JNC), Japan Radioisotope Association (JRIA) and Japan Atomic Energy Research Institute (JAERI), which are the major waste generators in Japan in these fields, are promoting the technical investigations for treatment and disposal of the radioactive waste co-operately. Conceptual design of disposal facility is necessary to demonstrate the feasibility of waste disposal business and to determine the some conditions such as the area size of the disposal facility. Three institutes share the works to design disposal facility. Based on our research activities and experiences of waste disposal, JAERI implemented the designing of near surface disposal facilities, namely, simple earthen trench and concrete vaults. The designing was performed based on the following three assumed site conditions to cover the future site conditions: (1) Case 1 - Inland area with low groundwater level, (2) Case 2 - Inland area with high groundwater level, (3) Case 3 - Coastal area. The estimation of construction costs and the safety analysis were also performed based on the designing of facilities. The safety assessment results show that the safety for concrete vault type repository is ensured by adding low permeability soil layer, i.e. mixture of soil and bentonite, surrounding the vaults not depending on the site conditions. The safety assessment results for simple earthen trench also show that their safety is ensured not depending on the site conditions, if they are constructed above groundwater levels. The construction costs largely depend on the depth for excavation to build the repositories. (author)

  11. Tank Waste Disposal Program redefinition

    Energy Technology Data Exchange (ETDEWEB)

    Grygiel, M.L.; Augustine, C.A.; Cahill, M.A.; Garfield, J.S.; Johnson, M.E.; Kupfer, M.J.; Meyer, G.A.; Roecker, J.H. [Westinghouse Hanford Co., Richland, WA (United States); Holton, L.K.; Hunter, V.L.; Triplett, M.B. [Pacific Northwest Lab., Richland, WA (United States)

    1991-10-01

    The record of decision (ROD) (DOE 1988) on the Final Environmental Impact Statement, Hanford Defense High-Level, Transuranic and Tank Wastes, Hanford Site, Richland Washington identifies the method for disposal of double-shell tank waste and cesium and strontium capsules at the Hanford Site. The ROD also identifies the need for additional evaluations before a final decision is made on the disposal of single-shell tank waste. This document presents the results of systematic evaluation of the present technical circumstances, alternatives, and regulatory requirements in light of the values of the leaders and constitutents of the program. It recommends a three-phased approach for disposing of tank wastes. This approach allows mature technologies to be applied to the treatment of well-understood waste forms in the near term, while providing time for the development and deployment of successively more advanced pretreatment technologies. The advanced technologies will accelerate disposal by reducing the volume of waste to be vitrified. This document also recommends integration of the double-and single-shell tank waste disposal programs, provides a target schedule for implementation of the selected approach, and describes the essential elements of a program to be baselined in 1992.

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

    Energy Technology Data Exchange (ETDEWEB)

    Pick, Thomas Stefan; Bluth, Joachim; Lauenstein, Christof; Markhoefer, Joerg [Niedersaechsisches Ministerium fuer Umwelt und Klimaschutz, Ministry for Environment and Climate Protection of Lower Saxony (Germany)

    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

  13. Special Analysis of Transuranic Waste in Trench T04C at the Area 5 Radioactive Waste Management Site, Nevada Test Site, Nye County, Nevada, Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    Greg Shott, Vefa Yucel, Lloyd Desotell

    2008-05-01

    This Special Analysis (SA) was prepared to assess the potential impact of inadvertent disposal of a limited quantity of transuranic (TRU) waste in classified Trench 4 (T04C) within the Area 5 Radioactive Waste Management Site (RWMS) at the Nevada Test Site (NTS). The Area 5 RWMS is a low-level radioactive waste disposal site in northern Frenchman Flat on the Nevada Test Site (NTS). The Area 5 RWMS is regulated by the U.S. Department of Energy (DOE) under DOE Order 435.1 and DOE Manual (DOE M) 435.1-1. The primary objective of the SA is to evaluate if inadvertent disposal of limited quantities of TRU waste in a shallow land burial trench at the Area 5 RWMS is in compliance with the existing, approved Disposal Authorization Statement (DAS) issued under DOE M 435.1-1. In addition, supplemental analyses are performed to determine if there is reasonable assurance that the requirements of Title 40, Code of Federal Regulations (CFR), Part 191, Environmental Radiation Protection Standards for Management and Disposal of Spent Nuclear Fuel, High-Level, and Transuranic Radioactive Wastes, can be met. The 40 CFR 191 analyses provide supplemental information regarding the risk to human health and the environment of leaving the TRU waste in T04C. In 1989, waste management personnel reviewing classified materials records discovered that classified materials buried in trench T04C at the Area 5 RWMS contained TRU waste. Subsequent investigations determined that a total of 102 55-gallon drums of TRU waste from Rocky Flats were buried in trench T04C in 1986. The disposal was inadvertent because unclassified records accompanying the shipment indicated that the waste was low-level. The exact location of the TRU waste in T04C was not recorded and is currently unknown. Under DOE M 435.1-1, Chapter IV, Section P.5, low-level waste disposal facilities must obtain a DAS. The DAS specifies conditions that must be met to operate within the radioactive waste management basis, consisting of a

  14. Depleted uranium disposal options evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Hertzler, T.J.; Nishimoto, D.D.; Otis, M.D. [Science Applications International Corp., Idaho Falls, ID (United States). Waste Management Technology Div.

    1994-05-01

    The Department of Energy (DOE), Office of Environmental Restoration and Waste Management, has chartered a study to evaluate alternative management strategies for depleted uranium (DU) currently stored throughout the DOE complex. Historically, DU has been maintained as a strategic resource because of uses for DU metal and potential uses for further enrichment or for uranium oxide as breeder reactor blanket fuel. This study has focused on evaluating the disposal options for DU if it were considered a waste. This report is in no way declaring these DU reserves a ``waste,`` but is intended to provide baseline data for comparison with other management options for use of DU. To PICS considered in this report include: Retrievable disposal; permanent disposal; health hazards; radiation toxicity and chemical toxicity.

  15. The effect of a power-law mantle viscosity on trench retreat rate

    Science.gov (United States)

    Holt, Adam F.; Becker, Thorsten W.

    2017-01-01

    The subduction of lithospheric plates is partitioned between subducting plate motion and lateral slab migration (i.e. trench retreat and advance). We use 3-D, dynamic models of subduction to address the role of a power-law mantle viscosity on subduction dynamics and, in particular, rates of trench retreat. For all numerical models tested, we find that a power-law rheology results in reduced rates of trench retreat, and elevated slab dip angles, relative to the equivalent isoviscous mantle model. We analyse the asthenospheric pressure distribution and the style of mantle flow, which exhibits only limited variability as a function of mantle rheology, in order to compute estimates of the mantle forces associated with subduction. The inclusion of a power-law rheology reduces the mantle shear force (which resists subducting plate motion) to a greater degree than it reduces the dynamic pressure gradient across the slab (which resists trench retreat). Therefore, the inclusion of a power-law mantle rheology favours a shift towards a subduction mode with a reduced trench retreat component, typically a relative reduction of order 25 per cent in our 3-D models. We suggest that this mechanism may be of importance for reducing the high trench retreat rates observed in many previous models to levels more in line with the average subduction partitioning observed on Earth at present (i.e. trench velocity ≤ plate velocity), for most absolute plate motion reference frames.

  16. Long-term safety assessment of trench-type surface repository at Chernobyl, Ukraine - computer model and comparison with results from simplified models

    Energy Technology Data Exchange (ETDEWEB)

    Haverkamp, B.; Krone, J. [DBE TECHNOLOGY GmbH, Peine (Germany); Shybetskyi, I. [Radioenvironmental Centre at Presidium of National Academy of Sciences of Ukraine, Kiev (Ukraine)

    2013-07-01

    The Radioactive Waste Disposal Facility (RWDF) Buryakovka was constructed in 1986 as part of the intervention measures after the accident at Chernobyl NPP (ChNPP). Today, the surface repository for solid low and intermediate level waste (LILW) is still being operated but its maximum capacity is nearly reached. Long-existing plans for increasing the capacity of the facility shall be implemented in the framework of the European Commission INSC Programme (Instrument for Nuclear Safety Co-operation). Within the first phase of this project, DBE Technology GmbH prepared a safety analysis report of the facility in its current state (SAR) and a preliminary safety analysis report (PSAR) for a future extended facility based on the planned enlargement. In addition to a detailed mathematical model, also simplified models have been developed to verify results of the former one and enhance confidence in the results. Comparison of the results show that - depending on the boundary conditions - simplifications like modeling the multi trench repository as one generic trench might have very limited influence on the overall results compared to the general uncertainties associated with respective long-term calculations. In addition to their value in regard to verification of more complex models which is important to increase confidence in the overall results, such simplified models can also offer the possibility to carry out time consuming calculations like probabilistic calculations or detailed sensitivity analysis in an economic manner. (authors)

  17. Efficiency Enhancement of Nanoporous Silicon/Polycrystalline-Silicon Solar Cells by Application of Trenched Electrodes

    OpenAIRE

    Kuen-Hsien Wu; Chia-Chun Tang

    2014-01-01

    Trenched electrodes were proposed to enhance the short-circuit current and conversion efficiency of polycrystalline-silicon (poly-Si) solar cells with nanoporous silicon (NPS) surface layers. NPS films that served as textured surface layers were firstly prepared on heavily doped p+-type (100) poly-Si wafers by anodic etching process. Interdigitated trenches were formed in the NPS layers by a reactive-ion-etch (RIE) process and Cr/Al double-layered metal was then deposited to fill the trenches...

  18. Light extinction and scattering from individual and arrayed high-aspect-ratio trenches in metal

    DEFF Research Database (Denmark)

    Roberts, Alexander; Søndergaard, Thomas; Chirumamilla, Manohar

    2016-01-01

    for a two-dimensional scatterer. We construct a simple resonator model which predicts the wavelength-dependent extinction, scattering, and absorption cross section of the trench and compare the model findings with full numerical simulations. Both extinction and scattering cross sections are mainly...... determined by the wavelength and can reach highly supergeometric values. At wavelengths where the metal exhibits near perfect electrical conductor behavior, such trenches lend themselves to be used as self-normalizing scatterers, as their scattering cross section is independent of their geometry and depend...... and two-photon luminescence that the resonant behavior of the vertical trenches is preserved....

  19. Evaluation of two stormwater infiltration trenches in central Copenhagen after 15 years of operation

    DEFF Research Database (Denmark)

    Bergman, Maria Kerstin; Hedegaard, Mathilde Jørgensen; Petersen, Mette Fjendbo;

    2011-01-01

    Two stormwater infiltration trenches were installed in 1993 in an area in central Copenhagen. The system was monitored continuously for almost three years after establishment, and a small reduction in performance over that time, possibly due to clogging, was noted. A new study was conducted in 2009...... to see whether the reduction in performance has continued and to determine how the system performs today. Water levels in the trenches were monitored for almost 4 months, and from this period seven events were selected to analyse the infiltration rate. A comparison with similar analyses on storm...... factors to consider when implementing stormwater infiltration trenches. © IWA Publishing 2011....

  20. Cathodoluminescence studies of GaAs nano-wires grown on shallow-trench-patterned Si

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ling; Fan, Wen-Chung; Ku, Jui-Tai; Chang, Wen-Hao; Chen, Wei-Kuo; Chou, Wu-Ching [Department of Electrophysics, National Chiao Tung University, Hsinchu 300, Taiwan (China); Ko, Chih-Hsin; Wu, Cheng-Hsien; Lin, You-Ru; Wann, Clement H [Taiwan Semiconductor Manufacturing Co., Ltd, Hsinchu 300, Taiwan (China); Hsu, Chao-Wei; Chen, Yung-Feng; Su, Yan-Kuin, E-mail: acceptor.ep89g@nctu.edu.tw, E-mail: wuchingchou@mail.nctu.edu.tw [Institute of Microelectronics and Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan 701, Taiwan (China)

    2010-11-19

    The optical properties of GaAs nano-wires grown on shallow-trench-patterned Si(001) substrates were investigated by cathodoluminescence. The results showed that when the trench width ranges from 80 to 100 nm, the emission efficiency of GaAs can be enhanced and is stronger than that of a homogeneously grown epilayer. The suppression of non-radiative centers is attributed to the trapping of both threading dislocations and planar defects at the trench sidewalls. This approach demonstrates the feasibility of growing nano-scaled GaAs-based optoelectronic devices on Si substrates.

  1. Scoping survey of perceived concerns, issues, and problems for near-surface disposal of FUSRAP waste

    Energy Technology Data Exchange (ETDEWEB)

    Robinson, J.E.; Gilbert, T.L.

    1982-12-01

    This report is a scoping summary of concerns, issues, and perceived problems for near-surface disposal of radioactive waste, based on a survey of the current literature. Near-surface disposal means land burial in or within 15 to 20 m of the earth's surface. It includes shallow land burial (burial in trenches, typically about 6 m deep with a 2-m cap and cover) and some intermediate-depth land burial (e.g., trenches and cap similar to shallow land burial, but placed below 10 to 15 m of clean soil). Proposed solutions to anticipated problems also are discussed. The purpose of the report is to provide a better basis for identifying and evaluating the environmental impacts and related factors that must be analyzed and compared in assessing candidate near-surface disposal sites for FUSRAP waste. FUSRAP wastes are of diverse types, and their classification for regulatory purposes is not yet fixed. Most of it may be characterized as low-activity bulk solid waste, and is similar to mill tailings, but with somewhat lower average specific activity. It may also qualify as Class A segregated waste under the proposed 10 CFR 61 rules, but the parent radionuclides of concern in FUSRAP (primarily U-238 and Th-232) have longer half-lives than do the radionuclides of concern in most low-level waste. Most of the references reviewed deal with low-level waste or mill tailings, since there is as yet very little literature in the public domain on FUSRAP per se.

  2. A mathematical model for the performance assessment of engineering barriers of a typical near surface radioactive waste disposal facility

    Energy Technology Data Exchange (ETDEWEB)

    Antonio, Raphaela N.; Rotunno Filho, Otto C. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia. Lab. de Hidrologia e Estudos do Meio Ambiente]. E-mail: otto@hidro.ufrj.br; Ruperti Junior, Nerbe J.; Lavalle Filho, Paulo F. Heilbron [Comissao Nacional de Energia Nuclear (CNEN), Rio de Janeiro, RJ (Brazil)]. E-mail: nruperti@cnen.gov.br

    2005-07-01

    This work proposes a mathematical model for the performance assessment of a typical radioactive waste disposal facility based on the consideration of a multiple barrier concept. The Generalized Integral Transform Technique is employed to solve the Advection-Dispersion mass transfer equation under the assumption of saturated one-dimensional flow, to obtain solute concentrations at given times and locations within the medium. A test-case is chosen in order to illustrate the performance assessment of several configurations of a multi barrier system adopted for the containment of sand contaminated with Ra-226 within a trench. (author)

  3. General Instructions for Disposable Respirators

    Centers for Disease Control (CDC) Podcasts

    2009-04-09

    This podcast, intended for the general public, demonstrates how to put on and take off disposable respirators that are to be used in areas affected by the influenza outbreak.  Created: 4/9/2009 by CDC, National Institute for Occupational Safety and Health (NIOSH).   Date Released: 4/29/2009.

  4. Disposables: saving by throwing away.

    Science.gov (United States)

    Wilton, G

    1980-07-18

    The demand for health care facilities and services will remain insatiable, concludes a report by Frost and Sullivan due to be published shortly. The report on trends in the European clinical soft goods market says growth is guaranteed but that the market penetration of disposables is not.

  5. Ocean Disposal of Dredged Material

    Science.gov (United States)

    Permits and authorizations for the ocean dumping of dredged material is issued by U.S. Army Corps of Engineers. Information is provided about where to dispose dredged material and the process for obtaining an ocean dumping permit for dredged material.

  6. Vadose Zone Contaminant Fate and Transport Analysis for the 216-B-26 Trench

    Energy Technology Data Exchange (ETDEWEB)

    Ward, Andy L.; Gee, Glendon W.; Zhang, Z. F.; Keller, Jason M.

    2004-10-14

    The BC Cribs and Trenches, part of the 200 TW 1 OU waste sites, received about 30 Mgal of scavenged tank waste, with possibly the largest inventory of 99Tc ever disposed to the soil at Hanford and site remediation is being accelerated. The purpose of this work was to develop a conceptual model for contaminant fate and transport at the 216-B-26 Trench site to support identification and development and evaluation of remediation alternatives. Large concentrations of 99Tc high above the water table implicated stratigraphy in the control of the downward migration. The current conceptual model accounts for small-scale stratigraphy; site-specific changes soil properties; tilted layers; and lateral spreading. It assumes the layers are spatially continuous causing water and solutes to move laterally across the boundary if conditions permit. Water influx at the surface is assumed to be steady. Model parameters were generated with pedotransfer functions; these were coupled high resolution neutron moisture logs that provided information on the underlying heterogeneity on a scale of 3 inches. Two approaches were used to evaluate the impact of remedial options on transport. In the first, a 1-D convolution solution to the convective-dispersive equation was used, assuming steady flow. This model was used to predict future movement of the existing plume using the mean and depth dependent moisture content. In the second approach, the STOMP model was used to first predict the current plume distribution followed by its future migration. Redistribution of the 99Tc plume was simulated for the no-action alternative and on-site capping. Hypothetical caps limiting recharge to 1.0, 0.5, and 0.1 mm yr-1 were considered and assumed not to degrade in the long term. Results show that arrival time of the MCLs, the peak arrival time, and the arrival time of the center of mass increased with decreasing recharge rate. The 1-D convolution model is easy to apply and can easily accommodate initial

  7. Oceanographic cruise Indian Ocean and Java Trench June 1969 (NODC Accession 7100908)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This report contains oceanographic data which was obtained aboard H.M.A.S DIAMANTINA during an oceanographic cruise in the Java Trench and the Indian Ocean during...

  8. Oceanographic cruise: Coral Sea, Arafura Sea, and Java Trench, April - May 1969 (NODC Accession 7100914)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This report contains oceanographic data which was obtained aboard HMAS DIAMANTINA during an oceanographic cruise in the Coral Sea, Arafura Sea, and Java Trench...

  9. Complex morphology of subducted lithosphere in the mantle beneath the Tonga trench

    NARCIS (Netherlands)

    Hilst, R.D. van der

    1995-01-01

    At the Tonga trench, old Pacific sea floor subducts at a rapid rate below the Indo-Australia plate, generating most of the world's deep earthquakes and producing a deep slab of former oceanic lithosphere.

  10. Large fault slip peaking at trench in the 2011 Tohoku-oki earthquake

    Science.gov (United States)

    Sun, Tianhaozhe; Wang, Kelin; Fujiwara, Toshiya; Kodaira, Shuichi; He, Jiangheng

    2017-01-01

    During the 2011 magnitude 9 Tohoku-oki earthquake, very large slip occurred on the shallowest part of the subduction megathrust. Quantitative information on the shallow slip is of critical importance to distinguishing between different rupture mechanics and understanding the generation of the ensuing devastating tsunami. However, the magnitude and distribution of the shallow slip are essentially unknown due primarily to the lack of near-trench constraints, as demonstrated by a compilation of 45 rupture models derived from a large range of data sets. To quantify the shallow slip, here we model high-resolution bathymetry differences before and after the earthquake across the trench axis. The slip is determined to be about 62 m over the most near-trench 40 km of the fault with a gentle increase towards the trench. This slip distribution indicates that dramatic net weakening or strengthening of the shallow fault did not occur during the Tohoku-oki earthquake.

  11. Comparison between infaunal communities of the deep floor and edge of the Tonga Trench

    DEFF Research Database (Denmark)

    Leduc, Daniel; Rowden, Ashley A.; Glud, Ronnie N.

    2016-01-01

    factors. In this study, we describe and compare the abundance, biomass, vertical distribution in the sediment, diversity, and community structure of nematodes and other infauna in sediments from the Horizon Deep (similar to 10 800 m) in the Tonga Trench and a site on the edge of the trench (similar...... to 6250 m). Mean nematode abundance was six times greater at the Horizon Deep site (387 ind. 10 cm(-2)) than at the trench edge site (65 ind. 10 cm(-2)). A similar pattern was observed for biomass (15 vs 2 mu gDW 10 cm(-2), respectively), which likely resulted from elevated organic matter supply...... at the Horizon Deep site. There was no significant difference in nematode species richness between the two sites, but diversity measured using rarefaction was significantly greater at the trench edge site than at the Horizon Deep site [ES(20); 13.8 vs 7.8]. Dominance was much more pronounced in the Horizon Deep...

  12. 48 CFR 245.603 - Disposal methods.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Disposal methods. 245.603 Section 245.603 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS SYSTEM, DEPARTMENT... Contractor Inventory 245.603 Disposal methods....

  13. Trench migration, net rotation and slab mantle coupling

    Science.gov (United States)

    Funiciello, F.; Faccenna, C.; Heuret, A.; Lallemand, S.; Di Giuseppe, E.; Becker, T. W.

    2008-07-01

    Laboratory models have been conducted to improve our understanding of the role that the resistance of the slab to bending and its coupling to the ambient mantle play in subduction dynamics over geological time scales. Our models are set up with a viscous plate of silicone (lithosphere) subducting under negative buoyancy in a viscous layer of glucose syrup (mantle). For our study, the lithosphere/upper mantle viscosity contrast has been systematically varied, from ~ 10 to ~ 10 5 in order to explore the parameter space between weak and strong slab dynamics. We found that subduction is characterized by a retreating mode for viscosity ratios > 10 4, by the coexistence of a retreating mode and an advancing mode for viscosity ratios between ~ 10 4 and ~ 10 2, and quasi-stationary, Rayleigh-Taylor like behaviour for ratios < 10 2. By combining our experimental results and kinematic data from current subduction zones in four reference frames which differ in the amount of net rotation, we infer that a lithosphere/upper mantle viscosity contrast of 150-500 is necessary to obtain realistic trench/subducting plate velocity ratios as well as the variability of subduction styles observed in nature.

  14. Mode mixing in asymmetric double trench photonic crystal waveguides

    CERN Document Server

    Vlasov, Y A; McNab, S J; Vlasov, Yu. A.

    2003-01-01

    e investigate both experimentally and theoretically the waveguiding properties of a novel double trench waveguide where a conventional single-mode strip waveguide is embedded in a two dimensional photonic crystal (PhC) slab formed in silicon on insulator (SOI) wafers. We demonstrate that the bandwidth for relatively low-loss (50dB/cm) waveguiding is significantly expanded to 250nm covering almost all the photonic band gap owing to nearly linear dispersion of the TE-like waveguiding mode. The flat transmission spectrum however is interrupted by numerous narrow stop bands. We found that these stop bands can be attributed to anti-crossing between TE-like (positive parity) and TM-like (negative parity) modes. This effect is a direct result of the strong asymmetry of the waveguides that have an upper cladding of air and lower cladding of oxide. To our knowledge this is the first demonstration of the effects of cladding asymmetry on the transmission characteristics of the PhC slab waveguides.

  15. The importance of trenching in paleoseismic studies in Venezuela: brief historical summary

    Science.gov (United States)

    Murria, J.

    2009-04-01

    Paleoseismic studies have proved to be a powerful tool in seismic hazards assessment by he contributing to asses the seismogenic potential of a given fault by expanding the time window o seismic activity beyond the limits of historical and instrumental seismicity. Trenching has been an essential tool for paleoseismic studies in Venezuela. The first paleoseismic trenching project in Venezuela goes back to 1968 when Compania Shell de Venezuela retained the services of Woodward Clyde and Associates,(WCA), USA to asses the seismic integrity of the earthen dikes of Costa Oriental of Lake Maracaibo Protection System (COLM) in western Venezuela. The study was carried out under the general coordination of this author. An important part of this project included a seismology and seismic geology study under the direction of Geologist L.S. Cluff. This was the first ever study undertaken in Venezuela and included two excavations across the Oca Fault north of the city of Maracaibo. After several years of inactivity, FUNVISIS (The Venezuelan Foundation for Seismological Research) carried out in 1980 a seismic hazard (SHA) for the Uribante Caparo Hydroelectric Project southwest Venezuela. In 1989, MARAVEN, an operating company of PETROLE0S DE VENEUELA S.A. (PDVSA) undertook the project of a products pipeline form Maracaibo to El Vigia, south of Lake Maracaibo. Again, FUNVISIS was contracted to carry out a SHA, which included the digging of 5 trenches, which were supplemented with five more trenches for the COLM project. Trenching activity contined in Venezuela in the framework of SHA project, under the direction of Dr. Audemard. In 2001 Venezuelan trenching experience was exported to the neighboring Colombia as e Dr. Audemard t undertook a palaoseismicity project which included the digging of five trenches. In conclusion, paleoseismicty studies have given us the possibility of extending the scope of both instrumental and historical seismicity by some 10,000 years, trenching has

  16. Phytoextraction crop disposal--an unsolved problem.

    Science.gov (United States)

    Sas-Nowosielska, A; Kucharski, R; Małkowski, E; Pogrzeba, M; Kuperberg, J M; Kryński, K

    2004-01-01

    Several methods of contaminated crop disposal after phytoextraction process (composting, compaction, incineration, ashing, pyrolysis, direct disposal, liquid extraction) have been described. Advantages and disadvantages of methods are presented and discussed. Composting, compaction and pyrolysis are the pretreatment steps, since significant amount of contaminated biomass will still exist after each of the process. Four methods of final disposal were distinguished: incineration, direct disposal, ashing and liquid extraction. Among them, incineration (smelting) is proposed as the most feasible, economically acceptable and environmentally sound.

  17. A Numerical Model for Natural Backfill of Pipeline Trenches Subjected to Unidirectional/Oscillatory Flows

    Institute of Scientific and Technical Information of China (English)

    LIANG Dong-fang; CHENG Liang; Kervin YEOW

    2005-01-01

    A numerical model for the self-burial of a pipeline trench is developed. Morphological evolutions of a pipeline trench under steady-current or oscillatory-flow conditions are simulated with/without a pipeline inside the trench. The oscillatory flow in this study represents the action of waves. The two-dimensional Reynolds-averaged continuity and Navier-Stokes equations with the standard k-ε turbulence closure, as well as the sediment transport equations, are solved with the finite difference method in a curvilinear coordinate system. Both bed and suspended loads of sediment transport are included in the morphological model. Because of the lack of experimental data on the backfilling of pipeline trenches, the numerical model is firetly verified against three closely-relevant experiments available in literature. A detailed measurement of the channel migration phenomenon under steady currents is employed for the assessment of the integral performance of the model. The two experimental results from U-tube tests are used to validate the model's ability in predicting oscillatory flows. Different time-marching schemes are employed for the morphological computation under unidirectional and oscillatory conditions. It is found that vortex motions within the trench play an important role in the trench development.

  18. Trench foot: the medical response in the first World War 1914-18.

    Science.gov (United States)

    Atenstaedt, Robert L

    2006-01-01

    The approaching 90-year anniversary of United States entry into the Great War is an apt time to examine the response to trench foot (now called nonfreezing cold injury [NFCI]) in this conflict. Trench foot appeared in the winter of 1914, characterized by pedal swelling, numbness, and pain. It was quickly recognized by military-medical authorities. There was little debate over whether it was frostbite or new condition, and it was quickly accepted as a specific disease. The major etiologies proposed were exposure, diet, and infection. The opinion emerged that it was caused by circulatory changes in the foot caused by cold, wet, and pressure. Predisposing factors included dietary inadequacy and fatigue. A number of labels were first given to the disease. However, the name "trench foot" was eventually officially sanctioned. Trench foot became a serious problem for the Allies, leading to 75 000 casualties in the British and 2000 in the American forces. Therapy for trench foot involved a number of conventional, tried-and-tested, and conservative methods. Some more innovative techniques were used. Amputation was only used as a last resort. Prevention involved general measures to improve the trench environment; modification of the footwear worn by the men; and the provision of greases to protect them from moisture. The medical reaction to this condition seems to have been relatively effective. The causation was identified, and prophylactic measures were introduced to fit this model; these seem to have been successful in reducing the prevalence of the condition by 1917-18.

  19. Morning Frost in Trench Dug by Phoenix, Sol 113 (False Color)

    Science.gov (United States)

    2008-01-01

    This image from the Surface Stereo Imager on NASA's Phoenix Mars Lander shows morning frost inside the 'Snow White' trench dug by the lander, in addition to subsurface ice exposed by use of a rasp on the floor of the trench. The camera took this image at about 9 a.m. local solar time during the 113th Martian day of the mission (Sept. 18, 2008). Bright material near and below the four-by-four set of rasp holes in the upper half of the image is water-ice exposed by rasping and scraping in the trench earlier the same morning. Other bright material especially around the edges of the trench, is frost. Earlier in the mission, when the sun stayed above the horizon all night, morning frost was not evident in the trench. This image is presented in false color that enhances the visibility of the frost. The trench is 4 to 5 centimeters (about 2 inches) deep, about 23 centimeters (9 inches) wide. Phoenix landed on a Martian arctic plain on May 25, 2008. The mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is led by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development was by Lockheed Martin Space Systems, Denver.

  20. Efficiency Enhancement of Nanoporous Silicon/Polycrystalline-Silicon Solar Cells by Application of Trenched Electrodes

    Directory of Open Access Journals (Sweden)

    Kuen-Hsien Wu

    2014-01-01

    Full Text Available Trenched electrodes were proposed to enhance the short-circuit current and conversion efficiency of polycrystalline-silicon (poly-Si solar cells with nanoporous silicon (NPS surface layers. NPS films that served as textured surface layers were firstly prepared on heavily doped p+-type (100 poly-Si wafers by anodic etching process. Interdigitated trenches were formed in the NPS layers by a reactive-ion-etch (RIE process and Cr/Al double-layered metal was then deposited to fill the trenches and construct trenched-electrode-contacts (TEC’s. Cells with TEC structures (called “TEC cells” obtained 5.5 times higher short-circuit current than that of cells with planar electrode contacts (called “non-TEC cells”. Most significantly, a TEC cell achieved 8 times higher conversion efficiency than that of a non-TEC cell. The enhanced short-circuit current and conversion efficiency in TEC cells were ascribed to the reduced overall series resistance of devices. In a TEC cell, trenched electrodes provided photocurrent flowing routes that directly access the poly-Si substrates without passing through the high resistive NPS layers. Therefore, the application of NPS surface layers with trenched electrodes is a novel approach to development of highly efficient poly-Si solar cells.

  1. Concept for Underground Disposal of Nuclear Waste

    Science.gov (United States)

    Bowyer, J. M.

    1987-01-01

    Packaged waste placed in empty oil-shale mines. Concept for disposal of nuclear waste economically synergistic with earlier proposal concerning backfilling of oil-shale mines. New disposal concept superior to earlier schemes for disposal in hard-rock and salt mines because less uncertainty about ability of oil-shale mine to contain waste safely for millenium.

  2. 48 CFR 2845.603 - Disposal methods.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Disposal methods. 2845.603 Section 2845.603 Federal Acquisition Regulations System DEPARTMENT OF JUSTICE Contract Management GOVERNMENT PROPERTY Reporting, Redistribution, and Disposal of Contractor Inventory 2845.603 Disposal...

  3. 48 CFR 945.603 - Disposal methods.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Disposal methods. 945.603 Section 945.603 Federal Acquisition Regulations System DEPARTMENT OF ENERGY CONTRACT MANAGEMENT GOVERNMENT PROPERTY Reporting, Redistribution, and Disposal of Contractor Inventory 945.603 Disposal methods....

  4. Concepts and data-collection techniques used in a study of the unsaturated zone at a low-level radioactive-waste disposal site near Sheffield, Illinois

    Science.gov (United States)

    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)

  5. In situ grouting of low-level burial trenches with a cement-based grout at Oak Ridge National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Francis, C.W.; Spence, R.D.; Tamura, T.; Spalding, B.P.

    1993-01-01

    A technology being evaluated for use in the closure of one of the low-level radwaste burial grounds at ORNL is trench stabilization using a cement-based grout. To demonstrate the applicability and effectiveness of this technology, two interconnecting trenches in SWSA 6 were selected as candidates for in situ grouting with a particulate grout. The primary objective was to demonstrate the increased trench stability (characterized by trench penetration tests) and the decreased potential for leachate migration (characterized by hydraulic conductivity tests) following in situ injection of a particulate grout into the waste trenches. Stability against trench subsidence is a critical issue. For example, construction of impermeable covers to seal the trenches will be ineffectual unless subsequent trench subsidence is permanently suspended. A grout composed of 39% Type 1 Portland cement, 55.5% Class F fly ash, and 5.5% bentonite mixed at 12.5 lb/gal of water was selected. Before the trenches were grouted, the primary characteristics relating to physical stability, hydraulic conductivity, and void volume of the trenches were determined. Their physical stability was evaluated using soil-penetration tests.

  6. Unreviewed Disposal Question Evaluation: Impact of New Information since 2008 PA on Current Low-Level Solid Waste Operations

    Energy Technology Data Exchange (ETDEWEB)

    Flach, G.; Smith, F.; Hamm, L.; Butcher, T.

    2014-10-06

    of this UDQE has rendered the projected final SOF for SLIT9 less than the WITS Admin Limit. With respect to future disposal unit operations in the East Slit Trench Group, consideration of new information for Slit Trench#14 (SLIT14) reduced the current SOF for the limiting All-Pathways 200-1000 year period (AP2) by an order of magnitude and by one quarter for the Beta-Gamma 12-100 year period (BG2) pathway. On the balance, updates to K{sub d} values and dose factors and elimination of CDP factors (generally favorable) more than compensated for the detrimental impact of a more rigorous treatment of plume dispersion. These observations suggest that future operations in the East Slit Trench Group can be conducted with higher confidence using current inventory limits, and that limits could be increased if desired for future low-level waste disposal units. The same general conclusion applies to future ST’s in the West Slit Trench Group based on the Impacted Final SOFs for existing ST’s in that area.

  7. Disposal of spent nuclear fuel

    Energy Technology Data Exchange (ETDEWEB)

    1979-12-01

    This report addresses the topic of the mined geologic disposal of spent nuclear fuel from Pressurized Water Reactors (PWR) and Boiling Water Reactors (BWR). Although some fuel processing options are identified, most of the information in this report relates to the isolation of spent fuel in the form it is removed from the reactor. The characteristics of the waste management system and research which relate to spent fuel isolation are discussed. The differences between spent fuel and processed HLW which impact the waste isolation system are defined and evaluated for the nature and extent of that impact. What is known and what needs to be determined about spent fuel as a waste form to design a viable waste isolation system is presented. Other waste forms and programs such as geologic exploration, site characterization and licensing which are generic to all waste forms are also discussed. R and D is being carried out to establish the technical information to develop the methods used for disposal of spent fuel. All evidence to date indicates that there is no reason, based on safety considerations, that spent fuel should not be disposed of as a waste.

  8. Social dimensions of nuclear waste disposal

    Energy Technology Data Exchange (ETDEWEB)

    Grunwald, Armin [Karlsruhe Institute of Technology, Karlsruhe (Germany). Inst. for Technology Assessment and Systems Analysis

    2015-07-01

    Nuclear waste disposal is a two-faceted challenge: a scientific and technological endeavour, on the one hand, and confronted with social dimensions, on the other. In this paper I will sketch the respective social dimensions and will give a plea for interdisciplinary research approaches. Relevant social dimensions of nuclear waste disposal are concerning safety standards, the disposal 'philosophy', the process of determining the disposal site, and the operation of a waste disposal facility. Overall, cross-cutting issues of justice, responsibility, and fairness are of major importance in all of these fields.

  9. TECHNOLOGICAL WASTE DISPOSAL BY SUBSURFACE INJECTION TECHNOLOGY

    Directory of Open Access Journals (Sweden)

    Janković Branimir

    2002-12-01

    Full Text Available The application of oilfield and solution mining technology to subsurface disposal of technological wastes has proven to be an environmentally, technically and economically suitable method for the disposal of the waste generated in petroleum industry as well as other industrial branches. This paper describes the subsurface injection technology, the disposal formation characteristics, the waste disposal well design, evaluates the environmental impact of above mentioned technology and proposes a solutions for disposing of technological wastes in Croatia or nerby region by implementing underground injection technology according to the world experience (the paper is published in Croatian.

  10. DUSTMS-D: DISPOSAL UNIT SOURCE TERM - MULTIPLE SPECIES - DISTRIBUTED FAILURE DATA INPUT GUIDE.

    Energy Technology Data Exchange (ETDEWEB)

    SULLIVAN, T.M.

    2006-01-01

    Performance assessment of a low-level waste (LLW) disposal facility begins with an estimation of the rate at which radionuclides migrate out of the facility (i.e., the source term). The focus of this work is to develop a methodology for calculating the source term. In general, the source term is influenced by the radionuclide inventory, the wasteforms and containers used to dispose of the inventory, and the physical processes that lead to release from the facility (fluid flow, container degradation, wasteform leaching, and radionuclide transport). Many of these physical processes are influenced by the design of the disposal facility (e.g., how the engineered barriers control infiltration of water). The complexity of the problem and the absence of appropriate data prevent development of an entirely mechanistic representation of radionuclide release from a disposal facility. Typically, a number of assumptions, based on knowledge of the disposal system, are used to simplify the problem. This has been done and the resulting models have been incorporated into the computer code DUST-MS (Disposal Unit Source Term-Multiple Species). The DUST-MS computer code is designed to model water flow, container degradation, release of contaminants from the wasteform to the contacting solution and transport through the subsurface media. Water flow through the facility over time is modeled using tabular input. Container degradation models include three types of failure rates: (a) instantaneous (all containers in a control volume fail at once), (b) uniformly distributed failures (containers fail at a linear rate between a specified starting and ending time), and (c) gaussian failure rates (containers fail at a rate determined by a mean failure time, standard deviation and gaussian distribution). Wasteform release models include four release mechanisms: (a) rinse with partitioning (inventory is released instantly upon container failure subject to equilibrium partitioning (sorption) with

  11. Life Cycle Analysis for Treatment and Disposal of PCB Waste at Ashtabula and Fernald

    Energy Technology Data Exchange (ETDEWEB)

    Morris, M.I.

    2001-01-11

    This report presents the use of the life cycle analysis (LCA) system developed at Oak Ridge National Laboratory (ORNL) to assist two U.S. Department of Energy (DOE) sites in Ohio--the Ashtabula Environmental Management Project near Cleveland and the Fernald Environmental Management Project near Cincinnati--in assessing treatment and disposal options for polychlorinated biphenyl (PCB)-contaminated low-level radioactive waste (LLW) and mixed waste. We will examine, first, how the LCA process works, then look briefly at the LCA system's ''toolbox,'' and finally, see how the process was applied in analyzing the options available in Ohio. As DOE nuclear weapons facilities carry out planned decontamination and decommissioning (D&D) activities for site closure and progressively package waste streams, remove buildings, and clean up other structures that have served as temporary waste storage locations, it becomes paramount for each waste stream to have a prescribed and proven outlet for disposition. Some of the most problematic waste streams throughout the DOE complex are PCB low-level radioactive wastes (liquid and solid) and PCB low-level Resource Conservation and Recovery Act (RCRA) liquid and solid wastes. Several DOE Ohio Field Office (OH) sites have PCB disposition needs that could have an impact on the critical path of the decommissioning work of these closure sites. The Ashtabula Environmental Management Project (AEMP), an OH closure site, has an urgent problem with disposition of soils contaminated by PCB and low-level waste at the edge of the site. The Fernald Environmental Management Project (FEMP), another OH closure site, has difficulties in timely disposition of its PCB-low-level sludges and its PCB low-level RCRA sludges in order to avoid impacting the critical path of its D&D activities. Evaluation of options for these waste streams is the subject of this report. In the past a few alternatives for disposition of PCB low-level waste

  12. 地下连续墙成槽施工槽壁稳定机制分析%ANALYSIS OF TRENCH FACE STABILITY OF DIAPHRAGM WALL PANEL DURING SLURRY TRENCHING

    Institute of Scientific and Technical Information of China (English)

    丁勇春; 李光辉; 程泽坤; 王建华; 陈锦剑

    2013-01-01

    Some key issues including inner and outer influencing factors of trench face stability,overall and local instability mechanism of trench face,and stress path of soil element near trench face are discussed in detail to investigate the trench face stability and instability performance during slurry trenching for diaphragm wall panels. The research results show that shallow ground collapse is the major trench face overall instability pattern during slurry trenching,and trench face local collapse is commonly caused by heavily sandy of soil and excessive fluctuation of slurry flux level. Some precautionary construction measures,including increasing unit weight of slurry appropriately,raising slurry fluid level,pre-reclamation of trench face soil,control of trenching machine overloading and manipulation of soil disturbance during slurry trenching,are the most effective countermeasures to ensure the trench face stability. The trench face stability decreases with the dissipation of negative pore pressure after slurry trenching. Therefore,reinforcement cages should be placed into trench in time and concrete should be casted as soon as possible to guarantee the trench face stability.%  针对地下连续墙成槽施工过程中的槽壁稳定性及其失稳现象,分别从地下连续墙槽壁稳定影响因素、槽壁整体及局部失稳机制、不同施工阶段槽壁土体的应力路径3个方面进行分析。研究结果表明:浅层失稳是泥浆护壁成槽施工过程中槽壁整体失稳的主要形式,局部失稳多由槽壁土体砂性较重及槽段内泥浆液面波动过大引起;适当增加泥浆比重、提高泥浆液面标高、槽壁预加固、控制成槽机械地面超载及降低开挖对土体的扰动可有效保证槽壁的稳定;开挖后槽壁稳定性会随土体负孔隙水压力的消散而下降,成槽后应及时吊放钢筋笼并及早浇筑混凝土。

  13. Ultra-compact three-port trench-based photonic couplers in ion-exchanged glass waveguides

    Science.gov (United States)

    Liu, Ke; Huang, Hui; Mu, Si Xuan; Lin, Hai; MacFarlane, Duncan L.

    2013-11-01

    An ultra-compact three-port photonic coupler is proposed on a glass substrate based upon a principle of frustrated total internal reflection. A single slash shape narrow trench at the “T” intersection of two ion-exchanged waveguides forms the coupler and is aligned 45° to the waveguides. The three-dimensional finite difference time domain (FDTD) theory is used to simulate the parameterization of the coupler, such as splitting ratios and efficiency versus trench widths, trench lengths, trench locations, and trench angles. The waveguide model used in FDTD is based on an experimental condition of the K+-Na+ ion-exchange process. A single-mode 6 μm wide glass waveguide at 1550 nm wavelength is fabricated through the analysis of the effective index method. The numerical results show that the arbitrary splitting ratios may be controlled by trench widths and trench angles. Comparing to Si, InP and GaAs materials, trench-based coupler on glasses may readily achieve the manufacturability since the low index of glass waveguides results in a wider trench opening. Taking advantage of low loss ion-exchanged waveguides, the high efficiency and short interaction length photonic couplers have a great potential to be integrated for large scale glass-based photonic circuits.

  14. Numerical analysis of the Gibbs-Thomson effect on trench-filling epitaxial growth of 4H-SiC

    Science.gov (United States)

    Mochizuki, Kazuhiro; Ji, Shiyang; Kosugi, Ryoji; Kojima, Kazutoshi; Yonezawa, Yoshiyuki; Okumura, Hajime

    2016-03-01

    A steady-state two-dimensional diffusion equation was numerically analyzed to examine the rate of homoepitaxial growth on a trenched 4H-SiC substrate. The radii of curvature at the top and bottom of the trenches were used to take the Gibbs-Thomson effect into account in the analysis based on the conventional boundary-layer model. When the trench pitch was less than or equal to 6.0 µm, the measured dependence of the growth rate on the trench pitch was found to be explained by the Gibbs-Thomson effect on the vapor-phase diffusion of growing species.

  15. Generic Crystalline Disposal Reference Case

    Energy Technology Data Exchange (ETDEWEB)

    Painter, Scott Leroy [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Chu, Shaoping [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Harp, Dylan Robert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Perry, Frank Vinton [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Wang, Yifeng [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-02-20

    A generic reference case for disposal of spent nuclear fuel and high-level radioactive waste in crystalline rock is outlined. The generic cases are intended to support development of disposal system modeling capability by establishing relevant baseline conditions and parameters. Establishment of a generic reference case requires that the emplacement concept, waste inventory, waste form, waste package, backfill/buffer properties, EBS failure scenarios, host rock properties, and biosphere be specified. The focus in this report is on those elements that are unique to crystalline disposal, especially the geosphere representation. Three emplacement concepts are suggested for further analyses: a waste packages containing 4 PWR assemblies emplaced in boreholes in the floors of tunnels (KBS-3 concept), a 12-assembly waste package emplaced in tunnels, and a 32-assembly dual purpose canister emplaced in tunnels. In addition, three failure scenarios were suggested for future use: a nominal scenario involving corrosion of the waste package in the tunnel emplacement concepts, a manufacturing defect scenario applicable to the KBS-3 concept, and a disruptive glaciation scenario applicable to both emplacement concepts. The computational approaches required to analyze EBS failure and transport processes in a crystalline rock repository are similar to those of argillite/shale, with the most significant difference being that the EBS in a crystalline rock repository will likely experience highly heterogeneous flow rates, which should be represented in the model. The computational approaches required to analyze radionuclide transport in the natural system are very different because of the highly channelized nature of fracture flow. Computational workflows tailored to crystalline rock based on discrete transport pathways extracted from discrete fracture network models are recommended.

  16. Fracking, wastewater disposal, and earthquakes

    Science.gov (United States)

    McGarr, Arthur

    2016-03-01

    In the modern oil and gas industry, fracking of low-permeability reservoirs has resulted in a considerable increase in the production of oil and natural gas, but these fluid-injection activities also can induce earthquakes. Earthquakes induced by fracking are an inevitable consequence of the injection of fluid at high pressure, where the intent is to enhance permeability by creating a system of cracks and fissures that allow hydrocarbons to flow to the borehole. The micro-earthquakes induced during these highly-controlled procedures are generally much too small to be felt at the surface; indeed, the creation or reactivation of a large fault would be contrary to the goal of enhancing permeability evenly throughout the formation. Accordingly, the few case histories for which fracking has resulted in felt earthquakes have been due to unintended fault reactivation. Of greater consequence for inducing earthquakes, modern techniques for producing hydrocarbons, including fracking, have resulted in considerable quantities of coproduced wastewater, primarily formation brines. This wastewater is commonly disposed by injection into deep aquifers having high permeability and porosity. As reported in many case histories, pore pressure increases due to wastewater injection were channeled from the target aquifers into fault zones that were, in effect, lubricated, resulting in earthquake slip. These fault zones are often located in the brittle crystalline rocks in the basement. Magnitudes of earthquakes induced by wastewater disposal often exceed 4, the threshold for structural damage. Even though only a small fraction of disposal wells induce earthquakes large enough to be of concern to the public, there are so many of these wells that this source of seismicity contributes significantly to the seismic hazard in the United States, especially east of the Rocky Mountains where standards of building construction are generally not designed to resist shaking from large earthquakes.

  17. Waste Disposal: The PRACLAY Programme

    Energy Technology Data Exchange (ETDEWEB)

    De Bruyn, D

    2000-07-01

    Principal achievements in 2000 with regard to the PRACLAY programme are presented. The PRACLAY project has been conceived: (1) to demonstrate the construction and the operation of a gallery for the disposal of HLW in a clay formation; (2) to improve knowledge on deep excavations in clay through modelling and monitoring; (3) to design, install and operate a complementary mock-up test (OPHELIE) on the surface. In 1999, efforts were focussed on the operation of the OPHELIE mock-up and the CLIPEX project to monitor the evolution of hydro-mechanical parameters of the Boom Clay Formation near the face of a gallery during excavation.

  18. Outline of Seafloor Observation Network for Earthquakes and Tsunamis along the Japan Trench (S-net)

    Science.gov (United States)

    Uehira, Kenji; Kanazawa, Toshihiko; Mochizuki, Masashi; Fujimoto, Hiromi; Noguchi, Shin-ichi; Shinbo, Takashi; Shiomi, Katsuhiko; Kunugi, Takashi; Aoi, Shin; Matsumoto, Takumi; Sekiguchi, Shoji; Okada, Yoshimitsu; Shinohara, Masanao; Yamada, Tomoaki

    2016-04-01

    Seafloor Observation Network for Earthquakes and Tsunamis along the Japan Trench (S-net) project to construct a large-scale seafloor network of cable-linked observatories is in progress around Japan Trench and Kuril Trench in Japan. The main purpose of the S-net project is disaster prevention by providing ground motion and tsunami height data in real time. Such real-time data from the seafloor observatories make it possible to forecast the next-generation early tsunami warning which could precisely predict coastal tsunami height. Also the data may make it possible to forecast an earthquake warning much earlier than the present system. The network consists of 150 ocean bottom observation stations. Ocean bottom fiber optic cables, about 5,700 km in total length, connect the stations to land. Observation stations will be placed on the seafloor off Hokkaido, off Tohoku and off Kanto, in a spacing of about 30 km almost in the direction of East-West (perpendicular to the trench axis) and in a spacing of about 50 - 60 km almost in the direction of North-South (parallel to the trench axis). Each station is equipped with seismometers of three types and two hydro-pressure gauges (tsunami meters) of the same type for redundancy. The digitized data will be transmitted to the data centers, JMA (Japan Meteorological Agency), and so on, using IP network. S-net is supported by MEXT financially.

  19. Resisting and pinning of a nanodrop by trenches on a hysteresis-free surface

    Science.gov (United States)

    Chang, Cheng-Chung; Wu, Cyuan-Jhang; Sheng, Yu-Jane; Tsao, Heng-Kwong

    2016-10-01

    The encounter of a nanodrop with a trench on a hysteresis-free surface is explored by many-body dissipative particle dynamics to show the effect of surface roughness on droplet wetting. A free nanodrop exhibits Brownian motion and the diffusivity decays exponentially with the liquid-solid contact area. In contrast, as the nanodrop sits on a trench, its random motion is constrained. Work must be done to overcome the energy barriers for the transition between free and trapped states. The potential energy landscape is thus constructed based on the force-displacement plot. It is shown that the trench acts as a hydrophobic blemish for capture but like a hydrophilic blemish for escape. A drop always breaks up after detachment from a hydrophilic trench. Therefore, the drop tends to bypass a small trench when it meets one. The macroscopic experiments are performed by fabricating liquid-infused surfaces with extremely low contact angle hysteresis. The experimental observations agree qualitatively with simulation outcomes.

  20. A study of SU-8 photoresist in deep trenches for silicon-embedded microinductors

    Science.gov (United States)

    Laforge, Elias; Rabot, Caroline; Wang, Ningning; Pavlovic, Zoran; McCloskey, Paul; O'Mathúna, Cian

    2016-10-01

    Epoxy-based resist SU-8 is widely used in the development and fabrication of high-aspect-ratio (HAR) MEMS structures. It has proven to be a suitable photoresist combining thick layer coating and good adhesion on silicon substrates as well as possessing good mechanical and chemical stability. However, the trend towards minia- turization and increasing packaging density has pushed the demand for challenging micro-machining processes. As an example, a novel design of a MEMS microinductor requires a dielectric permanent layer coated in deep silicon trenches in order to insulate copper windings from the magnetic material deposited in these trenches. This requires the development of a photolithography process which enables the coating of a void-free layer filling the trenches. In this paper, the use of thick SU-8 photoresist for filling deep silicon trenches is investigated. Different SU-8 formulations are analyzed, processed and results are compared. As a result, an optimized process is developed to achieve void-free filled trenches and a uniform planar layer above them, with near vertical sidewall patterns.

  1. 3D analysis of in-filled trench as passive barriers for ground vibration isolation

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The three-dimensional (3D) problem of the ground vibration isolation by an in-filled trench as a passive barrier is studied theoretically. Integral equations governing Rayleigh wave scattering are derived based on the Green’s solution of Lamb prob-lem. The integral equations are solved accurately and efficiently with an iteration technique. They are used to evaluate the complicated Rayleigh wave field gener-ated by irregular scatterers embedded in an elastic half-space solid. The passive isolation effectiveness of ground vibration by the in-filled trench for screening Rayleigh wave is further studied in detail. Effects of relevant parameters on the effectiveness of vibration isolation are investigated and presented. The results show that a trench filled with stiff backfill material gets a better isolation effect than a soft one, and increasing the depth or width of the in-filled trench also improves its screening effectiveness. The effectiveness and the area of the screened zone are surging with the increase in the length of the in-filled trench.

  2. The centenary of the discovery of trench fever, an emerging infectious disease of World War 1.

    Science.gov (United States)

    Anstead, Gregory M

    2016-08-01

    In 1915, a British medical officer on the Western Front reported on a soldier with relapsing fever, headache, dizziness, lumbago, and shin pain. Within months, additional cases were described, mostly in frontline troops, and the new disease was called trench fever. More than 1 million troops were infected with trench fever during World War 1, with each affected soldier unfit for duty for more than 60 days. Diagnosis was challenging, because there were no pathognomonic signs and symptoms and the causative organism could not be cultured. For 3 years, the transmission and cause of trench fever were hotly debated. In 1918, two commissions identified that the disease was louse-borne. The bacterium Rickettsia quintana was consistently found in the gut and faeces of lice that had fed on patients with trench fever and its causative role was accepted in the 1920s. The organism was cultured in the 1960s and reclassified as Bartonella quintana; it was also found to cause endocarditis, peliosis hepatis, and bacillary angiomatosis. Subsequently, B quintana infection has been identified in new populations in the Andes, in homeless people in urban areas, and in individuals with HIV. The story of trench fever shows how war can lead to the recrudescence of an infectious disease and how medicine approached an emerging infection a century ago.

  3. Three-dimensional laboratory modeling of the Tonga trench and Samoan plume interaction

    Science.gov (United States)

    Druken, K. A.; Kincaid, C. R.; Pockalny, R. A.; Griffiths, R. W.; Hart, S. R.

    2009-12-01

    Plume processes occurring near ridge centers (e.g. Iceland) or mid-plate (e.g. Hawaii) have been well studied; however, the behavior of a plume near a subducting plate is still poorly understood and may in fact differ from the typical expected plume surfacing patterns. We investigate how three-dimensional subduction-driven flow relates to the deformation and dispersal of nearby upwelling plume material and the associated geochemical spatial patterns, with site-specific comparisons to the Tonga trench and Samoan plume system. Eighteen plume-trench laboratory experiments were conducted with varied combinations of subduction motions (down-dip, trench rollback, slab steepening and back-arc extension) and plume parameters (position and temperature.) A phenolic plate and glucose syrup, with a temperature dependent viscosity, are used to model the slab and upper mantle, respectively. Hydraulic pistons control longitudinal, translational and steepening motions of the slab as a simplified kinematic approach to mimic dynamic experiments. Results show that the subduction-induced flow dominates the upwelling strength of the plume, causing a significant portion of the plume head to subduct before reaching the melt zone. The remaining material is entrained around the slab edge into the mantle wedge by the trench rollback-induced flow. The proportion of subducted verses entrained material is predominantly dependent on plume location (relative to the trench) and thermal strength, with additional effects from back-arc extension and plate steepening.

  4. Enhancing filling of interconnect deep trenches using forced convection magneto-electroplating

    Science.gov (United States)

    Said, R. A.

    2006-01-01

    Filling deep trenches and cavities is currently accomplished by copper electro-less plating technology utilizing super-conformal deposition methods. Unlike typical electrolyses processes, where an electric potential is applied between the anodes to activate the plating reaction, electro-less plating relies on chemical agents to activate deposition. To achieve super-conformal deposition, special electrolytic paths must be used. This poses a challenge to the fabrication of narrower trenches, and thus requires the development of other deposition schemes. This work proposes an alternative solution to the filling of deep trenches that avoids the difficulties outlined above, using a forced convection magneto-electroplating method. The technique operates as in typical electrolysis processes, however, with forcing the flow of the plating electrolyte, by hydro-dynamic means, in the presence of an externally applied magnetic field. This arrangement introduces a Lorentz type of force that enhances the transport of deposit species toward desired locations, such as deep regions in interconnect trenches. The proposed method is demonstrated by filling interconnect trenches with aspect ratio as high as 3:1. Quality of samples filled using the proposed magneto-electroplating method is compared with the quality of samples filled by typical electroplating method.

  5. Characterization of shallow trench isolation CMP process and its application

    Science.gov (United States)

    Li, Helen; Zhang, ChunLei; Liu, JinBing; Liu, ZhengFang; Chen, Kuang Han; Gbondo-Tugbawa, Tamba; Ding, Hua; Li, Flora; Lee, Brian; Gower-Hall, Aaron; Chiu, Yang-Chih

    2016-03-01

    Chemical mechanical polishing (CMP) has been a critical enabling technology in shallow trench isolation (STI), which is used in current integrated circuit fabrication process to accomplish device isolation. Excessive dishing and erosion in STI CMP processes, however, create device yield concerns. This paper proposes characterization and modeling techniques to address a variety of concerns in STI CMP. In the past, majority of CMP publications have been addressed on interconnect layers in backend- of-line (BEOL) process. However, the number of CMP steps in front-end-of-line (FEOL) has been increasing in more advanced process techniques like 3D-FinFET and replacement metal gate, as a results incoming topography induced by FEOL CMP steps can no longer be ignored as the topography accumulates and stacks up across multiple CMP steps and eventually propagating to BEOL layers. In this paper, we first discuss how to characterize and model STI CMP process. Once STI CMP model is developed, it can be used for screening design and detect possible manufacturing weak spots. We also work with process engineering team to establish hotspot criteria in terms of oxide dishing and nitride loss. As process technologies move from planar transistor to 3D transistor like FinFet and multi-gate, it is important to accurately predict topography in FEOL CMP processes. These incoming topographies when stacked up can have huge impact in BEOL copper processes, where copper pooling becomes catastrophic yield loss. A calibration methodology to characterize STI CMP step is developed as shown in Figure 1; moreover, this STI CMP model is validated from silicon data collected from product chips not used in calibration stage. Additionally, wafer experimental setup and metrology plan are instrumental to an accurate model with high predictive power. After a model is generated, spec limits and threshold to establish hotspots criteria can be defined. Such definition requires working closely with foundry

  6. Electrical Resistivity Correlation to Vadose Zone Sediment and Pore-Water Composition for the BC Cribs and Trenches Area

    Energy Technology Data Exchange (ETDEWEB)

    Serne, R. Jeffrey; Ward, Anderson L.; Um, Wooyong; Bjornstad, Bruce N.; Rucker, Dale F.; Lanigan, David C.; Benecke, Mark W.

    2009-06-01

    This technical report documents the results of geochemical and soil resistivity characterization of sediment obtained from four boreholes drilled in the BC Cribs and Trench area. Vadose zone sediment samples were obtained at a frequency of about every 2.5 ft from approximately 5 ft bgs to borehole total depth. In total, 505 grab samples and 39 six-inch long cores were obtained for characterization. The pore-water chemical composition data, laboratory-scale soil resistivity and other ancillary physical and hydrologic measurements and analyses described in this report are designed to provide a crucial link between direct measurements on sediments and the surface-based electrical-resistivity information obtained via field surveys. A second goal of the sediment characterization was to measure the total and water-leachable concentrations of key contaminants of concern as a function of depth and distance from the footprints of inactive disposal facilities. The total and water-leachable concentrations of key contaminants will be used to update contaminant distribution conceptual models and to provide more data for improving base-line risk predictions and remedial alternative selections. The ERC “ground truthing” exercise for the individual boreholes showed mixed results. In general, the high concentrations of dissolved salts in the pore waters of sediments from C5923, C5924 and C4191 produced a low resistivity “target” in the processed resistivity field surveys, and variability could be seen in the resistivity data that could relate to the variability in pore- water concentrations but the correlations (regression R2 were mediocre ranging from 0.2 to 0.7 at best; where perfect correlation is 1.0). The field-based geophysical data also seemed to suffer from a sort of vertigo, where looking down from the ground surface, the target (e.g., maximum pore-water salt concentration) depth was difficult to resolve. The best correlations between the field electrical

  7. A Disposable Blood Cyanide Sensor

    Science.gov (United States)

    Tian, Yong; Dasgupta, Purnendu K.; Mahon, Sari B.; Ma, Jian; Brenner, Matthew; Wang, Jian-Hua; Boss, Gerry R.

    2013-01-01

    Deaths due to smoke inhalation in fires are often due to poisoning by HCN. Rapid administration of antidotes can result in complete resuscitation of the patient but judicious dosing requires the knowledge of the level of cyanide exposure. Rapid sensitive means for blood cyanide quantitation are needed. Hydroxocyanocobinamide (OH(CN)Cbi) reacts with cyanide rapidly; this is accompanied by a large spectral change. The disposable device consists of a pair of nested petri dish bottoms and a single top that fits the outer bottom dish. The top cover has a diametrically strung porous polypropylene membrane tube filled with aqueous OH(CN)Cbi. One end of the tube terminates in an amber (583 nm) light emitting diode; the other end in a photodiode via an acrylic optical fiber. An aliquot of the blood sample is put in the inner dish, the assembly covered and acid is added through a port in the cover. Evolved HCN diffuses into the OH(CN)Cbi solution and the absorbance in the long path porous membrane tube cell is measured within 160s. The LOD was 0.047, 1.0, 0.15, 5.0 and 2.2 μM, respectively, for water (1 mL), bovine blood (100 μL, 1 mL), and rabbit blood (20μL, 50 μL). RSDs were cyanide in rabbit and human blood. The disposable device permits field measurement of blood cyanide in < 4 min. PMID:23473259

  8. Disposable optics for microscopy diagnostics.

    Science.gov (United States)

    Vilmi, Pauliina; Varjo, Sami; Sliz, Rafal; Hannuksela, Jari; Fabritius, Tapio

    2015-11-20

    The point-of-care testing (POCT) is having increasing role on modern health care systems due to a possibility to perform tests for patients conveniently and immediately. POCT includes lot of disposable devices because of the environment they are often used. For a disposable system to be reasonably utilized, it needs to be high in quality but low in price. Optics based POCT systems are interesting approach to be developed, and here we describe a low-cost fabrication process for microlens arrays for microscopy. Lens arrays having average lens diameter of 222 μm with 300 μm lens pitch were fabricated. The lenses were characterized to have standard deviation of 0.06 μm in height and 4.61 μm in diameter. The resolution limit of 3.9μm is demonstrated with real images, and the images were compared with ones made with glass and polycarbonate lens arrays. The image quality is at the same level than with the glass lenses and the manufacturing costs are very low, thus making them suitable for POCT applications.

  9. Disposable optics for microscopy diagnostics

    Science.gov (United States)

    Vilmi, Pauliina; Varjo, Sami; Sliz, Rafal; Hannuksela, Jari; Fabritius, Tapio

    2015-11-01

    The point-of-care testing (POCT) is having increasing role on modern health care systems due to a possibility to perform tests for patients conveniently and immediately. POCT includes lot of disposable devices because of the environment they are often used. For a disposable system to be reasonably utilized, it needs to be high in quality but low in price. Optics based POCT systems are interesting approach to be developed, and here we describe a low-cost fabrication process for microlens arrays for microscopy. Lens arrays having average lens diameter of 222 μm with 300 μm lens pitch were fabricated. The lenses were characterized to have standard deviation of 0.06 μm in height and 4.61 μm in diameter. The resolution limit of 3.9μm is demonstrated with real images, and the images were compared with ones made with glass and polycarbonate lens arrays. The image quality is at the same level than with the glass lenses and the manufacturing costs are very low, thus making them suitable for POCT applications.

  10. Impact of the OSHA trench and excavation standard on fatal injury in the construction industry.

    Science.gov (United States)

    Suruda, Anthony; Whitaker, Brad; Bloswick, Donald; Philips, Peter; Sesek, Richard

    2002-10-01

    In 1989 the US Occupational Safety & Health Administration revised the excavation and trenching standard. We examined fatal injuries from trench cave-in in the construction industry for five year periods before and after the revision in the 47 US states for which data were available for both periods. There was a 2-fold decline in the rate of fatal injury after revision of the standard, which substantially exceeded the decline in other causes of fatal injury in the construction industry during the same period. The decline was somewhat greater in large business firms but was evident in construction firms of all size classes. The fatality rate from trench cave-in in union construction workers was approximately half that of nonunion workers, but we were unable to determine whether this was best explained by union status, employment of union workers at larger construction firms, or both. This study provides evidence for the effectiveness of OSHA regulation in preventing fatal work injury.

  11. Significance of broad scale deformation of incoming plates at ocean trenches.

    Science.gov (United States)

    Ranero, C. R.; Calahorrano, A.; Grevemeyer, I.; Barckhausen, U.; Reichert, C. J.

    2012-12-01

    Recent seismic experiments in several ocean trenches indicate that oceanic lithosphere undergoes profound chemical changes due to percolation of water into the mantle along faults formed by bending-related deformation. When compared to earthquake activity the depth of mantle alteration seems to be related to the elastic thickness of the plate and thus controlled by bending stresses. This finding contrasts with previous speculation that large-great trench-outer-rise earthquakes were important in the formation of paths for water penetration into the plate. Large-great trench-outer-rise earthquakes are probably related to slab pull during decoupling along the interplate boundary and not necessarily controlled by bending stresses. Thus, current findings may seem to indicate that plate age and related elastic thickness at trenches may be be the key parameter that controls the amount of hydration that may occur in a plate. New multichannel seismic reflection images from northern Chile and a compilation of multibeam bathymetry display a remarkable variability of bending-related deformation along several hundreds kilometres of the subduction zone where plate age does not change significantly indicating that deformation and probably hydration might be very variable in space. A set of seismic profiles collected perpendicular to the trench and running several hundreds of kilometers into the incoming plate show that the bending-related deformation of the oceanic plate reaches the mantle well before the lithosphere plunges into the trench and develops a marked bend-faulting fabric observable in bathymetric maps. Similar conclusions can be reached from seismic images across the outer rise of the Cocos plate entering the Middle America Trench. Also, the combination of seismic images and swath bathymetry along the Chile trench shows a remarkable lateral variability in the intensity and style of deformation at the trench. The deformation appears to be controlled by the stresses

  12. Dynamic soil properties of some deep trenches in Mashhad city, NE Iran

    Indian Academy of Sciences (India)

    Azam Ghazi; Naser Hafezi Moghadas; Hossein Sadeghi; Mohammad Ghafoori; Gholam Reza Lashkaripour

    2015-10-01

    Microtremor survey is achieved in order to evaluate the dynamical characteristics of surface layers. For this purpose, 13 trenches were selected and microtremor measurements were performed at the top and bottom of each trench. Floor spectral ratio (FRS) analysis was accomplished to obtain frequency and amplification of the trenches. The results of microtremor were compared with 1D equivalent linear analysis. Most of the fundamental frequencies obtained by 1D analysis are in good agreement with those calculated by microtremor technique. Irregularities in surface and subsurface geomorphic conditions tend to have differences in results obtained by both mentioned methods. Damping ratios were derived from the half power bandwidth method. The damping ratio varied between 2.1 in fine grain soils and 6.6 in sand soils.

  13. Widespread Occurrence of Trenching Patterns in the Granulation Field: Evidence for Roll Convection?

    CERN Document Server

    Getling, A V

    2007-01-01

    Time-averaged series of granulation images are analysed using COLIBRI, a purpose-adapted version of a code originally developed to detect straight or curvilinear features in aerospace images. The algorithm of image processing utilises a nonparametric statistical criterion that identifies a straight-line segment as a linear feature (lineament) if the photospheric brightness at a certain distance from this line is on both sides stochastically lower or higher than at the line itself. Curvilinear features can be detected as chains of lineaments, using a criterion modified in some way. Once the input parameters used by the algorithm are properly adjusted, the algorithm highlights ``ridges'' and ``trenches'' in the relief of the brightness field, drawing white and dark lanes. The most remarkable property of the trenching patterns is a nearly-universally-present parallelism of ridges and trenches. Since the material upflows are brighter than the downflows, the alternating parallel light and dark lanes should reflect...

  14. Environmental considerations for the disposal of PBB-contaminated animals and wastes.

    Science.gov (United States)

    Shah, B P

    1978-01-01

    Accidental contamination of livestock feed in 1973 by polybrominated biphenyls (PBB) led to the destruction of over 30,000 animals in Michigan. Animal carcasses of mostly dairy cattle along with some beef cattle, hogs, sheep and rabbits destroyed under the Federal Food and Drug Administration guidelines were disposed on the land at an environmentally safe site in Kalkaska County, Michigan. The geology and hydrology of the disposal site on state-owned land is considered favorable for the disposal of contaminated carcasses and to prevent any migration of PBBs into ground and surface waters of the area. Materials underneath the site are predominantly sand with layers of silts and clays of glacial origin. The vertical isolation from the surface to the water table is over 90 ft, and the horizontal isolation to the privately owned properties and surface water bodies is well over 1.5 mile in all directions. The site design provides necessary safeguards for minimizing surface water infiltration into disposal trenches and maximizing the protection to the environment. A series of water wells in the direction of flow are established for monitoring groundwater quality for years to come. A 40-acre Gratiot County landfill located near St. Louis, Michigan, has received 269,000 lb of wastes containing 60 to 70% PBBs between 1971 and 1973. PBB wastes are intermixed with general refuse at various depths predominantly in the eastern half of the landfill. Phase I of the hydrogeological investigation shows that the landfill is situated immediately above the groundwater aquifer and a divide. Recently drilled test wells show traces of PBBs in the aquifer in all directions. Additional studies are planned in the near future for corrective measures and monitoring. Images FIGURE 4. PMID:209986

  15. Corrective Action Plan for Corrective Action Unit 139: Waste Disposal Sites, Nevada Test Site, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    NSTec Environmental Restoration

    2007-07-01

    Corrective Action Unit (CAU) 139, Waste Disposal Sites, is listed in the Federal Facility Agreement and Consent Order (FFACO) of 1996 (FFACO, 1996). CAU 139 consists of seven Corrective Action Sites (CASs) located in Areas 3, 4, 6, and 9 of the Nevada Test Site (NTS), which is located approximately 65 miles (mi) northwest of Las Vegas, Nevada (Figure 1). CAU 139 consists of the following CASs: CAS 03-35-01, Burn Pit; CAS 04-08-02, Waste Disposal Site; CAS 04-99-01, Contaminated Surface Debris; CAS 06-19-02, Waste Disposal Site/Burn Pit; CAS 06-19-03, Waste Disposal Trenches; CAS 09-23-01, Area 9 Gravel Gertie; and CAS 09-34-01, Underground Detection Station. Details of the site history and site characterization results for CAU 139 are provided in the approved Corrective Action Investigation Plan (CAIP) (U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office [NNSA/NSO], 2006) and in the approved Corrective Action Decision Document (CADD) (NNSA/NSO, 2007). The purpose of this Corrective Action Plan (CAP) is to present the detailed scope of work required to implement the recommended corrective actions as specified in Section 4.0 of the approved CADD (NNSA/NSO, 2007). The approved closure activities for CAU 139 include removal of soil and debris contaminated with plutonium (Pu)-239, excavation of geophysical anomalies, removal of surface debris, construction of an engineered soil cover, and implementation of use restrictions (URs). Table 1 presents a summary of CAS-specific closure activities and contaminants of concern (COCs). Specific details of the corrective actions to be performed at each CAS are presented in Section 2.0 of this report.

  16. Annual Performance Report April 2015 Through March 2016 for the Shiprock, New Mexico, Disposal Site

    Energy Technology Data Exchange (ETDEWEB)

    Kautsky, Mark [USDOE Office of Legacy Management (LM), Washington, DC (United States); Miller, David [Navarro Research and Engineering, Oak Ridge, TN (United States)

    2016-10-01

    This annual report evaluates the performance of the groundwater remediation system at the Shiprock, New Mexico, Disposal Site (Shiprock site) for the period April 2015 through March 2016. The Shiprock site, a former uranium-ore processing facility remediated under the Uranium Mill Tailings Radiation Control Act, is managed by the U.S. Department of Energy (DOE) Office of Legacy Management. This annual report is based on an analysis of groundwater quality and groundwater level data obtained from site monitoring wells and the groundwater flow rates associated with the extraction wells, drains, and seeps. Background The Shiprock mill operated from 1954 to 1968 on property leased from the Navajo Nation. Remediation of surface contamination, including stabilization of mill tailings in an engineered disposal cell, was completed in 1986. During mill operation, nitrate, sulfate, uranium, and other milling-related constituents leached into underlying sediments and contaminated groundwater in the area of the mill site. In March 2003, DOE initiated active remediation of groundwater at the site using extraction wells and interceptor drains. At that time, DOE developed a baseline performance report that established specific performance standards for the Shiprock site groundwater remediation system. The Shiprock site is divided into two distinct areas: the floodplain and the terrace. The floodplain remediation system consists of two groundwater extraction wells, a seep collection drain, and two collection trenches (Trench 1 and Trench 2). The terrace remediation system consists of nine groundwater extraction wells, two collection drains (Bob Lee Wash and Many Devils Wash), and a terrace drainage channel diversion structure. All extracted groundwater is pumped into a lined evaporation pond on the terrace. Compliance Strategy and Remediation Goals As documented in the Groundwater Compliance Action Plan, the U.S. Nuclear Regulatory Commission–approved compliance strategy for the

  17. Recent Progress of Power Trench MOS Industrialization Technology%功率Trench MOS器件工业化技术的新进展

    Institute of Scientific and Technical Information of China (English)

    曾军; M N Darwish; R A Blanchard

    2012-01-01

    简要地回顾和探讨了垂直型功率Trench金属氧化层半导体场效晶体管(MOSFET)器件(即Trench MOS)的技术发展及其当前工业化生产水平.重点讨论了适用于工业界大规模生产的,能同时降低正向导通损耗和瞬态开关损耗的器件结构和制造工艺,并举例给出了目前工业界最先进30V Trench MOS产品综合技术指标(FOM)的比较.最后,讨论了沟槽技术在基于SiC材料的功率MOSFET器件生产中的应用.

  18. AMS measurement of 10Be concentrations in marine sediments from Chile Trench at the TANDAR laboratory

    Science.gov (United States)

    Rodrigues, D.; Arazi, A.; Fernández Niello, J. O.; Martí, G. V.; Negri, A. E.; Abriola, D.; Capurro, O. A.; Cardona, M. A.; de Barbará, E.; Gollan, F.; Hojman, D.; Pacheco, A. J.; Samsolo, N.; Togneri, M.; Villanueva, D.

    2017-03-01

    The 10Be/9Be ratios in marine sediments samples from the Southern Chile Trench have been measured using accelerator mass spectrometry (AMS). The samples were measured at the TANDAR accelerator, where the discrimination of the 10Be radionuclides was achieved by means of a passive absorber in front of an ionization chamber. This setup along with the high voltage available, provided a complete suppression of the 10B isobar interference. The obtained values for the 10Be concentrations, of the order of 109 atoms/g, are the first 10Be measurements from the Southern Chile Trench and offer an excellent tracer to quantitatively study the recycling of sediments in Andean magmas.

  19. Further Evidence for Medieval Faulting along the Puerto Rico Trench

    Science.gov (United States)

    Atwater, B. F.; Ten Brink, U. S.; Fuentes, Z.; Halley, R. B.; Spiske, M.; Tuttle, M. P.; Wei, Y.

    2013-12-01

    Has the Antilles Subduction Zone produced thrust or outer-rise earthquakes east of Hispaniola? An affirmative answer is suggested by tiered evidence for overwash 120 km south of the Puerto Rico Trench. The evidence comes from Anegada, British Virgin Islands, 200 km east-northeast of San Juan, Puerto Rico. PREVIOUS FINDINGS* suggested that a medieval overwash event had greater geologic effects at Anegada than did a Lisbon(?) event, and that both events outrank recent storms. The medieval overwash, in AD 1200-1450, dislodged brain corals from a reef, moved them as much as 500 m across a shallow subtidal flat, and scattered them as solitary boulders as much as 1000 m inland. Gentler overwash in 1650-1800, called Lisbon(?) because it may represent the 1755 tsunami, laid down a sheet of sand and island-derived shells as much as 1500 m from the north shore. A recent hurricane of category 4 left no durable geologic record other than sandy fans within 40 m of the south shore. NEW FINDINGS reinforce the ranking medieval > Lisbon(?) > storm: (1) The medieval event washed ashore marine shells that the Lisbon(?) event did not. An articulated marine bivalve (Codakia orbicularis), probably deposited live, is part of an overwash fan 400 m inland from Windlass Bight. The shell dates to the same time window as the medieval coral boulders. Additional articulated Codakia shells and a conch shell adjoin the buried base of one of these coral boulders 1500 m south of the fringing reef from which the coral was probably derived. (2) Lisbon(?) overwash used breaches that the medieval event had cut through beach ridges of the north shore. The re-use is marked by sand: on the muddy floor of a partly filled breach, on an organic soil in another such breach, and on a pre-existing fan south of an area of beach-ridge dissection. The buried organic soil, inset into a old breach, is 500 m inland from an area, near Cow Wreck High Point, where young beach ridges may have been breached for the first

  20. Hydrologic behaviour of stormwater infiltration trenches in a central urban area during 2 3/4 years of operation

    DEFF Research Database (Denmark)

    Warnaars, E.; Larsen, A.V.; Jacobsen, P.;

    1999-01-01

    Two infiltration trenches were constructed in a densely built-up area in central Copenhagen and equipped with on-line sensors measuring rain, runoff flow from the connected surfaces and water level in the trenches. The paper describes the field site, the measuring system and the results from an i...

  1. Paleoseismological data from a new trench across the El Camp Fault(Catalan Coastal Ranges, NE Iberian Peninsula

    Directory of Open Access Journals (Sweden)

    K. Boydell

    2003-06-01

    Full Text Available The El Camp Fault (Catalan Coastal Ranges, NE Iberian Peninsula is a slow slipping normal fault whose seismic potential has only recently been recognised. New geomorphic and trench investigations were carried out during a training course across the El Camp Fault at the La Porquerola alluvial fan site. A new trench (trench 8 was dug close to a trench made previously at this site (trench 4. With the aid of two long topographic profiles across the fault scarp we obtained a vertical slip rate ranging between 0.05 and 0.08 mm/yr. At the trench site, two main faults, which can be correlated between trenches 8 and 4, make up the fault zone. Using trench analysis three paleoseismic events were identified, two between 34.000 and 125.000 years BP (events 3 and 2 and another event younger than 13 500 years BP (event 1, which can be correlated, respectively, with events X (50.000- 125.000 years BP, Y (35.000-50.000 years BP and Z (3000-25.000 years BP. The last seismic event at the La Porquerola alluvial fan site is described for the first time, but with some uncertainties.

  2. 78 FR 7385 - Western Pacific Fisheries; Fishing in the Marianas Trench, Pacific Remote Islands, and Rose Atoll...

    Science.gov (United States)

    2013-02-01

    ...; Fishing in the Marianas Trench, Pacific Remote Islands, and Rose Atoll Marine National Monuments AGENCY... Marianas Trench, Pacific Remote Islands, and Rose Atoll Marine National Monuments. DATES: NMFS must receive... record and will generally be posted for public viewing on www.regulations.gov without change....

  3. DOSE ASSESSMENTS FROM THE DISPOSAL OF LOW-ACTIVITY WASTES IN RCRA-C DISPOSAL CELLS

    Science.gov (United States)

    Modeling the long-term performance of the RCRA-C disposal cell and potential doses to off-site receptors is used to derive maximum radionuclide specific concentrations in the wastes that would enable these wastes to be disposed of safely using the RCRA-C disposal cell technology....

  4. NEP processing, operations, and disposal

    Science.gov (United States)

    Stancati, Mike

    Several recent studies by ASAO/NPO staff members at LeRC and by other organizations have highlighted the potential benefits of using Nuclear Electric Propulsion (NEP) as the primary transportation means for some of the proposed missions of the Space Exploration Initiative. These include the potential to reduce initial mass in orbit and Mars transit time. Modular NEP configurations also introduce fully redundant main propulsion to Mars flight systems adding several abort or fall back options not otherwise available. Recent studies have also identified mission operations, such as on orbital assembly, refurbishment, and reactor disposal, as important discriminators for propulsion system evaluation. This study is intended to identify and assess 'end-to-end' operational issues associated with using NEP for transporting crews and cargo between Earth and Mars. We also include some consideration of lunar cargo transfer as well.

  5. Nuclear waste disposal educational forum

    Energy Technology Data Exchange (ETDEWEB)

    1982-10-18

    In keeping with a mandate from the US Congress to provide opportunities for consumer education and information and to seek consumer input on national issues, the Department of Energy's Office of Consumer Affairs held a three-hour educational forum on the proposed nuclear waste disposal legislation. Nearly one hundred representatives of consumer, public interest, civic and environmental organizations were invited to attend. Consumer affairs professionals of utility companies across the country were also invited to attend the forum. The following six papers were presented: historical perspectives; status of legislation (Senate); status of legislation (House of Representatives); impact on the legislation on electric utilities; impact of the legislation on consumers; implementing the legislation. All six papers have been abstracted and indexed for the Energy Data Base.

  6. Deep Borehole Disposal Safety Analysis.

    Energy Technology Data Exchange (ETDEWEB)

    Freeze, Geoffrey A. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Stein, Emily [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Price, Laura L. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); MacKinnon, Robert J. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Tillman, Jack Bruce [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)

    2016-10-01

    This report presents a preliminary safety analysis for the deep borehole disposal (DBD) concept, using a safety case framework. A safety case is an integrated collection of qualitative and quantitative arguments, evidence, and analyses that substantiate the safety, and the level of confidence in the safety, of a geologic repository. This safety case framework for DBD follows the outline of the elements of a safety case, and identifies the types of information that will be required to satisfy these elements. At this very preliminary phase of development, the DBD safety case focuses on the generic feasibility of the DBD concept. It is based on potential system designs, waste forms, engineering, and geologic conditions; however, no specific site or regulatory framework exists. It will progress to a site-specific safety case as the DBD concept advances into a site-specific phase, progressing through consent-based site selection and site investigation and characterization.

  7. ORIGINAL ARTICLES Sharps disposal practices among diabetic ...

    African Journals Online (AJOL)

    waste is generated daily in the form of used needles and syringes. Used sharps are a biomedical hazard as incorrect disposal could lead to needle-stick ... Treatment Guidelines (STG)10 do not provide recommendations on the safe disposal ...

  8. Crystalline and Crystalline International Disposal Activities

    Energy Technology Data Exchange (ETDEWEB)

    Viswanathan, Hari S. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Chu, Shaoping [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Reimus, Paul William [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Makedonska, Nataliia [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Hyman, Jeffrey De' Haven [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Karra, Satish [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dittrich, Timothy M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-12-21

    This report presents the results of work conducted between September 2014 and July 2015 at Los Alamos National Laboratory in the crystalline disposal and crystalline international disposal work packages of the Used Fuel Disposition Campaign (UFDC) for DOE-NE’s Fuel Cycle Research and Development program.

  9. Medications at School: Disposing of Pharmaceutical Waste

    Science.gov (United States)

    Taras, Howard; Haste, Nina M.; Berry, Angela T.; Tran, Jennifer; Singh, Renu F.

    2014-01-01

    Background: This project quantified and categorized medications left unclaimed by students at the end of the school year. It determined the feasibility of a model medication disposal program and assessed school nurses' perceptions of environmentally responsible medication disposal. Methods: At a large urban school district all unclaimed…

  10. 10 CFR 850.32 - Waste disposal.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Waste disposal. 850.32 Section 850.32 Energy DEPARTMENT OF ENERGY CHRONIC BERYLLIUM DISEASE PREVENTION PROGRAM Specific Program Requirements § 850.32 Waste disposal. (a) The responsible employer must control the generation of beryllium-containing waste, and beryllium-contaminated equipment and other...

  11. Medications at School: Disposing of Pharmaceutical Waste

    Science.gov (United States)

    Taras, Howard; Haste, Nina M.; Berry, Angela T.; Tran, Jennifer; Singh, Renu F.

    2014-01-01

    Background: This project quantified and categorized medications left unclaimed by students at the end of the school year. It determined the feasibility of a model medication disposal program and assessed school nurses' perceptions of environmentally responsible medication disposal. Methods: At a large urban school district all unclaimed…

  12. Hydrologic implications of solid-water disposal

    Science.gov (United States)

    Schneider, William Joseph

    1970-01-01

    The disposal of more than 1,400 million pounds of solid wastes in the United States each day is a major problem. This disposal in turn often leads to serious health, esthetic, and environmental problems. Among these is the pollution of vital ground-water resources.

  13. Deep Borehole Disposal as an Alternative Concept to Deep Geological Disposal

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jongyoul; Lee, Minsoo; Choi, Heuijoo; Kim, Kyungsu [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-10-15

    In this paper, the general concept and key technologies for deep borehole disposal of spent fuels or HLW, as an alternative method to the mined geological disposal method, were reviewed. After then an analysis on the distance between boreholes for the disposal of HLW was carried out. Based on the results, a disposal area were calculated approximately and compared with that of mined geological disposal. These results will be used as an input for the analyses of applicability for DBD in Korea. The disposal safety of this system has been demonstrated with underground research laboratory and some advanced countries such as Finland and Sweden are implementing their disposal project on commercial stage. However, if the spent fuels or the high-level radioactive wastes can be disposed of in the depth of 3-5 km and more stable rock formation, it has several advantages. Therefore, as an alternative disposal concept to the mined deep geological disposal concept (DGD), very deep borehole disposal (DBD) technology is under consideration in number of countries in terms of its outstanding safety and cost effectiveness. In this paper, the general concept of deep borehole disposal for spent fuels or high level radioactive wastes was reviewed. And the key technologies, such as drilling technology of large diameter borehole, packaging and emplacement technology, sealing technology and performance/safety analyses technologies, and their challenges in development of deep borehole disposal system were analyzed. Also, very preliminary deep borehole disposal concept including disposal canister concept was developed according to the nuclear environment in Korea.

  14. Conductive Oxides Trench Structures as Hyperbolic Metamaterials in Mid-infrared Range

    DEFF Research Database (Denmark)

    Takayama, Osamu; Shkondin, Evgeniy; Panah, Mohammad Esmail Aryaee;

    ,2]. Moreover plasmonics for mid-infrared offer unique applications such as bio-sensing, thermal imaging and quest for novel materials and structures has been continuing [3]. In this report we show that vertical trench structures made of, for example, aluminum-doped ZnO (AZO) or other transparent conductive...

  15. Large Mode Area Single Trench Fiber for 2 mu m Operation

    DEFF Research Database (Denmark)

    Jain, Deepak; Sahu, Jayanta K.

    2016-01-01

    Performance of single trench fibers has been investigated using finite-element method at 2 mu m wavelength. Numerical investigations show that an effective single mode operation for large effective area between 3000-4000 mu m(2) and 2000-3000 mu m(2) can be achieved at similar to 40 and similar t...

  16. Trench Protection and Principles of Pipe Laying. Instructor Manual. Trainee Manual.

    Science.gov (United States)

    Laborers-AGC Education and Training Fund, Pomfret Center, CT.

    This packet contains the instructor and trainee manuals for a course dealing with trench protection and principles of pipe laying. Part 1 is the instructor guide for an 80-hour course--12 classroom hours and 68 hours of hands-on exercises. Contents are as follows: a course outline; course schedule; equipment list; material and equipment checklist;…

  17. Interim-status groundwater monitoring plan for the 216-B-63 trench

    Energy Technology Data Exchange (ETDEWEB)

    Sweeney, M.D.

    1995-02-09

    This document outlines the groundwater monitoring plan, under RCRA regulations in 40 CFR 265 Subpart F and WAC173-300-400, for the 216-B-63 Trench. This interim status facility is being sampled under detection monitoring criteria and this plan provides current program conditions and requirements.

  18. Paleoseismic investigations along the Peel Boundary Fault : Geological setting, site selection and trenching results

    NARCIS (Netherlands)

    Berg, M. van den; Vanneste, K.; Dost, B.; Lokhorst, A.; Eijk, M. van; Verbeeck, K.

    2002-01-01

    On the basis of a multidisciplinary approach we have unraveled the palaeo-earthquake history of a trenched section across the Peel Boundary Fault. The area shows at present one of the largest contrasts in relative motion on both sides of the fault on the basis of repeated levelling. The geological

  19. Characterization and modeling of atomic layer deposited high-density trench capacitors in silicon

    NARCIS (Netherlands)

    Matters-Kammerer, M.K.; Jinesh, K.B.; Rijks, T.G.S.M.; Roozeboom, F.; Klootwijk, J.H.

    2012-01-01

    A detailed electrical analysis of multiple layer trench capacitors fabricated in silicon with atomic-layer-deposited Al 2O 3 and TiN is presented. It is shown that in situ ozone annealing of the Al 2O 3 layers prior to the TiN electrode deposition significantly improves the electric properties of th

  20. Epimeria abyssalis sp. n. from the Kuril-Kamchatka Trench (Crustacea, Amphipoda, Epimeriidae)

    Science.gov (United States)

    Shimomura, Michitaka; Tomikawa, Ko

    2016-01-01

    Abstract A new deep-sea epimeriid, Epimeria abyssalis is described from the Kuril-Kamchatka Trench, in the northwestern Pacific. This species differs from its congeners in having a short rostrum and a telson with deep and narrow Y-shaped excavation. Epimeria abyssalis is the deepest recorded Epimeria species. A key to the north Pacific species of Epimeria is provided. PMID:28174500

  1. Pulse electroanalysis at gold-gold micro-trench electrodes: chemical signal filtering.

    Science.gov (United States)

    Dale, Sara E C; Marken, Frank

    2013-01-01

    Bipotentiostatic control of micro- and nano-trench sensor systems provides new opportunities for enhancing signals (employing feedback currents) and for improved selectivity (by "chemical filtering"). In this study both phenomena are exploited with a gold-gold micro-trench electrode with ca. 70 microm width and ca. 800 microm trench depth. In "generator-collector mode", feedback current enhancement is demonstrated for the hydroquinone/ benzoquinone redox system. Next, a "modulator-sensor mode" experiment is developed in which one electrode potential is stepped into the negative potential region (employing the normal pulse voltammetry method) to induce an oscillating pH change locally in the micro-trench. The resulting shift in the hydroquinone/benzoquinone reversible potential causes a Faradaic sensor signal (employing chronoamperometry). This method provides a "chemical filter" by selecting pH-sensitive redox processes only, and by showing enhanced sensitivity in the region of low buffer capacity. The results for the chemically reversible hydroquinone/benzoquinone system are contrasted to the detection of the chemically irreversible ammonia oxidation.

  2. Fluid-mechanical Representation of Plate Boundaries - Trench-Ridge System -

    Science.gov (United States)

    Takaku, M.; Fukao, Y.

    2005-12-01

    Seismic tomography models have been used extensively to simulate mantle convection driven by density heterogeneity. Such simulation to date has been unsuccessful to reconcile itself with the most obvious convection-related phenomenon of plate motions. Here we present a theoretical framework for tomography-based convection modeling to include the plates as an integral part of the mantle convection. We model the lithosphere as a highly viscous, incompressible, Newtonian fluid layer and plate boundaries as faults across which tangential velocities are discontinuous. Fluid-mechanical expressions of such faults have their exact analogies in the seismic source representation theory and can be derived by referring to it. We test this idea against the simplest two-dimensional case with only trench and ridge as plate boundaries, and with only subducting slab as mass anomaly. We model ridge (trench) as the horizontal (vertical) tensile fault that comprises of a conjugate pair of 45-degree dip normal (reverse) faults extending over the entire thickness of the surface layer. The system comprises of three elementary convections, slab mass-driven convection, trench fault-driven convection and ridge fault-driven convection. Flow due to the slab excess mass imposes vertical tensile stress on trench, which is released by flow driven by trench faulting. This faulting converts efficiently the vertical tensile stress to the horizontal tensile stress, which can transmit to extreme distances through the surface viscous layer. This horizontal tensile stress is relieved by flow driven by ridge faulting. The three elementary convections are thus coupled through the stress minimum conditions at ridge and trench. The resultant coupled flow is very plate-like in the surface viscous layer. In this system the horizontal surface velocity depends little on the relative distance between the ridge and trench and depends mostly on the excess weight of the subducting slab. The horizontal speed can be

  3. NOAA Deepwater Exploration of the Marianas 2016: Pacific Plate, Mariana Trench, and Mariana Forearc

    Science.gov (United States)

    Fryer, P. B.; Glickson, D.; Kelley, C.; Drazen, J.; Stern, R. J.

    2016-12-01

    Legs 1 and 3 of NOAA Okeanos Explorer EX1605 made 18 (ROV) dives exploring the following: 7 Cretaceous-age, Pacific Plate guyots east of the Trench; 1 small volcano on a Pacific Plate fracture; 3 areas of the inner trench slope; 2 forearc serpentinite mud volcanoes; and 5 forearc fault blocks. The Pacific Plate guyots are heavily manganese encrusted. Part of the rationale for those dives was to make baseline characterization of biota and habitats before potential mining. These guyots had striking diversity and abundance of fauna. Dives on 2 guyots examined high-relief scarps, formed when both down-going plate and edifices fractured outboard of the trench. The scarp on one had Cretaceous reef sequences, whereas the other exposed layers of volcanics. The dive on a small (1 km diameter, 141 m high) volcano on a plate fracture near the trench affirmed that it was relatively young, maybe like Petit-Spot volcanoes east of the Japan Trench. A dive in a canyon west of Guam transitioned from a steep slope of volcanic talus to a gentle sediment-covered slope. The inner trench slope opposite the subducting guyot that exposes reef deposits, revealed similar sequences, suggesting that the guyot is being incorporated into the Mariana forearc. The other inner slope dive traversed talus with fragments of serpentinized peridotite and lies near a chain of forearc serpentinite mud volcanoes. The 2 serpentinite mud volcanoes explored have sedimented, apparently inactive, surfaces, though we recovered a serpentinized peridotite sample from one of them. Dives on the forearc fault blocks attest to dynamic vertical tectonism. Three in the northern forearc show sediment sequences of varying types and textures, all dipping trenchward. Spectacular mid-forearc fault scarps strike east-west, stair-stepping down southward and were traversed on 2 dives. We saw many sequences of indurated sediments. Mapping on Legs 2 and 3 of the expedition showed that these fault scarps are mirrored to the south

  4. Evaluating Transport and Attenuation of Inorganic Contaminants in the Vadose Zone for Aqueous Waste Disposal Sites

    Energy Technology Data Exchange (ETDEWEB)

    Truex, Michael J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Oostrom, Martinus [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Tartakovsky, Guzel D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-09-01

    An approach was developed for evaluating vadose zone transport and attenuation of aqueous wastes containing inorganic (non-volatile) contaminants that were disposed of at the land surface (i.e., directly to the ground in cribs, trenches, tile fields, etc.) and their effect on the underlying groundwater. The approach provides a structured method for estimating transport of contaminants through the vadose zone and the resulting temporal profile of groundwater contaminant concentrations. The intent of the approach is also to provide a means for presenting and explaining the results of the transport analysis in the context of the site-specific waste disposal conditions and site properties, including heterogeneities and other complexities. The document includes considerations related to identifying appropriate monitoring to verify the estimated contaminant transport and associated predictions of groundwater contaminant concentrations. While primarily intended for evaluating contaminant transport under natural attenuation conditions, the approach can also be applied to identify types of, and targets for, mitigation approaches in the vadose zone that would reduce the temporal profile of contaminant concentrations in groundwater, if needed.

  5. Readiness plan, Hanford 300 Area Treated Effluent Disposal Facility: Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    Storm, S.J.

    1994-11-08

    The 300 Area Treated Effluent Disposal Facility (TEDF) is designed for the collection, treatment, and eventual disposal of liquid waste from the 300 Area Process Sewer (PS) system. The PS currently discharges water to the 300 Area Process Trenches. Facilities supported total 54 buildings, including site laboratories, inactive buildings, and support facilities. Effluent discharges to the process sewer from within these facilities include heating, ventilation, and air conditioning systems, heat exchangers, floor drains, sinks, and process equipment. The wastewaters go through treatment processes that include iron coprecipitation, ion exchange and ultraviolet oxidation. The iron coprecipitation process is designed to remove general heavy metals. A series of gravity filters then complete the clarification process by removing suspended solids. Following the iron coprecipitation process is the ion exchange process, where a specific resin is utilized for the removal of mercury. The final main unit operation is the ultraviolet destruction process, which uses high power ultraviolet light and hydrogen peroxide to destroy organic molecules. The objective of this readiness plan is to provide the method by which line management will prepare for a Readiness Assessment (RA) of the TEDF. The self-assessment and RA will assess safety, health, environmental compliance and management readiness of the TEDF. This assessment will provide assurances to both WHC and DOE that the facility is ready to start-up and begin operation.

  6. Mine waste disposal and managements

    Energy Technology Data Exchange (ETDEWEB)

    Cheong, Young Wook; Min, Jeong Sik; Kwon, Kwang Soo; Kim, Ok Hwan; Kim, In Kee; Song, Won Kyong; Lee, Hyun Joo [Korea Institute of Geology Mining and Materials, Taejon (Korea)

    1998-12-01

    Acid Rock Drainage (ARD) is the product formed by the atmospheric oxidation of the relatively common pyrite and pyrrhotite. Waste rock dumps and tailings containing sulfide mineral have been reported at toxic materials producing ARD. Mining in sulphide bearing rock is one of activity which may lead to generation and release of ARD. ARD has had some major detrimental affects on mining areas. The purpose of this study was carried out to develop disposal method for preventing contamination of water and soil environment by waste rocks dump and tailings, which could discharge the acid drainage with high level of metals. Scope of this study was as following: environmental impacts by mine wastes, geochemical characteristics such as metal speciation, acid potential and paste pH of mine wastes, interpretation of occurrence of ARD underneath tailings impoundment, analysis of slope stability of tailings dam etc. The following procedures were used as part of ARD evaluation and prediction to determine the nature and quantities of soluble constituents that may be washed from mine wastes under natural precipitation: analysis of water and mine wastes, Acid-Base accounting, sequential extraction technique and measurement of lime requirement etc. In addition, computer modelling was applied for interpretation of slope stability od tailings dam. (author). 44 refs., 33 tabs., 86 figs.

  7. The disposal of radioactive waste on land

    Energy Technology Data Exchange (ETDEWEB)

    None

    1957-09-01

    A committee of geologists and geophysicists was established by the National Academy of Sciences-National Research Council at the request of the Atomic Energy Commission to consider the possibilities of disposing of high level radioactive wastes in quantity within the continental limits of the United States. The group was charged with assembling the existing geologic information pertinent to disposal, delineating the unanswered problems associated with the disposal schemes proposed, and point out areas of research and development meriting first attention; the committee is to serve as continuing adviser on the geological and geophysical aspects of disposal and the research and development program. The Committee with the cooperation of the Johns Hopkins University organized a conference at Princeton in September 1955. After the Princeton Conference members of the committee inspected disposal installations and made individual studies. Two years consideration of the disposal problems leads to-certain general conclusions. Wastes may be disposed of safely at many sites in the United States but, conversely, there are many large areas in which it is unlikely that disposal sites can be found, for example, the Atlantic Seaboard. Disposal in cavities mined in salt beds and salt domes is suggested as the possibility promising the most practical immediate solution of the problem. In the future the injection of large volumes of dilute liquid waste into porous rock strata at depths in excess of 5,000 feet may become feasible but means of rendering, the waste solutions compatible with the mineral and fluid components of the rock must first be developed. The main difficulties, to the injection method recognized at present are to prevent clogging of pore space as the solutions are pumped into the rock and the prediction or control of the rate and direction of movement.

  8. Disposal of medical waste: a legal perspective.

    Science.gov (United States)

    Du Toit, Karen; Bodenstein, Johannes

    2013-09-03

    The Constitution of the Republic of South Africa provides that everyone has the right to an environment that is not harmful to their health and well-being. The illegal dumping of hazardous waste poses a danger to the environment when pollutants migrate into water sources and ultimately cause widespread infection or toxicity, endangering the health of humans who might become exposed to infection and toxins. To give effect to the Constitution, the safe disposal of hazardous waste is governed by legislation in South Africa. Reports of the illegal disposal of waste suggest a general lack of awareness and training in regard to the safe disposal of medical waste. 

  9. Associate Directorate Environmental Management Infrastructure Plan for Area G and Area L Domes

    Energy Technology Data Exchange (ETDEWEB)

    Stevens, Patrice Ann [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Baumer, Andrew Ronald [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-09-26

    Technical Area 54, at Los Alamos National Laboratory (LANL) is situated in the east-central portion of the Laboratory on the Mesita del Buey between Pajarito Canyon to the south and Cañada del Buey to the north. TA-54 includes four MDAs designated as G, H, J, and L; a waste characterization, container storage, and transfer facility; active TRU waste and MLLW waste storage and low-level waste (LLW) disposal operations at Area G; active hazardous and mixed low-level (MLLW) waste storage operations at Area L; and administrative and support areas. MDA J has previously under-gone closure. Area G is a waste management and disposal area, used for the disposal and storage of radioactive wastes since 1957. Since August 2015, Area G has been in warm standby and provides minimal operations to support safety, compliance, and nitrate salt remediation. Located within Area G, MDA G covers 63-acres. MDA G contains 334 active and inactive waste management units, which include 36 pits, 294 shafts, and 4 trenches. In 1971, Area G began use for the retrievable storage of TRU waste. There are two pits, four trenches and 60 shafts that contain retrievable TRU waste. Thirty-three of the shafts contain TRU waste that may present unique problems for retrieval. In 1986, segregation of MLLW was initiated at Area G for treatment and temporary storage or for off-site disposal. Area G is the only active LLW disposal facility at the Laboratory. Current operations at Area G include storage and characterization of TRU and mixed TRU waste destined for off-site disposal at the Waste Isolation Pilot Plant (WIPP) in southeastern New Mexico and the storage of MLLW destined for off-site treatment and/or disposal. Several above-ground container storage units (CSUs) are currently used for storage of containerized MLLW and/or mixed TRU wastes. These consist of asphalt pads and associated fabric domes or other structures. As defined by the Consent Order, MDA G contains 229 of the 334 subsurface waste

  10. Optimization of Compton Source Performance through Electron Beam Shaping

    Energy Technology Data Exchange (ETDEWEB)

    Malyzhenkov, Alexander [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Yampolsky, Nikolai [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-09-26

    Technical Area 54, at Los Alamos National Laboratory (LANL) is situated in the east-central portion of the Laboratory on the Mesita del Buey between Pajarito Canyon to the south and Cañada del Buey to the north. TA-54 includes four MDAs designated as G, H, J, and L; a waste characterization, container storage, and transfer facility; active TRU waste and MLLW waste storage and low-level waste (LLW) disposal operations at Area G; active hazardous and mixed low-level (MLLW) waste storage operations at Area L; and administrative and support areas. MDA J has previously under-gone closure.Area G is a waste management and disposal area, used for the disposal and storage of radioactive wastes since 1957. Since August 2015, Area G has been in warm standby and provides minimal operations to support safety, compliance, and nitrate salt remediation. Located within Area G, MDA G covers 63-acres. MDA G contains 334 active and inactive waste management units, which include 36 pits, 294 shafts, and 4 trenches. In 1971, Area G began use for the retrievable storage of TRU waste. There are two pits, four trenches and 60 shafts that contain retrievable TRU waste. Thirty-three of the shafts contain TRU waste that may present unique problems for retrieval. In 1986, segregation of MLLW was initiated at Area G for treatment and temporary storage or for off-site disposal. Area G is the only active LLW disposal facility at the Laboratory. Current operations at Area G include storage and characterization of TRU and mixed TRU waste destined for off-site disposal at the Waste Isolation Pilot Plant (WIPP) in southeastern New Mexico and the storage of MLLW destined for off-site treatment and/or disposal. Several above-ground container storage units (CSUs) are currently used for storage of containerized MLLW and/or mixed TRU wastes. These consist of asphalt pads and associated fabric domes or other structures. As defined by the Consent Order, MDA G contains 229 of the 334 subsurface waste

  11. Results of hydrologic research at a low-level radioactive-waste disposal site near Sheffield, Illinois

    Science.gov (United States)

    Ryan, Barbara J.

    1989-01-01

    Ten years of hydrologic research have been conducted by the U.S. Geological Survey at a commercial low-level radioactive-waste disposal site near Sheffield, Illinois. Research included studies of microclimate, evapotranspiration, and tritium release by plants; runoff and land modification; water movement through a trench cover; water and tritium movement in the unsaturated zone; gases in the unsaturated zone; water and tritium movement in the saturated zone; and water chemistry. Implications specific to each research topic and those based on overlapping research topics are summarized as to their potential effect on the selection, characterization, design, operation, and decommissioning processes of future low-level radioactive-waste disposal sites. Unconsolidated deposits at the site are diverse in lithologic character and are spatially and stratigraphically complex. Thickness of these Quaternary deposits ranges from 3 to 27 meters and averages 17 meters. The unconsolidated deposits overlay 140 meters of Pennsylvanian shale, mudstone, siltstone, and coal. Approximately 90,500 cubic meters of waste were buried from August 1967 through August 1978, in 21 trenches that were constructed in glacial materials by using a cut-and-fill process. Trenches generally were constructed below grade and ranged from 11 to 180 meters long, 2.4 to 21 meters wide, and 2.4 to about 7.9 meters deep. Research on microclimate and evapotranspiration at the site was conducted from July 1982 through June 1984. Continuous measurements were made of precipitation, incoming and reflected solar (shortwave) radiation, incoming and emitted terrestrial (longwave) radiation, horizontal windspeed and direction, wet- and dry-bulb air temperature, barometric pressure, soil-heat fluxes, and soil temperature. Soil-moisture content, for this research phase, was measured approximately biweekly. Evapotranspiration rates were estimated by using three techniques--energy budget, aerodynamic profile, and water

  12. Unexpectedly higher metazoan meiofauna abundances in the Kuril-Kamchatka Trench compared to the adjacent abyssal plains

    Science.gov (United States)

    Schmidt, Christina; Martínez Arbizu, Pedro

    2015-01-01

    We studied meiofauna standing stocks and community structure in the Kuril-Kamchatka Trench and its adjacent abyssal plains in the northwestern Pacific Ocean. In general, the Nematoda were dominant (93%) followed by the Copepoda (4%). Nematode abundances ranged from 87% to 96%; those of copepods from 2% to 7%. The most diverse deployment yielded 17 taxa: Acari, Amphipoda, Annelida, Bivalvia, Coelenterata, Copepoda, Cumacea, Gastrotricha, Isopoda, Kinorhyncha, Loricifera, Nematoda, Ostracoda, Priapulida, Tanaidacea, Tantulocarida, and Tardigrada. Nauplii were also present. Generally, the trench slope and the southernmost deployments had the highest abundances (850-1392 individuals/cm2). The results of non-metric multidimensional scaling indicated that these deployments were similar to each other in meiofauna community structure. The southernmost deployments were located in a zone of higher particulate organic carbon (POC) flux (g Corg m-2 yr-1), whereas the trench slope should have low POC flux due to depth attenuation. Also, POC and abundance were significantly correlated in the abyssal plains. This correlation may explain the higher abundances at the southernmost deployments. Lateral transport was also assumed to explain high meiofauna abundances on the trench slope. Abundances were generally higher than expected from model results. ANOSIM revealed significant differences between the trench slope and the northern abyssal plains, between the central abyssal plains and the trench slope, between the trench slope and the southern abyssal plains, between the central and the southern abyssal plains, and between the central and northern deployments. The northern and southern abyssal plains did not differ significantly. In addition, a U-test revealed highly significant differences between the trench-slope and abyssal deployments. The taxa inhabited mostly the upper 0-3 cm of the sediment layer (Nematoda 80-90%; Copepoda 88-100%). The trench-slope and abyssal did not differ

  13. Spent fuel characteristics & disposal considerations

    Energy Technology Data Exchange (ETDEWEB)

    Oversby, V.M.

    1996-06-01

    The fuel used in commercial nuclear power reactors is uranium, generally in the form of an oxide. The gas-cooled reactors developed in England use metallic uranium enclosed in a thin layer of Magnox. Since this fuel must be processed into a more stable form before disposal, we will not consider the characteristics of the Magnox spent fuel. The vast majority of the remaining power reactors in the world use uranium dioxide pellets in Zircaloy cladding as the fuel material. Reactors that are fueled with uranium dioxide generally use water as the moderator. If ordinary water is used, the reactors are called Light Water Reactors (LWR), while if water enriched in the deuterium isotope of hydrogen is used, the reactors are called Heavy Water reactors. The LWRs can be either pressurized reactors (PWR) or boiling water reactors (BWR). Both of these reactor types use uranium that has been enriched in the 235 isotope to about 3.5 to 4% total abundance. There may be minor differences in the details of the spent fuel characteristics for PWRs and BWRs, but for simplicity we will not consider these second-order effects. The Canadian designed reactor (CANDU) that is moderated by heavy water uses natural uranium without enrichment of the 235 isotope as the fuel. These reactors run at higher linear power density than LWRs and produce spent fuel with lower total burn-up than LWRs. Where these difference are important with respect to spent fuel management, we will discuss them. Otherwise, we will concentrate on spent fuel from LWRs.

  14. Marine disposal of radioactive wastes

    Science.gov (United States)

    Woodhead, D. S.

    1980-03-01

    In a general sense, the main attraction of the marine environment as a repository for the wastes generated by human activities lies in the degree of dispersion and dilution which is readily attainable. However, the capacity of the oceans to receive wastes without unacceptable consequences is clearly finite and this is even more true of localized marine environments such as estuaries, coastal waters and semi-enclosed seas. Radionuclides have always been present in the marine environment and marine organisms and humans consuming marine foodstuffs have always been exposed, to some degree, to radiation from this source. The hazard associated with ionizing radiations is dependent upon the absorption of energy from the radiation field within some biological entity. Thus any disposal of radioactive wastes into the marine environment has consequences, the acceptability of which must be assessed in terms of the possible resultant increase in radiation exposure of human and aquatic populations. In the United Kingdom the primary consideration has been and remains the safe-guarding of public health. The control procedures are therefore designed to minimize as far as practicable the degree of human exposure within the overall limits recommended as acceptable by the International Commission on Radiological Protection. There are several approaches through which control could be exercised and the strengths and weaknesses of each are considered. In this review the detailed application of the critical path technique to the control of the discharge into the north-east Irish Sea from the fuel reprocessing plant at Windscale is given as a practical example. It will be further demonstrated that when human exposure is controlled in this way no significant risk attaches to the increased radiation exposure experienced by populations of marine organisms in the area.

  15. DISPOSABLE CANISTER WASTE ACCEPTANCE CRITERIA

    Energy Technology Data Exchange (ETDEWEB)

    R.J. Garrett

    2001-07-30

    The purpose of this calculation is to provide the bases for defining the preclosure limits on radioactive material releases from radioactive waste forms to be received in disposable canisters at the Monitored Geologic Repository (MGR) at Yucca Mountain. Specifically, this calculation will provide the basis for criteria to be included in a forthcoming revision of the Waste Acceptance System Requirements Document (WASRD) that limits releases in terms of non-isotope-specific canister release dose-equivalent source terms. These criteria will be developed for the Department of Energy spent nuclear fuel (DSNF) standard canister, the Multicanister Overpack (MCO), the naval spent fuel canister, the High-Level Waste (HLW) canister, the plutonium can-in-canister, and the large Multipurpose Canister (MPC). The shippers of such canisters will be required to demonstrate that they meet these criteria before the canisters are accepted at the MGR. The Quality Assurance program is applicable to this calculation. The work reported in this document is part of the analysis of DSNF and is performed using procedure AP-3.124, Calculations. The work done for this analysis was evaluated according to procedure QAP-2-0, Control of Activities, which has been superseded by AP-2.21Q, Quality Determinations and Planning for Scientific, Engineering, and Regulatory Compliance Activities. This evaluation determined that such activities are subject to the requirements of DOE/RW/0333P, Quality Assurance Requirements and Description (DOE 2000). This work is also prepared in accordance with the development plan titled Design Basis Event Analyses on DOE SNF and Plutonium Can-In-Canister Waste Forms (CRWMS M&O 1999a) and Technical Work Plan For: Department of Energy Spent Nuclear Fuel Work Packages (CRWMS M&O 2000d). This calculation contains no electronic data applicable to any electronic data management system.

  16. Assessment of alternative disposal concepts

    Energy Technology Data Exchange (ETDEWEB)

    Autio, J.; Saanio, T.; Tolppanen, P. [Saanio and Riekkola Consulting Engineers, Helsinki (Finland); Raiko, H.; Vieno, T. [VTT Energy, Espoo (Finland); Salo, J.P. [Posiva Oy, Helsinki (Finland)

    1996-12-01

    Four alternative repository designs for the disposal of spent nuclear in the Finnish crystalline bedrock were assessed in the study. The alternatives were: (1) the basic KBS-3 design in which copper canisters are emplaced in vertical deposition holes bored in the floors of horizontal tunnels, (2) the KBS-3-2C design with two canisters in a deposition hole, (3) Short Horizontal Holes (SHH) in the side walls of the tunnels, and (4) the Medium Long Holes (MLH) concept in which approximately 25 canisters are emplaced in a horizontal deposition hole about 200 metres in length bored between central and side tunnels. In all the alternatives considered, the thickness of the layer of compacted bentonite between copper canister and bedrock is 35 cm. Two different copper canister designs were also assessed. Technical feasibility and flexibility, post-closure safety and repository cost were assessed for each of the alternative canister and repository designs. On the basis of this assessment it is recommended that further development and studies should focus on the vacuum- or inert gas-filled cast insert type copper canister and the basic KBS-3 type repository design with a single canister in a vertical deposition hole. The KBS-3 design is robust and flexible and provides excellent post-closure safety. The transfer, emplacement and sealing operations are technically uncomplicated. The alternative options assessed do not offer any significant benefits in safety or cost over the basic design, but they are technically more complex and also in some respects more vulnerable to malfunction during the emplacement of canisters and buffer, as well as common mode failures. (60 refs.).

  17. Waste disposal options report. Volume 2

    Energy Technology Data Exchange (ETDEWEB)

    Russell, N.E.; McDonald, T.G.; Banaee, J.; Barnes, C.M.; Fish, L.W.; Losinski, S.J.; Peterson, H.K.; Sterbentz, J.W.; Wenzel, D.R.

    1998-02-01

    Volume 2 contains the following topical sections: estimates of feed and waste volumes, compositions, and properties; evaluation of radionuclide inventory for Zr calcine; evaluation of radionuclide inventory for Al calcine; determination of k{sub eff} for high level waste canisters in various configurations; review of ceramic silicone foam for radioactive waste disposal; epoxides for low-level radioactive waste disposal; evaluation of several neutralization cases in processing calcine and sodium-bearing waste; background information for EFEs, dose rates, watts/canister, and PE-curies; waste disposal options assumptions; update of radiation field definition and thermal generation rates for calcine process packages of various geometries-HKP-26-97; and standard criteria of candidate repositories and environmental regulations for the treatment and disposal of ICPP radioactive mixed wastes.

  18. Concept development for HLW disposal research tunnel

    Energy Technology Data Exchange (ETDEWEB)

    Queon, S. K.; Kim, K. S.; Park, J. H.; Jeo, W. J.; Han, P. S. [KAERI, Taejon (Korea, Republic of)

    2003-10-01

    In order to dispose high-level radioactive waste in a geological formation, it is necessary to assess the safety of a disposal concept by excavating a research tunnel in the same geological formation as the host rock mass. The design concept of a research tunnel depends on the actual disposal concept, repository geometry, experiments to be carried at the tunnel, and geological conditions. In this study, analysis of the characteristics of the disposal research tunnel, which is planned to be constructed at KAERI site, calculation of the influence of basting impact on neighbor facilities, and computer simuation for mechanical stability analysis using a three-dimensional code, FLAC3D, had been carried out to develop the design concept of the research tunnel.

  19. Seismological character of the incoming plate to the Japan Trench and its implication for seismogenic processes

    Science.gov (United States)

    Kodaira, Shuichi; Fujie, Gou; Nakamura, Yasuyuki; Obana, Koichiro; Miura, Seiichi

    2017-04-01

    An interaction between seismological processes in a subduction zone and an incoming lithosphere has been debated; e.g., hydrous minerals and fluid brought to a subduction zone by an incoming lithosphere has been considered as primary factors to control plate coupling, and a large normal fault earthquake in an incoming lithosphere occurred following a great megathrust earthquake in a shallow portion of a subductioin zone. The 1933 Showa-Sanriku earthquake and the 1896 Meiji-Sanriku earthquake are well-known as one of those doublets. Although there have been many geophysical and geological studies in subduction zones to understand an interaction between a subduction zone and an incoming lithosphere, little is known about structures and earthquake activities of an incoming lithosphere. In order to investigate structural characters of the incoming lithosphere to the Japan Trench where the 2011 Tohoku-oki earthquake occurred, JAMSTEC started a new seismological project in which active-source seismic data were acquired along profiles from the ocean basin to the trench through the outer-rise. Results from the active-source seismic profiles to the northern and the middle of the Japan Trench show that reduction of Vp and increase of Vp/Vs in the crust and the uppermost mantle from 150 km seaward of the trench where bend-related normal faults are well developed. In addition to the active-source seismic study, we have been conducting earthquake monitoring in an area from the trench to the outer rise by using OBS network including an ultra-deep OBS deployed at the trench axis. Aftershock activities observed in the incoming lithosphere at the seaward of the fault zone of the 2011 Tohoku-oki earthquake show that some of aftershock clusters extend down to 40 km deep through an area where the Moho reflection is obscure, and most of those earthquakes show normal fault mechanisms. Those observations suggest that bend-related normal faults can be a primal mechanism to bring water

  20. Hotel to Phase out Disposable Articles

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Several hotels in Changsha, Shanghai and Kunming have recently staged a Green Hotel campaign: hotels will not offer disposable toothbrushes, toothpaste, slippers, combs or bottled shampoo and body lotion to their guests unless requested. Meanwhile a Green Hotel Standard has been issued, proscribing "disposable articles, such as toothbrushes, soap, combs and slippers," and stipulating that "textiles, such as bathrobes, towels and pillowslips, in hotel rooms are to be changed strictly at the request of guests,

  1. Cavern/Vault Disposal Concepts and Thermal Calculations for Direct Disposal of 37-PWR Size DPCs

    Energy Technology Data Exchange (ETDEWEB)

    Hardin, Ernest [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Hadgu, Teklu [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Clayton, Daniel James [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)

    2015-03-01

    This report provides two sets of calculations not presented in previous reports on the technical feasibility of spent nuclear fuel (SNF) disposal directly in dual-purpose canisters (DPCs): 1) thermal calculations for reference disposal concepts using larger 37-PWR size DPC-based waste packages, and 2) analysis and thermal calculations for underground vault-type storage and eventual disposal of DPCs. The reader is referred to the earlier reports (Hardin et al. 2011, 2012, 2013; Hardin and Voegele 2013) for contextual information on DPC direct disposal alternatives.

  2. Conformal Deep Trench Coating with both Conducting and InsulatingMaterials

    Energy Technology Data Exchange (ETDEWEB)

    Ji, Lili; Kim, Jung-Kuk; Ji, Qing; Leung, Ka-Ngo; Chen, Ye; Gough, Rick A.

    2006-06-01

    A thin film coating system has been developed for deposition of both conductive and insulating material. The system employs an RF discharge plasma source with four straight RF antennas, which is made of or covered with the deposition material, thus serving simultaneously as a sputtering target. The average deposition rate of the copper thin film can be as high as 500 nm/min when operated in CW mode. Film properties under different plasma conditions have been investigated experimentally. By adjusting RF power, gas pressure, duty factor, and substrate biasing conditions, several thin film coating schemes can be achieved, one of which has been demonstrated to be suitable for conformal deep trench coating. Conformal coating over trenches of high aspect ratio (>6:1) has been demonstrated at both micron and submicron scales.

  3. Mission "in the trenches". A Texas system practices what it calls "co-ministry".

    Science.gov (United States)

    Brother Edward Smink

    2005-01-01

    As responsibility for mission shifts from religious to lay leadership, sponsor-secular partnerships and new models of governance help to ensure that Catholic health care facilities continue the healing ministry of Jesus. By appointing lay mission directors and developing programs that support the work of health care professionals and associates "in the trenches," the sponsors of Catholic health care facilities are embedding particular values and behaviors in their organizations. The miracle of Catholic health care invites women and men of different faith traditions to participate in and contribute to the values, culture, and mission of the Catholic health ministry. Mission "in the trenches" is longer reserved solely for sponsors and religious congregations. By establishing and recognizing the essential services provided by interdisciplinary spiritual care teams and empowering patient caregivers with the knowledge and tools necessary to fulfill their specific responsibilities, the healing presence of God is made known to those who seek our care and observe our actions.

  4. Uniform lateral etching of tungsten in deep trenches utilizing reaction-limited NF3 plasma process

    Science.gov (United States)

    Kofuji, Naoyuki; Mori, Masahito; Nishida, Toshiaki

    2017-06-01

    The reaction-limited etching of tungsten (W) with NF3 plasma was performed in an attempt to achieve the uniform lateral etching of W in a deep trench, a capability required by manufacturing processes for three-dimensional NAND flash memory. Reaction-limited etching was found to be possible at high pressures without ion irradiation. An almost constant etching rate that showed no dependence on NF3 pressure was obtained. The effect of varying the wafer temperature was also examined. A higher wafer temperature reduced the threshold pressure for reaction-limited etching and also increased the etching rate in the reaction-limited region. Therefore, the control of the wafer temperature is crucial to controlling the etching amount by this method. We found that the uniform lateral etching of W was possible even in a deep trench where the F radical concentration was low.

  5. SILICON MICRO-TRENCH ETCHING USING HIGH-DENSITY PLASMA ETCHER

    Institute of Scientific and Technical Information of China (English)

    T.T. Sun; Z.G. Liu; H.C. Yu; M.B. Chen; J.M. Miao

    2005-01-01

    Dry etching of silicon is an essential process step for the fabrication of Microelectromechancal system (MEMS) The AZ7220 positive photo-resist was used as the etching mask and silicon micro-trenches were fabricated with a multiplexed inductively coupled plasma (ICP) etcher.The influence of resist pattern profile, and etch condition on sidewall roughness were investigated detail. The results show that the sidewall roughness of micro-trench depends on profiles of photo-resist pattern, the initial interface between the resist bottom surface and silicon surface heavily. The relationship between roughness and process optimization parameters are presented in the paper. The roughness of the sidewall has been decreased to a 20-50nm with this experiment.

  6. A nanoscale dual-channel trench (DCT) MOSFET for analog/RF applications

    Science.gov (United States)

    Adhikari, Manoj Singh; Singh, Yashvir

    2015-12-01

    In this paper, we propose a dual-channel trench MOSFET (DCT-MOSFET) on SOI for high-frequency small signal analog applications. The gate of device is placed in a trench which creates two n-channels in p-base carrying drain current in parallel. Simultaneous conduction of two-channels provides substantial improvement in performance parameters. Based on two-dimensional simulations, a 60 nm DCT-MOSFET is demonstrated to achieve 92% higher drain current, twofold increase in peak transconductance, 67% rise in transconductance-to-drain current ratio, 47% higher intrinsic voltage gain, 90% improvement in cut-off frequency and 2.1 times higher maximum oscillation frequency as compared to the conventional MOSFET.

  7. Performance of the lithium metal infused trenches in the magnum PSI linear plasma simulator

    Science.gov (United States)

    Fiflis, P.; Morgan, T. W.; Brons, S.; Van Eden, G. G.; Van Den Berg, M. A.; Xu, W.; Curreli, D.; Ruzic, D. N.

    2015-09-01

    The application of liquid metal, especially liquid lithium, as a plasma facing component (PFC) has the capacity to offer a strong alternative to solid PFCs by reducing damage concerns and enhancing plasma performance. The liquid-metal infused trenches (LiMIT) concept is a liquid metal divertor alternative which employs thermoelectric current from either plasma or external heating in tandem with the toroidal field to self-propel liquid lithium through a series of trenches. LiMIT was tested in the linear plasma simulator, Magnum PSI, at heat fluxes of up to 3 MW m-2. Results of these experiments, including velocity and temperature measurements, as well as power handling considerations are discussed, focusing on the 80 shots performed at Magnum scanning magnetic fields and heat fluxes up to ~0.3 T and 3 MW m-2. Comparisons to predictions, both analytical and modelled, are made and show good agreement. Concerns over MHD droplet ejection are additionally addressed.

  8. Fiber-chip grating coupler based on interleaved trenches with directionality exceeding 95.

    Science.gov (United States)

    Alonso-Ramos, C; Cheben, P; Ortega-Moñux, A; Schmid, J H; Xu, D-X; Molina-Fernández, I

    2014-09-15

    We propose a fiber-chip grating coupler that interleaves the standard full and shallow etch trenches in a 220 nm thick silicon layer to provide a directionality upward exceeding 95%. By adjusting the separation between the two sets of trenches, constructive interference is achieved in the upward direction independent of the bottom oxide thickness and without any bottom reflectors, overlays, or customized etch depths. We implement a transverse subwavelength structure in the first two grating periods to minimize back-reflections. The grating coupler has a calculated coupling efficiency of CE~-1.05 dB with a 1 dB bandwidth of 30 nm and minimum feature size of 100 nm, compatible with deep-UV lithography.

  9. Stable Isotopic Evidence for a Pedogenic Origin of Carbonates in Trench 14 near Yucca Mountain, Nevada.

    Science.gov (United States)

    Quade, J; Cerling, T E

    1990-12-14

    Layered carbonate and silica encrust fault fractures exposed in Trench 14 near Yucca Mountain, site of the proposed high-level nuclear waste repository in southern Nevada. Comparison of the stable carbon and oxygen isotopic compositions of the fracture carbonates with those of modern soil carbonates in the area shows that the fracture carbonates are pedogenic in origin and that they likely formed in the presence of vegetation and rainfall typical of a glacial climate. Their isotopic composition differs markedly from that of carbonate associated with nearby springs. The regional water table therefore remained below the level of Trench 14 during the time that the carbonates and silica precipitated, a period probably covering parts of at least the last 300,000 years.

  10. Computational investigation of film cooling from cylindrical and row trenched cooling holes near the combustor endwall

    Directory of Open Access Journals (Sweden)

    Ehsan Kianpour

    2014-11-01

    Full Text Available This study was performed to investigate the effects of cylindrical and row trenched cooling holes with alignment angles of 0° and 90° at blowing ratio of 3.18 on the film cooling performance adjacent to the endwall surface of a combustor simulator. In this research a three-dimensional representation of Pratt and Whitney gas turbine engine was simulated and analyzed with a commercial finite volume package FLUENT 6.2. The analysis has been carried out with Reynolds-Averaged Navier–Stokes turbulence model (RANS on internal cooling passages. This combustor simulator was combined with the interaction of two rows of dilution jets, which were staggered in the streamwise direction and aligned in the spanwise direction. Film cooling was placed along the combustor liner walls. In comparison with the baseline case of cooling holes, the application of a row trenched hole near the endwall surface doubled the performance of film cooling effectiveness.

  11. Assessing the Open Trenches in Screening Railway Ground-Borne Vibrations by Means of Artificial Neural Network

    Directory of Open Access Journals (Sweden)

    Gaetano Di Mino

    2009-01-01

    This paper deals with the study of the effect, in terms of reduction of vertical and horizontal displacements and velocities, of the open trenches. 2D FEM simulations have been performed and several open trench configurations have been analysed varying the main geometric features such as width and depth, distance from the rail, thickness of the soil layer over the rigid bedrock, type of the ground, ratio between the depth of the trench, and the thickness of the soil layer. For quantifying the influence of the above specified parameters in reducing ground-borne vibrations an analysis using artificial neural networks (ANNs has been carried out. Results show that among the geometric parameters the role of the depth of the trench is very significant; however the influence of the depth must be also evaluated in relation to the thickness of the soil layer.

  12. Sun Illuminated Color Image of the 150 meter grid of the Puerto Rico Trench (SUNILLUM.TIF)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Geologic features in the Puerto Rico trench are remotely sensed, monitored, collected, studied, and analyzed. This data set was colorized by depth and converted to...

  13. Sun Illuminated Color Image of the 150 meter grid of the Puerto Rico Trench (SUNILLUM.TIF)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Geologic features in the Puerto Rico trench are remotely sensed, monitored, collected, studied, and analyzed. This data set was colorized by depth and converted to...

  14. Expanded public notice: Washington State notice of intent for corrective action management unit, Hanford Environmental Restoration Disposal

    Energy Technology Data Exchange (ETDEWEB)

    1994-01-01

    This document is to serve notice of the intent to operate an Environmental Restoration Disposal Facility (ERDF), adjacent to the 200 West Area of the Hanford Facility, Richland, Washington, as a Corrective Action Management Unit (CAMU), in accordance with 40 Code of Federal Regulation (CFR) 264.552. The ERDF CAMU will serve as a management unit for the majority of waste (primarily soil) excavated during remediation of waste management sites on the Hanford Facility. Only waste that originates from the Hanford Facility can be accepted in this ERDF CAMU. The waste is expected to consist of dangerous waste, radioactive waste, and mixed waste. Mixed waste contains radioactive and dangerous components. The primary features of the ERDF could include the following: one or more trenches, rail and tractor/trailer container handling capability, railroads, an inventory control system, a decontamination building, and operational offices.

  15. Surface characterization of InP trenches embedded in oxide using scanning probe microscopy

    Science.gov (United States)

    Mannarino, Manuel; Chintala, Ravi; Moussa, Alain; Merckling, Clement; Eyben, Pierre; Paredis, Kristof; Vandervorst, Wilfried

    2015-12-01

    Metrology for structural and electrical analyses at device level has been identified as one of the major challenges to be resolved for the sub-14 nm technology nodes. In these advanced nodes, new high mobility semiconductors, such as III-V compounds, are grown in narrow trenches on a Si substrate. Probing the nature of the defects, the defect density, and the role of processing steps on the surface of such structures are prime metrology requirements. In order to enable defect analysis on a (III-V) surface, a proper sample preparation for oxide removal is of primary importance. In this work, the effectiveness of different chemical cleanings and thermal annealing procedures is investigated on both blanket InP and oxide embedded InP trenches by means of scanning probe microscopy techniques. It is found that the most effective approach is a combination of an HCl-based chemical cleaning combined with a low-temperature thermal annealing leading to an oxide free surface with atomically flat areas. Scanning tunneling microscopy (STM) has been the preferred method for such investigations on blanket films due to its intrinsic sub-nm spatial resolution. However, its application on oxide embedded structures is non-trivial. To perform STM on the trenches of interest (generally <20 nm wide), we propose a combination of non-contact atomic force microscopy and STM using the same conductive atomic force microscopy tip Our results prove that with these procedures, it is possible to perform STM in narrow InP trenches showing stacking faults and surface reconstruction. Significant differences in terms of roughness and terrace formation are also observed between the blanket and the oxide embedded InP.

  16. The Second Las Cruces Trench Experiment: Experimental Results and Two-Dimensional Flow Predictions

    Science.gov (United States)

    Hills, R. G.; Wierenga, P. J.; Hudson, D. B.; Kirkland, M. R.

    1991-10-01

    As part of a comprehensive field study designed to provide data to test stochastic and deterministic models of water flow and contaminant transport in the vadose zone, several trench experiments were performed in the semiarid region of southern New Mexico. The first trench experiment is discussed by Wierenga et al. (this issue). During the second trench experiment, a 1.2 m wide by 12 m long area on the north side of and parallel to a 26.4 m long by 4.8 m wide by 6m deep trench was irrigated with water containing tracers using a carefully controlled drip irrigation system. The irrigated area was heavily instrumented with tensiometers and neutron probe access tubes to monitor water movement, and with suction samplers to monitor solute transport. Water containing tritium and bromide was. applied during the first 11.5 days of the study. Thereafter, water was applied without tracers for an additional 64 days. Both water movement and tracer movement were monitored in the subsoil during infiltration and redistribution. The experimental results indicate that water and bromide moved fairly uniformly during infiltration and the bromide moved ahead of the tritium due to anion exclusion during redistribution. Comparisons between measurements and predictions made with a two-dimensional model show qualitative agreement for two of the three water content measurement planes. Model predictions of tritium and bromide transport were not as satisfactory. Measurements of both tritium and bromide show localized areas of high relative concentrations and a large downward motion of bromide relative to tritium during redistribution. While the simple deterministic model does show larger downward motions for bromide than for tritium during redistribution, it does not predict the high concentrations of solute observed during infiltration, nor can it predict the heterogeneous behavior observed for tritium during infiltration and for bromide during redistribution.

  17. Response of a pipeline to ground movements caused by trenching in compressible alluvium

    Science.gov (United States)

    Carder, D. R.; Taylor, M. E.; Pocock, R. G.

    Disturbance of the ground due to work on buried services, such as the renewal, replacement or construction of deep sewers, is likely to cause differential ground movements in the vicinity. This may be a factor contributing to failure in nearby service pipelines such as drainage, gas and water mains. The response of an instrumented shallow buried pipeline to ground movements caused by adjacent deep trenching in a compressible alluvium is described.

  18. Evidence of paleoearthquakes from trench investigations along Pinjore Garden fault in Pinjore Dun, NW Himalaya

    Indian Academy of Sciences (India)

    Javed N Malik; George Mathew

    2005-08-01

    The Pinjore Garden Fault (PGF) striking NNW–SSE is now considered one of the active faults displacing the younger Quaternary surfaces in the piggyback basin of Pinjore Dun. This has displaced the older Kalka and Pinjore surfaces, along with the other younger surfaces giving rise to WSW and SW-facing fault scarps with heights ranging from 2 to 16m. The PGF represents a younger branch of the Main Boundary Thrust (MBT) system. An ∼4m wide trench excavated across the PGF has revealed displacement of younger Quaternary deposits along a low angle thrust fault. Either side of the trench-walls reveals contrasting slip-related deformation of lithounits. The northern wall shows displacement of lithounits along a low-angle thrust fault, while the southern wall shows well-developed fault-related folding of thick sand unit. The sudden change in the deformational features on the southern wall is an evidence of the changing fault geometry within a short distance. Out of five prominent lithounits identified in the trench, the lower four units show displacement along a single fault. The basal unit ‘A’ shows maximum displacement of about To = 2.85 m, unit B = 1.8m and unit C = 1.45 m. The displacement measured between the sedimentary units and retro-deformation of trench log suggests that at least two earthquake events have occurred along the PGF. The units A and D mark the event horizons. Considering the average amount of displacement during one single event (2m) and the minimum length of the fault trace (∼45 km), the behaviour of PGF seems similar to that of the Himalayan Frontal Fault (HFF) and appears capable of producing large magnitude earthquakes.

  19. Varying mechanical coupling along the Andean margin: Implications for trench curvature, shortening and topography

    Science.gov (United States)

    Iaffaldano, G.; Di Giuseppe, E.; Corbi, F.; Funiciello, F.; Faccenna, C.; Bunge, H.-P.

    2012-03-01

    Convergent margins often exhibit spatial and temporal correlations between trench curvature, overriding plate shortening and topography uplift that provide insights into the dynamics of subduction. The Andean system, where the Nazca plate plunges beneath continental South America, is commonly regarded as the archetype of this class of tectonics systems. There is distinctive evidence that the degree of mechanical coupling between converging plates, i.e. the amount of resistive force mutually transmitted in the direction opposite to their motions, may be at the present-day significantly higher along the central Andean margin compared to the northern and southern limbs. However quantitative estimates of such resistance are still missing and would be desirable. Here we present laboratory models of subduction performed to investigate quantitatively how strong lateral coupling variations need to be to result in trench curvature, tectonic shortening and distribution of topography comparable to estimates from the Andean margin. The analogue of a two-layers Newtonian lithosphere/upper mantle system is established in a silicone putty/glucose syrup tank-model where lateral coupling variations along the interface between subducting and overriding plates are pre-imposed. Despite the simplicity of our setup, we estimate that coupling in the central margin as large as 20% of the driving force is sufficient to significantly inhibit the ability of the experimental overriding plate to slide above the subducting one. As a consequence, the central margin deforms and shortens more than elsewhere while the trench remains stationary, as opposed to the advancing lateral limbs. This causes the margin to evolve into a peculiar shape similar to the present-day trench of the Andean system.

  20. High rates of microbial carbon turnover in sediments in the deepest oceanic trench on Earth

    DEFF Research Database (Denmark)

    Glud, Ronnie N.; Wenzhöfer, Frank; Middelboe, Mathias

    2013-01-01

    Microbes control the decomposition of organic matter in marine sediments. Decomposition, in turn, contributes to oceanic nutrient regeneration and influences the preservation of organic carbon(1). Generally, rates of benthic decomposition decline with increasing water depth, although given the vast...... deposition in the trench. We conclude that the elevated deposition of organic matter at Challenger Deep maintains intensified microbial activity at the extreme pressures that characterize this environment....

  1. High efficiency perfluorocyclobutyl air-trench splitters for use in compact ring resonators

    Science.gov (United States)

    Rahmanian, Nazli

    Planar lightwave circuits with higher integration, lower cost, and added functionality can reduce costs in optical network components. To facilitate large scale integration of planar lightwave circuits the size of their fundamental building blocks such as splitters and bends needs to be reduced. In this dissertation compact air trench splitters are demonstrated in perfluorocyclobutyl (PFCB) polymers. To realize these high efficiency splitters we have developed a very high aspect ratio (18:1) anisotropic PFCB etch for submicron features using a CO/O2 etch chemistry in an inductively coupled plasma reactive ion etcher (ICP-RIE). A low loss of 0.45 dB/splitter (90.1% efficiency) has been measured on splitters fabricated on silicon substrates. The etch process was successfully transferred to Ultem substrates to reduce the effects of the coefficient of thermal expansion (CTE) mismatch between PFCB and silicon. An ultra-compact ring resonator was demonstrated in PFCB with a splitting ratio of 85% to 15% (85-15) air-trench splitters and air-trench bends. The ring resonator size is only 70 mum x 100 mum. Measurements show a 7.2 nm free spectral range (FSR) in agreement with 2-dimensional finite difference time domain (2-D FDTD) simulation results. A 1.8 nm full width at half maximum (FWHM) and ˜10 dB insertion loss for the drop port was measured. The source of loss is explained with comparison to analytical calculations and measurement results. The ring resonator size is reduced by a factor of 1700 compared to a traditionally designed RR in the same material system due to the size reduction provided by the air-trench splitters and bends.

  2. The Challenges of Waste Disposal in a Secondary City: Calabar ...

    African Journals Online (AJOL)

    The Challenges of Waste Disposal in a Secondary City: Calabar Metropolis – Cross ... Waste disposal is a major aspect in environmental preservation for healthy living. ... irregular collection and evacuation of waste materials and lack of funds. ... agencies to partner in waste disposal, create awareness on waste disposal, ...

  3. 36 CFR 228.57 - Types of disposal.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 2 2010-07-01 2010-07-01 false Types of disposal. 228.57... Disposal of Mineral Materials Types and Methods of Disposal § 228.57 Types of disposal. Except as provided... qualified bidder after formal advertising and other appropriate public notice; (b) Sale by...

  4. 36 CFR 13.1604 - Solid waste disposal.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Solid waste disposal. 13.1604... Solid waste disposal. (a) A solid waste disposal site may accept non-National Park Service solid waste generated within the boundaries of the park area. (b) A solid waste disposal site may be located within...

  5. 36 CFR 13.1008 - Solid waste disposal.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Solid waste disposal. 13.1008... § 13.1008 Solid waste disposal. (a) A solid waste disposal site may accept non-National Park Service solid waste generated within the boundaries of the park area. (b) A solid waste disposal site may...

  6. 36 CFR 13.1118 - Solid waste disposal.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Solid waste disposal. 13.1118... Provisions § 13.1118 Solid waste disposal. (a) A solid waste disposal site may accept non-National Park Service solid waste generated within the boundaries of the park area. (b) A solid waste disposal site...

  7. 36 CFR 13.1912 - Solid waste disposal.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Solid waste disposal. 13.1912....1912 Solid waste disposal. (a) A solid waste disposal site may accept non-National Park Service solid waste generated within the boundaries of the park area. (b) A solid waste disposal site may be...

  8. Slab Stagnation and Buckling in the Mantle Transition Zone: Petrology, Rheology, and the Geodynamics of Trench Migration

    Science.gov (United States)

    Bina, C. R.; Čížková, H.

    2015-12-01

    Recent work indicates that subducting slabs may exhibit buckling instabilities and consequent folding behavior in the mantle transition zone for various dynamical parameters, accompanied by temporal variations in dip angle, plate velocity, and trench retreat. Governing parameters include both viscous (rheological) and buoyancy (thermo-petrological) forces. 2D numerical experiments show that many parameter sets lead to slab deflection at the base of the transition zone, typically accompanied by quasi-periodic oscillations in largely anticorrelated plate and rollback velocities, resulting in undulating stagnant slabs as buckle folds accumulate subhorizontally atop the lower mantle. Slab petrology, of mantle phase transitions and hydrated crust, is a dominant factor in this process (Čížková and Bina, 2013). For terrestrial parameter sets, trench retreat is found to be nearly ubiquitous and trench advance quite rare, largely due to rheological and ridge-push effects. Recently updated analyses of global plate motions indicate that significant trench advance is also rare on Earth, being largely restricted to the Izu-Bonin arc (Matthews et al., 2013). Thus, we explore conditions necessary for terrestrial trench advance through dynamical models involving the unusual geometry of the Philippine Sea region. Our 2D modeling of such geometries, in which distal subduction of the overriding plate overprints an opposed slab-pull force on the usual ridge-push at the trench, yields persistent trench advance interrupted by episodes of back-arc extension, demonstrating that trench advance can occur for terrestrial rheologies in such special geometries (Čížková and Bina, 2015).

  9. Trench foot--a study in military-medical responsiveness in the Great War, 1914-1918.

    Science.gov (United States)

    Haller, J S

    1990-06-01

    Along the nearly 15,000 miles of trenches on the western front in the Great War of 1914-1918, a condition known as "trench foot" caused serious attrition among the fighting troops and resulted in swollen limbs, impaired sensory nerves, inflammation, and even loss of tissue through gangrene. Physicians, sanitarians, and military officers explored numerous theories regarding etiology and treatment before focusing on a combined regimen of common-sense hygiene and strict military discipline.

  10. 沟槽型MOSFET的发展%Development of Trench MOSFET

    Institute of Scientific and Technical Information of China (English)

    王翠霞; 范学峰; 许维胜; 谢福渊

    2009-01-01

    Trench MOSFET shows two advantages while replacing the rectifier diode in the power converter: it can be controlled flexibly by the PWM driver to provide the desired energy for different loads ; it greatly reduces the conduction loss and the conduction resistance is low.In this paper, the newly devoloped configurations of Trench MOSFET are introduced, which includes thick oxide MOSFET, Resurf stepped oxide MOSFET, Trench MOSFET integrated Schottky diode. The mechanism and the performance of them are also discussed.%在功率变换器中沟槽型MOSFET取代功率二极管传递能量有两个优点:可以用PWM驱动电路灵活地控制MOSFET为不同的负载提供所需的能量;导通电阻低,能耗小.文章介绍了新研究出来的厚栅氧MOSFET,RSO MOSFET,集成肖特基二极管的沟槽型MOSFET,并对它们的机理和性能进行了阐述和分析.

  11. Performance Analysis of Trench Power MOSFETs in High-Frequency Synchronous Buck Converter Applications

    Directory of Open Access Journals (Sweden)

    Yali Xiong

    2008-01-01

    Full Text Available This paper investigates the performance perspectives and theoretical limitations of trench power MOSFETs in synchronous rectifier buck converters operating in the MHz frequency range. Several trench MOSFET technologies are studied using a mixed-mode device/circuit modeling approach. Individual power loss contributions from the control and synchronous MOSFETs, and their dependence on switching frequency between 500 kHz and 5 MHz are discussed in detail. It is observed that the conduction loss contribution decreases from 40% to 4% while the switching loss contribution increases from 60% to 96% as the switching frequency increases from 500 KHz to 5 MHz. Beyond 1 MHz frequency there is no obvious benefit to increase the die size of either SyncFET or CtrlFET. The RDS(ON×QG figure of merit (FOM still correlates well to the overall converter efficiency in the MHz frequency range. The efficiency of the hard switching buck topology is limited to 80% at 2 MHz and 65% at 5 MHz even with the most advanced trench MOSFET technologies.

  12. Plasma-assisted atomic layer deposition of conformal Pt films in high aspect ratio trenches

    Science.gov (United States)

    Erkens, I. J. M.; Verheijen, M. A.; Knoops, H. C. M.; Keuning, W.; Roozeboom, F.; Kessels, W. M. M.

    2017-02-01

    To date, conventional thermal atomic layer deposition (ALD) has been the method of choice to deposit high-quality Pt thin films grown typically from (MeCp)PtMe3 vapor and O2 gas at 300 °C. Plasma-assisted ALD of Pt using O2 plasma can offer several advantages over thermal ALD, such as faster nucleation and deposition at lower temperatures. In this work, it is demonstrated that plasma-assisted ALD at 300 °C also allows for the deposition of highly conformal Pt films in trenches with high aspect ratio ranging from 3 to 34. Scanning electron microscopy inspection revealed that the conformality of the deposited Pt films was 100% in trenches with aspect ratio (AR) up to 34. These results were corroborated by high-precision layer thickness measurements by transmission electron microscopy for trenches with an aspect ratio of 22. The role of the surface recombination of O-radicals and the contribution of thermal ALD reactions is discussed.

  13. Rapid trench initiated recrystallization and stagnation in narrow Cu interconnect lines

    Energy Technology Data Exchange (ETDEWEB)

    O' Brien, Brendan B.; Rizzolo, Michael; Prestowitz, Luke C.; Dunn, Kathleen A., E-mail: kdunn1@sunypoly.edu [Colleges of Nanoscale Science and Engineering, SUNY Polytechnic Institute, Albany, New York 12203 (United States)

    2015-10-26

    Understanding and ultimately controlling the self-annealing of Cu in narrow interconnect lines has remained a top priority in order to continue down-scaling of back-end of the line interconnects. Recently, it was hypothesized that a bottom-up microstructural transformation process in narrow interconnect features competes with the surface-initiated overburden transformation. Here, a set of transmission electron microscopy images which captures the grain coarsening process in 48 nm lines in a time resolved manner is presented, supporting such a process. Grain size measurements taken from these images have demonstrated that the Cu microstructural transformation in 48 nm interconnect lines stagnates after only 1.5 h at room temperature. This stubborn metastable structure remains stagnant, even after aggressive elevated temperature anneals, suggesting that a limited internal energy source such as dislocation content is driving the transformation. As indicated by the extremely low defect density found in 48 nm trenches, a rapid recrystallization process driven by annihilation of defects in the trenches appears to give way to a metastable microstructure in the trenches.

  14. Coseismic seafloor deformation in the trench region during the Mw8.8 Maule megathrust earthquake

    Science.gov (United States)

    Maksymowicz, A.; Chadwell, C. D.; Ruiz, J.; Tréhu, A. M.; Contreras-Reyes, E.; Weinrebe, W.; Díaz-Naveas, J.; Gibson, J. C.; Lonsdale, P.; Tryon, M. D.

    2017-04-01

    The Mw 8.8 megathrust earthquake that occurred on 27 February 2010 offshore the Maule region of central Chile triggered a destructive tsunami. Whether the earthquake rupture extended to the shallow part of the plate boundary near the trench remains controversial. The up-dip limit of rupture during large subduction zone earthquakes has important implications for tsunami generation and for the rheological behavior of the sedimentary prism in accretionary margins. However, in general, the slip models derived from tsunami wave modeling and seismological data are poorly constrained by direct seafloor geodetic observations. We difference swath bathymetric data acquired across the trench in 2008, 2011 and 2012 and find ~3-5 m of uplift of the seafloor landward of the deformation front, at the eastern edge of the trench. Modeling suggests this is compatible with slip extending seaward, at least, to within ~6 km of the deformation front. After the Mw 9.0 Tohoku-oki earthquake, this result for the Maule earthquake represents only the second time that repeated bathymetric data has been used to detect the deformation following megathrust earthquakes, providing methodological guidelines for this relatively inexpensive way of obtaining seafloor geodetic data across subduction zone.

  15. Demonstration of integrated polarization rotator based on an asymmetric silicon waveguide with a trench

    Science.gov (United States)

    Kim, Yudeuk; Kim, Dong Wook; Lee, Moon-Hyeok; Lee, Min Hee; Yoo, Dong Eun; Kim, Ki Nam; Jeon, Sang Chul; Kim, Kyong Hon

    2016-09-01

    An integrated polarization rotator is demonstrated experimentally by forming a strip waveguide with an asymmetric trench on a silicon-on-insulator wafer. The trench is located asymmetrically in the strip waveguide. It induces the evolution of an orthogonal polarization mode upon a linearly polarized beam input, and thus causes polarization rotation. The device is fabricated using a conventional complementary metal oxide semiconductor process with a single dry etching step. The fabricated device shows a maximum transverse electric (TE)-to-transverse magnetic (TM) polarization conversion efficiency of 21.3 dB and an insertion loss of -0.95 dB at a 1550 nm wavelength with a device length of 67 μm. The device exhibits a polarization conversion efficiency and insertion loss of 21.1 dB and -2.12 dB, respectively, for the TM-to-TE polarization conversion. The optimum parameters for the waveguide size and trench size are investigated by performing numerical simulations, and by demonstrating experimental fabrication and measurement.

  16. Forearc slope deformation above the Japan Trench megathrust: Implications for subduction erosion

    Science.gov (United States)

    Boston, Brian; Moore, Gregory F.; Nakamura, Yasuyuki; Kodaira, Shuichi

    2017-03-01

    Subduction erosion is a commonly invoked model that is used to explain the tectonic subsidence of the Japan Trench forearc slope, although other models have explained the morphology and history of the margin. New multichannel seismic reflection and bathymetric data collected after the 2011 Tohoku earthquake provide the opportunity to investigate the detailed structure of the overriding plate near the earthquake epicenter and obtain new constraints on tectonic models. We use regional-residual separation of the local bathymetry to constrain fault scarp extents and local landward-dipping forearc basins. Seismic images of these basins clearly show landward-dipping horizons in the shallow section. The strata in these basins imply a different mechanism for formation than the surrounding forearc slope, and we propose that these basins formed from local uplift. A regional basal unconformity mapped ∼150 km along-trench has highly variable relief, indicating that forearc slope subsidence occurs at multiple wavelengths in response to multiple different sources. We characterize the upper to middle slope transition and propose that this region may be the landward limit of major subduction erosion and also the main region for large mass wasting. Normal faults found in this setting have maximum lengths of ∼20 km, limiting their role in margin processes. Our results place constraints on the extent of major subduction erosion at the Japan Trench margin, and indicate that subduction erosion should be revisited as the sole model of formation to include additional tectonic processes.

  17. Evaluation on heating energy saving of double crude oil pipelines laid in one trench

    Energy Technology Data Exchange (ETDEWEB)

    Bo Yu; Yue Shi; Xin Liu; Jinjun Zhang [China University of Petroleum (Beijing), Beijing (China). Beijing Key Lab. of Urban Oil and Gas Distribution Technology; Jinjia Wei [Xi' an Jiaotong University, Xi' an (China). State Key Lab. of Multiphase Flow in Power Engineering

    2009-12-19

    Laying two hot pipelines in one trench is probably an effective way not only to minimize environmental damage but also to bring tremendous economic and social benefits. In this paper heating energy saving evaluations of operation on two hot crude oil pipelines laid in one trench as compared to single pipeline system are performed. In the calculations a Delaunay triangulation method is used to generate the grids of the soil domain automatically with denser meshes near the pipelines. A structural grid generation in polar coordinates is applied to the steel pipe wall and corrosion protective covering. A finite volume method combined with a finite difference scheme is used to discretized the governing equations. The discretized equations are solved by a Gauss-Seidel method. The thermal impact between two hot crude oil pipelines laid in one trench under four operating conditions are numerically analyzed. Through numerical simulations the outlet temperatures for safe pipelining hot crude oils of double pipelines can be obtained as well as heating energy consumption. Comparison between double-pipeline system and single pipeline system is made to evaluate the economy of different operating schemes. It is found that applying the prospective new technology can dramatically lower the outlet temperatures of the two pipelines and it would save a lot of heating energy. (author)

  18. Plastic pollution of the Kuril-Kamchatka Trench area (NW pacific)

    Science.gov (United States)

    Fischer, Viola; Elsner, Nikolaus O.; Brenke, Nils; Schwabe, Enrico; Brandt, Angelika

    2015-01-01

    During the German-Russian expedition KuramBio (Kuril-Kamchatka Biodiversity Studies) to the northwest Pacific Kuril-Kamchatka Trench and its adjacent abyssal plain, we found several kinds and sizes of plastic debris ranging from fishing nets and packaging to microplastic in the sediment of the deep-sea floor. Microplastics were ubiquitous in the smaller fractions of the box corer samples from every station from depths between 4869 and 5766 m. They were found on the abyssal plain and in the sediments of the trench slope on both sides. The amount of microplastics differed between the stations, with lowest concentration of 60 pieces per m2 and highest concentrations of more than 2000 pieces per m2. Around 75% of the microplastics (defined here as particles marine fauna (Zenkevich, 1963). Yet we can only guess how these microplastics accumulated in the deep sea of the Kuril-Kamchatka Trench area and what consequences the microplastic itself and its adsorbed chemicals will have on this very special and rich deep-sea fauna. But we herewith present an evaluation of the different kinds of plastic debris we found, as a documentation of human impact into the deep sea of this region of the Northwest Pacific.

  19. Characterization and Comparison of Planar and Trench Silicon Carbide (SiC) Power MOSFETs

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Zhiqiang [ORNL; Chinthavali, Madhu Sudhan [ORNL; Campbell, Steven L [ORNL

    2016-01-01

    This paper presents a comprehensive evaluation and experimental comparison of silicon carbide power MOSFETs through double pulse test. First, a universal hardware platform is designed and developed to test power semiconductor devices with various device packages and measuring requirements. Using the developed platform, the static characteristics and switching performance of the two types of SiC MOSFETs (one planar and one trench type) are evaluated under different case temperatures from 25 oC to 175 oC. Based on the evaluation data, a comparison of both SiC MOSFETs is conducted in terms of their on-state resistance, switching loss, and temperature dependent behavior. It is found that the latest trench SiC MOSFETs present similar switching loss while much lower conduction loss compared to existing commercial planar SiC MOSFETs. Moreover, the trench devices show a nearly temperature independent switching loss, which is beneficial to suppress the potential thermal runaway issue under high temperature continuous operation.

  20. Laser directed lithography of asymmetric graphene ribbons on a polydimethylsiloxane trench structure.

    Science.gov (United States)

    Tian, He; Yang, Yi; Xie, Dan; Ren, Tian-Ling; Shu, Yi; Sun, Hui; Zhou, Chang-Jian; Liu, Xuan; Tao, Lu-Qi; Ge, Jie; Zhang, Cang-Hai; Zhang, Yuegang

    2013-05-14

    Recently, manipulating heat transport by asymmetric graphene ribbons has received significant attention, in which phonons in the carbon lattice are used to carry energy. In addition to heat control, asymmetric graphene ribbons might also have broad applications in renewable energy engineering, such as thermoelectric energy harvesting. Here, we transfer a single sheet of graphene over a 5 μm trench of polydimethylsiloxane (PDMS) structure. By using a laser (1.77 mW, 1 μm diameter spot size, 517 nm wavelength) focusing on one side of the suspended graphene, a triangular shaped graphene ribbon is obtained. As the graphene has a negative thermal expansion coefficient, local laser heating could make the affected graphene area shrink and eventually break. Theoretical calculation shows that the 1.77 mW laser could create a local hot spot as high as 1462.5 °C, which could induce an asymmetric shape structure. We also find the temperature coefficient (-13.06 cm(-1) mW) of suspended graphene on PDMS trench substrate is ten times higher than that reported on SiO2/Si trench substrate. Collectively, our results raise the exciting prospect that the realization of graphene with asymmetric shape on thermally insulating substrate is technologically feasible, which may open up important applications in thermal circuits and thermal management.

  1. Disposal frequencies of selected recyclable wastes in Dar es Salaam.

    Science.gov (United States)

    Mgaya, Prosper; Nondek, Lubomir

    2004-01-01

    A statistical survey of households based upon questionnaires distributed via primary schools has been carried out in five wards of Dar es Salaam, Tanzania, to estimate disposal frequencies (number of items disposed per week) for newsprint, metal cans, glass and plastic containers and plastic shopping bags. Plastic shopping bags are disposed most frequently while glass containers are disposed least frequently. The statistical distribution of disposal frequencies, which seems to be influenced by household income, is well described by Poisson distribution. Disposal frequencies are mutually correlated at 95% level of probability despite the differences in disposal patterns of individual households.

  2. Contrast of Subsea Pipeline Trenching Methods%海底管道挖沟方法的选择

    Institute of Scientific and Technical Information of China (English)

    杜喜军; 赵杰; 王艳涛; 刘坤

    2015-01-01

    Trenching is a common method of protection for subsea oil and gas transmission pipeline .In this paper, the major subsea pipeline trenching method and trenching equipments were summarized , and the advantages and disadvantages of all kinds of trenching methods were analyzed .According to specific project , water depth, geological conditions and depth of trench in dif-ferent pipe section were analyzed in this paper .The corresponding trench methods were adopted in different sections , thus ensu-ring the project progress , improving the efficiency , saving the cost and meeting the reserve requirements .%对海底油气输送管道进行挖沟填埋是一种常用的保护方法。文中综述了海底管道主要的挖沟方法及其适用的挖沟设备,分析了各种挖沟方法的优缺点及其适用条件。通过具体工程案例分析了不同管段海域水深、地质条件、挖沟深度等实际情况,在不同的管段采取相应的挖沟方法,选用合理挖沟机械;保证了工程进度,提高了效率,节约了成本,满足预定要求。

  3. ALGORITHM OF DETERMINATION OF POWER AND ENERGY INDEXES OF SCREW INTENSIFIER ON THE BULLDOZER WORKING EQUIPMENT AT TRENCH REFILLINGS

    Directory of Open Access Journals (Sweden)

    KROL R. N.

    2016-03-01

    Full Text Available Raising of problem. A bulldozer work at trench refilings is conducted by cyclic, machine shuttle motions that increases a right-of-way; increasing of time charges, fuel and labour by the side of the continuous refilling method. Besides the indicated defects gets worse also the quality of the trench refilling: the uneven soil output into a trench with large portions results the damages of pipes isolation and emptinesses formation, in consequence  settling and washing of soil. A bulldozer with the screw intensifier (SI, is deprived lacks of an odinary bulldozer  moving along a trench, it moves the loose soil that does not fall on a pipeline, but rolles on it. Thus the circuitous speed of a cutting edge of SI exceeds the speed of the base machine moving that provides the strong soil treatment (before dispersion before output into a trench. Purpose. The algorithm development of the rotational moment determination on the SI driveshaft, the consumable energy, the energy intensity and the working process productivity of the reverse trench refillings depending on physical and mechanical properties of soil, geometrical parameters of SI and bulldozer optimal speed. Conclusion. The developed algorithm allows to define that at the fixed value of the rotational speed the rotational moment and indicated efficiency of SI at the optimum speed increasing of the base machine change on a linear law; the optimum speed change of the base machine practically does not influence on the energy intensity at the considered change of the rotational speed .

  4. XRF analysis of turbidites in the Japan Trench: Evidences of provenances?

    Science.gov (United States)

    Schwestermann, Tobias; Fink, Hiske G.; Wefer, Gerold; Fleischmann, Timo; McHugh, Cecilia M.; Ikehara, Ken; Kanamatsu, Toshiya; Kioka, Arata; Strasser, Michael

    2017-04-01

    Since the Mw 9 Tohoku-oki earthquake in 2011, intensive research is going on, in order to analyse earthquake-related changes and fingerprints in the sedimentological record of the Japan Trench. Many turbidites were detected within small depositional trench basins in the central part of the trench by means of high-resolution sub-bottom profiles and sediment cores. There, distinct thick turbidite sequences have been dated by tephra and radiocarbon analyses and correlated to historic earthquakes. However, information on the turbiditeś source areas and, thus, inferences on their causing earthquake characteristics, is so far lacking. For this purpose, this study performs turbidite provenance analyses by detailed petrographic and XRF core scanning analysis on cores retrieved during cruises of R/V Sonne SO-219A and R/V Sonne SO-251A, covering the entire along-strike extent of the Japan Trench from 36° to 40.3°N. Cores were measured on the Avaatech x-ray fluorescence (XRF) core scanner at MARUM, Bremen, with a sampling interval of 1cm with 10kV and 30kV for the elements Al, Si, K, Ca, Ti, Mn, Fe and Rb, Sr, Zr, respectively. First results show distinctly different chemical fingerprints of the various spatially and temporally distributed turbidite sequences. In particular, the fine grained (silt to clay) upper parts of the turbidite sequences have partly distinct trends in elemental ratios, indicating either (i) various source areas, (ii) sorting processes along the turbidités pathways and/or (iii) post-depositional alteration processes. Furthermore, also the coarser basal sequences (mostly composed of multiple fine sand layers and beds) show various trends of elemental ratios. In particular the Fe/Rb vs. density trends can be indicative for the event deposits in the central part of the trench, which have been linked to historic earthquakes. Although, XRF core scanning data from the sand fraction needs to be interpreted with care, also sediment petrographic data (heavy

  5. Conditions Under Which Megathrust Ruptures Propagate Through Shallow Velocity-Weakening Regions to the Trench

    Science.gov (United States)

    Dunham, E. M.; Kozdon, J. E.; Lotto, G. C.

    2012-12-01

    We have conducted dynamic rupture simulations of the 11 March 2011 Tohoku earthquake to identify conditions that permit megathrust ruptures to reach the trench, even when the uppermost portion of the plate interface is frictionally stable. Our models incorporate rate-and-state friction featuring depth-dependent properties that transition from velocity-weakening at depth to velocity-strengthening beneath the accretionary prism. Earthquake nucleation is thus restricted to greater depths, consistent with the lack of shallow seismicity near the trench. Despite this, we find that unless the uppermost velocity-strengthening section of the fault extends beyond about 50 km along dip, ruptures propagating upward from depth break through to the trench. Stress changes, carried by seismic waves released by deep slip, provide the necessary driving force that maintains propagation even in the absence of frictional weakening and stress drop. In our present set of simulations, we assume ideally elastic response of the off-fault material. We therefore caution that our conclusions will likely be modified by the occurrence of plastic deformation within the accretionary prism, which we are planning to explore in the near future. Our models are calibrated through comparison with seafloor deformation measurements and onshore 1-Hz GPS data. We explore the ability of these data sets to constrain frictional properties along the plate interface, particularly in the near-trench region. Our modeling efforts thus far suggest strong trade-offs between stress drop along the deeper part of the fault and the shallow frictional properties. In addition to our preferred model featuring a shallow velocity-strengthening section, we can equally well fit the data with velocity-weakening properties extending all the way to the trench, provided we decrease the average stress drop by reducing the initial effective normal stress. We are also examining the signature of extreme shallow slip in hydroacoustic

  6. Tsunami Modeling of Hikurangi Trench M9 Events: Case Study for Napier, New Zealand

    Science.gov (United States)

    Williams, C. R.; Nyst, M.; Farahani, R.; Bryngelson, J.; Lee, R.; Molas, G.

    2015-12-01

    RMS has developed a tsunami model for New Zealand for the insurance industry to price and to manage their tsunami risks. A key tsunamigenic source for New Zealand is the Hikurangi Trench that lies offshore on the eastside of the North Island. The trench is the result of the subduction of the Pacific Plate beneath the North Island at a rate of 40-45 mm/yr. Though there have been no M9 historical events on the Hikurangi Trench, events in this magnitude range are considered in the latest version of the National Seismic Hazard Maps for New Zealand (Stirling et al., 2012). The RMS modeling approaches the tsunami lifecycle in three stages: event generation, ocean wave propagation, and coastal inundation. The tsunami event generation is modeled based on seafloor deformation resulting from an event rupture model. The ocean wave propagation and coastal inundation are modeled using a RMS-developed numerical solver, implemented on graphic processing units using a finite-volume approach to approximate two-dimensional, shallow-water wave equations over the ocean and complex topography. As the tsunami waves enter shallow water and approach the coast, the RMS model calculates the propagation of the waves along the wet-dry interface considering variable land friction. The initiation and characteristics of the tsunami are based on the event rupture model. As there have been no historical M9 events on the Hikurangi Trench, this rupture characterization posed unique challenges. This study examined the impacts of a suite of event rupture models to understand the key drivers in the variations in the tsunami inundation footprints. The goal was to develop a suite of tsunamigenic event characterizations that represent a range of potential tsunami outcomes for M9 events on the Hikurangi Trench. The focus of this case study is the Napier region as it represents an important exposure concentration in the region and has experience tsunami inundations in the past including during the 1931 Ms7

  7. ENVIRONMENTALLY SOUND DISPOSAL OF RADIOACTIVE MATERIALS AT A RCRA HAZARDOUS WASTE DISPOSAL FACILITY

    Energy Technology Data Exchange (ETDEWEB)

    Romano, Stephen; Welling, Steven; Bell, Simon

    2003-02-27

    The use of hazardous waste disposal facilities permitted under the Resource Conservation and Recovery Act (''RCRA'') to dispose of low concentration and exempt radioactive materials is a cost-effective option for government and industry waste generators. The hazardous and PCB waste disposal facility operated by US Ecology Idaho, Inc. near Grand View, Idaho provides environmentally sound disposal services to both government and private industry waste generators. The Idaho facility is a major recipient of U.S. Army Corps of Engineers FUSRAP program waste and received permit approval to receive an expanded range of radioactive materials in 2001. The site has disposed of more than 300,000 tons of radioactive materials from the federal government during the past five years. This paper presents the capabilities of the Grand View, Idaho hazardous waste facility to accept radioactive materials, site-specific acceptance criteria and performance assessment, radiological safety and environmental monitoring program information.

  8. Nature and Architecture of the Sedimentary Deposits in the Trench of the Ecuadorian Subduction Margin

    Science.gov (United States)

    Gonzalez, Miguel; Proust, Jean-Noel; Michaud, Francois; Pouderoux, Hugo; Ratzov, Gueorgui

    2016-04-01

    The active margin of Ecuador is characterized by strong tectonic erosion that contributes to the formation of a deep trench filled by a complex suite of sedimentary facies. Gravity flow sedimentation is ubiquitous along the margin and facies range from laterally continuous m-thick mass transport deposits to isolated cm-thick turbidites intercalated with hemipelagite and ash layers. However, the nature and architecture of those deposits remain equivocal. This study presents the interpretation of detailed bathymetry, high-resolution seismic profiles and sediment cores recently acquired along the 600 km-long Ecuadorian margin (ATACAMES campaign onboard the R/V L'Atalante, 2012). The margin comprises three morphological segments: (1) the central segment marked by the subduction of the Carnegie Ridge, which induced a narrow (10-30 km wide) and relatively shallow trench (3100-3700 m deep), a steep and gullied continental slope with no canyon and a 20-60 km wide shelf characterized by active subsidence, (2) the northern segment characterized by a wider (~100 km) and deeper (3800-4000 m) trench, a gentler gullied continental slope and similar shelf settings (10-50 km wide), (3) the southern segment presents a wide (20-60 km) and deep (4000-4700 m) trench, a starved continental slope with well-defined canyon systems and a wide subsiding shelf (50-100 km wide). The sedimentary dynamics along the margin is evaluated by the analysis of 15 sediment cores. High-resolution visual description of the cores, X-Ray imagery and the measurement of petrophysical properties (gamma density, magnetic susceptibility, P-wave velocity) led to the identification of 6 sedimentary facies that characterize 6 sedimentary processes: Turbidite beds (turbidity currents), Hemipelagites (continuous marine sedimentation), Tephras (airfall ash layers consecutive to volcanic eruptions), Debris flow deposits (cohesive debris flows), Megaturbidite/Homogenite (large-scale and/or hybrid gravity flows), Mass

  9. Proposal of a SiC disposal canister for very deep borehole disposal

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Heui-Joo; Lee, Minsoo; Lee, Jong-Youl; Kim, Kyungsu [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-10-15

    In this paper authors proposed a silicon carbide, SiC, disposal canister for the DBD concept in Korea. A. Kerber et al. first proposed the SiC canister for a geological disposal of HLW, CANDU or HTR spent nuclear fuels. SiC has some drawbacks in welding or manufacturing a large canister. Thus, we designed a double layered disposal canister consisting of a stainless steel outer layer and a SiC inner layer. KAERI has been interested in developing a very deep borehole disposal (DBD) of HLW generated from pyroprocessing of PWR spent nuclear fuel and supported the relevant R and D with very limited its own budget. KAERI team reviewed the DBD concept proposed by Sandia National Laboratories (SNL) and developed its own concept. The SNL concept was based on the steel disposal canister. The authors developed a new technology called cold spray coating method to manufacture a copper-cast iron disposal canister for a geological disposal of high level waste in Korea. With this method, 8 mm thin copper canister with 400 mm in diameter and 1200 mm in height was made. In general, they do not give any credit on the lifetime of a disposal canister in DBD concept unlike the geological disposal. In such case, the expensive copper canister should be replaced with another one. We designed a disposal canister using SiC for DBD. According to an experience in manufacturing a small size canister, the fabrication of a large-size one is a challenge. Also, welding of SiC canister is not easy. Several pathways are being paved to overcome it.

  10. Geochemical Data Package for the 2005 Hanford Integrated Disposal Facility Performance Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Krupka, Kenneth M.; Serne, R JEFFREY.; Kaplan, D I.

    2004-09-30

    CH2M HILL Hanford Group, Inc. (CH2M HILL) is designing and assessing the performance of an integrated disposal facility (IDF) to receive low-level waste (LLW), mixed low-level waste (MLLW), immobilized low-activity waste (ILAW), and failed or decommissioned melters. The CH2M HILL project to assess the performance of this disposal facility is the Hanford IDF Performance Assessment (PA) activity. The goal of the Hanford IDF PA activity is to provide a reasonable expectation that the disposal of the waste is protective of the general public, groundwater resources, air resources, surface-water resources, and inadvertent intruders. Achieving this goal will require prediction of contaminant migration from the facilities. This migration is expected to occur primarily via the movement of water through the facilities, and the consequent transport of dissolved contaminants in the vadose zone to groundwater where contaminants may be re-introduced to receptors via drinking water wells or mixing in the Columbia River. Pacific Northwest National Laboratory (PNNL) assists CH2M HILL in their performance assessment activities. One of the PNNL tasks is to provide estimates of the geochemical properties of the materials comprising the IDF, the disturbed region around the facility, and the physically undisturbed sediments below the facility (including the vadose zone sediments and the aquifer sediments in the upper unconfined aquifer). The geochemical properties are expressed as parameters that quantify the adsorption of contaminants and the solubility constraints that might apply for those contaminants that may exceed solubility constraints. The common parameters used to quantify adsorption and solubility are the distribution coefficient (Kd) and the thermodynamic solubility product (Ksp), respectively. In this data package, we approximate the solubility of contaminants using a more simplified construct, called the solution concentration limit, a constant value. The Kd values and

  11. Colors in Disposable Diapers: Addressing Myths.

    Science.gov (United States)

    Evans, Eric B; Helmes, C Tucker; Kirsch, Taryn; Ruble, Karen M

    2014-08-01

    Colors are frequently added to disposable diapers to enhance the diapering experience. The colors in the interior of diapers are composed of nonsensitizing pigments that are bound during the fiber-making process into the fibers of the nonwoven that covers the absorbent core materials. In the past, the use of color in diapers has been called into question based on the presumed use of disperse dyes, known sensitizers in the textile industry, and erroneous reports in literature. In fact, disperse dyes are not used in leading disposable diapers; the colors used in these disposable diapers are nonsensitizing pigments with favorable safety profiles. Numerous safety tests, such as skin patch tests with pigments used on diaper backsheets, have found no evidence of skin irritation or sensitization.

  12. AFCI Storage & Disposal FY-06 Progress Report

    Energy Technology Data Exchange (ETDEWEB)

    Halsey, W G; Wigeland, R; Dixon, B

    2006-09-27

    AFCI Storage and Disposal participants at LLNL, ANL and INL provide assessment of how AFCI technology can optimize the future evolution of the fuel cycle, including optimization of waste management. Evaluation of material storage and repository disposal technical issues provides feedback on criteria and metrics for AFCI, and evaluation of AFCI waste streams provides technical alternatives for future repository optimization. LLNL coordinates this effort that includes repository analysis at ANL and incorporation of repository impacts into AFCI criteria at INL. Cooperative evaluation with YMP staff is pursued to provide a mutually agreed technical base. Cooperation with select international programs is supported.

  13. Electrochemical apparatus comprising modified disposable rectangular cuvette

    Science.gov (United States)

    Dattelbaum, Andrew M; Gupta, Gautam; Morris, David E

    2013-09-10

    Electrochemical apparatus includes a disposable rectangular cuvette modified with at least one hole through a side and/or the bottom. Apparatus may include more than one cuvette, which in practice is a disposable rectangular glass or plastic cuvette modified by drilling the hole(s) through. The apparatus include two plates and some means of fastening one plate to the other. The apparatus may be interfaced with a fiber optic or microscope objective, and a spectrometer for spectroscopic studies. The apparatus are suitable for a variety of electrochemical experiments, including surface electrochemistry, bulk electrolysis, and flow cell experiments.

  14. The Vapor Plume at Material Disposal Are C in Relation to Pajarito Corridor Facilities

    Energy Technology Data Exchange (ETDEWEB)

    Masse, William B. [Los Alamos National Laboratory

    2012-04-02

    A vapor plume made up of volatile organic compounds is present beneath Material Disposal Area C (MDA C) at Los Alamos National Laboratory (LANL). The location and concentrations within the vapor plume are discussed in relation to existing and planned facilities and construction activities along Pajarito Road (the 'Pajarito Corridor') and in terms of worker health and safety. This document provides information that indicates that the vapor plume does not pose a threat to the health of LANL workers nor will it pose a threat to workers during construction of proposed facilities along Pajarito Road. The Los Alamos National Laboratory (LANL or the Laboratory) monitors emissions, effluents, and environmental media to meet environmental compliance requirements, determine actions to protect the environment, and monitor the long-term health of the local environment. LANL also studies and characterizes 'legacy' waste from past Laboratory operations to make informed decisions regarding eventual corrective actions and the disposition of that waste. Starting in 1969, these activities have been annually reported in the LANL Environmental Report (formerly Environmental Surveillance Report), and are detailed in publicly accessible technical reports meeting environmental compliance requirements. Included among the legacy sites being investigated are several formerly used material disposal areas (MDAs) set aside by the Laboratory for the general on-site disposal of waste from mission-related activities. One such area is MDA C located in Technical Area 50 (TA-50), which was used for waste disposal between 1948 and 1974. The location of TA-50 is depicted in Figure 1. The present paper uses a series of maps and cross sections to address the public concerns raised about the vapor plume at MDA C. As illustrated here, extensive sampling and data interpretation indicate that the vapor plume at MDA C does not pose a threat to the health of LANL workers nor will it pose a

  15. Annual report RCRA post-closure monitoring and inspections for CAU 112: Area 23 hazardous waste trenches, Nevada Test Site, for the period October 1996--October 1997

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-01-01

    The Area 23 Hazardous Waste Trenches were closed in-place in September 1993. Post-closure monitoring of the Area 23 Hazardous Waste Trenches began in October 1993. The post-closure monitoring program is used to verify that the Area 23 Hazardous Waste Trench covers are performing properly, and that there is no water infiltrating into or out of the waste trenches. The performance of the Area 23 Hazardous Waste Trenches is currently monitored using 30 neutron access tubes positioned on and along the margins of the covers. Soil moisture measurements are obtained in the soils directly beneath the trenches and compared to baseline conditions from the first year of post-closure operation. This report documents the post-closure activities between October 1996 and October 1997.

  16. Annual report, RCRA post-closure monitoring and inspections for the mercury landfill hazardous waste trenches for the period October 1995--October 1996

    Energy Technology Data Exchange (ETDEWEB)

    Emer, D.F.; Smith, J.L.

    1997-01-01

    The Area 23 Hazardous Waste Trenches were closed in-place in September 1993. Post-closure monitoring of the Area 23 Hazardous Waste Trenches began in October 1993. The post-closure monitoring program is used to verify that the Area 23 Hazardous Waste Trench covers are performing properly, and that there is no water infiltrating into the waste trenches. The performance of the Area 23 Hazardous Waste Trenches is currently monitored using 30 neutron access tubes positioned on and along the margins of the covers. Soil moisture measurements are obtained in the soils directly beneath the trenches and compared to baseline conditions from the first year of post-closure operation. This report documents the post-closure activities between October 1995 and October 1996.

  17. Anisotropic relaxation behavior of InGaAs/GaAs selectively grown in narrow trenches on (001) Si substrates

    Science.gov (United States)

    Guo, W.; Mols, Y.; Belz, J.; Beyer, A.; Volz, K.; Schulze, A.; Langer, R.; Kunert, B.

    2017-07-01

    Selective area growth of InGaAs inside highly confined trenches on a pre-patterned (001) Si substrate has the potential of achieving a high III-V crystal quality due to high aspect ratio trapping for improved device functionalities in Si microelectronics. If the trench width is in the range of the hetero-layer thickness, the relaxation mechanism of the mismatched III-V layer is no longer isotropic, which has a strong impact on the device fabrication and performance if not controlled well. The hetero-epitaxial nucleation of InxGa1-xAs on Si can be simplified by using a binary nucleation buffer such as GaAs. A pronounced anisotropy in strain release was observed for the growth of InxGa1-xAs on a fully relaxed GaAs buffer with a (001) surface inside 20 and 100 nm wide trenches, exploring the full composition range from GaAs to InAs. Perpendicular to the trench orientation (direction of high confinement), the strain release in InxGa1-xAs is very efficiently caused by elastic relaxation without defect formation, although a small compressive force is still induced by the trench side walls. In contrast, the strain release along the trenches is governed by plastic relaxation once the vertical film thickness has clearly exceeded the critical layer thickness. On the other hand, the monolithic deposition of mismatched InxGa1-xAs directly into a V-shaped trench bottom with {111} Si planes leads instantly to a pronounced nucleation of misfit dislocations along the {111} Si/III-V interfaces. In this case, elastic relaxation no longer plays a role as the strain release is ensured by plastic relaxation in both directions. Hence, using a ternary seed layer facilitates the integration of InxGa1-xAs covering the full composition range.

  18. Transuranic advanced disposal systems: preliminary /sup 239/Pu waste-disposal criteria for Hanford

    Energy Technology Data Exchange (ETDEWEB)

    Kennedy, W.E. Jr.; Aaberg, R.L.; Napier, B.A.; Soldat, J.K.

    1982-09-01

    This report contains the draft results of a study sponsored by the US Department of Energy (DOE) to determine preliminary /sup 239/Pu waste disposal criteria for the Hanford Site. The purpose of this study is to provide a preliminary evaluation of the feasibility of various defense TRU advanced disposal options at the Hanford Site. Advanced waste disposal options include those developed to provide greater confinement than provided by shallow-land burial. They will be used to complement the waste geologic disposal in achieving permanent disposal of selected TRU wastes. An example systems analysis is discussed with assumed performance objectives and Hanford-specific disposal conditions, waste forms, site characteristics, and engineered barriers. Preliminary waste disposal criteria for /sup 239/Pu are determined by applying the Allowable Residual Contamination Level (ARCL) method. This method is based on compliance with a radiation dose rate limit through a site-specific analysis of the potential for radiation exposure to individuals. A 10,000-year environmental performance period is assumed, and the dose rate limit for human intrusion is assumed to be 500 mrem/yr to any exposed individual. Preliminary waste disposal criteria derived by this method for /sup 239/Pu in soils at the Hanford Site are: 0.5 nCi/g in soils between the surface and a depth of 1 m, 2200 nCi/g of soil at a depth of 5 m, and 10,000 nCi/g of soil at depths 10 m and below. These waste disposal criteria are based on exposure scenarios that reflect the dependence of exposure versus burial depth. 5 figures, 7 tables.

  19. Estimation of the Variation of Matric Suction with Respect to Depth in a Vertical Unsaturated Soil Trench Associated with Rainfall Infiltration

    OpenAIRE

    Oh Won Taek; Vanapalli Sai K.; Qi Shunchao; Han Zhong

    2016-01-01

    Soil trenching is extensively used in geotechnical, mining, tunneling and geo-environmental infrastructures. Safe height and stand-up time are two key factors that are required for the rational design of soil trenches. Rainfall infiltration has a significant influence on the safe height and stand-up time of unsaturated soil trenches since it can significantly alter the shear strength of soils by influencing the matric suction. In other words, predicting the variation of matric suction of soil...

  20. Urban garbage disposal and management in China

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    This paper, probing into the present situation of urban domestic garbage by analyzing its growing trend, compositional change andregional difference, reveals the problems existing in its disposal and management in China. Meanwhile, a questionnaire was conducted in fivebig cities around China for surveying urban residents' attitudes towards garbage disposal and management policies and measures. Results showedthe output of urban domestic garbage in Chinese cities is ever increasing, and the recoverable materials and energy in garbage composition arealso increasing. The population growth, economic development, and increase of residents' expenditure level are the main factors influencing thegrowing output and changing composition of the garbage. Information acquired from the questionnaire showed that majority of the urban residentsare in favor of the garbage reduction policies and managerial measures and are willing to collaborate with municipal government in battlingagainst garbage.Based on the analysis and questionnaire, some polieymaking-oriented suggestions such as operating the garbage disposal from a socialwelfare service to a sector of profit-gaining enterprises, transferring the garbage management from passive end control to active source control,promoting the classified garbage collection in cities around China, and charging garbage fees for its cleanup and disposal, have also been putforward in the paper.

  1. Recycling disposable cups into paper plastic composites.

    Science.gov (United States)

    Mitchell, Jonathan; Vandeperre, Luc; Dvorak, Rob; Kosior, Ed; Tarverdi, Karnik; Cheeseman, Christopher

    2014-11-01

    The majority of disposable cups are made from paper plastic laminates (PPL) which consist of high quality cellulose fibre with a thin internal polyethylene coating. There are limited recycling options for PPLs and this has contributed to disposable cups becoming a high profile, problematic waste. In this work disposable cups have been shredded to form PPL flakes and these have been used to reinforce polypropylene to form novel paper plastic composites (PPCs). The PPL flakes and polypropylene were mixed, extruded, pelletised and injection moulded at low temperatures to prevent degradation of the cellulose fibres. The level of PPL flake addition and the use of a maleated polyolefin coupling agent to enhance interfacial adhesion have been investigated. Samples have been characterised using tensile testing, dynamic mechanical analysis (DMA) and thermogravimetric analysis. Use of a coupling agent allows composites containing 40 wt.% of PPL flakes to increase tensile strength of PP by 50% to 30 MPa. The Young modulus also increases from 1 to 2.5 GPa and the work to fracture increases by a factor of 5. The work demonstrates that PPL disposable cups have potential to be beneficially reused as reinforcement in novel polypropylene composites.

  2. Military Throwaways Why Acquirers Should Go Disposable

    Science.gov (United States)

    2016-02-01

    would fit within the current budget limitations, grounded in a reasonableness determined by fair market value . As with anything, the determination...of “reasonableness” depends greatly on the environment and facts surrounding the pro - curement. Based upon the timelines a disposable tech policy

  3. Laboratory Waste Disposal Manual. Revised Edition.

    Science.gov (United States)

    Stephenson, F. G., Ed.

    This manual is designed to provide laboratory personnel with information about chemical hazards and ways of disposing of chemical wastes with minimum contamination of the environment. The manual contains a reference chart section which has alphabetical listings of some 1200 chemical substances with information on the health, fire and reactivity…

  4. Using fuzzy logic analysis for siting decisions of infiltration trenches for highway runoff control.

    Science.gov (United States)

    Ki, Seo Jin; Ray, Chittaranjan

    2014-09-15

    Determining optimal locations for best management practices (BMPs), including their field considerations and limitations, plays an important role for effective stormwater management. However, these issues have been often overlooked in modeling studies that focused on downstream water quality benefits. This study illustrates the methodology of locating infiltration trenches at suitable locations from spatial overlay analyses which combine multiple layers that address different aspects of field application into a composite map. Using seven thematic layers for each analysis, fuzzy logic was employed to develop a site suitability map for infiltration trenches, whereas the DRASTIC method was used to produce a groundwater vulnerability map on the island of Oahu, Hawaii, USA. In addition, the analytic hierarchy process (AHP), one of the most popular overlay analyses, was used for comparison to fuzzy logic. The results showed that the AHP and fuzzy logic methods developed significantly different index maps in terms of best locations and suitability scores. Specifically, the AHP method provided a maximum level of site suitability due to its inherent aggregation approach of all input layers in a linear equation. The most eligible areas in locating infiltration trenches were determined from the superposition of the site suitability and groundwater vulnerability maps using the fuzzy AND operator. The resulting map successfully balanced qualification criteria for a low risk of groundwater contamination and the best BMP site selection. The results of the sensitivity analysis showed that the suitability scores were strongly affected by the algorithms embedded in fuzzy logic; therefore, caution is recommended with their use in overlay analysis. Accordingly, this study demonstrates that the fuzzy logic analysis can not only be used to improve spatial decision quality along with other overlay approaches, but also is combined with general water quality models for initial and refined

  5. Highly nonlinear sub-micron silicon nitride trench waveguide coated with gold nanoparticles

    Science.gov (United States)

    Huang, Yuewang; Zhao, Qiancheng; Sharac, Nicholas; Ragan, Regina; Boyraz, Ozdal

    2015-05-01

    We demonstrate the fabrication of a highly nonlinear sub-micron silicon nitride trench waveguide coated with gold nanoparticles for plasmonic enhancement. The average enhancement effect is evaluated by measuring the spectral broadening effect caused by self-phase-modulation. The nonlinear refractive index n2 was measured to be 7.0917×10-19 m2/W for a waveguide whose Wopen is 5 μm. Several waveguides at different locations on one wafer were measured in order to take the randomness of the nanoparticle distribution into consideration. The largest enhancement is measured to be as high as 10 times. Fabrication of this waveguide started with a MEMS grade photomask. By using conventional optical lithography, the wide linewidth was transferred to a wafer. Then the wafer was etched anisotropically by potassium hydroxide (KOH) to engrave trapezoidal trenches with an angle of 54.7º. Side wall roughness was mitigated by KOH etching and thermal oxidation that was used to generate a buffer layer for silicon nitride waveguide. The guiding material silicon nitride was then deposited by low pressure chemical vapor deposition. The waveguide was then patterned with a chemical template, with 20 nm gold particles being chemically attached to the functionalized poly(methyl methacrylate) domains. Since the particles attached only to the PMMA domains, they were confined to localized regions, therefore forcing the nanoparticles into clusters of various numbers and geometries. Experiments reveal that the waveguide has negligible nonlinear absorption loss, and its nonlinear refractive index can be greatly enhanced by gold nano clusters. The silicon nitride trench waveguide has large nonlinear refractive index, rendering itself promising for nonlinear applications.

  6. A global outer-rise/outer-trench-slope (OR/OTS) earthquake study

    Science.gov (United States)

    Wartman, J. M.; Kita, S.; Kirby, S. H.; Choy, G. L.

    2009-12-01

    Using improved seismic, bathymetric, satellite gravity and other geophysical data, we investigated the seismicity patterns and focal mechanisms of earthquakes in oceanic lithosphere off the trenches of the world that are large enough to be well recorded at teleseismic distances. A number of prominent trends are apparent, some of which have been previously recognized based on more limited data [1], and some of which are largely new [2-5]: (1) The largest events and the highest seismicity rates tend to occur where Mesozoic incoming plates are subducting at high rates (e.g., those in the western Pacific and the Banda segment of Indonesia). The largest events are predominantly shallow normal faulting (SNF) earthquakes. Less common are reverse-faulting (RF) events that tend to be deeper and to be present along with SNF events where nearby seamounts, seamount chains and other volcanic features are subducting [Seno and Yamanaka, 1996]. Blooms of SNF OR/OTS events usually occur just after and seaward of great interplate thrust (IPT) earthquakes but are far less common after smaller IPT events. (2) Plates subducting at slow rates (Shetlands). (4) Subducting plates of intermediate age (20 to about 65 Ma) display a diversity of focal mechanisms and seismicity patterns. In the Philippines, NE Indonesia, and Melanesia, bands of reverse faulting events occur at or near the trench and SNF earthquakes are restricted to OR/OTS sites further from the trench. (5) Clustering of OR/OTS events of all types commonly occurs where seamount chains, volcanic ridges, or volcanic plateaus enter OR/OTS regions (e.g., the Louisville Ridge in Tonga, the Juan Fernandez Ridge in Chile, the Ninety East Ridge in Sumatra, and the D’Entrecastaux Ridge in Vanuatu).

  7. Shooting from the Trenches: On the Impossibility and Inability to think about the War

    Directory of Open Access Journals (Sweden)

    Chris van der Heijden

    2013-06-01

    Full Text Available In this essay Chris van der Heijden (Dat nooit meer [Never Again] answers his critics. He accepts in general what Bob Moore says, although his criticism is rather abstract. He does agree partly with Koes Aerts, but not on some crucial points – for example the method. Van der Heijden doesn’t agree at all with Wielenga, not so much because of arguments but exactly because of the lack of it. In the debate with Wielenga, he contends, the trench warfare, which is going on since almost ten years, simply goes on. According to Van der Heijden it leads to nothing.

  8. Filling high aspect ratio trenches by superconformal chemical vapor deposition: Predictive modeling and experiment

    Science.gov (United States)

    Wang, Wenjiao B.; Abelson, John R.

    2014-11-01

    Complete filling of a deep recessed structure with a second material is a challenge in many areas of nanotechnology fabrication. A newly discovered superconformal coating method, applicable in chemical vapor deposition systems that utilize a precursor in combination with a co-reactant, can solve this problem. However, filling is a dynamic process in which the trench progressively narrows and the aspect ratio (AR) increases. This reduces species diffusion within the trench and may drive the component partial pressures out of the regime for superconformal coating. We therefore derive two theoretical models that can predict the possibility for filling. First, we recast the diffusion-reaction equation for the case of a sidewall with variable taper angle. This affords a definition of effective AR, which is larger than the nominal AR due to the reduced species transport. We then derive the coating profile, both for superconformal and for conformal coating. The critical (most difficult) step in the filling process occurs when the sidewalls merge at the bottom of the trench to form the V shape. Experimentally, for the Mg(DMADB)2/H2O system and a starting AR = 9, this model predicts that complete filling will not be possible, whereas experimentally we do obtain complete filling. We then hypothesize that glancing-angle, long-range transport of species may be responsible for the better than predicted filling. To account for the variable range of species transport, we construct a ballistic transport model. This incorporates the incident flux from outside the structure, cosine law re-emission from surfaces, and line-of-sight transport between internal surfaces. We cast the transport probability between all positions within the trench into a matrix that represents the redistribution of flux after one cycle of collisions. Matrix manipulation then affords a computationally efficient means to determine the steady-state flux distribution and growth rate for a given taper angle. The

  9. Deformation structures in the frontal prism near the Japan Trench: Insights from sandbox models

    Science.gov (United States)

    Saha, Puspendu; Bose, Santanu

    2016-04-01

    Subduction of bathymetric features in the oceanic plate, e.g., seamounts, aseismic ridges, volcanic plateaus has a strong influence on the development of morphological features and deformation structures in the overriding plate. For example, the subduction of seamounts correlates to a steeper surface slope in the inner wedge than that in the outer wedge. Conversely, the subduction of aseismic ridges causes the development of a steep outer wedge slope and with almost flat inner wedge. Despite the dominance of horst-and-graben structure at many trenches, its influence on frontal wedge growth remains relatively unexplored. We have used sandbox experiments to explore the mechanics of the frontal prism structures near the Japan Trench documented by seismic reflection data and new borehole from IODP Expedition 343 (JFAST). This study investigated the effects of down-dip (normal to trench axis) variations in frictional resistance along a decollement on the structural development of the frontal wedges near subduction zones. Interpretation of seismic reflection images indicates that the wedge has been affected by trench-parallel horst-and-graben structures in the subducting plate. We performed sandbox experiments with down-dip patches of relatively high and low friction on the basal decollement to simulate the effect of variable coupling over subducting oceanic plate topography. Our experiments suggest that high frictional resistance on the basal fault can produce the internal deformation and fault-and-fold structures observed in the frontal wedge by the JFAST expedition. Subduction of patches of varying friction cause a temporal change in the style of internal deformation within the wedge and gave rise to two distinctive structural domains, separated by a break in the surface slope of the wedge: (i) complexly deformed inner wedge with steep surface slope, and (ii) shallow taper outer wedge with a sequence of imbricate thrusts. Our experiments further demonstrate that the

  10. COMPILATION OF DISPOSABLE SOLID WASTE CASK EVALUATIONS

    Energy Technology Data Exchange (ETDEWEB)

    THIELGES, J.R.; CHASTAIN, S.A.

    2007-06-21

    The Disposable Solid Waste Cask (DSWC) is a shielded cask capable of transporting, storing, and disposing of six non-fuel core components or approximately 27 cubic feet of radioactive solid waste. Five existing DSWCs are candidates for use in storing and disposing of non-fuel core components and radioactive solid waste from the Interim Examination and Maintenance Cell, ultimately shipping them to the 200 West Area disposal site for burial. A series of inspections, studies, analyses, and modifications were performed to ensure that these casks can be used to safely ship solid waste. These inspections, studies, analyses, and modifications are summarized and attached in this report. Visual inspection of the casks interiors provided information with respect to condition of the casks inner liners. Because water was allowed to enter the casks for varying lengths of time, condition of the cask liner pipe to bottom plate weld was of concern. Based on the visual inspection and a corrosion study, it was concluded that four of the five casks can be used from a corrosion standpoint. Only DSWC S/N-004 would need additional inspection and analysis to determine its usefulness. The five remaining DSWCs underwent some modification to prepare them for use. The existing cask lifting inserts were found to be corroded and deemed unusable. New lifting anchor bolts were installed to replace the existing anchors. Alternate lift lugs were fabricated for use with the new lifting anchor bolts. The cask tiedown frame was modified to facilitate adjustment of the cask tiedowns. As a result of the above mentioned inspections, studies, analysis, and modifications, four of the five existing casks can be used to store and transport waste from the Interim Examination and Maintenance Cell to the disposal site for burial. The fifth cask, DSWC S/N-004, would require further inspections before it could be used.

  11. Trench mouth

    Science.gov (United States)

    ... 2016 Updated by: Michael Kapner, DDS, general and aesthetic dentistry, Norwalk Medical Center, Norwalk, CT. Review provided ... for EHRs For Developers U.S. National Library of Medicine 8600 Rockville Pike, Bethesda, MD 20894 U.S. Department ...

  12. Automated system for monitoring groundwater levels at an experimental low-level waste disposal site

    Energy Technology Data Exchange (ETDEWEB)

    Newbold, J.D.; Bogle, M.A.

    1984-06-01

    One of the major problems with disposing of low-level solid wastes in the eastern United States is the potential for water-waste interactions and leachate migration. To monitor groundwater fluctuations and the frequency with which groundwater comes into contact with a group of experimental trenches, work at Oak Ridge National Laboratory's Engineered Test Facility (ETF) has employed a network of water level recorders that feed information from 15 on-site wells to a centralized data recording system. The purpose of this report is to describe the monitoring system being used and to document the computer programs that have been developed to process the data. Included in this report are data based on more than 2 years of water level information for ETF wells 1 through 12 and more than 6 months of data from all 15 wells. The data thus reflect both long-term trends as well as a large number of short-term responses to individual storm events. The system was designed to meet the specific needs of the ETF, but the hardware and computer routines have generic application to a variety of groundwater monitoring situations. 5 references.

  13. Technical issues associated with in situ vitrification of the INEL Subsurface Disposal Area

    Energy Technology Data Exchange (ETDEWEB)

    Stoots, C.M.; Bates, S.O.; Callow, R.A.; Campbell, K.A.; Farnsworth, R.K.; Krisman, G.K.; McKellar, M.G.; Nickelson, D.F.; Slater, C.E.

    1992-07-01

    In situ vitrification (ISV) has been identified as an alternative technology for remediation of the acid pit and transuranic pits and trenches (TRU-PTs) at the Idaho National Engineering Laboratory (INEL) Subsurface Disposal Area (SDA). However, a number of technical issues must be resolved before ISV can be considered applicable to these waste sites. To assist in the ISV technology evaluation, an ISV Steering Committee was formed to identify, prioritize, and develop closure roadmaps for technical issues lated with ISV application at the SDA. The activities of the ISV Steering Committee are summarized in a three-volume report. Volume I identifies the systematic approach used to identify and prioritize the ISV technical issues and briefly discusses the methodology that will be employed to resolve these issues. Volumes 2 and 3 discuss each technical issue in greater detail and suggest specific closure roadmaps to be used in resolving technical issues associated with ISV at the SDA Acid Pit and TRU-PTS, respectively. The three-volume report is a working document that will be updated as necessary to reflect current evaluation strategy for the ISV technology. This is Volume 3.

  14. Technical issues associated with in situ vitrification of the INEL Subsurface Disposal Area

    Energy Technology Data Exchange (ETDEWEB)

    Stoots, C.M.; Bates, S.O.; Callow, R.A.; Campbell, K.A.; Farnsworth, R.K.; Gratson, G.K.; McKellar, M.G.; Nickelson, D.F.; Slater, C.E.

    1992-01-01

    In situ vitrification (ISV) has been identified as an alternative technology for remediation of the Acid Pit and Transuranic Pits and Trenches (TRU-PTs) that are present at the Idaho National Engineering Laboratory (INEL) Subsurface Disposal Area (SDA). However, a number of technical issues exist that must be resolved before ISV can be considered applicable to these waste sites. To assist in the ISV technology evaluation, an ISV Steering Committee was formed to identify, prioritize, and develop closure roadmaps for technical issues associated with ISV application at the INEL SDA. The activities of the ISV Steering Committee are summarized in three volumes of this report. Volume 1 identifies the systematic approach used to identify and prioritize the ISV technical issues, and briefly discusses the methodology that will be employed to resolve these issues. This document Volume 2 and Volume 3 discusses each technical issue in greater detail and suggest specific closure roadmaps to be used in resolving technical issues associated with ISV at the SDA Acid Pit and TRU-PTs, respectively.

  15. Problems and prospects of refuse disposal in nigerian urban centres ...

    African Journals Online (AJOL)

    Refuse disposal is one of the major environmental problems that developing countries are faced with. Health hazard, traffic ... The problem of waste management has two parts, that of collection and that of disposal. Communal collection, block ...

  16. 40 CFR 229.3 - Transportation and disposal of vessels.

    Science.gov (United States)

    2010-07-01

    ... of these vessels shall take place in a site designated on current nautical charts for the disposal of... week, of the exact coordinates of the disposal site so that it may be marked on appropriate charts....

  17. Dredge spoil disposal off Kavaratti Island, Lakshadweep, India

    Digital Repository Service at National Institute of Oceanography (India)

    Chandramohan, P.; SanilKumar, V.; Jayakumar, S.

    Maintenance dredging has been carried out along the navigational channel at Kavaratii Island and dredge spoil is disposed in the open sea. This paper describes the movement of sediment plume while dredging and disposal. The study indicates...

  18. Advanced disposal systems for transuranic waste: Preliminary disposal criteria for Plutonium-239 at Hanford

    Energy Technology Data Exchange (ETDEWEB)

    Kennedy, W.E.; Napier, B.A.; Soldat, J.K.

    1983-01-01

    An evaluation of the feasibility and potential application of advanced disposal systems is being conducted for defense transuranic (TRU) wastes at the Hanford site. The advanced waste disposal options include those developed to provide ''greater confinement'' than provided by shallow-land burial. An example systems analysis is discussed with assumed performance objectives and various Hanford-specific disposal conditions, waste forms, site characteristics, and engineered barriers. Preliminary waste disposal criteria for /sup 239/Pu are determined by applying the allowable residual contamination level (ARCL) method. This method is based on compliance with a radiation dose rate limit through a site specific analysis of the potential for radiation exposure to individuals. A 10,000-year environmental performance period is assumed, and the dose rate limit for human intrusion is assumed to be 500 mrem/yr to any exposed individual. Preliminary waste disposal criteria derived by this method for /sup 239/Pu in soils at the Hanford Site are 0.5 nCi/g in soils between the surface and a depth of 1 m, 2200 nCi/g of soil at a depth of 5 m, and 10,000 nCi/g of soil at depths 10 m and below. These waste disposal criteria are based on exposure scenarios that reflect the dependence of exposure versus burial depth.

  19. Transuranic advanced disposal systems: preliminary /sup 239/Pu waste-disposal criteria for Hanford

    Energy Technology Data Exchange (ETDEWEB)

    Kennedy, W.E. Jr.; Napier, B.A.; Soldat, J.K.

    1982-08-01

    An evaluation of the feasibility and potential application of advanced disposal systems is being conducted for defense transuranic (TRU) wastes at the Hanford Site. The advanced waste disposal options include those developed to provide greater confinement than provided by shallow-land burial. An example systems analysis is discussed with assumed performance objectives and various Hanford-specific disposal conditions, waste forms, site characteristics, and engineered barriers. Preliminary waste disposal criteria for /sup 239/Pu are determined by applying the Allowable Residual Contamination Level (ARCL) method. This method is based on compliance with a radiation dose rate limit through a site-specific analysis of the potential for radiation exposure to individuals. A 10,000 year environmental performance period is assumed, and the dose rate limit for human intrusion is assumed to be 500 mrem/y to any exposed individual. Preliminary waste disposal criteria derived by this method for /sup 239/Pu in soils at the Hanford Site are: 0.5 nCi/g in soils between the surface and a depth of 1 m, 2200 nCi/g of soil at a depth of 5 m, and 10,000 nCi/g of soil at depths 10 m and below. These waste disposal criteria are based on exposure scenarios that reflect the dependence of exposure versus burial depth. 2 figures, 5 tables.

  20. ALTERNATIVES ANALYSIS FOR SELECTING ET #3 SITE

    Energy Technology Data Exchange (ETDEWEB)

    Collard, L.; Hamm, L.

    2012-02-13

    Engineered trenches (ETs) are considered to be a cost-effective method for disposing Low Level Waste (LLW). Based on waste forecasts from waste generators, the last engineered trench in operation (ET No.2) is anticipated to close in FY14, requiring development of a new ET. Solid Waste requested that SRNL develop an assessment report that reviews four disposal options for this new ET (ET No.3) and determine which option would provide the 'best' Performance Assessment (PA) disposal limits for LLW (Appendix A). Those four options (see option footprint locations in Figure 1-1) are: (1) Disposal at grade on TRU Pads 7-13 where soil would be mounded over waste packages; (2) Excavation at a slightly modified SLIT No.13 location - near the Used Equipment Storage Area; (3) Excavation at a modified SLIT No.12 location - near the 643-26E Naval Reactor Component Disposal Area; and (4) Excavation east of TRU Pad No.26 that replaces northeast portions of four slit trench (ST) disposal units in the eastern set of STs. The assessment consisted of both quantitative and qualitative analyses. The quantitative analysis captured key aspects that were readily quantifiable and had predictable impacts on limits and doses. A simplified modeling strategy stemming from current Special Analysis (SA) practices was employed. Both inventory capacity for a specific nuclide (a quasi-inventory limit) and overall performance for specified inventory mixtures (doses resulting from historical inventories) were considered. The qualitative analysis evaluated other key aspects based on engineering judgment in the form of pros and cons.