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Overview of Low-Level Waste Disposal Operations at the Nevada Test Site
The U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office Environmental Management Program is charged with the responsibility to carry out the disposal of on-site and off-site generated low-level radioactive waste at the Nevada Test Site. Core elements of this mission are ensuring that disposal take place in a manner that is safe and cost-effective while protecting workers, the public, and the environment. This paper focuses on giving an overview of the Nevada Test Site facilities regarding currant design of disposal. In addition, technical attributes of the facilities established through the site characterization process will be further described. An update on current waste disposal volumes and capabilities will also be provided. This discussion leads to anticipated volume projections and disposal site requirements as the Nevada Test Site disposal operations look towards the future.
Date:
February 1, 2007
Creator:
/Navarro, DOE
Object Type:
Article
System:
The UNT Digital Library
The Changing Adventures of Mixed Low-Level Waste Disposal at the Nevada Test Site
After a 15-year hiatus, the United States Department of Energy (DOE) National Nuclear Security Administration Nevada Site Office (NNSA/NSO) began accepting DOE off-site generated mixed low-level radioactive waste (MLLW) for disposal at the Nevada Test Site (NTS) in December 2005. This action was predicated on the acceptance by the Nevada Division of Environmental Protection (NDEP) of a waste analysis plan (WAP). The NNSA/NSO agreed to limit mixed waste disposal to 20,000 cubic meters (approximately 706,000 cubic feet) and close the facility by December 2010 or sooner, if the volume limit is reached. The WAP and implementing procedures were developed based on Hanford’s system of verification to the extent possible so the two regional disposal sites could have similar processes. Since the NNSA/NSO does not have a breaching facility to allow the opening of boxes at the site, verification of the waste occurs by visual inspection at the generator/treatment facility or by Real-Time-Radiography (RTR) at the NTS. This system allows the NTS to effectively, efficiently, and compliantly accept MLLW for disposal. The WAP, NTS Waste Acceptance Criteria, and procedures have been revised based on learning experiences. These changes include: RTR expectations; visual inspection techniques; tamper-indicating device selection; void space requirements; and …
Date:
February 1, 2007
Creator:
/Navarro/NSTec, DOE
Object Type:
Article
System:
The UNT Digital Library
Advanced, Low/Zero Emission Boiler Design and Operation
In partnership with the U.S. Department of Energy's National Energy Technology Laboratory, B&W and Air Liquide are developing and optimizing the oxy-combustion process for retrofitting existing boilers as well as new plants. The main objectives of the project is to: (1) demonstrate the feasibility of the oxy-combustion technology with flue gas recycle in a 5-million Btu/hr coal-fired pilot boiler, (2) measure its performances in terms of emissions and boiler efficiency while selecting the right oxygen injection and flue gas recycle strategies, and (3) perform technical and economic feasibility studies for application of the technology in demonstration and commercial scale boilers. This document summarizes the work performed during the period of performance of the project (Oct 2002 to June 2007). Detailed technical results are reported in corresponding topical reports that are attached as an appendix to this report. Task 1 (Site Preparation) has been completed in 2003. The experimental pilot-scale O{sub 2}/CO{sub 2} combustion tests of Task 2 (experimental test performance) has been completed in Q2 2004. Process simulation and cost assessment of Task 3 (Techno-Economic Study) has been completed in Q1 2005. The topical report on Task 3 has been finalized and submitted to DOE in Q3 2005. The calculations …
Date:
June 30, 2007
Creator:
/Wilcox, Babcock; Geological, Illinois State; Parsons, Worley & Group, Parsons Infrastructure /Technology
Object Type:
Report
System:
The UNT Digital Library
Scaled Experimental Modeling of VHTR Plenum Flows
Abstract The Very High Temperature Reactor (VHTR) is the leading candidate for the Next Generation Nuclear Power (NGNP) Project in the U.S. which has the goal of demonstrating the production of emissions free electricity and hydrogen by 2015. Various scaled heated gas and water flow facilities were investigated for modeling VHTR upper and lower plenum flows during the decay heat portion of a pressurized conduction-cooldown scenario and for modeling thermal mixing and stratification (“thermal striping”) in the lower plenum during normal operation. It was concluded, based on phenomena scaling and instrumentation and other practical considerations, that a heated water flow scale model facility is preferable to a heated gas flow facility and to unheated facilities which use fluids with ranges of density to simulate the density effect of heating. For a heated water flow lower plenum model, both the Richardson numbers and Reynolds numbers may be approximately matched for conduction-cooldown natural circulation conditions. Thermal mixing during normal operation may be simulated but at lower, but still fully turbulent, Reynolds numbers than in the prototype. Natural circulation flows in the upper plenum may also be simulated in a separate heated water flow facility that uses the same plumbing as the lower …
Date:
April 1, 2007
Creator:
15, ICONE
Object Type:
Article
System:
The UNT Digital Library
Focal Plane Metrology for the LSST Camera
Meeting the science goals for the Large Synoptic Survey Telescope (LSST) translates into a demanding set of imaging performance requirements for the optical system over a wide (3.5{sup o}) field of view. In turn, meeting those imaging requirements necessitates maintaining precise control of the focal plane surface (10 {micro}m P-V) over the entire field of view (640 mm diameter) at the operating temperature (T {approx} -100 C) and over the operational elevation angle range. We briefly describe the hierarchical design approach for the LSST Camera focal plane and the baseline design for assembling the flat focal plane at room temperature. Preliminary results of gravity load and thermal distortion calculations are provided, and early metrological verification of candidate materials under cold thermal conditions are presented. A detailed, generalized method for stitching together sparse metrology data originating from differential, non-contact metrological data acquisition spanning multiple (non-continuous) sensor surfaces making up the focal plane, is described and demonstrated. Finally, we describe some in situ alignment verification alternatives, some of which may be integrated into the camera's focal plane.
Date:
January 10, 2007
Creator:
A Rasmussen, Andrew P.; Hale, Layton; Kim, Peter; Lee, Eric; Perl, Martin; Schindler, Rafe et al.
Object Type:
Article
System:
The UNT Digital Library
Effects of Global Boundary and Local Collisionality on Magnetic Reconnection in a Laboratory Plasma
The magnetic reconnection process is studied in a wide range of operating conditions in the well-controlled Magnetic Reconnection Experiment. The reconnection rate is observed to be a function of both global (i.e., system size) and local (collisionality) plasma parameters. When only local collisionality is lowered, the current sheet is shortened while effective resistivity is enhanced, both accelerating reconnection rates. At a fixed collisionality, the current sheet length increases with system size, resulting in the reduction of the reconnection rate. These results quantitatively agree with a generalized Sweet-Parker analysis.
Date:
July 24, 2007
Creator:
A. Kuritsyn, H. Ji, S.P. Gerhardt, Y. Ren, and M. Yamada
Object Type:
Report
System:
The UNT Digital Library
Pressure-induced Breaking of Equilibrium Flux Surfaces in the W7AS Stellarator
Calculations are presented for two shots in the W7AS stellarator which differ only in the magnitude of the current in the divertor control coil, but have very different values of experimentally attainable β (<β> ≈ 2.7% versus <β> ≈ 1.8%). Equilibrium calculations find that a region of chaotic magnetic field line trajectories fills approximately the outer 1/3 of the cross-section in each of these configurations. The field lines in the stochastic region are calculated to behave as if the flux surfaces are broken only locally near the outer midplane and are preserved elsewhere. The calculated magnetic field line diffusion coefficients in the stochastic regions for the two shots are consistent with the observed differences in the attainable β, and are also consistent with the differences in the reconstructed pressure profiles.
Date:
April 24, 2007
Creator:
A. Reiman, M.C. Zarnstorff, D. Monticello, A. Weller, J. Geiger, and the W7-AS Team
Object Type:
Article
System:
The UNT Digital Library
Gordon Conference - Cluster, Nanocrystals and Nanostructures - July 29th - August 3rd, 2007
None
Date:
June 14, 2007
Creator:
A. Welford Castleman, Jr.
Object Type:
Report
System:
The UNT Digital Library
Optical simulations of the ion beam emittance growth in different types of a gridded lens
N/A
Date:
April 1, 2007
Creator:
A., Pikin
Object Type:
Report
System:
The UNT Digital Library
EXAMPLE OF A RISK BASED DISPOSAL APPROVAL SOLIDIFICATION OF HANFORD SITE TRANSURANIC (TRU) WASTE
The Hanford Site requested, and the U.S. Environmental Protection Agency (EPA) Region 10 approved, a Toxic Substances Control Act of 1976 (TSCA) risk-based disposal approval (RBDA) for solidifying approximately four cubic meters of waste from a specific area of one of the K East Basin: the North Loadout Pit (NLOP). The NLOP waste is a highly radioactive sludge that contained polychlorinated biphenyls (PCBs) regulated under TSCA. The prescribed disposal method for liquid PCB waste under TSCA regulations is either thermal treatment or decontamination. Due to the radioactive nature of the waste, however, neither thermal treatment nor decontamination was a viable option. As a result, the proposed treatment consisted of solidifying the material to comply with waste acceptance criteria at the Waste Isolation Pilot Plant (WPP) in Carlsbad, New Mexico, or possibly the Environmental Restoration Disposal Facility at the Hanford Site, depending on the resulting transuranic (TRU) content of the stabilized waste. The RBDA evaluated environmental risks associated with potential airborne PCBs. In addition, the RBDA made use of waste management controls already in place at the treatment unit. The treatment unit, the T Plant Complex, is a Resource Conservation and Recovery Act of 1976 (RCRA)-permitted facility used for storing and …
Date:
November 14, 2007
Creator:
AL, PRIGNANO
Object Type:
Article
System:
The UNT Digital Library
Development of An On-Line, Core Power Distribution Monitoring System
The objective of the proposed work was to develop a software package that can construct in three-dimensional core power distributions using the signals from constant temperature power sensors distributed in the reactor core. The software developed uses a mode-based state/parameter estmation technique that is particularly attractive when there are model uncertainties and/or large signal noise. The software yields the expected value of local power at the detector locations and points in between, as well as the probability distribution of the local power density
Date:
October 2, 2007
Creator:
ALdemir, Tunc; Miller, Don & Wang, Peng
Object Type:
Report
System:
The UNT Digital Library
An Archaeological Survey of Proposed Water Pipeline Route Improvements and Deep Well Location for the Cross Country Water Supply Corporation
Archaeological survey results of proposed water pipeline improvements for the Cross County Water Supply Corporation in McLennen and Bosque County, Texas.
Date:
August 6, 2007
Creator:
AR Consultants
Object Type:
Report
System:
The Portal to Texas History
An Archaeological Survey of the Proposed Indian Creek/Preston Road Subsystem Force Main Pipeline Improvements Route, Collin County, Texas
Report of archaeological survey findings regarding proposed sewer pipeline route to be constructed northwest of Plano in southwestern Collin County, Texas.
Date:
2007
Creator:
AR Consultants
Object Type:
Report
System:
The Portal to Texas History
Cultural Resources Survey Across Low Branch, Mansfield, Texas
Report of archaeological survey of proposed pipeline and lift station route in Mansfield, Texas.
Date:
2007
Creator:
AR Consultants
Object Type:
Report
System:
The Portal to Texas History
Cultural Resources Survey for Burlington Resources Oil & Gas Company's Coalson #3H-5H Well Pad Sites and Associated Pipeline Route Park County, Texas
Archaeological survey results of proposed pad well sites, access roads, and pipeline routes in Parker County, Texas.
Date:
2007
Creator:
AR Consultants
Object Type:
Report
System:
The Portal to Texas History
HANFORD REGULATORY EXPERIENCE REGULATION AT HANFORD A CASE STUDY
Hanford has played a pivotal role in the United States' defense for more than 60 years, beginning with the Manhattan Project in the 1940s. During its history, the Hanford Site has had nine reactors producing plutonium for the United States' nuclear weapons program. All the reactors were located next to the Columbia River and all had associated low-level radioactive and hazardous waste releases. Site cleanup, which formally began in 1989 with the signing of the Hanford Federal Facility Agreement and Consent Order, also known as the Tri-Party Agreement, involves more than 1,600 waste sites and burial grounds, and the demolition of more than 1,500buildings and structures, Cleanup is scheduled to be complete by 2035. Regulatory oversight of the cleanup is being performed by the U.S. Environmental Protection Agency (EPA) and the Washington State Department of Ecology(Ecology) under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) and the Revised Code of Washington, 'Hazardous Waste Management.' Cleanup of the waste sites and demolition of the many buildings and structures generates large volumes of contaminated soil, equipment, demolition debris, and other wastes that must be disposed of in a secure manner to prevent further environmental degradation. From a risk perspective, it is …
Date:
September 24, 2007
Creator:
AR, HAWKINS
Object Type:
Article
System:
The UNT Digital Library
FUTURE PLANS AT BNL: RHIC-II AND eRHIC.
The development of future facilities relevant to the study of deep inelastic scattering at BNL is described.
Date:
April 16, 2007
Creator:
ARONSON,S.
Object Type:
Article
System:
The UNT Digital Library
Alignment strategy for the ATLAS tracker
The ATLAS experiment is a multi-purpose particle detector that will study high-energy particle collisions produced by the Large Hadron Collider. For the reconstruction of charged particles, and their production and their decay vertices, ATLAS is equipped with a sophisticated tracking system, unprecedented in size and complexity. Full exploitation of both the Inner Detector and the muon spectrometer requires an accurate alignment. The challenge of aligning the ATLAS tracking devices is discussed, and the ATLAS alignment strategy is presented and illustrated with both data and Monte Carlo results.
Date:
September 23, 2007
Creator:
ATLAS & Golling, T.
Object Type:
Article
System:
The UNT Digital Library
ATLAS Inner Detector Event Data Model
The data model for event reconstruction (EDM) in the Inner Detector of the ATLAS experiment is presented. Different data classes represent evolving stages in the reconstruction data flow, and specific derived classes exist for the sub-detectors. The Inner Detector EDM also extends the data model for common tracking in ATLAS and is integrated into the modular design of the ATLAS high-level trigger and off-line software.
Date:
December 12, 2007
Creator:
ATLAS; Akesson, F.; Costa, M. J.; Dobos, D.; Elsing, M.; Fleischmann, S. et al.
Object Type:
Article
System:
The UNT Digital Library
Construction and Testing of a Low-power Cryostat for MARS
A low-power cryostat was designed and built for the Multi-sensor Airborne Radiation Survey (MARS) project for the purpose of housing a close-packed high-purity germanium (HPGe) detector array of 14 HPGe detectors. The power consumption of the cold mass in the cryostat was measured to be 4.07(11) watts, sufficient for 5.5 days of continuous operation using only 8 liters of liquid nitrogen. Temperatures throughout the cryostat were measured by platinum resistance temperature detectors. These measurements were used to determine the emissivity of the copper used in the floating radiation shield and outer cryostat wall, which was constructed using chemically cleaned and passivated copper metal. Using a PNNL-developed passivation process, an emissivity of 2.5(3)% was achieved for copper.
Date:
October 1, 2007
Creator:
Aalseth, Craig E.; Caggiano, Joseph A.; Day, Anthony R.; Fast, James E. & Fuller, Erin S.
Object Type:
Report
System:
The UNT Digital Library
Measurement of Lifetime and Decay-Width Difference in B0s -> J/psi phi Decays
The authors measure the mean lifetime, {tau} = 2/({Lambda}{sub L} + {Lambda}{sub H}), and the decay-width difference, {Delta}{Lambda} = {Lambda}{sub L} - {Lambda}{sub H}, of the light and heavy mass eigenstates of the B{sub s}{sup 0} meson, B{sub sL}{sup 0} and B{sub sH}{sup 0}, in B{sub s}{sup 0} {yields} J/{psi}{phi} decays using 1.7 fb{sup -1} of data collected with the CDF II detector at the Fermilab Tevatron p{bar p} collider. Assuming CP conservation, a good approximation for the B{sub s}{sup 0} system in the standard model, they obtain {Delta}{Lambda} = 0.076{sub -0.063}{sup +0.059}(stat.) {+-} 0.006(syst.) ps{sup -1} and {tau} = 1.52 {+-} 0.04(stat.) {+-} 0.02(syst.) ps, the most precise measurements to date. The constraints on the weak phase and {Delta}{Lambda} are consistent with CP conservation.
Date:
December 1, 2007
Creator:
Aaltonen, : T.
Object Type:
Article
System:
The UNT Digital Library
Measurement of the cross section for W-boson production in association with jets in ppbar collisions at s**(1/2) = 1.96-TeV
We present a measurement of the cross section for W-boson production in association with jets in p{bar p} collisions at {radical}s = 1.96 TeV. The analysis uses a data sample corresponding to an integrated luminosity of 320 pb{sup -1} collected with the CDF II detector. W bosons are identified in their electron decay channel and jets are reconstructed using a cone algorithm. For each W + {ge} n-jet sample (n = 1-4) we measure {sigma}(p{bar p} {yields} W + {ge} n-jet) x {Beta}(W {yields} e{nu}) with respect to the transverse energy E{sub T} of the nth-highest E{sub T} jet above 20 GeV, for a restricted W {yields} e{nu} decay phase space. The cross sections, corrected for all detector effects, can be directly compared to particle level W + jet(s) predictions. We present here comparisons to leading order and next-to-leading order predictions.
Date:
November 1, 2007
Creator:
Aaltonen, T.
Object Type:
Article
System:
The UNT Digital Library
Observation of the Decay B+-(c) ---> J/psi pi+- and Measurement of the B+-(c) Mass
The B{sub c}{sup {+-}} meson is observed through the decay B{sub c}{sup {+-}} {yields} J/{psi} {pi}{sup {+-}}, in data corresponding to an integrated luminosity of 2.4 fb{sup -1} recorded by the CDF II detector at the Fermilab Tevatron. A signal of 108 {+-} 15 candidates is observed, with a significance that exceeds 8{sigma}. The mass of the B{sub c}{sup {+-}} meson is measured to be 6275.6 {+-} 2.9(stat.) {+-} 2.5(syst.) MeV/c{sup 2}.
Date:
December 1, 2007
Creator:
Aaltonen, T.
Object Type:
Article
System:
The UNT Digital Library
Search for doubly charged Higgs bosons with lepton-flavour-violating decays involving tau leptons
The authors search for pair production of doubly charged Higgs particles (H{sup {+-}{+-}}) followed by decays into electron-tau (e{tau}) and muon-tau ({mu}{tau}) pairs using a data set corresponding to an integrated luminosity of 350 pb{sup -1} collected from {bar p}p collisions at {radical}s = 1.96 TeV by the CDF II experiment. They search separately for cases where three or four final-state leptons are detected, and then combine the results into limits for each exclusive flavor decay mode of the H{sup {+-}{+-}}. Assuming 100% branching ratios of the H{sup {+-}{+-}} to left-handed e{tau} ({mu}{tau}) pairs, they set an H{sup {+-}{+-}} lower mass limit of 114 (112) GeV/c{sup 2} at the 95% confidence level (C.L.).
Date:
December 1, 2007
Creator:
Aaltonen, T.
Object Type:
Article
System:
The UNT Digital Library