21 research outputs found
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Rationale for determining MCC spent fuel acquisitions
The Yucca Mountain Site Characterization Project of the US Department of Energy (DOE) is investigating the suitability of the Topopah Spring Tuff at Yucca Mountain, Nevada, for use as a disposal site for spent nuclear fuel and other high-level waste forms. The performance of the high-level waste forms and the engineered barrier system at the site must be shown to comply with the requirements in 10 CFR 60. Lawrence Livermore National Laboratory (LLNL) has the responsibility for determining the performance of the US commercial reactor spent nuclear fuels under potential repository conditions. Pacific Northwest Laboratory (PNL) performs testing of these highly radioactive materials in support of the LLNL program. This report summarizes the rationale for selecting additional spent fuels that should be acquired to support the LLNL and PNL testing programs. These programs have identified specific attributes that may affect spent fuel behavior in a repository
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Tritium permeation and related studies on barrier treated 316 stainless steel
To verify the performance of permeation-resistant cladding for tritium targets designed for a New Production Reactor Light Water Reactor, a tritium test facility was designed, developed, and certified. Testing is ongoing to verify the performance of reference designed targets. Accurate measurements were taken of tritium permeating from barrier-coated cladding specimens immersed in high-temperature autoclaves configured to simulate reactor coolant conditions. The tritium test pressure is controlled by heating a zirconium-alloy getter, previously charged with tritium, to a temperature that corresponds to a specified test pressure
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The pre-audit assessment: A homework assignment for auditors
The role of the quality assurance audit is evolving from compliance verification to a much broader assessment of programmatic and management performance. In the past, audits were poorly understood and caused fear and trepidation. Auditees turned an audit into a cat-and-mouse game using coverup strategies and decoy discrepancies. These games were meant to ``give the auditors what they want, namely a few findings that could later be easily corrected. At Pacific Northwest Laboratory (PNL), I observed auditing become a spectator sport. Matching a compliance-oriented auditor against a crafty group of scientists provided hours of entertainment. As a program manager, it was clear these games were neither productive useful nor cost effective. Fortunately, over the past few years several concepts embraced by ``total quality management` have begun to emerge at PNL. These concepts are being adopted by most successful organizations, and based on these concepts new tools and ideas are emerging to help organizations improve productivity and quality. Successful organizations have been and are continuing to develop management strategies that rely on participative approaches to their operations. These approaches encourage the empowerment of organization staff at all levels, with the goal of instilling ownership of quality in every staff member. As management philosophies are changing, so are the responsibilities and expectations of managers. Managers everywhere are experimenting with new tools to help them improve their operations and competitiveness. As the quality audit evolves, managers and other customers of the audit process have developed expectations for the auditing process that never existed in years past. These expectations have added complexity to the audit process. It is no longer adequate to prepare a checklist, perform the audit, and document the results. When viewed as a tool for verifying performance, a quality audit becomes more than a compliance checklist
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Drying Results of K-Basin Damaged/Corroded SNF Internal Sludge and Surface Coating
Experiments were performed using a thermogravimetric analysis (TGA) system by Pacific Northwest National Laboratory (PNNL)to study the drying behavior of the K-Basin spent nuclear fuel (SNF) internal sludge and two different surface coatings of SNF elements. These measurements were conducted in support of the safety and process analyses of the proposed Integrated Process Strategy (IPS) to move the N-Reactor fuel stored at K-Basin to an interim storage facility. These limited experiments on the corrosion products of K-Basin SNF material were part of the broad studies performed to ascertain the bounding pressurization of the Multi-Canister Overpack (MCO). Seven SNF internal sludge samples taken from different damage regions of three damaged/corroded outer K-Basin SNF elements were dried. Additionally, two surface coating samples taken from two SNF elements stored at K-West were tested. All the tests were performed in a vacuum atmosphere with the same temperature ramp rate of about 0.4 C/ min. Each TGA test sample was weighed before and after the test on a balance located in the Shielded Analytical Laboratory hot cell. The test samples were vacuum dried in the TGA system for about 24 hours prior to heating them at the rate of 0.4 C/min. The observations from the weight change data are summarized below
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Rationale for determining spent fuel acquisitions for repository testing
A rationale for selecting commercial spent nuclear fuels for use as testing materials for the Yucca Mountain Project was developed. A review of experimental data from fuel performance testing was conducted and performance-affecting attributes pertinent to storage and disposal conditions were identified. These were used to form the basis for a fuel-selection strategy designed to ensure adequate and representative samples are available for storage- and disposal-relevant testing
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Nuclear Energy Research Initiative. Development of a Stabilized Light Water Reactor Fuel Matrix for Extended Burnup
The main objective of this project is to develop an advanced fuel matrix capable of achieving extended burnup while improving safety margins and reliability for present operations. In the course of this project, the authors improve understanding of the mechanism for high burnup structure (HBS) formation and attempt to design a fuel to minimize its formation. The use of soluble dopants in the UO{sub 2} matrix to stabilize the matrix and minimize fuel-side corrosion of the cladding is the main focus
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System design description for the whole element furnace testing system
This document provides a detailed description of the Hanford Spent Nuclear Fuel (SNF) Whole Element Furnace Testing System located in the Postirradiation Testing Laboratory G-Cell (327 Building). Equipment specifications, system schematics, general operating modes, maintenance and calibration requirements, and other supporting information are provided in this document. This system was developed for performing cold vacuum drying and hot vacuum drying testing of whole N-Reactor fuel elements, which were sampled from the 105-K East and K West Basins. The proposed drying processes are intended to allow dry storage of the SNF for long periods of time. The furnace testing system is used to evaluate these processes by simulating drying sequences with a single fuel element and measuring key system parameters such as internal pressures, temperatures, moisture levels, and off-gas composition
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Characterization plan for Hanford spent nuclear fuel
Reprocessing of spent nuclear fuel (SNF) at the Hanford Site Plutonium-Uranium Extraction Plant (PUREX) was terminated in 1972. Since that time a significant quantity of N Reactor and Single-Pass Reactor SNF has been stored in the 100 Area K-East (KE) and K-West (KW) reactor basins. Approximately 80% of all US Department of Energy (DOE)-owned SNF resides at Hanford, the largest portion of which is in the water-filled KE and KW reactor basins. The basins were not designed for long-term storage of the SNF and it has become a priority to move the SNF to a more suitable location. As part of the project plan, SNF inventories will be chemically and physically characterized to provide information that will be used to resolve safety and technical issues for development of an environmentally benign and efficient extended interim storage and final disposition strategy for this defense production-reactor SNF
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Accelerated Characterization of Metal Fuel Stored in the Hanford K Basins
Efforts are under way to gather data on the condition of the metal fuel and associated sludge stored in the water-filled Hanford K Basins. Most of the current data gathering activities are being performed in the basins without fuel movement. These techniques include a video survey of open storage canisters, determination of water/gas levels in sealed canisters, sampling of gas and water from sealed canisters (for chemical analysis) and measurement of sludge depth and sludge volume
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Drying Results of K-Basin Fuel Element 2660M (Run 7)
The water-filled K-Basins in the Hanford 100 Area have been used to store N-Reactor spent nuclear fuel (SNF) since the 1970s. Because some leaks in the basin have been detected and some of the fuel is breached due to handling damage and corrosion, efforts are underway to remove the fuel elements from wet storage. An Integrated Process Strategy (IPS) has been developed to package, dry, transport, and store these metallic uranium fuel elements in an interim storage facility on the Hanford Site (WHC 1995). Information required to support the development of the drying processes, and the required safety analyses, is being obtained from characterization tests conducted on fuel elements removed from the K-Basins. A series of whole element drying tests (reported in separate documents, see Section 8.0) have been conducted by Pacific Northwest National Laboratory (PNNL) on several intact and damaged fuel elements recovered from both the K-East and K-West Basins. This report documents the results of the seventh of those tests, which was conducted on an N-Reactor outer fuel element removed from K-West canister 2660M. This element (referred to as Element 2660M) was stored underwater in the K-West Basin from 1983 until 1996. Element 2660M was subjected to a combination of low- and high-temperature vacuum drying treatments that were intended to mimic, wherever possible, the fuel treatment strategies of the IPS. The system used for the drying test was the Whole Element Furnace Testing System, described in Section 2.0, located in the Postirradiation Testing Laboratory (PTL, 327 Building). The test conditions and methodologies are given in Section 3.0. Inspections of the fuel element before and after the test are provided in Section 4.0. The experimental results are provided in Section 5.0, and discussed in Section 6.0