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open access

Instrumentation and operational requirements for pilot-scale CO/sub 2/ enhanced oil recovery projects

Description: This report describes an instrumentation system to monitor a miscible displacement pilot flood under carefully controlled conditions. The primary focus is on CO/sub 2/ flooding but the results apply equally well to other types of miscible floods. Included are discussions of the physical processes in a CO/sub 2/ flood, a review of existing CO/sub 2/ floods, instrumentation available, site selection and characterization, operation of the flood, simulator evaluation, and cost estimates for this ty… more
Date: June 1, 1980
Creator: Lyle, Jr., W. D. & Eisenhawer, S. W.
Partner: UNT Libraries Government Documents Department
open access

Probabilistic analysis of accidents involving pyrophoric particle accumulation in a closed system containing high explosives

Description: This paper describes a probabilistic analysis of an unusual safety concern encountered during safety analysis of a closed system containing high explosive (HE). In this application, a pyrophoric material could be generated inside the system by corrosion of system components. This pyrophoric may form extremely small particles that could be transported through a complex path to a high explosive component where they could collect on exposed surfaces as a result of routine handling operations. A po… more
Date: July 1997
Creator: Bott, T. F. & Eisenhawer, S. W.
Partner: UNT Libraries Government Documents Department
open access

Including uncertainty in hazard analysis through fuzzy measures

Description: This paper presents a method for capturing the uncertainty expressed by an Hazard Analysis (HA) expert team when estimating the frequencies and consequences of accident sequences and provides a sound mathematical framework for propagating this uncertainty to the risk estimates for these accident sequences. The uncertainty is readily expressed as distributions that can visually aid the analyst in determining the extent and source of risk uncertainty in HA accident sequences. The results also can… more
Date: December 1, 1997
Creator: Bott, T.F. & Eisenhawer, S.W.
Partner: UNT Libraries Government Documents Department
open access

Initiating-event frequencies for nuclear weapons dismantlement hazard analysis

Description: A quantitative data base for initiating events encountered during nuclear weapons handling is described. This data base was assembled from incident reports at the plant where the weapons are handled. The strengths and pitfalls of constructing such a data base are elaborated using examples encountered in the data. Insights gained into accident sequences, human error probabilities, and other areas of concern are discussed.
Date: August 1, 1996
Creator: Eisenhawer, S.W. & Bott, T.F.
Partner: UNT Libraries Government Documents Department
open access

Accident reconstruction using process trees

Description: A study conducted by Pittsburgh Energy Technology Center of sulfur emissions from about 1,300 United States coal-fired utility boilers indicated that half of the emissions were the result of burning coals having greater than 1.2 pounds of SO{sub 2} per million BTU. This was mainly attributed to the high pyritic sulfur content of the boiler fuel. A significant reduction in SO{sub 2} emissions could be accomplished by removing the pyrite from the coals by advanced physical fine coal cleaning. An … more
Date: July 1, 1995
Creator: Eisenhawer, S.W. & Bott, T.F.
Partner: UNT Libraries Government Documents Department
open access

A hazards analysis of a nuclear explosives dismantlement

Description: This paper describes the methodology used in a quantitative hazard assessment of a nuclear weapon disassembly process. Potential accident sequences were identified using an accident-sequence fault tree based on operational history, weapon safety studies, a hazard analysis team composed of weapons experts, and walkthroughs of the process. The experts provided an initial screening of the accident sequences to reduce the number of accident sequences that would be quantified. The accident sequences… more
Date: July 1, 1995
Creator: Bott, T.F. & Eisenhawer, S.W.
Partner: UNT Libraries Government Documents Department
open access

System to evaluate the performance of insulated tubulars in steam injection wells

Description: The efficiency of a thermal enhanced oil recovery project with surface steam generation can be significantly increased by using insulated tubing in the injection wells. In order to evaluate the performance of various insulated tubulars it is necessary to obtain detailed temperature measurements and accurate heat loss data under actual in-field conditions. A system to provide this information has been developed and is in operation at the Aberfeldy steam pilot near Lloydminster, Saskatchewan, Can… more
Date: January 1, 1981
Creator: Eisenhawer, S. W.; Johnson, D. R. & Vigil, W.J.
Partner: UNT Libraries Government Documents Department
open access

Evaluation of high-level waste pretreatment processes with an approximate reasoning model

Description: The development of an approximate-reasoning (AR)-based model to analyze pretreatment options for high-level waste is presented. AR methods are used to emulate the processes used by experts in arriving at a judgment. In this paper, the authors first consider two specific issues in applying AR to the analysis of pretreatment options. They examine how to combine quantitative and qualitative evidence to infer the acceptability of a process result using the example of cesium content in low-level was… more
Date: April 1, 1999
Creator: Bott, T.F.; Eisenhawer, S.W. & Agnew, S.F.
Partner: UNT Libraries Government Documents Department
open access

Probabilistic modeling of propagating explosions

Description: Weapons containing significant quantities of high explosives (HE) are sometimes located in close proximity to one another. If an explosion occurs in a weapon, the possibility of propagation to one or more additional weapons may exist, with severe consequences possibly resulting. In the general case, a system of concern consists of multiple weapons and various other objects in a complex, three-dimensional geometry. In each weapon, HE is enclosed by (casing) materials that function as protection … more
Date: March 1, 1996
Creator: Luck, L.B.; Eisenhawer, S.W. & Bott, T.F.
Partner: UNT Libraries Government Documents Department
open access

Analysis of propagating explosions

Description: Weapons are often in close proximity to one another during transport or storage. If one weapon explodes, there is a possibility that the fragments generated will initiate a subsequent explosion in one or more neighboring weapons. Propagating explosions of this sort have the potential for severe consequences either because of the total amount of explosives that react or because the response of individual weapons may be particularly energetic. In this paper, we consider a well-defined problem in … more
Date: July 1, 1996
Creator: Luck, L.B.; Eisenhawer, S.W. & Bott, T.F.
Partner: UNT Libraries Government Documents Department
open access

Detonation probabilities of high explosives

Description: The probability of a high explosive violent reaction (HEVR) following various events is an extremely important aspect of estimating accident-sequence frequency for nuclear weapons dismantlement. In this paper, we describe the development of response curves for insults to PBX 9404, a conventional high-performance explosive used in US weapons. The insults during dismantlement include drops of high explosive (HE), strikes of tools and components on HE, and abrasion of the explosive. In the case of… more
Date: July 1, 1995
Creator: Eisenhawer, S.W.; Bott, T.F. & Bement, T.R.
Partner: UNT Libraries Government Documents Department
open access

Resource allocation using risk analysis

Description: Allocating limited resources among competing priorities is an important problem in management. In this paper we describe an approach to resource allocation using risk as a metric. We call this approach the Logic-Evolved Decision (LED) approach because we use logic-models to generate an exhaustive set of competing options and to describe the often highly complex model used for evaluating the risk reduction achieved by different resource allocations among these options. The risk evaluation then p… more
Date: January 1, 2003
Creator: Bott, T. F. (Terrence F.) & Eisenhawer, S. W. (Stephen W.)
Partner: UNT Libraries Government Documents Department
open access

Analysis of lightning-related risk in outdoor high explosive research.

Description: The behavior of materials at high strain rates can be studied using high explosives (HE) as an energy source. Such hydrodynamic experiments may be performed on full-scale systems, requiring kilogram quantities of HE and therefore are performed at outdoor facilities. One such facility is DARHT-the Dual-Axis Radiographic Hydrodynamic Test facility located at Los Alamos National Laboratory in northern New Mexico. DARHT is a very large flash x-ray machine. The high-intensity, short-duration x-ray p… more
Date: January 1, 2002
Creator: Eisenhawer, S. W. (Stephen W.) & Bott, T. F. (Terrence F.)
Partner: UNT Libraries Government Documents Department
open access

A logic model approach to conceptual design of a scientific/industrial complex.

Description: The development of a large-scale scientific/industrial complex is a difficult undertaking. At the conceptual design stage a number of issues must be carefully resolved for the project to be successful. A few of these questions include: What is the purpose of the complex? What capabilities are needed to express this purpose? How should the facilities that contain these capabilities be arranged and in what order should they be constructed? Which capabilities are most important in fulfilling the c… more
Date: January 1, 2001
Creator: Bott, T. F. (Terrence F.) & Eisenhawer, S. W. (Stephen W.)
Partner: UNT Libraries Government Documents Department
open access

A risk-based approach to designing effective security force training exercises

Description: The effectiveness of a security force in protecting a nuclear facility is often evaluated using training exercises that pit a group of simulated attackers against a security team. In the situation studied here, a security force was regularly tested by a regulatory body with the responsibility for security oversight. It was observed that the regulators were continually imposing more challenging security scenarios by assigning increasingly sophisticated facility knowledge to the attackers. Not su… more
Date: January 1, 2002
Creator: Bott, T. F. (Terrence F.) & Eisenhawer, S. W. (Stephen W.)
Partner: UNT Libraries Government Documents Department
open access

System reliability assessment with an approximate reasoning model

Description: The projected service life of weapons in the US nuclear stockpile will exceed the original design life of their critical components. Interim metrics are needed to describe weapon states for use in simulation models of the nuclear weapons complex. The authors present an approach to this problem based upon the theory of approximate reasoning (AR) that allows meaningful assessments to be made in an environment where reliability models are incomplete. AR models are designed to emulate the inference… more
Date: December 1998
Creator: Eisenhawer, S. W.; Bott, T. F.; Helm, T. M. & Boerigter, S. T.
Partner: UNT Libraries Government Documents Department
open access

An approximate-reasoning-based method for screening high-level waste tanks for flammable gas

Description: The in situ retention of flammable gas produced by radiolysis and thermal decomposition in high-level waste can pose a safety problem if the gases are released episodically into the dome space of a storage tank. Screening efforts at Hanford have been directed at identifying tanks in which this situation could exist. Problems encountered in screening motivated an effort to develop an improved screening methodology. Approximate reasoning (AR) is a formalism designed to emulate the kinds of comple… more
Date: July 1, 1998
Creator: Eisenhawer, S.W.; Bott, T.F. & Smith, R.E.
Partner: UNT Libraries Government Documents Department
open access

Uncertainty and approximate reasoning in waste pretreatment planning

Description: Waste pretreatment process planning within the DOE complex must consider many different outcomes in order to perform the tradeoffs necessary to accomplish this important national mission. One of the difficulties encountered by many who assess these tradeoffs is that the complexity of this problem taxes the abilities of any single person or small group of individuals. For example, uncertainties in waste composition as well as process efficiency are well known yet incompletely considered in the s… more
Date: November 1, 1998
Creator: Agnew, S.F.; Eisenhawer, S.W. & Bott, T.F.
Partner: UNT Libraries Government Documents Department
open access

Use of hazard assessments to achieve risk reduction in the USDOE Stockpile Stewardship (SS-21) Program

Description: This paper summarizes the nuclear explosive hazard assessment activities performed to support US Department of Energy (DOE) Stockpile Stewardship Demonstration Project SS-21, better known as the ``Seamless Safety`` program. Past practice within the DOE Complex has dictated the use of a significant number of post-design/fabrication safety reviews to analyze the safety associated with operations on nuclear explosives and to answer safety questions. These practices have focused on reviewing-in or … more
Date: July 1, 1995
Creator: Fischer, S.R.; Konkel, H.; Bott, T.; Eisenhawer, S.W.; DeYoung, L. & Hockert, J.
Partner: UNT Libraries Government Documents Department
open access

An approximate-reasoning-based method for screening flammable gas tanks

Description: High-level waste (HLW) produces flammable gases as a result of radiolysis and thermal decomposition of organics. Under certain conditions, these gases can accumulate within the waste for extended periods and then be released quickly into the dome space of the storage tank. As part of the effort to reduce the safety concerns associated with flammable gas in HLW tanks at Hanford, a flammable gas watch list (FGWL) has been established. Inclusion on the FGWL is based on criteria intended to measure… more
Date: March 1, 1998
Creator: Eisenhawer, S.W.; Bott, T.F. & Smith, R.E.
Partner: UNT Libraries Government Documents Department
open access

An evaluation of the effectiveness of the US Department of Energy Integrated Safety Process (SS-21) for Nuclear Explosive Operations using quantitative hazard analysis

Description: This paper evaluates the effectiveness of the US Department of Energy Integrated Safety Process or ``Seamless Safety (SS-21)`` program for reducing risk associated with nuclear explosive operations. A key element in the Integrated Safety Process is the use of hazard assessment techniques to evaluate process design changes in parallel or concurrently with process design and development. This concurrent hazard assessment method recently was employed for the B61-0, 2 & 5 and W69 nuclear explosive … more
Date: March 1, 1996
Creator: Fischer, S.R.; Konkel, H.; Bott, T.; Eisenhawer, S.; Auflick, J.; Houghton, K. et al.
Partner: UNT Libraries Government Documents Department
open access

Project DEEP STEAM: Fourth Meeting of the Technical Advisory Panel, Albuquerque, NM, November 1980

Description: The Fourth Project DEEP STEAM Technical Advisory Panel Meeting was held on 5 and 6 November 1980 in Albuquerque, New Mexico, to review the status of project DEEP STEAM. This Proceedings, following the order of the meeting, is divided into five main sections: the injection string modification program, the downhole steam generator program, supporting activities, field testing, and the Advisory Panel recommendations and discussion. Each of the 17 presentations is summarized, and a final Discussion… more
Date: July 1, 1981
Creator: Fox, R. L.; Donaldson, A. B.; Eisenhawer, S. W.; Hart, C. M.; Johnson, D. R.; Mulac, A. J. et al.
Partner: UNT Libraries Government Documents Department
open access

A logic model for cook-off phenomenology in high explosives

Description: Logic models are valuable tools in the development of predictive models for complex physical processes. The use of deductive logic in the form of a possibility tree makes it straightforward to develop a comprehensive set of unique, alternative paths that describe the system. We demonstrate the power of this approach for the complex process of cook-off of high explosives (HE). The possibility tree describes the causal paths from heating HE to the alternative end states. One of these end states i… more
Date: January 1, 2003
Creator: Eisenhawer, S. W. (Stephen W.); Bott, T. F. (Terrence F.); Luck, L. B.; Kingson, J. & Key, B. P. (Brian P.)
Partner: UNT Libraries Government Documents Department
open access

Safety support for hydrogen reanalysis of Waste Tank 101-SY

Description: Tank 101-Sy, a double-shell tank on the Hanford SY high-level waste tank farm, has periodic releases of large volumes of gas. The released gas contains hydrogen (a fuel), nitrous oxide (a strong oxidizer), and other gases. These gases are intimately mixed, and therefore, it is very difficult to reduce the potential for a hydrogen combustion event. The safety is hydrogen gas exceeding one-quarter of the Lower Flammability Limit during these periodic releases. The Department of Energy Office of E… more
Date: December 31, 1991
Creator: Sullivan, L. H.; Eisenhawer, S. W.; Henninger, R. J.; Hill, S. W.; MacFarlane, D. R.; Nichols, B. D. et al.
Partner: UNT Libraries Government Documents Department
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