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Preliminary results of thermal igniter experiments in H/sub 2/-air-steam environments. [PWR; BWR]

Description: Thermal igniters (glow plugs), proposed by the Tennessee Valley Authority for intentional ignition of hydrogen in nuclear reactor containment, have been tested for functionability in mixtures of air, hydrogen, and steam. Test environments included 6% to 16% hydrogen concentrations in air, and 8%, 10%, and 12% hydrogen in mixtures with 30% and 40% steam fractions. All were conducted in a 10.6 ft/sup 3/ insulated pressure vessel. For all of these tests the glow plug successfully initiated combustion. Dry air/hydrogen tests exhibited a distinct tendency for complete combustion at hydrogen concentrations between 8% and 9%. Steam suppressed both peak pressures and completeness of combustion. No combustion could be initiated at or above a 50% steam fraction. Circulation of the mixture with a fan increased the completeness of combustion. The glow plug showed no evidence of performance degradation throughout the program.
Date: January 1, 1981
Creator: Lowry, W.
Partner: UNT Libraries Government Documents Department

Engineered Barrier Systems Thermal-Hydraulic-Chemical Column Test Report

Description: The Engineered Barrier System (EBS) Thermal-Hydraulic-Chemical (THC) Column Tests provide data needed for model validation. The EBS Degradation, Flow, and Transport Process Modeling Report (PMR) will be based on supporting models for in-drift THC coupled processes, and the in-drift physical and chemical environment. These models describe the complex chemical interaction of EBS materials, including granular materials, with the thermal and hydrologic conditions that will be present in the repository emplacement drifts. Of particular interest are the coupled processes that result in mineral and salt dissolution/precipitation in the EBS environment. Test data are needed for thermal, hydrologic, and geochemical model validation and to support selection of introduced materials (CRWMS M&O 1999c). These column tests evaluated granular crushed tuff as potential invert ballast or backfill material, under accelerated thermal and hydrologic environments. The objectives of the THC column testing are to: (1) Characterize THC coupled processes that could affect performance of EBS components, particularly the magnitude of permeability reduction (increases or decreases), the nature of minerals produced, and chemical fractionation (i.e., concentrative separation of salts and minerals due to boiling-point elevation). (2) Generate data for validating THC predictive models that will support the EBS Degradation, Flow, and Transport PMR, Rev. 01.
Date: December 13, 2001
Creator: Lowry, W. E.
Partner: UNT Libraries Government Documents Department

Characterization of radioactive contamination inside pipes with the Pipe Explorer{trademark} system

Description: The objective for the development of the Pipe Explorer{trademark} radiological characterization system is to achieve a cost effective, low risk means of characterizing gamma radioactivity on the inside surface of pipes. The unique feature of this inspection system is the use of a pneumatically inflated impermeable membrane which transports the detector into the pipe as it inverts. The membrane`s internal air pressure tows the detector and tether through the pipe. This mechanism isolates the detector and its cabling from the contaminated surface, yet allows measurement of radioactive emissions which can readily penetrate the thin plastic membrane material (such as gamma and high energy beta emissions). In Phase 1, an initial survey of DOE facilities was conducted to determine the physical and radiological characteristics of piping systems. The inverting membrane deployment system was designed and extensively tested in the laboratory. A range of membrane materials was tested to evaluate their ruggedness and deployment characteristics. Two different sizes of gamma scintillation detectors were procured and tested with calibrated sources. Radiation transport modeling evaluated the measurement system`s sensitivity to detector position relative to the contaminated surface, the distribution of the contamination, background gamma levels, and gamma source energy levels. In the culmination of Phase 1, a field demonstration was conducted at the Idaho National Engineering Laboratory`s Idaho Chemical Processing Plant. The project is currently in transition from Phase 1 to Phase 2, where more extensive demonstrations will occur at several sites. Results to date are discussed.
Date: December 31, 1994
Creator: Lowry, W.
Partner: UNT Libraries Government Documents Department

Three-dimensional thermal analysis of a baseline spent fuel repository

Description: A three-dimensional thermal analysis has been performed using finite difference techniques to determine the near-field response of a baseline spent fuel repository in a deep geologic salt medium. A baseline design incorporates previous thermal modeling experience and OWI recommendations for areal thermal loading in specifying the waste form properties, package details, and emplacement configuration. The base case in this thermal analysis considers one 10-year old PWR spent fuel assembly emplaced to yield a 36 kw/acre (8.9 w/m/sup 2/) loading. A unit cell model in an infinite array is used to simplify the problem and provide upper-bound temperatures. Boundary conditions are imposed which allow simulations to 1000 years. Variations studied include a comparison of ventilated and unventilated storage room conditions, emplacement packages with and without air gaps surrounding the canister, and room cool-down scenarios with ventilation following an unventilated state for retrieval purposes. At this low power level ventilating the emplacement room has an immediate cooling influence on the canister and effectively maintains the emplacement room floor near the temperature of the ventilating air. The annular gap separating the canister and sleeve causes the peak temperature of the canister surface to rise by 10/sup 0/F (5.6/sup 0/C) over that from a no gap case assuming perfect thermal contact. It was also shown that the time required for the emplacement room to cool down to 100/sup 0/F (38/sup 0/C) from an unventilated state ranged from 2 weeks to 6 months; when ventilation initiated after times of 5 years to 50 years, respectively. As the work was performed for the Nuclear Regulatory Commission, these results provide a significant addition to the regulatory data base for spent fuel performance in a geologic repository.
Date: June 5, 1980
Creator: Altenbach, T.J. & Lowry, W.E.
Partner: UNT Libraries Government Documents Department

Advanced three-dimensional thermal modeling of a baseline spent fuel repository

Description: A three-dimensional thermal analysis using finite difference techniques was performed to determine the near-field response of a baseline spent fuel repository in a deep geologic salt medium. A baseline design incorporates previous thermal modeling experience and OWI recommendations for areal thermal loading in specifying the waste form properties, package details, and emplacement configuration. The base case in this thermal analysis considers one 10-year old PWR spent fuel assembly emplaced to yield a 36 kW/acre (8.9 W/m/sup 2/) loading. A unit cell model in an infinite array is used to simplify the problem and provide upper-bound temperatures. Boundary conditions are imposed which allow simulations to 1000 years. Variations studied include a comparison of ventilated and unventilated storage room conditions, emplacement packages with and without air gaps surrounding the canister, and room cool-down scenarios with ventilation following an unventilated state for retrieval purposes. It was found that at this low-power level, ventilating the emplacement room has an immediate cooling influence on the canister and effectively maintains the emplacement room floor near the temperature of the ventilating air.
Date: April 29, 1980
Creator: Altenbach, T.J. & Lowry, W.E.
Partner: UNT Libraries Government Documents Department

Effects of annular air gaps surrounding an emplaced nuclear waste canister in deep geologic storage

Description: Annular air spaces surrounding an emplaced nuclear waste canister in deep geologic storage will have significant effects on the long-term performance of the waste form. Addressed specifically in this analysis is the influence of a gap on the thermal response of the waste package. Three dimensional numerical modeling predicts temperature effects for a series of parameter variations, including the influence of gap size, surface emissivities, initial thermal power generation of the canister, and the presence/absence of a sleeve. Particular emphasis is placed on determining the effects these variables have on the canister surface temperature. We have identified critical gap sizes at which the peak transient temperature occurs when gap widths are varied for a range of power levels. It is also shown that high emissivities for the heat exchanging surfaces are desirable, while that of the canister surface has the greatest influence. Gap effects are more pronounced, and therefore more effort should be devoted to optimal design, in situations where the absolute temperature of the near field medium is high. This occurs for higher power level emplacements and in geomedia with low thermal conductivities. Finally, loosely inserting a sleeve in the borehole effectively creates two gaps and drastically raises the canister peak temperature. It is possible to use these results in the design of an optimum package configuration which will maintain the canister at acceptable temperature levels. A discussion is provided which relates these findings to NRC regulatory considerations.
Date: June 5, 1980
Creator: Lowry, W.E.; Davis, B.W. & Cheung, H.
Partner: UNT Libraries Government Documents Department

Annular air space effects on nuclear waste canister temperatures in a deep geologic waste repository

Description: Air spaces in a deep geologic repository for nuclear high level waste will have an important effect on the long-term performance of the waste package. The important temperature effects of an annular air gap surrounding a high level waste canister are determined through 3-D numerical modeling. Air gap properties and parameters specifically analyzed and presented are the air gap size, surfaces emissivity, presence of a sleeve, and initial thermal power generation rate; particular emphasis was placed on determining the effect of these variables have on the canister surface temperature. Finally a discussion based on modeling results is presented which specifically relates the results to NRC regulatory considerations.
Date: May 13, 1980
Creator: Lowry, W.E.; Cheung, H. & Davis, B.W.
Partner: UNT Libraries Government Documents Department

Alpha detection in pipes using an inverting membrane scintillator

Description: Characterization of surface alpha emitting contamination inside enclosed spaces such as piping systems presents an interesting radiological measurement challenge. Detection of these alpha particles from the exterior of the pipe is impossible since the alpha particles are completely absorbed by the pipe wall. Traditional survey techniques, using hand-held instruments, simply can not be used effectively inside pipes. Science and Engineering Associates, Inc. is currently developing an enhancement to its Pipe Explorer{trademark} system that will address this challenge. The Pipe Explorer{trademark} uses a unique sensor deployment method where an inverted tubular membrane is propagated through complex pipe runs via air pressure. The inversion process causes the membrane to fold out against the pipe wall, such that no part of the membrane drags along the pipe wall. This deployment methodology has been successfully demonstrated at several DOE sites to transport specially designed beta and gamma scintillation detectors into pipes ranging in length up to 250 ft. The measurement methodology under development overcomes the limitations associated with conventional hand-held survey instruments by remotely emplacing an alpha scintillator in direct contact with the interior pipe surface over the entire length to be characterized. This is accomplished by incorporating a suitable scintillator into the otherwise clear membrane material. Alpha particles emitted from the interior pipe surface will intersect the membrane, resulting in the emission of light pulses from the scintillator. A photodetector, towed by the inverting membrane, is used to count these light pulses as a function of distance into the pipe, thereby producing a log of the surface alpha contamination levels. It is anticipated that the resulting system will be able to perform measurements in pipes as small as two inches in diameter, and several hundred feet in length.
Date: December 31, 1995
Creator: Kendrick, D.T.; Cremer, C.D.; Lowry, W. & Cramer, E.
Partner: UNT Libraries Government Documents Department

Barometric pumping with a twist: VOC containment and remediation without boreholes

Description: Objectives of Phase I (completed Nov. 1995) was to evaluate the feasibility of applying surface sealing and venting features to contain and remediate volatile organic compound (VOC) contaminated soils in the vadose zone. In Phase II, the remediation system will be installed at the Radioactive Waste Management Complex of INEL. It will cover an area of the landfill known to be contaminated with chlorinated hydrocarbons, deposited in shallow trenches. Operation will be monitored for 12 to 18 months to evaluate the impact on soil gas displacement. The 4 key components are the surface seal, plenum, vent assembly, and soil vapor monitoring points.
Date: December 31, 1996
Creator: Lowry, W.; Dunn, S.D. & Neeper, D.
Partner: UNT Libraries Government Documents Department

Laboratory evaluation of the Pipe Explorer{trademark} gamma measurement and deployment capability

Description: The DOE is faced with the responsibility of decommissioning and dismantling many of its nuclear process facilities. Much of this will involve piping systems which may or may not be contaminated with radioactive material. It is important to be able to differentiate contaminated from non-contaminated material, since the disposal costs for radioactive waste are significant (on the order of hundreds of dollars per cubic foot). In the case of pipes, this determination may be particularly difficult if the pipes are not easily accessible. As a solution to this problem, SEA is developing an inverting membrane technology, called Pipe Explorer{trademark} which uses commercial gamma spectroscopy systems to characterize the radiation levels inside of pipes. The heart of the system is an air-tight membrane which is initially spooled inside of a canister. The end of the membrane protruding out of the canister is folded over and attached to a basepipe. With this configuration, when the canister becomes pressurized the pressure force on the membrane causes the membrane to be pulled from the spool. This continues until the membrane is completely off the spool. A radiation detector is attached to the end of the membrane and towed into the pipe as the membrane continues to evert. The detector cabling is also towed into the pipe. To retrieve the system from a pipe the process is simply reversed, where the cabling, detector, and membrane are wound back onto the spool. The system can thus be used to move a detector freely back and forth through a pipe to provide high resolution analysis of the location of radioactive contamination in pipes. This unique method can deploy the detector and analyze piping systems with multiple elbows and vertical runs. The membrane also serves to protect the expensive detector from contamination.
Date: August 1, 1994
Creator: Cremer, C.D.; Cramer, E. & Lowry, W.
Partner: UNT Libraries Government Documents Department

In-situ permeability measurements with direct push techniques: Phase II topical report

Description: This effort designed, fabricated, and field tested the engineering prototype of the Cone Permeameter{trademark} system. The integrated system includes the instrumented penetrometer probe, air and water pumps, flowrate controls, flow sensors, and a laptop-controlled data system. All of the equipment is portable and can be transported as luggage on airlines. The data system acquired and displays the process measurements (pressures, flows, and downhole temperature) in real time and calculates the resulting permeability. The measurement probe is a 2 inch diameter CPT rod section, incorporating a screened injection zone near the lower end of the rod and multiple sensitive absolute pressure sensors embedded in the probe at varying distances from the injection zone. Laboratory tests in a large test cell demonstrated the system's ability to measure nominally 1 Darcy permeability soil (30 to 40 Darcy material had been successfully measured in the Phase 1 effort). These tests also provided a shakedown of the system and identified minor instrument problems, which were resolved. Supplemental numerical modeling was conducted to evaluate the effects of layered permeability (heterogeneity) and anisotropy on the measurement system's performance. The general results of the analysis were that the Cone Permeameter could measure accurately, in heterogeneous media, the volume represented by the sample port radii if the outer pressure ports were used. Anisotropic permeability, while readily analyzed numerically, is more complicated to resolve with the simple analytical approach of the 1-D model, and will need further work to quantify. This phase culminated in field demonstrations at the DOE Savannah River Site. Saturated hydraulic conductivity measurements were completed at the D-Area Coal Pile Runoff Basin, and air permeability measurements were conducted at the M Area Integrated Demonstration Site and the 321 M area. The saturated hydraulic conductivity measurements were the most successful and compared well to relevant existing data. Air ...
Date: March 1, 1999
Creator: Lowry, W.; Mason, N.; Chipman, V.; Kisiel, K. & Stockton, J.
Partner: UNT Libraries Government Documents Department

Characterization of radioactive contamination inside pipes with the Pipe Explorer{trademark} system

Description: The U.S. Department of Energy`s nuclear facility decommissioning program needs to characterize radiological contamination inside piping systems before the pipe can be recycled, remediated, or disposed. Science and Engineering associates, Inc. under contract with the DOE Morgantown Energy Technology Center has developed and demonstrated the Pipe Explorer{trademark} system, which uses an inverting membrane to transport various characterization sensors into pipes. The basic process involves inverting (turning inside out) a tubular impermeable membrane under air pressure. A characterization sensor is towed down the interior of the pipe by the membrane. Advantages of this approach include the capability of deploying through constrictions in the pipe, around 90{degrees} bends, vertically up and down, and in slippery conditions. Because the detector is transported inside the membrane (which is inexpensive and disposable), it is protected from contamination, which eliminates cross-contamination. Characterization sensors that have been demonstrated with the system thus far include: gamma detectors, beta detectors, video cameras, and pipe locators. Alpha measurement capability is currently under development. A remotely operable Pipe Explorer{trademark} system has been developed and demonstrated for use in DOE facilities in the decommissioning stage. The system is capable of deployment in pipes as small as 2-inch-diameter and up to 250 feet long. This paper describes the technology and presents measurement results of a field demonstration conducted with the Pipe Explorer{trademark} system at a DOE site. These measurements identify surface activity levels of U-238 contamination as a function of location in drain lines. Cost savings to the DOE of approximately $1.5 million dollars were realized from this one demonstration.
Date: December 31, 1995
Creator: Kendrick, D.T.; Cremer, C.D.; Lowry, W. & Cramer, E.
Partner: UNT Libraries Government Documents Department

Barometric pumping with a twist: VOC containment and remediation without boreholes

Description: A large national cost is incurred in remediating near-surface contamination such as surface spills, leaking buried pipelines, and underground storage tank sites. Many of these sites can be contained and remediated using enhanced natural venting, capitalizing on barometric pumping. Barometric pumping is the cyclic movement experienced by soil gas due to oscillations in atmospheric pressure. Daily variations of 5 millibars are typical, while changes of 25 to 50 millibars can occur due to major weather front passage. The fluctuations can cause bulk vertical movement in soil gas ranging from centimeters to meters, depending on the amplitude of the pressure oscillation, soil gas permeability, and depth to an impermeable boundary such as the water table. Since the bulk gas movement is cyclic, under natural conditions no net advective vertical movement occurs over time. Science and Engineering Associates, Inc., is developing an engineered system to capitalize on the oscillatory flow for soil contaminant remediation and containment. By design, the system allows normal upward movement of soil gas but restricts the downward movement during barometric highs. The earth`s surface is modified with a sealant and vent valve such that the soil gas flow is literally {open_quotes}ratcheted{close_quotes} to cause a net upward flow over time. A key feature of the design is that it does not require boreholes, resulting in a very low cost remediation effort and reduced personnel exposure risk. In the current phase (Phase I) the system`s performance is being evaluated. Static and transient analysis results are presented which illustrate the relative magnitude of this advective movement compared to downward contaminant diffusion rates. Calculations also indicate the depth of influence for various surface and soil configurations. The system design will be presented, as well as a cost assessment compared to conventional techniques.
Date: December 31, 1995
Creator: Lowry, W.; Dunn, S.D.; Walsh, R. & Zakian, P.
Partner: UNT Libraries Government Documents Department

SEAMIST{trademark} in-situ instrumentation and vapor sampling system applications in the Sandia Mixed Waste Landfill Integrated Demonstration program: Final report

Description: The Mixed Waste Landfill Integrated Demonstration was tasked with demonstrating innovative technologies for the cleanup of chemical and mixed waste landfills that are representive of sites occurring throughout the DOE complex and the nation. The SEAMIST{trademark} inverting membrane deployment system has been used successfully at the Mixed Waste Landfill Integrated Demonstration (MWLID) for multipoint vapor sampling, pressure measurement, permeability measurement, sensor integration demonstrations, and borehole lining. Several instruments were deployed inside the SEAMIST{trademark}-lined boreholes to detect metals, radionuclides, moisture, and geologic variations. The liner protected the instruments from contamination, maintained support of the uncased borehole wall, and sealed the total borehole from air circulation. Recent activities included the installation of three multipoint vapor sampling systems and sensor integration systems in 100-foot-deep vertical boreholes. A long term pressure monitoring program has recorded barometric pressure effects at depth with relatively high spatial resolution. The SEAMIST{trademark} system has been integrated with a variety of hydrologic and chemical sensors for in-situ measurements, demonstrating its versatility as an instrument deployment system that allows easy emplacement and removal. Standard SEAMIST{trademark} vapor sampling systems were also integrated with state-of-the-art volatile organic compound analysis technologies. The results and status of these demonstration tests are presented.
Date: September 1, 1995
Creator: Williams, C.; Lowry, W.; Cremer, D. & Dunn, S.D.
Partner: UNT Libraries Government Documents Department

Characterization of radioactive contamination inside pipes with the Pipe Explorer{trademark} system. Final report

Description: The Department of Energy (DOE) is currently in the process of decommissioning and dismantling many of its nuclear materials processing facilities that have been in use for several decades. Site managers throughout the DOE complex must employ the safest and most cost effective means to characterize, remediate and recycle or dispose of hundreds of miles of potentially contaminated piping and duct work. The DOE discovered that standard characterization methods were inadequate for its pipes, drains, and ducts because many of the systems are buried or encased. In response to the DOE`s need for a more specialized characterization technique, Science and Engineering Associates, Inc. (SEA) developed the Pipe Explorer{trademark} system through a DOE Office of Science and Technology (OST) contract administered through the Federal Energy Technology Center (FETC). The purpose of this report is to serve as a comprehensive overview of all phases of the Pipe Explorer{trademark} development project. The report is divided into 6 sections. Section 2 of the report provides an overview of the Pipe Explorer{trademark} system, including the operating principles of using an inverting membrane to tow sensors into pipes. The basic components of the characterization system are also described. Descriptions of the various deployment systems are given in Section 3 along with descriptions of the capabilities of the deployment systems. During the course of the development project 7 types of survey instruments were demonstrated with the Pipe Explorer{trademark} and are a part of the basic toolbox of instruments available for use with the system. These survey tools are described in Section 4 along with their typical performance specifications. The 4 demonstrations of the system are described chronologically in Section 5. The report concludes with a summary of the history, status, and future of the Pipe Explorer{trademark} system in Section 6.
Date: September 30, 1997
Creator: Cremer, C.D.; Kendrick, D.T.; Lowry, W. & Cramer, E.
Partner: UNT Libraries Government Documents Department

Busted Butte Unsaturated Zone Transport Test: Fiscal Year 1998 Status Report Yucca Mountain Site Characterization Program Deliverable SPU85M4

Description: This report describes the status of the Busted Butte Unsaturated Zone Transport Test (UZTT) and documents the progress of construction activities and site and laboratory characterization activities undertaken in fiscal year 1998. Also presented are predictive flow-and-transport simulations for Test Phases 1 and 2 of testing and the preliminary results and status of these test phases. Future anticipated results obtained from unsaturated-zone (UZ) transport testing in the Calico Hills Formation at Busted Butte are also discussed in view of their importance to performance assessment (PA) needs to build confidence in and reduce the uncertainty of site-scale flow-and-transport models and their abstractions for performance for license application. The principal objectives of the test are to address uncertainties associated with flow and transport in the UZ site-process models for Yucca Mountain, as identified by the PA working group in February 1997. These include but are not restricted to: (1) The effect of heterogeneities on flow and transport in unsaturated and partially saturated conditions in the Calico Hills Formation. In particular, the test aims to address issues relevant to fracture-matrix interactions and permeability contrast boundaries; (2) The migration behavior of colloids in fractured and unfractured Calico Hills rocks; (3) The validation through field testing of laboratory sorption experiments in unsaturated Calico Hills rocks; (4) The evaluation of the 3-D site-scale flow-and-transport process model (i.e., equivalent-continuum/dual-permeability/discrete-fracture-fault representations of flow and transport) used in the PA abstractions for license application; and (5) The effect of scaling from lab scale to field scale and site scale.
Date: November 1, 1999
Creator: Bussod, G.Y.; Turin, H.J. & Lowry, W.E.
Partner: UNT Libraries Government Documents Department

Development of the SEAtrace{trademark} barrier verification and validation technology. Final report

Description: In-situ barrier emplacement techniques and materials for the containment of high-risk contaminants in soils are currently being developed by the Department of Energy (DOE). Because of their relatively high cost, the barriers are intended to be used in cases where the risk is too great to remove the contaminants, the contaminants are too difficult to remove with current technologies, or the potential movement of the contaminants to the water table is so high that immediate action needs to be taken to reduce health risks. Assessing the integrity of the barrier once it is emplaced, and during its anticipated life, is a very difficult but necessary requirement. Science and Engineering Associates, Inc., (SEA) and Sandia National Laboratories (SNL) have developed a quantitative subsurface barrier assessment system using gaseous tracers in support of the Subsurface Contaminants Focus Area barrier technology program. Called SEAtrace{trademark}, this system integrates an autonomous, multi-point soil vapor sampling and analysis system with a global optimization modeling methodology to locate and size barrier breaches in real time. The methodology for the global optimization code was completed and a prototype code written using simplifying assumptions. Preliminary modeling work to validate the code assumptions were performed using the T2VOC numerical code. A multi-point field sampling system was built to take soil gas samples and analyze for tracer gas concentration. The tracer concentration histories were used in the global optimization code to locate and size barrier breaches. SEAtrace{trademark} was consistently able to detect and locate leaks, even under very adverse conditions. The system was able to locate the leak to within 0.75 m of the actual value, and was able to determine the size of the leak to within 0.15 m.
Date: August 1, 1998
Creator: Dunn, S.D.; Lowry, W.; Walsh, R.; Rao, D.V. & Williams, C.
Partner: UNT Libraries Government Documents Department