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In situ changes in the moisture content of heated, welded tuff based on thermal neutron measurements

Description: Thermal neutron logs were collected to monitor changes in moisture content within a welded tuff rock mass heated from a borehole containing an electrical heater which remained energized for 195 days. Thermal neutron measurements were made in sampling boreholes before, during and after heating. The results generally corroborated our conceptual understanding of hydrothermal flow as well as most of the numerical modeling conducting for this study. Conceptual models have been developed in conjunction with the numerical model calculations to explain differences in the drying and re-wetting behavior above and below the heater. Numerical modeling indicated that the re-wetting of the dried-out zone was dominated by the binary diffusion of water vapor through fractures. Saturation gradients in the rock matrix resulted in relative humidity gradients which drove water vapor (primarily along fractures) back to the dried-out zone where it condensed along the fracture walls and was imbibed by the matrix. 4 refs., 28 figs.
Date: July 1, 1991
Creator: Ramirez, A.L.; Carlson, R.C. & Buscheck, T.A.
Partner: UNT Libraries Government Documents Department

Horizontal grout barrier project results of the latest testing

Description: Throughout United States Department of Energy (DOE) sites are situations where storage tanks and pits are leaking or have the potential to leak contamination into the soil. Subsequent leaching from rain and groundwater flow disperses the contamination far from the original site and, in some cases, into aquifers which serve as a drinking water source. Fernald Environmental Restoration Management Corporation (FERMCO) at Fernald working with the DOE Office of Technology Development (OTD) and two subcontractors, is pursuing the goal of placing a barrier beneath the contamination to prevent this dispersion. The technology being developed is an in situ approach based on directional drilling and jet grouting techniques developed in the oil fields. The unique barrier techniques being developed depend on innovative tooling and special grouts to install a horizontal barrier underground without disturbing the contaminated soils above. The initial tool designs were tested in December 1992 and were encouraging enough that the DOE agreed to fund continued development. A second set of designs were tested in August 1994. The testing results were less than expected but did provide a number of lessons learned. This paper reports on the third set of tool designs and the results of testing these tools prior to the full demonstration project at Fernald.
Date: March 1, 1995
Creator: Riedel, K.W.; Ridenour, D.E. & Walker, J.
Partner: UNT Libraries Government Documents Department

Preliminary study on improvement of cementitious grout thermal conductivity for geothermal heat pump applications

Description: Preliminary studies were preformed to determine whether thermal conductivity of cementitious grouts used to backfill heat exchanger loops for geothermal heat pumps could be improved, thus improving efficiency. Grouts containing selected additives were compares with conventional bentonite and cement grouts. Significant enhancement of grout alumina grit, steel fibers, and silicon carbide increased the thermal conductivity when compared to unfilled, high solids bentonite grouts and conventional cement grouts. Furthermore, the developed grouts retained high thermal conductivity in the dry state, where as conventional bentonite and cement grouts tend to act as insulators if moisture is lost. The cementitious grouts studied can be mixed and placed using conventional grouting equipment.
Date: June 1, 1996
Creator: Allan, M.L.
Partner: UNT Libraries Government Documents Department

Grout and Glass Performance in Support of Stabilization/Solidification of the MVST Tank Sludges

Description: Wastewater at Oak Ridge National Laboratory (ORNL) is collected, evaporated, and stored in the Melton Valley Storage Tanks (MVST) pending treatment for disposal. The waste separates into two phases: sludge and supematant. Some of the supematant from these tanks has been decanted, solidified into a grout, and stored for disposal as a solid low-level waste. The sludges in the tank bottoms have been accumulating ,for several years. Some of the sludges contain a high amount of gamma activity (e.g., `37CS concentration range of 0.01 3-11 MBq/g) and contain enough transuranic (TRU) radioisotopes to be classified as TRU wastes. Some Resource Conservation and Recovery Act (RCRA) metal concentrations are high enough in the available total constituent analysis for the MVST sludge to be classified as RCRA hazardous; therefore, these sludges are presumed to be mixed TRU waste.
Date: November 1, 1998
Creator: Gilliam, T.M. & Spence, R.D.
Partner: UNT Libraries Government Documents Department

Gas generation from Hanford grout samples

Description: In an extension of our work on the radiolytic processes that occur in the waste tanks at the Hanford site, we studied the gas generation from grout samples that contained nuclear waste simulants. Grout is one option for the long-term storage of low-level nuclear waste solutions but the radiolytic effects on grout have not been thoroughly defined. In particular, the generation of potentially flammable and hazardous gases required quantification. A research team at Argonne examined this issue and found that the total amount of gases generated radiolytically from the WHC samples was an order of magnitude higher than predicted. This implies that novel pathways fro charge migration from the solid grout to the associated water are responsible for gas evolution. The grout samples produced hydrogen, nitrous oxide, and carbon monoxide as well as nitrogen and oxygen. Yields of each of these substances were determined for doses that are equivalent to about 80 years storage of the grout. Carbon monoxide, which was produced in 2% yield, is of particular importance because even small amounts may adversely affect catalytic conversion instrumentation that has been planned for installation in the storage vaults.
Date: March 1, 1996
Creator: Jonah, C.D.; Kapoor, S.; Matheson, M.S.; Mulac, W.A. & Meisel, D.
Partner: UNT Libraries Government Documents Department

Pore solution chemistry of simulated low-level liquid waste incorporated in cement grouts

Description: Expressed pore solutions from simulated low level liquid waste cement grouts cured at room temperature, 50{degree}C and 90{degree}C for various duration were analyzed by standard chemical methods and ion chromatography. The solid portions of the grouts were formulated with portland cement, fly ash, slag, and attapulgite clay in the ratios of 3:3:3:1. Two different solutions simulating off-gas condensates expected from vitrification of Hanford low level tank wastes were made. One is highly alkaline and contains the species Na{sup {plus}}, P0{sub 4}{sup 3-}, N0{sub 2}{sup -}, NO{sub 3}{sup -} and OH{sup -}. The other is carbonated and contains the species, Na{sup {plus}}, PO{sub 4}{sup 3-}, NO{sub 2}{sup -}, NO{sub 3}{sup -}, and CO{sub 3}{sup 2-}. In both cases phosphate rapidly disappeared from the pore solution, leaving behind sodium in the form of hydroxide. The carbonates were also removed from the pore solution to form calcium carbonate and possibly calcium monocarboaluminate. These reactions resulted in the increase of hydroxide ion concentration in the early period. Subsequently there was a significant reduction OH{sup -} and Na{sup {plus}} ion concentrations. In contrast high concentration of N0{sub 2}{sup -} and N0{sub 3}{sup -} were retained in the pore solution indefinitely.
Date: December 1, 1995
Creator: Kruger, A.A.
Partner: UNT Libraries Government Documents Department

Success in horizontal barrier developments

Description: A successful proof of concept demonstration has been conducted of operational methods and tooling for the in situ construction of underground horizontal barriers for the control and containment of groundwater and contamination. The method involves jet grouting with specially adapted tools guided between twin, parallel wells for the placement of a grout beneath a waste site. The objective of the work is to develop reliable methods of constructing extensive, competent horizontal barriers underneath waste sites without excavating or penetrating the waste during the process.
Date: June 1, 1996
Creator: Pettit, P.J.; Ridenour, D.E. & Jalovec, J.
Partner: UNT Libraries Government Documents Department

International technology catalogue: Foreign technologies to support the environmental restoration and waste management needs of the DOE complex

Description: This document represents a summary of 27 foreign-based environmental restoration and waste management technologies that have been screened and technically evaluated for application to the cleanup problems of the Department of Energy (DOE) nuclear weapons complex. The evaluation of these technologies was initiated in 1992 and completed in 1995 under the DOE`s International Technology Coordination Program of the Office of Technology Development. A methodology was developed for conducting a country-by-country survey of several regions of the world where specific environmental technology capabilities and market potential were investigated. The countries that were selected from a rank-ordering process for the survey included: then West Germany, the Netherlands, France, Japan, Taiwan, the Czech and Slovak Republics, and the Former Soviet Union. The notably innovative foreign technologies included in this document were screened initially from a list of several hundred, and then evaluated based on criteria that examined for level of maturity, suitability to the DOE needs, and for potential cost effective application at a DOE site. Each of the selected foreign technologies that were evaluated in this effort for DOE application were subsequently matched with site-specific environmental problem units across the DOE complex using the Technology Needs Assessment CROSSWALK Report. For ease of tracking these technologies to site problem units, and to facilitate their input into the DOE EnviroTRADE Information System, they were categorized into the following three areas: (1) characterization, monitoring and sensors, (2) waste treatment and separations, and (3) waste containment. Technical data profiles regarding these technologies include title and description, performance information, development status, key regulatory considerations, intellectual property rights, institute and contact personnel, and references.
Date: July 1, 1995
Creator: Matalucci, R.V.; Jimenez, R.D. & Esparza-Baca, C.
Partner: UNT Libraries Government Documents Department

Latex-modified grouts for in-situ stabilization of buried transuranic/mixed waste

Description: The Department of Applied Science at Brookhaven national Laboratory was requested to investigate latex-modified grouts for in-situ stabilization of buried TRU/mixed waste for INEL. The waste exists in shallow trenches that were backfilled with soil. The objective was to formulate latex-modified grouts for use with the jet grouting technique to enable in-situ stabilization of buried waste. The stabilized waste was either to be left in place or retrieved for further processing. Grouting prior to retrieval reduces the potential release of contaminants. Rheological properties of latex-modified grouts were investigated and compared with those of conventional neat cement grouts used for jet grouting.
Date: June 1, 1996
Creator: Allan, M.L.
Partner: UNT Libraries Government Documents Department

A field test of permeation grouting in heterogeneous soils using a new generation of barrier liquids

Description: A field demonstration of permeation grouting was conducted at a gravel quarry near Los Banos, California, with the purpose of demonstrating the feasibility of the concept. Two grouts were used: a form of colloidal silica that gels after the addition of a gelling agent, and a polysiloxane that polymerizes after the addition of a catalyst. Both create relatively impermeable barriers in response to the large increase in viscosity during gelation or polymerization, respectively. The grouts were successfully injected at a depth between 10 and 14ft. Subsequent exhumation of the injected gravels revealed that both grouts produced relatively uniform bulbs. Laboratory measurements of the grouted material retrieved from the field showed at least a four order of magnitude reduction in permeability over the ungrouted material.
Date: August 1995
Creator: Moridis, G. J.; Persoff, P.; Apps, J. A.; Myer, L.; Pruess, K. & Yen, P.
Partner: UNT Libraries Government Documents Department


Description: The thermal conductivity of cementitious grouts has been investigated in order to determine suitability of these materials for grouting vertical boreholes used with geothermal heat pumps. The roles of mix variables such as water/cement ratio, sand/cement ratio and superplasticizer dosage were measured. The cement-sand grouts were also tested for rheological characteristics, bleeding, permeability, bond to HDPE pipe, shrinkage, coefficient of thermal expansion, exotherm, durability and environmental impact. This paper summarizes the thermal conductivity, permeability, bonding and exotherm data for selected cementitious grouts. The theoretical reduction in bore length that could be achieved with the BNL-developed cement-sand grouts is examined. Finally, the FY 98 research and field trials are discussed.
Date: April 1, 1998
Creator: ALLAN,M.
Partner: UNT Libraries Government Documents Department

Acid Pit Stabilization Project (Volume 1 - Cold Testing) and (Volume 2 - Hot Testing)

Description: During the summer and fall of Fiscal Year 1997, a Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) Treatability Study was performed at the Idaho National Engineering and Environmental Laboratory. The study involved subsurface stabilization of a mixed waste contaminated soil site called the Acid Pit. This study represents the culmination of a successful technology development effort that spanned Fiscal Years 1994-1996. Research and development of the in situ grout stabilization technique was conducted. Hardware and implementation techniques are currently documented in a patent pending with the United States Patent and Trademark Office. The stabilization technique involved using jet grouting of an innovative grouting material to form a monolith out of the contamination zone. The monolith simultaneously provides a barrier to further contaminant migration and closes voids in the soil structure against further subsidence. This is accomplished by chemical incorporation of contaminants into less soluble species and achieving a general reduction in hydraulic conductivity within the monolith. The grout used for this study was TECT-HG, a relatively dense iron oxide-based cementitious grout. The treatability study involved cold testing followed by in situ stabilization of the Acid Pit. Volume 1 of this report discusses cold testing, performed as part of a ''Management Readiness Assessment'' in preparation for going hot. Volume 2 discusses the results of the hot Acid Pit Stabilization phase of this project. Drilling equipment was specifically rigged to reduce the spread of contamination, and all grouting was performed under a concrete block containing void space to absorb any grout returns. Data evaluation included examination of implementability of the grouting process and an evaluation of the contaminant spread during grouting. Following curing of the stabilized pit, cores were obtained and evaluated for toxicity characteristic leach ing procedure protocol for the main contaminant of concern, which was mercury. In addition, the ...
Date: January 1, 1998
Creator: Loomis, Guy G.; Zdinak, Andrew P.; Ewanic, Mark A. & Jessmore, James J.
Partner: UNT Libraries Government Documents Department

Extrapolation of creep behavior of high-density polyethylene liner in the Catch Basin of grout vaults

Description: Testing was performed to determine if gravel particles will creep into and puncture the high-density polyethylene (HDPE) liner in the catch basin of a grout vault over a nominal 30-year period. Testing was performed to support a design without a protective geotextile cover after the geotextile was removed from the design. Recently, a protective geotextile cover over the liner was put back into the design. The data indicate that the geotextile has an insignificant effect on the creep of gravel into the liner. However, the geotextile may help to protect the liner during construction. Two types of tests were performed to evaluate the potential for creep-related puncture. In the first type of test, a very sensitive instrument measured the rate at which a probe crept into HDPE over a 20-minute period at temperatures of 176{degrees}F to 212{degrees}F (80{degrees}C to 100{degrees}C). The second type of test consisted of placing the liner between gravel and mortar at 194{degrees}F (90{degrees}C) and 45.1 psi overburden pressure for periods up to 1 year. By combining data from the two tests, the long-term behavior of the creep was extrapolated to 30 years of service. After 30 years of service, the liner will be in a nearly steady condition and further creep will be extremely small. The results indicate that the creep of gravel into the liner will not create a puncture during service at 194{degrees}F (90{degrees}C). The estimated creep over 30 years is expected to be less than 25 mils out of the total initial thickness of 60 mils. The test temperature of 194{degrees}F (90{degrees}C) corresponds to the design basis temperature of the vault. Lower temperatures are expected at the liner, which makes the test conservative. Only the potential for failure of the liner resulting from creep of gravel is addressed in this report.
Date: July 1, 1995
Creator: Whyatt, G.A.
Partner: UNT Libraries Government Documents Department

Chemical Grouting Lost-Circulation Zones with Polyurethane Foam

Description: Sandia National Laboratories is developing polyurethane foam as a chemical grout for lost circulation zones. In past work polyurethane foam was tried with limited success in laboratory tests and GDO sponsored field tests. Goals were that the foam expanded significantly and harden to a chillable firmness quickly. Since that earlier work there have been improvements in polyurethane chemistry and the causes of the failures of previous tests have been identified. Recent success in applying pure solution grouts (proper classification of polyurethane--Naudts) in boreholes encourages reevaluating its use to control lost circulation. These successes include conformance control in the oil patch (e.g. Ng) and darn remediation projects (Bruce et al.). In civil engineering, polyurethane is becoming the material of choice for sealing boreholes with large voids and high inflows, conditions associated with the worst lost circulation problems. Demonstration of a delivery mechanism is yet to be done in a geothermal borehole.
Date: July 12, 1999
Creator: Mansure, A.J. & Westmoreland, J.J.
Partner: UNT Libraries Government Documents Department

Hanford tank initiative cone penetrometer stand alone grouting module

Description: The HTI subsurface characterization task will use the Hanford Cone Penetrometer platform (CPP) to deploy contaminant sensor and soil sampling probes into the vadose zone surrounding SST 241-AX-104. Closure of the resulting penetration holes may be stipulated by WAC requirements. A stand alone grouting capability deployable by the CPP has been developed. This qualification test plan defines testing of this capability to be performed at the Immobilized Low Activity Waste Disposal Complex.
Date: October 15, 1998
Creator: CALLAWAY, W.S.
Partner: UNT Libraries Government Documents Department

Hanford waste vitrification systems risk assessment

Description: A systematic Risk Assessment was performed to identify the technical, regulatory, and programmatic uncertainties and to quantify the risks to the Hanford Site double-shell tank waste vitrification program baseline (as defined in December 1990). Mitigating strategies to reduce the overall program risk were proposed. All major program elements were evaluated, including double-shell tank waste characterization, Tank Farms, retrieval, pretreatment, vitrification, and grouting. Computer-based techniques were used to quantify risks to proceeding with construction of the Hanford Waste Vitrification Plant on the present baseline schedule. Risks to the potential vitrification of single-shell tank wastes and cesium and strontium capsules were also assessed. 62 refs., 38 figs., 26 tabs.
Date: September 1, 1991
Creator: Miller, W.C.; Hamilton, D.W.; Holton, L.K. & Bailey, J.W.
Partner: UNT Libraries Government Documents Department

Environmental Protection Department's well inventory (through the second quarter of 1991)

Description: This report is an inventory of the wells contained in Environmental Protection Department/Environmental Monitoring Section (EPD/EMS) documents since the startup of the Savannah River Site (SRS) and includes wells monitored by special request and SRS research wells. Wells listed in this inventory are monitoring wells unless otherwise indicated. The purpose of this report is as follows: To provide a historical record of the wells that EPD/EMS has monitored; to provide a document containing a list of wells that are currently in the EPD/EMS Groundwater Monitoring Program; and to provide pertinent information about all wells listed in EPD/EMS documents.
Date: October 1, 1991
Creator: Rogers, C.D. (Westinghouse Savannah River Co., Aiken, SC (United States))
Partner: UNT Libraries Government Documents Department

Radiolytic and Thermal Generation of Gases from Hanford Grout Samples : Interim Report

Description: Gamma irradiation of WHC-supplied samples of grouted Tank 102-AP simulated nonradioactive waste has been carried out at three dose rates, 0.25, 0.63, and 130 krad/hr. The low dose rate corresponds to that in the actual grout vaults; with the high dose rate, doses equivalent to more than 40 years in the grout vault were achieved. An average G(H2) = 0.047 molecules/100 eV was found, independent of dose rate. The rate of H2 production decreases above 80 Mrad. For other gases, G(N2) = 0.12, G(O2) = 0.026, G(N2O) = 0.011 and G(CO) = 0.0042 at 130 krad/hr were determined. At lower dose rates, N2 and O2 could not be measured because of interference by trapped air. The value of G(H2) is higher than expected, suggesting segregation of water from nitrate and nitrite salts in the grout. The total pressure generated by the radiolysis at 130 krad/h has been independently measured, and total amounts of gases generated were calculated from this measurement. Good agreement between this measurement and the sum of all the gases that were independently determined was obtained. Therefore, the individual gas measurements account for most of the major components that are generated by the radiolysis. At 90 C, H2, N2, and N2O were generated at a rate that could be described by exponential formation of each of the gases. Gases measured at the lower temperatures were probably residual trapped gases. An as yet unknown product interfered with oxygen determinations at temperatures above ambient. The thermal results do not affect the radiolytic findings.
Date: October 1993
Creator: Meisel, Dan; Jonah, Charles D.; Kapoor, S.; Matheson, Max S. & Mulac, W. A.
Partner: UNT Libraries Government Documents Department

Gas Generation from Hanford Grout Samples : Final Report

Description: The radiolytic yields of hydrogen nitrogen, oxygen, nitrous oxide, and carbon monoxide from two batches of WHC-supplied samples of grouted simulated waste have been (gamma) irradiated at several dose rates (0.025, 0.63 and 130 krad/h for hydrogen and 130 krad/h for all other gases). In one batch, the liquid waste simulant that was added to the grout included the original components that were added to Tank 102-AP (labeled "virgin" waste.) The second batch included a similar liquid waste simulant that was preirradiated to 35 Mrad prior to incorporation into the grout. It is believed that the preirradiated samples more closely represent radioactive waste that was stored in the tank for several years. The lowest dose rate corresponds approximately to that expected in the grout; with the high dose rate, doses equivalent to about 85 years storage in grout vaults were achieved. Most of the results on the batch of virgin samples have been reported recently (Report ANL 93/42). Here we report the results from the batch of preirradiated grout samples and compare the results from the two batches. The radiolytic yields of hydrogen and nitrogen are lower in the preirradiated than in the virgin grout. On the other hand G(oxygen) is higher in the preirradiated samples: 0.078 vs. 0.026. The yield of nitrous oxide is essentially the same, G(nitrous oxide) = 0.010, in both. The yields measured from both batches are significantly higher than previously reported values. At 90 C similar amounts of hydrogen were generated thermally from both batches of grout, whereas the total amounts of nitrogen and nitrous oxide were larger for the preirradiated than for the virgin grout samples. At lower temperatures the rate of generation was hardly measurable. Mass spectrometric analysis suggests that NO is thermally (but not radiolytically) released from the grout samples.
Date: March 1994
Creator: Jonah, Charles D.; Kapoor, S.; Matheson, Max S.; Mulac, W. A. & Meisel, Dan
Partner: UNT Libraries Government Documents Department

G-tunnel welded tuff mining experiment preparations

Description: Designers and analysts of radioactive waste repositories must be able to predict the mechanical behavior of the host rock. Sandia National Laboratories elected to conduct a mine-by in welded tuff so that predictive-type information could be obtained regarding the response of the rock to a drill and blast excavation process, where smooth blasting techniques were used. Included in the study were evaluations of and recommendations for various measurement systems that might be used in future mine-by efforts. This report summarizes the preparations leading to the recording of data. 17 refs., 27 figs., 5 tabs.
Date: January 1, 1991
Creator: Zimmerman, R.M.; Bellman, R.A. Jr.; Mann, K.L. & Zerga, D.P.
Partner: UNT Libraries Government Documents Department

Leach test of cladding removal waste grout using Hanford groundwater

Description: This report describes laboratory experiments performed during 1986-1990 designed to produce empirical leach rate data for cladding removal waste (CRW) grout. At the completion of the laboratory work, funding was not available for report completion, and only now during final grout closeout activities is the report published. The leach rates serve as inputs to computer codes used in assessing the potential risk from the migration of waste species from disposed grout. This report discusses chemical analyses conducted on samples of CRW grout, and the results of geochemical computer code calculations that help identify mechanisms involved in the leaching process. The semi-infinite solid diffusion model was selected as the most representative model for describing leaching of grouts. The use of this model with empirically derived leach constants yields conservative predictions of waste release rates, provided no significant changes occur in the grout leach processes over long time periods. The test methods included three types of leach tests--the American Nuclear Society (ANS) 16.1 intermittent solution exchange test, a static leach test, and a once-through flow column test. The synthetic CRW used in the tests was prepared in five batches using simulated liquid waste spiked with several radionuclides: iodine ({sup 125}I), carbon ({sup 14}C), technetium ({sup 99}Tc), cesium ({sup 137}Cs), strontium ({sup 85}Sr), americium ({sup 241}Am), and plutonium ({sup 238}Pu). The grout was formed by mixing the simulated liquid waste with dry blend containing Type I and Type II Portland cement, class F fly ash, Indian Red Pottery clay, and calcium hydroxide. The mixture was allowed to set and cure at room temperature in closed containers for at least 46 days before it was tested.
Date: September 1, 1995
Creator: Serne, R.J.; Martin, W.J. & Legore, V.L.
Partner: UNT Libraries Government Documents Department

Code requirements for concrete repository and processing facilities

Description: The design and construction of facilities and structures for the processing and safe long-term storage of low- and high-level radioactive wastes will likely employ structural concrete. This concrete will be used for many purposes including structural support, shielding, and environmental protection. At the present time, there are no design costs, standards or guidelines for repositories, waste containers, or processing facilities. Recently, the design and construction guidelines contained in American Concrete Institute (ACI), Code Requirements for Nuclear Safety Related Concrete Structures (ACI 349), have been cited for low-level waste (LLW) repositories. Conceptual design of various high-level (HLW) repository surface structures have also cited the ACI 349 Code. However, the present Code was developed for nuclear power generating facilities and its application to radioactive waste repositories was not intended. For low and medium level radioactive wastes, concrete has a greater role and use in processing facilities, engineered barriers, and repository structures. Because of varied uses and performance/safety requirements this review of the current ACI 349 Code document was required to accommodate these special classes of structures.
Date: April 1, 1993
Creator: Hookham, C. J. & Palaniswamy, R.
Partner: UNT Libraries Government Documents Department

FY-95 technology catalog. Technology development for buried waste remediation

Description: The US Department of Energy`s (DOE) Buried Waste Integrated Demonstration (BWID) program, which is now part of the Landfill Stabilization Focus Area (LSFA), supports applied research, development, demonstration, and evaluation of a multitude of advanced technologies dealing with underground radioactive and hazardous waste remediation. These innovative technologies are being developed as part of integrated comprehensive remediation systems for the effective and efficient remediation of buried waste sites throughout the DOE complex. These efforts are identified and coordinated in support of Environmental Restoration (EM-40) and Waste Management (EM-30) needs and objectives. Sponsored by the DOE Office of Technology Development (EM-50), BWID and LSFA work with universities and private industry to develop technologies that are being transferred to the private sector for use nationally and internationally. This report contains the details of the purpose, logic, and methodology used to develop and demonstrate DOE buried waste remediation technologies. It also provides a catalog of technologies and capabilities with development status for potential users. Past FY-92 through FY-94 technology testing, field trials, and demonstrations are summarized. Continuing and new FY-95 technology demonstrations also are described.
Date: October 1, 1995
Partner: UNT Libraries Government Documents Department

Laboratory testing of cement grouting of fractures in welded tuff

Description: Fractures in the rock mass surrounding a repository and its shafts, access drifts, emplacement rooms and holes, and exploratory or in-situ testing holes, may provide preferential flowpaths for the flow of groundwater or air, potentially containing radionuclides. Such cracks may have to be sealed. The likelihood that extensive or at least local grouting will be required as part of repository sealing has been noted in numerous publications addressing high level waste repository closing. The objective of this work is to determine the effectiveness of fracture sealing (grouting) in welded tuff. Experimental work includes measurement of intact and fracture permeability under various normal stresses and injection pressures. Grout is injected into the fractures. The effectiveness of grouting is evaluated in terms of grout penetration and permeability reduction, compared prior to and after grouting. Analysis of the results include the effect of normal stress, injection pressure, fracture roughness, grout rheology, grout bonding, and the radial extent of grout penetration. Laboratory experiments have been performed on seventeen tuff cylinders with three types of fractures: (1) tension induced cracks, (2) natural fractures, and (3) sawcuts. Prior to grouting, the hydraulic conductivity of the intact rock and of the fractures is measured under a range of normal stresses. The surface topography of the fracture is mapped, and the results are used to determine aperture distributions across the fractures. 72 refs., 76 figs., 25 tabs.
Date: March 1, 1991
Creator: Sharpe, C. J. & Daemen, J. J.
Partner: UNT Libraries Government Documents Department