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Disposal of fluidized-bed combustion ash in an underground mine to control acid mine drainage and subsidence

Description: During Phase I (first 18 months) the project is segregated into four areas of reporting: (A) Grout Formulation, (B) Grout Characterization, (C) Water Quality Monitoring, (D) Subsidence Control & Contaminant Transport. The first component involves formulating a grout mixture with appropriate flowability to be used in filling complex mine voids. The Grout Characterization component will determine the flow characteristics of the formulated grout. The Water Quality component involves background monitoring of water quality and precipitation at the Phase III (Longridge) mine site. The last component involves evaluating the strength requirements and the migration of contaminants through the candidate grouts. This report separately discusses progress on all components of the program in order of project subtask.
Date: December 31, 1996
Partner: UNT Libraries Government Documents Department

Characterization of a low-level radioactive waste grout: Sampling and test results

Description: WHC manages and operates the grout treatment facility at Hanford as part of a DOE program to clean up wastes stored at federal nuclear production sites. PNL provides support to the grout disposal program through pilot-scale tests, performance assessments, and formulation verification activities. in 1988 and 1989, over one million gallons of a low-level radioactive liquid waste was processed through the facility to produce a grout waste that was then deposited in an underground vault. The liquid waste was phosphate/sulfate waste (PSW) generated in decontamination of the N Reactor. PNL sampled and tested the grout produced during the second half of the PSW campaign to support quality verification activities prior to grout vault closure. Samples of grout were obtained by inserting nested-tube samplers into the grout slurry in the vault. After the grout had cured, the inner tube of the sampler was removed and the grout samples extracted. Tests for compressive strength, sonic velocity, and leach testing were used to assess grout quality; results were compared to those from pilot-scale test grouts made with a simulated PSW. The grout produced during the second half of the PSW campaign exceeded compressive strength and leachability formulation criteria. The nested tube samplers were effective in collecting samples of grout although their use introduced greater variability into the compressive strength data.
Date: December 1, 1992
Creator: Martin, P.F.C. & Lokken, R.O.
Partner: UNT Libraries Government Documents Department

Review of monitoring wells exhibiting elevated pH in F and H Area

Description: Several of the monitoring wells installed at the Savannah River Plant in the past few years exhibit pH values of 8 or higher. These pHs are significantly higher than average values for the aquifers involved and are also higher than expected for natural waters. They are also inconsistent with observations in nearby wells. It is therefore suspected that the high pHs are not representative of true aquifer conditions. Two previous studies conducted at SRP (Price, 1984; Schreeder, 1986) conclude that high pH readings in M-Area monitoring wells and Z-Area piezometers are the result of contact between groundwater and grout. Price bases his conclusion on water chemistry. Schreeder`s evidence is the relationship between pH and amount of water withdrawn from the piezometers--an initially high pH drops as more water is removed. This conclusion is supported by laboratory measurements on water samples collected from cement-bentonite grout which show pH values of 13. This investigation was undertaken to evaluate contamination by grout and drilling fluid as a possible cause of elevated pH in monitoring wells at SRP and to develop techniques to rehabilitate the affected wells. FSB and HSB wells were used in this study.
Date: July 1988
Creator: Blackmer, G. C.
Partner: UNT Libraries Government Documents Department

Grouting guidelines for Hanford Tanks Initiative cone penetrometer borings

Description: Grouting of an open cone penetrometer (CP) borehole is done to construct a barrier that prevents the vertical migration of fluids and contaminants between geologic units and aquifers intersected by the boring. Whether to grout, the types of grout, and the method of deployment are functions of the site-specific conditions. This report recommends the strategy that should be followed both before and during HTI [Hanford Tanks Initiative] CP deployment to decide specific borehole grouting needs at Hanford SST farms. Topics discussed in this report that bear on this strategy include: Regulatory guidance, hydrogeologic conditions, operational factors, specific CP grouting deployment recommendations.
Date: May 18, 1998
Creator: Iwatate, D.F.
Partner: UNT Libraries Government Documents Department

Lance water injection tests adjacent to the 281-3H retention basin at the Savannah River Site, Aiken, South Carolina

Description: A pilot-scale field demonstration of waste isolation using viscous- liquid containment barriers has been planned for the 281-3H retention basin at the Savannah River Site, Aiken, SC. The 281-3H basin is a shallow retention/seepage basin contaminated mainly by radionuclides. The viscous-liquid containment barrier utilizes the permeation of liquid grout to either entomb the contaminants within a monolithic grout structure or to isolate the waste by drastically reducing the permeability, of the soils around the plume. A clear understanding of the hydrogeologic setting of the retention basin is necessary for proper design of the viscous liquid barrier. To aid in the understanding of the hydrogeology of the 281-3H retention basin, and to obtain critical parameters necessary for grout injection design, a series of tests were undertaken in a region immediately adjacent to the basin. The objectives of the LWIT were: 1. To evaluate the general performance of the Lance Injection Technique for grout emplacement at the site, including the range and upper limits of injection pressures, the flow rates applicable for site conditions, as well as the mechanical forces needed for lance penetration. 2. To obtain detailed information on the injectability of the soils immediately adjacent to the H-area retention basin. 3. To identify any high permeability zones suitable for injection and evaluate their spatial distribution. 4. To perform ground penetrating radar (GPR) to gain information on the structure of the soil column and to compare the results with LWIT data. This report will focus on results pertinent to these objectives.
Date: September 1, 1996
Creator: Freifeld, B.; Myer, L.; Moridis, G.; Cook, P.; James, A.; Pellerin, L. et al.
Partner: UNT Libraries Government Documents Department

Performance assessment of grouted double-shell tank waste disposal at Hanford. Revision 1

Description: This document assesses the performance of the Grout Disposal Facility after closure. The facility and disposal environment are modeled to predict the long-term impacts of the disposal action. The document concludes that the disposal system provides reasonable assurance that doses to the public will remain within the performance objectives. This document is required for DOC Order 5820.2A.
Date: September 1, 1994
Creator: Shade, J.W., Kincaid, C.T.; Whyatt, G.A.; Rhoads, K.; Westsik, J.H. Jr.; Freshley, M.D.; Blanchard, K.A. et al.
Partner: UNT Libraries Government Documents Department

Field grouting summary report on the WAG 4 seeps 4 and 6 removal action project, Oak Ridge National Laboratory, Oak Ridge, Tennessee. Volume 3. Appendixes E and F

Description: During the summer of 1996, a unique multi-phase, multi-stage, low-pressure permeation grouting pilot program was performed inside portions of four unlined waste disposal trenches at Waste Area Grouping (WAG) 4 at Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee. The project was deemed a non-time-critical removal action under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA); however, due to a history of heavy precipitation in the fall, the schedule was fast-tracked to meet an October 31, 1996 grouting completion date. The technical objective of the removal action was to reduce the off-site transport of j Strontium 90 ({sup 90}Sr) by grouting portions of four waste disposal trenches believed to be responsible for over 70 percent of the {sup 90}Sr leaving the site. A goal of the grouting operation was to reduce the average in situ hydraulic conductivity of the grouted waste materials to a value equal to or less than 1 x 10{sup -6} cm/sec. This target hydraulic conductivity value was established to be at least two orders of magnitude lower than that of the surrounding natural ground.
Date: May 1997
Partner: UNT Libraries Government Documents Department

Thermally conductive cementitious grouts for geothermal heat pumps. Progress report FY 1998

Description: Research commenced in FY 97 to determine the suitability of superplasticized cement-sand grouts for backfilling vertical boreholes used with geothermal heat pump (GHP) systems. The overall objectives were to develop, evaluate and demonstrate cementitious grouts that could reduce the required bore length and improve the performance of GHPs. This report summarizes the accomplishments in FY 98. The developed thermally conductive grout consists of cement, water, a particular grade of silica sand, superplasticizer and a small amount of bentonite. While the primary function of the grout is to facilitate heat transfer between the U-loop and surrounding formation, it is also essential that the grout act as an effective borehole sealant. Two types of permeability (hydraulic conductivity) tests was conducted to evaluate the sealing performance of the cement-sand grout. Additional properties of the proposed grout that were investigated include bleeding, shrinkage, bond strength, freeze-thaw durability, compressive, flexural and tensile strengths, elastic modulus, Poisson`s ratio and ultrasonic pulse velocity.
Date: November 1, 1998
Creator: Allan, M.L. & Philippacopoulos, A.J.
Partner: UNT Libraries Government Documents Department

Demonstration of In-Situ Stabilization of Buried Waste at Pit G-11 at the Brookhaven National laboratory Glass Pits Disposal Site

Description: In 1989 BNL was added to the EPAs National Priorities List. The site is divided into seven operable units (OU). OU-I includes the former landfill area. The field task site is noted as the AOC 2C Glass Holes location. Beginning in the 1960s and continuing into the 1980s, BNL disposed of laboratory waste (glassware, chemicals and animal carcasses) in numerous shallow pits. The drivers for remediating the pits are; historical records that indicate hazardous materials may have been disposed of in the pits; ground water contamination down gradient of the pits; a test excavation of one of the glass holes that unearthed laboratory glass bottles with unidentified liquids still contained; and the fact that BNL rests atop an EPA designated sole-source aquifer. The specific site chosen for this demonstration was pit G-11. The requirements that lead to choosing this pit were; a well characterized pit and a relatively isolated pit where our construction operations would not impact on adjacent pits. The glass holes area, including pit G-11, was comprehensively surveyed using a suite of geophysical techniques (e.g., EM-31, EM-61, GPR). Prior to stabilizing the waste form a subsurface barrier was constructed to contain the entire waste pit. The pit contents were then stabilized using a cement grout applied via jet grouting. The stabilization was performed to make removal of the waste from the pit easier and safer in terms of worker exposure. The grouting process would mix and masticate the waste and grout and form a single monolithic waste form. This large monolith would then be subdivided into smaller 4 foot by 4 foot by 10-12 foot block using a demolition grout. The smaller blocks would then be easily removed from the site and disposed of in a CERCLA waste site.
Date: January 1, 1999
Creator: Dwyer, B.P.; Gilbert, J. & Heiser, J.
Partner: UNT Libraries Government Documents Department

Characterization Plan for the Old Hydrofracture Facility

Description: US Department of Energy (DOE) facilities are required to comply fully with all federal and state regulations. In response to this requirement, the Oak Ridge National Laboratory (ORNL) has established the remedial action program, to provide comprehensive management of areas where past research, development, and waste management activities have been conducted and have resulted in residual contamination of facilities or the environment. One of the objectives of this program is to define the extent of contamination at these sites. The intent is to document the known environmental characteristics of the sites and identify the additional actions, such as sampling, analytical measurements, and modeling, necessary to confirm contamination and the possible migration of contaminants from the sites. One of these sites is the Old Hydrofracture Facility (OHF). The OHF was used for the permanent disposal of liquid radioactive waste in impermeable shale formations at depths ranging from about 230 to 300 m (750 to 1000 ft), from 1964 to 1979. The liquid waste was blended into a pumpable grout by mixing it with cement and special clays used to immobilize radionuclides against groundwater transport. This report summarizes the results of several studies at ORNL that have measured the concentration of radionuclides and, to some extent, concentrations of hazardous chemicals in the sediment of the impoundment, as well as the concentrations in soils and groundwater near the facility. The report addresses only the contamination of and the potential releases to the environment that might result from the facility per se and makes not attempt to address potential releases that might result from permanent disposal of wastes (i.e., the grout sheets) during its operation. Outlined in the report are the additional actions needed to obtain the information required to confirm the extent of contamination within the facility. The major efforts include the measurement ...
Date: January 1, 1999
Creator: Francis, C.W.
Partner: UNT Libraries Government Documents Department

Biodenitrification in Sequencing Batch Reactors. Final report

Description: One plan for stabilization of the Solar Pond waters and sludges at Rocky Flats Plant (RFP), is evaporation and cement solidification of the salts to stabilize heavy metals and radionuclides for land disposal as low-level mixed waste. It has been reported that nitrate (NO{sub 3}{sub {minus}}) salts may interfere with cement stabilization of heavy metals and radionuclides. Therefore, biological nitrate removal (denitrification) may be an important pretreatment for the Solar Pond wastewaters at RFP, improving the stability of the cement final waste form, reducing the requirement for cement (or pozzolan) additives and reducing the volume of cemented low-level mixed waste requiring ultimate disposal. A laboratory investigation of the performance of the Sequencing Batch Reactor (SBR) activated sludge process developed for nitrate removal from a synthetic brine typical of the high-nitrate and high-salinity wastewaters in the Solar Ponds at Rocky Flats Plant was carried out at the Environmental Engineering labs at the University of Colorado, Boulder, between May 1, 1994 and October 1, 1995.
Date: January 23, 1996
Creator: Silverstein, J.
Partner: UNT Libraries Government Documents Department

HWMA closure plan for the Waste Calcining Facility at the Idaho National Engineering Laboratory

Description: The Waste Calcining Facility (WCF) calcined and evaporated aqueous wastes generated from the reprocessing of spent nuclear fuel. The calciner operated from 1963 to 1981, primarily processing high level waste from the first cycle of spent fuel extraction. Following the calciner shutdown the evaporator system concentrated high activity aqueous waste from 1983 until 1987. In 1988, US Department of Energy Idaho Operations Office (DOE-ID) requested interim status for the evaporator system, in anticipation of future use of the evaporator system. The evaporator system has not been operated since it received interim status. At the present time, DOE-ID is completing construction on a new evaporator at the New Waste Calcining Facility (NWCF) and the evaporator at the WCF is not needed. The decision to not use the WCF evaporator requires Lockheed Idaho Technologies Company (LITCO) and DOE-ID to close these units. After a detailed evaluation of closure options, LITCO and DOE-ID have determined the safest option is to fill the voids (grout the vessels, cells and waste pile) and close the WCF to meet the requirements applicable to landfills. The WCF will be covered with a concrete cap that will meet the closure standards. In addition, it was decided to apply these closure standards to the calcining system since it is contained within the WCF building. The paper describes the site, waste inventory, closure activities, and post-closure care plans.
Date: May 1, 1996
Partner: UNT Libraries Government Documents Department

Physical barriers formed from gelling liquids: 1. numerical design of laboratory and field experiments

Description: The emplacement of liquids under controlled viscosity conditions is investigated by means of numerical simulations. Design calculations are performed for a laboratory experiment on a decimeter scale, and a field experiment on a meter scale. The purpose of the laboratory experiment is to study the behavior of multiple gout plumes when injected in a porous medium. The calculations for the field trial aim at designing a grout injection test from a vertical well in order to create a grout plume of a significant extent in the subsurface.
Date: January 1, 1994
Creator: Finsterle, S.; Moridis, G.J.; Pruess, K. & Persoff, P.
Partner: UNT Libraries Government Documents Department

Durability of double-shell tank waste grouts

Description: This report summarizes results of studies conducted in FY89 to assess the durability of grouted DST waste. This is in support of WHC`s grout disposal program to determine the physical/chemical properties of simulated DST grouts cured for extended time periods at elevated temperatures. This report presents results of tests on simulated DST grout samples cured up to 6 months at 75 to 95 C. All the testing and characterization were done on a single formulation of DS slurry feed grout. The simulated waste was the same as in the Nov. 1988 pilot- scale test of grout processing. The dry blend (47 wt% slag, 47 wt% class F fly ash, 6 wt% type I/II portland cement) was mixed with the simulated waste at a mix ratio of 9 lb/gal. Resultant grout slurry was cast into molds and cured at 100% RH at 75, 85, and 95 C. Leach resistance and compressive strength decreased with curing times and temperatures. The samples absorbed water during curing (up to 9 wt%) as a result of osmotic pressures caused by the high salt content within the grout, and this may have caused microcracking and reduced strength. Cracking due to increased internal pressures from salt crystallization also may have occurred as the samples cooled from curing.
Date: December 1, 1992
Creator: Lokken, R.O.; Martin, P.F.C. & Shade, J.W.
Partner: UNT Libraries Government Documents Department

Removal action report on Waste Area Grouping 4 seeps 4 and 6 at Oak Ridge National Laboratory, Oak Ridge, Tennessee

Description: This report documents removal action activities for a Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) non-time-critical removal action as described in the Action Memorandum prepared in 1996. The technical objective of this removal action was to reduce the release of strontium 90 ({sup 90}Sr) into an ephemeral tributary to White Oak Creek from Waste Area Grouping 4 (WAG 4) seeps, as measured at Monitoring Station (MS) 1 at ORNL, Oak Ridge, TN. Design was initiated in early January 1996 and grouting activities were completed in late October 9996. Portions of four waste disposal trenches were injected using low-temperature permeation grouting technology with multiple formulations of grouts to reduce the in situ hydraulic conductivity of the waste materials and ultimately reduce the off-site transport of {sup 90}Sr.
Date: December 1, 1996
Partner: UNT Libraries Government Documents Department

Direct Grout Stabilization of High Cesium Salt Waste: Salt Alternative Phase III Feasibility Study

Description: The direct grout alternative is a viable option for treatment/stabilization and disposal of salt waste containing Cs-137 concentrations of 1-3 Ci/gal. The composition of the direct grout salt solution is higher in sodium salts and contains up to a few hundred ppm Cs-137 more than the current reference salt solution. However it is still similar to the composition of the current reference salt solution. Consequently, the processing, setting, and leaching properties (including TCLP for Cr and Hg) of the direct grout and current saltstone waste forms are very similar. The significant difference between these waste solutions is that the high cesium salt solution will contain between 1 and 3 Curies of Cs-137 per gallon compared to a negligible amount in the current salt solution. This difference will require special engineering and shielding for a direct grout processing facility and disposal units to achieve acceptable radiation exposure conditions. The Cs-137 concentration in the direct grout salt solution will also affect the long-term curing temperature of the waste form since 4.84 Watts of energy are generated per 1000 Ci of Cs-137. The temperature rise of the direct grout during long-term curing has been calculated by A. Shaddy, SRTC.1 The effect of curing temperature on the strength, leaching and physical durability of the direct grout saltstone is described in this report. At the present time, long term curing at 90 degrees C appears to be unacceptable because of cracking which will affect the structural integrity as evaluated in the immersion test. (The experiments conducted in this feasibility study do not address the effect of cracking on leaching of contaminants other than Cr, Hg, and Cs.) No cracking of the direct grout or reference saltstone waste forms was observed for samples cured at 70 degrees C. At the present time the implications of waste ...
Date: December 7, 1998
Creator: Langton, C.A.
Partner: UNT Libraries Government Documents Department

Pressure grouting of fractured basalt flows

Description: This report describes a field trial of pressure grouting in basalt and the results of subsequent coring and permeability measurement activities. The objective was to show that the hydraulic conductivity of fractured basalt bedrock can be significantly reduced by pressure injection of cementitious materials. The effectiveness of the pressure grout procedure was evaluated by measuring the change in the hydraulic conductivity of the bedrock. The extent of grout penetration was established by analyzing postgrout injection drilling chips for the presence of a tracer in the grout and also by examining cores of the treated basalt. Downhole radar mapping was used to establish major lava flow patterns and follow water movement during a surface infiltration test. A site called Box Canyon, which is located northwest of the INEL, was chosen for this study due to the similarity of this surface outcrop geology to that of the underlying bedrock fracture system found at the Radioactive Waste Management Complex. This study showed that hydraulic conductivity of basalt can be reduced through pressure grouting of cementitious material.
Date: April 1, 1996
Creator: Shaw, P.; Weidner, J.; Phillips, S. & Alexander, J.
Partner: UNT Libraries Government Documents Department

A design study for a medium-scale field demonstration of the viscous barrier technology

Description: This report is the design study for a medium-scale field demonstration of Lawrence Berkeley National Laboratory`s new subsurface containment technology for waste isolation using a new generation of barrier liquids. The test site is located in central California in a quarry owned by the Los Banos Gravel Company in Los Banos, California, in heterogeneous unsaturated deposits of sand, silt, and -ravel typical of many of the and DOE cleanup sites and particularly analogous to the Hanford site. The coals of the field demonstration are (a) to demonstrate the ability to create a continuous subsurface barrier isolating a medium-scale volume (30 ft long by 30 ft wide by 20 ft deep, i.e. 1/10th to 1/8th the size of a buried tank at the Hanford Reservation) in the subsurface, and (b) to demonstrate the continuity, performance, and integrity of the barrier.
Date: September 1, 1996
Creator: Moridis, G.; Yen, P.; Persoff, P.; Finsterle, S.; Williams, P.; Myer, L. et al.
Partner: UNT Libraries Government Documents Department

Stabilization of in-tank residuals and external-tank soil contamination: FY 1997 interim report

Description: This interim report evaluates various ways to stabilize decommissioned waste tanks and contaminated soils at the AX Tank Farm as part of a preliminary evaluation of end-state options for the Hanford tanks. Five technical areas were considered: (1) emplacement of smart grouts and/or other materials, (2) injection of chemical-getters into contaminated soils surrounding tanks (soil mixing), (3) emplacement of grout barriers under and around the tanks, (4) the use of engineered barriers over the tanks, and (5) the explicit recognition that natural attenuation processes do occur. Research topics are identified in support of key areas of technical uncertainty, in each of the five technical areas. Detailed cost/benefit analyses of the recommended technologies are not provided in this evaluation, performed by Sandia National Laboratories, Albuquerque, New Mexico.
Date: October 9, 1997
Creator: Becker, D.L.
Partner: UNT Libraries Government Documents Department

Grout and glass performance in support of stabilization/solidification of ORNL tank sludges

Description: Wastewater at Oak Ridge National Laboratory (ORNL) is collected, evaporated, and stored in the Melton Valley Storage Tanks (MVST) and Bethel Valley Evaporator Storage Tanks (BVEST) pending treatment for disposal. In addition, some sludges and supernatants also requiring treatment remain in two inactive tank systems: the gunite and associated tanks (GAAT) and the old hydrofracture (OHF) tank. The waste consists of two phases: sludge and supernatant. The sludges contain a high amount of radioactivity, and some are classified as TRU sludges. Some Resource Conservation and Recovery Act (RCRA) metal concentrations are high enough to be defined as RCRA hazardous; therefore, these sludges are presumed to be mixed TRU waste. Grouting and vitrification are currently two likely stabilization/solidification alternatives for mixed wastes. Grouting has been used to stabilize/solidify hazardous and low-level radioactive waste for decades. Vitrification has been developed as a high-level radioactive alternative for decades and has been under development recently as an alternative disposal technology for mixed waste. The objective of this project is to define an envelope, or operating window, for grout and glass formulations for ORNL tank sludges. Formulations will be defined for the average composition of each of the major tank farms (BVEST/MVST, GAAT, and OHF) and for an overall average composition of all tank farms. This objective is to be accomplished using surrogates of the tank sludges with hot testing of actual tank sludges to check the efficacy of the surrogates.
Date: September 1, 1998
Creator: Spence, R.D.; Mattus, C.H. & Mattus, A.J.
Partner: UNT Libraries Government Documents Department

Disposal of fluidized-bed combustion ash in an underground mine to control acid mine drainage and subsidence. Quarterly technical progress report, December 1994--February 1995

Description: Research continued on the disposal of fluidized-bed combustion products in underground mines in order to control acid mine drainage and ground subsidence. This quarter, the installation of a coal ash grout into an underground mine void was accomplished. A mixture of 10% portland cement was added to the ash. Problems arose with the clumping of the grout.
Date: March 1, 1995
Partner: UNT Libraries Government Documents Department

Formulation verification study results for Tank 106-AN waste

Description: Because of the excessive heat generated during hydration of double- shell tank waste grouts using 47 wt% blast furnace slag/47 wt% class F fly ash/6 wt% type I/II Portland cement, a modified formulation was recommended for testing of Tank 106-AN grout. The recommended dry blend is: 40 wt% agricultural grade CaCO{sub 3} (ground limestone), 28 wt% blast furnace slag, 28 wt% class F fly ash, and 4 wt% type I/II cement. Verification studies with this dry blend showed that the only criterion not met in all cases was for drainable liquid.
Date: December 1, 1992
Creator: Lokken, R.O.
Partner: UNT Libraries Government Documents Department

Durability of double-shell slurry feed grouts: FY-90 results

Description: Plans for disposal of the low-level fraction of selected double-shell tank wastes at Hanford include grouting. Grout disposal is the process of mixing low-level liquid waste with cementitious powders and pumping the slurry to near-surface, underground concrete vaults; hydration results in the formation of a solid product that binds/encapsulates the radioactive/hazardous constituents. In this durability program, previous studies have indicated a strong impact from curing temperature/time on strength and leach resistance of DSSF grouts. The current studies were expanded to determine whether these impacts could be attributed to other factors, such as dry blend composition and waste concentration. Major conclusions: grouts from dry blends with 40 wt% limestone had lower strengths; compressive strengths and leach resistance decreased with increased curing temperature/time; leach resistance increased for grouts prepared with dilute DSSF; nitrate leach resistance increased with high slag/cement ratios, dilute DSSF, and low curing temperatures; amount of drainable liquids for grouts using diluted DSSF was lowest when slag content was high; the 2 most significant factors affecting grout properties were the slag/cement ratio and waste dilution (slag-waste reactions appear to dominate the properties of DSSF grouts).
Date: December 1, 1992
Creator: Lokken, R.O. & Martin, P.F.C.
Partner: UNT Libraries Government Documents Department

Heat of hydration of double-shell slurry feed grouts

Description: Samples of double-shell slurry feed (DSSF) grout (used in solidifying the waste stored in DS tanks at Hanford) were prepared and tested in adiabatic calorimeters to determine the effect of waste concentration and dry blend variations on the heat of hydration. Changes in DSSF waste concentration had the greatest impact on the overall heat of hydration of the grouts. Grouts prepared with dilute (100 times) DSSF had temperature rises up to 37 C less than with grouts prepared that for undiluted DSSF (15 C vs 52 C). All the grouts prepared with undiluted DSSF had temperature rises that exceeded 45 C. Partial neutralization of the DSSF with acids resulted in delayed reactions and lower temperature rises than that occurring in the reference grout. The temperature rise of a DSSF grout prepared with waste partially neutralized with HCl was 28 C after 300 hr hydration. Temperature rise for a grout made with DSSF partially neutralized with H3PO4 was 43 C. These values compare with a temperature rise of >52 C for a grout made with untreated DSSF. Decreasing the mix ratio from 9 lb/gal to 7.5 lb/gal did not significantly reduce the adiabatic temperature rise of grouts prepared with partially neutralized DSSF waste.
Date: December 1, 1992
Creator: Lokken, R.O.
Partner: UNT Libraries Government Documents Department