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Integration of advanced geoscience and engineering techniques to quantify interwell heterogeneity. Quarterly report, 1 October 1995--31 December 1995

Description: The objective of this project is to integrate advanced geoscience and reservoir engineering concepts with the goal of quantifying the dynamics of fluid-rock and fluid-fluid interactions as they relate to reservoir architecture and lithologic characterization. This interdisciplinary effort will integrate geological and geophysical data with engineering and petrophysical results through reservoir simulation. Technical progress is reported for: Geologic studies, single well wettability tracer test for Sulimar Queen Field; field operations; and reservoir modeling.
Date: December 31, 1995
Creator: Buckley, J.S.; Weiss, W.W. & Ouenes, A.
Partner: UNT Libraries Government Documents Department

Mathematical and geological approaches to minimizing the data requirements for statistical analysis of hydraulic conductivity distribution. Annual report

Description: The following research was completed: refinement of air-pereameter design, calibration; collection of air-flow-rate data at the facies scale; mapping of depositional facies at an outcrop west of Belen, New Mexico; delineation of permeability facies from mapped depositional facies and geostatitistical analysis of air-flow-rate data observed at the facies scale (Sierra Ladrones formation); and evaluation of threshold-crossing theory.
Date: August 1, 1990
Creator: Phillips, F.M. & Wilson, J.L.
Partner: UNT Libraries Government Documents Department

Improved efficiency of miscible CO{sub 2} floods and enhanced prospects for CO{sub 2} flooding heterogeneous reservoirs. Quarterly technical progress report, April 1, 1996--June 30, 1996

Description: Progress has been made in each of the three project areas during this quarter. Each quarter we are highlighting one project area. This quarter, Task 2 is highlighted with expanded details. Significant progress has been made this quarter in testing the functionalities of the foam-durability apparatus for assessment of foam properties at reservoir conditions. Another surfactant, Alipal{reg_sign} CD-128 at a concentration of 1000 ppm, was used for core flooding experiments. The foam mobility data showed a significant reduction of CO{sub 2} mobility and a favorable mobility dependence on rock permeability. Two slim tube test series and continuous phase equilibrium were done to examine the effects of pressure, temperature, and oil composition on oil displacement efficiency. A new series of core foam tests were completed to study the effects of flow rate, CO{sub 2} fraction (foam) quality, and rock permeability on foam-flow behavior. We are in the process of moving the foam reservoir simulator MASTER from a workstation to a Pentium PC environment and test MASTER on a 166 MHz Pentium PC. IFT of CO{sub 2}/crude oil has been measured using our pendant drop measurement system at 138{degrees}F and pressures from 850 psig to 2200 psig. The CO{sub 2} gravity drainage experiment that is in progress using a 50md Berea core at 138{degrees}F and pressures from 1700 to 2000 psig has reached 48% oil recovery and is continuing to increase. The mathematical model developed previously matches the experimental response accurately.
Date: July 20, 1996
Creator: Schechter, D.S.
Partner: UNT Libraries Government Documents Department

Improved methods for water shutoff. Semi-annual report, May 1, 1996--September 30, 1996

Description: In the United States, more than 20 billion barrels of water are produced each year during oilfield operations. Today, the cost of water disposal is typically between $0.25 and $0.50 per bbl for pipeline transport and $1.50 per bbl for trucked water. Therefore, there is a tremendous economic incentive to reduce water production if that can be accomplished without significantly sacrificing hydrocarbon production. For each 1% reduction in water production, the cost-savings to the oil industry could be between $50,000,000 and $100,000,000 per year. Reduced water production would result directly in improved oil recovery (IOR) efficiency in addition to reduced oil-production costs. A substantial positive environmental impact could also be realized if significant reductions are achieved in the amount of water produced during oilfield operations. In an earlier project, we identified fractures (either naturally or artificially induced) as a major factor that causes excess water production and reduced oil recovery efficiency, especially during waterfloods and IOR projects. We also found fractures to be a channeling and water-production problem that has a high potential for successful treatment by gels and certain other chemical blocking agents. By analogy, these blocking materials also have a high potential for treating narrow channels behind pipe and small casing leaks. We also determined that the ability of blocking agents to reduce permeability to water much more than that to oil is critical to the success of these blocking treatments in production wells if zones are not isolated during placement of the blocking agents.
Date: August 1, 1997
Creator: Seright, R.S.
Partner: UNT Libraries Government Documents Department

Preoperational radiation surveillance of the WIPP Project by EEG for the years 1993 - 1995

Description: Average {sup 241}Am, {sup 239+240}Pu and {sup 238}Pu concentrations measured in ambient air near the Waste Isolation Pilot Plant (WIPP) site during 1993, 1994 and 1995 are consistent with similar data reported by the U.S. Environmental Protection Agency (EPA) and Los Alamos National Laboratory (LANL) for Espanola, Pojoaque and Santa Fe, New Mexico. Through the use of replicate analyses of matrix blanks minimum detectable activity (MDA), minimum detectable concentration (MDC) and action levels (ACTL) were established for the Environmental Evaluation Group (EEG) measurement system. Using MDA data from fixed air sampler (FAS) filters and conservative assumptions applied in the National Council on Radiation Protection and Measurements (NCRP) Report 123 (NCRP 1996), it is shown that the EEG sampling and measurement methodology is capable of detecting effluent air emissions which would produce a dose that is approximately 1000 times below the 40 CFR 191 Subpart A limit of 2.5E{sup -4} Sv/y (25 mrem/y). A similar calculation using the NCRP worksheet with storm water effluent MDCs found the EEG measurement program capable of detecting actinide emissions which would result in a dose that is approximately 10 times below the dose limits in 40 CFR 191 Subpart A and 40 CFR 61 Subpart H.
Date: March 1, 1998
Creator: Kenney, J.W.; Gray, D.H. & Ballard, S.C.
Partner: UNT Libraries Government Documents Department

A geological approach to characterizing aquifer heterogeneity. Completion report, 1990--1994

Description: Spatial variations of hydraulic conductivity have generally been recognized as the dominant medium-independent control on the transport and dispersion of contaminants in groundwater. Mathematical models that use statistical descriptions of the hydraulic conductivity spatial distribution are available to predict contaminant transport. Such models are expected to be major tools in dealing with contamination problems at DOE sites. Unfortunately, the statistical parameters needed for such models can usually only be obtained through geostatistical analysis of very large numbers of hydraulic conductivity measurements, with associated large costs and often-significant human risk at highly contaminated sites. More accurate and realistic conceptual models for the actual distribution of hydraulic conductivity, requiring fewer field data, would increase the reliability of contaminant transport predictions while decreasing their cost. The objectives of the project can therefore be summarized in the following question: How can the data requirements for geostatistical analysis of hydraulic parameters be reduced by incorporation of geological expertise and macroscopic proxy information into new mathematical models. Specifically, the authors proposed to combine intensive geological field observations with permeability measurements to discover relationships between sediment depositional processes, geological structures, and the geostatistics of the permeability distributions that result.
Date: July 31, 1998
Creator: Phillips, F.; Wilson, J. & Gutjahr, A.
Partner: UNT Libraries Government Documents Department

A study of the relationship between permeability distributions and small scale sedimentary features in a fluvial formation

Description: This study focuses on styles of small-scale heterogeneity found in fluvial sand and soil bodies. Over 1,700 in situ measurements of air permeability were taken in an outcrop-based study which joins observations of sedimentary features with their associated permeability distributions. The relationship between sedimentology and hydrologic parameters provides a geologic framework to assess geostatistical hypotheses. The soils in the study area are found to have a significantly lower permeability than the channel sand deposits. The soil deposits showed a significant lack of observable small scale sedimentary structures, which is reflected in the experimental variograms. The permeability distribution in these study sites appears to be adequately represented by a continuous gaussian random field model. The presence of calcium carbonate nodules in the soils is related to the permeability distribution. Correlation lengths in the channel sands perpendicular to stratigraphy are significantly shorter than those observed parallel to stratigraphy. A sedimentological, bounding surfaces model is evaluated with regard to permeability distributions. In deposits of little sedimentary structure, the mean and variance may adequately characterize the permeability distribution. Where significant sedimentary structure exists, the bounding surfaces model can be used to determine the scales of variability present in the permeability distribution and may also be used to infer an appropriate choice of random field model.
Date: October 1, 1993
Creator: Gotkowitz, M.
Partner: UNT Libraries Government Documents Department

PREP program final report

Description: The overall goal of the project partially funded by DOE was to encourage a greater number of the targeted high school students to acquire the necessary skills to succeed in rigorous college academic programs and to enter science-based disciplines. These goals were met and the program was judged to be a success. Students participating in the program were involved in a rigorous daily academic program of formal instruction. Participants lived in the residence halls and participated in many aspects of college life, including planned recreational activities. Students were also involved in academic year activities to maintain a heightened awareness and interest in science-based fields. The program sought to provide students with the following hands on laboratory and field site learning experiences as well as minority role models--scientists and engineers, resident advisors, and tutors. Curricular focal points were environmental science, supported by courses and labs in mathematics, technical writing, and chemistry. The 1994 summer program was the second year of the environmental science focus. Students chose topics relevant to New Mexico such as Coal Mining, Landfills, and Tribal Water Rights. The program was judged to have succeeded in the overall goal of encouraging targeted precollege students to acquire the necessary skills to succeed in rigorous college academic programs and to enter science-based disciplines.
Date: November 1, 1998
Partner: UNT Libraries Government Documents Department

Small scale laboratory studies of flow and transport phenomena in pores and fractures: Phase 2. Technical completion report

Description: Pore level laboratory experiments using microscopy permit the in situ visualization of flow and transport phenomena, that can be recorded on film or videotape. One of the principal tools for visualization is the etched glass micromodel, which is composed of a transparent two dimensional network of three dimensional pores. The spatial scale of interest in these models extends from the individual pore, up to a network of pores, perhaps with small scale heterogeneities. Micromodels are best used to help validate concepts and assumptions, and to elucidate new, previously unrecognized phenomena for further study. They are not quantitative tools, but should be used in combination with quantitative tools such as column studies or mathematical models. There are three applications: multi-phase flow, colloid transport, and bacterial transport and colonization. Specifically the authors have examined behavior of relevance to liquid-liquid mass transfer (solubilization of capillary trapped organic liquids); liquid-gas mass transfer (in situ volatilization); mathematical models of multi-phase pressure-saturation relationships; colloid movement, attachment and detachment in the presence of fluid-fluid interfaces, clay interference with multi-phase flow; and heterogeneity effects on multi-phase flow and colloid movement.
Date: January 1, 1997
Creator: Wilson, J.L.
Partner: UNT Libraries Government Documents Department

A conceptual sedimentological-geostatistical model of aquifer heterogeneity based on outcrop studies

Description: Three outcrop studies were conducted in deposits of different depositional environments. At each site, permeability measurements were obtained with an air-minipermeameter developed as part of this study. In addition, the geological units were mapped with either surveying, photographs, or both. Geostatistical analysis of the permeability data was performed to estimate the characteristics of the probability distribution function and the spatial correlation structure. The information obtained from the geological mapping was then compared with the results of the geostatistical analysis for any relationships that may exist. The main field site was located in the Albuquerque Basin of central New Mexico at an outcrop of the Pliocene-Pleistocene Sierra Ladrones Formation. The second study was conducted on the walls of waste pits in alluvial fan deposits at the Nevada Test Site. The third study was conducted on an outcrop of an eolian deposit (miocene) south of Socorro, New Mexico. The results of the three studies were then used to construct a conceptual model relating depositional environment to geostatistical models of heterogeneity. The model presented is largely qualitative but provides a basis for further hypothesis formulation and testing.
Date: January 1, 1994
Creator: Davis, J.M.
Partner: UNT Libraries Government Documents Department

Integration of advanced geoscience and engineering techniques to quantify interwell heterogeneity in reservoir models. Final report, September 29, 1993--September 30, 1996

Description: The goal of this three-year project was to provide a quantitative definition of reservoir heterogeneity. This objective was accomplished through the integration of geologic, geophysical, and engineering databases into a multi-disciplinary understanding of reservoir architecture and associated fluid-rock and fluid-fluid interactions. This interdisciplinary effort integrated geological and geophysical data with engineering and petrophysical results through reservoir simulation to quantify reservoir architecture and the dynamics of fluid-rock and fluid-fluid interactions. An improved reservoir description allows greater accuracy and confidence during simulation and modeling as steps toward gaining greater recovery efficiency from existing reservoirs. A field laboratory, the Sulimar Queen Unit, was available for the field research. Several members of the PRRC staff participated in the development of improved reservoir description by integration of the field and laboratory data as well as in the development of quantitative reservoir models to aid performance predictions. Subcontractors from Stanford University and the University of Texas at Austin (UT) collaborated in the research and participated in the design and interpretation of field tests. The three-year project was initiated in September 1993 and led to the development and application of various reservoir description methodologies. A new approach for visualizing production data graphically was developed and implemented on the Internet. Using production data and old gamma rays logs, a black oil reservoir model that honors both primary and secondary performance was developed. The old gamma ray logs were used after applying a resealing technique, which was crucial for the success of the project. In addition to the gamma ray logs, the development of the reservoir model benefitted from an inverse Drill Stem Test (DST) technique which provided initial estimates of the reservoir permeability at different wells.
Date: May 1, 1997
Creator: Weiss, W.W.; Buckley, J.S. & Ouenes, A.
Partner: UNT Libraries Government Documents Department

Investigation of radon, thoron, and their progeny near the earth`s surface. Final report, 1 January 1994--31 December 1997

Description: This is the final report for DOE Grant DE-FG03-94ER6178, covering a performance period of 1 January 1994 through 31 December 1997. The DOE award amount for this period was $547,495. The objective of the project as stated in its proposal was {open_quotes}to improve our understanding of the physical processes controlling the concentration of radon, thoron, and their progeny in the atmospheric environment.{close_quotes} The original project was directed at developing underlying science that would help with evaluation of the health hazard from indoor radon in the United States and implementation of corrective measures that might be employed to reduce the health hazard. As priorities within the Office of Health and Environment (OHER) changed, and the radon research program was phased out, emphasis of the project was shifted somewhat to be also relevant to other interests of the OHER, namely global pollution and climate change and pollution resulting from energy production. This final report is brief, since by reference it can direct the reader to the comprehensive research publications that have been generated by the project. In section 2, we summarize the main accomplishments of the project and reference the primary publications. There were seven students who received support from the project and their names are listed in section 3. One of these students (Fred Yarger, Ph.D. candidate) continues to work on research initiated through this project. No post-docs received support from the project, although one of the co-principal investigators (Dr. Piotr Wasiolek) received the majority of his salary from the project. The project also provided part-time support for a laboratory manager (Dr. Maryla Wasiolek). Section 4 lists chronologically the reports and publications resulting from the project (references 1 through 12), and the Appendix provides abstracts of major publications and reports.
Date: January 1, 1998
Creator: Schery, S.D. & Wasiolek, P.T.
Partner: UNT Libraries Government Documents Department

Determination of hydraulic conductivities of low permeability materials in the Sierra Ladrones Formation, Albuquerque basin

Description: Low permeability materials in the Sierra Ladrones Formation were sampled and analyzed to determine their hydraulic conductivities using the falling head centrifugation method (fc) as described by Nimmo et al. (1991). The method is similar to the traditional falling head method, only it uses greatly increased centrifugal forces, allowing measurements to make in a relatively short amount of time. Using these measurements, variations in saturated hydraulic conductivities between different sediment types were analyzed using Analysis of Variance (ANOVA). Sampling resulted in useable data chiefly from the clay and silt facies of the formation. The range of conductivities determined are representative of brown and red clays, and silts which make up the overbank deposits of this region. Hydraulic conductivities for these overbank fines were found to range from approximately log K = {minus}9 m/s to log K = {minus}7 m/s. The upper measurement limit of the centrifuge apparatus was determined to be approximately 1.43 {times} 10{sup {minus}7} m/s and the lower limit was approximately 7.6 {times} 10{sup {minus}12} m/s.
Date: June 1, 1995
Creator: Planert, C.S.
Partner: UNT Libraries Government Documents Department

A sedimentological approach to hydrologic characterization: A detailed three-dimensional study of an outcrop of the Sierra Ladrones Formation, Albuquerque basin

Description: Three-dimensional geologic outcrop studies which quantitatively describe the geologic architecture of deposits of a specific depositional environment are a necessary requirement for characterization of the permeability structure of an aquifer. The objective of this study is to address this need for quantitative, three-dimensional outcrop studies. For this study, a 10,000 m{sup 2} by 25 m high outcrop of Pliocene-Pleistocene Sierra Ladrones Formation located near Belen, New Mexico was mapped in detail, and the geologic architecture was quantified using geostatistical variogram analysis. In general, the information contained in this study should be useful for hydrologists working on the characterization of aquifers from similar depositional environments such as this one. However, for the permeability correlation study to be truly useful, the within-element correlation structure needs to be superimposed on the elements themselves instead of using mean log (k) values, as was done for this study. Such information is derived from outcrop permeability sampling such as the work of Davis (1990) and Goggin et al. (1988).
Date: January 1, 1992
Creator: Lohmann, R.C.
Partner: UNT Libraries Government Documents Department

PREP program annual report, 1994

Description: A total of thirty-three 9th and 10th grade American Indian students participated in the program. Curricular focal points were environmental science, supported by courses and labs in mathematics, technical writing, and chemistry. The 1994 summer program was the second year of the environmental science focus. The environmental component covered four topics during the month-long program: drinking water, waste water, solid waste pollution, and mining reclamation. The overall goal of the project was to encourage a greater number of the targeted high school students to acquire the necessary skills to succeed in rigorous college academic programs and to enter science-based disciplines. Students participating in the program were involved in a rigorous daily academic program of formal instruction. Participants lived in the residence halls and participated in many aspects of college life, including planned recreational activities. Students were also involved in academic year activities to maintain a heightened awareness and interest in science-based fields. These goals were met and the program was judged to be a success.
Date: December 31, 1994
Partner: UNT Libraries Government Documents Department

Improved efficiency of miscible CO{sub 2}, floods and enhanced prospects for CO{sub 2} flooding heterogeneous reservoirs. Quarterly technical progress report, October 1, 1995--December 31, 1995

Description: The objective of this experimental research is to improve the effectiveness of CO{sub 2} flooding in heterogeneous reservoirs. Activities are being conducted in three closely related areas: (1) exploring further the applicability of selective mobility reduction (SMR) in the use of foam flooding, (2) exploring the possibility of higher economic viability of floods at slightly reduced CO{sub 2} injection pressures, and (3) taking advantage of gravitational forces during low interfacial tension (IFT), CO{sub 2} flooding in tight, vertically fractured reservoirs.
Date: April 14, 1994
Creator: Grigg, R.B. & Schechter, D.S.
Partner: UNT Libraries Government Documents Department

Improved techniques for fluid diversion in oil recovery. Final report

Description: This three-year project had two technical objectives. The first objective was to compare the effectiveness of gels in fluid diversion (water shutoff) with those of other types of processes. Several different types of fluid-diversion processes were compared, including those using gels, foams, emulsions, particulates, and microorganisms. The ultimate goals of these comparisons were to (1) establish which of these processes are most effective in a given application and (2) determine whether aspects of one process can be combined with those of other processes to improve performance. Analyses and experiments were performed to verify which materials are the most effective in entering and blocking high-permeability zones. The second objective of the project was to identify the mechanisms by which materials (particularly gels) selectively reduce permeability to water more than to oil. A capacity to reduce water permeability much more than oil or gas permeability is critical to the success of gel treatments in production wells if zones cannot be isolated during gel placement. Topics covered in this report include (1) determination of gel properties in fractures, (2) investigation of schemes to optimize gel placement in fractured systems, (3) an investigation of why some polymers and gels can reduce water permeability more than oil permeability, (4) consideration of whether microorganisms and particulates can exhibit placement properties that are superior to those of gels, and (5) examination of when foams may show placement properties that are superior to those of gels.
Date: January 1, 1996
Creator: Seright, R.
Partner: UNT Libraries Government Documents Department

Field verification of CO{sub 2} Foam. Final report

Description: The East Vacuum Grayburg/San Andres Unit (EVGSAU), operated by Phillips Petroleum Company, was the site selected for a comprehensive evaluation of the use of foam for improving the effectiveness of a CO{sub 2} flood. This project, entitled {open_quotes}Field Verification of CO{sub 2-}Foam,{close_quotes} was jointly funded by the EVGSAU working interest owners, the U.S. Department of Energy (DOE), and the State of New Mexico. The DOE provided $2 million or approximately 34% of the total project costs, the EVGSAU provided $2.46 million, the State of New Mexico contributed approximately $1.2 million, and about $103,000 of other industrial funds were used. The Petroleum Recovery Research Center (PRRC), a division of the New Mexico Institute of Mining and Technology, provided laboratory and research support for the project. A joint project advisory team composed of technical representatives from several major oil companies provided input, review, and guidance for the project. The project, which began in 1989, had a scheduled duration of four years, but the DOE granted a no-cost extension to the end of March 1995 for the purpose of continued project evaluation. A field test of the CO{sub 2}-foam has been successfully conducted, and preliminary results are promising. Response in the foam injection well has been as anticipated, and an offset producing well experienced a positive oil response as a result of the foam test. Based on the favorable results observed in the foam injection test, a second foam test was conducted. The monitoring program included analysis of injectivity data, pressure falloff tests, observation well logs, interwell tracer response, production logs, history of production rates, and changes in gas-oil ratio. This report presents an overview of the project and provides results of the laboratory work, simulation studies, and field tests.
Date: February 1, 1996
Creator: Martin, F.D.; Heller, J.P. & Weiss, W.W.
Partner: UNT Libraries Government Documents Department

Nuclear magnetic resonance imaging of subsurface water content. 1997 annual progress report

Description: 'During the period from October 1997 to January 1998 the author has further developed the understanding of NMR physics, improved software for forward and inverse modeling of the NMR signal, and conducted field tests on sites in Colorado and New Mexico. One important result from the forward modeling was that the field strength of the signals is concentrated under the loop. This indicates that little lateral dissipation occurs. The author received the NUMIS/NMR system (manufactured by IRIS Instruments, France) in late July, 1997. In July and early August, 1997, potential test sites were visited, and several test sites were selected and permitted. The first NMR test measurements were made in mid-August, 1997. The instrument malfunctioned during mid-September, 1997, and was returned to IRIS for repairs. Time lost due to malfunction, repairs, and shipping was about one month. Many NMR measurements have been made at sites in Colorado and New Mexico. Parks often have been selected as test sites due to ease of permitting, the relatively large open space, and general lack of powerlines. Noise from power lines severely degrades the NMR data quality. The NMR data acquired at the first three sites in Colorado (Bear Creek, Clear Creek, and Prospect) was either severely distorted by powerline noise or did not indicate significant groundwater occurrences. The NMR data taken at Cherry Creek were of good quality and also indicated significant groundwater. The NMR data acquired at three sites with relatively shallow ground water levels around Socorro, New Mexico, did not detect any ground water due to severe signal distortion by magnetite, a magnetic mineral. Measurements in a compact sand stone near Santa Rosa and in a limestone near Artesia, New Mexico, gave excellent results. Overall, the NMR technique proves capable of detecting subsurface ground water under the right conditions: little noise ...
Date: January 1, 1997
Creator: Hendrickx, J.M.H.
Partner: UNT Libraries Government Documents Department

Improved efficiency of miscible CO{sub 2} floods and enhanced prospects for CO{sub 2} flooding heterogeneous reservoirs. Annual report, April 14, 1994--April 13, 1995

Description: The overall goal of this project is to improve the efficiency of miscible CO{sub 2} floods and enhance the prospects for flooding heterogeneous reservoirs. This objective is being accomplished by extending experimental research in three task areas: (1) foams for selective mobility control in heterogeneous reservoirs, (2) reduction of the amount of CO{sub 2} required in CO{sub 2} floods, and (3) miscible CO{sub 2} flooding in fractured reservoirs. This report provides results of the first year of the three-year project for each of the three task areas.
Date: September 1, 1995
Creator: Grigg, R.; Heller, J. & Schechter, D.
Partner: UNT Libraries Government Documents Department

Surface nuclear magnetic resonance imaging of water content distribution in the subsurface. 1998 annual progress report

Description: 'The objective of the project is to evaluate Surface Nuclear Magnetic Resonance Imaging ( NMRI) for determining water content distribution in the subsurface. In NMRI the interaction of the magnetic moment of hydrogen ( protons) nuclei with external applied electromagnetic ( EM ) fields is measured. In surface NMRI the Earth''s magnetic field causes alignment of the spinning protons. An alternating EM field is generated by a loop of wire laid on the Earth surface. The alternating current driven through the loop at the Lamor frequency of protons in liquid water. The component of the EM field perpendicular to the Earth''s field causes a precession of protons from thier equilibrium position. Water content distribution in the subsurface is derived from measurements on the EM field caused by the return of the precessing protons to equilibrium after the current in the transmitter loop is terminated. The scientific goals of the R and D are: to verify and validate the theoretical concepts and experimental results of Russian scientists, who first introduced this method; to evaluate the range of applications and limitations of this technology for practical field measurements. NMRI has the potential of providing a remote, direct, unique method for subsurface water measurements. All present methods are either intrusive or indirect ( e.g. electrical resitivity measurements). In the past year progress has been made along two separate paths. These are: (1) Field Measurements. Surface NMRI equipment manufactured by IRIS Instruments of France was tested over a number of sites with good hydrogeologic control. The results of these measurements can be summarized as follows: The NMRI measurement directly and uniquely determines water distribution in coarse grained aquifers; geologic formation from which water can be readily withdrawn. Water content can not be determined by this technique in fine grained sediments. The signal to be ...
Date: June 1, 1998
Creator: Hendrickx, J.M.H.
Partner: UNT Libraries Government Documents Department

Surfactant-modified zeolites as permeable barriers to organic and inorganic groundwater contaminants

Description: We have shown in laboratory experiments that natural zeolites treated with hexadecyltrimethylammonium (HDTMA) are effective sorbents for nonpolar organics, inorganic cations, and inorganic anions. Due to their low cost ({approximately}$0.75/kg) and granular nature, HDTMA-zeolites appear ideal candidates for reactive, permeable subsurface barriers. The HDTMA-zeolites are stable over a wide range of pH (3-13), ionic strength (1 M Cs{sup +} or Ca{sup 2+}), and in organic solvents. Surfactant-modified zeolites sorb nonpolar organics (benzene, toluene, xylene, chlorinated aliphatics) via a partitioning mechanism, inorganic cations (Pb {sup 2+}) via ion exchange and surface complexation, and inorganic anions (CrO{sub 4}{sup 2-}, SeO{sub 4}{sup 2-},SO{sub 4}{sup 2-}) via surface precipitation.
Date: December 1, 1995
Creator: Bowman, R.S. & Sullivan, E.J.
Partner: UNT Libraries Government Documents Department

New permeameters for in-situ characterization of unsaturated heterogeneous permeability. 1998 annual progress report

Description: 'Thick unsaturated zones underlie many Department of Energy (DOE) landfills, industrial areas, and waste storage sites in the western US and are the primary pathway for contaminants to migrate into underlying aquifers. The spatial variability of unsaturated hydraulic properties in these heterogeneous geologic materials directly influences the movement of water and non-aqueous phase liquids (NAPL''s). Poor characterization of heterogeneity may lead to ineffective remedial designs and increased risk, requiring subsequent additional remedial actions at increased cost and time. Remedial design can be improved using probabilistic risk-based decision analysis, which requires a large number of hydraulic property observations. Laboratory methods for estimating the unsaturated permeability are expensive, time-consuming, and may not yield results representative of heterogeneous field conditions. Simple and rapid field methods for estimating in-situ unsaturated permeability are appealing and potentially cost-effective. The primary objective of the EMSP research is to design, develop, and test new permeameters for use in spatial variability studies. The authors have established a series of permeameter design criteria, including: (1) measurements should be relatively rapid, (2) the total cost per data point should be low, (3) results would accurately reflect the variation of unsaturated hydraulic properties between sampled locations, (4) the volume sampled (measurement support) would be small, and (5) useful range would be relevant to the range of soil moisture conditions encountered at DOE sites. This report summarizes work after year two of a 3-year project. They report their activities to date related to development and testing of techniques for inverting permeameter data, development of numerical tools for data inversion, error evaluation for permeameter design, and permeameter component design.'
Date: June 1, 1998
Creator: Wilson, J.L.
Partner: UNT Libraries Government Documents Department

Integration of advanced geoscience and engineering techniques to quantify interwell heterogeneity. Quarterly technical report, July 1, 1995--September 30, 1995

Description: The objective of this project is to integrate advanced geoscience and reservoir engineering concepts with the goal of quantifying the dynamics of fluid-rock and fluid-fluid interactions as they relate to reservoir architecture and lithologic characterization. This interdisciplinary effort will integrate geological and geophysical data with engineering and petrophysical results through reservoir simulation. Several members of the PPRC staff are participating in the development of improved reservoir description by integration of the field and laboratory data, as well as in the development of quantitative reservoir models to aid performance predictions.
Date: December 1, 1995
Creator: Buckley, J.S.; Weiss, W.W. & Ouenes, A.
Partner: UNT Libraries Government Documents Department