United States Environmental Protection Agency Office of Research and Development Washington DC 20460 EPA/600/K-94/004 June 1994 Robert S. Kerr Environmental Research Laboratory Research Program ------- EPA/600/K-94/004 June 1994 Robert S. Kerr Environmental Research Laboratory Revised June 1994 Compiled by Robert S. Kerr Environmental Research Laboratory Office of Environmental Processes and Effects Research Office of Research and Development U.S. Environmental Protection Agency Ada, Oklahoma 74820 Printed on Recycled Paper ------- CONTENTS RSKERL Background 1 USEPA Office of Research and Development 3 RSKERL Organizational Chart 4 Active Projects 5 Project Descriptions Site Characterization 15 Contaminant Transport and Transformation 24 Subsurface Remediation 33 Underground Injection Control 59 Wellhead Protection 60 Mathematical Modeling 67 Technical Assistance and Information Transfer 77 Publications (1992-1994) 78 ni ------- RSKERL BACKGROUND The enactment of the Federal Water Pollution Control Act in 1961 provided for the construction of a number of regional laboratories to address increasing water pollution problems indigenous to the areas they would serve. In 1966 one of these was placed in Ada, Oklahoma. It was named for Robert S. Kerr, a long time U.S. Senator from the State, in honor of his dedication and concern for conservation and the development of our natural water resources and his pioneering environmental legislation. Initially the Laboratory provided technical assistance, presented training, and conducted research to solve water pollution problems in Arkansas, Louisiana, New Mexico, Oklahoma, and Texas. In 1970, the Laboratory's role was expanded and it became one of fifteen research facilities administered through EPA's Office of Research and Development in Washington, D.C. In 1979, the Robert S. Kerr Environmental Research Laboratory (RSKERL) was designated as EPA's center for ground-water research by the Assistant Administrator of the Office of Research and Development. Today the Laboratory focuses its activities on research, technical assistance, and information transfer in the areas of soil and ground-water protection and restoration. Although the research activities at RSKERL are extremely varied, they center in great measure on understanding, modeling, and applying the basic principles involved in the physical, chemical, and biological processes which control contaminant transport and transformation in the subsurface. For the purposes of this document, the active research investigations are discussed according to the following categories. Site Characterization Contaminant Transport and Transformation Subsurface Remediation Underground Injection Control Wellhead Protection Mathematical Modeling In addition to its inhouse researchers and support personnel, the RSKERL research mission is advanced by a cadre of extramural researchers representing universities, national laboratories, other federal agencies, the National Center for Ground Water Research, and on-site contractors. RSKERL currently has more than 50 active research projects. In addition to those being carried out by RSKERL scientists, others under the auspices of the Laboratory are being carried out in 18 states while working with 22 Universities, 7 other federal agencies, and 3 state agencies. RSKERL is conducting research cooperatively with Canada, Sweden, and the People's Republic of China. Technical assistance at RSKERL falls within the purview of the Technology Support Center (TSC) which carries out its mission in close association with the Laboratory's research scientists. Assistance is provided by direct participation in field investigations and decision criteria primarily at specific Superfund and RCRA sites. Assistance is also provided to Regions, States, and municipalities related to the underground injection control and wellhead protection programs. Technology transfer endeavors include issue papers and briefing documents, workshops, seminars, conferences, and training courses. The RSKERL Technology Support Center consists of a core team of scientists and engineers supported by RSKERL and extramural researchers, the National Center for Ground Water ------- Research, the RSKERL Center for Subsurface Modeling Support (CSMoS), and an on-site technology support contractor with off-site subcontractors and consultants. The RSKERL TSC is discussed in greater detail elsewhere in this document. While many inroads have been made toward the solution of environmental problems, new challenges are now in evidence for which there are no immediate answers. In addition to the myriad of hazardous waste sites which have contaminated the subsurface environment, other agricultural and domestic practices graphically illustrate a lack of knowledge concerning the disposal of waste products and the protection of ground-water quality. ------- U.S. Environmental Protection Agency Office of Research and Development Assistant Administrator for Research and Development J. Office of Modeling Monitoring Systems & Quality Assurance Office of Environmental Processes & Effects Research Office of Environmental Engineering & Technology Demonstration Office of Health & Environmental Assessment Office of Health Research Athens Environmental Research Laboratory Duluth Environmental Research Laboratory Gulf Breeze Environmental Research Laboratory R.S. Kerr Environmental Research Laboratory Corvallis Environmental Research Laboratory Narragansett Environmental Research Laboratory ------- Robert S. Kerr Environmental Research Laboratory Organizational Chart Office of the Director Clinton W. Hall Director Administrative Support Staff Jimmie L. Kingery Chief Processes and Systems Research Division Dr. Stephen G. Schmelling Director Extramural Activities and Assistance Division Marion R. Scalf Director Subsurface Processes Branch Dr. Michael D. Jawson Chief Subsurface Systems Branch Vacant Extramural Activities and Evaluation Branch James F. McNabb Chief Applications and Assistance Branch John E. Matthews Chief 4 ------- ACTIVE PROJECTS Site Characterization Hydrological Studies and Data Base Development for the Walnut Creek Watershed in Support of the MASTER Project USDA - National Soil Tilth Laboratory 15 The Impact of Agriculture on Subsurface Ecology Purdue University 16 Assessment of the Hydrology of Walnut Creek Watershed near Ames, Iowa USDA - National Soil Tilth Laboratory 16 Landscape Classification for Ground-Water Row and Nitrogen Load Modeling (Chesapeake Bay Watershed) USGS Towson, Maryland 17 Fracture Characterization and Fluid Flow National Research Council/National Academy of Sciences 17 Reclamation by Biopiling of Excavated Soil Contaminated with Semivolatile Petroleum Organics University of Texas 17 Laser Fluorescence EEM Probe for Cone Penetrometer Pollution Analysis Tufts University 18 Stable Isotope Evaluation of Soil Metal Speciation by Selective Extraction U.S. Army Corps of Engineers - Waterways Experiment Station 18 Capture Zone Delineation in a Fractured Carbonate Aquifer Undecided 19 Characterization of the Test Site at Hill AFB for the Demonstration of Enhanced Source Removal for Aquifer Restoration TyndallAFB 19 Implications of Colloidal Mobility for the Collection of Representative Ground Water Samples Cooperative Agreement 20 Mobilization of Naturally Occurring Heavy Metals by Reductive Dissolution Cooperative Agreement 20 ------- Ground Water Sampling RSKERL 20 Evaluation of Methods of DNAPL Site Characterization Cooperative Agreement 21 Site Characterization Using a Cone Penetrometer RSKERL 21 Dielectric and Resistivity Method for Detecting Nonaqueous-Phase Liquid Contaminants in Multiphase Systems RSKERL 21 Environmental Buffer Criteria for the Assessment of Soil Quality in Agroecosystems USDA 22 Subsurface Ecology RSKERL 22 Geohydrology and Nitrate Loadings of the Ground-Water Systems Impacting the Chesapeake Bay RSKERL 23 Site Characterization Using a Hydraulically Driven Soil Gas and Ground-Water Probe RSKERL 23 Contaminant Transport and Transformation Separation and Identification of Aquifer Organic Matter ManTech/RSKERL 24 Characterization of Organic Matter in Soils and Aquifer Solids Western Michigan University 25 Assimilative Capacity of Subsurface for the Pesticides Atrazine, Alachlor, and Nitrate USDA - National Tilth Laboratory 25 Spectroscopic Studies of Organic Films on Mineral Surfaces ManTech/RSKERL 26 Augmenting Natural Recharge of Ground Water with Reclaimed Wastewater, Stormwater, and Irrigation Return Flow National Academy of Sciences 26 ------- Three-Dimensional Modeling of Subsurface Flow, and Fate and Transport of Microbes and Chemicals Penn State University 27 Validation of the Approximate Multiphase Flow Models RSKERL 27 Heavy Metal Transport in a Sand and Gravel Aquifer with Variable Chemical Conditions U.S. Geological Survey 28 Transport and Transformation of Arsenic and Chromium in Ground Water RSKERL 28 Compilation of Saturated/Unsaturated Zone Models and Development and Application of Testing Methods and Benchmark Cases Colorado School of Mines 29 Subsurface Processes Controlling Sorption and Transport of lonizable and Polar Organic Compounds University of Florida 29 Use of the Assimilative Capacity Concept to Develop Agrichemical Usage Guidance and Determine the Fate of Atrazine in a Wet Meadow in the Central Platte Valley Alluvium of Nebraska Nebraska Department of Environmental Quality 30 Subsurface Transport Properties in Layered Media RSKERL 30 Laboratory Electronic Measurements and Data Collection Systems for RSKERL Artificial Aquifers RSKERL/ManTech 31 Transformation of Pesticides RSKERL 31 Biodegradation of Pesticides in Aquifers RSKERL/ManTech 32 Subsurface Remediation Anaerobic Processes in the Subsurface Environment RSKERL 33 ------- Surfactant Enhanced Solubilization of Chlorinated Hydrocarbons RSKERL 34 Field-Evaluation of Cosolvent-Enhanced In-situ Remediation University of Florida 34 Development of a Data Evaluation/Decision Support System for Bioremediation of Subsurface Contamination Rice University 34 Assessment of Solvent-Enhanced Desorption and Mobilization of Polychlorinated Biphenyls RSKERL 35 Rapid Phase Identification of Mixed Crystalline Solids Using Surface Analytical Techniques for Assessment of In-Situ Aquifer Remediation Oregon Graduate Institute 35 Decision Support System for Evaluating Remediation Performance with Interactive Pump-and-Treat Simulator Rice University 36 Modeling and Design of Bioremediation Systems for a JP-4 Jet Fuel Spill at Eglin AFB, Florida Rice University 36 Studies on the Sulfur Mediated Biological Denitrification Process Orange County Water District 37 Innovative Methods for Remediation of Subsurface Chromium Contamination Rice University and University of Oklahoma 37 Microbial Characterization and Treatability Study for a JP-4 Jet Fuel Spill at Eglin AFB, Florida Rice University 38 Great Plains-Rocky Mountain Hazardous Substance Research Center, U. of Iowa University of Iowa 38 Response of Subsurface Microbial Communities to the Introduction of Contaminants Cooperative Agreement 39 Surfactant Enhanced Remediation of Subsurface DNAPL Contamination University of Oklahoma 39 ------- Evaluation of Technologies for Cleanup of DNAPL Contaminated Sites University of California 40 Site Characterization of Ground-Water Row and Transport in Fractured Rock Systems for Improvement of Pump-and-Treat Remediation Lawrence Berkeley Laboratory 40 Investigation of Surfactant Enhanced Remediation of Aquifers Contaminated by Dense, Non-Aqueous Phase Liquids (DNAPLs) University of Michigan 41 Super Computer Simulation of Pump-and-Treat Methods for Aquifer Restoration University of North Carolina - Chapel Hill 41 Artificial Aquifer Studies - East Aquifer ManTech/RSKERL 42 Passive Anaerobic Remediation of BTEX Compounds in Ground Water North Carolina State University 42 Forced Aeration for On-Site Remediation of Hydrocarbon Spills U.S. Park Service 43 Design and Operating Parameters for the Remediation of a Fuel Oil Contaminated Soil Using Composting Technology Howard University 43 Remediation of Contaminated Soils by Solvent Flushing University of Florida 44 Microbial Metabolism of Munitions Wastes in Anoxic Aquifers Rice University 44 Three-Dimensional NAPL Fate and Transport Model University of Texas 45 Methods for Determining Multiphase Characteristic Curves for Use in Designing Subsurface Bioremediation Systems University of California at Davis 45 Development of a Data Evaluation/Decision Support System for Bioremediation of Subsurface Contamination MIT 45 ------- Development of Techniques for In Situ Bioremediation of Chromium Contaminated Soil and Ground-water: Phase I Laboratory Evaluation University of Oklahoma Bioremediation of BTEX, Naphthalene, and Phenanthrene in Aquifer Material Using Mixed Oxygen/Nitrate Electron Acceptor Conditions Johns Hopkins University [[[ Bioremediation of Fuel-Contaminated Aquifers Using Mixed Electron Acceptor Conditions University of Waterloo [[[ Evaluation of In-Situ Bioremediation of Chlorinated Hydrocarbon Contaminated GW at Air Force Plant 44 Western Region Hazardous Substance Research Center, Stanford University ............................... 47 H202 and Microbial System Interactions RSKERL/ManTech [[[ 48 A Pilot-Scale Demonstration of Surfactant-Enhanced Subsurface Remediation of Chlorinated Hydrocarbons University of Oklahoma [[[ 48 China-US Soils & Ground Water Remediation Research Sino-US International Agreement [[[ 49 Treatment of Process Off-Gases Contaminated with TCE Using Ex-Situ Soil Based Aerobic Bioreactors USGS [[[ 49 Evaluation of Passive Remediation Techniques at Mixed-Waste Sites Using Geochemical Barriers Cooperative Agreement [[[ 49 Design Manuals for the Extraction of Contaminants from Unconsolidated Subsurface Environments ------- Oxygen Consumption in Clay Soils Contaminated by #2 Fuel Oil RSKERL 51 Chemically Enhanced Dissolution and Mobilization of Residual Contaminants RSKERL 51 Remediation of Chromium Contaminated Soils and Ground Water at a Chrome Plating Site RSKERL 52 Sorption of Polar Organic Compounds to Colloidal Particles RSKERL 52 Pore-Scale Investigation of the Behavior of Remedial Fluids Cooperative Agreement 52 Changes in Subsurface Wetting Behavior in the Presence of NAPLs RSKERL/ManTech 53 Abiotic Reduction of Chrome from Zero-Valence Iron Dissolution RSKERL/ManTech 53 Evaluation of Proposed Closure Criteria at Remediated Sites Cooperative Agreement 54 Natural Attenuation of Ground Water Contaminants at Air Force Installations RSKERL (US Air Force) 54 Denitrification for Bioremediation of a Refinery Spill Park City, Kansas RSKERL 55 Bioventing to Remediate a JP-4 Spill at the USCG Site at Elizabeth City, North Carolina RSKERL 55 Feasibility Study on Enhancement of Nitrate-Based Bioremediation Using Surfactants RSKERL 56 Vinyl ChlorideVTCE at St. Joseph, MI Site RSKERL 56 Aerobic Co-Oxidation of TCE Vapors RSKERL 56 Reductive Anaerobic Biological In-Situ Treatment RSKERL 11 ------- Petroleum Hydrocarbon Biodegradation Under Mixed Denitrifying/Microaerophilic Conditions RSKERL 57 Prepared Bed Bioremediation in Buried Lifts as Affected by O2 Concentrations in Soil Gas Utah State University 5? Biological Treatment of Trichloroethylene Contaminated Process Off-Gas U.S. Army Corps of Engineers Waterways Experiment Station 58 Underground Injection Control Injection Well Mechanical Integrity East Central University 59 Potential for Invasion of Underground Sources of Drinking Water Through Mud-Plugged Wells: An Experimental Appraisal Oklahoma State University 59 Wellhead Protection Hydrogeologic Mapping to Delineate Wellhead Protection Zones Around Springs State of Utah 60 The Development of a Risk Management Strategy for Wellhead Protection University of Miami 60 Determination of Subsurface Assimilative Capacity RSKERL 61 Delineation of Wellhead Protection Zones: Consideration of Virus Transport University of Arizona 61 Demonstration of the Analytical Element Method for Wellhead Protection Indiana University 62 Capture Zone Delineation: Models and Experiments New Mexico Institute of Mining and Technology 62 Capture Zone Delineation Using the EPA WHPA Model and Other Codes: A Comparative Study in Ellis County, Kansas RSKERL 63 12 ------- Technical Assistance and Technology Transfer in Wellhead Protection RSKERL 63 Contaminant Identification and Classification University of Oklahoma 64 Ground-Water Flow in a Carbonate Aquifer, Southern Oklahoma USGS 64 System Analysis for Evaluating Aquifer Assimilative Capacity Rice University Consortium 65 Economic Value of Ground Water National Research Council 65 Risk Management Decision Support System (RMDSS) for Wellhead Protection RSKERL 66 Mathematical Modeling Multiphase Flow in Soils: Modeling and Experimental Study University of Colorado 67 Three-Dimensional Modeling of Subsurface Flow, and Fate and Transport of Microbes and Chemicals Penn State University 67 Validation of the Approximate Multiphase Flow Models RSKERL 68 Three-Dimensional Multiphase Flow and Contaminant Transport Mathematical Model University of Vermont 68 Screening Methods for Hydrocarbon Spills and Recovery Rice University and University of Texas 69 Compilation of Saturated/Unsaturated Zone Models and Development and Application of Testing Methods and Benchmark Cases Colorado School of Mines 69 Evaluation of Ground-Water Pump-and-Treat Systems at the Gilson Road Superfund Site, Nashua, NH, with Ground-Water Models University of Cincinnati 70 13 ------- Application of Electromagnetic Tomography to Monitoring DNAPL University of Arizona 70 Four-Dimensional Electrical Imaging of Subsurface Contaminants with Applications to a Controlled Spill Massachusetts Institute of Technology 71 A Computer Program to Model Bioventing of Organic Contaminants in Unsaturated Geological Material University of Michigan 71 Modeling Flow through Fractured Media-Testing Continuum vs. Discrete Conceptualizations RSKERL 72 Evaluation of Multiphase Flow and Transport Models in a Large Two-Dimensional Physical Model Cooperative Agreement 72 Determination of Mass Transfer Rates between Mobile/Immobile Soil-Air Regions RSKERL 72 Evaluation of Dual Source Gamma Ray Absorption System RSKERL 73 Development of Lagrangian Methods for Subsurface Contaminant Transport Analysis RSKERL 73 Soil Vacuum Model RSKERL 73 Intermediate-Scale Evaluation of Subsurface Transport and Fate Models Cooperative Agreement 74 Parameter Sensitivity Evaluation of Selected Unsaturated Zone Models RSKERL 74 Sensitivity of Model Predicted Chemical Transport to Boundary Conditions at the Soil Surface RSKERL 74 BIT Inverse Solution RSKERL 75 14 ------- SITE CHARACTERIZATION Site characterization research is conducted in order to improve the ability to assess risks associated with a contaminated site, evaluate the need for corrective action, and select as well as evaluate the effectiveness of proper remediation technologies. Exposure assessments must be based on an awareness of the geologic, hydrologic, geochemical, and biological characteristics of the site. Research in this area is aimed at the development of methods of investigation and interpretation in order to determine the parameters which describe a site and define their spatial distribution. Hydrological Studies and Data Base Development for the Walnut Creek Watershed in Support of the MASTER Project INSTITUTE USDA National Soil Tilth Laboratory (Michael Jawson, P.O.) TASK NO: 1067 PROJECT PERIOD: 03/92 09/94 PRINCIPAL INVESTIGATOR: J.L. Hatfield (515)294-5723 ABSTRACT: With respect to hydrological studies, the object of the project is to quantify the coupling between the ground and surface water in the upper reaches of the Walnut Creek watershed and the movement of water in the shallow alluvium. Also included is the assessment of ground-water flow and quality in the Skunk River alluvium. Available information on ground-water will be compiled with respect to agricultural chemicals in the Western Cornbelt Ecoregion. Data elements collected by each MASTER investigator will be incorporated into a compatible and accessible data base for use by all investigators. 15 ------- The Impact of Agriculture on Subsurface Ecology INSTITUTE: Purdue University (Michael Jawson, P.O.) TASK NO: 1072 PROJECT PERIOD: 10/92 09/94 PRINCIPAL INVESTIGATOR: Ronald Turco (317) 494-8077 ABSTRACT: The objectives of the project are assess community diversity and size, and develop a set of ecological indicators that can be used to estimate the environmental status of the subsurface and changes which occur as a consequence of environmental stresses, particularly those resulting from agricultural chemicals and practices. The spatial variability in microbial activity and community structure will also be assessed. Microbial community structure and metabolic processes will be determined using root zone, vadose zone, and aquifer samples at the Indiana Water Quality Field Station and an Iowa Midwest System Evaluation Area site. Microbial community structure will be analyzed using whole bacteria population DNA-reassociation curves to assess species diversity, percent G+C content by DNA the bisbenzimide binding method to assess the bacterial community makeup, and phospholipid fatty acid pattern (PLFA) and fatty acid methyl ester (FAME) analysis to assess bacterial biomass size and community composition. Metabolic process studies will be used to assess the response to stresses imposed by agrichemicals. Microcosm samples will be spiked with radiolabelled 2,4-D and catechol. Small-scale spatial variability will be assessed using samples taken horizontally from the root and vadose zones which will be analyzed by PLFA and FAME procedures to determine microbial community structure, and 2,4-D mineralization to determine microbial activity. A final report on the impact of agriculture on subsurface ecology will be completed in December, 1994. Assessment of the Hydrology of Walnut Creek Watershed near Ames, Iowa INSTITUTE: USDA National Soil Tilth Laboratory (Steve Kraemer, P.O.) TASK NO: 1084 PROJECT PERIOD: 07/93 06/95 PRINCIPAL INVESTIGATOR: M.R. Burkhart (515) 294-5809 ABSTRACT: The specific objectives of this project include: (1) conduct a hydrogeologic reconnaissance of the watershed; (2) determine the ground water/surface water interactions in proximity of the Walnut Creek channel; (3) determine the influence of the loss of water in the stream bed on the Skunk River alluvial aquifer; (4) extend the development of the analytic element ground-water model of the watershed; and (5) screen, document, and qualify data that will be used to meet the objectives of MASTER and MSEA. Outputs of the project will be GIS coverages and Journal Articles. 16 ------- Landscape Classification for Ground-Water Flow and Nitrogen Load Modeling (Chesapeake Bay Watershed) INSTITUTE: USGS Towson, Maryland (Steve Kraemer, P.O.) TASK NO: 1085 PROJECT PERIOD: 10/93 09/94 PRINCIPAL INVESTIGATOR: L. Bachman (401)828-1535 ABSTRACT: The objective of this project is to associate land use patterns with ground-water nitrate loadings to the Chesapeake Bay. The initial effort is on data reconnaissance and database creation. A hydrogeomorphic landscape classi- fication system based on multivariate statistics is proposed. Outputs will include a Database and ARC/INFO CIS coverages. Fracture Characterization and Fluid Flow INSTITUTE National Research Council/National Academy of Sciences (Stephen Schmelling, P.O.) TASK NO: 2052 PROJECT PERIOD: 07/91-05/93 PRINCIPAL INVESTIGATOR: Peter Smealie (202) 334-3137 ABSTRACT: The purpose of this study is to review, synthesize, and integrate recent research concerning techniques and approaches to fractured rock characterization and fluid flow in fractured geologic settings. A committee composed of approximately 10 recognized experts from the fields of geology, geomechanics, geophysics, hydrology, and geochemistry met July 23-26, 1991, to review the status of current research, identify problem areas, explore mechanisms to advance the field, and offer guidance to federal agencies. The work will culminate in a report on Fracture Characterization and Fluid Flow. Reclamation by Biopiling of Excavated Soil Contaminated with Semivolatile Petroleum Organics INSTITUTE: University of Texas (Don Kampbell/John Matthews, P.O.) TASK NO: 2065 PROJECT PERIOD: 08/92 - 08/97 PRINCIPAL INVESTIGATOR: Ray Loehr (512)471-5602 ABSTRACT: The objective of the project is to develop emergency response technology on the rate and extent of bioremediation of soil containing crude oil or heavy refined petroleum products by treatment cell bioventing at field spill sites. The first step of the project will be to locate a field site suitable for research studies. The contaminated material will be excavated and transferred to a forced aeration soil pile constructed on site. Kinetics information on depletion will be determined and compared with laboratory data. A Final Report of research activities will be completed. 17 ------- Laser Fluorescence EEM Probe for Cone Penetrometer Pollution Analysis INSTITUTE: Tufts University (Bob Lien, P.O.) TASK NO: 3076 PROJECT PERIOD: 10/93 09/96 PRINCIPAL INVESTIGATOR: J. Kenny (617) 627-3397 ABSTRACT: Locating and mapping the distribution of oily phase material in the subsurface is one of the most difficult and uncertain processes in the Remedial Investigation process at hazardous waste sites. Traditional methods using hollow stem auger rigs and core samples are much too expensive for extensive mapping of wastes. Monitoring wells often fail to detect oily phase material. Recently, multi-sensor cone penetrometers have been developed for hazardous waste characterization. Existing proof-of-concept cone penetration sensor modules have been developed that introduce a fiber optic cable into the subsurface with the cone penetrometer. Lasar light beamed down the fiber optic cable illuminates the subsurface material adjacent to the cone through a sapphire window. Certain oily wastes, such as TCEand naphthalene, will fluoresce. The fiber optic cable collects the fluorescence and brings it back to the surface for analysis by a spectrophotometer. Existing equipment is specific on one type of waste. This project will develop and field test a Raman shifter that will allow multiple channel spectral analysis of the returned fluorescence. This will allow for the simultaneous analysis of several compounds (up to ten) with different fluorescence responses. The following outputs will be produced: A user's manual for the new sensor system and a final report, describing the field scale performance of the new sensor system during characterization of oily waste at a hazardous waste site. Stable Isotope Evaluation of Soil Metal Speciation by Selective Extraction INSTITUTE: U.S. Army Corps of Engineers Waterways Experiment Station (Robert Puls, P.O.) TASK NO: 3084 PROJECT PERIOD: 09/93 09/94 PRINCIPAL INVESTIGATOR: M. Bricka (601) 634-3799 ABSTRACT: Reliable, validated methods to discriminate between forms of metals in soil would be extremely valuable for assessing hazards of metals contaminated sites and evaluating alternatives for soil remediation. Extraction methods for isolating metals associated with various soil components have been used for many years to make decisions on soil nutritional status, toxicity, and environmental mobility. Unfortunately, very little definitive work has been performed to ascertain the validity and shortcomings of these extraction techniques. Stable isotope studies on model and amended natural soils offer a tool to investigate the selectivity and completeness of selective extraction techniques, and thus evaluate the usefulness of extraction in metal speciation/contaminated soil characterization. Inductively coupled plasma/mass spectrometry (ICP/MS) provides the analytical selectivity and sensitivity needed to effectively conduct the isotope studies. The proposed work would combine the analytical advantages of ICP/MS with metal stable isotope experimentation to evaluate and improve the usefulness of soil extraction procedures for metals speciation. A Final Report on Stable Isotope Evaluation of Soil Metal Speciation by Selective Extraction will be prepared. 18 ------- Capture Zone Delineation in a Fractured Carbonate Aquifer INSTITUTE: Undecided TASK NO: 0384-001 PROJECT PERIOD: Proposal PRINCIPAL INVESTIGATOR: ABSTRACT: The objective of this task is to examine the capture zone of a pumping well in a carbonate aquifer. The project will integrate computer modeling with field observations. The field component will be broadly multidisciplinary including remote sensing, surface and borehole geophysics, and aquifer testing. The modeling component will emphasize both conceptual modeling and code development and application. Characterization of the Test Site at Hill AFB for the Demonstration of Enhanced Source Removal for Aquifer Restoration INSTITUTE: Tyndall AFB (Carl Enfield, P.O.) TASK NO. 0935-003 PROJECT PERIOD: 04/94 - 09/94 PRINCIPAL INVESTIGATOR: Capt. Jeffrey Stinson (904) 283-6254 ABSTRACT: An essential part of any aquifer remediation project is a site characterization that provides the information necessary to select, design, operate, and evaluate an appropriate remedial technology. Before the field demonstrations can be conducted, the test site must likewise be thoroughly characterized. Site characterization will involve the use of ground- penetrating radar, cone penetrometer, fiber optic spectroscopy, and possibly seismic techniques. The entire project will involve two different test sites to determine the feasibility of a number of technologies to enhance the performance of pump-and-treat systems. The first test site will be at Hill AFB, the second has yet to be determined. 19 ------- Implications of Colloidal Mobility for the Collection of Representative Ground Water Samples INSTITUTE: Cooperative Agreement TASK NO: 0940-001 PROJECT PERIOD: Proposal PRINCIPAL INVESTIGATOR: ABSTRACT: The objective of this project is address the implications of colloidal mobility on the collection of ground water samples. The research would address factors such as the effects of low-flow purging and sampling techniques on sample quality, filtration effects, sampling methodologies in fractured rock, and sampling methodologies in tight formations. This project will complement ongoing in-house research at RSKERL. The investigation will result in a Project Report and Research Brief. Mobilization of Naturally Occurring Heavy Metals by Reductive Dissolution INSTITUTE: Cooperative Agreement TASK NO: 0940-002 PROJECT PERIOD: Proposal PRINCIPAL INVESTIGATOR: ABSTRACT: The objective of this project will be to investigate those specific geochemical factors that promote surface chemical reactions that mobilize naturally occurring arsenic and other heavy metals at waste disposal sites. The approach will be largely laboratory based and will be coordinated with work at field sites where this phenomenon has been observed. Ground Water Sampling INSTnUTE: RSKERL TASK NO: 0940-RSRP5 PROJECT PERIOD: 01/94 - 06/96 PRINCIPAL INVESTIGATOR: Robert Puls (405) 436-8543 ABSTRACT: The objective of this project is determine the impacts of different sampling methodologies and devices on contaminant concentrations in recovered ground-water samples. The approach will be to conduct field and laboratory studies to compare different sampling devices as well as different sampling methodologies. The investigation will result in a Project Report and a Research Brief. 20 ------- Evaluation of Methods of DNAPL Site Characterization INSTITUTE Cooperative Agreement TASK NO: 0946-005 PROJECT PERIOD: Proposal PRINCIPAL INVESTIGATOR: ABSTRACT: The objective of this project is to evaluate innovative direct and indirect methods that have been proposed or recently developed to characterize hazardous waste sites contaminated by DNAPLs. A Project Report or Research Brief, and an Issue Paper will be prepared. Site Characterization Using a Cone Penetrometer INSTITUTE: RSKERL TASK NO: 0946-RSBL1 PROJECT Period: 08/93 09/95 Principal INVESTIGATOR: Bob Lien (405) 436-8555 ABSTRACT: The objective of this project is to develop methods and techniques for site characterization at hazardous waste sites using a cone penetrometer testing system. The development of methodology for site characterization will involve: (1) literature reviews, (2) basic cone penetrometer testing at local field site, (3) development of a site characterization strategy, (4) development and integration of innovative sensor modules, (5) upgrading of data acquisition systems, and (6) proof-of-concept field testing of an innovative cone penetrometer system at hazardous waste sites. Dielectric and Resistivity Method for Detecting Nonaqueous-Phase Liquid Contaminants in Multiphase Systems INSTITUTE: RSKERL TASK NO: 0946-RSBL2 PROJECT PERIOD: 10/93 09/96 PRINCIPAL INVESTIGATOR: Bob Lien (405) 436-8555 ABSTRACT: The objective of this project is to investigate the feasibility of applying dielectric and resistivity methods to detection of nonaqueous phase liquid (NAPL) contamination at hazardous waste sites. The feasibility of using dielectric and resistivity methods for detecting NAPL contamination will be evaluated in both laboratory and field experiments. Laboratory column studies will be used to determine the feasibility and sensitivity of dielectric and resistivity methods. If these prove successful, the next step will be to construct probes that can be used with a cone penetrometer and test them in the field. 21 ------- Environmental Buffer Criteria for the Assessment of Soil Quality in Agroecosystems INSTITUTE: USDA (Michael Jawson, P.O.) TASK NO: 3190-001 PROJECT PERIOD: Proposal PRINCIPAL INVESTIGATOR: ABSTRACT: Soil, because of its position n the interface between air and water as well as its function in altering the composition and availability of air and water, is crucial to ecosystem well being. Soil is the basic resource necessary for sustainable agricultural systems, purifying water and support of terrestrial life. One of the major functions of soil is as an environmental buffer. This function is especially important in agroecosystems because of the intentional releases and stresses from agrichemicals. This recognition of the importance of soil in an ecosystem context is unfortunately quite recent and although implicitly recognized throughout the ages in terms of crop production it is not until recently (within the last 2 years) the concept and term "soil quality" has received attention of the soil science community. Criteria and methods to quantify soil quality are just beginning. This task is focused on determining the criteria important to the environmental buffer component of soil quality and will be tied into efforts where the sustainable agriculture component is being conducted. The research will result in a journal article on environmental buffer criteria for soil quality indexes and a report that assesses soil quality from an ecological effects view point. Subsurface Ecology INSTITUTE: RSKERL TASK NO: 3190-RPMJ3 PROJECT PERIOD: 01/94 06/94 PRINCIPAL INVESTIGATOR: Michael Jawson (405) 436-8560 ABSTRACT: Determining ecological effects is a foremost scientific priority of EPA. The subsurface, considered here to extend from the soil surface through the saturated zone, is a basic component of the global ecosystem. Unfortunately, despite the essential roles played by subsurface ecosystems, it is the least characterized, quantified and appreciated component of the ecosystem. Despite our lack of knowledge of this environment, the subsurface receives more waste and contaminants annually by weight than any other medium. Life as we know it would not be possible without the biogeochemical cycling and other functions performed by subsurface microorganisms, yet only 5% of the earth's microbial species are known. Determining ecosystem risk will not be possible until the characteristics and activities of the subsurface component are quantified. This project is focused on the following two themes: (1) quantification of transformations within the subsurface and of the fluxes of materials to other ecosystem components; and (2) characterization of the subsurface ecosystem including the development of ecocriteria. Needed is an understanding of the subsurface components, both biotic and abiotic, and their interrelationships. Lack of knowledge about the structure and diversity of the subsurface has two important impacts. First, we do not have bioindicators (ecocriteria) of environmental stress in the subsurface and, therefore, must depend upon direct contaminant detection - a trying task given the physical, spatial and temporal obstacles. Secondly, modeling the processes and predicting risks is quite limited without an understanding of subsurface communities, their geo-physical and chemical environment, and their interactions with the other components of the ecosystem. A journal article on the importance of the subsurface in ecosystem analyses will be prepared as well as a report for the MASTER program that provides an assessment of subsurface (soil) quality at the Walnut Creek, Iowa MSEA site. 22 ------- Geohydrology and Nitrate Loadings of the Ground-Water Systems Impacting the Chesapeake Bay INSTITUTE: RSKERL TASK NO- 3192-RSSK4 PROJECT PERIOD: 11/93 09/96 PRINCIPAL INVESTIGATOR: Steve Kraemer (405) 436-8549 ABSTRACT: The objective of this RSKERL in-house research project is to develop understanding of the hydrologic interactions between Atlantic Coastal Plain aquifers and the Chesapeake Bay and its tidal and non-tidal rivers, and use this understanding to estimate the potential loadings of nitrate via ground-water pathways. Computer models are being built to represent the shallow geohydrologic systems at the ground-water shed and drainage basin scales. A mass balance for nitrate will be estimated using the modeling approach. This research is being performed in collaboration with the USGS (Towson.MD) through Interagency Agreement. A USEPA Project Summary and Research Report on the Geohydrology and Nitrate Loadings of the Ground Water Systems Impacting the Chesapeake Bay will be prepared. Site Characterization Using a Hydraulically Driven Soil Gas and Ground-Water Probe INSTITUTE: RSKERL TASK NO: 3364-RPDK2 PROJECT PERIOD: 10/92 12/95 PRINCIPAL INVESTIGATOR: Don Kampbell (405) 436-8561 ABSTRACT: Most conventional site characterization is two dimensional, while the distribution of contamination in aquifers is strongly three dimensional. New tools are needed that allow vertical characterization of the extent of contamination. This task will evaluate the Geoprobe, a new tool on the market that can rapidly and economically sample soil gas, ground water, and sediments from shallow unconsolidated aquifers. The tool also allows a measure of the local hydraulic or pneumatic conductivity at the depth interval that produces a sample. Field work will be conducted as an in- house research project by EPA staff. The following outputs will be produced, including: Text and slides for a training course on the use of a Geoprobe for site characterization and a journal article describing the use of the Geoprobe to determine the fluid flow properties of the subsurface. 23 ------- CONTAMINANT TRANSPORT AND TRANSFORMATION Research is aimed at describing the hydrologic, abiotic, and biotic processes which influence contaminant transport and transformation characteristics in the subsurface environment. A knowledge of subsurface transport and transformation processes is the foundation for all environmental protection activities related to the subsurface. The more commonly occurring processes are reasonably well understood, but predictions can only be made with reasonable certainty for simple hydrogeologic systems and dissolved contaminants. The knowledge of many other transport and transformation processes is emerging from laboratory and small-scale preliminary field experiments, but is not yet at a point where it can be generalized for routine application to remediation or prevention activities. Examples include facilitated colloidal transport, contaminant transport in complex wastes, gas-phase transport and transformation, subsurface transport of microorganisms, the interaction of separate processes, and natural degradation. Separation and Identification of Aquifer Organic Matter INSTITUTE: RSKERL/ManTech (Candida West/Roger Cosby, P.O.) TASK NO: 1051 PROJECT PERIOD: 03/90 10/94 PRINCIPAL INVESTIGATOR: Bill Lyon (405) 436-8666 ABSTRACT: The objects of this project are to: (1) test density methods for separation of aquifer organic matter from sandy aquifer material; (2) scale-up the process to obtain sufficient material for bulk measurements; (3) obtain pyrolysis-GC/MS patterns for comparison to soil organic matter; (4) obtain IR and elemental analysis of the aquifer organic matter; and, (5) apply techniques to analyze the pyrolysis and IR data. The purpose of the project is to obtain analytical data that can be used to study the basic characteristics of aquifer organic matter in order to: (1) determine the validity of the normalization of sorption coefficients by total organic carbon for aquifer organic matter; and, (2) compare the variability in composition of aquifer organic matter to soil organic matter. Milestones include progress reports on GC-Pyrolysis and IR/Elemental Analysis. A final internal report will be prepared on the Separation and Identification of Aquifer Organic Matter. 24 ------- Characterization of Organic Matter in Soils and Aquifer Solids INSTITUTE: Western Michigan University (Candida West, P.O.) TASK NO: 1053 PROJECT PERIOD: 03/91 03/94 PRINCIPAL INVESTIGATOR: Michael Barcelona (616) 387-5501 ABSTRACT: The overall goals of the project are to develop and test a systematic methodology to characterize the organic matter in subsurface soil and aquifer solids. The methodology should provide a means to identify and quantify natural and anthropogenic organic matter in solid materials. A characterization methodology will be developed using TOC/TIC analyses, carbon isotopic methods to determine relative amounts of natural and anthropogenic organic compounds, and extraction techniques to determine sorbed, bound, and occluded fractions and the identification of specific organic compounds. In addition to interim reports, a final report will be prepared on Characterization of Organic Matter in Soils and Aquifer Material. Assimilative Capacity of Subsurface for the Pesticides Atrazine, Alachlor, and Nitrate INSTITUTE: USDA/National Soil Tilth Laboratory (Michael Jawson, P.O.) TASK NO: 1069 PROJECT PERIOD: 08/92 0/95 PRINCIPAL INVESTIGATOR: Thomas Moorman (515) 294-2308 ABSTRACT: Sites in Iowa, Minnesota, Missouri, Nebraska, and Ohio will be utilized to: (1) quantify the fate of atrazine and alachlor including their principal metabolites; (2) determine the kinetics of degradation or immobilization processes for atrazine and alachlor, and (3) determine if reliable indexes of assimilative capacity can be identified or developed. An integrated mass balance approach is being used to determine the fate of the herbicides. Measurements of parent compounds provided data on the amount of readily extractable and presumably available and/or leachable unaltered pesticide. The measurement of principal metabolites will supply data on the extent transformation proceeds to these intermediate stages. The measurement of 14CO2 provides an indication of the amount of mineralization of the parent compound while the residual I4C provides information on the amount of compound bound to surfaces and organic matter and presumably unavailable to microorganisms or leaching. The Iowa Walnut Creek watershed will be used to: (1) determine the denitrification potential in the intermediate vadose zone, and (2) determine the denitrification activity in the upper reaches of the water table, and evaluate the source of the electron donors for this process. A series of incubation treatments and nitrate amendments will be used to determine factors limiting denitrification. Investigations will also be carried out to determine the magnitude of denitrification and the electron donor involved in the process. 25 ------- Spectroscopic Studies of Organic Films on Mineral Surfaces INSTITUTE: RSKERL/ManTech (Candida West/Roger Cosby, P.O.) TASK NO: 1078 PROJECT PERIOD: 01/91 09/94 PRINCIPAL INVESTIGATOR: Bill Lyon (405) 436-8666 ABSTRACT: The project is designed to expand the current understanding of natural and anthropogenic organic carbon coatings on aquifer solid matrices and their capacity to retard the movement of organic contaminants in the subsurface. Artificial and natural coatings of humic and other organic materials will be characterized and studied spectroscopically. Sorption experiments will be conducted. Augmenting Natural Recharge of Ground Water with Reclaimed Wastewater, Stormwater, and Irrigation Return Flow INSTITUTE: National Academy of Sciences (Carl Enfield, P.O.) TASK NO: 1083 PROJECT PERIOD: 10/93 - 08/94 PRINCIPAL INVESTIGATOR: C. Elfring (202) 334-3422 ABSTRACT: The objective of this project is to have an expert panel assess the current state of knowledge relative to the use of reclaimed wastewater, storm water, and irrigation return flows to augment natural recharge of ground waster. 26 ------- Three-Dimensional Modeling of Subsurface Flow, and Fate and Transport of Microbes and Chemicals INSTITUTE: Perm State University (Thomas Short, P.O.) TASK NO: 2055 PROJECT PERIOD: 10/91 10/94 PRINCIPAL INVESTIGATOR: George Yeh (814) 863-2931 ABSTRACT: The objectives of this project are to develop a three-dimensional numerical algorithm for the solution of the saturated-unsaturated transport equations for multiple components that undergo mutual reactions based on the LEZOOM approach and to analyze test data produced from physical model aquifers at RSKERL. A mathematical code will be developed which is capable of simulating experimental runs on RSKERL physical model aquifers. The results produced by the code will be compared with experimental data to determine if the proposed mathematical description of the mechanisms involved is adequate. A report with the same title as the project will be prepared. Validation of the Approximate Multiphase Flow Models INSTITUTE: RSKERL TASK NO: 2059 PROJECT PERIOD: 09/91 10/94 PRINCIPAL INVESTIGATOR: James Weaver (405) 436-8545 ABSTRACT: The object of the project is to test the KOPT (Kinematic Oily Pollutant Transport) portion of the HSSM (Hydrocarbon Spill Simulation Model) by comparison with laboratory data. Several oils will be released into specially designed columns which are packed with various porous media. The ponding depth and depth of the oil front will be recorded as functions of time. Independent measurements of the model parameters will be made on the column. The average values of the parameters will be used as KOPT model input data. The model results will be compared with the laboratory data experiments. Monte Carlo simulation will be used to assess the impact of uncertainty in the values of the parameters. 27 ------- Heavy Metal Transport in a Sand and Gravel Aquifer with Variable Chemical Conditions INSTITUTE: U.S. Geological Survey TASK NO: 2075 PROJECT PERIOD: 07/92 06/95 PRINCIPAL INVESTIGATOR: James Davis FTS: 459-4484 ABSTRACT: The objectives of the work are to obtain a more complete understanding of the geochemical processes that effect metal transport in ground water and the mechanisms that couple these processes with hydrologic processes. A large- scale tracer test will be conducted at the Otis Air Force Base USGS Field Site on Cape Cod in Massachusetts. This will be the first such large-scale tracer test performed using conservative and conservatively transported metal contaminants in such a highly instrumented field site. The large-scale tracer test will exploit the vertical gradient in ground-water chemistry at the site to study transport under variable chemical conditions. Prior small-scale tracer tests and related laboratory experiments will be analyzed to determine the exact composition of the tracer injections to achieve the stated objectives. Following the injection, subsequent sampling and data interpretation will follow for more than 14 months. Reactive transport modeling of the test will then be initiated. Products of the investigation will include a journal article describing the transport of chromium (VI), a journal article describing the transport of copper and zinc, and a final environmental research brief. Transport and Transformation of Arsenic and Chromium in Ground Water INSTITUTE: RSKERL TASK NO: 2082 PROJECT PERIOD: 12/93 12/96 PRINCIPAL INVESTIGATOR: Robert Puls (405) 405-8543 ABSTRACT: The objective of this project is to determine the chemical and microbiological factors controlling arsenic and chromium transport and transformation on subsurface environments. Data will be collected in laboratory experiments using core material from hazardous waste sites where elevated levels of arsenic and chromium are observed to elucidate the processes responsible for their mobilization and transport. A journal article will completed at the end of the project. 28 ------- Compilation of Saturated/Unsaturated Zone Models and Development and Application of Testing Methods and Benchmark Cases INSTITUTE: Colorado School of Mines (James McNabb, P.O.) TASK NO: 3038 PROJECT PERIOD: 10/91 - 09/94 PRINCIPAL INVESTIGATOR: Paul van der Heijde (303)273-3800 ABSTRACT: The objectives of this project are to enhance the existing knowledge of ground-water models and their utility and performance, develop guidance in applying quality assurance in model development, and address other scientific issues related to the use of ground-water models. The approach to carrying out this project will be: (1) to enhance existing data bases on ground-water models, (2) characterize and analyze models for their utility and performance, (3) develop and apply testing and validation procedures to prominent public domain models, (4) develop and provide detailed guidance in the development of models, and (5) develop issue papers on critical topics in ground-water modeling. A Report on Analytical Solutions will be prepared along with a Report on the Status of Ground-Water Models. Subsurface Processes Controlling Sorption and Transport of lonizable and Polar Organic Compounds INSTITUTE: University of Florida (Susan Mravik, P.O.) TASK NO: 3083 PROJECT PERIOD: 10/93 09/96 PRINCIPAL INVESTIGATOR: P. Nkedi-Kizza (904) 392-1951 ABSTRACT: The objective of this project is to collect data on the mechanisms for the sorption of polar and ionizable organic compounds to subsurface materials. These data will be used to develop mechanistic models of the sorption process which can be used in subsurface transport and fate models. Batch and column studies will be used to provide data on both the extent and kinetics of the sorption process. 29 ------- Use of the Assimilative Capacity Concept to Develop Agrichemical Usage Guidance and Determine the Fate of Atrazine in a Wet Meadow in the Central Platte Valley Alluvium of Nebraska INSTITUTE: Nebraska Department of Environmental Quality (Michael Jawson, P.O.) TASK NO: 5002 PROJECT PERIOD: 10/93 - 09/95 PRINCIPAL INVESTIGATOR: D. Jenson (402) 471-4700 ABSTRACT: This project supports two of Region VII's strategic directions for FY93-96: (1) Pesticide and Nitrate Risk Reduction and (2) Ecosystem Assessment and Protection (the Platte River Ecosystem Management Initiative). It also implements EPA's strategic themes of improved science/data, pollution prevention, and geographic targeting on an ecosystem basis. This project has two major objectives: (1) to study the transport and fate of atrazine in ground water through a selected wet-meadow area in the central Platte valley of Nebraska and (2) to develop decision aids to guide agrichemical usage which take into account the environment's assimilative capacity. A set-meadow area within the Kearney-to-Grand Island reach of the Platte valley will be selected for study. The wet meadow will be immediately downgradient from rowcrop-production land on which atrazine (and probably other chemicals) has been applied. Although data from adjacent areas likely will be useful, the primary study area will be an elongate area on the order of 0.5 mile along a ground-water flow path. A network of observation-well nests will be installed, for which water-level and water-quality data will be obtained to define spatial variations and seasonal and shorter-term temporal variations. The network will consist of about eight nests of two wells each. Age-dating and tracer techniques will be used to help determine flow patterns and velocities. Chemical parameters measured in the field will be temperature, specific conductance, pH, and dissolved oxygen. An immunoassay method will be used on all samples to determine atrazine and associated compounds semiquantitatively: GC-MS and complete inorganic chemical analyses will be conducted on selected samples. In addition, agrichemical usage guidance based upon assimilative capacity will be developed by the University of Nebraska-Lincoln Agronomy Department. Using an expert systems type of approach, the known effects of environmental parameters (such as pH, temperature, clay, and organic matter content) on agrichemical dissipation and transformation will be used to develop the decision aids for application levels of agrichemicals taking into account the amount of attenuation that occurs between the application point and the receptor locations (e.g., the water resources of the Platte Basin the Platte River, wetlands, and ground water). Outputs will include a Report and journal article on the fate of atrazine in wetlands and a Guidance document (e.g., decision aid fact sheet) and report on agrichemical use which will protect ground and surface waters." Subsurface Transport Properties in Layered Media INSTITUTE: RSKERL TASK NO: 0932-1001 PROJECT PERIOD: Proposal PRINCIPAL INVESTIGATOR: ABSTRACT: The objective of this project is to conduct laboratory experiments to elucidate subsurface transport properties that result from the strong horizontal layering that is commonly found in natural geologic environments. This project will coordinate in-house EPA research and work with an extramural organization. 30 ------- Laboratory Electronic Measurements and Data Collection Systems for RSKERL Artificial Aquifers INSTITUTE: RSKERL/ManTech TASK NO: 0946-1003 PROJECT PERIOD: Proposal PRINCIPAL INVESTIGATOR: ABSTRACT: The objective of this project is to design, assemble, install, and evaluate measurement systems that can be used to collect electromagnetic tomography and time domain reflectometry systems data for the movement of nonaqueous- phase liquids (NAPLs) in RSKERL's large physical models. Transformation of Pesticides INSTITUTE: RSKERL TASK NO: 3191-RPMJ2 PROJECT PERIOD: 01/94 12/95 PRINCIPAL INVESTIGATOR: Michael Jawson (405) 436-8560 ABSTRACT: The objective of this task is to tie together RSKERL's pesticide projects to ascertain the comprehensive fate of pesticides in relationship to their vertical environment (surface soil, vadose zone and saturated zone) across an extensive (mid continent) area. This should also enable predictions to be made as to the transfer of the pesticides to other environmental media. When the results from all the studies in this project are available, the data will be analyzed to discern the "big picture" in terms of which factor determines the fate and assimilative capacity of the pesticides studied. Appropriate statistical and other data analysis approaches will be utilized after consultation with statisticians and QA specialists to resolve the comprehensive fate of these pesticides. The work will result in a report, journal articles, and decision support systems on the environmentally acceptable usage of pesticides. 31 ------- Biodegradation of Pesticides in Aquifers INSTITUTE: RSKERL/ManTech TASK NO: 3191-RE104 PROJECT PERIOD: Proposal PRINCIPAL INVESTIGATOR: • ABSTRACT: It is well established that the rate of biodegradation of xenobiotic organic substances decreases below the root zone. Relatively little work has been done on the fate of pesticides in the subsurface, however. Available studies have indicated that the rate of pesticide biodegradation also declines with depth. The objectives of this project are to determine if pesticide biodegradation occurs in the subsurface, at what rate, and what the products of the biodegradation are. These experiments are being carried out in sediments from several sites. Site specific differences as well as the history of pesticide application and other factors may affect the rate of pesticide biodegradation. Atrazine is only one of several pesticide contaminants of ground water, and its behavior in subsurface samples may differ from that of other pesticides. To find out how other pesticides besides atrazine biodegrade in subsurface samples, several known pesticide contaminants of ground water were selected for pesticide experiments. A journal article and report on the fate of pesticides in aquifer materials will be prepared. 32 ------- SUBSURFACE REMEDIATION In addition to developing technologies which protect and restore the subsurface environment, research in this area must assure that such methods are cost effective without being unnecessarily complex, and do not unduly resrtict other land use activities. Anaerobic Processes in the Subsurface Environment INSTITUTE: RSKERL TASK NO: 1041 PROJECT PERIOD: 03/89 10/95 PRINCIPAL INVESTIGATOR: Guy Sewell (405) 436-8566 ABSTRACT: Anaerobic conditions predominate in contaminated aquifers and are common in uncontaminated areas. Comparatively little is known about degradative processes and nutrient cycling under anaerobic conditions. However, it is apparent that these processes are fundamentally different and more complex than aerobic processes. The objective of this research is to define and study anaerobic microbial metabolic processes which occur in the subsurface environment to further understand the fate of contaminants in that environment. Three areas will be investigated using microbiological, biochemical, and molecular biological techniques, with emphasis in three major areas: 1. Metabolism of aromatic compounds under sulfate reducing conditions. In this study the breakdown and metabolism of fuel aromatics (primarily benzene, toluene, and xylenes) by sulfate-reducing isolates and consortia will be examined. 2. Metabolic processes at the aerobic/anaerobic interface. The role of mixed aerobic/anaerobic conditions on the metabolism of organic compounds is unclear. An attempt will be made to identify and spatially locate the processes and microbes which exist at and near the interface. 3. Effects of altered oxidation/reduction balance on anaerobic metabolism. Anaerobic chemoheterotrophs generate useable metabolic energy (ATP or electro-chemical gradients) from oxidizable substrates via fermentation or anaerobic respiration. Alterations in the O/R balance of these organisms may broaden the range of electron donors and acceptors. Project outputs to date include an Article on Reductive Dechlorination of Tetrachloroethane and Trichloroethane in Fuel Spill Plumes, and a Journal Article on Reductive Dechlorination. A journal article is under way on Anaerobic Degradation. 33 ------- Surfactant Enhanced Solubilization of Chlorinated Hydrocarbons INSTITUTE: RSKERL TASK NO: 1068 PROJECT PERIOD: 02/91 - 09/94 PRINCIPAL INVESTIGATOR: Candida West (405) 436-8551 ABSTRACT: The objective of the investigation is to examine interactions between chlorinated solvents and non-ionic surfactants in solution with emphasis being on determining the fundamental relationship between contaminant water solubility and structures on contaminant solubilization. Initial, batch sorption experiments will be conducted tq determine solubilization of PCE, TCE, and DCE by selected surfactants. After single solute systems are completed a series of experiments will then be carried out to determine the effect of multiple solutes and temperatures on the solubilization of the solutes by the same series of surfactants. Field-Evaluation of Cosolvent-Enhanced In-situ Remediation INSTITUTE: University of Florida (Lynn Wood, P.O.) TASK NO. 1086 PROJECT PERIOD: 10/93 10/95 PRINCIPAL INVESTIGATOR: M. Annable (904) 392-3294 ABSTRACT: The objective of this project is to evaluate the feasibility of using miscible organic cosolvents such as alcohols to remediate subsurface environments contaminated by hydrophobic organic chemicals. The project will be carried out as a pilot-scale field study using sheet piling cells to provide hydraulic containment. A Report on the Feasibility of using Organic Cosolvents to Enhance Removal of Hydrophobic Organic Compounds will be prepared. Development of a Data Evaluation/Decision Support System for Bioremediation of Subsurface Contamination INSTITUTE: Rice University (Mary Randolph, P.O.) TASK NO. 1087 PROJECT PERIOD: 10/93 09/96 PRINCIPAL INVESTIGATOR: P. Bedient (713) 527-4953 ABSTRACT: Develop a computer based system which will accept both "hard" and "soft" data, in three-spatial dimensions plus time and allow interpretation into a conceptual model(s) of the hydrogeologic environment. It is desirable to be able to display graphically the confidence in the conceptual model(s) based on sound statistical techniques. Visualization of the conceptual model(s) will be on a platform. A Data Evaluation/Decision Support System for Bioremediation of Subsurface Contamination will be developed. 34 ------- Assessment of Solvent-Enhanced Desorption and Mobilization of Polychlorinated Biphenyls INSTITUTE: RSKERL TASK NO: 2062 PROJECT PERIOD: 02/91 09/94 PRINCIPAL INVESTIGATOR: Lynn Wood (405) 436-8552 Susan Mravik (405) 436-8553 ABSTRACT: The objectives of this project are to assess the efficacy of solvent mixtures for desorbing and mobilizing polychlorinated biphenyls (PCBs) in contaminated soils and aquifer materials and to formulate a strategy for optimizing contaminant mobilization in laboratory systems. Soils and aquifer materials contaminated with PCBs will be obtained from appropriate field sites. Selected batch equilibration tests will be conducted as a screening tool to determine equilibrium distribution constants for various cosolvent mixtures and to assist in the selection of appropriate column experiments. Dynamic column experiments will be the primary technique used to evaluate solvent-mediated desorption and mobilization. These experiments will be used to determine cosolvency parameters for solvent/solute/sorbent systems used in the study, to assess the impact of nonequilibrium sorption on PCB removal, and to evaluate the effects of solvents on the inherent sorptive and hydrodynamic properties of the sorbents. If initial laboratory results are promising, and if support and funding are available, this technique will be evaluated in larger and more realistic systems in the laboratory or field. A Journal Article Describing the Experimental Procedures and Initial Results of Solvent Enhanced Desorption of PCBs will be written. This will be followed at the end of the project by a Journal Article on the Impact of Solvents on the Rate of PCB Desorption. Rapid Phase Identification of Mixed Crystalline Solids Using Surface Analytical Techniques for Assessment of In-Situ Aquifer Remediation INSTITUTE: Oregon Graduate Institute (Bob Puls, P.O.) TASK NO: 2066 PROJECT PERIOD: 07/92 02/94 PRINCIPAL INVESTIGATOR: Carl Palmer (503) 690-1977 ABSTRACT: The objective of this investigation is to develop computer software techniques at metal sites for scanning tunneling microscopy with x-ray analysis for rapid and routine use as a site characterization and aquifer remediation assessment tool. 35 ------- Decision Support System for Evaluating Remediation Performance with Interactive Pump-and-Treat Simulator INSTITUTE: Rice University (David Burden/Dick Scalf, P.O.) TASK NO: 2069 PROJECT PERIOD: 09/92 09/94 PRINCIPAL INVESTIGATOR: Philip Bedient (713) 527-4953 ABSTRACT: The goal of the project is to develop a Decision Support System (DSS) for evaluating the effectiveness of pump-and-treat networks at Superfund sites. The approach is divided into two phases. Phase I focuses on developing the architecture and the different components of the DSS utilizing the OASIS system computing environment. Phase II involves porting the DSS into the PC environment. Extensive research and evaluation of programming tools will be completed in Phase I to ensure that portability can be successfully implemented in Phase II. An interim DSS report will be completed in late 1993 and the final DSS delivery will be completed approximately one year later. Modeling and Design of Bioremediation Systems for a JP-4 Jet Fuel Spill at Eglin AFB, Florida INSTITUTE: Rice University (James McNabb/Stephen Hutchins, P.O.) TASK NO: 2073 PROJECT PERIOD: 11192 11 /95 PRINCIPAL INVESTIGATOR: Herb Ward (713) 527-4086 Philip Bedient (713) 527-4953 ABSTRACT: The objective of the project is to use site characterization and modeling to provide design for bioremediation systems to be used in field demonstration project "Nitrate-Based Bioremediation, Eglin Air Force Base." Cone penetrometery, aquifer tests, and infiltration tests will be conducted at the Eglin AFB to obtain physical and chemical information on the aquifer. This information will be used in modeling to design a spray irrigation/recirculation system for nitrate-based bioremediation treatment for iron precipitation. An interim nitrate-based bioremediation design report will be prepared followed by the final evaluation/corrective measures design in October 1994. 36 ------- Studies on the Sulfur Mediated Biological Denitrification Process INSTITUTE: Orange County Water District (Stephen Hutchins, P.O.) TASK NO: 2074 PROJECT PERIOD: 10/92 - 09/94 PRINCIPAL INVESTIGATOR: Mike Davidson (714)963-5661 ABSTRACT: The objective of the project is to conduct studies on denitrification with autotrophic microorganisms which use inorganic sulfur as an energy source, and to incorporate these process parameters into a reactor design for treatment of nitrate-contaminated ground water. Batch tests will be conducted to delineate basic process control parameters and reaction kinetics, and column studies will be conducted to evaluate reactor design and systems performance. If time permits, a laboratory-scale, complete treatment unit incorporating biological process and ion exchange will be constructed to test the treatment strategy and provide data for economic assessment. A final report on the feasibility of this treatment train will be prepared. Innovative Methods for Remediation of Subsurface Chromium Contamination INSTITUTE: Rice University and University of Oklahoma (James McNabb, Robert Puls, P.O.) TASK NO: 2079 PROJECT PERIOD: 09/72 08/95 PRINCIPAL INVESTIGATOR: Herb Ward (713) 527-4086 David Sabatini (405)325-5911 ABSTRACT: The project is designed to determine an optimal system that will significantly enhance the remediation of subsurface environments contaminated with chromium. Laboratory batch and column tests will be used along with some field testing to assess chromium desorption from soils and sediments and chromate recovery from contaminated ground water. 37 ------- Microbial Characterization and Treatability Study for a JP-4 Jet Fuel Spill at Eglin AFB, Florida INSTITUTE: Rice University (Stephen Hutchins, P.O.) TASK NO: 2080 PROJECT PERIOD: 11/92 11/95 PRINCIPAL INVESTIGATOR: Herb Ward (713) 527-4086 J.M. Thomas ABSTRACT: The objective of the project is to conduct treatability studies to evaluate and optimize the remedial design and to determine the effects of nitrate-based bioremediation on the microbial ecology of subsurface material contaminated with JP-4 jet fuel. RSKERL will conduct an in-depth laboratory treatability study to determine the feasibility of using nitrate- based bioremediation for aquifer restoration at Eglin AFB, FL. Rate constants will be used to design the remediation system. Rice University will conduct microbial characterization during the project to assess changes in microbial ecology and ecotoxicity once remediation is complete. The treatability studies will be completed in June 1994, and the final project report will be issued in July 1995. Great Plains-Rocky Mountain Hazardous Substance Research Center, U. of Iowa INSTITUTE: University of Iowa (John Wilson, P.O.) TASK NO. 2084 PROJECT PERIOD: 10/93 05/94 PRINCIPAL INVESTIGATOR: L. Erickson (913) 532-5584 ABSTRACT: The objectives of the proposed research include the following: (1) to determine the effect of redox conditions (electron acceptor) on transformation of CT; (2) to identify pathways and metabolites of CT transformation; (3) to investigate the abiotic degradation of CT under reduced conditions; and (4) to determine the effect of CT concentration on transformation of CT. A progress report on modeling development will be developed. 38 ------- Response of Subsurface Microbial Communities to the Introduction of Contaminants INSTITUTE Cooperative Agreement (Guy Sewell, P.O.) TASK NO. 2085 PROJECT PERIOD: 09/95 09/96 PRINCIPAL INVESTIGATOR: Undecided ABSTRACT: The introduction of soluble contaminants into ground water initiates a series of complex and poorly understood responses by subsurface microorganisms. Field and laboratory research suggests that multiple, physiologically- defined-communities develop which are spatially and chronologically separate. These communities are most likely ecologically defined by the flux of biologically available electron donors and acceptors. Contaminants may serve as electron donors (e.g., fuel components), as electron acceptors (e.g., nitrate) or as both (e.g., 3,4-D). These biological processes are potentially useful as natural attenuation mechanisms and as indicators of the extent and severity of the release. The objective of this program will be to develop biological markers for native and contaminant induced microbial populations and to develop a conceptual model for the ecology of contaminant impacted populations in the subsurface and for native degradative capacities. A Report on the Conceptual Model and Final Report of Study will be prepared. Surfactant Enhanced Remediation of Subsurface DNAPL Contamination INSTITUTE: University of Oklahoma (Candida West, P.O.) TASK NO: 3035 PROJECT PERIOD: 11/91 10/94 PRINCIPAL INVESTIGATOR: David Sabatini (405)325-5911 ABSTRACT: The project is designed to develop an environmentally acceptable surfactant system for enhancing pump-and- treat remediation technology specifically for dense, nonaqueous phase liquids. The approach involves measuring the efficiency and effectiveness of specific classes of surfactant systems for solubilizing and mobilizing residual and free phase DNAPLs. Studies will be conducted to test chosen systems for ionic matrix sensitivities, biodegradability, solid phase interactions and transport properties. Two outputs will result from this effort including a Journal Article on DNAPL/Surfactant/Soil Interactions from Batch Studies, and an Environmental Research Brief on Surfactant Enhanced Remediation of Subsurface DNAPL Contamination. 39 ------- Evaluation of Technologies for Cleanup of DNAPL Contaminated Sites INSTITUTE: University of California (Steve Schmelling, P.O.) TASK NO: 3039 PROJECT PERIOD: 09/91 - 06/93 PRINCIPAL INVESTIGATOR: Nicholas Sitar (415) 643-8623 ABSTRACT: The project is designed to prepare a comprehensive assessment of the current state of in-situ treatment technologies for the remediation of ground-water contaminated by DNAPLs. A review and compilation of information on in-situ DNAPL treatment technologies will be followed by an assessment of the applicability and limitations of these technologies. A synthesis of this information will be presented in a Final Report. Site Characterization of Ground-Water Flow and Transport in Fractured Rock Systems for Improvement of Pump-and-Treat Remediation INSTITUTE: Lawrence Berkeley Laboratory (Steve Kraemer, P.O.) TASK NO: 3040 PROJECT PERIOD: 10/91 09/94 PRINCIPAL INVESTIGATOR: Kenzi Karasaki (415) 486-4289 ABSTRACT: The project is designed to investigate the effects of fractured network complexity on the efficiency of the pump-and-treat methods of aquifer remediation. The approach is to make a step-wise progressive analysis of fractured rock conceptualizations against field observations and experiments. Geophysical and hydrologic tests will be compared to computer model simulations. A final report describing the Behavior of Pump-and-Treat Systems in Fractured Rock Settings. 40 ------- Investigation of Surfactant Enhanced Remediation of Aquifers Contaminated by Dense, Non-Aqueous Phase Liquids (DNAPLs) INSTITUTE University of Michigan (Candida West, P.O.) TASK NO: 3041 PROJECT PERIOD: 10/91 09/94 PRINCIPAL INVESTIGATOR: Linda Abriola (383) 763-9664 ABSTRACT: The objective of this investigation is to develop procedures for the design of effective, efficient, and environmentally sound surfactant enhanced aquifer remediation (SEAR) strategies. Using two model DNAPLs, surfactant systems will be systematically examined with respect to solubilization and mobilization enhancement. Various parameter effects such as system temperature, ionic strength, Krafft temperature, and cloud point and sorptive properties will be examined. After selection of an "optimal" surfactant system using batch and column experiments, model validation will be explored. A Research Brief will be prepared on the Design of Effective, Efficient, and Environmentally Sound Surfactant Enhanced Aquifer Remediation (SEAR) Strategies. Super Computer Simulation of Pump-and-Treat Methods for Aquifer Restoration INSTITUTE: University of North Carolina - Chapel Hill (Eva Davis, P.O.) TASK NO: 3042 PROJECT PERIOD: 10/91 08/93 PRINCIPAL INVESTIGATOR: Cass Miller (919) 966-2643 ABSTRACT: The objectives of this project are to evaluate through a modeling exercise alternative pumping schemes for enhancing pump-and-treat ground-water remediation systems. Models will be used that take into account heterogeneity i n the subsurface and non-ideal chemical transport phenomena, such as non-linear and non-equilibrium adsorption. A second objective is to evaluate the capital and operating costs associated with these alternative pump-and-treat schemes. The approach to be used for this project is to use 2- and 3-dimensional flow and transport models to simulate the effects of various conditions on pump-and-treat ground-water remediation. The analysis will include evaluation of different initial source conditions, different types of contaminants (NAPLs), and the effects of alternative pumping rates and schedules. Heterogeneity of the subsurface physical and chemical parameters, such as hydraulic conductivity, and sorption parameters and rates, will also be evaluated. An economic analysis will be performed for all simulations to show the cost for remediation as a function of the pump-and-treat scheme used. A Report on Enhancing the Efficiency of Pump-and-Treat Systems will be prepared. 41 ------- Artificial Aquifer Studies - East Aquifer INSTITUTE: ManTech/RSKERL (Carl Enfield/Roger Cosby, P.O.) TASK NUMBER: 3046 PROJECT PERIOD: 10/91 12/94 PRINCIPAL INVESTIGATOR: Debra Ross (405) 436-8677 ABSTRACT: The project aim is to evaluate the transport and fate of dense nonaqueous phase liquids (DNAPL) which are spilled or have leaked into the subsurface. Techniques for monitoring the flow of DNAPLs will be developed and evaluated as part of the experimental project. The remediation of the subsurface by means of pump-and-treat systems, vapor phase extraction, and surfactant addition will also be studied. Conductivity, time domain reflectometry, and conductivity tomography probes have been installed in the artificial aquifer. The hydraulic properties of the aquifer will be determined using tritium or conductivity tracer studies. DNAPL selection and method of application is to be determined by the use of applicable numerical models. A final DNAPL migration report will be prepared. Passive Anaerobic Remediation of BTEX Compounds in Ground Water INSTITUTE: North Carolina State University (John Wilson, P.O.) TASK NO: 3060 PROJECT PERIOD: 10/92 09/94 PRINCIPAL INVESTIGATOR: Robert Borden (919)515-7665 ABSTRACT: The objective of the investigation is to generate data on the rate and extent of passive anaerobic bioremediation of BTEX compounds in ground-water plumes from fuel spills. The existing data base will be extended by examining plumes in more heavily weathered geological material with lower pH and little buffering capacity. Laboratory microcosm and field studies will be performed to determine the rate and extent of passive anaerobic bioremediation of BTEX compounds. Laboratory studies will be done with core material from existing plumes which show evidence of anaerobic processes. Field studies will compare the kinetics of depletion along flow paths in plumes to the laboratory data. An Internal Report will be completed followed by a Final Report 07/94. 42 ------- Forced Aeration for On-Site Remediation of Hydrocarbon Spills INSTITUTE: U.S. Park Service (Don Kampbell, P.O.) TASK NO: 3061 PROJECT PERIOD: 08/92 07/95 PRINCIPAL INVESTIGATOR: S. Yancho (616)362-5134 » ABSTRACT: The project is designed to develop, implement, and evaluate a system for on-site remediation of geological materials contaminated with fuel spills. A demonstration will be conducted at the Casey's Canoe Livery Site at Sleeping Bear Dunes National Lakeshore, Empire, Michigan. Contaminated material will be excavated and transferred to a forced aeration soil pile constructed on site. The Park Service and their contractor will develop and implement the system. A university researcher in Michigan will do the evaluation with support from the Great Lakes and Mid Atlantic Hazardous Research Center. An 08/92 Preliminary Internal Report will be followed by a Final Report in 08/94. Design and Operating Parameters for the Remediation of a Fuel Oil Contaminated Soil Using Composting Technology INSTITUTE: Howard University (John Wilson/Dale Manty, P.O.) TASK NO: 3066 PROJECT PERIOD: 05/92 08/94 PRINCIPAL INVESTIGATOR: James Johnson (202) 806-6570 ABSTRACT: The investigation will assess and determine the feasibility of composting fuel contaminated soil on site, as an alternative to excavation and removal or incineration. It will also provide engineering design parameters for a field- scale demonstration of forced aeration composting of a fuel spill. Soil from the demonstration site will be characterized. A laboratory-scale compost reactor will be used to define optimum operating ranges for moisture, aeration, bulking agents, inocula, and control of volatile emissions. A journal article on composting technology will be prepared. 43 ------- Remediation of Contaminated Soils by Solvent Flushing INSTITUTE: University of Florida (Lynn Wood, P.O.) TASK NO: 3069 PROJECT PERIOD: 10/92 03/94 PRINCIPAL INVESTIGATOR: P.S.C. Rao (904)392-1951 ABSTRACT: The project is designed to determine the ability of cosolvents to enhance the recovery of organic contaminants from waste disposal and spill sites by in situ solvent flushing. Computer models to describe the desorption, dissolution, and mobilization of organic chemicals from contaminated soils will be developed. Laboratory experiments will be conducted to obtain data for the evaluation of these models. The models will be used to assess the efficiency of in situ solvent flushing under various scenarios. A journal article will be prepared in June 1994. Microbial Metabolism of Munitions Wastes in Anoxic Aquifers INSTITUTE: Rice University (Guy Sewell, P.O.) TASK NO: 3071 PROJECT PERIOD: 05/94 - 04/97 PRINCIPAL INVESTIGATOR: Karen Petay (405) 325-4757 ABSTRACT: The objective of the investigation is to determine the metabolic fate of munitions wastes under defined anaerobic conditions. The project will result in a number of outputs including: • Journal Article on Pathways • Journal Article on Stimulation • Final Report on Microbial Metabolism of Munitions Wastes in Anoxic Aquifers 44 ------- Three-Dimensional NAPL Fate and Transport Model INSTITUTE; University of Texas (Jong Soo Cho, P.O.) TASK NO: 3075 PROJECT PERIOD: 10/93 09/96 PRINCIPAL INVESTIGATOR: Gary Pope (512) 471-3235 ABSTRACT: The objective of this project is to develop a three-dimensional model that describes subsurface contaminant transport and transformation in a ground-water aquifer with spatially and temporally varying conditions. The eventual use of the model will be as a planning and design tool for subsurface remediation projects. The model will incorporate physical, chemical, and microbiological processes that are known to occur in the real world but are not well accounted for in the current transport and fate models. A computer code with a user's manual will be developed and a workshop will be hosted for model users. Methods for Determining Multiphase Characteristic Curves for Use in Designing Subsurface Bioremediation Systems INSTITUTE: University of California at Davis (James Weaver, P.O.) TASK NO: 3077 PROJECT PERIOD: 10/93 09/96 PRINCIPAL INVESTIGATOR: Mark Grismer (916)752-3243 ABSTRACT: The objective of this project is to develop rapid methods for determining capillary pressure/saturation curves for multiphase subsurface systems. The data from these measurement techniques is needed as input data for models of fluid flow and contaminant transport for multiphase fluid systems, such as water, air, and nonaqueous-phase liquids. Development of Data Evaluation/Decision Support System for Bioremediation of Subsurface Contamination INSTITUTE: Massachusetts Institute of Technology (Mary Randolph, P.O.) TASK NO: 3078 PROJECT PERIOD: 10/93 09/96 PRINCIPAL INVESTIGATOR: Dennis McLaughlin (617)253-7176 ABSTRACT: The objective of this project is to develop computerized interpretation capabilities for both soft (qualitative) and hard (quantitative) field data of hydrogeologic environments. The computer aided conceptual model is to integrate knowledge of physical transport processes in terms of flow and transport model with statistical techniques and geologic formation processes. Output includes 3-D image of hydrogeologic environment, spatial and temporal distribution of contamination, and where to obtain samples to optimally refine the conceptual model. 45 ------- Development of Techniques for In Situ Bioremediation of Chromium Contaminated Soil and Groundwater: Phase I Laboratory Evaluation INSTITUTE: University of Oklahoma (Guy Sewell, P.O.) TASKNO: 3079 PROJECT PERIOD: 10/93 09/95 PRINCIPAL INVESTIGATOR: Michael Mclnerney (405) 325-4321 ABSTRACT: Design, evaluate and develop an in situ treatment technology for the use of microorganisms to reduce Cr (VI) to the more immobile and less toxic Cr (III). Chromium contamination of the subsurface is a common environmental problem associated with its use in many different industries and products including: electro-plating, tanning, fungicides, corrosion inhibitors, printing inks, and photographic films. In the subsurface, chromium occurs in either the oxidized Cr (VI) or reduced Cr (III) forms. The reduced form is relatively insoluble and has low toxicity, while the oxidized form, chromate (CrO42-), is highly soluble, mobile and carcinogenic. Conventional pump-and-treat technologies utilized to remediate chromium contaminated subsurface sites have limitations in terms of time, cost and effectiveness. Recently it has been recognized that some micro-organisms can utilize oxidized metal species [including Cr (VI)] as terminal electron acceptors for anaerobic respiration. Microbial based treatment technologies for the degradation of organic wastes have shown great promise as a method for dealing with these compounds in situ. While metals cannot be degraded by microorganisms, it is possible that the ability of microorganisms to alter the oxidation states of metals could be useful in controlling the mobility and relative toxicity of contaminant metals in the subsurface, thereby mitigating their potential human health and ecological hazard. Further information on microbial oxidation/reduction processes is needed before efficient treatment technologies can be designed. Outputs of the project will include a Biosystems Presentation and a Final Report. Bioremediation of BTEX, Naphthalene, and Phenanthrene in Aquifer Material Using Mixed Oxygen/Nitrate Electron Acceptor Conditions INSTITUTE Johns Hopkins University (Steve Hutchins, P.O.) TASKNO: 3081 PROJECT PERIOD: 10/93 09/96 PRINCIPAL INVESTIGATOR: Edward Bouwer (410) 516-8668 ABSTRACT: The objective of this research is to develop a better understanding of the effect of oxygen alone, nitrate alone or a combination of oxygen and nitrate on the biodegradation of certain mono- and polycyclic aromatic hydrocarbons in contaminated aquifer materials. Specifically, the proposed research will include batch studies to assess stoichiometry and kinetics of biodegradation of target compounds under strict aerobic, strict denitrifying and mixtures of oxygen and nitrate, column studies to simulate single continuous flow injection well, multiple injection wells and pulsed or intermittent injection schemes under mixed electron acceptor conditions. Outputs will include a Final Report on Bioremediation of BTEX, Naphthalene, and Phenanthrene in Aquifer Material Using Mixed Oxygen/Nitrate Electron Acceptor Conditions. 46 ------- Bioremediation of Fuel-Contaminated Aquifers Using Mixed Electron Acceptor Conditions INSTITUTE: University of Waterloo (Steve Hutchins, P.O.) TASK NO: 3082 PROJECT PERIOD: 10/93 09/96 PRINCIPAL INVESTIGATOR: J.F. Barker (519)885-1211x2103 ABSTRACT: This task will establish the role of nitrate as an electron acceptor for anaerobic biotransformation of BTEX compounds, and to investigate whether any advantage can be expected under mixed conditions where both nitrate and oxygen are provided. The specific objective is to evaluate the potential for degradation of benzene under conditions where both nitrate and oxygen are available. A final report will be prepared. Evaluation of In-Situ Bioremediation of Chlorinated Hydrocarbon Contaminated GW at Air Force Plant 44 INSTITUTE: Western Region Hazardous Substance Research Center Center, Stanford University (Scott Ruling, P.O.) TASK NO: 3085 PROJECT PERIOD: 09/93 09/95 PRINCIPAL INVESTIGATOR: Perry McCarty (415)723-4131 ABSTRACT: The USAF/CEVR is funding the U.S. EPA, RSKERL, Ada, OK, to develop a two-year project with EPA's Western Region Hazardous Waste Research Center (Stanford and Oregon State Universities) to evaluate the efficacy and efficiency of an in-situ bioremediation process for contaminated ground water at Air Force Plant 44. Activities will relate to treatability studies at Stanford University and Moffett Field, California, and full-scale design, operation, and evaluation at Plant 44 in Tucson, Arizona. A report will be prepared on the evaluation of in-situ bioremediation of chlorinated hydrocarbon contaminated ground water at Air Force Plant 44. 47 ------- H202 and Microbial System Interactions INSTITUTE: RSKERL/ManTech (Roger Cosby, P.O.) TASK NO: 3086 PROJECT PERIOD: 09/93 12/95 PRINCIPAL INVESTIGATOR: Scott Ruling (405) 436-8610 ABSTRACT: The objective is to quantify the oxidative potential of H202 decomposition during enzymatic and nonenzymatic catalyzed reactions and to evaluate H202 persistence in different chemical and biological solutions. The experimental data will greatly improve the conceptual model of the oxidative effects of H202 in microbially active aquifer material. This will help develop the theoretical and experimental framework for understanding and quantifying the effects of H202 on parameters influencing microbial mobility, i.e., microbial and collector surfaces, and ultimately, microbial mobility and activity in subsurface environments. Additionally, this will also help quantify the effects of microbial populations in engineered oxidation systems and to evaluate the effects of H202 on microbial toxicity. An Internal Report on H202 and Microbial System Interactions will be prepared. A Pilot-Scale Demonstration of Surfactant-Enhanced Subsurface Remediation of Chlorinated Hydrocarbons INSTITUTE: University of Oklahoma (Candida West, P.O.) TASK NO: 3087 PROJECT PERIOD: 03/94 - 02/95 PRINCIPAL INVESTIGATOR: Robert Knox (405)325-5911 ABSTRACT: A small-scale field study of surfactant-enhanced contaminant removal using a recirculating well system will be conducted at the US Coast Guard Station in Traverse City, Michigan. The choice of surfactant system to be used will be based on laboratory research conducted under Task 3035. A Report on Small-Scale Field Evaluation of Surfactant-Enhanced Contaminant Removal will be written as the output for this project. 48 ------- China-US Soils & Ground Water Remediation Research INSTITUTE: Sino-US International Agreement (Bert Bledsoe, P.O.) TASK NO: 4025 PROJECT PERIOD: Continuing PRINCIPAL INVESTIGATOR: ABSTRACT: Strengthen scientific ties with the People's Republic of China (PRC) by conducting a cooperative research program to study the remediation of an aquifer contaminated with diesel fuel, soil contaminated with heavy oil, and their eventual impact on the beneficial use of the ground water. Outputs for this project include: • Internal Report on Soils Remediation • Internal Report on Aquifer Remediation • Article on Soils & Aquifer Remediation Treatment of Process Off-Gases Contaminated with TCE Using Ex-Situ Soil Based Aerobic Bioreactors INSTITUTE: U.S.G.S. (John Wilson, P.O.) TASK NO. 5001 PROJECT PERIOD: 04/94 09/94 PRINCIPAL INVESTIGATOR: Theodore Ehlke (609)771-3924 ABSTRACT: This effort will develop information on the kinetics of biological TCE co-oxidation supported by JP-4, Stoddard Solvent, Technical Grade Toluene, and Phenol. An open-file USGS report will be written. Evaluation of Passive Remediation Techniques at Mixed-Waste Sites Using Geochemical Barriers INSTITUTE: Cooperative Agreement TASK NO: 0935-001 PROJECT PERIOD: Proposed PRINCIPAL INVESTIGATOR: ABSTRACT: The objective of this project is to evaluate the effectiveness of passive geochemical barriers for mixed waste composed of chlorinated solvents and chromium. The project will be conducted at field scale at a well-characterized waste site. The project will be closely interlinked with ongoing and planned laboratory research to elucidate and understand the mechanisms at work in the field setting. A Report on the Evaluation of Passive Geochemical Barriers for Mixed Waste Sites will be prepared. 49 ------- Design Manuals for the Extraction of Contaminants from Unconsolidated Subsurface Environments INSTITUTE: Cooperative Agreement TASK NO: 0935-002 PROJECT PERIOD: Proposed PRINCIPAL INVESTIGATOR: ABSTRACT: The objective of this project is to do a side-by-side comparison of several enhanced extraction techniques for remediating sites with residual NAPL contamination. Techniques to be evaluated will include the addition of surfactants, the addition of cosolvents, and the addition of thermal energy. This will be a pilot-scale field study with supporting laboratory work. The various techniques will be compared using side-by-side cells made of sheet piling. The project will be conducted at two or more sites to determine the effect of hydrogeologic setting on the effectiveness of the remediation technology. A Design Manual for Extraction of Contaminants from Unconsolidated Subsurface Environments will be developed. Evaluation of Pulsed Pumping for Improving the Efficiency of Pump-and-Treat Remedial Actions INSTITUTE: US Air Force TASK NO: 0935-003 PROJECT PERIOD: Proposed PRINCIPAL INVESTIGATOR: ABSTRACT: The objective of this project is to evaluate the improvement in efficiency that can be achieved for pump-and- treat remedial actions through the use of pulsed pumping. The project will be a pilot-scale field study that will compare a variety of pumping schemes. A Report on the Evaluation of Pulsed Pumping for Improving the Effectiveness of Pump-and- Treat Remedial Actions will be written. Evaluation of Cosolvent Flushing for Increasing Mobility of NAPLs INSTITUTE Cooperative Agreement TASK NO: 0935-004 PROJECT PERIOD: Proposed PRINCIPAL INVESTIGATOR: ABSTRACT: The objective of this project is to evaluate the feasibility of using miscible cosolvents to increase the mobility of residual NAPLS in subsurface environments. The project will be conducted as a pilot-scale field study using small sheet-piling cells to provide hydraulic containment. 50 ------- Transformation and Transport Processes of Hydrocarbon Vapors in the Vadose Zone INSTITUTE: RSKERL TASK NO: 0935-RSFB3 PROJECT PERIOD: 10/93 PRINCIPAL INVESTIGATOR: Frank Beck (405) 436-8546 ABSTRACT: The objective of this project is to identify the volume of hydrocarbon vapors being transported to the soil surface by plants. The large lysimeters at the RSKERL field site will be used to examine emissions from plants growing above contaminated soil to monitor emission enhancement by plants. A journal article will result from this project. Oxygen Consumption in Clay Soils Contaminated by #2 Fuel Oil INSTITUTE: RSKERL TASK NO: 0935-EADG2 PROJECT PERIOD: 03/94 03/95 PRINCIPAL INVESTIGATOR: Dominic DiGiulio (405) 436-8607 ABSTRACT: The objective of this project is to determine the feasibility of introducing air into silty clay soils contaminated by #2 fuel oil, and to determine the correlation of oxygen consumption rates with in-situ petroleum hydrocarbon degradation rates using a reference alkane. This project will be carried out in the field with supporting laboratory measurements. Chemically Enhanced Dissolution and Mobilization of Residual Contaminants INSTITUTE- RSKERL TASK NO: 0935-RSLW3 PROJECT PERIOD: 10/93 12/96 PRINCIPAL INVESTIGATOR: Lynn Wood (405)436-8552 ABSTRACT: The objective of this project is to assess the ability of organic cosolvents to enhance the removal of residual- phase organic contaminants by in-situ soil flushing. Soil columns containing residual NAPLs will be eluted with mixtures of water and organic cosolvents. The rates and extent of NAPL dissolution and mobilization will be assessed under differing experimental conditions. Successful laboratory results will be evaluated in the field in cooperation with the University of Florida under Task 1086. Outputs for the project include a Journal article and a Research Brief or Issue Paper on Solvent Flushing for Subsurface Remediation. 51 ------- Remediation of Chromium Contaminated Soils and Ground Water at a Chrome Plating Site / INSTITUTE: RSKERL TASK NO: 2072 PROJECT PERIOD: 06/92 - 09/95 PRINCIPAL INVESTIGATOR: Robert Puls (405) 436-8543 ABSTRACT: The objective of this project is to use a chrome plating site at Elizabeth City, North Carolina to develop and test innovative remediation techniques for metal-contaminated waste sites. The project will include laboratory and field testing of soil washing, in-situ mobilization, and ground water sampling techniques. Project outputs will include a Journal article and an EPA Issue Paper on Remediation of Chrome Plating Waste Sites. Sorption of Polar Organic Compounds to Colloidal Particles INSTITUTE: RSKERL TASK NO: 0940-RSSM3 PROJECT PERIOD: 08/92 11/94 PRINCIPAL INVESTIGATOR: Susan Mravik (405) 436-8553 ABSTRACT: The objective of this project is to investigate the relationship between the characteristics of polar, ionizable organic compounds and their sorption to particles with different properties such as clay mineralogy, surface charge, and organic carbon content. The approach will be to select compounds for study that will cover a range of pKa and log Kow values. Sorbents that will provide a range in clay mineralogy and organic carbon content will be selected. The project will be initiated with batch studies at various values of pH. The results of the batch studies will be used to plan column studies to investigate transport of the ionic compounds. Pore-Scale Investigation of the Behavior of Remedial Fluids INSTITUTE: Cooperative Agreement TASK NO: 0946-001 PROJECT PERIOD: Proposed PRINCIPAL INVESTIGATOR: ABSTRACT: Laboratory and numerical investigations will be carried out concerning the behavior of pore-scale phenomena that are expected to influence the successful application of chemical additives for the removal of nonaqueous-phase liquids. A Report on the Pore-Scale Behavior of Remedial Fluids will be developed. 52 ------- Changes in Subsurface Wetting Behavior in the Presence of NAPLs INSTITUTE: RSKERL/ManTech TASK NO: 0946-002 PROJECT PERIOD: Proposed PRINCIPAL INVESTIGATOR: ABSTRACT: The wetting properties of aquifer materials are one of the important factors controlling the migration of NAPLs and the likelihood of successful removal. Although these materials are normally water wet, there is evidence that they may become oil wet under long-term exposure to NAPLs. This project will collect laboratory data to measure the extent of these changes in wetting behavior and the conditions under which it occurs. The output for this project will be a Report on Changes in Subsurface Wetting Behavior in the Presence of NAPLs. Abiotic Reduction of Chrome from Zero-Valence Iron Dissolution INSTITUTE: RSKERL/ManTech TASK NO: 0946-004 PROJECT PERIOD: Proposed PRINCIPAL INVESTIGATOR: ABSTRACT: The objective of this project is to develop data on the mechanisms of chrome reduction kinetics in the presence of elemental iron, the kinetics of the electrolytic reduction process, the effect of sulfate and other anionic species on both processes, the effect of soil mineralogy, and the potential for reactivating the iron surface following the development of an oxidized coating. The work will be carried out in laboratory-scale stirred batch reactors to evaluate the effects of variations of critical parameters. The results of these laboratory studies will be used to plan possible field evaluation of this methodology for remediation of sites with chromium contamination. 53 ------- Evaluation of Proposed Closure Criteria at Remediated Sites INSTITUTE: Cooperative Agreement TASK NO: 0948-001 PROJECT PERIOD: Proposed PRINCIPAL INVESTIGATOR: ABSTRACT: The objective of this project is to evaluate different approaches that have been proposed for establishing scientifically soil cleanup levels or closure criteria for hazardous waste sites. This effort will use a combination of laboratory work and evaluation of the approaches by an expert panel. The output from this task will be a report delineating the suitability of various screening tools for specific applications including site specific methodologies that would require a more detailed analysis of the hydrogeologic system. The project will result in a Report on the Evaluation of Proposed Soil Screening Level Criteria. Natural Attenuation of Ground Water Contaminants at Air Force Installations INSTITUTE: RSKERL (US Air Force) TASK NO: 0949-001 PROJECT PERIOD: 06/93 - 09/94 PRINCIPAL INVESTIGATOR: John Wilson (405) 436-8532 ABSTRACT: The bioremediation research team of RSKERL has developed a provisional strategy to evaluate the rate and extent of natural attenuation of organic contaminants in ground water. Under this IAG, the bioremediation research team will apply the provisional strategy to two plumes located on U.S. Air Force Installations. Samples will be taken at locations extending from the source of each plume, along the midline to the periphery of each plume. Soil and ground-water samples from the plumes will be analyzed for the concentrations of contaminants, nutrients, and electron acceptors. This information will be input to the BIOPLUME II model, which will be used to estimate attenuation. The project will produce a Draft Guidance on Assessing Natural Attenuation of Ground Water Contaminants at Air Force Installations. 54 ------- Denitrification for Bioremediatiun of a Refinery Spill - Park City, Kansas INSTITUTE: RSKERL TASK NO: 3031 PROJECT PERIOD: 02/92 08/94 PRINCIPAL INVESTIGATOR: John Wilson (405) 436-8532 ABSTRACT: The objective is to evaluate the relative efficacy of (1) BTEX fermentation, (2) BTEX denitrification, and (3) BTEX denitrification supplemented with oxygen for remediation of subsurface contamination with refined petroleum hydrocarbons. A spill from a refinery pipeline in Park City, Kansas will be subdivided into six plots of about an acre each. One plot will recirculate ground water amended with ammonium chloride to stimulate fermentation of BTEX compounds. A second plot will recirculate ammonium chloride and sodium nitrate, and a third plot will recirculate ammonium chloride, sodium nitrate, and oxygen. This task will provide the following output. • A journal article describing the success of nitrate for bioremediation of a fuel spill in a full-scale remediation Bioventing to Remediate a JP-4 Spill at the USCG Site at Elizabeth City, North Carolina INSTITUTE: RSKERL TASK NO: 3064 PROJECT PERIOD: 06/92 09/93 PRINCIPAL INVESTIGATOR: John Wilson (405) 435-8532 ABSTRACT: Air Sparging and Air Injection are new techniques for in situ bioremediation. They are finding wide application, but there is little documentation of their performance at field scale. This project will carry out Air Injection at a JP-4 spill site. We will document the performance of Air Injection with respect to reduction in contaminant mass in ground water and soil. A Journal Article Describing the Efficacy of Air Injection for Treatment of Subsurface Fuel Spills will be developed. 55 ------- Feasibility Study on Enhancement of Nitrate-Based Bioremediation Using Surfactants INSTITUTE: RSKERL TASK NO: 0949-RPBW1 PROJECT PERIOD: 10/93 09/94 PRINCIPAL INVESTIGATOR: Barbara Wilson (405) 436-8993 ABSTRACT: Conduct laboratory studies of biorestoration supported by denitrification aided by use of surfactants. A series of experiments will be conducted to determine whether denitrification using nitrate can be significantly enhanced by increasing bioavailability of fuel components through the process of micellization. This process would be unique in that the surfactant chosen would be nonbiodegradable under denitrifying conditions (anaerobic), but would be readily degraded under aerobic conditions, and in fact, aid in the final "polishing11 step, the aerobic biodegradation of any residual contaminant components. Studies will be conducted using contaminated aquifer materials collected from field sties. The results of these studies will be evaluated to determine if further studies are warranted. The investigation will result in the following outputs: • ACS Presentation • Journal Article Vinyl Chloride/TCE at St. Joseph, MI Site INSTITUTE: RSKERL TASK NO: 0949-RPDK4 PROJECT PERIOD: 09/93 08/94 PRINCIPAL INVESTIGATOR: Don Kampbell (405) 436-8564 ABSTRACT: The project is designed to determine amount of TCE plume entering nearby Lake Michigan. A final report on on Vinyl Chloride/TCE at St. Joseph, MI Site will be prepared. Aerobic Co-Oxidation of TCE Vapors INSTITUTE: RSKERL TASK NO: 0949-RPDK3 PROJECT PERIOD: 01/90 12/95 PRINCIPAL INVESTIGATOR: Don Kampbell (405) 436-8564 ABSTRACT: Demonstrate enhanced cometabolic degradation of TCE and other chlorinated analogs in the presence of petroleum hydrocarbon microbial utilizers. A Journal Article on Aerobic Co-Oxidation of TCE Vapors will be published. 56 ------- Reductive Anaerobic Biological In-Situ Treatment INSTITUTE: RSKERL TASK NO: 0949-RPGS3 PROJECT PERIOD: 01/93 12/96 PRINCIPAL INVESTIGATOR: Guy Sewell (405) 436-8566 ABSTRACT: Design and field test (pilot scale) reductive anaerobic bioremediation. To date bioremediation technologies have focused on the use of bacteria to oxidize organic contaminants under both aerobic and anaerobic conditions. The organisms may utilize the contaminant as a metabolizable carbon source or nutrient, or be induced to co-metabolize it in the presence of the proper inducer. Biotransformation also can occur where the targeted contaminant serves as terminal electron acceptor and is thereby reduced. Many contaminants which are recalcitrant to bio-oxidative attack have been shown to undergo reductive biotransformations. These reductive biotransformations can lead to detoxification, mineralization and/or mobility alterations of the target compounds. Two model compounds have been identified for possible targets of reductive anaerobic bioremedial in-situ technologies (RABIT); chromate (CR VI) and tetrachloroethene (PCE). The investigation will result in the development of a Treatment Design and Operational Protocol. Petroleum Hydrocarbon Biodegradation Under Mixed Denitrifying/Microaerophilic Conditions INSTITUTE: RSKERL TASK NO: 0949-RPDM3 PROJECT PERIOD: 03/93 10/94 PRINCIPAL INVESTIGATOR: Dennis Miller (405) 436-8567 ABSTRACT: To conduct laboratory treatability studies of biorestoration supported by mixed denitrifying/microaerophilic conditions for clean-up of a fuel spill in a selected aquifer. A Journal Article on Use of Low Oxygen Levels to Enhance Nitrate-Based Bioremediation will be published. Prepared Bed Bioremediation in Buried Lifts as Affected by Oz Concentrations in Soil Gas INSTITUTE: Utah State University (Scott Ruling, P.O.) TASK NO: 0949-003 PROJECT PERIOD: 09/93 - 03/96 PRINCIPAL INVESTIGATOR: Ron Sims (801) 750-2926 ABSTRACT: The project is designed to determine whether contaminants in buried lifts in land treatment units continue to degrade with time. A project report will be developed at the end of the investigation. 57 ------- Biological Treatment of Trichloroethylene Contaminated Process Off-Gas INSTITUTE; U.S. Army Corps of Engineers Waterways Experiment Station (John Wilson, P.O.) TASK NO: 0949-004 PROJECT PERIOD: 04/94 - 09/94 PRINCIPAL INVESTIGATOR: Mark Zappi/Capt. R. Morgan (601)634-2856 ABSTRACT: This investigation is designed to evaluate a variety of candidate column packings for support of key microbial consortia for treatment of a TCE contaminated gas stream. A final report will be prepared. 58 ------- UNDERGROUND INJECTION CONTROL Research in support of the Underground Injection Control Program is directed at developing methods to assure the mechanical integrity of the injection well itself, and that wastes remain in the zone of injection. Research is also aimed at determining the fate of wastes that enter the injection zone. Injection Well Mechanical Integrity INSTITUTE East Central University (Jerry Thomhill, P.O.) TASK NO: 1060 PROJECT PERIOD: 10/91 09/94 PRINCIPAL INVESTIGATOR: Bob Benefield (405) 332-8000 ABSTRACT: The objectives of this project are to test methods for determining internal (no significant leaks in casing, tubing, and packer) and external (no significant fluid movement through vertical channels adjacent to the injection well bore) mechanical integrity of injection wells to assure that the use of such wells will not endanger underground sources of drinking water, public health, or the environment. The approach to the project is to evaluate various production logging techniques to track fluid movement within and behind pipe, and through leaks to zones other than the designated injection zones. Specific well conditions will be simulated in a series of research wells. Tools and techniques will be evaluated to determine how they work, what they measure, and how these measurements are related to flow. At the end of the project a Report will be prepared discussing the Tests for Flow Behind Pipe. Potential for Invasion of Underground Sources of Drinking Water Through Mud-Plugged Wells: An Experimental Appraisal INSTITUTE: Oklahoma State University (Don Draper, P.O.) TASK NO: 1065 PROJECT PERIOD: 10/91 -09/94 PRINCIPAL INVESTIGATOR: Marvin Smith (405)744-5711 ABSTRACT: The objective of the project is to determine whether a predictable relationship exists between the standard measured properties of drilling mud, the in-situ well plugging fluid, the adjacent reservoir permeability, and the differential pressure which causes invasion of reservoirs. In order to accomplish these objectives two systems and five subsystems are to be designed and constructed. Pre-test procedures will be required for cores and fluids. Tests to be performed will be well system simulation, mudcake, effective permeability, and mud setting. A final report of the findings will be prepared. 59 ------- WELLHEAD PROTECTION The 1986 Amendments to the Safe Drinking Water Act require the delineation of protection areas around public water wells to protect water systems. RSKERL is conducting research to advance the fundamental scientific knowledge of subsurface processes, develop new wellhead protection methods, and provide technical assistance on basic scientific and engineering wellhead protection issues. The audiences for research results are EPA's Regional Offices, state and local officials, and public water suppliers. Hydrogeologic Mapping to Delineate Wellhead Protection Zones Around Springs INSTITUTE: State of Utah (Steve Acree, P.O.) TASK NO: 1052 PROJECT PERIOD: 10/90 02/93 PRINCIPAL INVESTIGATOR: Mark Jensen (801)531-6459 ABSTRACT: The project is designed to develop and field test an applicable hydrogeologic mapping method to delineate wellhead protection zones around springs. The use of hydrogeologic mapping techniques will be used to determine the zone of contribution to two springs in differing hydrogeologic settings, then verify the zone of contribution with chemical analyses and hydrologic studies. A Final Report titled "Methods for Delineating Wellhead Protection Zones Around Springs" will be prepared. The Development of a Risk Management Strategy for Wellhead Protection INSTITUTE: University of Miami (David Burden, P.O.) TASK NO: 1054 PROJECT PERIOD: 09/91 08/93 PRINCIPAL INVESTIGATOR: David Chin (305) 284-3391 ABSTRACT: The principal objective of the project will be to develop a risk-management strategy for wellhead protection that can be directly utilized in formulating land use controls within a protection area. Using the risk management strategy, contaminant source fluxes and attenuation characteristics are taken as random variables, and the probability distribution of the resulting contaminant concentration in the pumped water is then estimated. By defining maximum allowable contaminant levels at the wellhead, the risk of exceeding these allowable levels for given land uses may be calculated. As a consequence to defining an acceptable level of risk, land use controls may then be implemented within the protection area based on a clearly defined quantitative measure. A Final Report titled "Development of a Risk-Management Strategy for Wellhead Protection" will be prepared. 60 ------- Determination of Subsurface Assimilative Capacity INSTITUTE- RSKERL TASK NO: 1057 PROJECT PERIOD: 01/91 12/94 PRINCIPAL INVESTIGATOR: Michael Jawson (405) 436-8560 ABSTRACT: This project is designed to develop a method for delineating wellhead protection areas based on the use of the assimilative capacity criterion which; (a) can be applied by the majority of the states, (b) is scientifically defensible, and (c) can be used to address significant contamination threats to public water supply wells. The initial tasks are the identification and classification of contaminants that currently present the greatest health threat to public ground-water supplies, and to evaluate the processes which contribute to the assimilative capacity in order to develop integrated assimilative capacity precepts. Eventually, a model incorporating assimilative capacity into the delineation of wellhead protection zones will be developed either by modifying an existing model or through the development of a new model. An Interim Report for the Application of Assimilative Capacity Criteria to Wellhead Protection Delineation Methods will be prepared as well as a Report on Contaminant Identification and Classification. Delineation of Wellhead Protection Zones: Consideration of Virus Transport INSTITUTE: University of Arizona (Guy Sewell, P.O.) TASK NO: 1058 PROJECT PERIOD: 10/91 05/94 PRINCIPAL INVESTIGATOR: Charles Gerba (602)621-6906 ABSTRACT: The objective of the study is to enable EPA to delineate wellhead protection zones with respect to source areas contributing bacteria and viruses into ground water. The approach will be to examine the effects of changes in pH, ionic strength, and water content on the retention and release of sorbed viruses. The Final Report will discuss the Delineation of Wellhead Protection Zones with Respect to Virus Transport. 61 ------- Demonstration of the Analytical Element Method for Wellhead Protection INSTITUTE: Indiana University (Stephen Kraemer, P.O.) TASK NO: 1059 PROJECT PERIOD: 06/91 12/93 PRINCIPAL INVESTIGATOR: Henk Haitjema (812)855-0731 ABSTRACT: The purpose of the project is to demonstrate and adopt the new solution technique known as the Analytical Element Method for application in wellhead protection. The objective will be accomplished by developing a public domain model with manual and user's guide supporting EPA personnel in developing proficiency with the technique, and demonstrating the applicability of the technique at a field site to be selected in consultation with EPA staff. The following outputs will result from this investigation: • Prototype versions of programs released for testing. • Beta version with on screen editor and draft manuals. • Final version of programs. • Final Report of the Demonstration of the Analytical Element Method for Wellhead Protection. Capture Zone Delineation: Models and Experiments INSTITUTE: New Mexico Institute of Mining and Technology (Stephen Kraemer, P.O.) TASK NO: 1062 PROJECT PERIOD: 07/91 01/94 PRINCIPAL INVESTIGATOR: John L. Wilson (505) 835-5308 ABSTRACT: A series of field experiments and computer modeling simulations will be applied at the Borden Site in Ontario, Canada. The objectives include: (1) the validation or invalidation of existing capture zone delineation methods, (2) an improvement in understanding the behavior and nature of capture zones in real aquifers, and (3) the investigation of new and improved concepts and methods for delineation. The field experiments will involve detailed head measurements and observations of tracer breakthrough curves during pumping at a well. The experimental design will be assisted by the use of existing computer programs. The observed time-of-travel delineated capture zones will be compared to the predicted zones in order to contribute a level of validation of existing modeling techniques. Improvement of existing models will be suggested by the field results. A Final Report on the Validation of Models for Delineating Capture Zones in Wellhead Protection will be prepared at the end of the project. 62 ------- Capture Zone Delineation Using the EPA WHPA Model and Other Codes: A Comparative Study in Ellis County, Kansas. INSTITUTE: RSKERL TASK NO: 1063 PROJECT PERIOD: 09/90 09/92 PRINCIPAL INVESTIGATOR: David Burden (405) 436-8606 ABSTRACT: The objective of this project was initially to assist the City of Hays, Kansas, in the establishment of a Wellhead Protection Program. Since the initial meeting with the Ellis County Water Wellhead Protection Committee, RSKERL has been providing assistance in the form of actual computer modeling of the wellfield. The purpose is to conduct in-house research on the effectiveness of EPA's WHPA Model and compare the results with other popular delineation codes being used in wellhead protection. The approach will initially consist of using EPA's WHPA Model Version 1.0 to delineate capture zones. This will be followed by using the Version 2.0 of the WHPA Model and comparing the results of both WHPA models with other computer codes used to delineate capture zones. The final phase of the project will involve incorporating the results of the capture zones into a Geographic Information System. The Final Report will be an Evaluation of the Wellhead Protection Area Delineation Methods, including the use of the WHPA Code at Hays, Kansas. Technical Assistance and Technology Transfer in Wellhead Protection INSTITUTE: RSKERL TASK NO: 1064 PROJECT PERIOD: Continuing PRINCIPAL INVESTIGATOR: David Burden (405) 436-8606 ABSTRACT: The objective of this project is to provide technical assistance and technology transfer to communities, towns, and cities desiring to know and learn more about establishing a wellhead protection program in their area. The basic approach includes conducting seminars and making presentations about the EPA Wellhead Protection Program. Presentations typically consist of explaining the basic idea of a wellhead protection program, discussing RSKERL's current research activities in this area, and if requested, providing software demonstrations of EPA's WHPA Model. 63 ------- Contaminant Identification and Classification INSTITUTE University of Oklahoma (Michael Jawson, P.O.) TASK NO: 1066 PROJECT PERIOD: 09/91 12/92 PRINCIPAL INVESTIGATOR: Larry Canter (405) 325-5202 ABSTRACT: The primary objectives of this project are to identify and prioritize those contaminants and their associated sources which present the greatest health threat in public ground-water supplies. Five tasks will be undertaken. The initial task involves specific decision making and detailed planning to be done in conjunction with EPA Headquarters. Task two involves the documentation of problems experienced with public ground-water supplies including the identification of contaminants and their sources as well as potential future contaminants. The third Task consists of the development of a classification system. Task four will highlight case studies selected from the survey of Task two and will be used to illustrate those findings and the applicability of the classification system. The final Task will be to prepare the summary report. The first output of the project will be the Identification and Classification Report. This will be followed by a report of findings of the Survey of Major Contaminants Impacting Public Drinking Water Wells. Ground-Water Flow in a Carbonate Aquifer, Southern Oklahoma INSTITUTE: USGS (Stephen Kraemer, P.O.) TASK NO: 1074 PROJECT PERIOD: 03/93 02/94 PRINCIPAL INVESTIGATOR: Ronald Hanson (405)231-4256 ABSTRACT: The overall objective of this study is to develop, improve, and test methods to quantify and describe deeply circulating ground-water flow in carbonate aquifers. The tools and technologies will be used to characterize the Simpson Arbuckle Aquifer in south-central Oklahoma. Activities include: database construction; borehole logging of a single open hole; design packer hydraulic tests and a geochemical sampling; and sampling three wells for carbon, hydrogen isotopes, dissolved cations and anions to assist in age dating the water. Reports will be prepared describing the results of the investigation. 64 ------- System Analysis for Evaluating Aquifer Assimilative Capacity INSTITUTE Rice University Consortium (David Burden, P.O.) TASK NO: 1075 PROJECT PERIOD: 10/92 09/94 PRINCIPAL INVESTIGATOR: Herb Ward (713) 527-4086 Phil Bedient (713) 527-4953 ABSTRACT: The result of this research will be a highly organized system of models and databases which will be applied to a demonstration aquifer for defining and calculating assimilative capacity under a variety of assumptions. Aquifer data will be mapped using a GIS and models will be applied from the surface through the unsaturated and saturated zones to the nearest major water supply well having a wellhead protection zone. Dilution, sorption, and biodegradation of a variety of organic contaminants will be carefully evaluated, as they relate to transport and fate mechanisms in the subsurface. As a result, the project will combine both computational and experimental approaches to evaluating aquifer and subsurface assimilative capacity. Ground-water flow and transport models, aquifer databases from fate and transport research, and decision support tools will be integrated in a systems analysis approach of aquifer assimilative capacity. Activity will center on a specific aquifer selected on the basis of available data, appropriateness of descriptive models, and use. Economic Value of Ground Water INSTITUTE: National Research Council (James McNabb, P.O.) TASK NO: 1081 PROJECT PERIOD: PRINCIPAL INVESTIGATOR: ABSTRACT: The objective of this effort is to evaluate approaches for assessing the long-term economic value of ground water and the economic impacts if ground water is contaminated or depleted. The study will be carried out by the National Academy of Sciences/National Research Council over a period of two-years. The NRC will appoint a committee of experts to (1) review and critique various approaches for estimating the future value of the subsurface and uncontaminated ground water; (2) delineate preferred approaches; (3) outline what needs to be done to implement the recommended approaches; and (4) illustrate through examples how recommended procedures would be applied in practice for representative applications. The investigation will result in a NAS/NRC Report on Assessing the Future Value of Ground Water 65 ------- Risk Management Decision Support System (RMDSS) for Wellhead Protection INSTITUTE: RSKERL TASK NO: 1082 PROJECT PERIOD: PRINCIPAL INVESTIGATOR: David Burden (405) 436-8606 ABSTRACT: The objective of this project is to build a decision support system for calculating the risk to ground water caused by numerous types of human activities. The system will correlate commercial/residential activities and land use with the probability of a deleterious effect at the wellhead. The probability of occurrence of an accident within the zone of contribution will be incorporated into existing codes that estimate the risk that the ground water at the wellhead will be contaminated and the path and arrival time of that contaminant at the wellhead. A Risk Management Decision Support System (RMDSS) for Wellhead Protection will be produced by the project. 66 ------- MATHEMATICAL MODELING RSKERL scientists are developing and testing a variety of mathematical models that describe and predict contaminant transport in porous and fractured media under a variety of conditions from biodegradation to immiscible flow. From planning and evaluating remediation scenarios, to identifying wellhead protection areas and permitting injection wells, mathematical modeling is becoming an increasingly important tool in Agency decision making. Multiphase Flow in Soils: Modeling and Experimental Study INSTITUTE; University of Colorado (James Weaver, P.O.) TASK NO: 2036 PROJECT PERIOD: 07/90 05/92 PRINCIPAL INVESTIGATOR: Tissa Illangasekare (303) 492-6644 ABSTRACT: The purpose of this project is to make detailed laboratory measurements of the distribution of water, an oily phase, and air during and after simulated spills and rainfall events. The purpose is also to measure the necessary model parameters so that experiments can be used to test simple models developed at CU and RSKERL. The existing dual-gamma system at UC-Boulder will be used to determine fluid distributions in laboratory columns after intermittent applications of the oily phase and water. Several scenarios, which correspond to assumptions in the models to be tested, will be simulated. Saturated conductivities and capillary pressures will be measured using a flow-pump technique in order to determine the basic data needed by the models. Experiments will also be run in a two-dimensional tank to evaluate the usage of one- dimensional models. A final report will be prepared on Laboratory and Modeling Studies of Multiphase Flow. Three-Dimensional Modeling of Subsurface Flow, and Fate and Transport of Microbes and Chemicals INSTITUTE: Penn State University (Thomas Short, P.O.) TASK NO: 2055 PROJECT PERIOD: 10/91 12/94 PRINCIPAL INVESTIGATOR: George Yeh (814) 863-2931 ABSTRACT: The objectives of this project are to develop a three-dimensional numerical algorithm for the solution of the saturated-unsaturated transport equations for multiple components that undergo mutual reactions based on the LEZOOM approach and to analyze test data produced from physical model aquifers at RSKERL. A mathematical code will be developed which is capable of simulating experimental runs on RSKERL physical model aquifers. The results produced by the code will be compared with experimental data to determine if the proposed mathematical description of the mechanisms involved is adequate. A report with the same title as the project will be prepared. 67 ------- Validation of the Approximate Multiphase Flow Models INSTITUTE: RSKERL TASK NO: 2059 PROJECT PERIOD: 09/91 09/93 PRINCIPAL INVESTIGATOR: James Weaver (405) 364-8545 ABSTRACT: The object of the project is to test the KOPT (Kinematic Oily Pollutant Transport) portion of the HSSM (Hydrocarbon Spill Simulation Model) by comparison with laboratory data. Several oils will be released into specially designed columns which are packed with various porous media. The ponding depth and depth of the oil front will be recorded as functions of time. Independent measurements of the model parameters will be made on the column. The average values of the parameters will be used as KOPT model input data. The model results will be compared with the laboratory data experiments. Monte Carlo simulation will be used to assess the impact of uncertainty in the values of the parameters. Three-Dimensional Multiphase Flow and Contaminant Transport Mathematical Model INSTITUTE: University of Vermont (Thomas Short, P.O.) TASK NO: 2076 PROJECT PERIOD: 10/92 10/95 PRINCIPAL INVESTIGATOR: George Finder (802) 656-3390 ABSTRACT: The objective of this project is to develop mathematical modeling of the processes involved in the movement of mixtures of nonaqueous phase liquids through the vadose zone into the aquifer. The model will include the presencs of a vapor phase, solid phase, and the nonaqueous phase. The model will be three-dimensional and be applicable to both dense nonaqueous phase liquids (DNAPLs) and light nonaqueous phase liquids (LNAPLs). This model will be used to evaluate experimental data being collected in an ongoing research project using a large-scale physical model aquifer. In addition, the model will be applicable to full-scale contamination sites. A final report of the investigations will be issued in October 1995. 68 ------- Screening Methods for Hydrocarbon Spills and Recovery INSTITUTE: Rice University and University of Texas (Jim Weaver, P.O.) TASK NO: 2078 PROJECT PERIOD: 02/92 -12/95 PRINCIPAL INVESTIGATOR: Herb Ward (713) 527-4086 Randy Charbeneau (713) 471 -0070 ABSTRACT: The objective of the project is to extend the Hydrocarbon Spill Screening Model to include additional processes and geologic settings. Five areas are proposed for the extension of the model. These include heterogeneous media in the vadose zone, volatilization of the chemical, flow of dense nonaqueous phase liquids (DNAPLs), biodegradation in the saturated zone, and flow of nonaqueous phase liquids (NAPLs) in the capillary fringe. For each of these extensions, the current understanding of the processes involved will be used to develop further conceptualizations. Based on the qualitative and quantitative understanding, an appropriate mathematical model will be developed. The models will, to the degree that is possible, be based on analytic or semi-analytic solutions of the mathematical models. The resulting models will be incorporated into existing Microsoft Windows user interface. The computer simulation models, user documentation, and Window user interface will be completed in December, 1995. Compilation of Saturated/Unsaturated Zone Models and Development and Application of Testing Methods and Benchmark Cases INSTITUTE: Colorado School of Mines (James McNabb, P.O.) TASK NO: 3038 PROJECT PERIOD: 10/91 10/94 PRINCIPAL INVESTIGATOR: Paul van der Heijde (303) 273-3800 ABSTRACT: The objectives of this project are to enhance the existing knowledge of ground-water models and their utility and performance, develop guidance in applying quality assurance in model development, and address other scientific issues related to the use of ground-water models. The approach to carrying out this project will be: (1) to enhance existing data bases on ground-water models, (2) characterize and analyze models for their utility and performance, (3) develop and apply testing and validation procedures to prominent public domain models, (4) develop and provide detailed guidance in the development of models, and (5) develop issue papers on critical topics in ground-water modeling. A Report on Analytical Solutions will be prepared along with a Report on the Status of Ground-Water Models. 69 ------- Evaluation of Ground-Water Pump-and-Treat Systems at the Gilson Road Superfund Site, Nashua, NH, with Ground-Water Models INSTITUTE: University of Cincinnati (Randall Ross, P.O.) TASK NO: 3068 PROJECT PERIOD: 10/92 09/94 PRINCIPAL INVESTIGATOR: Milovan Beljin (513) 556-5421 ABSTRACT: The objective of the project is to maximize the efficiency of the existing ground-water pump-and-treat system by modifying and enhancing previous ground-water modeling efforts at the site and to recommend system modifications to increase system efficiency. A database will also be prepared for use with GIS. Historical site information will be used to modify and enhance previous ground-water modeling efforts at the site to evaluate the performance of the existing ground- water remediation and determine the changes necessary to increase the efficiency of that system. A database will also be constructed to be utilized during future site assessments. An interim report will be prepared and a final report on the investigation will be prepared in September 1994. Application of Electromagnetic Tomography to Monitoring DNAPL INSTITUTE: University of Arizona (Carl Enfield, P.O.) TASK NO: 3073 PROJECT PERIOD: Proposal PRINCIPAL INVESTIGATOR: ABSTRACT: The objective of this project is to develop methods of mapping the movement of NAPLs through unconsolidated soils. The approach will be to evaluate the use of changes in dielectric permittivity to assess the spatial location of DNAPLs as a function of time. Data to evaluate the method will be supplied from studies taking place in RSKERL's large physical models. Output from this project will be available for evaluating models of DNAPL movement. 70 ------- Four-Dimensional Electrical Imaging of Subsurface Contaminants with Applications to a Controlled Spill INSTITUTE Massachusetts Institute of Technology (Carl Enfield, P.O.) TASK NO: 3074 PROJECT PERIOD: Proposal PRINCIPAL INVESTIGATOR: ABSTRACT: The objective of this project is to develop methods for three-dimensional mapping of the movement of NAPLs through unconsolidated soils. The approach will be to use low frequency current and evaluate induced polarization by organic chemistry. Data for this project will be supplied by RSKERL from studies taking place in its large physical models. Output from this project will be available for evaluating models of vadose zone transport of NAPLs. A Computer Program to Model Bioventing of Organic Contaminants in Unsaturated Geological Material INSTITUTE University of Michigan (Candida West, P.O.) TASKNO: 3080 PROJECT PERIOD: Proposal PRINCIPAL INVESTIGATOR: ABSTRACT: Bioventing is the process of delivering oxygen to the unsaturated zone through the advective flow of air. This task will develop and validate a 2-dimensional (vertical cross section) computer model that describes the transport and biotransformation of volatile organic compounds in the unsaturated zone. The model will incorporate physical, chemical, and microbiological processes that are known to occur in the real world, but are not well accounted for in current transport and fate models. This task will provide an improved computer model of bioventing (source codes and compiled versions, including a user's manual). 71 ------- Modeling Flow through Fractured Media-Testing Continuum vs. Discrete Conceptualizations INSTITUTE RSKERL TASK NO: 0384-RSSK1 PROJECT PERIOD: Pending PRINCIPAL INVESTIGATOR: Steve Kraemer (405) 436-8549 ABSTRACT: The objective of this task is to build conceptual understanding of flow through fractured media by testing mathematical representations within a computer model. The computer program will be used to test discrete fracture networks for their replacement by equivalent porous medium representations. Graphical output from the computer program will be used to document the emergence of preferred flow pathways within random distributions of fractures. Discrete flow can be a critical factor when designing wellhead protection areas or pump-and-treat systems for aquifer remediation. Evaluation of Multiphase Flow and Transport Models in a Large Two-Dimensional Physical Model INSTITUTE Cooperative Agreement TASK NO: 0939-001 PROJECT PERIOD: Proposal PRINCIPAL INVESTIGATOR: ABSTRACT: The objective of this project is to evaluate subsurface multiphase flow and transport models in a large two- dimensional physical model. A dual gamma system will be used to provide quantitative data on fluid composition and movement. Visual observations will be made to provide qualitative information on the fluid behavior. Many of the most commonly used multiphase codes are two dimensional, but there is a paucity of data with which to evaluate these models to determine their suitability for risk assessment and other decision making needs. Determination of Mass Transfer Rates between Mobile/Immobile Soil-Air Regions INSTITUTE RSKERL TASK NO: 0939-EADG1 PROJECT PERIOD: Pending PRINCIPAL INVESTIGATOR: Dominic DiGiulio (405) 436-8607 ABSTRACT: The objectives of this project are: (a)to modify mobile/immobile soil-water theory for application in gas flow models: quantify mass transfer rates between immobile gas/liquid regions and mobile gas regions in unsaturated soils; and (c) determine mass transfer rates as a function of volumetric moisture content and pore-gas velocity. Laboratory studies will be conducted using conservative gas tracers in soil columns to assess the effects of selected parameters on mass transfer rates. Models used for aqueous systems will be modified for gas flow use. 72 ------- Evaluation of Dual Source Gamma Ray Absorption System INSTITUTE: RSKERL TASK NO: 0939-RSED1 PROJECT PERIOD: Pending PRINCIPAL INVESTIGATOR: Eva Davis (405) 436-8548 ABSTRACT: The objective of this project is to test, and calibrate a dual energy gamma ray absorption system for making both quantitative and qualitative measurements of multiphase fluid flow in one- and two-dimensional physical models. The output for the project will be a User's Guide Dual Source for Gamma Ray Absorption. Development of Lagrangian Methods for Subsurface Contaminant Transport Analysis INSTITUTE: RSKERL TASK NO: 0939-RSJW4 PROJECT PERIOD: Pending PRINCIPAL INVESTIGATOR: James Weaver (405) 436-8545 ABSTRACT: The objective of this project is to evaluate the use of specific Lagrangian methods for the simulation of subsurface contaminant transport in heterogeneous porous media. A numerical model of subsurface contaminant transport which is particularly suited for coding for massively parallel computers will be developed using the concepts of Lagrangian fluid mechanics. A second phase of the project will particularly emphasize solutions for heterogenous geologic settings. The results of the model will be compared with known analytic solutions or data from physical models. A journal article will be published. Soil Vacuum Model INSTITUTE: RSKERL TASK NO: 0935-RSJC1 PROJECT PERIOD: Pending PRINCIPAL INVESTIGATOR: Jong Soo Cho (405) 436-8547 ABSTRACT: The objective of this project is to obtain data for parameters for a first-order kinetic model of soil vacuum extraction (SVE) under the operating conditions of laboratory soil columns, and for removal rates of volatile organic compounds from these columns under various operating conditions. The output chemical concentrations and residual mass of VOCs inside the soil will be fit to the proposed model with the least square method. The output of the project will be a peer-reviewed journal article. 73 ------- Intermediate-Scale Evaluation of Subsurface Transport and Fate Models INSTITUTE: Cooperative Agreement TASK NO: 0948-002 PROJECT PERIOD: Proposal PRINCIPAL INVESTIGATOR: ABSTRACT: The objective of this project is to use large-scale physical models or pilot-scale field sites to develop data sets that can be used to evaluate subsurface transport and fate models. The intermediate-scale evaluations will be conducted in conjunction with necessary laboratory work to independently evaluate model parameters. A Report on the Intermediate- Scale Evaluation of Subsurface Transport and Fate Models will be developed. Parameter Sensitivity Evaluation of Selected Unsaturated Zone Models INSTITUTE: RSKERL TASK NO: 0948-EAJW1 PROJECT PERIOD: Pending PRINCIPAL INVESTIGATOR: Joe Williams (405) 436-8608 ABSTRACT: The objective of this project is to evaluate the ability of various unsaturated zone models to predict the transport and fate of hazardous constituents remaining in soils following remediation. Sensitivity analysis will be performed on ten unsaturated zone models to quantitatively evaluate model result sensitivity to variations in model input parameters. Activities carried out under this task will compile the findings of related activities under Task Nos. 3036, 3037, and 3058. Sensitivity of Model Predicted Chemical Transport to Boundary Conditions at the Soil Surface INSTITUTE: RSKERL TASK NO: 0948-EAJW2 PROJECT PERIOD: Pending PRINCIPAL INVESTIGATOR: Joe Williams (405) 436-0608 ABSTRACT: The objective of this project is to evaluate the sensitivity of contaminant flux within the soil profile and at the water table to surface boundary conditions for water and chemicals. The approach will be to use the LEACHM model for the prediction of water movement and contaminant transport in the unsaturated zone to determine the degree of detail needed in surface boundary conditions for water recharge. Information will be developed to base decisions for recharge estimates for the determination of soil cleanup levels for remediation design purposes. The work will result in a project report or issue paper. 74 ------- EIT Inverse Solution INSTITUTE: RSKERL TASK NO: 0948-RS JC3 PROJECT PERIOD: Pending PRINCIPAL INVESTIGATOR: Jong Soo Cho (405) 436-8547 ABSTRACT: The objective is to solve the inverse resistivity problem for a three dimensional heterogeneous media based on experimental data obtained from physical model at RSKERL. Future allocations will be used to expand the solution to include dialectric properties in addition to the resistive properties. The electrical properties of an aquifer are made up of two primary components: resistivity and permittivity. 75 ------- TECHNICAL ASSISTANCE AND INFORMATION TRANSFER The application of research results through technical assistance on a variety of environmental issues has been a tradition at the RSKERL since its beginning in 1965. Even though the Laboratory gained a national and international reputation for its research, it was not until 1986 that events occurred which led to a structured program in technical assistance and made it an integral part of the Laboratory's activities, particularly with regard to the remediation of soil and ground water at hazardous waste sites. Following the Superfund Amendments and Reauthorization Act of 1986, Regional decision makers, charged with administering cost-effective and permanent restoration technologies at Superfund Sites, quickly became overburdened by the technical complexity of this responsibility. Informed decisions concerning soils and ground-water remediation required a broad, interdisciplinary, state-of-the-science level of expertise in a rapidly developing and complex environmental field. In 1987, in order to make EPA's Office of Research and Development scientists more accessible to Regional decision makers, the Office of Solid Waste and Emergency Response (OSWER) provided direct funding to ORD laboratories in Las Vegas, Cincinnati, Athens, and Ada to establish Superfund Technology Support Centers. The goal of the RSKERL Technology Support Program is to provide state-of-science technical support to those charged with making decisions concerning ground water protection and restoration, especially site remediation decision makers, Remedial Project Managers (RPMs), and On-Scene Coordinators (OSCs). This is accomplished through (1) direct, site-specific technical assistance, (2) state-of-the-science information on subsurface remedial technologies and the transport and fate of subsurface contaminants, and (3) improved modeling and assessment tools for dealing with Superfund sites. The RSKERL Technology Support Program completed its sixth year of service at the end of 1993. In addition to its technology transfer activities, the TSC has 725 active or completed site specific projects encompassing an involvement at a total of over 375 Superfund and RCRA sites. The RSKERL-Ada Technology Support Program operates the Center for Subsurface Modeling Support (CSMoSJ, the Subsurface Remediation Information Center (SRIC), and the Ground Water Remediation Technologies Analysis Center (GWRTACJ. CSMoS provides direct technical support to EPA and State decision makers in subsurface model applications, in addition to managing, distributing and supporting the ground water and vadose zone models and databases resulting from research at RSKERL. SRIC is a database designed to provide site specific information concerning subsurface contamination and remediation activities presently being conducted or proposed at hazardous waste sites throughout the United States. GWRTAC is a joint undertaking with industry, academia, professional societies, EPA and other Federal Agencies to develop a knowledge base of the status of ongoing in-situ ground-water remediation technology development and demonstration efforts with emphasis on evaluating those efforts with respect to their applicability to remediating subsurface contamination at hazardous waste sites. In addition to Superfund, which remains the major client, the RSKERL TSC provides assistance to Headquarters, Regional, and State personnel responsible for RCRA corrective actions, Underground Storage Tanks, Pesticides, the Underground Injection Control Program, and the Wellhead Protection Program. 77 ------- PUBLICATIONS During RSKERL's tenure of operation, a large number of reports and other types of documents dealing with environmental problems have been published. A list of those publications for the period 1992 to the present is presented in this section. These can be obtained as described below. A full list of publications (1967-1994) is available upon request from RSKERL. Publications containing an NTIS number should be obtained from: National Technical Information Service U.S. Department of Commerce Springfield, VA 22161 (703) 557-4560 Other publications can be requested from: Robert S. Kerr Environmental Research Laboratory P.O.Box 1198 Ada, OK 74820 (405)436-8651 78 ------- 1992 ABIOTIC TRANSFORMATION OF CARBON TETRACHLORIDE IN THE PRESENCE OF SULFIDE AND MINERAL SURFACES M.R. Kriegman-King and M. Reinhard American Chemical Society, Division of Environmental Chemistry; preprints of papers presented at the 203rd ACS National Meeting; April 5-10, 1992, San Francisco, CA, 2(2):495-498 EPA-600/A-92-097, NTIS PB 92-179738 ACQUISITION OF REPRESENTATIVE GROUND WATER QUALITY SAMPLES FOR METALS R.W. Puls and R.M. Powell Special "focus" issue of Ground Water Monitoring Review, Summer 1992, 12(3): 167-176 EPA-600/J-92-308, NTIS PB 92-227487 AN EXACT PEAK CAPTURING AND OSCILLATION-FREE SCHEME TO SOLVE ADVECTION- DISPERSION TRANSPORT EQUATIONS G. Yeh, J. Chang and T.E. Short Water Resources Research, 28(11 ):2937-2951 EPA-600/J-92-409, NTIS PB 93-131845 AN OPTIMAL ADAPTIVE LOCAL GRID REFINEMENT APPROACH TO MODELING CONTAMINANT TRANSPORT G. Yeh, K.A. Kane and T.E. Short Computational Methods in Water Resources IX (1): Numerical Methods in Water Resources, Computational Mechanics Publication, pp. 659-667 EPA-600/A-92-182, NTIS PB 92-217314 APPLIED GEOLOGIC, MICROBIOLOGICAL, AND ENGINEERING CONSTRAINTS OF IN-SITU BTEX BIOREMEDIATION L. Kennedy and S.R. Hutchins Remediation, Winter 1992/1993, 3(1):83-107 EPA-600/J-92-450, NTIS PB 93-141497 *BASIC CONCEPTS OF CONTAMINANT SORPTION Superfund Technology Support Center for Ground Water, Robert S. Kerr Environmental Res. Lab. EPA-540/S-92-016, NTIS PB 93-146835 *BEHAVIOR OF METALS IN SOILS J.E. McLean and B.E. Bledsoe EPA-540/S-92-018, NTIS PB 93-131480 *BIODEGRADATION OF ATRAZINE IN SUBSURFACE ENVIRONMENTS J.L. Sinclair and T.R. Lee EPA-600/S-91-001 BIOREMEDIATION J.M. Thomas, C.H. Ward, R.L. Raymond, J.T. Wilson and R.C. Loehr Book Chapter in the Encyclopedia of Microbiology, l(A-C): by Academic Press, Inc., 1992 EPA-600/A-93-004, NTIS PB 93-149193 *Publications denoted by an asterisk (*) are readily available from RSKERL. 79 ------- BIOSORPTION OF DICHLORODIPHENYLTRICHLOROETHANE AND HEXACHLOROBENZENE IN GROUND WATER AND ITS IMPLICATIONS FOR FACILITATED TRANSPORT R. Lindqvist and C.G. Enfield Applied and Environmental Microbiology, 58(7):2211-2218 EPA-600/J-92-452, NTIS PB 93-141513 *A BIOVENTING APPROACH TO REMEDIATE A GASOLINE CONTAMINATED SUBSURFACE D.H. Kampbell, J.T. Wilson and CJ. Griffin Published in: Emerging Technologies for Hazardous Waste Management, 1991 Book of Abstracts for the Special Symposium, Atlanta GA, Industrial & Eng. Chemistry Div., American Chemical Society, Oct. 1-3, 1991 EPA-600/A-92-220, NTIS PB 93-119816 BIOVENTING RECLAMATION PILOT PROJECT-AVIATION GASOLINE SPILL D.H. Kampbell, J.T.Wilson, C.J. Griffin and D.W. Ostendorf Tech Trends, June 1992 CAPTURE ZONE DELINEATION USING THE ANALYTIC ELEMENT METHOD: A COMPUTER MODELING DEMONSTRATION FOR THE ELLIS COUNTY (KANSAS) WELLHEAD PROTECTION COMMITTEE Stephen R. Kraemer and David S. Burden Ground Water Mgmt. Book 9 of the Series Proceedings of the 1992 Solving Ground Water Problems with Models Conference, p. 697 CELL DENSITY AND NON-EQUILIBRIUM SORPTION EFFECTS ON BACTERIAL DISPERSAL IN GROUND WATER MICROCOSMS R. Lindqvist and C.G. Enfield Microbial Ecology, 24:25-42, Nov. 1992 EPA-600/J-92-451, NTIS PB 93-141505 *CHEMICAL ENHANCEMENTS TO PUMP-AND-TREAT REMEDIATION C.D. Palmer and W. Fish EPA-540/S-92-001, NTIS PB 92-180074 COLLOIDAL TRANSPORT IN SANDY AQUIFER MATERIAL: SURFACE AND AQUEOUS CHEMICAL EFFECTS R.W. Puls, D.A. Clark and C.J. Paul In: Proceedings, 1992 Fall Meeting American Geophysical Union, A Supplement to EOS, H12A, p. 167, Oct. 1992 COLUMN STUDIES ON BTEX BIODEGRADATION UNDER MICROAEROPHILIC AND DENITRIFYING CONDITIONS Stephen R. Hutchins, S.W. Moolenaar and D.E. Rhodes Ground Water: The Problem and Some Solutions, Proceedings: 4th Annual Symposium The Gulf Coast Hazardous Substance Research Center, Beaumont, TX, April 2-3, 1992, pp. 67-90 EPA-600/A-92-080, NTIS PB 92-179050 Jnl. of Hazardous Materials, 32:195-214, 1992, Elsevier Science Publishers B.V., Amsterdam EPA-600/J-93-042, NTIS PB 93-158962 80 ------- COMPARISON BETWEEN MODEL SIMULATIONS AND HELD RESULTS FOR IN-SITU BIORESTORATION OF CHLORINATED ALIPHATICS: PART 2. COMETABOLIC TRANSFORMATIONS L. Semprini and P.L. McCarty Ground Water, 30(l):37-44, January-February, 1992 COMPARISON OF GROUND-WATER SAMPLING DEVICES BASED ON EQUILIBRATION OF WATER QUALITY INDICATOR PARAMETERS C. Paul and R. Puls In: Proceedings, National Ground Water Sampling Symposium, Washington, DC, 11-30-92, pp. 21-39 EPA-600/A-93-005, NTIS PB 93-149201 CRITICAL EVALUATION OF TREATMENT TECHNOLOGIES WITH PARTICULAR REFERENCE TO PUMP-AND-TREAT SYSTEMS S.G. Schmelling, C.G. Enfield and J.W. Keeley Elsevier Applied Science, London and New York, for SCI Water and Environmental Group. Proceedings of Contaminated Land Treatment Technologies, pp. 220-234 EPA-600/A-92-224, NTIS PB 93-119857 *DENSE NONAQUEOUS PHASE LIQUIDS-A WORKSHOP SUMMARY Robert S. Kerr Environmental Research Laboratory EPA-600/R-92-030, NTIS PB 92-178939 *DETECTING WATER FLOW BEHIND PIPE IN INJECTION WELLS J.T. Thomhill and B. G. Benefield EPA-600/R-92-041, NTIS PB 92-239532 DISTRIBUTION, SPECIATION, AND TRANSFORMATION OF CHROMIUM IN CONTAMINATED SOILS Robert W. Puls, D.A. Clark, and C.J. Paul 203rd American Chemical Society National Meeting, San Francisco, CA, April 5-10, 1992, 32(l):455-457 EPA-600/A-92-084, NTIS PB 92-179092 EPA's MASTER RESEARCH PLAN M.D. Jawson, R. Swank, A.R. Carlson, C.A. Ribic and M. Hewitt Agronomy Abstracts, Nov. 1-6, 1992, Minneapolis, MN, p. 328 EPA's SUPERFUND TECHNICAL SUPPORT PROJECT M.R. Scalf Journal of Hazardous Materials, 32(2+3): 313-319, Elsevier Science Publishers B.V., Amsterdam * Not available NTIS ESTIMATING AQUIFER PROPERTIES BY NONLINEAR LEAST-SQUARES ANALYSIS OF PUMP TEST RESPONSE R.A. Johns, L. Semprini, and P.V. Roberts Ground Water, 30(l):68-77, January-February 1992 81 ------- *EVALUATION OF SOIL VENTING APPLICATION D.C. DiGiulio EPA-540/S-92-004, NTIS PB 92-232362 *FUNDAMENTALS OF GROUND-WATER MODELING J. Bear, M.S. Beljin and R.R. Ross EPA-540/S-92-005, NTIS PB 92-232354 *GENERAL METHODS FOR REMEDIAL OPERATION PERFORMANCE EVALUATION Robert S. Kerr Environmental Research Laboratory EPA-600/R-92/002, NTIS PB 92-166842 IMPROVED METALS SAMPLING TECHNIQUES FOR GROUND WATER R.W. Puls Tech Trends, 7:2, December 1991 EPA-540/M-91-005 INHIBITION OF ALKYLBENZENE BIODEGRADATION UNDER DENITRIFYING CONDITIONS BY USING THE ACETYLENE BLOCK TECHNIQUE S.R Hutchins Applied and Environmental Microbiology, 58(10):3395-3398, Oct. 1992 EPA-600/J-92-393, NTIS PB 93-121242 *IN-SITU BIOREMEDIATION OF CONTAMINATED GROUND WATER J.L. Sims, J.M. Suflita and H.H. Russell EPA-540/S-92-003, NTIS PB 92-224336 *IN-SITU BIOREMEDIATION OF GROUND WATER Superfund Technology Support Center for Ground Water EPA-540/S-92-017, NTIS PB 93-146850 IN-SITU TRANSFORMATION OF CARBON TETRACHLORIDE AND OTHER HALOGENATED COMPOUNDS RESULTING FROM BIOSTIMULATION UNDER ANOXIC CONDITIONS L. Semprini, G.D. Hopkins, P.L. McCarty, and P.V. Roberts Env. Sci. and Tech., 26:2454-2461, 1992 LANDFILL LEACHATE EFFECTS ON SORPTION OF ORGANIC MICROPOLLUTANTS ONTO AQUIFER MATERIALS T. Larsen, T.H. Christensen, P.M. Pfeffer and C.G. Enfield Jnl. Contaminant Hydrology, 9(4):307-324, April 1992 EPA-600/J-92-235, NTIS PB 92-198597 LANDFILL LEACHATE EFFECTS ON TRANSPORT OF ORGANICS IN AQUIFER MATERIALS P.M. Pfeffer and C.G. Enfield Transport and Remediation of Subsurface Contaminants, ACS Symposium Series 491, June 1991, pp. 194-204 EPA-600/A-92-142, NTIS PB 92-198225 82 ------- LARGE-SCALE NATURAL GRADIENT TRACER TEST IN SAND AND GRAVEL, CAPE COD, MASSACHUSETTS, s. HYDRAULIC CONDUCTIVITY VARIABILITY AND CALCULATED MACRODISPERSIVITIES K.M. Hess, S.H. Wolf and M.A. Celia Water Resources Research, 28(8):2011-2027, August 1992 EPA-600/J-92-359, NTIS PB 93-107050 LIMITING FACTORS IN GROUND-WATER REMEDIATION C.W. Hall and J.A. Johnson Journal of Hazardous Materials, 32(1992):215-225, Elsevier Science Publishers B.V., Amsterdam * Not available NTIS *LNAPL DISTRIBUTION AND HYDROCARBON VAPOR TRANSPORT IN THE CAPILLARY FRINGE D.W. Ostendorf, E.E. Moyer, R.J. Richards, E.S. Hinlein, Y. Xie and R.V. Rajan EPA-600/R-92-247, NTIS PB 93-157550 * A MANUAL OF INSTRUCTIONAL PROBLEMS FOR THE U.S.G.S. MODFLOW MODEL P.P. Anderson EPA-600/R-93-010 METALS IN GROUND WATER: SAMPLING ARTIFACTS AND REPRODUCIBILITY R.W. Puls, D. Clark, B. Bledsoe, R.M. Powell and CJ. Paul Hazardous Waste & Hazardous Materials, 9(2): 149-162 EPA-600/J-92-307, NTIS PB 92-227479 *METHODOLOGIES FOR EVALUATING IN SITU BIOREMEDIATION OF CHLORINATED SOLVENTS L. Semprini, D. Grbic-Galic, P.L. McCarty, and P.V. Roberts EPA-600/R-92-042, NTIS PB 92-146943 MICROBIAL DEGRADATION OF TOLUENE UNDER SULFATE-REDUCING CONDITIONS AND THE INFLUENCE OF IRON ON THE PROCESS H.R. Beller, D. Grbic-Galic and M. Reinhard Applied and Environmental Microbiology, 58(2):786-793, March 1992 EPA-600/J-92-139, NTIS PB 92-166735 MOBILIZATION OF NATURALLY PRESENT ARSENIC FROM ALTERATION OF AQUIFER GEOCHEMISTRY DUE TO WASTE DISPOSAL R.W. Puls, D.A. Clark, B. Bledsoe and CJ. Paul Poster Presentation at ASA-CSSA-SSSA 1992 Annual Meeting, November 1-6, 1992, Minneapolis, MN Agronomy Abstracts: pp. 54, Nov. 1992 MODELING CONTAMINANT TRANSPORT THROUGH SUBSURFACE SYSTEMS R.J. Charbeneau, J.W. Weaver In: Proceedings, 4th Annual Symposium Ground Water: The Problem and Some Solutions, Lamar University, Beaumont, Texas, April 2-3, 1992, pp. 179-198 EPA-600/A-92-086, NTIS PB 92-179118 Jnl. of Haz. Materials, 32(1992):293-311, EPA-600/J-93-027, NTIS PB 93-156313 83 ------- MODELING VADOSE ZONE CHEMICAL TRANSPORT IN MULTIPHASE FLOW SYSTEMS J.W. Weaver and B.K. Lien Agronomy Abstracts, November 1-6, 1992, pp. 230-231 *MULTIPHASE CHEMICAL TRANSPORT IN POROUS MEDIA J.F. Guarnaccia, P.T. Imhoff, B.C. Missildine, et al. EPA-600/S-92-002, NTIS PB 92-205640 A NEW TWO-PHASE FLOW AND TRANSPORT MODEL WITH INTERPHASE MASS EXCHANGE J.F. Guarnaccia and G.F. Finder Computational Mechanics Publications; co-published with: Elsevier Applied Science, 2: Mathematical Modeling in Water Resources, June 1992, pp. 281-288 EPA-600/A-92-156, NTIS PB 92-206564 OVERVIEW OF DNAPL RESTORATION R. R. Ross and S.D. Acree In: Pre-Conference Seminar Proceedings, "Detection and Restoration of DNAPLs in Groundwater at Hazardous Waste Sites," New Orleans, LA, Sep. 19-20, 1992, pp. 67-73. Water Environment Federation, Alexandria, VA. PARALLEL GROUNDWATER COMPUTATIONS USING PVM MJ. Eppstein, J. F. Guarnaccia and D.E. Dougherty Computational Mechanics Publications; co-published with: Elsevier Applied Science, 1: Numerical Methods in Water Resources, June 1992, pp. 713-720 EPA-600/A-92-157, NTIS PB 92-206572 PILOT SCALE FIELD STUDIES ON IN SITU BIOREMEDIATION OF CHLORINATED SOLVENTS L. Semprini, G.D. Hopkins, P.V. Roberts, and P.L. McCarty Jnl. Hazardous Materials, 32:145-162, 1992 PNEUMATIC PUMP TEST FOR DESIGN OF SOIL VACUUM EXTRACTION J.S. Cho and D.C. DiGiulio Environ. Progress. II: (3):228-233, Sep. 92 EPA-600/J-92-391, NTIS PB 93-121234 PROCEEDINGS OF THE SYMPOSIUM ON SOIL VENTING Sponsors: Robert S. Kerr Environmental Research Laboratory, Ada, OK and National Center for Ground Water Research, Rice University, Houston, TX Presented at the Symposium on Soil Venting, Houston, TX, April 29-May 1, 1991 EPA-600/R-92-174, NTIS PB 93-122323 RELATIONSHIP BETWEEN SOIL GAS, WATER QUALITY, AND CORE MATERIAL AT AN AVIATION GASOLINE SPILL SITE D. Kampbell and J. Wilson In: Proceedings, Conference on Hazardous Waste Research, May 29 and 30,1991, Kansas State University, Manhattan, KS, pp. 579-587 SCREENING MODEL FOR SUBSURFACE HYDROCARBON SPILLS RJ. Charbeneau, J. Tauxe, J.W. Weaver and B.K. Lien Agronomy Abstracts, Nov. 1-6, 1992, p. 79 84 ------- SIMULATING SOLUTE TRANSPORT USING LABORATORY-BASED SORPTION PARAMETERS T.C. Harmon, L. Semprini, and P.V. Roberts Journal of Environmental Engineering, 118(5):666-689, September-October 1992 STABILITY AND TRANSPORT OF INORGANIC COLLOIDS THROUGH CONTAMINATED AQUIFER MATERIAL R.W. Puls, R.M. Powell and T.F. Rees In: Proceedings, U.S. Geological Survey Toxic Substances Hydrology Program Technical Meeting, Monterey, CA, March 11-15, 1991, pp. 507-510. EPA-600/A-92-068, NTIS PB 92-164839 STIMULATION OF REDUCTIVE DECHLORINATION OF TETRACHLOROETHENE (PCE) IN ANAEROBIC AQUIFER MICROCOSMS BY ADDITION OF SHORT-CHAIN ORGANIC ACIDS OR ALCOHOLS S.A. Gibson and G.W. Sewell Applied and Environmental Microbiology, 58(4): 1392-1393, April 1992 EPA-600/J-92-266, NTIS PB 92-206465 SUBSURFACE CONTAMINATION BY DENSE NONAQUEOUS PHASE LIQUIDS-AN OVERVIEW J.W. Weaver and S.G. Huling In: Pre-Conference Seminar Proceedings, "Detection and Restoration of DNAPLs in Ground water at Hazardous Waste Sites," New Orleans, LA, Sep. 19-20, 1992, pp. 3-22, Water Environment Federation, Alexandria VA. SURFACE-CHARGE REPULSIVE EFFECTS ON THE MOBILITY OF INORGANIC COLLOIDS IN SUBSURFACE SYSTEMS R.W. Puls and R.M. Powell American Chemical Society, ACS Symposium Series 491, pp. 40-54 EPA-600/A-92-118, NTIS PB 92-191139 SURFACTANTS AND SUBSURFACE REMEDIATION C.C. West and J.H. Harwell Environmental Science Technology, 26(12):2324-2330 EPA-600/J-93-005, NTIS PB 93-149854 SURFACTANT-ENHANCED SOLUBILIZATION OF TETRACHLOROETHYLENE AND DEGRADATION PRODUCTS IN PUMP AND TREAT REMEDIATION C.C. West American Chemical Society, ACS Symposium Series 491, pp. 149-158 EPA-600/A-92-117, NTIS PB 92-191121 *TCE REMOVAL FROM CONTAMINATED SOIL AND GROUND WATER H.H. Russell, J.E. Matthews and G.W. Sewell EPA-540/S-92-002, NTIS PB 92-224104 TRANSFORMATION OF CARBON TETRACHLORIDE IN THE PRESENCE OF SULFIDE, BIOTITE, AND VERMICULITE M. Kriegman-King Environ. Sci. Tech., 26(11):2198-2206 EPA-600/J-92-414, NTIS PB 93-135713 85 ------- TRANSPORT OF INORGANIC COLLOIDS THROUGH NATURAL AQUIFER MATERIAL: IMPLICATIONS FOR CONTAMINANT TRANSPORT R.W. Puls and R.M. Powell Environ. Sci. Techno!., 26(3):614-621, 1992 EPA-600/J-92-113, NTIS PB 92-158690 VIRTUS, A MODEL OF VIRUS TRANSPORT IN UNSATURATED SOILS M.V. Yates and Y. Ouyang Applied and Environmental Microbiology, 58 (5):1609-1616, May 1992 EPA-600/J-93-142, NTIS PB 93-185890 1993 AEROBIC SOIL MICROCOSMS FOR LONG-TERM BIODEGRADATION OF HYDROCARBON VAPORS RJ. Richards, D.W. Ostendorf and M.S. Switzenbaum Hazardous Wastes & Hazardous Materials, 9(4):397-410,1992 EPA-600/J-93-131, NTIS PB 93-181196 BIOREMEDIATION OF CHLORINATED SOLVENTS IN THE VADOSE ZONE D.H. Kampbell and B.H. Wilson In: Proceedings, In Situ and On-Site Bioreclamation. The 2nd Internationa] Symposium, San Diego, CA, April 5-8, 1993 EPA-600/A-93-175, NTIS PB 93-221935 *BIOREMEDIATION USING THE LAND TREATMENT CONCEPT D.E. Pope and I.E. Matthews EPA-600/R-93-164, NTIS PB 94-107927 BIOTRANSFORMATION AND MINERALIZATION OF ALKYBENZENES UNDER DENITRIFYING CONDITIONS S.R. Hutchins Environmental Toxicology and Chemistry, 12(8): 1413-1423, August 1992 BIOTREATABILITY OF A VADOSE ZONE SOIL CONTAMINATED WITH DIOCTYL PHTHALATE D. Kampbell, D. Fine and J. Anderson In: Symposium on Bioremediation of Hazardous Wastes: Research, Development, and Field Evaluations, Dallas, TX, May 4-6, 1993 EPA-600/R-93-054, EPA-600/A-93-177, NTIS PB 93-221950 COMBINING TREATABILITY STUDIES AND SITE CHARACTERIZATION FOR RATIONAL DESIGN OF IN SITU BIOREMEDIATION USING NITRATE AS ELECTRON ACCEPTOR S.R. Hutchins, D.H. Kampbell, M.L. Cook, P.M. Pfeffer, R.L. Cosby, and J.T. Wilson In: Symposium on Bioremediation of Hazardous Wastes: Research, Development, and Field Evaluations, Dallas, TX, May 4-6, 1993, pp. 90-99 EPA-600/R-03-054 EPA-600/A-93-172, NTIS PB 93-221901 86 ------- COMPARISON OF BIO VENTING AND AIR SPARGING FOR IN-SITU BIOREMEDIATION OF FUELS D. Kampbell, C.J. Griffin, F.A. Blaha In: Symposium on Bioremediation of Hazardous Wastes: Research, Development, and Field Evaluation, Abstract, Dallas, TX, May 4-6, 1993, pp. 61-67 EPA-600/R-93-054 *COMPILATION OF GROUND-WATER MODELS P.K.M. van der Heijde and O.A. Elnawawy EPA-600/R-93-118, NTIS PB 93-209401 *COMPLEX MIXTURES AND GROUND WATER QUALITY M.L. Brusseau EPA-600/S-93-004 DETERMINATION OF CARBOXYLIC ACIDS BY ION-EXCLUSION CHROMATOGRAPHY WITH NON-SUPPRESSED CONDUCTIVITY AND OPTICAL DETECTORS M.Y. Ye, K.D. Hill and R.C.Walkup Chromatographia, 35(3/4): 139-141 EPA-600/J-93-133, NTIS PB 93-181212 DETERMINATION OF CAPILLARY PRESSURE-SATURATION CURVES INVOLVING TCE, WATER AND AIR FOR A SAND AND A SANDY CLAY LOAM J.H. Dane, M. Oostrom and B.C. Missildine EPA-600/R-94-005, NTIS PB 94-130754 DEVELOPMENT AND APPLICATION OF BOREHOLE FLOWMETERS FOR ENVIRONMENTAL ASSESSMENT F.J. Molz and S.C. Young The Log Analyst, January-February, 1993, pp. 13-23 EPA-600/J-93-134, NTIS PB 93-185817 DEVELOPMENT OF SPLIT-OPERATOR, PETROV-GALERKIN METHODS TO SIMULATE TRANSPORT AND DIFFUSION PROBLEMS C.T. Miller and A.J. Rabideau Water Resources Research, 29(7):2227-2240, July 1993 EPA-600/J-93-421, NTIS PB 94-101722 DNAPL SITE EVALUATION R.M. Cohen and J.W. Mercer EPA-600/R-93-022, NTIS PB 93-150217 EVALUATING PARAMETER ESTIMATION TECHNIQUES APPLIED IN VADOSE ZONE MODELING J.W. Weaver, J. Johnson, V. Ravi, and B.K. Lien In: Proceedings, "1993 Ground Water Modeling Conference," June 9-12,1993, Golden, CO, pp. 1-115 through 1-126. International Ground International Ground Water Modeling Center, Colorado School of Mines, Golden, CO. EPA-600/A-93-148, NTIS PB 93-212371 87 ------- EXPERIMENTAL EVALUATION OF THE MATHEMATICAL MODEL FOR IN SITU AQUIFER RESTORATION PROCESSES T.E. Short and G.T. Yeh Advances in Hydro-Science and Engineering, 1(B): 1807-1812 EPA-600/A-93-147, NTIS PB 93-212363 GEOCHEMICAL INDICATORS OF ANAEROBIC BIODEGRADATION OF BTEX D.H. Kampbell, J.T. Wilson, S.R. Hutchins, L.G. Kennedy and B.H. Wilson Proceedings of the Conference on Hazardous Waste Research, June 1 & 2, 1992, pp. 563-575 HIERARCHICAL APPROACH TO MODELING SURFACE-GROUNDWATER INTERACTIONS: THE WALNUT CREEK (IOWA) WATERSHED IN REGIONAL PERSPECTIVE H.M. Haitjema and S. Mitchell-Bruker Extended abstract to appear in the proceedings of the conference, "Agricultural Research to Protect Water Quality," Soil and Water Conservation Society, Minneapolis, MN, February 21-24, 1993 HOT WATER ENHANCED REMEDIATION OF HYDROCARBON SPILLS E.L. Davis In: Proceedings of ACS-I&EC Symposium, September 27, 1993, Atlanta, GA HYDROCARBON VAPOR DIFFUSION IN INTACT CORE SLEEVES D.W. Ostendorf, Z.E. Moyer, Y. Xie and R.V. Rajan Ground Water Monitoring and Remediation, 13(1): 139-150, Winter EPA-600/J-93-132, NTIS PB 93-181204 *IN SITU BIOREMEDIATION OF CONTAMINATED UNSATURATED SUBSURFACE SOILS J.L. Sims, R.C. Sims, R.R. Dupont, J.E. Matthews and H.H. Russell EPA-540/S-93-501, NTIS PB 93-234565 *IN SITU BIOREMEDIATION OF CONTAMINATED VADOSE ZONE SOIL Superfund Technology Support Center for Ground Water (Summary paper) EPA-540/S-93-502 IN SITU BIOREMEDIATION OF GROUND WATER AND GEOLOGICAL MATERIAL: A REVIEW OF TECHNOLOGIES R.D. Norris, R.E. Hinchee, R. Brown, P.L. McCarty, L. Semprini, J.T.Wilson, D.H. Kampbell, M. Reinhard, EJ. Bouwer, R.C. Borden, T.M. Vogel, J. Thomas and C.H. Ward EPA-600/R-93-124, NTIS PB 93-215564, (Project Summary) EPA-600/SR-93-124 LABORATORY STUDY ON THE USE OF HOT WATER TO RECOVER LIGHT OILY WASTES FROM SANDS E.L. Davis and Bob K. Lien EPA-600/R-93-021, NTIS PB 93-167906 LABORATORY STUDIES ON THE STABILITY AND TRANSPORT OF INORGANIC COLLOIDS THROUGH NATURAL AQUIFER MATERIAL R.W. Puls and R.M. Powell Manipulation of Groundwater Colloids for Environmental Restoration, Chapter 49 pp. 305-307, 1993 EPA-600/A-93-072, NTIS PB 93-175537 ------- LNAPL RETENTION IN SANDY SOIL D.W. Ostendorf, R.J. Richards, and P.P. Beck Ground Water, 31(2): 285-292, March-April 1993 * Not available from NTIS LOSS OF ORGANIC CHEMICALS IN SOIL: PURE COMPOUND TREATABILITY STUDIES R.C. Loehr and J.E. Matthews Journal of Soil Contamination, 1(4):339-360, Oct-Nov-Dec 1992 MECHANICAL INTEGRITY TESTING AND TRAINING FACILITY J.T. Thornhill Jnl. Applied Ground-Water Remediation, l(l):37-43 MICROCOSM AND IN SITU FIELD STUDIES OF ENHANCED BIOTRANSFORMATION OF TRICHLOROETHYLENE BY PHENOL-UTILIZING MICROORGANISMS G.D. Hopkins, P.L.McCarty and L. Semprini Applied & Environmental Microbiology, 59(7):2277-2285 MODELING TWO-DIMENSIONAL SUBSURFACE FLOW, FATE AND TRANSPORT OF MICROBES AND CHEMICALS J.C. Cheng, G. Yeh and T.E. Short Presented at 1993 National Conference on Hydraulic Engineering and International Symposium on Engineering Hydrology, July 25-30, 1993, San Francisco, CA *Not available from NTIS MOLECULAR SIZE EXCLUSION BY SOIL ORGANIC MATERIALS ESTIMATED FROM THEIR SWELLING IN ORGANIC SOLVENTS W.G. Lyon and D.E. Rhodes Environmental Toxicology and Chemistry, pp. 1405-1412, July 1993 PASSIVE SAMPLING OF GROUND WATER MONITORING WELLS WITHOUT PURGING: MULTILEVEL WELL CHEMISTRY AND TRACER DISAPPEARANCE R.M. Powell and R.W. Puls Journal Contaminant Hydrology, 12:51-77, Feb. 93 EPA-600/J-93-129, NTIS PB 93-181170 PERFORMANCE AND COST EVALUATION OF BIOREMEDIATION TECHNIQUES FOR FUEL SPILLS C.H. Ward, J.T. Wilson, D.H. Kampbell, and S.R. Hutchins In-Situ Bioremediation Symposium 92, Sep. 20-24, 1992, pp. 15-21 EPA-600/A-93-073, NTIS PB 93-175545 PERFORMANCE OF PILOT SCALE BIOVENTING AT AN AVIATION GASOLINE SPILL SITE D.H. Kampbell Book Chapter to be published in the Proceedings of the Environmental Restoration Technology Transfer Symposium held on January 26-27, 1993, at Elgin AFB, San Antonio, Texas. Sponsored by the U.S. Air Force Center for Environmental Excellence. EPA-600/A-93-176, NTIS PB 93-221943 89 ------- PRACTICAL SIMULATION OF COMPOSTING IN THE LABORATORY A.M.T. Magalhaes, PJ. Shea, M.D. Jawson, E.A. Wicklund and D.W. Nelson Waste Management & Research, 11:143-154, 1993 EPA-600/J-93-271, NTIS PB 93-222099 PROTOZOA IN SUBSURFACE SEDIMENTS FROM SITES CONTAMINATED WITH AVIATION GASOLINE OR JET FUEL J.L. Sinclair, D.H. Kampbell, M.L.Cook, and J.T. Wilson Applied & Environmental Microbiology, 59(2):467-472, Feb. 1993 EPA-600/J-93-279, NTIS PB 93-221919 *QUALITY ASSURANCE AND QUALITY CONTROL IN THE DEVELOPMENT AND APPLICATION OF GROUND-WATER MODELS P.K.M. van der Heijde and O.A. Elnawawy EPA-600/R-93-011, NTIS PB 93-178226 RAPID PHASE IDENTIFICATION OF MIXED CRYSTALLINE SOLIDS J.T. Stanley II, C.D. Palmer, D.A. Dunham, et al. Book Chapter, Proceedings of Symposium, The Minerals, Metals & Materials Society, TMS Mtgs. 2/93, pp. 433-445 EPA-600/A-93-146, NTIS PB 93-212355 RETROSPECTIVE PERFORMANCE EVALUATION ON IN SITU BIOREMEDIATION SITE CHARACTERIZATION J.T.Wilson and D.H. Kampbell Symposium on Bioremediation of Hazardous Wastes: Research, Development, and Field Evaluation, Dallas, TX, May 1993, pp. 3-9 EPA-600/A-93-173, NTIS PB 93-221919 SOIL SORPTION OF VOLATILE AND SEMIVOLATILE ORGANIC COMPOUNDS IN A MIXTURE B.T. Walton, M.S. Hendricks, C.W. Francis, W.H. Griest, R. Merriweather, JJ. Beauchamp, T.A. Anderson Journal of Environmental Quality, 21(4):552-558 EPA-600/J-93-130, NTIS PB 93-181188 SPATIAL HETEROGENEITY OF GEOCHEMICAL AND HYDROLOGIC PARAMETERS AFFECTING METAL TRANSPORT IN GROUND WATER J.A. Davis, J.A. Coston, C.C. Fuller, E. Dixon and K.M. Hess EPA-600/S-93-006, NTIS PB 94-114774 *SUGGESTED OPERATING PROCEDURES FOR AQUIFER PUMPING TESTS P.S. Osborne EPA-540/S-93-503, NTIS PB 94-107943 SURFACE CHEMICAL EFFECTS ON COLLOID STABILITY AND TRANSPORT THROUGH NATURAL POROUS MEDIA R.W. Puls, D.A. Clark and C.J. Paul Colloids and Surfaces A: Physicochemical and Engineering Aspect, 73(1993):287-300, Elsevier Science Publishers B.V., Amsterdam 90 ------- SURFACTANT ENHANCED SOLUBILIZATION OF RESIDUAL DODECANE IN SOIL COLUMNS 1. EXPERIMENTAL INVESTIGATION K.D. Pennell, L.M. Abriola and WJ. Weber, Jr. Env. Sci. & Tech., 27(12):2322-2340 EPA-600/J-94-052, NTIS PB 94-137023 SURFACTANT ENHANCED SOLUBILIZATION OF RESIDUAL DODECANE IN SOIL COLUMNS 2. MATHEMATICAL MODELING L.M. Abriola, TJ. Dekker and K.D. Pennell. Env. Sci. & Tech., 27(12):2341-2351 EPA-600/J-04-053, NTIS 94-137015 TESTING BIOREMEDIATION IN THE FIELD J.T. Wilson (Book Chapter) In Situ Bioremediation: When Does It Work?, October 1993, pp. 160-184 EPA-600/A-93-260, NTIS PB 94-114709 A THREE-DIMENSIONAL AIR FLOW MODEL FOR SOIL VENTING: SUPERPOSITION OF ANALYTICAL FUNCTIONS J.S. Cho Jnl. Hazardous Materials, 35:31-51, 1993 EPA-600/J-93-461, NTIS PB 94-112851 1994 ABIOTIC TRANSFORMATION OF CARBON TETRACHLORIDE AT MINERAL SURFACES M. Kriegman-King and M. Reinhard EPA-600/R-94-018, NTIS PB 94-144698 DISTRIBUTION OF AREAL RECHARGE TO A DISCRETE FRACTURE NETWORK (FRACNET) MODEL USING THE ANALYTIC ELEMENT METHOD S.R. Kraemer Oral presentation at Analytic Element Modeling of Groundwater Flow International Conference, Indianapolis, Indiana, April 19-21,1994 EVALUATION OF UNSATURATED/VADOSE ZONE MODELS FOR SUPERFUND SITES D.L. Nofziger, J. Chen, and C.T. Harm EPA/600/R-93-184 AN EXPERIMENTAL STUDY OF COMPLETE DISSOLUTION OF A NONAQUEOUS PHASE LIQUID IN SATURATED POROUS MEDIA P.T. Imoff, P.R. Jaffee, and G.F. Finder Water Resources Research, 30(2):307-320, February 1994 FIELD TRAPPING OF SUBSURFACE VAPOR PHASE PETROLEUM HYDROCARBONS E.E. Moyer, D.W. Ostendorf, D.H. Kampbell and Y. Xie GWMR, Winter 1994, pp. 110-119 91 ------- A FULL SCALE FIELD DEMONSTRATION OF THE USE OF HYDROGEN PEROXIDE FOR IN- SITU BIOREMEDIATION OF AN AVIATION GASOLINE-CONTAMINATED AQUIFER J.T. Wilson, J.M. Armstrong, H. Rafai and W.M. Korreck Book Chapter (16), published in Bioremediation: Field Experience. CRC Press, Inc., Lewis Publishers, 1994, pp. 333-359 THE HYDROCARBON SPILL SCREENING MODEL (HSSM), VOLUME 1: USER'S GUIDE J.W. Weaver, R.J. Charbeneau, J.D. Tauxe, B.K. Lien, and J.B. Provost EPA/600/R-94/039a IDENTIFICATION AND COMPILATION OF UNSATURATED/VADOSE ZONE MODELS P.K.M. van der Hiejde EPA/600/R-94/028 A NEW APPROACH TO PURGING MONITORING WELLS R.W. Puls Ground Water Age, 28(5): 18-19 NITRATE-MEDIATED BIODEGRADATTON OF BTEX IN JP-4-CONTAMINATED SOIL AND GROUNDWATER: A FIELD PILOT-SCALE DEMONSTRATION PROJECT W.C. Downs, S.R. Hutchins, J.T. Wilson, R.H. Douglass and D.J. Hendrix Book Chapter (17), published in Bioremediation: Field Experience, Lewis Publishers, 1994, pp. 361-379 *Not Available NTIS A SCREENING MODEL FOR NONAQUEOUS PHASE LIQUID TRANSPORT IN THE VADOSE ZONE USING GREEN-AMPT AND KINEMATIC WAVE THEORY J.W. Weaver, R.J. Charbeneau, and B.K. Lien Water Resources Research, 30(1):93-105 USE OF CATIONIC SURFACTANTS TO MODIFY SOIL SURFACE TO PROMOTE SORPTION AND RETARD MIGRATION OF HYDROPHOBIC ORGANIC COMPOUNDS J. Wagner, H. Chen, BJ. Brownawell and J. Westall Environ. Sci. & Tech., 28(2):231-237, 1994 92 {lU.S. GOVERNMENT PRINTING OFFICE: 1994 - 550-001/80406 ------- |