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The methodology, case-study examples, and recommendations described in this report are intended to provide restoration program managers, their support staff, and the regulatory community with descriptions of methods and tools that can be used to advance the state-of-practice for monitoring and documenting the long-term sustainability of monitored natural attenuation (MNA)-based remedies for chlorinated solvent-impacted groundwater. Specifically, this report 1) presents a strategy and framework for quantitatively assessing the sustainability of MNA-based remedies for groundwater at chlorinated solvent-impacted sites, 2) provides case-study reviews using existing long-term monitoring (LTM) data sets from multiple United States Air Force sites where chlorinated solvents exceed closure criteria, and 3) summarizes observations and recommendations that were developed when working through the case-study examples., Task order no. 0024.

This update report presents the results or work completed to evaluate additional analytical data collected to augment the original fuels weathering study performed for AFCEE. The original report, "Light Nonaqueous-Phase Liquid (LNAPL) Weathering at Various Fuel Release Sites" was completed Sep 1999. The existing data set from the original fuels weathering study was augmented with newly-collected data from several additional sites. The expanded data set was used to from a more robust database for estimating fuel LNAPL weathering rates. Both the original study and this update locus primarily on the weathering or natural depletion or STEX components from free-phase product., The original document contains color images.

Subsequent to the initial natural attenuation treatability studies performed from 1994 through 1999 at over 45 sites, update data collected by the National Risk Management Research Laboratory and Base monitoring programs were used to evaluate the correctiveness or natural attenuation at reducing contaminant concentrations in groundwater at 24 selected sites. Discrepancies between observed and predicted contaminant trends and plume behavior suggested that critical model input parameters may be inaccurate; therefore, the influence or natural attenuation processes may not have been accurately simulated. As a result of these observations, this project was initiated to compare model-predicted and observed contaminant trends and to evaluate some fundamental parameters that impact the accuracy of natural attenuation predictions, relative to updated field observations., The original document contains color images.

This report presents the results of an addendum to the Intrinsic Remediation Engineering Evaluation/Cost Analysis (EE/CA) for the Former Aerospace Ground Equipment (AGE) Fueling Facility Site performed by Parsons Engineering Science (Parsons ES) at Seymour-Johnson Air Force Base (AFB), North Carolina (Parsons ES, 1996). The EE/CA was conducted to evaluate the use of intrinsic remediation with long-term monitoring (LTM) to address fuel-hydrocarbon-contaminated groundwater at the AGE Site. This addendum to the EE/CA summarizes the results of a groundwater sampling event conducted in April 2001 by the United States Environmental Protection Agency (US EPA) National Risk Management Research Laboratory (NRMRL) Subsurface Protection Division and Parsons ES. Results of this sampling event are used to evaluate spatial and temporal trends of groundwater contaminants at the AGE Site., The original document contains color images.

This document was written to provide practical guidance on the optimization of soil vapor extraction (SVE) systems to assist Air Force environmental managers and consulting engineers who are responsible for the operation and monitoring of these systems so remediation goals can be achieved in a cost-effective manner. Five primary topics are presented: the importance of accurate site characterization and how new characterization methods can enhance and redefine the conceptual site model and basis of design, the importance of a clear understanding of site closure requirements and defining remediation goals, standard methods for monitoring SVE system performance, common performance problems and methods of improving and optimizing the performance of these systems, and approaches to obtaining site closure.

During this decade, the Department of Defense will spend over one billion dollars per year on the operation, maintenance, and monitoring of environmental remediation system. This document was written to assist Air Force environmental managers and consulting engineers who are responsible for the operation and monitoring of soil vapor extraction (SVE) systems, and to promote the closure of sites where SVE systems have achieved cleanup goals. Practical guidance is provided on performance monitoring and the optimization of SVE systems so that remediation goals can be achieved in a cost-effective manner. This document was prepared by Parsons Engineering Science Inc. under the direction of the Technology Transfer Division of the Air Force Center for Environmental Excellence (Contract No. F116323-94-D-0024, D.O. 39)., The original document contains color images.

This report assesses the degree to which various types or engineered source-reduction efforts at selected fuel-contaminated sites have resulted in decreasing concentrations of fuel constituents dissolved in groundwater. This report also describes a methodology for evaluating the potential effectiveness or source-reduction actions at reducing the magnitude and extent of dissolved fuel constituents., The original document contains color images.

The original document contains color images.

This document compiles the presentations given on January 11, 2000 for the Air Force Center for Environmental Excellence Natural Attenuation Initiative. In addition to opening and closing remarks this document contains the following technical summary reports: Natural Attenuation of Fuel Hydrocarbons -- Performance and Cost Results, Natural Attenuation of Chlorinated Solvents -- Performance and Cost Results, Stream-Lined Risk-Based Natural Attenuation Projects -- Performance and Cost Results, Light Nonaqueous-Phase Liquid Weathering at Various Release Sites -- Source Reduction Effectiveness Technical Summary.

ELECTRONIC FILE CHARACTERISTICS: 109 files; Model Data and Database; Visual MODFLOW, MS Access. PHYSICAL DESCRIPTION: 1 CD-ROM; 4 3/4 in.; 5.43 and 3.4 MB (unzipped files). SYSTEMS DETAIL NOTE: Requires software to unzip files (on diskettes). ABSTRACT: This report presents the results of a treatability study (TS) performed by Parsons Engineering Science, Inc. at LF02, Robins Air Force Base (AFB), Georgia to evaluate the natural attenuation of dissolved chlorinated benzenes in groundwater. This TS is part of a multi-site Air Force Research Laboratory initiative to document the natural atenuation of chlorinated benzene compounds under varied site conditions. Once released to the environment, chlorinated benzenes can exhibit natural attenuation patterns that are similar to those observed for chlorinated aliphatic hydrocarbons (CAHs). However, relatively few natural attenuation field studies for chlorinated benzenes have been performed. The purpose of this study was to increase the understanding of chlorinated benzene attenuation in the environment and to promote the use of monitored natural attenuation (MNA) for chlorinated benzene contaminants at Robins AFB or other Federal installations, as appropriate. The site history suggests that natural attenuation, in conbination with the hydraulic characteristics of the uppermost three aquifers of the site, has been effective, and will continue to be effective in controlling contaminant migration and reducing contaminant mass without additional engineered remediation., Computer diskettes for Appendix D contain data collected in MS Access database; Appendix F contains Model Input files. --Original contains color plates: All DTIC reproductions will be in black and white. Document was originally provided on computer diskette, and was migrated to CD-ROM.

This report was prepared by Parsons Engineering Science, Inc. (Parsons ES) to present the results of a focused Corrective Measures Study (CMS), including an assessment of the potential for remediation by natural attenuation (RNA) of groundwater contaminated with chlorinated aliphatic hydrocarbons (CAHs) (in essence, an RNA treatability study RNA TS), for Site SS-45 at the former England Air Force Base (AFB), Alexandria, Louisiana. As used in this report, RNA refers to a management strategy that relies on the evaluation and application of natural attenuation mechanisms, within the context of a carefully controlled and monitored site cleanup approach, that will reduce contaminant mass and/or concentrations to levels that are protective of human health and the environment, within a reasonable time frame.

This report contains the summary of Hydropunch Groundwater sample results on England AFB, Alexandria, Louisiana. Charts displaying The measurements of volatile organic compounds ares shown. The report recommends natural attenuation with institutional controls as the most cost-effective method for achieving groundwater remedial action goals. This action is appropriate. The report indicates that groundwater contamination plume at each site appears to have stabilized, horizontally and vertically, in a relatively small area from when the disposal practices that caused the groundwater contamination started 30 to 40 years ago. The proposed long-term groundwater monitoring program includes sentry wells to provide assurance of the protectiveness of human health and the environment and trend analysis wells that demonstrates the effectiveness of the natural attenuation process. However, it is suggested that the proposed number of groundwater monitoring wells be reduced.

This slide presentation summarizes the live-year results of natural attenuation treatability studies at 42 Air Force sites contaminated with fuel hydrocarbons. The main emphasis of the work described in this report was to evaluate the potential for naturally occurring degradation mechanisms to reduce dissolved benzene, ethylbenzene, toluene, and xylenes concentrations in groundwater to levels that are protective or human health and the environment., The original document contains color images.

This technical memorandum summarizes the five-year results of natural attenuation treatability studies at 42 Air Force sites contaminated with fuel hydrocarbons. The main emphasis of the work described in this report was to evaluate the potential for naturally occurring degradation mechanisms to reduce dissolved benzene, ethylbenzene, toluene, and xylenes concentrations in groundwater to levels that are protective of human health and the environment.natural attenuation, The original document contains color images.

This slide presentation summarizes the results of natural attenuation treatability studies at 14 Air Force sites contaminated with chlorinated solvents and their associated biodegradation daughter products (chlorinated aliphatic hydrocarbons CAHs) or a mixture of solvents and other contaminants (principally fuels). The main emphasis of the work described in this report was to evaluate the potential for naturally occurring degradation mechanisms to reduce the concentrations of CAHs dissolved in groundwater to levels that are protective of human health and the environment, and to limit the migration of CAH plumes in groundwater., The original document contains color images.

This slide presentation summarizes the results or streamlined, risk-based corrective action (RBCA) assessments performed at nine Air Force sites with fuel-contaminated groundwater. The goal of this risk-based remediation approach was to find the most cost-effective method of reducing current and future potential risk by combining chemical source reduction, chemical migration control, and receptor restriction risk-reduction techniques., The original document contains color images.

This slide presentation summarizes the approach to be followed when evaluating the natural attenuation or MTBE and other fuel oxygenate and considers the consequences or the unique physical and chemical characteristics and their resultant behavior in the environment., The original document contains color images.

This report summarizes the approach to be rollowed when evaluating the natural attenuation or MTBE and other fuel oxygenate and considers the consequences or the unique physical and chemical characteristics and their resultant behavior in the environment., The original document contains color images.

This document summarizes the results or streamlined, risk-based corrective action (RBCA) assessments performed at nine Air Force sites with fuel-contaminated groundwater. The goal of this risk-based remediation approach was to find the most cost-effective method for reducing current and future potential risk by combining chemical source reduction, chemical migration control, and receptor restriction risk-reduction techniques., The original document contains color images.

This technical memorandum summarizes the results of natural attenuation treatability studies (TSs) conducted at 14 United States (US) Air Force sites in the Continental US. In June 1993, the Air Force Center for Environmental Excellence, Technology Transfer Division (AFCEE/ERT), in cooperation with the US Environmental Protection Agency National Risk Management Research Laboratory, Subsurface Protection and Remediation Division, and Parsons Engineering Science, Inc. (Parsons ES), began a major initiative to evaluate the effectiveness of monitored natural attenuation (MNA) for remediation of groundwater contaminated with organic compounds., The original document contains color images.

This slide presentation presents the results or work completed to evaluate analytical data related to fuels weathering (primarily JP-4) . The companion report, "Light Nonaqueous-Phase Liquid (LNAPL) Weathering at Various Fuel Release Sites" was completed Sep 1999. The data set was used to form a robust database for estimating fuel LNAPL weathering rates. The study focused primarily on the weathering or natural depletion or BTEX components from free-phase product., The original document contains color images. Task no. 24. Contains viewgraphs only.

This confirmation sampling and analysis report for Site ST-001, at Gunter Annex, Maxwell Air Force Base (AFB), Alabama has been prepared by Parsons Engineering Science, Inc. (Parsons ES) for submittal, to the Alabama Department of Environmental Management (ADEM); the US Air Force Center for Environmental Excellence (AFCEE), Brooks AFB, Texas; and 42 Civil Engineering Squadron, Environmental Group (CES/CEVR), Maxwell AFB, Alabama. ADEM provides oversight of underground storage tank (UST) work at Gunter Annex. This report has been prepared as part of the AFCEE Extended Bioventing Project (Contract F41624-92-8036, Delivery Order 17). The purpose of this report is to document the effectiveness of soil remediation at Site ST-001 and to demonstrate compliance with ADEM risk-based corrective action (ARBCA) guidance for soil and groundwater for site closure., The original document contains color images.

ELECTRONIC FILE CHARACTERISTICS: 2 zipped files/45 unzipped: MODFLOW data files. PHYSICAL DESCRIPTION: 1 CD-ROM; 4 3/4 in.; 12.2MB (unzipped files). SYSTEMS DETAIL NOTE: IBM-clone PC-compatible; requires pkunzip or WinZip software., See also: ADA381592, hard copy or online version of report, for which this diskette is Appendix F. MODFLOW software: MODular three-dimensional finite-difference ground-water FLOW model. Document was originally provided on computer diskette, and was migrated to CD-ROM.

ELECTRONIC FILE CHARACTERISTICS: 2 zipped file + pkunzip software; 20 unzipped data files. PHYSICAL DESCRIPTION: 1 CD-ROM; 4 3/4 in.; 3.78MB (unzipped files). SYSTEMS DETAIL NOTE: IBM-clone PC-compatible; requires pkunzip (on diskette)., Appendix D contains Bioplume II model input and output in ASCII format. See ADA382789 for hard copy or online version of complete report for which this diskette is Appendix D. Document was originally provided on computer diskette, and was migrated to CD-ROM.

ELECTRONIC FILE CHARACTERISTICS: 2 zipped files/30 data files; MS Excel and MODFLOW model data, figures, plots, and tables; pkunzip software. PHYSICAL DESCRIPTION: 1 CD-ROM; 4 3/4 in. SYSTEMS DETAIL NOTE: IBM-clone PC-compatible; requires pkunzip (on disc)., See also ADA381-6l3 for complete report. This diskette is Appendix E. Document was originally provided on computer diskette, and was migrated to CD-ROM.

ELECTRONIC FILE CHARACTERISTICS: 10 zip files, 73 unzipped; MODFLOW data files. PHYSICAL DESCRIPTION: 1 CD-ROM; 4 3/4 in.; 16.3MB (unzipped files). ABSTRACT: This report presents the results of a remediation by natural attenuation treatability study (RNA TS) performed by Parsons Engineering Science, Inc. (Parsons ES) at Building 301 (B301), Offutt Air Force Base, Nebraska to evaluate the use of natural attenuation with long-term monitoring (LTM) as a remedial option for dissolved chlorinated aliphatic hydrocarbon (CAH) contamination in the surficial water-bearing zone. The presence of groundwater contamination at the site was documented during the remedial investigation performed by Woodward-Clyde Consultants (WCC). This TS focuses on the impact of dissolved CAHs, primarily trichloroethene (TCE), on groundwater and surface water at and downgradient from the site. Site history and the results of soil, groundwater, and surface water investigations conducted previously also are summarized in this report., See also: ADA38613O. Diskette data files in MODFLOW (MODular three-dimensional finite-difference ground-water FLOW model). Document was originally provided on computer diskette, and was migrated to CD-ROM.

ELECTRONIC FILE CHARACTERISTICS: 1 zipped file/4 data files; Model data (ASCII format) and pkunzip software. PHYSICAL DESCRIPTION: 1 CD-ROM; 4 3/4 in.; 3.22MB (unzipped files). ABSTRACT: This report presents the results of a remediation by natural attenuation (RNA) treatability study (TS) performed by Parsons Engineering Science, Inc. (Parsons ES) at the Tank 349 site, Offutt Air Force Base (AFB), Nebraska. The objective of the TS was to evaluate the use of RNA with long-term monitoring (LTM) as a remedial option for dissolved benzene, toluene, ethylbenzene, and xylenes (BTEX) contamination in the shallow saturated zone. The dissolved BTEX plume results from the presence of mobile, light nonaqueous-phase liquid (LNAPL) on the groundwater table and residual LNAPL within the aquifer matrix. This study focused on the impact of mobile LNAPL and dissolved BTEX on the shallow groundwater system at and downgradient from the site. Site history, the physical characteristics of the study area, the results of environmental (soil, groundwater, and LNAPL) sampling, evidence regarding the occurrence of RNA, numerical groundwater fate and transport modeling results, and an evaluation of remedial alternatives also are summarized in this report., Report is accompanied by computer diskette with Appendix E, which contains Bioplume II model input and output in ASCII format. Also prepared for Offutt Air Force Base, Omaha, Nebraska. Document was originally provided on computer diskette, and was migrated to CD-ROM.

ELECTRONIC FILE CHARACTERISTICS: 4 data files in 1 zip file; pkunzip software. PHYSICAL DESCRIPTION: 1 CD-ROM; 4 3/4 in. ABSTRACT: The report (ADA381424) that this diskette accompanies presents the results of a treatability study performed by Parsons Engineering Science Inc. at the Michigan Air National Guard facility at W.K. Kellogg Memorial Airport, Battle Creek, Michigan to evaluate the use of intrinsic remediation (natural attenuation) with long-term monitoring as a remedial option for dissolved benzene, toluene, ethylbenzene and xylene (BTEX) contamination in the shallow saturated zone in the vicinity of the Fire Training Site (Site 3). Soil and groundwater contamination is documented for the site in the report. An important component of the study was an assessment of the potential for BTEX contamination dissolved in groundwater to migrate from the source area to potential receptors. The Bioplume II model was used to estimate the rate and direction of dissolved BTEX movement through the shallow saturated zone under the influence of advection, dispersion, sorption, and biodegradation. Input parameters for the Bioplume II model were obtained from existing site characterization data, supplemented with data collected by Parsons under this program. Extensive site-specific data were used for model implementation. Model parameters that were not measured at the site were estimated using reasonable literature values. Section 5 of the report provides details on the model code design and assumptions., Diskette contains pkunzip software and a zip file which must be copied to the hard drive before unzipping the four data files. Document was originally provided on computer diskette, and was migrated to CD-ROM.

ELECTRONIC FILE CHARACTERISTICS: 6 Data files; Visual MODFLOW, MT3D. PHYSICAL DESCRIPTION: 1 CD-ROM; 4 3/4 in.; 1.28 MB (uncompressed). SYSTEMS DETAIL NOTE: IBM-clone PC-compatible; requires Pkunzip or Winzip to decompress files. ABSTRACT: This report presents the results of a remediation by natural attenuation treatability study (RNS TS) performed by Parsons Engineering Science, Inc. at Fire Training Area 2 (Site FT004), Randolph AFB, TX. The TS evaluates the use of natural attenuation with long-term monitoring (LTM) as a remedial option for dissolved chlorinated aliphatic hydrocarbon (CAH) and fuel hydrocarbon contamination in groundwater. The presence of groundwater and soil contamination at the site has been documented during previous investigations. Appendix E1 Model Input and Output Files (Computer Diskette) contains the input and output files for each model run in MODFLOW and MT3D files., 1. Use Pkunzip (on diskette) or Winzip to decompress the files on the diskette, which will create the input and output files for each model run in uncompressed ASCII format. 2. Model files generated during decompression are listed in Appendix E. 3. Document was originally provided on computer diskette and was migrated to CD-ROM.

ELECTRONIC FILE CHARACTERISTICS: 11 files; ascii format. PHYSICAL DESCRIPTION: 1 CD-ROM; 4 3/4 in.; 2.5 MB (unzipped). SYSTEMS DETAIL NOTE: IBM-clone PC-compatible. ABSTRACT: The intent of this Engineering Evaluation/Cost Analysis (EE/CA) was to determine the role of natural attenuation in remediating fuel contamination in groundwater at FPTA No. 4. The report presents the results of an investigation to evaluated the use of intrinsic remediation (natural attenuation) with long-term monitoring (LTM) as a remedial option for dissolved benzene, toluene, ethylbenzene, and total xylenes (BTEX) contamination at the former Fire Protection Area (FPTA) No. 4. Parsons conducted field investigations at this site in May of 1995. Previous investigations have determined that jet fuel (JP-4) and chlorinated solvents had been released into the soil and shallow groundwater at the site due to open burning of waste fuels during fire training exercises., Report (various pagings, ill., foldouts) with 2 Computer diskettes. Appendix E: Intrinsic Remediation EE/CA Pope AFB FPTA-4 - Disk 1, Model Calibration Files in Excel Format, and Disk 2, Model Input and Output Files in ASCII Format. Contains Foldouts. Document was originally provided on computer diskette, and was migrated to CD-ROM.

ELECTRONIC FILE CHARACTERISTICS: 1 zipped file/8 files unzipped; data in ASCII format. PHYSICAL DESCRIPTION: 1 CD-ROM; 4 3/4 in.; 1MB (unzipped files). SYSTEMS DETAIL NOTE: Requires pkunzip software to unzip files (on disc)., See also ADA38l423, full text version of report in hardcopy and online. The diskette is Appendix D for the report (351 p., ill.) which it accompanies. Document was originally provided on computer diskette, and was migrated to CD-ROM.

ELECTRONIC FILE CHARACTERISTICS: 1 zip file with unzip software; data files in ASCII format (unzipped). PHYSICAL DESCRIPTION: 1 CD-ROM; 4 3/4 in.; 1.57MB (unzipped files). SYSTEMS DETAIL NOTE: IBM-clone PC-compatible., Appendix D contains Bioplume II model input and output in ASCII format on diskette. Copy zipped file to hard drive before unzipping. See also ADA381423, hard copy and online version of report. Document was originally provided on computer diskette, and was migrated to CD-ROM.

ELECTRONIC FILE CHARACTERISTICS: Software in MS Excel. PHYSICAL DESCRIPTION: 1 CD-ROM; 4 3/4 in.; 326 KB. SYSTEMS DETAIL NOTE: IBM-clone PC-compatible. ABSTRACT: BIOSCREEN is a public-domain, screening-level computer model, which can be used to simulate remediation of dissolved hydrocarbons at petroleum release sites due to natural attenuation. The software consists of a Microsoft (R) Excel spreadsheet based on an implementation of the Domenico (1987) analytical solute transport model. The model can simulate the processes of advection, dispersion, adsorption, first-order decay reactions, and aerobic and anaerobic instantaneous decay reactions. Appendix E on diskette accompanies report, available online or in hard copy: see also ADA 381-891., Appendix E contains BIOSCREEN model input and output files on computer diskette. Software displays on MS Excel 4.0; macros cannot be disabled and used to fully display model data. More details on the BIOSCREEN model software are in Section 5 of the report. Document was originally provided on computer diskette, and was migrated to CD-ROM.

ELECTRONIC FILE CHARACTERISTICS: 20 zipped files in 1 WinZip folder; text and MS Excel. PHYSICAL DESCRIPTION: 1 CD-ROM; 4 3/4 in. SYSTEMS DETAIL NOTE: IBM-clone PC-compatible. ABSTRACT: This report presents the results of a treatability study (TS) performed by Parsons Engineering Science, Inc. (Parsons ES) at Site S-1, Zone 5 at Kelly Air Force Base (AFB), Texas to evaluate natural attenuation of dissolved chlorinated benzenes in groundwater. The TS focused on the fate and transport of dissolved chlorinated benzenes, which are present at high concentrations at the site. Other contarninants detected at the site (fuel hydrocarbons and chlorinated ethenes) were present at lower concentrations, and the evaluation of their significance was limited to their influence on the natural attenuation of chlorinated benzenes. The site history and the results of the soil and groundwater investigations conducted previous to this TS also are summarized and evaluated in this report. Groundwater data indicate that 1 ,2,4-trichlorobenzene, dichlorobenzene, trichloroethene, and dichloroethene are being reductively dechlorinated at the site through the microbial use of natural organic carbon and groundwater contaminants as substrates. Groundwater is highly reduced in the source area and contaminants known to be susceptible to reductive dechlorination processes generally are being degraded., This diskette is one of two appendixes on removable media to hard copy report (ADA 366-946). Document was originally provided on computer diskette, and was migrated to CD-ROM.

ELECTRONIC FILE CHARACTERISTICS: 90 files (unzipped) in 3 WinZip folders. PHYSICAL DESCRIPTION: 1 CD-ROM; 4 3/4 in. SYSTEMS DETAIL NOTE: IBM-clone PC-compatible. ABSTRACT: This report presents the results of a treatability study (TS) performed by Parsons Engineering Science, Inc. (Parsons ES) at Site S-1, Zone 5 at Kelly Air Force Base (AFB), Texas to evaluate natural attenuation of dissolved chlorinated benzenes in groundwater. The TS focused on the fate and transport of dissolved chlorinated benzenes, which are present at high concentrations at the site. Other contaminants detected at the site (fuel hydrocarbons and chlorinated ethenes) were present at lower concentrations, and the evaluation of their significance was limited to their influence on the natural attenuation of chlorinated benzenes. The site history and the results of the soil and groundwater investigations conducted previous to this TS also are summarized and evaluated in this report. Groundwater data indicate that 1,2,4-trichlorobenzene, dichlorobenzene, trichloroethene, and dichioroethene are being reductively dechlorinated at the site through the microbial use of natural organic carbon and groundwater contaminants as substrates. Groundwater is highly reduced in the source area and contaminants known to be susceptible to reductive dechlorination processes generally are being degraded., Diskette is one of two appendixes on removable media to hard copy report (ADA 366-946). BIOPLUME III can be downloaded from the following EPA web site: http://www.epa.gov/ada/csmos/models/bioplume3.html. Document was originally provided on computer diskette, and was migrated to CD-ROM.

ELECTRONIC FILE CHARACTERISTICS: 184 files; zipped MODFLOW files and pkunzip software. PHYSICAL DESCRIPTION: 1 CD-ROM; 4 3/4 in.; 963 KB (unzipped files). SYSTEMS DETAIL NOTE: IBM-clone PC-compatible. ABSTRACT: This diskette is Appendix E for the report, which presents the results of a remediation by natural attenuation treatability study (RNA TS) performed by Parsons Engineering Science, Inc. (Parsons ES) at Operable Unit I (OU-I), Landfill 4 (LF-04), Altus Air Force Base, Oklahoma to evaluate the use of natural attenuation with long-term monitoring (LTM) as a remedial option for dissolved chlorinated aliphatic hydrocarbon (CAH) contamination in the surficial water-bearing zone. The presence of groundwater contamination at the site was documented during the remedial investigation performed by the United States Geological Survey (USGS, 1996). This TS focused on the impact of dissolved CAHs on groundwater and surface water at and downgradient from the site. Site history and the results of soil, groundwater, and surface water investigations conducted previously also are summarized in this report. The diskette contains the MODFLOW and Model lnputlOutput files and Slug test files., Appendix E: Model Input and Output Files (Computer Diskette) contains the input and output files for each model run in MODFLOW and MT3D files. See also: ADA381-497. Diskette data files in MODFLOW (MODular three-dimensional finite-difference ground-water FLOW model). Document was originally provided on computer diskette, and was migrated to CD-ROM.

This report presents the results of a remediation by natural attenuation treatability study (RNA TS) performed by Parsons Engineering Science, Inc. (Parsons ES) at Fire Training Area 2 (FTA-2), Tinker Air Force Base (AFB), Oklahoma. The RNA TS was performed to evaluate the use of natural attenuation with long-term monitoring (LTM) as a remedial option for dissolved chlorinated aliphatic hydrocarbon (CAM) contamination in the upper saturated zone (USZ). The presence of groundwater contamination and soil contamination at the site was documented during remedial investigations performed by International Technology Corporation (IT) (1994) and Tetra Tech (TT) (1996). This TS focused on the impact of dissolved CAHs, primarily trichloroethane (TCE), on the USZ groundwater system at, and downgradient from, the site. Site history and the results of soil and groundwater investigations conducted previously also are summarized in this report., Original contains color plates: All DTIC reproductions will be in black and white.

This report presents the results of a treatability study (TS) performed by Parsons Engineering Science, Inc. (Parsons ES) at Operable Unit 4 (OU-4) at Shaw Air Force Base, South Carolina, to evaluate remediation by natural attenuation (RNA) of dissolved chlorinated aliphatic hydrocarbons (CAHs) and fuel hydrocarbons in groundwater. The TS focused on the fate and transport of dissolved CAHs, particularly 1,1, 1-trichloroethane (1,1, 1-TCA), which is present at high concentrations at the site. Petroleum hydrocarbons INCLUDING BENZENE, TOLUENE, ETHYLBENZENE, AND XYLENES (BTEX) also are present in site groundwater and were considered in this TS. The site history and the results of the soil and groundwater investigations conducted previously also are summarized in this report.

This report presents the results of a treatability study (TS) performed by Parsons Engineering Science, Inc. (Parsons ES) at the Area A Service Station (Area A), Tinker Air Force Base (AFB), Oklahoma, to evaluate remediation by natural attenuation (RNA) of dissolved chlorinated aliphatic hydrocarbons (CAHs) and fuel hydrocarbons in groundwater. The TS focused on the fate and transport of dissolved CAHs, particularly trichloroethene (TCE), which are present at high concentrations. Petroleum hydrocarbons INCLUDING BENZENE, TOLUENE, ETHYLBENZENE, AND XYLENES (BTEX) are also present in site groundwater and were considered in this TS. The site history and results of previous soil and groundwater investigations are also summarized in this report., Original contains color plates: All DTIC reproductions will be in black and white.

ELECTRONIC FILE CHARACTERISTICS: 264 files; Text, tables, figures and drawings; MS Word, MS Excel, AutoCad. PHYSICAL DESCRIPTION: 1 computer laser optical disc (CD-ROM); 4 3/4 in.; 107MB. SYSTEMS DETAIL NOTE: Requires unzip utility to open files in /Models folder. ABSTRACT: This report presents the results of a treatability study (TS) conducted to evaluate the use of natural attenuation for remediation of chlorinated aliphatic hydrocarbon (CAM) - contaminated groundwater at Site LF-03, F. E. Warren AFB, Wyoming. The numerical models MODFLOW and MT3D were used in conjunction with site-specific geologic, hydrologic, and laboratory analytical data to simulate the migration and biodegradation of trichloroethene (TCE) dissolved in groundwater. It is likely that contaminants were first introduced into groundwater at this site shortly after the opening of LF-03 around 1960. Solvents, fuels, and other liquid wastes may have been spilled or dumped, or have leaked from containers in the landfill. Contaminants dissolved in leachate are assumed to have entered groundwater over relatively large areas (i.e., the landfill), through point sources due to spills or dumping, or through contact between groundwater and residual non-aqueous phase liquid (NAPL) at or below the water table. Contaminants observed in groundwater at LF-03 at concentrations greater than US Environmental Protection Agency (USEPA) maximum contaminant levels (MCLs) include TCE and cis-1,2-dichloroethene (cis- 1,2-DCE). The dissolved CAM plume - appears to have migrated approximately 1,500 feet northeast from the source area at LF-03. Comparison of TCE plumes delineated in 1993 and 1999 indicate that the TCE plume is stable, although TCE concentrations have increased at several locations within the plume. This disc contains all of the original report files, drawings and models, including color illustrations, assembled into the paper version of the report., See also ADA381632, paper version of report.

This report incorporates comments received from Mr. Bruce Moore of the MDEQ and Ms. Laura Ripley of the USEPA on the draft final confirmation sampling and analysis report. Wurtsmith AFBCA and AFCEE/ERT had no comments on the draft final report. This report represents the final contract deliverable for the AFCEE Extended Bioventing Project at the Wurtsmith AFB POL Yard. If you have any questions or comments regarding this package, please call John Hall at (970) 244-8829, or me at (303) 831-8100.

This confirmation sampling and analysis report for Installation Restoration Program (IRP) Site SD-11, Aircraft Ground Equipment (AGE) Maintenance Area at Beale Air Force Base (AFB), California has been prepared by Parsons Engineering Science, Inc. (Parsons ES; formerly Engineering-Science, Inc. ES) for submittal to the California Regional Water Quality Control Board (RWQCB), Central Valley Region; the US Air Force Center for Environmental Excellence (AFCEE), Brooks AFB, Texas; and the 9th Civil Engineering Squadron, Environmental Flight (9 CES/CEV) Beale AFB, California. This report has been prepared as part of the AFCEE Extended Bioventing Project (Contract F41624-92-8036, Delivery Order 17). The purposes of this report are to provide the results of the confirmation soil and soil vapor sampling performed at the site in January 1999, and to evaluate the effectiveness of implemented soil remediation at the site.

This report presents the results of a treatability study performed by Parsons Engineering Science, Inc. (Parsons ES) at Fire Protection Training Area 3 (FPTA3), Offutt Air Force Base, Nebraska to evaluate the use of intrinsic remediation (natural attenuation) with long-term monitoring (LTM) as a remedial option for dissolved benzene, toluene, ethylbenzene, and xylene (BTEX) contamination in the shallow groundwater. Residual light nonaqueous-phase liquid (LNAPL) is present within the soil and dissolved contamination is present in the groundwater. There is no evidence of mobile LNAPL (free product) at this site. This study focused on the impact of dissolved BTEX on the shallow groundwater system at the site. Dissolved chlorinated solvents also are present in the shallow groundwater; therefore, the impact of the dissolved chlorinated solvents was studied as well. Site history and the results of soil and groundwater investigations conducted previously are also summarized in this report.

This report presents the results of a treatability study for remediation by natural attenuation (RNA TS), completed by Parsons Engineering Science, Inc. (Parsons ES) at IRP Site SS-04, Langley Air Force Base (AFB),Virginia. The TS evaluates the use of natural attenuation with long-term monitoring (LTM) as a remedial option for dissolved hydrocarbon fuel constituents in groundwater. The occurrence of groundwater and soil contamination at the site, as a consequence of leakage of petroleum-based fuel (jet fuel or JP-4), has been documented during previous investigations. This TS focuses primarily on the impact of dissolved fuel constituents, in particular benzene, toluene, ethylbenzene, and xylene isomers (BTEX), in the groundwater system at, and downgradient from, the source area. Residual fuel hydrocarbon contamination in soil surrounding the source area (the abandoned USTs) was remediated from 1992 through 1996 with a vapor extraction system. The site history and the results of previously- completed soil and groundwater investigations are summarized in this report. Soil and groundwater samples were collected from the site and analyzed to obtain the information necessary for the transport evaluation and RNA demonstration. Physical and chemical data collected under this program were supplemented (where necessary) with data collected during previous site characterization investigations and monitoring events. Biodegradation of fuel hydrocarbons can occur when an indigenous population of hydrocarbon-degrading microorganisms is present in the subsurface, and sufficient concentrations of electron acceptors, nutrients, and electron donors (including fuel hydrocarbons) are available to these organisms. Several lines of chemical and geochemical evidence indicate that dissolved BTEX constituents are undergoing biodegradation within and downgradient from the contaminant source area.

This report presents the results of a treatability study (TS) performed by Parsons Engineering Science, Inc. (Parsons ES) at Facility 1381 (SWMU 21), Cape Canaveral Air Station (CCAS), Florida to evaluate remediation by natural attenuation (RNA) of chlorinated aliphatic hydrocarbons (CAHs) dissolved in the site groundwater. The TS focuses on the fate and transport of dissolved CAHs, particularly trichloroethene (TCE), dichloroethene (DCE), and vinyl chloride (VC). The exact location of residual non-aqueous phase liquid (NAPL) or sorbed solvents in the vadose and/or phreatic soils remains unknown, but nonetheless serves as a continuing source for the currently observed CAH plume. Site history and the results of previous investigations are summarized in this report. The use of RNA with LTM discussed in this report is intended to support remedial alternatives for Facility 1381. Comparison of CAH, electron acceptor, and biodegradation byproduct isopleth maps for Facility 1381 provides strong qualitative evidence for the biodegradation of dissolved CAHs. These geochemical data strongly suggest that reductive dehalogenation of dissolved CAHs is occurring at the site as microbes utilize natural organic carbon as a substrate. Low-level BTEX compounds have been detected in the source area and suggest previous low-level fuel releases or large releases that have since been naturally attenuated; however, current BTEX levels are too low to be a significant substrate source. Patterns observed in the distribution of CAHs, daughter products of CAHs, electron acceptors, and biodegradation byproducts further indicate that biodegradation is reducing the concentration of CAHs dissolved in site groundwater. Field-scale first-order dehalogenation rates of 0.000001/day to 0.00032/day (equivalent to half-lives of 5.9 to 1,900 years) were calculated using site-specific CAH data.

This report presents the results of a treatability study (TS) conducted to evaluate the use of natural attenuation for remediation of chlorinated aliphatic hydrocarbon (CAM) - contaminated groundwater at Site LF-03, F. E. Warren AFB, Wyoming. The numerical models MODFLOW and MT3D were used in conjunction with site-specific geologic, hydrologic, and laboratory analytical data to simulate the migration and biodegradation of trichloroethene (TCE) dissolved in groundwater. It is likely that contaminants were first introduced into groundwater at this site shortly after the opening of LF-03 around 1960. Solvents, fuels, and other liquid wastes may have been spilled or dumped, or have leaked from containers in the landfill. Contaminants dissolved in leachate are assumed to have entered groundwater over relatively large areas (i.e., the landfill), through point sources due to spills or dumping, or through contact between groundwater and residual non-aqueous phase liquid (NAPL) at or below the water table. Contaminants observed in groundwater at LF-03 at concentrations greater than US Environmental Protection Agency (USEPA) maximum contaminant levels (MCLs) include TCE and cis-1,2-dichloroethene (cis-1,2-DCE). The dissolved CAM plume - appears to have migrated approximately 1,500 feet northeast from the source area at LF-03. Comparison of TCE plumes delineated in 1993 and 1999 indicate that the TCE plume is stable, although TCE concentrations have increased at several locations within the plume.

The purpose of this report is to document the effectiveness of soil remediation at SA 6 and to provide data to support an NFI decision for the site. SA 6 is located in the southwestern portion of the base within Operable Unit B (OU B) (Figure 1.1), south of Building 656, and west of Building 655 (Figure 1.2). The site is the former location of a gasoline service station (Building 657) and its associated underground storage tanks (USTs) which were located immediately east of the former building. The site is currently near the center of a large, paved parking lot. The former service station operated from 1955 until 1990. The two gasoline USTs and twO diesel USTs which supplied the station were removed in 1990 and 1991. Initial investigations conducted by the Base determined that the USTs had leaked and contaminated the soil. Subsequent investigations conducted at SA 6 identified fuel hydrocarbons, volatile organic compounds (VOCs) including benzene, toluene, ethylbenzene, and xylenes (BTEX), and halogenated VOCs in soil, soil vapor, and groundwater (ES, 1994; Radian, 1995). Although halogenated VOCs (chlorinated compounds) have been detected at SA 6, the Remedial Investigation Characterization Summary (RICS) (Radian, 1995) concluded that the source of these compounds is Investigation Cluster 7 (IC 7), another OU B site northwest of SA 6. Because only petroleum hydrocarbon contamination is attributed to the former gasoline service station, the RICS concluded that only total petroleum hydrocarbons (TPH) and BTEX were contaminants of potential concern (COPCs) at SA 6.

This report presents the results of a treatability study performed by Parsons Engineering Science. Inc. (Parsons ES) at UST Sites 10-494, 10-495, and 10-496 (UST Site) Beale Air Force Base. California to evaluate the use of remediation by natural attlenuation (RNA) with long-term monitoring (LTM) as a remedial option for dissolved benzene. toluene. ethylbenzene, and xylene (BTEX) and total petroleum hydrocarbons as gasoline (TPH-g) contamination in the shallow groundwater. This study focused on the impact of dissolved BTEX and TPH-g compounds on the shallow groundwater system at the site. Site history and the results of soil and groundwater investigations conducted previously are also summarized in this report.