Open-Path FTIR Air Monitoring of Phosphine Around Large Fumigated Structures
Thorn, T.G., Jr. (Lorillard Tobacco Company, Danville, VA); Timothy L. Marshall (AeroSurvey, Inc., Manhattan, KS); Charles T. Chaffin Jr.
Field Analytical Chemistry & Technology, Vol 5 No 3, p 116-120, Jul 2001

Phosphine concentrations in the air surrounding large fumigated structures at a tobacco storage facility were measured using an open-path Fourier transform infrared (FTIR) spectrometer system to provide comprehensive data, more data than could be obtained with multiple single-point detection devices. Open-path FTIR was employed to more completely characterize phosphine concentrations over long path lengths using a single FTIR. This paper describes the successful result of the application.

Portable Double-Focusing Mass-Spectrometer System for Field Gas Monitoring
Diaz, Jorge A. (Univ. de Costa Rica, San Jose); Clayton F. Giese (Univ. of Minnesota, Minneapolis); W. Ronald Gentry (Univ. of Minnesota, Minneapolis).
Field Analytical Chemistry & Technology, Vol 5 No 3, p 156-167, Jul 2001

A portable mass-spectrometry (MS) device based on a miniature double-focusing sector-field mass spectrometer has been developed for in situ gas analysis and monitoring applications. Able to detect atmospheric species at the part-per-million (ppm) level, the 18-pound device--the Portable-CDFMS--uses a 1.1-Tesla NdFeB permanent magnet, a lithographically defined electric sector, a molecular-flow frit inlet, a spiral filament in a closed ion source, and a miniature channeltron detector. The high vacuum is provided with the use of a very compact hybrid turbomolecular and diaphragm pump combination.

In-Water Field Analytical Technology: Underwater Mass Spectrometry, Mobile Robots, and Remote Intelligence for Wide and Local Area Chemical Profiling
Fries, D.P.; R.T. Short; L.L. Langebrake; J.T. Patten; M.L. Kerr; G. Kibelka; D.C. Burwell; J.C. Jalbert, Univ. of South Florida, St. Petersburg.
Field Analytical Chemistry & Technology, Vol 5 No 3, p 121-130, Jul 2001

The authors describe the operation of chemoreceptive field underwater robots during two field trials, one using numerical models to aid in characterization of chemical dispersion, and the other discriminating a chemical gradient in the field.

Environmental Applications of Thermal Extraction Cone Penetrometry and Ultrafast Gas Chromatography/Mass Spectrometry
Albert Robbat, Albert, Jr., Center for Field Analytical Studies and Technology, Tufts Univ., Medford, MA.
Field Analytical Chemistry & Technology, Vol 5 No 1-2, p 60-68, May 2001

Organic contaminants can be collected and analyzed at depth without bringing soil to the surface. A thermal extraction cone penetrometer (TECP) probe was used to extract soil-bound semivolatile organics, transferring them to the surface for analysis by ultrafast gas chromatography/mass spectrometry (GC/MS). When the soil-water content was <20%, PCBs, PAHs, chlorinated pesticides, and explosives could be collected and analyzed in five minutes, and in 15 minutes with soil-water content between 20 and 35%. When the TECP was directly connected to the GC/MS, TNT and four of its synthetic precursors were speciated in 20 seconds. This project is sponsored by U.S. EPA under the NCERQA program.

Design of Continuous-Monitoring Device Based on Membrane Extraction with Sorbent Interface and Micro-Gas Chromatograph
Ciucanu, Ionel; Janusz Pawliszyn, Dept. of Chemistry, Univ. of Waterloo, Waterloo, Ontario.
Field Analytical Chemistry & Technology, Vol 5 No 1-2, p 69-74, May 2001

This paper describes a device for the continuous monitoring of the volatile and semivolatile organic compounds in air by membrane extraction, followed by sorbent concentration and gas chromatographic separation. The device samples headspace and makes automatic injections, followed by rapid separation and quantification. A membrane module, microtrap, and fan mounted in a housing form a membrane-extraction sorbent interface (MESI) sampling unit. A heated silicosteel capillary column was used as the transfer line. The device shows potential for monitoring aromatic hydrocarbons, chlorinated compounds, and terpenoids in the field.

Fast GC Instrumentation and Analysis for Field Applications
Overton, E.B.; K.R. Carney; Ned Roques; H.P. Dharmasena, Inst. for Environmental Studies, Louisiana State Univ., Baton Rouge.
Field Analytical Chemistry & Technology, Vol 5 No 1-2, p 97-105, May 2001

This paper describes a small, fast, dual-high-resolution-column GC instrument that is capable of analyzing both volatile and semivolatile analytes. The device uses two narrow-bore, 100-micron ID separation columns, is temperature programmable at rates of 5-20°C per second, and uses less than 150 W of dc power. Typical separation times for compounds with Kovatt's retention indices of <1000 are 10-15 s, and compounds with retention indices of up to 2500 are separated in <1min. Analytes are simultaneously analyzed on columns with different liquid phases because of the dual-columns-and-detectors design, thus providing added confidence in the quality of the analytical data. This fieldable GC device can analyze a wide variety of sample matrices, including gases, dilute gases, thermal extracts from VOS tubes, purge-and-trap water/soil extracts, headspace samples, membrane extracts, SPME, thermal and SCF extracts, liquid organic solvent extracts, and direct aqueous samples.

A Cellular Biosensor to Detect Chlorocatechols
Avakian, Maureen D., NIEHS compiler.
NIEHS Research Brief 79, 3 Jul 2001

Scientists at the University of Kentucky (UK) have developed a cellular biosensor system to identify and quantify 3-chlorocatechol and 4-chlorocatechol, toxic breakdown products of PCBs. A biosensor is a biological monitor that recognizes a chemical or physical change and produces a measurable signal in response to the environmental change. Cellular biosensors can be designed for high sensitivity and selectivity, but the greatest advantage of cellular systems is they are capable of measuring the bioavailability of the compound being studied. Cellular biosensor systems operate as follows: the compound being studied passes through the cell membrane; the compound binds to a regulatory protein; the regulatory protein activates a promoter; the promoter activates the reporter gene; translation of the reporter gene produces a reporter protein; and upon addition of an external substrate, the reporter protein produces a measurable signal. To detect 3-chlorocatechol and 4-chlorocatechol, the UK researchers applied genetic engineering techniques to design and develop a cellular biosensor system using the bacteria Pseudomonas putida. These bacteria can use chlorocatechols as a carbon source, biodegrading chlorocatechols via a degradative pathway regulated by the ClcR protein. The UK researchers introduced a plasmid that contains the lacZ gene into P. putida. The lacZ gene is also controlled by the ClcR protein and encodes for b-galactosidase. The researchers verified that the system is extremely specific. They exposed the biosensor system to a series of organic compounds (catechols, chlorophenols, biphenyl) that are structurally related to chlorocatechols and might interfere with the biosensor system. No appreciable levels of b-galactosidase were produced. The UK scientists have also demonstrated that the system is capable of distinguishing 3-chlorocatechol from 4-chlorocatechol. This biosensor system is a probe tailor-made to directly monitor the level of chlorocatechols in soil, sediment, and water samples at Superfund sites. Because it does not require expensive equipment or extensive pretreatment of environmental samples, the UK biosensor system is simpler and more economical than standard methods. The UK scientists are working to develop additional biosensor systems. By using different reporter proteins that emit fluorescence or bioluminescence at different wavelengths, they are developing array sensing systems for a variety of environmental pollutants. Analysis of the color of the light generated by the bacteria will allow for identification of the pollutant(s) present in a particular environment. This would provide tools for in situ monitoring of multiple contaminants at Superfund sites. Contact: Sylvia Daunert, Dept. of Chemistry, Univ of Kentucky, Lexington, (859) 257-7060, daunert@pop.uky.edu

3-D Seismic Tomography Survey at a Groundwater Contamination Site
Azaria, A.; C.A. Zelt; A. Levander; D. Dana; I. Morozov; B. Magnani, Rice Univ., Center for Computational Geophysics, Houston, TX.
Eos Trans. AGU, 81 (48), Fall Meet. Suppl., Abstract S72A-04, 2000

As part of an ongoing environmental characterization project at Hill Air Force Base near Ogden, Utah, a 3-D seismic survey was performed over a contaminated aquifer in July and August 2000. The site contains significant amounts of dense non-aqueous phase liquids (DNAPLs) in a shallow aquifer less than ~15 meters deep. The aquifer is bounded below by a clay aquiclude, in which a paleochannel acts as a trap for the contaminants. The overburden consists of Quaternary sands, gravels and clays. Imaging the structure of the paleochannel at depths up to 15 meters was the main target of the survey. The experiment included 3-D reflection, 3-D refraction, checkshot surveys, and vertical seismic profiles in wells up to 15 meters deep. Preliminary traveltime tomography results from the 3-D tomography and reflection surveys are presented. The results of a 2-D pilot survey conducted in 1998 show that velocity in the near surface increases by almost an order of magnitude in the upper 15 m at this site, from about 200 m/s to 1500 m/s. 3-D synthetic tests were developed using the 2-D results to design the field acquisition program. For the tomography experiment, the entire site (approximately 95 meters by 36 meters in area) was surveyed with about 600 RefTek Texan recorders deployed in a stationary rectangular grid having an inline spacing of 2.8 m and a crossline spacing of 2.1 m. A shot from a .223 caliber rifle was fired at each receiver station, yielding a dataset with about 360,000 traces, and offsets up to 100 m. The source provides a broad frequency range from 40 Hz to greater than 300Hz. The 2-D data and the synthetic tests suggest that the 3-D wide-angle data will provide a well-resolved 3-D velocity model of the paleochannel using first-arrival tomography.

High Resolution 3-D Seismic Investigations at a Groundwater Contamination Site
Dana, D.; A. Levander; I. Morozov; C. Zelt; B. Magnani, Rice Univ., Center for Computational Geophysics, Houston, TX.
Eos Trans. AGU, 81 (48), Fall Meet. Suppl., Abstract S72A-03, 2000

In July and August 2000, the researchers conducted 3-D reflection, tomography, and downhole seismic studies at Operable Unit 2 (OU2) at Hill Air Force Base in Ogden, Utah, where dense nonaqueous phase liquids (DNAPLs) contaminate a shallow (less than 20 m) aquifer. The survey target is a paleochannel buried beneath Quaternary sands, gravels and clays that acts as a local trap for contaminants. The highly irregular, steep walled paleochannel was imaged by a pilot 2-D survey conducted in 1998, demonstrating the viability of seismic methods for investigating the upper 20m at this site. The four week experiment included 3-D seismic reflection, 3-D tomography, six check shot surveys in 15m boreholes for velocity estimation, and two vertical seismic profiles. A 223 rifle was used as the seismic source in all experiments, producing frequencies from 40Hz to greater than 300Hz. Approximately 6000 shot records were taken in the various experiments; the experiment at times generated 9Gbytes of data per day. The 3-D reflection and tomography experiments both occupied an area of 95m by 36m, and utilized over 600 RefTek Texan instruments. For the reflection experiment the instruments were deployed in swaths of six receiver lines 2.1m apart, with geophone intervals in the inline direction of 0.35m. The shot pattern was a rotated brick pattern with 0.35m shot intervals in the inline and crossline directions, producing a nominal 52-fold survey. Data quality appears to be excellent, despite a high level of cultural noise. The shot gathers show strong reflections with conflicting dips, characteristic of steeply dipping features.

A Hybrid Hydrologic-Geophysical Inverse Technique for the Assessment and Monitoring of Leachates in the Vadose Zone
Brainard, J.R. (Sandia National Laboratories, Albuquerque, NM); D.L. Alumbaugh (Univ. of Wisconsin Madison); R.J. Glass (Sandia National Laboratories, Albuquerque, NM); D. Labrecque (Multi-Phase Technologies LLC, Sparks, NV); J. Yeh (Univ. of Arizona, Tucson).
Eos Trans. AGU, Vol 81 No 48, Fall Meet. Suppl., Abstract H22C-10, 2000

During cleanup or immobilization of vadose zone contamination that has occurred through free release of wastes on the surface or by leaking landfills and storage tanks, new and innovative long-term vadose zone monitoring techniques are needed to track hydrologic conditions and provide information on important flow and transport processes. The researchers have focused on developing, implementing, and testing a new approach that synthesizes a recently developed inverse hydrologic modeling technique with state-of-the-art geophysical sensing technologies. The result is a robust method for characterizing, monitoring, and predicting fluid movement in heterogeneous vadose zones.

Effect of Mass Transfer Rate Limitations on the Use of Partitioning Tracers for the Characterization of DNAPL Micropools in the Subsurface.
Pirestani, K.; P.T. Imhoff, Univ. of Delaware, Civil and Environmental Engineering Dept., Newark.
Eos Trans. AGU, Vol 81 No 48, Fall Meet. Suppl., Abstract H71B-08, 2000

Partitioning tracer tests (PTTs) are an innovative technology used for the detection and subsurface distribution estimation of nonaqueous phase liquids (NAPLs). The PTT involves injecting a tracer pulse of partitioning and nonpartitioning tracers into an aquifer with subsequent measurement of the tracer concentrations in extraction wells. The partitioning tracer is retarded or slowed when it partitions into the NAPL. The amount of retardation is proportional to the saturation of NAPL in the porous media. Column experiments were performed to determine the minimum contact time between tracer solutions and rectangular micropools of trichloroethylene (TCE) for detection of all TCE. Different contact times were achieved by flushing tracer solutions of different volumes with different flushing velocities. The TCE micropools were centimeters in size and reflect the small volumes that may be trapped by textural heterogeneities in some subsurface systems. The length and thickness of the TCE micropools were varied to create different required equilibration times. The results from these experiments were put in dimensionless form and used to explore relationships between the size of NAPL micropool and the necessary contact time between tracer solution and micropool for NAPL detection.

List of Leak Detection Evaluations for UST Systems, 8th Edition
National Work Group on Leak Detection Evaluations (NWGLDE). 311 pp, Mar 2001

This reference manual is for State and EPA regulators, especially inspectors of USTs, knowledgeable UST owners and operators wanting to compare specifications for various leak detection devices, and vendors of UST leak detection systems. This reference manual contains a summary of specifications, based on third-party evaluations, for over 275 systems that detect leaks from USTs and their piping. Each summary provides information on such items as certified detectable leak rate/threshold, test period duration, product applicability, calibration requirements, restrictions on the use of the device, and so on. Although maintained by a work group consisting of State and EPA members, the "List Of Leak Detection Evaluations" is not a list of "approved" leak detection systems. Approval or acceptance of leak detection systems is the responsibility of the implementing agency--in most cases the State environmental agency. More information: http://www.epa.gov/swerust1/pubs/ldlist.htm

Mapping the Norman, Oklahoma Landfill Contaminant Plume Using Electrical Geophysics
Bisdorf, R.J.; J.E. Lucius.
Proceedings of the USGS Toxic Substances Hydrology Program Technical Meeting, 8-12 March 1999, Charleston, SC, Volume 3: Subsurface Contamination from Point Sources
U.S. Geological Survey Water-Resources Investigations Report 99-4018C, p 579-584, 1999

The lateral extent of the electrically conductive portion of the contaminant plume emanating from the Norman Landfill was mapped using electrical geophysical measurements. EM induction and DC resistivity methods measured the apparent electrical resistivity of the subsurface. Both methods show an area of low resistivity indicating poor ground-water quality in the alluvium, presumably due to leachate from the Norman Landfill. This area extends from the southwest side of the main landfill mound toward the Canadian River for no more than about 200 meters. Cross section and depth-slice maps made from the interpretation of the DC resistivity soundings and maps of measured resistivity from the EM measurements illustrate the lateral extent of the landfill contamination and show that the contaminate plume, which is about 9 meters thick, does not appear to extend into the bedrock. The EM induction method proved to be an easy and efficient procedure for rapidly determining the lateral extent of the leachate plume. The DC resistivity method, although more time consuming, provided better vertical resolution of the resistivity distribution.

Spectral Induced Polarization Studies of Mine Dumps near Silverton, Colorado
Campbell, David L.; D.V. Fitterman; R.J. Horton.
Science for Watershed Decisions on Abandoned Mine Lands: Review of Preliminary Results, 4-5 February 1998, Denver, Colorado [Abs.].
U.S. Geological Survey Open-File Report 98-297, p 40, 1998

To help study mechanisms that produce acid mine drainage (AMD), the authors made spectral induced polarization (SIP) measurements at the Mayday and Yukon mine dumps, in a Department of Interior Abandoned Mine Lands study area near Silverton, Colorado. Induced polarization is a geophysical method that has long been used to detect disseminated sulfides, and SIP is a refinement of that method that can characterize electrochemical processes taking place at mineral/pore-water interfaces. At Silverton, SIP measurements were made at intervals of 1.5 meters (m) at the Mayday dump and 3.0 m at the Yukon dump along profiles on the dump faces, investigating to depths of about 5 m below the surface. The study results suggest that the acid waters currently draining from the Mayday mine dump probably result mainly from process(es) involving already-oxidized minerals, rather than from primary oxidation of sulfides at grain surfaces.

Accounting for Cyanide and Its Degradation Products at Three Nevada Gold Mines: Constraints from Stable C- and N-Isotopes
Johnson, Craig A.; David J. Grimes; Robert O. Rye.
U.S. Geological Survey Open-File Report 98-0753, [16 pp], 1998

An understanding of the fate of cyanide (CN-) in mine process waters is important for addressing environmental concerns and for taking steps to minimize reagent costs. The utility of stable isotope methods in identifying cyanide loss pathways has been investigated in case studies at three Nevada gold mines. Freshly prepared barren solutions at the mines have cyanide 15N and 13C values averaging -4% and -36%, respectively, reflecting the nitrogen and carbon sources used by commercial manufacturers, air and natural gas methane. Pregnant solutions returning from ore heaps display small isotopic shifts to lower 15N and 13C values. The shifts are similar to those observed in laboratory experiments where cyanide was progressively precipitated as a cyanometallic compound, and are opposite in sign and much smaller in magnitude than the shifts observed in experiments where HCN was offgassed. Offgassing is inferred to be a minor cyanide loss mechanism in the heap leach operations at the three mines, and precipitation as cyanometallic compounds, and possibly coprecipitation with ferric oxides, is inferred to be an important loss mechanism. Isotopic analysis of dissolved inorganic carbon (DIC) shows that uptake of high d13C air CO2 has been important in many barren and pregnant solutions. However, DIC in reclaim pond waters at all three mines has low 13C values of -28 to -34%, indicating cyanide breakdown either by hydrolysis or by other chemical pathways that break the C-N bond. Isotope mass balance calculations indicate that about 40% of the DIC load in the ponds, at a minimum, was derived from cyanide breakdown. This level of cyanide hydrolysis accounts for 14-100 % of the dissolved inorganic nitrogen species present in the ponds. Overall, isotope data provide quantitative evidence that only minor amounts of cyanide are lost via offgassing and that significant amounts are destroyed via hydrolysis and related pathways. The data also highlight the possibility that significant cyanide may be either retained in the ore heaps or destroyed via other chemical pathways. More information: http://greenwood.cr.usgs.gov/pub/open-file-reports/ofr-98-0753/ofr-98-0753.pdf

Preliminary Materials Mapping in the Oquirrh Mountains Region for the Utah EPA Project Using AVIRIS Data
McDougal, R.R.; R.N. Clark; K.E. Livo; R.F. Kokaly; B.W. Rockwell; J.S. Vance.
Summaries of the 8th Annual JPL Airborne Science Workshop, JPL Publication 99-17, p 297-298, 1998

This paper describes a project that is part of the Utah 1998 EPA-USGS AVIRIS study. The principal elements of this joint investigation include mapping and characterization of surficial minerals, watershed evaluation to better define effects of mineralization and related mining activities, and vegetation studies. More information: http://speclab.cr.usgs.gov/earth.studies/Utah-1/Jpl_pap.wpd.html

pick_xwell: A Program for Interactive Picking of Crosswell Seismic and Radar Data
Ellefsen, K.J.
U.S. Geological Survey Open-File Report 99-0534, 1999

Program 'pick_xwell' is used to interactively pick travel times in crosswell seismic and radar data. In addition, the traces and the travel times can be plotted on the computer screen or printed to a file in postscript format. The program is written in the IDL programming language, and it is executed, in command-line mode, within the IDL program. The IDL program must be run from an X-window terminal that is connected to a computer with the Unix operating system. The data must be in the SU format.

Magnetic Resonance Imaging of Hydrocarbon-Contaminated Porous Media
Pervizpour, M.; S. Pamukcu; Horace Moo-Young, Dept. of Civil and Environmental Engineering, Fritz
Engineering Lab., Lehigh Univ., Bethlehem, PA.
Journal of Computing in Civil Engineering, Vol 13 No 2, p 96-102, Apr 1999

Nuclear magnetic resonance response measurement is a nondestructive and nonintrusive technique that is potentially useful for in situ characterization and mapping of hydrocarbon contamination in the subsurface, including rock. Magnetic resonance measurements of a porous medium allow the determination of necessary parameters to evaluate permeability and porosity of the medium and the type of hydrocarbons present in the pore fluid. This paper presents the results of a preliminary study intended to evaluate the robustness of the magnetic resonance imaging technology using well-characterized laboratory specimens of porous material containing hydrocarbon liquids. The porous materials tested were 1) a dry uniform sand pack impregnated with an aqueous coal tar mixture and 2) packed columns of glass beads of various sizes permeated with distilled water and trichloroethylene. The discernable images of the pore space and the interface of the two liquids in the pore space indicated that magnetic resonance imaging could be a viable tool to determine spatial distribution and mass fraction of hydrocarbon liquids in subsurface contamination.

Detection of Persistent Organic Pollutants in the Mississippi Delta Using Semipermeable Membrane Devices
Zimmerman, L.R.; E.M. Thurman; K.C. Bastian.
The Science of the Total Environment, Vol 248 No 2-3, p 169-179, 2000

Semipermeable membrane devices (SPMDs) passively accumulate hydrophobic organic compounds when placed in water. The devices consist of a low-density polyethylene (LDPE) lay-flat membrane filled with 1 gram of a high molecular weight lipid, triolein, that cannot diffuse through the membrane. The LDPE membrane mimics a biological membrane in its ability to allow selective diffusion of organic compounds. After the deployment period, SPMDs are retrieved from the water (in the tests described here, surface water streams), dialyzed, cleaned up with gel permeation chromatography and silica gel, and analyzed using gas chromatography/ mass spectrometry (GC/MS) or gas chromatography/electron capture (GC/ECD) techniques. From SPMDs placed in five Mississippi Delta streams in 1996 and 1997, the persistent organic pollutants aldrin, chlordane, DCPA, DDT, dieldrin, endrin, heptachlor, hexachlorobenzenes, mirex, nonachlor, and toxaphene were detected, in addition to two insecticides still in use, the organophosphate chlorpyriphos and the organochlorine endosulfan. Two low-solubility herbicides not seen commonly in surface water, pendimethalin and trifluralin, also were detected.

Chlorinated Ethenes from Ground Water in Tree Trunks
Vroblesky, Don A.; Christopher T. Nietch; James T. Morris.
Proceedings of the U.S. Geological Survey Toxic Substances Hydrology Program Technical Meeting, 8-12 March 1999, Charleston, South Carolina. Volume 3 of 3: Subsurface Contamination from Point Sources.
U.S. Geological Survey Water-Resources Investigations Report 99-4018C, p 607-614, 1999

The purpose of this investigation was to determine whether tree-core analysis could be used to delineate shallow ground-water contamination by chlorinated ethenes. Analysis of tree cores from baldcypress, tupelo, sweetgum, oak, sycamore, and loblolly pine growing over shallow ground water contaminated with cis-1,2-dichloroethene (cDCE) and trichloroethene (TCE) showed that those compounds also were present in the trees. The cores were collected and analyzed by headspace gas chromatography. Baldcypress, tupelo, and loblolly pine contained the highest concentrations of TCE, with lesser amounts in nearby oak and sweetgum. The concentrations of cDCE and TCE in various trees appear to reflect the configuration of the chlorinated-solvent ground-water contamination plume. Baldcypress cores collected along 18.6-meter vertical transects of the same trunks showed that TCE concentrations decline by 30 to 70% with trunk height. The ability of the tested trees to take up cDCE and TCE make tree coring a potentially cost effective and simple approach to optimizing well placement at this site

Bethlehem Landfill Groundwater Containment Monitoring
Hasemeier, R.F.; M.A. Knight.
In Situ Remediation of the Geoenvironment: Proceedings of the Conference held in Minneapolis, Minnesota, 5-8 October 1997.
American Society of Civil Engineers, Reston, VA. ISBN: 0-7844-0278-7. Geotechnical Special Publication No 71, p 473-488, 1997

No abstract available.

Identification of Contaminated Soils by Dielectric Constant and Electrical Conductivity
Kaya, Abidin (Ctr. for Envir. Engrg. and Sci. Technologies (CEEST), Dept. of Civ. and Envir. Engrg., Univ. of Massachusetts, Lowell, MA); Hsai-Yang Fang (Dept. of Civ. and Envir. Engrg., Lehigh Univ., Bethlehem, PA).
Journal of Environmental Engineering, Vol 123 No 2, p 169-177, Feb 1997

The use of dielectric constant and electrical conductivity of the soil-fluid system has been suggested to overcome deficiencies of current identification and characterization methods. However, little is known about the dielectric behavior of a contaminated soil-fluid system. The authors describe a study undertaken to investigate the possibility of using dielectric constant and electrical conductivity to characterize and identify contaminated fine-grained soils. The dielectric constant and electrical conductivity of kaolinite, bentonite, and local soil were determined at various ion concentrations, organic liquids, and moisture content. Results showed both dielectric constant and electrical conductivity of the soil-fluid system to be mainly controlled by pore fluid.

Multicomponent Geophysical Surveys over Completed Landfill Sites
Fennings, P.J.; B.S. Williams.
Modern Geophysics in Engineering Geology.
Geological Society, London. ISBN: 1897799926. Geological Society Engineering Geology special publication, 0267-9914; no 12, p 125-139, 1997

No abstract available.

The Use of Rayleigh Waves to Detect the Depth of Shallow Landfill
Butcher, A.P.; W.S.A. Tam.
Modern Geophysics in Engineering Geology.
Geological Society, London. ISBN: 1897799926. Geological Society Engineering Geology special publication, 0267-9914; no 12, p 97-101, 1997

No abstract available.

Resistivity (-Method) Method for Environmental Monitoring: a New Approach
Narayan, S.; M.B. Dusseault.
Modern Geophysics in Engineering Geology.
Geological Society, London. ISBN: 1897799926. Geological Society Engineering Geology special publication, 0267-9914; no 12, p 89-95, 1997

No abstract available.

Practical Bedrock Aquifer Characterization Using Borehole Geophysics and Multi-Level Wells
Gernand, Jeff (Gannett Fleming, Inc., Baltimore, MD); Bruce Rundell (U.S. EPA, Philadelphia, PA); Chen-yu Yen (Gannett Fleming, Inc., Baltimore, MD).
Practice Periodical of Hazardous, Toxic, and Radioactive Waste Management, Vol 5 No 2, p 111-118, Apr 2001

This paper describes a strategy for characterizing contaminated bedrock aquifers using borehole geophysics and multilevel wells that greatly increases the chances of success. Although these methods can be expensive, proper application may reduce long-term monitoring costs. The case study site is a hilltop landfill overlying a heterogeneous bedrock aquifer and surrounded by homes using domestic wells. Borehole geophysical and heatpulse-flowmeter data identified the number of water-bearing zones (WBZs) per 30 meters drilled. Multilevel wells focused sampling on WBZs and provided detailed plume characterization and monitoring to help protect local domestic wells. A review of logs from one monitoring well shows how borehole geophysics identified seven individual WBZs, and sampling of the multilevel well revealed important variations in chemical and potentiometric signatures between the WBZs. This detailed characterization supported the site conceptual model and demonstrated that domestic wells were not threatened. The increasing use of low-flow sampling techniques and the rising popularity of monitored natural attenuation remedies should lead to increased application of this strategy.

Laboratory and Field Tests for Studying Gas Flow Through Municipal Solid Waste Landfill Cover
Maciel, Felipe Jucá; José Fernando Thomé Jucá.
Advances in Unsaturated Geotechnics (Proceedings of sessions of Geo-Denver 2000 held in Denver, Colorado, 5-8 August 2000).
American Society of Civil Engineers, Reston, VA. ISBN: 0-7844-0510-7. Geotechnical Special
Publication No. 99, p 569-585, 2000

Abstract not available.

Three-Dimensional Site Characterization Technologies for DNAPL Contaminated Sites
Naval Facilities Engineering Command, Washington, DC.
NFESC TDS-2072-ENV. 8 pp, Nov 1999

This technical data sheet briefly describes the results of several demonstrations of high-resolution seismic reflection imaging surveys and electromagnetic resistivity surveys to characterize DNAPL in the subsurface and also addresses benefits/advantages, limitations, demonstration planning and implementation, and cost effectiveness of the technologies. More information: http://erb.nfesc.navy.mil/erb_a/restoration/technologies/invest/geo_phys/tds-2072.pdf

Rapid Characterization of Metals in Sediments Using X-Ray Fluorescence (XRF) Technology
Naval Facilities Engineering Command, Washington, DC.
NFESC TDS-2076-ENV. 2 pp, Feb 2000

XRF is not intended to replace the more rigorous laboratory-based analysis for regulatory purposes.

Rather, XRF provides near real-time data to produce a contaminant distribution map while the crew is in the field, without relying on time consuming and costly laboratory analysis to complete the distribution picture. XRF analysis allows better delineation of contaminant distribution by providing higher data density in a time- and cost-effective manner. More information: http://erb.nfesc.navy.mil/erb_a/restoration/technologies/invest/fld_chem/tds-2076-xray.pdf

QwikSed: A Bioluminescent Sediment Toxicity Test
Naval Facilities Engineering Command, Washington, DC.
NFESC TDS-2077-ENV. 2 pp, Feb 2000

The Navy has developed a rapid bioassay system (QwikSed) that is proving to be a valuable asset for conducting bioassays on marine sediments. The basis of detection is to measure a reduction in light from a bioluminescent dinoflagellate such as Gonyaulux polyedra or Ceratocorys horrida following exposure to a toxicant. The toxic response is usually measured within 24 hours from the start of the test and can be conducted for a 4-day acute test or a 7- to 11-day chronic test. A measurable reduction or inhibition in bioluminescence is an adverse effect. The endpoint used to measure this light reduction is the IC50 (a 50% reduction in light output when compared to control cells). The QwikSed unit has been licensed to Sealite Instruments, Inc., of Ft. Lauderdale, Florida. The cost of the QwikSed analyzer and supporting software is approximately $15,000. The instrument includes built-in software that automatically prints the raw data and calculates the mean, standard deviation, coefficient of variation, percent of control, and the estimated IC50. The QwikSed unit can be connected to either a printer via a serial port on the back of the unit for direct printouts, or it can be connected to a computer for further manipulation or graphing of data using a software program such as Excel. More information: http://erb.nfesc.navy.mil/erb_a/restoration/technologies/invest/fld_chem/tds-2077-qwiksed.pdf

Rapid Sediment Characterization of PCBs with ELISA, an Immunoassay Technique
Naval Facilities Engineering Service Center, Port Hueneme, CA.
NFESC TSD-2086-ENV. 3 pp, Jun 2001

The enzyme-linked immunosorbent assay (ELISA) is used for environmental field analysis because it can be optimized for speed, sensitivity, and selectivity, has a long shelf life, and is relatively simple to use. Immunoassay tests use antibodies to bind with a target compound or class of compounds, in this case PCBs. Concentrations of the PCB and the target analyte are identified through a colorimetric reaction. The determination of PCBs presence is made by comparing the color developed by a sample of unknown concentration with the color formed by the standard containing the analyte at a known concentration. The concentration of the PCB is determined by the intensity of color in the sample and is measured with a spectrophotometer. Immunoassay kits are relatively quick and simple to use with a short training session. Detection limits can vary depending on the dilution series used. The detection limit for PCBs test kits in soil ranges from 50 to 500 ppb. http://erb.nfesc.navy.mil/erb_a/restoration/technologies/invest/fld_chem/tds-2086-rsc.pdf

Innovative Field Technique Used at NSCS Athens, Georgia
Robinson, John (SOUTHNAVFACENGCOM); Scott Flickinger; Keith Henn; Steve Ruffing (TetraTech NUS, Inc.).
RPM News, p 1-2, Spring 2001

An innovative field-screening method is available to profile soil conductivity and volatile organic compounds (VOCs) in soil and ground water. The Membrane Interface Probe/Soil Conductivity (MIP/SC) system developed by Geoprobe assisted in the characterization of a low-level dissolved-phase gasoline plume adjacent to the Naval Supply Corps School (NSCS) in Athens, Georgia. The technique provided real-time results, which assisted in the selection of optimal soil and ground-water sampling locations, thereby reducing the overall number of samples required. Soil and ground-water contamination originated from previously leaking pipes associated with underground storage tanks (USTs) located at the Navy Exchange Gas Station. Ground-water contamination migrated downgradient, and despite a remedial action to treat both soil and ground water, legacy contamination remains in relatively low-permeability soil approximately 200 to 300 feet from the source area. The MIP/SC system was used to collect continuous vertical profiles of VOC data and soil conductivity at the site. Using direct push technology (DPT), the 1.5-inch-diameter probe is driven into the ground at a rate of one foot per minute. The MIP portion of the probe measures VOCs by heating the soil and/or water to temperatures between 80 and 250 degrees Celsius. The VOCs diffuse across a membrane and into a carrier gas. The gas is then analyzed, using a combination of a flame ionization detector (FID), a photo ionization detector (PID), and an electrical conductivity detector (ECD) (for chlorinated VOCs only) in a laboratory-grade gas chromatograph at the surface. The SC portion of the system uses a dipole measurement arrangement in which an alternating current is passed from the center of the probe to the probe body. The voltage response of the soil to the current is measured across these same two points. Lower conductivities indicate sands (high-permeability material), while higher conductivities indicate silts and clays (low-permeability material). The continuously measured results are captured by data-logging software and displayed in real time as the probe is advanced. At the Athens site, the soil conductivity results with the MIP results indicate that the plume is being contained in place by low-permeability soil. The data generated from the MIP/SC system and media sampling enabled TetraTech NUS, Inc., to strategically locate three additional monitoring wells at the point of highest subsurface contamination. However, there are a few drawbacks to the MIP/SC system that require additional evaluation: 1) the MIP/SC system is more costly to operate than hand-held instruments, suggesting that a cost analysis should be done for each project; 2) the results are qualitative for contaminants and will require confirmation sampling to obtain quantitative results; 3) a separate DPT hole is required for sample collection, meaning additional sample collection time; and 4) the system is only in the early stages of gaining regulatory approval as a media delineation technique for UST programs.

Innovative Technology Applied at El Toro MCAS
Long, Alexandria (NFESC); Lynn Hornecker (SWDIV); Crispin Wanyoike (Earth Tech).
RPM News, p 10, Spring 2001

A recently implemented innovative technology is capable of continuously measuring air permeability as well as contaminant concentration along a well screen during soil vapor extraction (SVE). The technology was applied at El Toro Marine Corps Air Station (MCAS) by Earth Tech, Inc., using PRAXIS Environmental Technologies patented PneuLog™ system. The technology can be used to assess remediation progress and provide data to help optimize the efficiency of the existing system. The primary contaminant at the cleanup site on El Toro MCAS is trichloroethylene (TCE). An SVE system had been installed late in 1999 and had worked effectively for more than six months. As TCE vapor concentration levels leveled off below the closure thresholds, PneuLog™ was implemented to evaluate the vertical distribution of residual TCE vapors and vapor flow profiles. PneuLog™ was applied to ten representative wells around the site. In general, the PneuLog™ technology combines an airflow probe with a volatile organic compound (VOC) detector to make in situ, real time measurements as a function of depth. The PneuLog™ instrument, which consists of a probe attached to a cable, was lowered into each SVE well. The probe continuously measures contaminant concentration and airflow along the entire well screen length. Soil vapor flow measurements are performed using a downhole flowmeter. VOC measurements are made using a photoionizing detector. The contaminant concentration profiles are calibrated with off-site analyses of vapor samples collected from the well head. The PneuLog™ results produced useful information. The airflow data showed no areas of restricted airflow, proving that the existing system was operating effectively. The contaminant concentration profiles confirmed that there were no individual pockets of high concentrations of TCE along the well screen. Additionally, the concentration data demonstrated that the highest concentrations were measured close to ground water and were a result of offgassing from the contaminated ground water. PneuLog™ has been successfully implemented on a variety of DoD and commercial sites across the United States. The data it produces are not only useful for SVE optimization, but can also be used for soil venting design, risk assessments, and accelerated site characterization. Traditional alternatives are available; however, they do not offer the simultaneous measurement of flow rates and vapor concentrations while they are typically more time consuming and costly than PneuLog™. At El Toro MCAS, it is estimated that utilizing PneuLog™ cost approximately 50% of the amount needed to collect similar data using traditional methods. Contact: Lynn Hornecker, RPM Naval Facilities Engineering Command, Southwest Division, (619) 532-0783, horneckerlm@efdsw.navfac.navy.mil.

Potential Contaminant Migration at a Contaminated Soils Landfill Site in Quebec
Cabral, A.; L. Demers; R. Ciubotariu.
Advances in Transportation and Geoenvironmental Systems Using Geosynthetics (Proceedings of sessions of Geo-Denver 2000 held in Denver, Colorado, 5-8 August 2000).
American Society of Civil Engineers, Reston, VA. ISBN: 0-7844-0515-8. Geotechnical Special Publication No 103, p 68-80, 2000

Abstract not available.

Artificial Neural Networks in Remote Sensing of Hydrologic Processes
Islam, Shafiqul; Ravi Kothari, Dept. of Electrical and Computer Engrg. and Computer Sci., Univ. of Cincinnati, Cincinnati, OH.
Journal of Hydrologic Engineering, Vol 5 No 2, p 138-144, Apr 2000

Remote sensing technologies coupled with ongoing and planned remote sensing can be used to generate hydrologic data at spatial, temporal, and spectral resolutions never previously available. Artificial neural networks (ANNs) are being developed to characterize, model, and predict complex multisource remotely sensed hydrologic data. The authors review and examine the utility of ANNs for hydrologic applications, with particular emphasis on remote sensing of precipitation, soil moisture, and multisource land surface data. Recurrent neural networks are reviewed in addition to more popularly used multilayer feedforward networks for prediction and self-organization neural networks in spatial characterization of heterogeneous land surface processes.

Assessment of the Potential Risks of Landfills by Determination of Trace Metals in Groundwater by ICP-MS
Ulrich, A.; H.-R. Zweifel; A.C. Johnson.
Plasma Source Mass Spectrometry: Developments and Applications.
Royal Society of Chemistry, Cambridge, UK. ISBN: 0854047271. p 263-270, 1997

Abstract not available.

Coupling of GC with ICP-MS for Trace Metal Speciation
De Smaele, T.; L. Moens; R. Dams.
Plasma Source Mass Spectrometry: Developments and Applications.
Royal Society of Chemistry, Cambridge, UK. ISBN: 0854047271. p 109-123, 1997

Abstract not available.

Rapid On-Line Separation and Determination of Arsenic (III) and (V) in Waters by Inductively Coupled Plasma Mass Spectrometry
Cox, A.G.; C.W. McLeod; M. Nishikawa [et al.].
Plasma Source Mass Spectrometry: Developments and Applications.
Royal Society of Chemistry, Cambridge, UK. ISBN: 0854047271. p 145-151, 1997

Abstract not available.

Role of Geophysics in Expedited Site Characterization: Case History
Kjartanson, B.H. (Civ. Engrg., Iowa State Univ., Ames, IA); J.D. Wonder ( U.S. DOE Ames Lab., Spedding Hall, Iowa State Univ., Ames, IA); R.C. Benson (Technos Inc., Miami, FL); L. Yuhr (Technos Inc., Miami, FL); A.J. Bevolo (U.S. DOE Ames Lab., Spedding Hall, Iowa State Univ., Ames, IA).
Practice Periodical of Hazardous, Toxic, and Radioactive Waste Management, Vol 2 No 1, p 33-47, Jan 1998

Geophysical techniques were successfully incorporated into an ESC project at an oil seepage basin site on DOE's Savannah River site to define the limits of buried wastes, detect and map an inorganic plume emanating from the waste trenches, and define the approximate depth and lateral continuity of major stratigraphic units across the site. When integrated with minimally intrusive direct push technologies, the geophysical techniques provided the framework for the development of the conceptual site model.

The refined model was then used to guide ground-water contaminant sampling to define the spatial extent of the inorganic and organic plume emanating from the waste trenches.

Inverse Modeling of Field Tracer Data to Characterize DNAPL Contamination
Nicot, Jean-Philippe; Daene C. McKinney; Gary A. Pope.
Aesthetics in the Constructed Environment: Proceedings of the 24th Annual Water Resources Planning and Management Conference, 6-9 April 1997, Houston, Texas.
American Society of Civil Engineers, Reston, VA. ISBN: 0-7844-0228-0, p 420-425, 1997

Abstract not available.

Establishing Landfill Gas as a Cause of Groundwater Contamination
Kraemer, T.A.; M. Carpenter; J. Hartley.
Water Resources and the Urban Environment '98: Proceedings of the 1998 National Conference on Environmental Engineering, 7-10 June 1998, Chicago, Illinois.
American Society of Civil Engineers, Reston, VA. ISBN: 0-7844-0349-X. p 20-25, 1998

Abstract not available.

Leak Detection in Pipes by Frequency Response Method
Mpesha, Witness; Sarah L. Gassman; M. Hanif Chaudhry, Dept. of Civ. and Envir. Engrg., Univ. of South Carolina, Columbia.
Journal of Hydraulic Engineering, Vol 127 No 2, p 134-147, Feb 2001

The authors describe the use of the frequency response method to determine the location and rate of leakage in open loop piping systems. A steady-oscillatory flow, produced by the periodic opening and closing of a valve, was analyzed in the frequency domain by using the transfer matrix method, and a frequency response diagram at the valve developed. In a leaking system, this diagram has additional resonant pressure amplitude peaks that are lower than the resonant pressure amplitude peaks for the system with no leaks. Several piping systems have been successfully analyzed for all practical values of the friction factor to detect and locate individual leaks of up to 0.5% of the mean discharge. The method requires the measurement of pressure and discharge fluctuations at only one location and has the potential to detect leaks in real-life pipe systems conveying different types of fluids, such as water and petroleum.

Underground Storage Tank Detects Leaks
Civil Engineering ASCE, Vol 69 No 8, p 30, Aug 1999

Abstract not available.

Monitoring Subsurface Barrier Integrity Using Perfluorocarbon Tracers
Sullivan, T.M.; J. Heiser; A. Gard; G. Senum, Brookhaven National Lab., Upton, NY.
Journal of Environmental Engineering, Vol. 124, No. 6, June 1998, pp. 490-497

Perfluorocarbon tracers (PFTs) have been tested as a means of barrier verification at the Hanford geotechnical test facility, where a soil/cement barrier was emplaced around a buried drum. PFTs were injected beneath the drum for three days in the center of the barrier 3 meters below grade. The concentration of PFTs in seven external and two internal monitoring wells was measured as a function of time over a 17-day period. The data have been analyzed to determine barrier integrity and PFT diffusion rates through the barrier. This paper discusses the experimental design, test results, data analysis, and modeling of PFT transport in the subsurface system.

Validation of Petroleum Hydrocarbon Extraction Methodologies
Guerin, T.F., Rio Tinto's Research and Technology Group, Hamersley Iron Technical Services, Rio
Tinto's Bioremediation Group, and ICF Kaiser Engineers.
Remediation, Vol 10 No 2, p 85-94, 2000

The solvents, the extraction time, and the extraction method influence the quantification of polycyclic aromatic hydrocarbons (PAHs) in soil. This paper discusses the importance of establishing and being consistent in the application of a vigorous extraction, particularly for commercial laboratories that handle samples of soil in batches, at different times, from a single site investigation or remediation process. It is important that analytical laboratories communicate to the user of the data what variables there are in soil contaminant extractions and how these can affect the final data quality.

Biological Treatment of Oil-Contaminated Sand: Comparison of Oil Degradation Based on Thin-Layer Chromatography/ Flame Ionization Detector and Respirometric Analysis
Oh, Y.-S.; W.-Y. Choi; Y.-H. Lee; S.-C. Choi; S.-J. Kim, Microbiology Lab., Marine Biology Div., Korea Ocean Research & Development Inst., Ansan, Korea.
Biotechnology Letters, Vol 22 No 7, p 595-598, 2000

Oil biodegradation in oil-contaminated sand was measured by both respirometric and thin-layer chromatography/flame ionization detector (TLC/FID) methods. Amendments of inorganic nutrients and an oil-degrading yeast increased the initial CO2 production rate by 5-15 fold, which was not detected by the TLC/FID analysis. However, it was possible to monitor the accumulation of resin/asphaltene fraction up to 130% by the TLC/FID analysis during the biodegradation process.

Five More Canadian Airports Purchase New Fuel Leak Detection System As a Result of Successful Installation in Montreal
Business Wire, 15 Mar 2001

After the success of its innovative new underground pipeline leak detection systems at two major Montreal airports, Vista Research, Inc. (Sunnyvale, California), has installed the equipment at airports in five additional Canadian cities: Calgary, Edmonton, Halifax, Toronto and Vancouver. The leak detection system, which is being used in airports throughout North America, was first installed at Montreal's Dorval and Mirabel International Airports, locations chosen by Air Canada as test sites in 1998. Air Canada investigated leak detection technologies that would perform tightness or pressure testing of underground high-pressure airport hydrant systems. Among those examined was the Vista HT-100 leak detection system. Several other pressure testing methods were tried, but it was determined that the Vista leak detection technology, with its testing methodology, leak threshold criteria, ability to improve accuracy through repetitive testing, and competitive price, was the most compatible with the requirements of Air Canada, the Canadian Fuel Consortia and the operation of the Montreal fuel systems. The two units at Montreal have exceeded the vendor's performance claims and fully comply with the testing requirement for hydrant systems. The advantage of Vista's fuel-line pressure tests is that they can, in a few hours, accurately account for changes in fuel volume caused by temperature variations. Alternative pressure-test methods require that fuel systems be shut down for long periods, which is impractical at major airports. The only other systems on the market require airports to include fuel additives that can be detected by sensors in the ground, or to install tracer wires in trenches along pipelines. The Vista system can detect leaks as small as 0.00214 percent of the pipeline volume within a three-hour test, typically conducted late at night. It works by calculating the expected change in volume as the outside ground and air conditions cause temperature changes in the fuel in the pipeline. If the fuel volume does not change in accordance with the expectations, it is an indication that there is a leak in the system. Vista's equipment can be permanently installed and designed to test pipeline systems as often as daily, or a mobile version can be trucked in for periodic tests. There are two versions of the Vista equipment: the HT-100 is designed for underground pipelines containing more than 3,000 gallons, and the LT-100 is designed for truck loading racks and medium-length lines containing up to 10,000 gallons. Both systems feature automatic compensation for thermal expansion and contraction of liquid in the line, thus eliminating the major source of error in leak detection tests based on fuel

Application of Borehole-Radar Methods to Image Two Permeable Reactive-iron Walls at the Massachusetts Military Reservation, Cape Cod, Massachusetts
Joesten, P.K. (U.S. Geological Survey); J.W. Lane Jr.; J.G. Savoie; R.J. Versteeg.
SAGEEP 2001: Symposium on the Application of Geophysics to Engineering and Environmental Problems, 4-7 March 2001, Denver, Colorado.
Environmental and Engineering Geophysical Society (EEGS), Wheat Ridge, CO. CD-ROM, 2001.

A pilot-scale study was conducted at the Massachusetts Military Reservation on Cape Cod to assess the use of a hydraulic-fracturing method to create vertical permeable reactive barriers (PRBs) of zero-valent iron to remediate ground water contaminated with chlorinated solvents at depths exceeding the range of conventional iron-wall installation methods. At the test site, ground-water contamination extends from 24 to 37 meters (m) below land surface. A treatment zone consisting of two parallel reactive-iron walls 12 m long, 13 m high, and 0.15 m thick, separated by about 6 m, was designed to intersect and remediate a portion of the CS-10 plume. The U.S. Geological Survey used a cross-hole, common-depth radar scanning method to test the continuity and estimate the lateral and vertical extent of the two walls. The cross-hole radar surveys were conducted in boreholes on opposite sides of the iron injection zones. Significant decreases in the amplitude of the radar pulse observed in scans traversing the injection zones were interpreted by comparing radar field data to results of two-dimensional, finite-difference, time-domain models and laboratory-scale physical models developed to predict the effects of wall edges and discontinuities on common-depth cross-hole radar measurements. As part of a feasibility study, single-hole radar reflection data was used successfully to image the walls. More information: http://water.usgs.gov/ogw/bgas/publications/SAGEEP01_131/

Accuracy of Cyanide Analyses: Lessons from On-Site Analyses in the USGS Mobile Geochemical Laboratory, and Implications for Heap Leach Regulatory and Closure Issues
Grimes, D.J.; C.A. Johnson; R.O. Rye.
Closure, Remediation and Management of Precious Metal Heap Leach Facilities, Proceedings, 14-15 January 1999.
University of Nevada Reno Center for Environmental Sciences and Engineering/Division of Continuing Education and North American Mining, Reno, NV. p 63-70, 1999

Using a USGS mobile geochemical laboratory outfitted with an ion chromatograph system, the researchers sampled both effluent and solids from the Pinson mine in Nevada and the Standard Hill mine in California and analyzed the important Fe- and Co-cyanocomplexes directly onsite using methods developed in FY00.

Automatic Monitoring of Heavy Metals in Waters
Beinrohr, Ernest, Dept. of Analytical Chemistry, Slovak Technical Univ., Bratislava, Slovakia.
11th Annual International Conference on Heavy Metals in the Environment, 6-10 August 2000, Ann Arbor, Michigan.
University of Michigan, School of Public Health, Ann Arbor, MI (CD-ROM). Contribution #1371.

This paper describes an automatic system for continuous monitoring of trace concentrations of heavy metals in water. The computer-controlled analyzer consists of a simple flow system with a robust coulometric cell enabling the measurement of various trace elements such as Ag, As, Bi, Cd, Cr, Cu, Fe, Hg, Mn, Pb, Sb, Se, Zn, as well as chlorides, bromides, iodides, phosphates, acids, bases, and ammonia. The device was tested with the monitoring of Hg in industrial waste waters and Fe and Mn in mineral water. Metal concentrations down to the µg/L (ppb) level were measured at measurement frequencies up to 10-40 in an hour. More information: http://www.sph.umich.edu/ehs/heavymetals/TechnicalProgram.html

Determination and Speciation of Copper in Natural Waters by Square Wave Anodic Stripping Voltammetry
Bazzi, Ali (Univ. of Michigan at Dearborn); Donna Hollandsworth; Nicholas Irish, Jerome Nriagu (Univ. of Michigan at Ann Arbor).
11th Annual International Conference on Heavy Metals in the Environment, 6-10 August 2000, Ann Arbor, Michigan.
University of Michigan, School of Public Health, Ann Arbor, MI (CD-ROM). Contribution #1372.

Although square wave voltammetry (SWV) has been reported to be more sensitive than differential pulse techniques by a factor of 2 to 4, most of the speciation and analysis studies of natural waters for heavy metals by electrochemical methods have been done using differential pulse anodic stripping voltammetry (DPASV). The authors report on the determination of total dissolved copper in samples taken from Saginaw Bay, Michigan, by square wave anodic stripping voltammetry (SWASV) using a hanging mercury drop electrode (HMDE). Samples were analyzed for total dissolved copper after filtration and proper digestion with ultra pure nitric acid using standard addition technique. Analyses were carried out with a deposition time of 15 minutes at a deposition potential of -0.75 V vs. Ag/AgC1. Values ranging from 5.11 to 19.73 nM of copper were obtained from different stations and at various depths.

In Situ Measurement of Trace Metals in an Oligotrophic Lake: Comparison of Results Obtained by Peepers and DGT
Alfaro-De la Torre, Ma. Catalina; André Tessier, INRS-Eau, Univ. du Québec, Sainte-Foy, Québec, Canada.
11th Annual International Conference on Heavy Metals in the Environment, 6-10 August 2000, Ann Arbor, Michigan.
University of Michigan, School of Public Health, Ann Arbor, MI (CD-ROM). Contribution #1376, 2000

The technique of Diffusion Gradients in Thin (DGT) films is a potentially powerful means of obtaining information on the in situ speciation of trace metals. This study moves beyond the simple synthetic solutions used so far in the laboratory to test DGT samplers, and compares the concentrations of Cd and Ni measured by DGT and dialysis samplers (peepers) that were deployed in the water column of an oligotrophic acidic lake. Cadmium and Ni concentrations measured by DGT films in the lake were higher than those measured by in situ dialysis. Co-diffusion of major cations, which was not taken into account in the original DGT film theory, could explain the field results. More information: http://www.sph.umich.edu/ehs/heavymetals/TechnicalProgram.html

Earthworms as Bioindicators of Mercury Pollution
Hinton, Jennifer; Marcello M. Veiga, Dept. of Mining and Mineral Process Engineering, Univ. of British Columbia.
11th Annual International Conference on Heavy Metals in the Environment, 6-10 August 2000, Ann
Arbor, MI.
University of Michigan, School of Public Health, Ann Arbor, MI (CD-ROM). Contribution #1018.

A simple, cost-effective indicator that might be used to identify Hg toxicity and bioavailability in soil would be particularly beneficial in regions of the world such as developing countries, where mercury pollution can be extensive, yet resources limited. Earthworms are simple, well-studied creatures that can quickly provide indications of bioavailability at relatively low costs. A methodology using the earthworm Eisenia foetida has been developed to evaluate the bioavailability of Hg in mining tailings and aqueous solutions. Results indicate that E. foetida do accumulate Hg, and a positive correlation exists between Hg concentrations in worm tissues, the substrate they consume, and the length of exposure. The effect of natural organic acids as mediators of Hg bioavailability was investigated. Metallic Hg was dissolved in tannic acid and made available to the worms in a substrate of paper and silica sand. Total Hg and MeHg were analyzed to determine whether methylation of Hg was occurring in the substrate, directly within the worms (e.g. in the intestines), or in the tannic acid-Hg solution. The MeHg:Total Hg ratio was up to 160 times higher in worm tissues than both the tannic acid-Hg solution and the substrate. This result is particularly significant in darkwater systems, where naturally occurring organic acids may be facilitating methylation internally within organisms. More information: http://www.sph.umich.edu/ehs/heavymetals/TechnicalProgram.html

Determination of Mercury Species Using ICP/MS Techniques
Hintelmann, Holger, Trent Univ., Dept. of Chemistry, Peterborough, Ontario, Canada.
11th Annual International Conference on Heavy Metals in the Environment, 6-10 August 2000, Ann Arbor, MI.
University of Michigan, School of Public Health, Ann Arbor, MI (CD-ROM). Contribution #1104.

This paper presents an overview of different analytical methods using ICP/MS as a detector to determine mercury species in environmental samples. Total mercury is measured using either cold vapor flow injection analysis or cold vapor gold amalgamation preconcentration. Both techniques have absolute detection limits of approximately 1 pg of Mercury per isotope. Methylmercury is determined after GC separation on-line by ICP/MS. These techniques are used to carry out isotope dilution analyses and stable isotope tracing experiments. The RSD for isotope ratio measurements was in the range of 0.5- 2%, depending on the individual method used. More information: http://www.sph.umich.edu/ehs/heavymetals/TechnicalProgram.html

Environmental Mercury Speciation Analysis by Flow-Hyphenation Techniques
Tseng C.M. (Dept. of Marine Sciences, Univ. of Connecticut, Avery Point, Groton); D. Amouroux (Laboratoire de Chimie Bio-Inorganique et Environnement, CNRS, Univ. de Pau et de l'Adour, Pau, France); O.F.X. Donard; W.F. Fitzgerald.
11th Annual International Conference on Heavy Metals in the Environment, 6-10 August 2000, Ann Arbor, MI.
University of Michigan, School of Public Health, Ann Arbor, MI (CD-ROM). Contribution #1105.

To follow the pathways of mercury speciation in the environment, several analytical approaches were developed to determine mercury species in different ecosystem compartments. For gas-phase samples, mercury species were concentrated on chromatographic phases and desorbed in a cryotrapping/separating (CT-GC) unit coupled to a detector. For water samples, the mercury species were determined with a field cryofocusing device using flow injection and hydride generation. For environmental solid samples, mercury species were detected by an online D-CT-GC-QFAAS system after sample preparation by a microwave-assisted technique. The proposed approaches were successfully applied to estuarine environmental matrices for investigating the occurrences and fates of Hg. More information: http://www.sph.umich.edu/ehs/heavymetals/TechnicalProgram.html

Aqueous Speciation of Copper, Manganese, Cadmium and Zinc in the Elizabeth River Estuary (Norfolk, VA) Measured Using the Diffusion Gradient in Thin-Film Technique
Twiss, Michael R. (Ryerson Polytechnic Univ., Toronto, Ontario, Canada); James W. Moffett (Woods Hole Oceanographic Inst., Woods Hole, MA).
11th Annual International Conference on Heavy Metals in the Environment, 6-10 August 2000, Ann
Arbor, MI.
University of Michigan, School of Public Health, Ann Arbor, MI (CD-ROM). Contribution #1134.

The Diffusion Gradient in Thin-film (DGT) analytical technique was applied to samples from the metal-contaminated Elizabeth River estuary in Virginia. DGT probes were deployed in the estuary over a 6-day period, in addition to deployment in discrete water samples collected from the same sites. The authors found the use of DGT suitable for assessing water quality, provided that the flux of organic metal into the DGT probes can be controlled. More information: http://www.sph.umich.edu/ehs/heavymetals/TechnicalProgram.html

Analytical Application of Supported Liquid Membranes in Trace Metal Extraction And Speciation
Ndungu, Kuria (Environmental Toxicology Dept./WIGS, Univ. of California at Santa Cruz); Nii-Kotey Djane (Dept. of Analytical Chemistry, Lund Univ., Lund, Sweden); Lennart Mathiasson; Jan Åke Jönsson.
|11th Annual International Conference on Heavy Metals in the Environment, 6-10 August 2000, Ann Arbor, MI.
University of Michigan, School of Public Health, Ann Arbor, MI (CD-ROM). Contribution #1133.

The supported liquid membrane (SLM) procedure is an emerging trace metal preconcentration

technique that lacks many of the problems (e.g., labor intensity, time, and use of large amounts of reagents) attendant on liquid-liquid extraction (LLE), which has been a standard extraction and preconcentration method for trace metal analysis for several decades. SLM takes advantage of LLE's ability to tune the extraction selectivity by chemical means, but unlike LLE, it is easily automated and can be readily coupled to sensitive detectors such as electrochemical or spectroscopic. Since SLM is selective to the free and/or lipophilic species of the analyte, it often provides a more accurate measure on bioavailability and toxicity of metals in solution than the total dissolved (e.g., < 0.45 mm) metal concentration measurements. Additionally, more rigorous speciation measurements can also be performed by combining different SLM units in series; for example, cationic trivalent chromium and anionic hexavalent chromium can be selectively enriched without an independent chromatographic procedure. These advantages are illustrated in preliminary applications of SLM to measure trace metal concentrations and speciation in natural waters. More information: http://www.sph.umich.edu/ehs/heavymetals/TechnicalProgram.html

Sonic CPT Probing in Support of DNAPL Characterization
Gildea, Martin L.; J.W. Haas; S.P. Farrington; D.E. Chitty; W.L. Bratton, Applied Research Associates, Inc., South Royalton, VT. New England Div.
Report Number: ARA-4717. NTIS: ADA384783. 104 pp, Nov 2000

Cone Penetrometer Technology (CPT) offers advantages over other site characterization technologies in that it is generally faster, less expensive, safer, and generates far less secondary waste than conventional drilling methods. As a result, DoD and DOE are supporting the development of advanced sensors for delivery by the cone penetrometer. To accommodate these new sensors, probe sizes have increased from 1.44-in OD to 1.75-in OD, and currently to 2.25-in OD, and the ability of CPT to reach desired depths has been increased. To enhance the penetration capability of the CPT, a sonic vibratory system was integrated with conventional CPT to advance cone penetrometer sensor packages to even greater depths. This CPT enhancement provides an efficient tool for hazardous waste site characterization, remediation, and monitoring. The report is available full text in a PDF file through the DTIC search engine at http://stinet.dtic.mil/str/tr_fields.html

Ceramic Dosimeters for Time-Integrated Contaminant Monitoring
Martin, H.; M. Piepenbrink; P. Grathwohl, Univ. of Tuebingen, Geological Inst., Applied Geology Group, Tuebingen, Germany.
Proceedings of the 2000 Contaminated Site Remediation Conference: From Source Zones to Ecosystems, 4-8 December 2000, Melbourne, Victoria.
Centre for Groundwater Studies, CSIRO, Wembly, W.A., Australia. Vol 1, p 231-238, 2000

Sampling with ceramic dosimeters (passive samplers, patent pending) is a new method for long-term, time-integrated monitoring of organic pollutants in ground water and surface water. Problems with sample integrity common to other water sampling methods due to transport or storage are avoided with this new sampling method, and the number of necessary analyses is reduced to only a few while monitoring the contaminant concentrations (representative mean values) over the whole sampling period. This concept of time-integrated concentration measurements can be used equally for contaminant monitoring in ground water, rivers, lakes, and wastewater. So far, the method has been developed and tested for polycyclic aromatic hydrocarbons (PAHs), volatile chlorinated hydrocarbons, and volatile aromatic compounds (BTEX), but it can also be used for other organic and inorganic aqueous contaminants.

Probe to Make Mine Waste Safer
Commonwealth Scientific & Industrial Research Organisation (CSIRO-Australia) Media Release No 2001/37, 8 Feb 2001

A probe developed by CSIRO is poised to revolutionize the way mining companies monitor the rehabilitation of Australia's mine sites, especially where acidic mine wastes are present. The presence of oxygen in sulphidic mine wastes results in oxidation of the sulphide minerals, and with water forms sulphuric acid. The resultant acid mine drainage causes contamination of surface and ground water. To reduce or eliminate this contamination, the mineral wastes are commonly covered with earth or synthetic covers. The CSIRO probe provides a detailed and accurate assessment of the long-term stability and effectiveness of these covers to prevent oxygen reaching the mineral wastes by accurately, cheaply, and continually monitoring oxygen levels in mine waste sealed under the covers. Placed at various depths in the earth cover and buried waste, the oxygen probes monitor the effectiveness of the cover by detecting the amount of oxygen present. No oxygen means the covers are doing their job. The oxygen probes eliminate sampling error, reduce processing time and give a clearer indication of trends in the oxygen concentration. The probes can also be used at remote sites and data retrieved using mobile phones and modems (telemetry). Contact: Dr. Brad Patterson, CSIRO Land and Water, 08 9333 6276; Dr. Graham Taylor, CSIRO Land and Water, 08 8303 8437; Ms. Margaret Bryant, CSIRO Land and Water, 08 9333 6215.

Pipeline Leak Detector
Montgomery, Joe M., 700 N. Interchange, Strafford, MO 65757.
U.S. Patent 5,821,403, 13 Oct 1998

A pipeline leak detection apparatus is provided for a fluid dispensing system having a dispenser, a storage tank, and a pump and an electric cut-off valve arranged in hydraulic series with the outlet of the storage tank. The pipeline to be monitored extends between the cut-off valve and the dispenser. A control circuit that operates the cut-off valve such that the valve opens with use of the dispenser and closes with non-use in order to hydraulically isolate the storage tank and pump from the pipeline and dispenser during periods of non-use. The leak detection apparatus is connected in a by-pass loop around the pump. It includes a small pot or plenum, a float switch, and a return line for fuel to spill back into the storage tank. The plenum inlet is connected to a branch in the pipeline near the cut-off valve, and its outlet is connected to the return line to the storage tank. The float switch is mounted to the plenum so that its float extends into the plenum chamber. The electrical side of the float switch is connected in the control circuit so that for as long as the float is floated the switch is maintained in one state and produces no effect on the control circuit, but when the float falls the switch changes state and disables the operability of the electric cut-off valve. That way, during use of the dispenser, a fractional amount of the outflow of the pump is diverted through the plenum to keep the float floated; however, during non-use of the dispenser, the falling of the float corresponds to fluid draining out of the plenum chamber as caused by a leak in the pipeline, the result being the disablement of the electric cut-off valve.

Pipeline Leak Detector
Fiechtner, Bradley T. (San Diego, CA). Owned by Dover Corporation, New York, NY.
U.S. Patent 5,557,965, 24 Sep 1996

This patent describes an apparatus for detecting leaks in a pipeline in a liquid dispensing system. The apparatus generally includes a tank containing a liquid, a dispenser valve disposed remote from the tank, a pipeline connected between the storage tank and the dispenser valve, a pump at the tank for supplying liquid under pressure to the pipeline and an isolation valve between the pump and the dispenser valve to isolate the pump pressure from the pressure in the pipeline between the isolation valve and the dispenser valve. The apparatus further has a pressure sensor between the isolation valve and the dispenser valve for measuring any pressure change in the pipeline between the isolation valve and the dispenser value. A leak simulation valve alternatively may be provided for draining the pipeline to simulate a leak.

High-Precision Leak Detector and Locator
Baumoel, Joseph (c/o Controlotron Corporation, 155 Plant Ave., Hauppauge, NY 11788).
U.S. Patent 5,548,530, 20 Aug 1996

This patent describes a method for detecting the presence of a leak in a segment of a pipeline. The method includes providing a site station having an ultra-sonic transducer assembly at the beginning and end of the pipeline segment, each assembly having two pairs of ultrasonic transducers for determining the sonic propagation velocity V_s of ultrasonic energy emitted by the transducers through fluid in the pipeline. Each pair of ultrasonic transducers is displaced along the pipeline by a preset distance and each defines an ultrasonic energy flow path. The value of V_s for each ultrasonic energy flow path through the fluid in the pipeline is determined at each site station at predetermined time intervals. Values .DELTA.V_s defined as the difference between sequential values of V_s at the predetermined time intervals for each flow path at each site station are formed. The .DELTA.V_s values for each flow path are stored in a memory having a predetermined number of memory cells, where a value of .DELTA.V_s is stored in each cell. A determination is made if there is a correlation in the stored values of .DELTA.V_s for each flow path. If there is a correlation between the .DELTA.V_s values for each path, a discrimination is performed between a correlation caused by zero values of .DELTA.V_s stored in the memory for each path and a correlation of .DELTA.V_s values reflecting that a transient in the fluid in the pipeline has arrived at each site station. Then a determination is made whether the correlation corresponds to a leak.

Method for Characterization of Fuels
Alexander; William R. (Huntington, WV), Assignee: Marathon Ashland Petroleum LLC.
U.S. Patent 6,035,705, 14 Mar 2000

In a principal embodiment, the invention relates to a method in which a water sample containing dissolved hydrocarbon fuel to be identified is contacted with a fiber optic element adapted to adsorb a hydrocarbon fuel on at least a portion of the element, for a time sufficient to adsorb a characterizing amount of the fuel from the water sample. The fiber optic element containing adsorbed hydrocarbon fuel is then removed from the water sample, and then at least the portion of the fiber optic element containing adsorbed fuel is immersed in or surrounded with water. The adsorbed hydrocarbon fuel is allowed to desorb from the fiber optic element while the rate of desorption of the fuel from the fiber optic element is measured by a fiber optic chemical sensor system of which the fiber optic element is a part. The set of values derived from the concentration measurements together identify or characterize the hydrocarbon fuel, and may further be represented mathematically by a desorption ratio value which is characteristic of the fuel.

Selective Multi-Chemical Fiber Optic Sensor
Sanghera; Jasbinder S. (Greenbelt, MD); Pureza; Pablo C. (Burke, VA); Aggarwal; Ishwar D. (Fairfax Station, VA); Nau; Gregory (Alexandria, VA), Assignee: The United States of America as represented by the Secretary of the Navy (Washington, DC).
U.S. Patent 5,525,800, 11 Jun 1996

A fiber optic sensor for detecting at least one chemical by evanescent wave spectroscopy comprises a generator of a light signal, a mirror for introducing the light signal into a fiber, a clad optical chalcogenide glass fiber, a mirror for directing the light signal from the fiber into a detector, and a detector for detecting chemicals by the fiber. The fiber comprises a core and a clad having lower refractive index than the core enveloping and being in continuous contact with the core, at least one region on the fiber completely or partially devoid of the clad, and a polymer disposed in the region having affinity for the chemical(s). There being a different polymer in each region if there is more than one region.

Method and Apparatus for Calibrating a Leak Detector
Filippi, Ernest A.; Kenneth L. Miller, Campo/Miller, Porterville, CA.
U.S. Patent 5,883,301. 28 pp, 16 Mar 1999

An automated calibration apparatus and method for calibrating an electronic leak detection system for a fluid piping system uses a calibrated leak device with an orifice that releases fluid at a constant calibrated leak rate. The calibrated leak device is connected to the fluid piping system and a pump is activated to pressurize the fluid piping system. The pump is deactivated, and pressure decay in the fluid piping system resulting from fluid release from the calibrated leak device is measured. The leak sensitivity of the leak detector is then adjusted based on the measured pressure decay versus time with the calibrated leak. More information: http://www.uspto.gov/patft/index.html

Automatically Calibrated Pressurized Piping Leak Detector
Inventors: Filippi, Ernest A.; Kenneth L. Miller. Patent Assignee: Campo/Miller, Porterville, CA.
U.S. Patent 5,526,679, 18 Jun 1996

A pressure decay leak detection system is calibrated for a particular piping system using a leak mechanism with a known leak rate attached to the piping system. Pressure decay in the piping system is monitored while the system is leaking, pressure versus time data defining an acceptable pressure decay profile is stored. In one embodiment, this data is scaled to obtain a profile applicable to different leak rates. The detection system performs a test by sensing decaying pressure in the piping system, determining a slope of measured pressure decay versus time for an increment of pressure decay, comparing a slope of the observed pressure decay with a slope of the acceptable pressure decay profile, and providing a failure indication if the slope of the observed pressure decay exceeds the slope of the acceptable pressure decay profile.

Hazardous Fluid Leak Detector
Inventors: Gray, Harold E.; Felder M. McLaurin; Monico Ortiz; William A. Huth. Patent Assignee: The United States of America as represented by the United States Government, Washington, DC.
U.S. Patent 5,517,181, 14 May 1996

A device or system for monitoring for the presence of leaks from a hazardous fluid is disclosed that uses two electrodes immersed in deionized water. A gas is passed through an enclosed space in which a hazardous fluid is contained. Any fumes, vapors, etc. escaping from the containment of the hazardous fluid in the enclosed space are entrained in the gas passing through the enclosed space and transported to a closed vessel containing deionized water and two electrodes partially immersed in the deionized water. The electrodes are connected in series with a power source and a signal, whereby when a sufficient number of ions enter the water from the gas being bubbled through it (indicative of a leak), the water will begin to conduct, thereby allowing current to flow through the water from one electrode to the other electrode to complete the circuit and activate the signal. The invention described here was developed under Contract No. DE-AC08-88NV10617 between the United States Department of Energy and EG&G Energy Measurements, Inc.

Airborne Geophysical Surveying for Hazardous Waste Site Characterization on the Oak Ridge Reservation, Tennessee
Doll, W.E. (Oak Ridge National Lab., Oak Ridge, TN); J.E. Nyquist (Temple Univ., Philadelphia, PA); L.P. Beard (Geological Survey of Norway, Trondheim, Norway); T.J. Gamey (Oak Ridge National Lab., Oak Ridge, TN).
Geophysics, Vol 65 No 5, p 1372-1387, Sep-Oct 2000

Airborne geophysical methods that were developed for mineral and petroleum exploration can, with some modification, be applied to environmental problems where large areas must be characterized. A helicopter survey that deployed magnetic, electromagnetic, and radiometric sensors carried out one of the first large-scale airborne environmental surveys at a U.S. government facility at Oak Ridge, Tennessee in 1993 1994. The survey included testing of a new airborne electromagnetic system designed specifically for environmental applications and for controlled field tests of magnetic systems. Helicopter-borne magnetic measurements were capable of discriminating groups of as few as ten metallic 208-liter (55-gallon) storage drums under representative field conditions. Magnetic and electromagnetic sensors were able to distinguish groups of metal-filled waste disposal trenches within disposal sites, but were unable to resolve individual trenches. Electromagnetic data proved to be the most effective airborne technique for geological mapping in this portion of the Appalachian fold-and-thrust belt and for locating karst features. Radiometric measurements were useful both in geological mapping and in detecting zones of high radiation related to hazardous waste. The Oak Ridge survey proved valuable for quickly screening large areas and for locating anomalies for subsequent ground follow-up. On-board video was used to reduce the number of instances of ground follow-up by allowing the visual screening of anomalous areas.

DC Resistivity and IP Methods in Acid Mine Drainage Problems: Results from the Copper Cliff Mine
Tailings Impoundments
Yuval; Douglas W. Oldenburg, U.B.C.-Geophysical Inversion Facility, Dept. of Geophysics and Astronomy, Univ. of British Columbia, Vancouver, BC, Canada.
Journal of Applied Geophysics, Vol 34 No 3, p 187-198, 1996

Oxidation of sulfide minerals in the mine tailings impoundments at Copper Cliff, Ontario generates acidic conditions and elevated concentrations of dissolved metals and sulfates in the pore water. The pore water migrates away from the tailings to pose a potential environmental hazard if it should reach nearby water systems. There is a need to characterize this potential environmental problem and to assess the future hazards. A combined DC resistivity and Induced Polarization (IP) survey was carried out along one of the major flowpaths in the tailings and the data were inverted to produce detailed electrical conductivity and chargeability structures of the cross section below the survey line. The conductivity distributions are directly translated, through theoretical and empirical relations, to a map of the concentration of the total dissolved solids (TDS) along the cross section and thereby provide insight about the current pore water quality. The sulfide minerals are the source of the IP response and thus, when combined with borehole data, the chargeability model can be used to estimate the amount and distribution of the sulfides.

3D Resistivity Imaging of Buried Oil- and Tar-Contaminated Waste Deposits
Chambers, Jonathan (Fluid Processes and Waste Management Group, British Geological Survey, Keyworth, Nottingham, UK); Richard Ogilvy; Philip Meldrum; Johan Nissen (ABEM Instrument AB, Sundbyberg, Sweden).
European Journal of Environmental and Engineering Geophysics, Vol 4, p 3-15, 1999/2000

This case study illustrates the advantages of 3D resistivity surveys for mapping concealed, highly irregular tarpits containing industrial waste, mainly from oil reprocessing and coal mining. The survey was carried out using a network of individual lines within a grid measuring 95 m x 95 m. The data were modelled using a 3D inversion program (RES3DINV) and the resulting resistivity distributions were then displayed as volumetric 3D tomograms. Three zones of low resistivity were identified as pits 4N, 4S, and 1A, respectively. The model provided valuable diagnostic information on the geometry of the pits, the distribution and nature of in-filling waste materials, and zones where leachate had infiltrated the bedrock. The results were confirmed by trial pits, cone penetration tests, historic photographs, and boreholes.

Chemical Soil Physics Phenomena for Chemical Sensing of Buried UXO
Phelan, James M.; Stephen W. Webb, Sandia National Lab., Albuquerque, NM.
UXO Forum 1999, 25-27 May 1999, Atlanta, GA

Technology development efforts are under way to apply chemical sensors to discriminate inert ordnance and clutter from live munitions that remain a threat to reutilization of military ranges. The chemical signature is affected by multiple environmental phenomena that can enhance or reduce its presence and transport behavior and affect the distribution of the chemical signature in the environment. For example, the chemical can be present in the vapor, aqueous, and solid phases. The distribution of the chemical among these phases, including the spatial distribution, is a factor in designing appropriate detectors, e.g., gas, aqueous or solid phase sampling instruments. To minimize the consequences of a false negative, a fundamental understanding of the environmental conditions that affect the chemical signature is needed to describe the favorable and unfavorable conditions of a chemical detector-based survey. UXO source emission measurements are being made to estimate the chemical flux from a limited set of ordnance items. Phase partitioning analysis has been completed to show what the expected concentrations of chemical analytes would be from total concentrations measured in the soil. The soil moisture content in the dry region has been shown to be critical in the attenuation of soil gas concentrations by increased sorption to soil particles. Numerical simulation tools have been adapted to include surface boundary conditions such as solar radiation, surface boundary layer (which is a function of wind speed), precipitation and evaporation, and plant cover/root density to allow transport modeling and evaluate long term processes. Results of this work will provide performance targets for sensor developers and support operational decisions regarding field deployments. More information: http://www.uxocoe.brtrc.com/UXOForumDocs/Forum99/UT_Phelan.pdf

DC Resistivity and Induced Polarisation Investigations at a Waste Disposal Site and Its Environments
Aristodemou, E.; A. Thomas-Betts, T.H. Huxley School of Envt., Earth Science and Eng., Royal School of Mines, Imperial College of Science, Technology and Medicine, London, UK.
Journal of Applied Geophysics, Vol 44 No 2-3, p 275-302, 2000

The authors relied on the results of geoelectrical surveys carried out to monitor the spread of contamination in underlying aquifers from a landfill site to estimate the hydraulic conductivities in a contaminant transport model. The type of waste deposited and the influence of the geological environment were the crucial factors investigated via DC resistivity and time domain induced polarisation (IP) methods. The landfill was mainly a liquid disposal site with existing borehole information showing that the waste contained high concentrations of both inorganic (chlorides, sulphates) and organic matter (indicated by high values of chemical oxygen demand and total organic carbon). The aquifer system consists of three sand aquifers with intervening semi-pervious clay aquitards. The presence of organic waste was a factor in suggesting that the IP method could be employed as a diagnostic tool. The IP measurements showed high apparent chargeability values (80-120 ms) on top of the landfill, possibly due to the presence of disseminated solid metallic waste or the high organic load of the liquid waste present. The IP line parallel to the ground-water flow direction and close to the landfill produced chargeability anomalies that may be associated with a plume of organic waste. No chargeability anomalies were observed on the second IP line. The bulk resistivities _o obtained from the resistivity inversions and the fluid resistivities _w from adjacent boreholes allowed hydraulic conductivities to be estimated.

First LC/MS Determination of Cyanazine Amide, Cyanazine Acid, and Cyanazine in Groundwater Samples
Ferrer, I.; D. Barcelo; E.M. Thurman.
Environmental Science & Technology, Vol 34 No 4, p 714-718, 2000

Cyanazine and two of its major metabolites--cyanazine amide and cyanazine acid--were measured at trace levels in ground water using liquid chromatography/atmospheric pressure chemical ionization/mass spectrometry (LC/APCI/MS). Solid-phase extraction was carried out by passing a 20 mL ground-water sample through a cartridge containing a polymeric phase (PLRP-s), with recoveries ranging from 99 to 108% (n) 5. Using LC/MS detection in positive ion mode, useful structural information was obtained by increasing the fragmentor voltage, which permitted the unequivocal identification of the compounds in ground-water samples with low sample volumes. The newly developed method was evaluated for the analysis of ground-water samples from a New York site affected by the compounds under study. The results suggest that the metabolites cyanazine acid and cyanazine amide may leach to ground water and serve as sources for deisopropylatrazine.

OINT 3D Interpretation of Radio-Magnetotelluric (RMT) and Transient Electromagnetic (TEM) Data from an Industrial Waste Deposit in Mellendorf, Germany
Hordt, A. (Inst. für Geophysik und Meteorologie der Univ. zu Köln, Köln, Germany); S. Greinwald
(Bundesanstalt für Geowissenschaften und Rohstoffe, Hannover, Germany); A. Hoheisel; F.M. Neubauer; G. Schaumann; B. Tezkan.
European Journal of Environmental and Engineering Geophysics, Vol 4, p 151-170, 1999/2000

A radiomagnetotelluric (RMT) and central loop transient electromagnetic (TEM) survey was carried out over an industrial waste disposal site in Germany. The combined application was intended to obtain a good resolution over the entire depth of the range of interest. The RMT data provide information on the shallower structures, while the TEM data are sensitive to the deeper section, with an overlapping range in between. First, the data are interpreted separately, using 1D inversion for the TEM data, and 2D inversion for the RMT data. The results are combined into a 3D starting model for the TEM data, which is modified using a trial-and-error forward modeling strategy. In the joint interpretation step, the model is further modified until a satisfactory fit to both data sets is obtained. The waste disposal site was not sealed at the bottom; hence, the focus of the interpretation is on whether chemical compounds of the wastes (mainly magnesium drosses) might have penetrated into the deeper environment. A modeling study based on the final 3D model shows clear evidence for a significant amount of conductive material below the assumed bottom of the disposal. The migration was confirmed by drilling tests. The joint interpretation reduced ambiguity and provided greater confidence in the result when it was compared to a separate interpretation.

Secondary Ion Mass Spectrometry Investigation of Interfacial Chemistry of Intact Microorganisms
Ingram, J.C. (Idaho National Engineering and Environmental Lab., Idaho Falls, ID); F.S. Colwell; R.M. Lehman; W.F. Bauer; A.D. Shaw (Westminster Christian Academy, St. Louis, MO).
Eos: Transactions of the AGU, Vol 81 No 48, Fall Meeting Supplement, 2000

Rapid detection of intact microorganisms remains a difficult problem, despite its importance in environmental remediation and subsurface science. The authors are evaluating static secondary ion mass spectrometry (SIMS) methods as a means for rapidly detecting and identifying intact microorganisms. The basis for the approach is to use SIMS to probe the top layers of the surface to collect unique mass spectral signatures of the cell membrane chemistry of a microorganism by analyzing intact cells with no sample preparation. In a previous study, a method for identifying the mineral phases of basalt surfaces utilizing imaging SIMS was developed to provide a tool for investigating the interfacial chemistry of contaminants present in subsurface basalt and sediments. SIMS provides an advantage over other techniques as it probes only the top few layers of the sample surface, and it is highly sensitive for both elemental and molecular species. An extension of this work is to apply SIMS to the detection of microorganisms with the end goal of utilizing SIMS to investigate microbial communities directly on the rock surface. Initial work involved collecting SIMS spectra of 38 microorganisms to be were compared to fatty acid profiles determined by the Microbial Identification System, which is based on gas chromatographic data. The results indicate that surface bombardment using a molecular primary beam cleaves the ether linkage characteristic of Archea at the glycerophosphate backbone of the phospholipid components of the cell membrane. Similar cleavage at the ester linkage in Eubacteria is also observed. This cleavage enables direct detection of the fatty acid conjugate base by static SIMS. In addition to the fatty acid detection, partial least squares analyses of the SIMS data were performed to determine if SIMS was capable of differentiating Gram positive and Gram negative bacteria. These results show a clear grouping of the Gram-positive species and Gram-negative species We have observed evidence that suggests SIMS has the capability of probing other chemistries present in the cell membrane. An example of this is the comparison of SIMS spectra of two strains of Shewanella alga (BrY and adhesion deficient RAD20), which differ mainly in their ability to bind to ferric oxides. Biochemical evidence showed that the BrY strain contained proteins on the cell surface which enabled adhesion to occur whereas those proteins were absent in the adhesion-deficient RAD20 strain. The SIMS cation spectra of these strains shows marked differences in the even mass ions which suggests that the differences in protein composition of these two strains is reflected in the SIMS data.

VLPI Develops Test for Major Contaminant: PurTest® MTBE Leads Water Industry
Vital Living Products, Inc., News Release, 17 Jul 2001

Vital Living Products, Inc., of Matthews, North Carolina, announces that it has developed PurTest® MTBE, part of a comprehensive line of do-it-yourself home water testing kits. This is the first consumer test for widespread water contamination caused by MTBE (methyl tertiary-butyl ether), a potential carcinogen. MTBE is a gasoline additive used over the past 20 years to enhance gasoline combustion and reduce tailpipe emissions, especially carbon monoxide. MTBE readily dissolves in water and moves rapidly through soils and aquifers, thus contaminating water supplies in both private and public wells. PurTest® MTBE will give a positive test result when 15 parts per billion are detected with the at-home test. The MTBE test kit will be available at retail locations nationwide for under $20.00.

Gas Chromatographic Techniques and Applications
Handley, Alan J.; Edward R. Adlard.
Sheffield Academic Press, Sheffield, UK. ISBN: 0849305217. 320 pp, 2001

This volume provides an overview of the state of the art in gas chromatography with an emphasis on new technologies. The authors--all drawn from respected industrial and academic laboratories --consider developments in gas chromatographic techniques over the last decade. Application areas are addressed within individual chapters.

VLF-R and EM-31 Measurements at Three Closed Landfills in Western Finland (DeP1)
Rajala, P.
Proceedings of the Fifth International Meeting of the Environmental and Engineering Geophysical Society, September 1999, Budapest, Hungary

Abstract DeP1 is not available.

Detection of Subsurface Hydrocarbon Contamination Using Various Geophysical Methods (DeP2)
Holczinger, I.
Fifth Meeting of Environmental & Engineering Geophysical Society European Section, 6-9 September 1999, Budapest, Hungary

Anstract DeP2 not available.

DC Resistivity Monitoring of the Unsaturated Zone Beneath a Lined Landfill Site in the UK (DeP3)
Taylor, S.B.; R.D. Barker.
Fifth Meeting of Environmental & Engineering Geophysical Society European Section, 6-9 September 1999, Budapest, Hungary

Abstract DeP3 not available.

Resistivity and Inductive Electromagnetics for Delineation Studies of Leakage from a Waste Deposit in Southern Sweden (DeP4)
Wisén, R.; T. Dahlin; C. Bernstone.
Fifth Meeting of Environmental & Engineering Geophysical Society European Section, 6-9 September 1999, Budapest, Hungary

Abstract DeP4 not available.

Landfill Monitoring by Airborne EM and Ground Resistivity Measurements (DeP6)
Lohva, J.; T. Jokinen; H. Vanhala; M. Lahti.
Fifth Meeting of Environmental & Engineering Geophysical Society European Section, 6-9 September 1999, Budapest, Hungary

Abstract DeP6 not available.

Application of Geoelectrical Methods to the Detection of Polluted Soils at Shallow Depth (DeP7)
Zuberek, W.M.; B. Zogala; J. Pierwola.
Fifth Meeting of Environmental & Engineering Geophysical Society European Section, 6-9 September 1999, Budapest, Hungary

Abstract DeP7 not available.

Detection of Hydrocarbon Contaminated Soils by Electromagnetic Techniques (INCO-Copernicus IC-15-CT96-0801) (DeP8)
Derobert, X.; Ph. Cote; M. Piccolo.
Fifth Meeting of Environmental & Engineering Geophysical Society European Section, 6-9 September 1999, Budapest, Hungary

Abstract DeP8 not available.

Remediation of As-Organic CW Contaminated Sites (DeP9)
Spyra, W.P.W.
Fifth Meeting of Environmental & Engineering Geophysical Society European Section, 6-9 September 1999, Budapest, Hungary

Abstract DeP9 not available.

Difference Inversion of ERT Data: a Fast Inversion Method for 3-D In Situ Monitoring
LaBrecque, Douglas J. (Multi-Phase Technologies LLC, Sparks, NV); Xianjin Yang (Advanced Geosciences, Inc., Austin, TX).
Journal of Environmental & Engineering Geophysics, Vol 6 No 2, p 83 89, 2001

A 3-D Occam's inversion algorithm for electrical resistivity tomography was modified to allow for inversion on the differences between the background and subsequent data sets. The algorithm has been optimized for in situ monitoring applications. The resistivity obtained by the inversion of background data serves as the a priori model in the difference inversion. There are several advantages to this method: convergence is fast, since the inverse routine needs only to find small perturbations about a good initial guess; and systematic errors such as those due to errors in field configuration and discretization errors in the forward modeling algorithm tend to cancel. The result is that we can fit the difference data far more closely than the individual potentials. Better data fits often equate to better resolution with fewer inversion artifacts. The difference inversion technique was applied to monitoring in situ steam remediation in Portsmouth, Ohio, and monitoring flow in fluid fractures at the Box Canyon site near the Idaho National Engineering Laboratory. Difference inversion produced high-quality images with fewer artifacts, and only took 25 to 50% of the run time of standard Occam's inversion in the Box Canyon case.

The Effects of LNAPL Biodegradation Products on Electrical Conductivity Measurements
Cassidy, Daniel P. (Western Michigan Univ., Kalamazoo, MI); D. Dale Werkema Jr.; William Sauck; Estella Atekwana; Silvia Rossbach (Univ. of Missouri Rolla); Joe Duris.
Journal of Environmental & Engineering Geophysics, Vol 6 No 1, p 47-52, 2001

Laboratory experiments were conducted to test the hypothesis that anomalously high conductivities in and below the free-product zone found at many sites with aged contamination by LNAPLs can result from products of LNAPL biodegradation. Soil from a hydrocarbon-impacted site with anomalously high conductivities was washed repeatedly to remove soluble constituents, re-contaminated with diesel fuel (DF), and the pores filled with water to simulate a saturated smear zone. Nutrients were provided at levels approximating those observed at the site, which resulted in anaerobic conditions due to DF biodegradation. Within 120 days, the increase in specific conductivity from microbial activity was 2,100 S/cm, caused by an increase in total dissolved solids (DS) of over 1,700 mg/L. The results show that products of LNAPL biodegradation can dramatically increase the conductivity at impacted sites.

Geophysical Mapping of a Shallow Contaminant Plume in Thin Glacial Till, Northeast Newfoundland
Guzzwell, G. Keith, Dept. of Environment and Labour, Government of Newfoundland and Labrador,
St. John's, Newfoundland, Canada.
Journal of Environmental & Engineering Geophysics, Vol 4 No 4, p 241-249, 1999

Geophysical techniques have been used to map the lateral extent of a ground-water contaminant plume in a region of thin glacial till overburden at a domestic waste disposal site in Newfoundland. This site is typified by waste cells that have significant quantities of material above the water table. VLF tilt angle, VLF-Resistivity, and terrain conductivity data were collected. The depth to bedrock at each of the ten water monitoring wells located on the site was known from drilling and used to derive the top layer resistivity distribution over the grid. This resistivity was then used in an algorithm to determine the depth to bedrock at each grid point and to produce a bedrock topography map. Two bedrock channels, along which contaminant can flow down slope, have been identified, one on each side of the site. The presence of contaminant in these channels is identified from the terrain conductivity data and the processed VLF tilt angle data. Ground probing radar (GPR) data were collected along the road traversing the site. The GPR data clearly indicate the boundaries of the waste cells, but bedrock cannot be unambiguously discerned. The results from the geophysical surveys are highly correlated with chloride ion concentrations in water samples from the wells in the study area.

Electromagnetic Induction and GPR Measurements for Creosote Contaminant Investigation
Guy, Erich D. (U.S. EPA, Region V, Chicago, IL); Jeffrey J. Daniels; Jennifer Holt; Stanley J. Radzevicius; Mark A. Vendl (Dept. of Geological Sciences, Ohio State Univ., Columbus).
Journal of Environmental & Engineering Geophysics, Vol 5 No 2, p 11-19, 2000

Multifrequency EM induction and GPR parallel dipole (co-pole) and orthogonal dipole (cross-pole) surveys were conducted to assist in the characterization of a former industrial site prior to its cleanup by the Ohio EPA and the U.S. EPA. High concentrations of creosote are present in clay-rich surficial soils as a result of many years of wood treating at the site. The approximate extent of contamination at the site and the locations of several contaminant-filled structures were determined through the use of quadrature-phase EM data and cross-pole GPR data. These data formed basis for the site remediation plan. Geophysical data interpretations were confirmed through exploratory trenching and soil sampling subsequent to the completion of the study, which demonstrates the potential for mapping the extent and variation with depth of resistive compounds under circumstances where high levels of contamination are present with relatively conductive background materials. Cross-pole GPR data were more useful than co-pole data at the site for imaging several structures containing creosote that would have remained undiscovered and acted as future sources of contamination.

A New Method of Subsurface Imaging--the LASI High Frequency Ellipticity System: Part 1. System Design and Development
Sternberg, Ben K., Lab. for Advanced Subsurface Imaging (LASI), Dept. of Mining and Geological Engineering, Univ. of Arizona, Tucson, AZ.
Journal of Environmental & Engineering Geophysics, Vol 4 No 4, p 197-213, 1999

An electromagnetic (EM) imaging system has been developed that allows enhanced identification of buried hazardous waste and contaminated soil or ground water. This system utilizes frequencies in the range of 31 kHz to 32 MHz, a frequency range that lies between conventional low-frequency EM induction surveys and high-frequency ground-penetrating radar (GPR) surveys. This capability permits interpretation of both conductivity and dielectric permittivity in loessy soils. Mapping the dielectric permittivity will allow location of environmental targets that are not detectable with more commonly used conductivity or resistivity tools. This paper details design and development of the system. The design incorporates unique transmitter and receiver coils which combine wide bandwidth and high sensitivity. It also includes a method for eliminating electric-field interference, which is vital for accurate measurements in this frequency range.

A New Method of Subsurface Imaging--the LASI High Frequency Ellipticity System: Part 2. Data Processing and Interpretation
Birken, Ralf A., Lamont-Doherty Earth Observatory of Columbia Univ., Palisades, NY.
Journal of Environmental & Engineering Geophysics, Vol 4 No 4, p 215-226, 1999

This paper is Part 2 of a three-part series. The author describes data processing and interpretation for the subsurface imaging system developed by the Laboratory for Advanced Subsurface Imaging (LASI) at the University of Arizona. A unique, simultaneous-calibration method is used to measure the magnetic-field ellipticity with very high accuracy. Four calibration signals at frequencies f1, f2, f4, and f5) are injected into the receiver coils at the same time that the data signal at frequency f3 is being received. The calibration signals are interpolated in order to derive a calibration response at the data frequency. A three-dimensional ellipticity is calculated from the three components of measured magnetic field data.

A New Method of Subsurface Imaging--the LASI High Frequency Ellipticity System: Part 3. System Tests and Field Surveys
Birken, Ralf A., Lamont-Doherty Earth Observatory of Columbia Univ., Palisades, NY.
Journal of Environmental & Engineering Geophysics, Vol 4 No 4, p 227-240, 1999

This paper is Part 3 of a three-part series. It details five case histories showing the use of the subsurface imaging system developed by the Laboratory for Advanced Subsurface Imaging (LASI) at the University of Arizona. The first case history involved tests over a "perfectly conducting earth," which was used for verification of the system response. The test was made over an 8 m by 15 m aluminum sheet, which provided a good approximation to a perfectly conducting earth. Since the electrical properties of a perfectly conducting earth are precisely known, the researchers were able to accurately calculate the expected electromagnetic response over the subject area. These measurements were used to verify the system response and demonstrate that field data that accurately matches model results can be produced. The second test was over a homogeneous earth. The soil electrical properties at this site had been previously characterized with well logs and with laboratory electrical-property measurements. The third test used large-scale physical modeling. Measured electromagnetic responses over barrels, pipes, and metal sheets closely matched theoretical responses. The next two case histories were demonstration surveys performed at DOE's Idaho National Engineering Laboratory (INEL). The first was at a site known as the acid pit in the Radioactive Waste Management Complex (RWMC) at INEL. This survey successfully mapped the subsurface extent of an acid plume containing various hazardous materials. The second demonstration took place at INEL's Cold Test Pit, which was designed to simulate hazardous waste of the type that is buried at many DOE sites. The survey effectively mapped the distribution of the various waste forms.

DC Resistivity Monitoring of Potassium Permanganate Injected to Oxidize TCE In Situ
Nyquist, Jonathan E. (Temple University, Philadelphia, PA); Bradley J. Carr (Oak Ridge National Lab., Oak Ridge, TN); R. Kim Davis (Geophex, Inc., Raleigh, NC).
Journal of Environmental & Engineering Geophysics, Vol 4 No 3, p 135-147, 1999

DOE's Office of Science and Technology selected the X-701B Site at the Portsmouth Gaseous Diffusion Plant, Piketon, Ohio, for a demonstration of in situ chemical oxidation. The goal was to oxidize trichloroethylene (TCE), present in both the soil and ground water, by circulating a solution of potassium permanganate between two horizontal wells. Potassium permanganate is a salt. Laboratory measurements showed that the addition of 1% potassium permanganate increased the fluid conductivity of a Portsmouth ground-water sample from 339 to 7,250 mS/m, or equivalently, decreased the electrical resistivity from 2.9 ohm-m to 0.14 ohm-m. Although the contaminated aquifer is only about 1.5 meters thick at this site and is overlain by nearly 8 meters of clay, geophysical modeling showed that if the injection flooded a sufficient portion of the aquifer, the change in resistivity would be detectable from the surface using DC resistivity. Field measurements made using a multi-electrode resistivity system along two lines one parallel and one perpendicular to the two horizontal wells showed that the potassium permanganate injection was detectable as a subtle change in the resistivity data. The resistivity data showed that the potassium permanganate did not migrate uniformly between the two horizontal wells. Instead, both the resistivity data and a bromide tracer test conducted in 1992 showed a zone of preferential flow at the southern end of the wells. The agreement of the resistivity data with both the tracer test data and with potassium permanganate levels measured in a network of monitoring wells showed that it is feasible to use resistivity to monitor an electrolyte injected in situ to oxidize contaminants. This study provides an example of how geophysical methods can be used to reduce the number of ground-water wells needed to monitor site remediation.

How Important is the Orientation of a Horizontal Loop EM System? Examples from a Leachate Plume and a Fault Zone
Nobes, David C., Dept. of Geological Sciences, Univ. of Canterbury, Christchurch, New Zealand.
Journal of Environmental & Engineering Geophysics, Vol 4 No 2, p 81-85, 1999

The coupling between a horizontal loop EM (HLEM) system and a buried object, e.g., a buried pipe, is well-established; the response depends on the orientation of the transmitter-receiver loop system relative to the object in question. However, diffuse boundaries between terrain materials, which even when highly contaminated are orders of magnitude less conductive than metallic targets, do not respond like discrete buried objects. Survey results from different sites illustrate that the difference due to system azimuth is generally negligible.

Characterization of Disposal Sites from Surface Wave Measurements
Haegeman, W.; W. F. Van Impe, Laboratory of Soil Mechanics, Ghent University, Belgium.
Journal of Environmental & Engineering Geophysics, Vol 4 No 1, p 27-33, 1999

Nonintrusive Rayleigh wave investigation using the Spectral-Analysis-of-Surface-Waves (SASW) technique is a tool for characterization of waste disposal sites in a broad range of waste materials. Applications of SASW surveys for site characterization at waste fills include determination of stiffness parameter profiles for the waste mass, evaluation of cover thickness, location of native ground interface, and quantitative monitoring of improvement techniques. SASW surveys at five waste fills in Belgium composed of municipal waste, dredging sludge, and cinders or slags demonstrate the potential applications of SASW and provide insight into typical shear wave velocity profiles for treated and untreated waste materials. This paper highlights some important areas in which the SASW technique can be used successfully.

Landfill Delineation and Characterization Using Electrical, Electromagnetic and Magnetic Methods
Lanz, Eva; Alan Green; David E. Boerner; Hansruedi Maurer, Inst. of Geophysics, ETH-Hoenggerberg, Zurich, Switzerland.
Journal of Environmental & Engineering Geophysics, Vol 3 No 4, p 185-196, 1998

Three geophysical techniques have been used to determine the boundaries and contents of a small composite landfill. Initial widely spaced electrical resistivity soundings and profiles provided gross information on the distribution of electrical conductivity with depth and the approximate position of the landfill. Frequency-domain electromagnetic data were then collected on a dense grid that encompassed the landfill and surrounding sediments. Using a simple new technique, these vertical- and horizontal-mode data were inverted jointly to yield shallow electrical conductivities and approximate estimates of magnetic susceptibility. Finally, optically pumped Cesium-vapor sensors were employed in the acquisition of total-field and vertical-gradient magnetic data over the same area as the electromagnetic data. Together, the resultant geophysical data sets revealed two distinct waste pits separated by a zone of undisturbed ground 20-40 meters wide. The irregular boundaries of the two waste pits were determined equally well on the electrical conductivity, magnetic susceptibility, and vertical-gradient magnetic maps. By comparing anomalies on these maps, it was possible to distinguish ferrous and non-ferrous metallic objects outside of the landfill and to identify sand- and gravel-rich units within the dominantly fine-grain sediments of the region.

Hydrogeologic Site Characterization Using Azimuthal Resistivity Surveys
Marin, Luis E. (Univ. Nacional Autonoma de Mexico, Mexico City); Birgit Steinich; D. Jaglowski (Dept. of Civil and Environmental Engineering, Univ. of Michigan, Ann Arbor); M.J. Barcelona.
Journal of Environmental & Engineering Geophysics, Vol 3 No 4, p 179-184, 1998

The purpose of this paper is to evaluate whether azimuthal resistivity surveys (ARS) provide diagnostic information for mapping preferred hydraulic conductivity directions in unconsolidated sediments as they do in fractures/jointed media. Nineteen azimuthal resistivity surveys (ARS) were conducted in three different places within a shallow, unconsolidated, sand and gravel aquifer located at the Michigan Integrated Remediation Technology Laboratory (MIRTL). The observed electrical anisotropy ratios were not significant enough to represent changes in the regional ground-water flow direction. However, the results from this work suggest that ARS may be used as part of an integrated hydrogeological study that may yield semi-quantitative information of the electrical anisotropy with increasing electrode spacing.

Contributions of Surface Geophysics to Environmental Site Investigation of Former Oil Distribution Terminals
Vickery, Anna C.; Bruce A. Hobbs, Dept. of Geology and Geophysics, Univ. of Edinburgh King's Buildings, Edinburgh, UK.
Journal of Environmental & Engineering Geophysics, Vol 3 No 3, p 101-109, 1998

Before the start of invasive investigations at a site formerly used to house oil distribution terminals, a trial geophysical survey was conducted involving magnetics and electromagnetics. The trial demonstrated that the electromagnetic technique, involving a Geonics EM31 soil conductivity meter, was capable of detecting subsurface metal pipes and contaminant concentrations resulting from the oil terminal works. Trial pits and trenches validated the geophysical interpretation, even to the extent of finding tarry contaminants emanating from the ends of broken pipes.

Choice of the Best Model in 2-D Geoelectrical Imaging: Case Study from a Waste Dump Site
Olayinka, Abel I.; Ugur Yaramanci, Dept. of Applied Geophysics, Technical Univ. of Berlin, Berlin, Germany.
European Journal of Environmental and Engineering Geophysics, Vol 3, p 221-244, 1998

A procedure is presented for choosing the best model in 2-D geoelectric imaging in the presence of a high-resistivity contrast. Inversion of synthetic data using an algorithm based on the smoothness-constrained non-linear least squares optimisation technique has shown that for high resistivity contrasts the model misfit between the inverted model and the original model increases with the iteration number. Consequently, the model that best approximates the true model is attained at a relatively low iteration number whereas the data misfit reduces to a minimum at higher iterations. A case history from a waste dump site in Ibadan, south-western Nigeria, is described. The solid geology comprises quartzite and quartz-schist that have been extensively weathered and fractured. Inversion of the Wenner pseudosection data indicates that the model bedrock resistivities at about the second iteration are geologically realistic. The thickness of the waste dump varies between about 2 to 17 m, while its resistivity is low and lies between 4 to 8 W m. The low resistivity is due to the presence of leachate emanating from the site and this has also polluted the surface waters and ground waters in the immediate vicinity. The authors concluded that geoelectric imaging, with appropriate geologic constraints provided a realistic subsurface image for the noisy environment of the waste dump.

Heavy Metal Pollution Monitoring by Magnetic Susceptibility Measurements Applied to Sediments of the River Mur (Styria, Austria)
Scholger, R., Inst. for Geophysics, Univ. of Leoben, Paleomagnetic Lab., Frohnleiten, Austria.
European Journal of Environmental and Engineering Geophysics, p 25-37, Vol 3, 1998-1999

The applicability of environmental magnetic methods to delineate polluted areas and to quantitatively assess the degree of pollution was tested for sediments of the river Mur in Styria (Austria). More than 500 samples from a 190 km river section between Judenburg and Spielfeld were analyzed by means of petrology, chemical and magnetic methods. The magnetic susceptibility of the sediments was dominated by scale, which is a waste material from metal-producing and metal-manufacturing processes. The linear regression of magnetic susceptibility versus scale content was significant, with 2500*10-6 SI = 1 percent scale (mass content). Chemical analyses of the samples established a clear correlation of heavy metal concentration (especially Cr, Pb, and Zn) with the scale content. Magnetic susceptibility thus provided an indicator for the heavy metal contamination of the river sediments.

Investigation of Environmental Pollution Using Magnetic Susceptibility Measurements
Gelioli, K.; A. Aydin, Dept. of Geophysical Engineering, Karadeniz Technical Univ., Trabzon, Turkey.
European Journal of Environmental and Engineering Geophysics, Vol 3, p 53-61, 1998

Magnetic susceptibility measurements were carried out to map heavy metal pollution from an industrial plant and from cars on a major highway. In the first case, magnetic susceptibility measurements were made to determine the distribution of tailings including heavy metals from a flotation plant. Both the magnetic surface susceptibility in the creek where the tailings are discharged and the magnetic susceptibility of samples collected from the creek and sea floor in a narrow area where the creek reaches the sea were measured in the laboratory. In a mix of the clean sediment samples and tailings collected from the outlet of the flotation plant, it was found that the susceptibility decreases with increasing percentage of tailings. Subsequent geochemical analysis confirmed that samples with low magnetic susceptibility values had high heavy metal content. In the second case, surface magnetic susceptibility measurements were made to find out the distribution of Pb deposited from exhaust gases in an area near the highway west of Trabzon where there is little variation in the sediment type. In the laboratory, a decrease was observed in the magnetic susceptibility of a clean sediment sample which was exposed to exhaust gases for some time. Geochemical sampling confirmed that samples near the highway had relatively low magnetic susceptibility values, whereas sediments away from the highway exhibited relatively high magnetic susceptibility levels consistent with normal background geology. The authors concluded that magnetic susceptibility surveys could provide a rapid reconnaissance tool for mapping elevated levels of heavy metals and anthropogenic pollution, by virtue of anomalous low susceptibility values.

Imaging of Industrial Waste Deposits and Buried Quarry Geometry by 3-D Resistivity Tomography
Ogilvy, R. (British Geological Survey, Keyworth, Nottingham, UK); P. Meldrum; J.Chambers (Dept. of Earth Sciences, Univ. of Sheffield, Sheffield, UK).
European Journal of Environmental and Engineering Geophysics, Vol 3, p 103-113, 1998

The authors present a case study to show the advantages of non-invasive 3-D resistivity surveys for mapping spatially complex and hazardous waste landfills, sites where industrial wastes had been deposited over many years in abandoned sandstone quarries. The survey was undertaken to determine the buried quarry geometry, the depth and nature of overlying backfill, and possible fluid infiltration of the bedrock. The study confirmed that where fluid invasion of the quarry walls is negligible, the strong resistivity contrast with the confining sandstone provided a basis for mapping the quarry boundaries and depth to bedrock. Where fluid migration into the surrounding rocks and fill occurs, the geometry and physical limits of the quarry edge are more difficult to establish. The results showed that the fill material and minimally invaded sandstone had similar or overlapping resistivity values; however, these respective units could usually be distinguished on the basis of their differing spatial geometry when viewed in 3-D space. The results demonstrate the importance of full 3-D inversion for accurate target diagnosis. A 3-D visualization software was used to show the volumetric distribution of intrinsic resistivities obtained from the 3-D inversion models for each area. The software was used to interactively slice and view user-defined iso-resistivity volumes. This approach allowed irregular or complex features to be visualized more readily than in the case of 2-D vertical or horizontal sections.

DC Resistivity and Time-Domain Induced Polarization Survey for the Study of Groundwater Contamination in Bahia, Brazil
Ruhlow, A. (Inst. of Geophysics and Meteorology, Univ. of Köln, Albertus-Magnus-Platz, Köln, Germany); B. Tezkan; O.A.L. de Lima (Universidade Federal de Bahia, Campus Univ. da Federaço,
Inst. de Geociências, Salvador, Bahia, Brazil).
European Journal of Environmental and Engineering Geophysics, Vol 3, p 143-160, 1998

DC resistivity and time-domain induced polarization (IP) measurements were performed near an open-air basin which was used for many years by a huge petrochemical complex in Bahia, Brazil, as a site for liquid organic and inorganic waste disposal. 1-D inversion of resistivity measurements delineated the local geological structure, as well as contaminated zones indicated by conductive anomalies. 3-D DC forward modeling was employed to examine lateral effects of a lake as a possible reason for these anomalies. Finally, the interpretation of the chargeability data allowed the distinction between the local occurrence of lenses of shale and contaminated ground regions, which could not be inferred through resistivity measurements alone.

VLF Used for Waste-Site Assessment
Beamish, D.; P. Meldrum; R. Ogilvy.
European Journal of Environmental and Engineering Geophysics, Vol 3, p 161-178, 1998

The authors examine the applicability of the electromagnetic VLF-R (Resistivity) method for waste-site assessment. The frequencies used in conventional VLF (15 to 30 kHz) provide the deepest penetrations of the multi-frequency extended method of RadioMT. Both methods are appraised. VLF data, being effectively single frequency, are insufficient to resolve 1-D (vertical) structure in any detail. However, at the site investigation scale, the departures from the background, vertically uniform structure are of interest. The purpose of this paper is to demonstrate the degree to which quantitative resistivity information can be obtained from VLF-R data in the context of waste-site assessment when highly conductive leachates are encountered. Improved methodologies for the quantitative assessment of VLF data derive from advances in standard inversion techniques. VLF-R survey data at a former industrial waste site, aided by wide-band (VLF/RadioMT) synthetic modeling and inversion studies, are used to illustrate their shallow (0 to 20 m) resolution capabilities in conductive environments. The application of 2-D standard (smooth-model) inversion to single-frequency VLF-R survey data is found to be effective provided the noise (non-2-D) components of profile data are understood.

DC Resistivity Mapping of Old Landfills: Two Case Studies
Bernstone, Christian; Torleif Dahlin, Dept. of Geotechnology, Lund Univ., Lund, Sweden.
European Journal of Environmental and Engineering Geophysics, Vol 2, p 121-136, 1997

Geophysical investigations were carried out on two old waste-disposal sites in the province of Scania in southern Sweden. The objectives of the surveys were to map the internal structure and to delineate the extent of deposited waste, as well as to gain information about the local geology. The methods used were 2-dimensional DC resistivity, frequency-domain electromagnetics (slingram/FDEM), and magnetics. The resistivity data sets were interpreted with 2-D smoothness-constrained inversion, and the FDEM and the magnetic data sets were contoured. The surveys identified the positions of buried metal objects and delineated sludge ponds, a coastal saltwater front, and geological structures. In addition, leakage plumes were identified at Lernacken by the resistivity survey. The slingram EM equipment was rapid, whereas the 2-D DC resistivity surveys provided valuable depth information that allowed the construction of quasi-3-D models of the ground. The in-phase component in slingram measurements was especially good in localizing individual metal objects, but the total field magnetic measurements also worked well.

Theoretical Solutions for Calculating Leakage Through Composite Liner Systems
Rowe, R.K.; J.R. Booker.
Developments in Theoretical Geomechanics, Proceedings. 16-17 November 2000, Sydney, Australia, p 589-602, 2000

No abstract available.

Application of Remote Sensing Data for Monitoring of Gas Pipeline Right-of-Way
Fung, K.B.; D.W. Fraser; R.P. Gauthier.
Proceedings of GIS '98/RT'98, 6-9 April 1998, p 401-404, 1998

Even though most of the Canadian oil and gas pipelines are buried underground, they can still pose a threat to a fragile environment. Over the last 10 years, monitoring of the network has been done mainly through the use of black and white aerial photographs, ground surveys, and airborne inspection to locate disturbances to the network by accidental spills, encroachment from human activities, and land form changes due to fires, floods, and other natural events. Under the Local Environmental Applications Program, NOVA Gas Transmission Ltd. is collaborating with the Canada Centre for Remote Sensing (CCRS) in a demonstration project to use remote sensing techniques for monitoring the pipeline right-of-way. This paper presents some of the GIS concerns in the project.

True Elemental Speciation in Liquid Chromatography Through Particle Beam Glow Discharge Mass and Optical Spectrometries
Marcus, R. Kenneth (Clemson Univ., Clemson, SC); Terri E. Gibeau; Melissa A. Dempster; Brad Knippel.
PITTCON 2000, 12-17 March 2000, New Orleans, Louisiana

The researchers have coupled a particle beam LC-MS interface to a hollow cathode discharge source (PB-HC) to develop a new type of atomic emission and mass spectrometry detector for speciation studies employing HPLC separations. In the case of AES, trace metals can be determined at the ppb level, with C and H (from ligands) being quantified at the single ppm level. Ratios of non-metal responses provide empirical formula data. For example, each of the natural amino acids can be identified by the ratios of the C/H/N components. Mass spectrometric sampling of the HC plasma produces electron impact-type spectra for organic and organometallic compounds, while free metal ions permit the use of isotopic patterns for identification and quantification through isotope dilution. The paper presents the analytical figures of merit for the PB-HC-AES/MS systems described here. The ability of the PB-HC couplings to characterize combined organic/inorganic sample types has been demonstrated through the analyses of dietary supplements and mixtures of organometallic compounds. Much work remains to be done to make this a truly viable approach.

Gas Chromatography Coupled with Plasma Mass Spectrometry for Speciation: Current Status
Evans, E. Hywel (Univ. of Plymouth, Plymouth, UK); Gavin O'Connor; Bernd Rosenkranz.
PITTCON 2000, 12-17 March 2000, New Orleans, Louisiana

In the search for an analytical method that is both universal and selective in nature, and is also highly sensitive, no single instrument has been developed yet that will accomplish this task. No single source exists that is truly capable of producing molecular ions, fragment ions, and atomic ions solely by varying operating conditions. Such a source would facilitate selective quantitative analysis and qualitative characterization of analyte compounds. This paper outlines the different types of sources coupled with mass spectrometry that the authors have been investigating for use in speciation analysis. Examples are given of microwave and inductively coupled plasmas at atmospheric and low pressure used for element selective detection and as tuneable sources. The authors present examples of applications for environmental monitoring of organo-halide and organo-metallic compounds and describe recent progress in coupling liquid chromatography with a low pressure ICP.

Structural Elucidation of Phospholipid Fatty Acids of Sedimentary Marine Bacteria by GC/MS Analysis of N-acylpyrrolidides Derivatives and Dimethyldisulfides Adducts: A Potential Tool to Evaluate Bioremediation of Oil-Contaminated Areas
Aries, Eric (Faculté des Sciences de Saint-Jérôme, Univ. d'Aix-Marseille, Marseille, France); Pierre Doumenq; Monique Acquaviva; Jacques Artaud; Jean-Claude Bertrand; Mille Gilbert.
PITTCON 2000, 12-17 March 2000, New Orleans, Louisiana

Marine sedimentary bacteria involved in degrading crude oil trapped in marine sediments are known to modify their phospholipid fatty acids (PLFA) in response to environmental shills. This study was undertaken to determine effects of petroleum hydrocarbons on PLFA profiles of two consortia of hydrocarbonoclastic bacteria. The goal was to identify possible biomarkers or characteristic PLFA profiles indicative of hydrocarbonoclastic bacterial activity. Bacterial consortia were reconstituted in vitro by assembling pure marine bacterial hydrocarbonoclastic aerobic strains from a highly contaminated sediment collected near the petroleum industry site of Lavera (Golfe de Fos, France). The consortia were grown successively on a soluble ammonium acetate medium, then on an hydrophobic substrate made of blend Arabian light oil (BAL 250). PLFA methyl esters derivatives were analyzed by GC/MS. Double bond and alkyl branches in fatty acids were confirmed by GC/MS analysis of N-acyl pyrrolidides derivatives and dimethyldisulfides adducts. Growth of consortia on BAL 250 resulted in complex phospholipid fatty acids profiles, exhibiting high amounts of odd saturated, odd monounsaturated, and series of branched fatty acids. Based on those data, a petroleum-utilization index was proposed to discriminate bacterial grown on ammonium acetate and on petroleum. This index is of potential interest for monitoring bioremediation in oil-contaminated areas, because it might offer in situ evidence of the development of hydrocarbonoclastic strains actively involved in biodegradation processes.

A Novel, Inert, Low-Bleed Column for GC/MS
Vickers, Allen K. (J&W Scientific, Inc., Folsom, CA); Roy M. Lautamo; Eberhardt R. Kuhn.
PITTCON 2000, 12-17 March 2000, New Orleans, Louisiana

In recent years, attempts to create new low-bleed phases often were based on arylene-type polymer chemistry. However, this approach is not possible for 100% dimethyl silicone phases. Through the development of an innovative manufacturing technique it is now possible to make inert, low-bleed columns that are truly 100% dimethyl siloxane. The new DB-1 ms shows exceptional inertness towards both acids and bases. The creative manufacturing process reduces the bleed, making this new column a true 100% dimethyl phase specifically designed for GC/MS. And, since it is truly 100% dimethyl, its selectivity is virtually identical to regular 100% dimethyl phases. This paper presents examples of this inertness and low bleed, comparisons to other 100% dimethyl columns, and applications where those characteristics are important

Design and Optimization of Capillary Column Stationary Phases for Volatiles by GC/PID-ELCD and GC/MS
English, Chris M. (Restek Corp., Bellefonte, PA); Dinesh Patwardhan; Frank L. Dorman; Mike J. Feeney.
PITTCON 2000, 12-17 March 2000, New Orleans, Louisiana

With recent changes in U.S. EPA methods for the analysis of volatiles by GC/PID-ELCD, many laboratories have been struggling to achieve resolution of a compound list that is continually expanding. All of the current phases available for these types of analysis suffer from lack of resolution between specific compounds, and many also suffer from low thermal stability and long analysis times. The first half of this paper will discuss an alternative GC column that addresses these issues, designed using computer modeling and new stationary phase functionalities. For years laboratories have been using the "624 / 1301" phase for the analysis of volatiles by GC/MS. There are a variety of problems associated with this column such as co-elutions of target compounds, which share the same primary quantitation ions. This paper discusses the limitations of current columns and the thermodynamic modeling that was used in the development of a new stationary phase, taking into account the specific requirements of the MS system. Compound lists and phase requirements were determined using EPA methods in collaboration with environmental laboratories across the country.

The Design of a New Capillary Gas Chromatographic Column for the Analysis of Dioxins and Furans
Dorman, Frank L. (Restek Corp., Bellefonte, PA); Eric J. Reiner; Mike J. Feeney; Chris M. English.
PITTCON 2000, 12-17 March 2000, New Orleans, Louisiana

Laboratories performing dioxin and furan analyses (ca. U.S. EPA 8290) struggle with achieving the desired resolution for the specific congeners in a reasonable amount of time because no commercially available phase was designed with this separation in mind. This has lead to laboratories using 5% phenyl/95% methyl polysiloxane phases for their thermal stability, and high-cyano-propyl phases for their ability to separate a few specific congeners. The 5% phenyl phases do not separate all congeners as well as desired, resulting in laboratories needing to confirm analyses on the high-cyano phases, which have short lifetimes under the conditions that must be used for this method. The authors describe the historical difficulties with this separation, discuss the concern over the coelution of the most important congeners, and assess the need for development of computer models necessary to design new stationary phases. High-resolution GC/MS data are shown confirming the ability to develop a column with a predicted separation, with a discussion of how this new column can yield more accurate automatic integration and an increase in sample throughput.

Applications of Integrated Analyser Systems Incorporating GC and Continuous Monitors for On-Line Analysis of Gases and Gas Mixtures
Smith, Martin J.C. (Unicam Chromatography, Bar Hill, Cambridge, UK); David Burges; Andrew H. Ditchman.
PITTCON 2000, 12-17 March 2000, New Orleans, Louisiana

A variety of on-line analytical applications are presented that involve the use of gas chromatography in combination with other technologies such as electrolytic oxygen analyzers and aluminum oxide moisture sensors. Integrated analyzer systems are described with facilities for automatic stream selection, automatic testing of the analyzer calibration, and the output of integrated results and alarm conditions to the production control system. Application examples include measurement of trace impurities in a food/beverage grade carbon dioxide plant, analysis of the natural gas fuel supply for ceramic firing ovens, and control of emissions from a toxic gas scrubber.

Rapid Analysis of PAHs in Fly Ash Using Thermal Desorption and Fast GC/TOF-MS
Riley, John T. (Western Kentucky Univ., Bowling Green, KY); Daozhong Zou; Wei-Ping Pan.
PITTCON 2000, 12-17 March 2000, New Orleans, Louisiana

Thermal desorption of samples followed by rapid GC/TOF-MS analysis of PAHs can be completed in less than one hour. In the procedure described, the sample is loaded into the pyrocell and heated to 320 degrees C. The compounds that evolve are swept by an inert gas into a cryo-focusing system, where they are trapped, desorbed on to the GC column, and determined by rapid GC/TOF-MS analysis. The results of a comparative study of the Thermal Desorption - Fast GC/TOF-MS and the conventional purge and trap GC/MS analysis of PAHs in a group of fly ashes are presented in this paper. The study focused on the 16 U.S. EPA priority-pollutant PAHs. Thermal desorption followed by GC/TOF-MS is more efficient than purge-and-trap GC/MS (quadrupole) for identification of the PAHs, and can detect lower concentrations of the PAHs. Also, the Thermal Desorption GC/TOF-MS procedure can produce results from a smaller sample.

Detection of Chemical Vapors by Multispectral Infrared Remote Sensing Imaging
Zhang, Lin (Ohio Univ.,Athens); Gary W. Small.
PITTCON 2000, 12-17 March 2000, New Orleans, Louisiana

This paper describes work on the development of automated detection strategies for the detection of chemical species in multispectral IR remote sensing imaging data. The goal of the work is to use the RS-800 multispectral infrared line scanner (Raytheon TI Systems, McKinney, TX) to image and detect chemical vapor species from an airborne platform. The strategies involve the implementation of an automated detection system and signal processing, image processing, and pattern recognition methods. The chemical species to be detected include ethanol, methanol, ammonia, and sulfur dioxide as released from a hot stack. The resulting chemical vapor plume is imaged with the line scanner system. The researchers are pursuing an "automated intelligent detection system" that can yield qualitative identification results for each analyte against a variety of infrared backgrounds and interferences.

New Potentiometric Sensors for Environmental Monitoring
Pretsch, Erno (Swiss Federal Inst. of Technology (ETH), Zurich, Switzerland); Patrick Bodmer; Alan Ceresa; Monia Fibbioli; Urs Mathis; Titus Zwickl; Werner E. Morf.
PITTCON 2000, 12-17 March 2000, New Orleans, Louisiana

The presentation focuses on optimizing the composition of ISE membrane and inner reference system as well as the calibration and measurement procedures to obtain rugged ISEs suitable for trace level measurements in environmental samples. A simplified theoretical model accurately accounts for the influence of all relevant parameters of the measuring system. Based on recent developments of solid-contact ISEs, miniaturized potentiometric sensor arrays consisting of 10-100 sensing membranes/mm² will become feasible. This will allow the simultaneous monitoring of interfering ions and introduce redundancies by using several membranes to measure the activity of the same ion.

Cross-Reactive Optical Sensor Arrays for Multi-Analyte Sensing
Walt, David R. (Tufts Univ., Medford, MA); Shannon Stitzel; Keith J. Albert; Caroline Schauer; Todd Dickinson.
PITTCON 2000, 12-17 March 2000, New Orleans, Louisiana

Cross-reactive optical sensor arrays combine coherent optical fiber bundles with micron-sized bead sensors. The bead sensors have an incorporated solvatochromic dye and fluorescence changes are monitored by employing a custom built imaging system with CCD detection. Each bead sensor has a unique, characteristic and reproducible temporal fluorescence response profile upon pulsatile delivery of analyte vapor. Multiple bead sensor types are combined to create randomized high-density cross-reactive arrays on the distal tip of an optical imaging fiber. The bead sensors are randomly distributed within the array and are positionally registered by the unique sensor-analyte fluorescence response patterns. Employing micron-sized bead sensors is advantageous because they can be mass-produced and have good sensor-to-sensor reproducibility. This reproducibility is a result of the sensor production method in which polymer and silica beads are dyed in large batches with a solvatochromic dye, producing billions of bead sensors at once. Another benefit to using bead sensors is the redundancy of beads in an array. Each bead is an individual sensor, and every array has hundreds to thousands of each bead type dispersed within the array. By summing the responses of like beads, there is a significant signal-to-noise enhancement in the overall response.

Characterization and Application of a Novel Electro-Chemiluminescent Reaction Involving Cadmium
Whitchurch, Christian (Ohio Univ., Athens); Anthony Andrews.
PITTCON 2000, 12-17 March 2000, New Orleans, Louisiana

Electrochemiluminescence (ECL) is the generation of light during a chemical reaction with at least one of the reagents being generated in situ at the electrode. Electrochemiluminescent reactions involving aqueous metal ions can offer an alternative method for quantitation of dissolved metals. In this case a flow injection system using 1,10-phenanthroline as an ECL reagent in conjunction with Cd2 ions provides sufficient emission for reliable cadmium quantitation. The high throughput of flow injection analysis combined with the relatively simple ECL instrumentation grants a potentially fast and inexpensive method for routine aqueous cadmium determinations. A survey of possible interferent ions has proven the reaction to be quite selective for Cd2, the ion.

Application of a New Anion Exchange Column for the Determination of Inorganic Anions in Environmental Waters by Ion Chromatography
Jackson, Peter E. (Dionex Corp., Sunnyvale, CA); M.J. Coffey; Christopher A. Pohl; Charanjit Saini.
PITTCON 2000, 12-17 March 2000, New Orleans, Louisiana

U.S. EPA Method 300.0 describes the use of ion chromatography (IC) with a Dionex IonPac AS4A anion exchange column, a carbonate/bicarbonate eluent, and suppressed conductivity detection for the determination of inorganic anions in environmental waters, such as drinking water, wastewater and aqueous soil extracts. The scope of the method allows an optional column to be used, provided that comparable resolution of peaks is obtained and method QC requirements can be met. This paper describes the use of a new anion exchange column for the routine determination of common inorganic anions in environmental waters. The IonPac AS14A provides the speed and efficiency of the AS4A-SC column, along with improved separation of fluoride from the column void volume (water dip) and better overall separation selectivity. The potential interferences, linear range, method detection limits, and analyte recoveries obtained with this column for a variety of environmental samples is described.

Solid Phase Microextraction for Metal Speciation
Mester, Zoltan (Univ. of Waterloo, Waterloo, Ontario, Canada); Janusz B. Pawliszyn.
PITTCON 2000, 12-17 March 2000, New Orleans, Louisiana

The authors have examined the potential of solid phase microextraction (SPME) technique for metal speciation. Head-space SPME technique was studied for the determination of arsenic, mercury, and lead species using direct extraction or different derivatization methods (ethylation, phenylation). The quantification was carried out using gas chromatography / mass spectrometry (GC/MS). In-tube solid phase microextractions was applied for the extraction of non-volatile metal species. A schematic shows the in-tube solid phase microextraction system coupled with HPLC separation arid electrospray MS detection. It is essentially an open tube capillary, coated on the inside with a suitable extraction polymer, connected to the HPLC system in place of the sample introduction loop. In-tube SPME-HPLC was used to determine different seleno-aminoacids (Selenomethyonine, Selenoethionine), organo-arsenic species (Mono- and Dimethylarsenic acid, Arsenobetain, Arsenocholine), and Organolead compounds. Electrospray mass spectrometer (ES/MS) was employed for the detection of metal species.

Dual Sampling High-Speed GC Monitoring of VOC Degradation in a Bioreactor
Borgerding, Anthony J. (Univ. of North Dakota, Grand Forks); Robert W. Current; Evguenii I. Kozliak.
PITTCON 2000, 12-17 March 2000, New Orleans, Louisiana

HSGC with cryofocussing injection was used to monitor a fiber-based bioreactor system for the removal of VOCs from air. Two bacterial strains, Pseudomonas fluorescens Y2 and Pseudomonas putida, were immobilized on nylon fiber mats and used to degrade styrene and toluene. Using a dual sample loop system, 0.785 mL samples were taken on-line from a total gas flow of 800 ml/min by pulling 25 ml/min with a vacuum pump. Loop samples taken alternately from the gas flow before and after treatment by the bioreactor are then sent to the cryofocussing injector of the HSGC and analyzed with separation times of less than 20 seconds. By analyzing first the flow into the bioreactor followed immediately by analysis of the air that had passed through and been cleaned, the percent removal of analytes from air was determined. Both remediated and unremediated air could be analyzed together in less than one minute. The analytical system was effective only in monitoring nonpolar analytes. Because of the high water content of the air required to grow the bacteria, a Nation dryer was installed between the sample loops and the cryofocussing injector of the high-speed GC to prevent freezing. Polar analytes such as ethyl acetate were removed along with water by the dryer, preventing them from being effectively analyzed. For toluene and styrene, the analytes studied in this paper, there was no loss due to the Nation dryer. Reproducibility and the possibility for analyte to carry over from one analysis to subsequent ones was determined by alternately measuring a standard sample and a blank.

This dual sampling HSGC system was used to study the biodegradation of styrene and toluene in the bioreactor. Samples were taken every minute for a period of 90 minutes. Approximate removal rates were 25% for styrene, and 10% for toluene. Concentration fluctuations were observed when analyte and bioreactor properties were modified during the period over which the system was monitored.

High Speed Field Screening of MTBE and BTEX in Water Using Membrane Introduction Mass Spectrometry (MIMS)
Bauer, Scott (MIMS Technology Inc.); Harold K. Brown.
PITTCON 2000, 12-17 March 2000, New Orleans, Louisiana

Abstract not available.

Development and Evaluation of a Portable Spectro-Electrochemical Sensor
Stegemiller, Michael L. (Univ. of Cincinnati, Cincinnati, OH); William R. Heineman; Carl J. Seliskar; Thomas H. Ridgway.
PITTCON 2000, 12-17 March 2000, New Orleans, Louisiana

The work described here is based on an optically transparent electrode (OTE) consisting of an indium-tin oxide (ITO) layer on a glass slide coated with a sol-gel derived charge selective film. Light is coupled into the slide through a prism in such a way that total internal reflection is achieved. For an analyte to be detected, it must partition through the charge selective film and undergo electrolysis at the applied potential; the analyte and its electrolysis product must have different spectral characteristics. In response to the need for small and portable sensors, a new prototype sensor was developed. A fiber-coupled blue LED provides a suitable light source. Several optical bandpass filters were evaluated for use with the LED to improve the large bandwidth associated with blue LEDs. The fibers are held in place with a "chuck" made out of PVC tubing. The chuck is then held at fixed angles to the prism face to allow for total internal reflection to be attained. The majority of the sensor is made out of black delrin. This includes a base piece to hold the ITO covered slide, a solution chamber piece (chamber volume less than 1 mL) that allows for solution to flow through the detection area, and a top cover piece to hold the incoming fiber and the detector. A small photodiode provides a simple and inexpensive detector. Sensor performance was evaluated with ferrocyanide as a representative analyte, and a composite film of PDMDAAC-SiO2 (PDMDAAC = poly(dimethyldiallylammonium chloride)) was used as the charge selective film. This composite film preconcentrates anions at the surface of the ITO slide. Quantification of ferrocyanide was accomplished in a complex sample matrix.

Development of a Total Internal Reflectance Spectroelectrochemical Sensor Utilizing Paraquat as the Target Analyte
Clager, Michael R. (Univ. of Cincinnati, Cincinnati, OH); William R. Heineman; Carl J. Seliskar.
PITTCON 2000, 12-17 March 2000, New Orleans, Louisiana

A spectroelectrochemical sensor for paraquat (methyl viologen) is being developed that consists of a planar substrate of glass coated with a thin layer of indium tin oxide (ITO), which functions as the working electrode. Over the working electrode surface is a controlled thickness layer of sol-gel encapsulated Nafion. The purpose of this sol-gel layer is to concentrate paraquat into the sensing region while excluding potentially interfering anions. Sensing is accomplished by launching light into the glass substrate at an angle such that several internal reflections occur in the sensing region. At these reflection points, an evanescent wave is generated. This is where the optical sensing occurs.

Soil Screening for Polycyclic Aromatic Hydrocarbons
Zhang, Hongyan (Ohio Univ., Athens); Anthony Andrews.
PITTCON 2000, 12-17 March 2000, New Orleans, Louisiana

Solvent microextraction (SME) was investigated as a fast, simple, safe, inexpensive alternative method to conventional liquid-liquid extraction. The technique uses the principle of liquid-liquid extraction applied to small volumes. Although polycyclic aromatic hydrocarbons (PAHs) have limited solubility in water, with some amount of organic modifier added, water can be used as an extraction solvent for simple screening purposes to determine the extent of PAH contamination. SME and solid-phase microextraction in conjunction with a water-based partial extraction have been used as preliminary screening procedures. The PAHs were the measured by GC. Experimental conditions and results are discussed, and a comparison is made between a conventional flame ionization detector and a pulsed-discharge helium ionization detector.

A GC/MS Method Used for the Detection and Identification of More Than 567 Potential Pesticide and Suspected Endocrine Disrupters in Complex Matrices
Meng, Kai (Agilent Technologies); Phillip L. Wylie; Michael J. Szelewski.
PITTCON 2000, 12-17 March 2000, New Orleans, Louisiana

Previous analytical methods for analysis of endocrine disrupters were narrowly defined and/or based on an out-of-date technology. Even with the specificity of GC/MS, it is still a very difficult and time-consuming task to identify all pesticides and endocrine disrupters in complex matrices such as food. A GC/MS method and a database have been developed to screen for over 567 pesticides and suspected endocrine disrupters. A technique called retention time locking (RTL) ensures the analyte retention times between and among GC systems match those in the database. After a GC/MS screening analysis, results are automatically compared against entries in the library using small retention time windows (for example, 0.3 min). The software uses a target ion and three qualifier ions for each library entry. The possible matches are limited to the library entries that have the retention times within the small 0.3-minute window. The small time window makes the database matching much quicker and, most importantly, cuts down false positives.

Fast Sampling and Analysis of Volatile Organic Compounds in Indoor Air by Solid-Phase Microextraction/Field-Portable GC
Jia, Mingyu (Univ. of Waterloo, Waterloo, Ontario, Canada); Jacek Koziel; Janusz B. Pawliszyn.
PITTCON 2000, 12-17 March 2000, New Orleans, Louisiana

Solid-phase microextraction (SPME) was used to sample five target VOCs (benzene, toluene, ethylbenzene, xylenes, and hexane) in indoor air. Concentrations of target VOCs were determined using SPME with a poly(dimethylsiloxane)/ divinylbenzene (PDMS/DVB) porous coating and one minute exposure time. A portable SRI 8610C GC, equipped with a series of devices--a photoionization (PID), a flame ionization (FID), and a dry electrolytic conductivity (DELCD) detector--was modified and used for onsite field analysis. The method detection limits for the target VOCs in air ranged from 10 to 20 parts-per-trillion (ppt). NIOSH method 1501 was used to validate SPME air sampling. Compared to the liquid-phase PDMS fiber, PDMS/DVB fiber had much higher sensitivity and capacity for extracting VOCs.

Speciated Isotope Dilution Mass Spectrometry: Application to Mercury Speciation
Boylan, Helen M. (Duquesne Univ., Pittsburgh, PA); Robert C. Richter; Howard M. Kingston.
PITTCON 2000, 12-17 March 2000, New Orleans, Louisiana

The trend in environmental analysis is proceeding from total elemental analysis to the analysis of individual species. The technique of Speciated Isotope Dilution Mass Spectrometry (SIDMS) has been successfully applied to the speciation of different oxidation states of chromium. The researchers then applied SIDMS to mercury species, both inorganic and organic forms, with special emphasis on methylmercury. SIDMS is a definitive technique for species analysis that has the ability to track and deconvolute transformations among species during sample preparation and measurement processes. The method involves spiking the sample with isotope-labeled species; each species of interest is labeled with a unique isotope. The species are then separated, and isotope ratios are measured using ICP-MS. The authors discuss parameter optimization of the separation and analysis steps involved in SIDMS.

Evaluation of Mobile Phases for LC-ICP-MS Speciation of Arsenic Compounds in Diverse Matrices
Akinbo, Olujide T. (Research Triangle Inst., Research Triangle Park, NC); Reshan A. Fernando; James H. Raymer; Edo D. Pellizzarri.
PITTCON 2000, 12-17 March 2000, New Orleans, Louisiana

One of the major factors in developing a chromatographic method for elemental speciation is the selection of suitable mobile phase that will elute the analytes in reasonable time. Added to this requirement is the need for the mobile phase to be compatible with the mode of detection without degrading the sensitivity of the detector. An assessment of the literature suggests that the authors have used either the carbonate or phosphate buffers as mobile phases for speciation arsenic compounds and that the selection of mobile phases for LC-ICPMS is primarily influenced by factors with direct implications on the chromatographic separation of the analytes and plasma performances only. The effect of salt deposition on the sampling and schemer cones of the ICPMS cannot be overlooked since these affect the ion transmission and could cause a degradation of analytical performance of the ICPMS. The authors present the results of a study in which four mobile phases--carbonate, phosphate, acetate, and TRIS-acetate buffers--were evaluated for long-term application to speciation of arsenics in diverse matrices.

Real-Time Analysis of Trace Elements in Synthetic Silicate and Limestone Stream Sediments Soil Samples Measured by Laser Induced Breakdown Spectrometer
Lu, K.T. (Atomic Engineering Corp., Gaithersburg, MD); Dennis Baba; Thomas Leffler.
PITTCON 2000, 12-17 March 2000, New Orleans, Louisiana

In situ detectors may be affected by calibration problems because of the lack of reliable library data for environmental matrix effects, such as soil matrix, moisture, pressure, and so forth. The commonly used practice of precalibrating single species detectors before their use in the field does not stand up to the challenge presented by field conditions. Reliable calibration procedures must be developed to determine the detection limits of analytes in unknown and mixed samples in real time and under field conditions. The researchers have developed a software able to perform real-time calibration and determine the detection limits of metal element concentration in real time and under field conditions. The ACAS software offers improvement in both speed and ease of use over the early AMCS developed by Atomic Engineering Corporation (AEC). The software has been used to produce two databases: limestone stream sediments soil samples and a trace elements database in synthetic silicate soil samples. These databases were then used as precalibrated standards to determine detection limits of metal element concentrations in synthetic silicate soil sample and limestone stream sediments soil samples by laser-induced breakdown spectroscopy. It is essential to calibrate the detector with databases under field matrix conditions because the sensitivity of detection limit of certain metals is masked by the environmental matrix effect in the soil sample generated by the laser-induced plasma. The databases with field matrix conditions were created using the ACAS Spectral Analysis module. The database files were determined by calibrating selected fingerprints of the analyte relative to the AEC's reference database and to the total background base sample fingerprints. The accuracy of the results depend on the selection of the finger prints of the analyte as well as on the selection of the finger prints of the background base sample finger prints. These database files can be loaded by the search program when needed to be compared against similar files to determine the detection limit. The detection limits of analyte concentrations are determined by the Concentration Analysis Module, in which all files with similar structure are organized in groups so they can be loaded, searched, and analyzed in a few steps with reference to the database created earlier. The combination of improved software and the reference databases make the real-time analysis of trace elements (Be, Ba, Sr, Cr, Cu, Pb, Ti, Fe, Zn, Mn, etc.) in soil possible under field conditions.

Side-By-Side Comparison of Small, Hand-Held Ion Mobility Spectrometers and Surface Acoustic Wave Devices
Davis, Dennis M. (U.S. Army Edgewood Chemical Biological Center, Aberdeen Proving Ground, MD); Charles S. Harden; Vincent M. McHugh; Donald B. Shoff.
PITTCON 2000, 12-17 March 2000, New Orleans, Louisiana

The U.S. DoD has entered into a significant development program aimed at production of small, unobtrusive chemical warfare (CW) agent detectors. Side-by-side evaluations of prototype Ion Mobility Spectrometry (IMS) and Surface Acoustic Wave (SAW) field instruments have been performed at the U.S. Army Edgewood Chemical Biological Center. Among the devices evaluated were small field prototype instruments that fit in the palm of a human hand and weigh about 2 pounds. The evaluators undertook to describe the relative performance characteristics of devices based on the two technologies in experiments consisting of exposures to the same sample conditions at the same time; hence, ambiguities resulting from exposures to different analyte concentrations, water vapor concentrations, and sample gas temperatures would be eliminated. Analytes used in these evaluations included toxic and non-toxic organophosphorus compounds, organosulfur compounds, hydrogen cyanide, and cyanogen chloride. Performance was tested in relative humidity conditions of 80 to 90%, because conditions of high temperature and humidity are generally problematic for hand-held detection systems. The prototype devices were simultaneously exposed to analyte vapors in air and in mixtures of air and other substances that were known to cause undesirable responses in both IMS and SAW devices. Ion mobility spectra were compared with SAW crystal frequency shifts for each of the analyte / interference / water vapor mixtures. Results noted include signal-to-noise near limits of detection, response times, recovery times, ability to distinguish analytes by group and by type within a group, and ability to distinguish between analytes of interest and potentially interfering substances. This paper reviews the state of the art in the development of small, hand-held field detection devices based on IMS and SAW technologies.

Investigation on Microsensors for In-Situ Characterization of Mixed Waste Using Steady-State Fluorescence Polarization
Yan, Yuan (Univ. of South Carolina, Columbia); H. Li; Michael L. Myrick.
PITTCON 2000, 12-17 March 2000, New Orleans, Louisiana

The authors discuss their efforts to develop steady-state fluorescence polarization (SSFP) techniques that selectively retard depolarization effects for small molecules in fluid solution without sacrificing the inherent sensitivity of fluorescence spectroscopy by the introduction of micelles. In their research, fiber optics have been used to conduct the excitation source from an Coherent Argon laser to the sample and get the emission back to a CCD camera for recording. The results show that sub-part-per-billion sensitivity, which is much better than the sensitivity of most fluorescence polarization methods currently used, can be achieved for most analytes by the instrument. Some discussions on SSFP for small molecules on the instrument also are presented.

UV-VIS Alternative Method for the Determination of Metals in Soils
Boudenne, Jean-Luc (Univ. De Provence, Marseille, France); Frederic Theraulaz; Bruno Coulomb; Christophe Brach-Papa.
PITTCON 2000, 12-17 March 2000, New Orleans, Louisiana

A new procedure is proposed to reduce the cost and the duration of analysis by the simultaneous determination of different metals (Fe, Cu, Ni, Zn, and Pb) by direct or indirect UV-VIS analysis of EDTA extracts. Fe-EDTA complexes are detected directly in the UV range, and speciation of different forms of Fe is possible. Other metals require a two-step procedure. First, the metals-EDTA complexes are submitted to a photo-oxidation step with a UV deuterium lamp, then they are complexed again with another reagent whose nature depends on the metals of concern. The UV-VIS spectra obtained are computed with a multiwavelength deconvolution procedure to achieve the selectivity and sensitivity of the method. This method has been validated by comparison of results given by the atomic spectroscopy analysis, and a good correlation coefficient has been obtained. This analytical procedure can be automated for field determination of metal ions in soils.

Development of a New Laser-Induced Fluorescence (LIF) Spectrometer for Environmental In-Situ Analysis of Water and Soils
Schultze, R.H. (Inst. fuer Physikalische Chemie, Erlangen, Germany); E. von der Heide; T. Hengstermann; H.G. Lohmannsroben; P. Wagner.
PITTCON 2000, 12-17 March 2000, New Orleans, Louisiana

For in situ detection and analysis of fluorescence tracers and petroleum products (oils) in water and soils a mobile and flexible LIF-spectrometer was developed called OPTIMOS, the Oil Pollution Transportable Independent Monitoring System. OPTIMOS is designed for use in the field. The full version consists of a Nd:YAG/dye-laser combination, providing a wide range of excitation wavelength, and an ICCD multichannel detection system. In the case of the simplest configuration of OPTIMOS a UV-LED is employed as light source, and a PMT or a photodiode as detector is used. This paper addresses characterization of different configurations of the OPTIMOS system, evaluation of analytical parameters for in situ detection of fluorescence tracers in water and in situ analysis of oil-contaminated soils, and construction, characterization, and employment of different LIF sensors, e.g. a lance for bulk soil analysis or a sensor head for applications in a penetrometer for subsurface measurements.

Public Access to Air Toxics Data: the Tosco-Rodeo Oil Refinery Air Quality Monitoring Project
U.S. EPA Region 9 website, 11 May 2001

The Tosco-Rodeo Oil Refinery in Contra Costa County, California, has installed three kinds of air monitors: FTIR, UV, and laser. All are "open path monitors," meaning they measure ambient air pollutants occurring over a 1,000-meter light beam path. Monitors are located along both the north and south fence lines to scan for 38 air pollutants, including some chemicals defined as hazardous in the Clean Air Act, Section 112. The monitors operate every five minutes, 24 hours a day, seven days a week and can generate millions of data points in a year. This website offers operating information on the fenceline monitoring systems in use at the site - http://www.epa.gov/region09/features/tosco/monitoring.html

Optical Remote Sensing Devices: Some Manufacturers and Consulting Firms
Fenceline Monitoring Homepage of the Shoreline Environmental Alliance

In July of 1997, The Tosco Oil refinery in Rodeo, California, completed the installation of its new fenceline monitoring system after an incident in which hazardous gases were released to the surrounding neighborhood. This monitoring network, which incorporates ten optical remote sensing devices, is designed to detect and track concentrations of a wide range of hazardous gases, and to provide early warning to the surrounding communities in the event of a chemical emergency. The Shoreline Environmental Alliance (SEA) has developed a website to keep the public informed of developments in the monitoring effort. SEA has devoted one page of its site to a list of commercially available optical remote sensing devices with addresses and links to the companies who manufacture open-path monitoring equipment, as well as to environmental consulting firms who have experience in operating this equipment. SEA has attempted to include as many companies in this field as could be located, not just those that have provided service to the Tosco/Unocal Refinery monitoring effort. More information: http://sea.enviroweb.org/mfgrs.html

Open-Path Monitoring with Ultraviolet or Infrared Light
Canadian Environmental Solutions. Industry Canada, Environmental Affairs Branch. 25 Jul 2001

Optical remote sensing for gaseous pollutants at ground level is an advancement equivalent to satellites for monitoring the earth. No longer does the gas needing to be detected have to be sampled or make contact with a surface of a detector. Various methods of remote sensing have the ability to identify and quantify gaseous compounds of interest up to 1 km away from the instrument. The scientific methods used encompass radiation absorption and scattering. A very basic description of the principle of operation of this technology is that a light beam is directed, potentially in several directions, into the ambient air. As the light beam intersects the compounds of interest, a unique spectral signature is detected for each compound. From each signature the quantity of gas present in the beam is derivable. At minimum, this technology complements gas point monitors. At maximum, this technology replaces gas point monitors. Spatial coverage is greatly enhanced, sensitivities are equivalent or better, capital expenditures are low along with maintenance costs, installation is straightforward, existing staff is conveniently trained to operate the instruments and disseminate the data. Applications cover the areas of fenceline monitoring, industrial hygiene, facility safety, and process control. Provider: SCI-TEC Instruments Inc., 1503 Fletcher Road, Saskatoon, Saskatchewan, S7M 5S5, Canada. http://strategis.ic.gc.ca/SSG/es30972e.html

Air Quality Monitoring Technology Licensed
Aerospace Technology Innovation, Vol 5 No 4, Jul/Aug 1997

Technology originally developed for monitoring atmospheric air quality now is being used to help U.S. industries reduce smokestack pollution. A remote gas sensor with NASA technology could detect industrial pollution with a "fence" system that would allow the sensor to see around an area with help of mirrors. NASA has worked with MERCO Incorporated, Golden, Colorado, to jointly develop and commercialize the technology through a patent license agreement. The Sensor Systems Branch at Langley Research Center will transfer its fast-response, non-mechanical, remote gas-sensing technology for monitoring gaseous pollutants emitted from petroleum refineries and chemical manufacturing facilities to MERCO. The technology originally was developed to measure gases in the Earth's atmosphere from aircraft and satellite platforms, and its improved design makes it attractive for many Earth-based monitoring applications. Called the Gas Filter Correlation Radiometer, the device possesses many distinct advantages over conventional gas sensors such as remote sensing capability, area source monitoring, higher reliability, faster response and more compact design. The Mid-Continent Technology Transfer Center facilitated the agreement. MERCO anticipates rapid commercialization of the instrument. Contact: MERCO, Inc., 1667 Cole Blvd. Building 19, Suite 400, Golden, CO 80401; (303) 274-9686.

SBIR Leads to Plant Fluorescence Sensor
Aerospace Technology Innovation, Vol 9 No 3, May/Jun 2001

The work of a Billerica, Massachusetts, company funded through the Small Business Innovation Research (SBIR) Program at NASA Stennis Space Center can help growers assess the help of crops. Aerodyne Research, Inc. has successfully developed the Plant Fluorescence Sensor (PFS), a real-time sensor that passively monitors plant health by remotely sensing plant responses related to the fundamental process of photosynthesis. As NASA's lead center for the commercialization of remote sensing technologies, the NASA Earth System Science Office (ESSO) at Stennis incorporates the technology of remote sensing into its efforts. One focal area of research is the pre-visual sensing of unhealthy, or stressed, plants. Aerodyne's development of the PFS through the SBIR Program is in response to one of the ESSO's challenges. Aerodyne designed and built the PFS as a robust sensor of sunlight-excited chlorophyll fluorescence. It provides for the real-time, in situ remote sensing of photosynthetic activity in plants. This sensor, which operates as a Fraunhofer line discriminator, detects light at the cores of the lines comprising the atmospheric oxygen A-band and B-band, centered at 760 nanometers (nm) and 688 nm respectively. Fraunhofer lines identify the spectral regions where little or no solar radiation reaches the surface of Earth, providing an area free of solar background interference. These bands also correspond to wavelengths in the red and far-red chlorophyll fluorescence bands. The intensity and spectral band shape of chlorophyll fluorescence in green plants has been linked to the physiological status of plants, thus providing a good indicator of general plant health. Aerodyne Research sees a market for the Plant Fluorescence Sensor as a passive remote monitor of plant health. Applications include agriculture, forestry, and environmental monitoring of soil remediation projects. Aerodyne has elected to retain title to this invention, which has been credited to Dr. Paul Kebabian. For more information about the Plant Fluorescence Sensor, contact Dr. Herman Scott at Aerodyne Research, 978/663-9500, ext. 267. More information: http://nctn.hq.nasa.gov/innovation/6-sb-pfsensor.html

Using Ternary Diagrams to Characterize Transport And Attenuation of BTX
Lipson, D.; D.I. Siegel, Blasland, Bouck & Lee Inc., Syracuse, NY.
Ground Water, Vol 38 No 1, p 106-113, 2000

Dissolved aromatic hydrocarbon concentration data commonly are interpreted only within the context of regulatory maximum allowable concentration levels. This paper illustrates how ternary diagrams can clearly characterize from routine monitoring data the physical and chemical controls governing the fate and transport of aromatic hydrocarbons in ground water. The results of type mathematical modeling experiments for BTX solute transport show that changes in BTX concentrations, when plotted as proportions on ternary diagrams, form clear trajectories documenting major attenuation or transport processes. Ternary diagrams can be used to determine from monitoring data whether proposed natural attentuation processes are in fact present and the efficiency of different remediation efforts used to clean up leaking underground storage tank sites.

Bound Pesticide Residues in Soils and Plants and Their Determination
Tiryaki, O.; P. Aysal, Turkish Atomic Energy Authority, Ankara Nuclear Research and Training Center, Ankara,Turkey.
Turkish Journal of Nuclear Sciences, Vol 26 No 2, p 43-60, Dec 1999

The environmental significance of pesticide residues in soil and plants was examined in two types of residues: those residues that are extractable with solvents, and those that are not extractable with solvents. The extent of bound (non-extractable) residues varies with the plant and pesticide involved and generally increases with time after treatment. Bound pesticide residues have been detected in the organic matter fractions of soil (i.e., humic acid, fulvic acid, and humin). Several studies have shown that lignin, hemicellulose and pectic polysaccharide are the major bound residues fraction of pesticide in plants. Attempts have been made to extract bound pesticide residues by a variety of methods. Drastic extractive procedures destroy the structure of soil or plants often result in the destruction of the identity of bound residues. The High Temperature Distillation (HTD) and Supercritical Fluid Extraction (SFE) techniques may provide possible means for extraction and identification of bound residues.

Speciation of Inorganic Sulphur in Aquifer Sediments Contaminated by Landfill Leachate Using Chemical Extraction Techniques
Crouzet, C.; M.A.M. Kedziorek; R.S. Altmann; A.C.M. Bourg, Laboratory of Analytical, Bioinorganic and Environmental Chemistry, Univ. of Pau, Helioparc Pau-Pyrenees, Pau Cedex, France.
Environmental Technology, Vol 21 No 3, p 285-296, 2000

This paper describes a protocol for determining the distribution of sulphur forms in aquifer solids. A series of single parallel extractions and two-step treatments derived from a combination of previously described extractions were tested on simple Fe and/or S minerals (goethite, alkageneite, hematite, ferrous sulphide, pyrite, flower elemental sulphur and ferrous sulphate). Monosulphides were extracted with hot HCl. Iron disulphides were determined using a Cr(II) digestion after preliminary elimination of monosulphides, elemental sulphur, and sulphates with HI. Sulphate was extracted by NaH₂PO₄ followed by HI treatment. Elemental sulphur was estimated from differences between total sulphur and the fractions quantified above. The protocol was applied to analysis of reduced and oxidized sediments from a well-characterised sandy aquifer system downgradient from the Danish Vejen landfill, and the results are described.

BYU Researchers Create Fluorescent Molecules That Detect Metal Pollutants in Water, Waste
Brigham Young University News Release, 23 Jul 2001

A team of Brigham Young University researchers has developed synthetic molecules that glow in the presence of certain metal pollutants. BYU researchers devised the molecules as an improved method of detecting and monitoring increased metal levels in the environment caused by mining, smelting, fossil fuel combustion, and industrial use. The research goal is to create a sensor that continually measures metal in a sample of water as it flows by, making it easier to respond to contamination problems more quickly. The team designed and created the molecules in the laboratory. The molecules respond to zinc in the presence of ultraviolet light, and can also indicate the presence of mercury and cadmium. To detect metals such as zinc in water, BYU researchers first created compounds that seek out and bind to metal ions--those atoms with extra electrons. Next, they created small molecules that attach to the metal-binding compounds. The small molecules reveal the presence of bound metal ions by acting as fluorescent "reporters" when ultraviolet light is shined on them, the "reporters" glow brightly. If no metal ion is bound, the compounds remain dark. The color of the glow depends on the type and concentration of the metal ions present. Plans are under way to develop a device that will allow industrial plants and water treatment facilities to track the concentration of metal ions in water and wastestreams over time. The lead researcher was emeritus professor of chemistry Jerald S. Bradshaw. Assisting Bradshaw and Savage were BYU researchers Reed M. Izatt, R. Todd Bronson, Saowarux Fuangswasdi, Sang Chul Lee, and collaborator Krzysztof E. Krakowiak.

Using Stable Isotopes of Carbon and Nitrogen as In-Situ Tracers for Monitoring the Natural Attenuation of Explosives
Miyares, P.H.; C.M. Reynolds; J.C. Pennington; R.B. Coffin; T.F. Jenkins; L. Cifuentes, U.S. Army Corps of Engineers, Cold Regions Research and Engineering Laboratory (CRREL).
CRREL Special Report 99-18, 26 pp, Dec 1999

The use of carbon and nitrogen stable isotope measurements from TNT was examined as a possible tool for monitoring the natural attenuation of TNT. Incubation studies of spiked soil samples were conducted. The concentration of TNT and the del () values for 13 C and 15 N of the soil and of TNT were measured with time. Results indicated that no measurable changes in the 13 C or 15 N value of the soil or 13 C values for TNT could be detected as the concentration of TNT decreased. Measurable changes in the 15 N value of TNT with changing TNT concentration suggested a possible monitoring route. Field studies using both soil and ground-water samples support the laboratory finding that changes in the 15 N for TNT extracted from ground water could be detected in samples collected at different points along transects at the Louisiana Army Ammunition Plant and that no measurable change in the 13 C values for soil or TNT could be seen.

More information: http://www.crrel.usace.army.mil/techpub/CRREL_Reports/reports/SR99_18.pdf

Evaluation of H.E.L.P. Mate 2000 for the Identification and Quantification of Petroleum Hydrocarbon Products
Hewitt, Alan D., U.S. Army Cold Regions Research and Engineering Laboratory (CRREL), Engineer Research and Development Center (ERDC), Hanover, NH.
ERDC/CRREL TR-00-20, 20 pp, Sep 2000

The H.E.L.P. Mate 2000 (HM 2000) is a spectrophotometric instrument developed for use with the Hanby Test Kits to rapidly assess of total petroleum hydrocarbon contamination (TPH) in environmental matrices onsite. This spectrophotometer is designed to remove the subjectivity associated with the present visual method of analysis, and to eliminate the requirement for prior knowledge of the type of petroleum hydrocarbon contamination present at a given site. Both the HM 2000 and the current visual method of analysis measure the color that is produced by the Friedel-Crafts reaction with the aromatic hydrocarbons present in petroleum-based fuels, oils, and solvents. Laboratory and field studies were used to evaluate the HM 2000. Different results were obtained, depending on the type of sample matrix. In general, the HM 2000 was more accurate and precise for soil samples than for water samples. However, in comparison to the visual method, the HM 2000 was neither as accurate nor did it offer any qualitative advantages.

More information: http://www.crrel.usace.army.mil/techpub/CRREL_Reports/reports/TR00-20.pdf

Field Gas Chromatography/ Thermionic Detector System for On-Site Determination of Explosives in Soils
Hewitt, Alan D.; Thomas F. Jenkins; Thomas A. Ranney, U.S. Army Cold Regions Research and Engineering Laboratory (CRREL), Engineer Research and Development Center (ERDC), Hanover, NH.
ERDC/CRREL Technical Report TR-01-9, 29 pp, May 2001

Onsite determination of nitroaromatic, nitramine, and nitrate ester explosives compounds in soils was performed using a field-portable gas chromatograph (GC) equipped with a thermionic ionization detector (TID) selective for compounds with nitro-functional groups. Soil samples were extracted with acetone. A 1-µL volume of the filtered soil extract was manually injected into the GC, allowing for the rapid qualification and quantification of the suite of explosives that often coexist in soils at military training facilities and other defense-related sites. Good agreement was established for the concentrations of several explosives analytes when this method of analysis was compared to either high-performance liquid chromatography (Method 8330) or GC electron capture (Method 8095) analysis. Comparisons were performed for sample extracts and for soil subsample replicates distributed for onsite preparation and analysis during a field verification test performed under the auspices of the U.S. Environmental Protection Agency 's Environmental Technology Verification (ETV) Program.

More information: http://www.crrel.usace.army.mil/techpub/CRREL_Reports/reports/TR-01-9.pdf

Non-Intrusive Liquid Level Detection Technology
Hanford Environmental Restoration Project Innovative Technology Opportunities, Technology Deployment Fact Sheet, 2 pp, 1999

Non-Intrusive Liquid Level Detection technology (NLLDT) uses infrared thermography to assay tanks and equipment for the presence of liquids. As such, liquid level information in tanks or equipment can be obtained for use in planning decommissioning activities. The canyon deck of the 221-U Facility contains numerous vessels and equipment. The NLLDT System was deployed to assay selected equipment for the presence of liquid. This information was gathered in support of the Canyon Disposition Initiative (CDI) Project. The CDI Project is analyzing alternatives for the final disposition of the five large chemical processing facilities (canyons) at the Hanford Site. The 221-U Facility serves as the pilot facility for the CDI Project. Non-intrusive liquid level detection technology is the use of infrared thermography coupled with either normal ambient temperature changes or local, low-level heating or cooling to passively and non-intrusively detect liquids in tanks and piping. Specifically, infrared imaging cameras are used along with specialized testing procedures to exploit physical property variations in the tanks/pipes and contained liquid and air to produce temperature contours of images that identify the liquid levels. Infrared thermography is the process of converting heat emitted from an object into a visible dynamic television-like picture. The technology provides a non-intrusive method that can determine presence/absence of liquids in congested facility equipment. Visual inspection, boroscopic visual inspection, and dipsticks are the baseline technologies for determining the presence or absence of freestanding liquids in facility equipment. Liquid detection in pipes is accomplished by finding low points and tapping the pipe for inserting sampling parts. The NLLDT was deployed to detect liquids in a number of selected targets. More information: http://www.hanford.gov/techmgmt/99accomplish/55.PDF

Leak Detection 2000 CD-ROM
Ken Wilcox Associates, Inc., Grain Valley, MO. 2000

This CD-ROM contains summaries of over 300 leak detection methods from 100+ vendors and is searchable by vendor or method type. It holds third-party evaluation procedures from the U.S. EPA, KWA, MRI, and other organizations, and full copies of third-party certifications from leading vendors. Also present are those parts of the U.S. Code of Federal Regulations pertaining to underground storage tanks and leak detection. Several kinds of tank inventory-calculating software are provided.

Optimisation of the Experimental Conditions of a New Method, Based on a Quartz Crystal Microbalance, for the Determination of Cyanide
Gomes, M.T.S.R.; A.A.F. Silva; A.C. Duarte; J.A.B.P. Oliveira.
The Analyst, Vol 122 No 10, p 1139-1141, 1997

Two procedures for cyanide determination are described. A modified simplex algorithm was used to optimize the experimental conditions with regard to solution pH, temperature, and N2 flow rate. Sensitivity increases of 1.5 and 1.7 were obtained for the two procedures with 27 and 12 experiments, respectively. Under the optimized conditions, the calibration graphs were linear for 0.05-0.5 and for 0.24-0.86 ppm cyanide for the two procedures.

Techniques for the Determination of Cyanide in a Process Environment: a Review
Barnes D.E.; P.J. Wright; S.M. Graham; E.A. Jones-Watson.
Geostandards Newsletter: The Journal of Geostandards and Geoanalysis, Vol 24 p 183-195, 2000

The determination of cyanide in various forms is important for industrial processes as well as for environmental investigations and monitoring associated with these processes. The accurate determination of cyanide is difficult for various reasons: depending on the pH of the solution, cyanide is present both in molecular form (HCN) and ionic form (CN-); cyanide is a good complexing reagent and reacts with almost all cations resulting in complexes with widely varying properties, such as stabilities, solubilities, and rates of reaction; and cyanide also breaks down in sunlight and air, so that sampling and sample treatment become very important aspects to consider in the methodologies. During the last fifty years the determination of cyanide has been approached from various angles and a variety of methods have been developed for its determination. This study represents a survey of methods commonly used in industrial laboratories for the analysis of cyanide-containing solutions. The authors provide an overview of the nomenclature often used for the various forms of cyanides and an interpretation of the values resulting from a particular analysis.

Assessment of Different Fluorimetric Reaction for Cyanide Determination in Flow Systems
Miralles, E.; M.D. Prat; R. Compañó; M. Granados, Univ. of Barcelona, Spain.
The Analyst, Vol 122 No 6, p 553-558, 1997

Abstract not available.

On-Line Gas-Diffusion Separation and Fluorimetric Detection for the Analysis of Acid Dissociable Cyanide in Water Samples
Miralles, E.; M.D. Prat; R. Compañó; M. Granados. Univ. of Barcelona, Spain.
The Analyst, Vol 123, p 217-220, 1998

Abstract not available.

Simultaneous Determination of Trace Amounts of Free Cyanide and Thiocyanate by a Stopped-Flow Spectrophotometric Method
Sun, Bianting; B.N. Noller, Univ. of Queensland, Australia.
Water Research, Vol 32, p 3698-3704, 1998

Abstract not available.

Simplifying Cyanide Analysis with Microdistillation
Volmer, Wolfgang; Günter Giesselmann.
American Laboratory News, p 20-22, Jan 2000

In accordance with Sections 13 and 14 of the DIN 84051 standard, this paper outlines the simplification of sample distillation and photometric analysis, and highlights cyanide determination using ion chromatography as a possible alternative. Since 1992, the ad hoc Cyanide Study Group (Wiesbaden, Germany) has been developing a new standard process for the determination of cyanide. The use of ion chromatography or agentometry (instead of photometry) for this purpose has also been examined. The MicroDistiller (Eppendorf - Netheler - Hinz GmbH, Hamburg, Germany) is designed for distillation processes that use a maximum distillate volume of 10 mL. The program-controlled process ensures the separation of the volatile contents of complex substance mixtures. Universal sample-receiving liquids enable the enrichment and separation of solid and liquid samples. All processes in which the volatile components are released chemically (e.g., during cyanide determination) are fully automated. The distillation process takes place using a sample vial and collection vial that are connected via a capillary. Quantitative enrichment of volatile compounds is achieved by placing one or more borosilicate glass frits into the heating vessel. This results in the continuous formation of vapor bubbles during boiling. This compact arrangement means that large-volume micro test tubes and expensive cooling equipment are not necessary. The device is very easy to handle. Up to six samples are placed in the heating positions in sealed, beaded-rim vials. At the same time, the corresponding number of sealed collection vials are placed in the cooling positions. The sample vials and collection vials are connected via a capillary that is inserted through the septum seals of the vials. The desired program is then called up, and the time- and temperature-controlled distillation process begins. Each program has a maximum of four different heating cycles with different temperatures. Each cycle has a heating rate, an individual sample temperature (25-120°C), and a time during which this temperature can be maintained before the next cycle is processed. The cooling temperature of the collection vial within one cycle can be selected by the user (from -9 to +15°C). Individual profiles can therefore be compiled very easily. The simple-to-follow display allows the distillation process to be monitored while it is in progress. Both the cycle in progress and the exact time at which distillation finishes are on permanent display. More information: http://www.iscpubs.com/pubs/al/articles/n0001/n0001vol.pdf