United States
Environmental Protection
Agency
Office of Research and
Development
Washington DC 20460
EPA/600/R-93/079
June 1993
Environmental Research
Laboratory - Athens, GA
1992 Highlights
                                  Status Quo Scenario
                                  increase in
                                  Soil Carbon
                                  1990 to 2030

                                  Key (gC/mA2)

                                     500 tO < 750
                                     750 to < 1000
                                     1000 to < 1250
                                     1250 to < 1500
                                     1500 to < 1750
                                     1750 to < 2000
                                     >= 2000
                                  Athens Environmental
                                  Research Laboratory,
                                  Assessment Branch

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Cover Illustration:
Computer modeling and Geographical Information
Systems support investigations of agriculture's capacity
to serve as a sink or a source for greenhouse gases. One
study from the Lab's Global Change Research Program
indicates that carbon is accumulating in the agricultural
soils of the central United States. The carbon that
accumulates in these sot Is was recently atmospheric
carbon dioxide, a greenhouse gas.

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 The U.S. Environmental Protection Agency's Environmental Research Laboratory at
 Athens, Georgia, conducts and manages basic and applied research to predict, assess, and
 reduce human and environmental exposures and risks from pollutants in freshwater,
 marine, and terrestrial ecosystems and the emission of greenhouse gases to the atmo-
 sphere.

 Athens researchers identifiy and characterize the natural biological and chemical pro-
 cesses in soils, surface waters, and sediments that affect the environmental fate of toxic
 substances, such as solvents, pesticides, or metals. The results are applied in state-of-the-
 art multimedia transport models for predicting and assessing exposures and managing
 environmental pollution problems. A second emphasis involves the development of
 ecological risk assessment methods to evaluate pollutant and other stressor on ecosystems
 such as the Great Lakes, Chesapeake Bay, and large agricultural areas.

 Lab-developed fate and process data and assessment techniques support EPA's environ-
 mental management, regulation, and enforcement activities. Major research areas include
 global climate change, stratospheric ozone depletion, ecological risk assessment, sedi-
 ment quality evaluation, computational chemistry, identification of complex organic
 pollutants, nonpoint source pollution management, agroecosystem monitoring and
 assessment program, multimedia nitrogen impacts, bioremediation, chemical
 remediation, and wellhead protection. The Center for Exposure Assessment Modeling
 distributes models and documentation to environmental managers throughout the world
 by mail and via electronic bulletin board.

 RosemarieC. Russo, Ph.D., Director

 Robert C. Ryans, Technical Information Manager

 Environmental Research Laboratory
 Office of Research and Development
 U.S. Environmental Protection Agency
 960 College Station Road
 Athens GA  30605-2720
 The Office of Research and Development (ORD) conducts in integrated program of scientific research and
 development on the sources, transport and fate processes, monitoring, control, and the assessment of risk and
 effects of environmental pollutants. These activities are implemented through its headquarters, offices,
 technical support offices, and twelve research laboratories distributed across the country. The research focuses
 on key scientific and technical issues to generate knowledge supporting sound decisions today, and to antici-
pate the complex challenges of tomorrow. With a strong and forward-looking research program, less
 expensive, more effective solutions can be pursued and irreversible damage to the environment can be
 prevented.
                                                          Printed on Recycled Paper

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 Atomic Force Microscopy

 Laboratory chemists are applying the new
 technology of atomic force microscopy in
 studies of the processes of oxidation, reduc-
 tion, precipitation, and dissolution of metal
 ions. Atomic force microscopy provides
 scientists, for the first time, with the capability
 to analyze  the structure, morphology, and
 chemical reactivity of environmental surfaces
 at the atomic level of resolution. It is these
 environmental surfaces—mineral, organic and
 microbial in nature—that play a large role in
 controlling the fate of organic and inorganic
 pollutants in the environment.

 Initial work involves confirming surface
 structures of silicates and humic and fulvic
 acids, including observation of features
 important to metal binding processes. Results
 of these examinations of environmental
 processes by atomic force microscopy will
 permit the development of improved models
 for predicting the behavior of pollutants in
 water and soil environments.
 [G. Bailey,  706-546-3307]
New Method for Detecting Azo
Dyes

Research to characterize the structures of
sulfonated azo dyes resulted in the discovery of
a potential means of identifying these com-
pounds in complex structures in ambient
environments. The discovery was made
through the application of secondary ion mass
spectrometry/tandem mass spectrometry.
These dyes comprise more than half of the 57
million pounds of textile dyes used annually in
the United States. Because laboratory studies
have shown that these dyes and their aromatic
amine metabolites, resulting from microbial
transformation in ambient environments, cause
cancer in laboratory test animals, it is impor-
tant to be able to identify and measure the
dyes in aqueous and solid wastes.

Although the study was designed to elucidate
structures of the dyes, an important by-product
was the detection of many fragment ions.
Selective ionization, therefore, shows promise
 as a means of identifying and measuring azo
 dyes and other chemicals in the complex
 mixtures in which they are normally found in
 ambient environments.
 [S. Richardson, 706-546-3199]
 Biosystems Technology
 Development

 A major focus of EPA's Biosystems Technol-
 ogy Development Program has been the
 investigation of bioremediation technologies
 for the in situ treatment of hazardous waste.
 On-going research by Athens scientists and
 others was presented at a meeting in May.
 Research results will provide the basis for
 establishing effective in situ bioremediation
 strategies for treatment of single and mixed-
 chemical wastes often encountered in waste
 sites and for developing scientifically sound
 strategies for treatment at Superfund sites.

 The May forum included discussions of
 research projects on bioremediation of soils
 and sediments contaminated with aromatic
 amines; characterization of microorganisms,
 microbial consortia, and microbial processes
 associated with reductive dechlorination;
 decontamination of PGB-contaminated
 sediments; and effects of metals on the
 anaerobic dechlorination of halogenated
 phenols.
 [J. Rogers, 706-546-3592]
Predicting Organics Fate with
Infrared PRC's

A new approach that applies infrared-spectros-
copy-based property reactivity coefficients was
developed for predicting the environmental
fate of organic chemicals. The potential for
the new system, which is based on Fourier
transforms of infrared spectra, for predicting
hydrolysis rate constants for broad structural
classes has been demonstrated with 41 car-
boxylic acid esters exhibiting a wide range of
structures and reactivities.

Methods for predicting the physical and
chemical constants,  such as hydrolysis rates,

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required for exposure assessm.cn.tas, arc
important to the Agency as it evaluates the
thousands of chemicals for which exposure and
risk assessments arc required. Laboratory
measurements for these chemicals are prohibi-
tively slow and expensive to perform.
IT. Collette, 706-546-3525]
EPA's Earth Systems Modeling
Program

The Athens Laboratory, in cooperation with
the National Center for Atmospheric Research
and the Lawrence Livermore National Labora-
tory, is implementing a new research program
on earth systems modeling as part of the
Global Climate Change Research Program.

The goal is the systematic development of an
earth systems model  that is modular in design,
enables the  exploitation and further develop-
ment of terrestrial biosphcric modeling
components and tropospheric chemistry
relationships, and produces models and
modeling experiments that demonstrate the
feasibility of fully coupled, three-dimensional
models of earth systems.

Major elements of the earth systems model
framework will include atmospheric and ocean
circulation and biogcochemistry models,
cryosphcric models, and biophysical represen-
tations of the terrestrial system including the
hydrologic cycle.
[L. Mulkey,  706-546-3129]
 SAFARI Study of Greenhouse
 Gas Flux

 Three ERL-Athcns chemists studied the
 effects of savanna burning on soil fluxes of
 trace carbon gases (carbon dioxide, methane,
 and carbon monoxide) as part of the Southern
 African Fire-Atmosphere Research Initiative
 (SAFARI) in September. Scientists from 12
 nations participated in the month-long project
 sponsored by the International Geosphcre-
 Biosphcre Program in Kruger National Park,
 South Africa.

 SAFARI involved a wide range of activities,
 including analysis of satellite-generated data,
 collection of air emissions using aircraft, and
 determination of effects of biomass burning on
 soil fluxes of greenhouse gases. The ERL-
Athens studies were conducted in collaboration
with National Aeronautics and Space Adminis-
tration scientists and with a team of terrestrial
ecologists from public and private environmen-
tal organizations in South Africa.

Preliminary analyses of results indicate that
both added moisture and fire greatly enhance
biogenic emissions of carbon dioxide and nitric
oxide from the soils, that a methane sink is not
active in any of the soils  before or after burning
or up to 2 weeks after addition of water, and
that no nitrous oxide emissions occurred. Post-
SAFARI studies will involve the determination
of polycyclic aromatic hydrocarbons and
graphitic carbon in burned biomass residue
collected from the soil surface.

The PAH data will be useful in studies of fire
effects. These studies will be conducted in
collaboration with scientists at the Max Planck
Instut fur Chemie in Mainz, Germany.
[R. Zepp, 706-546-3428]
 Comprehensive Exposure
 Assessment for Agrichemicals

 The Lab launched a comprehensive exposure
 assessment modeling study on the effects of
 agricultural chemicals in surface water and
 groundwater systems and on adjacent terres-
 trial riparian zones.  The project is part of
 EPA's Midwest Agrichemical Surface/Subsur-
 face Transport and Effects Research (MAS-
 TER) Program that combines EPA and U.S.
 Department of Agriculture research require-
 ments in conducting watershed-scale response
 analyses involving complex hydrogeological
 features.

 The Walnut Creek Watershed near Ames,
 Iowa, is the study site. The modeling study
 uses several comprehensive watershed-scale
 tools for the chemical exposure and aquatic
 habitat assessment.  HSPF models surface
 runoff, erosion and stream, channel effects.
 3DFEMWATER/3DLEWASTE simulates
 groundwater response. PRZM-2 integrates the
 field-scale effects. The models will evaluate
 the effects of agricultural production and
 agrichemicals on the ecological and geomor-
 phological status of the watershed. The results
 of these evaluations will be used in the
 MASTER program to develop procedures  for
 assessing pollutant and land management
 effects on the midwestern cornbelt and other
 large areas and for designing an ecologically

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benign management strategy that will be
implemented and demonstrated on the Walnut
Greek site over the next 5 years.
[R. Swank,  706-546-3128]
Support for EPA's Corrective
Action Rule

In response to a request by EPA's Office of
Solid Waste (OSW) for assistance in imple-
menting a Regulatory Impact Analysis (RIA),
three ORD labs assembled a team of experts to
provide information on ground water, surface
water, and atmospheric modeling. The ORD
team produced an organic and inorganic
chemical database, developed specific recom-
mendations for modeling in complex
hydrogeological conditions, carried out com-
plex case study analyses, tested and modified
the computer model used in the RIA, and
performed an uncertainty analysis.

The experts were from the ERL-Athens, the
R.S. Kerr Environmental Research Laboratory-
Ada, and the Atmospheric Research and
Exposure Assessment Laboratory.

The RIA provides a national-scale estimate of
the costs and benefits (that is, reduction in
human and ecological risks) that would result
in the implementation of OSW's proposed
Corrective Action Rule.

The integrated multimedia modeling approach
developed in this effort is being applied to
other important Agency issues, such as the fate
of lead in the environment and cross-media
risk trading.
[D. Brown, 706-546-3546]
EMAP Agroecosystem Study in
North Carolina

The quality of irrigation water supplied by
farm ponds and on-farm wells is being assessed
in a pilot study in North Carolina. Under
EPA's Environmental Monitoring and Assess-
ment Program (EMAP), samples are analyzed
for atrazine, carbofuran, aldicarb, and other
selected pesticides (applied to crops such as
tobacco, peanuts, corn, and cotton) and
nitrates.

In addition, monitoring wells are installed in
the Little Coharie Watershed in a statistically
random pattern. These wells will provide
controlled, reliable ground water data on
pesticides and nitrate that can be compared
with data from existing on-farm wells. The
research effort also will provide an opportunity
to test groundwater threat models for predic-
tive capability on a variety of scales.
[C. Smith, 706-546-3175]
Chemical Characterization of
Hazardous Waste Components

Lab scientists are developing chemical trans-
formation pathway profiles for more than 200
chemicals under consideration in establishing
the Office of Solid Waste's Hazardous Waste
Identification Rule and determining whether
specific waste components are most appropri-
ately modeled using the finite- or infinite-
source modeling methodologies. Profiles
include determination of the processes by
which each chemical will degrade or be
transported, sediment-water distribution
coefficients, and transformation rates for the
listed chemicals (parent) and their transforma-
tion products (daughter) as well.

After analysis of theoretical considerations,
which identify likely daughter products on the
basis of chemical structure, the transformation
rates and equilibrium constants are arrived at
by considering measured values from the
literature, applying computational chemistry
methods, postulating values from chemical
structure, and making laboratory measure-
ments for parameters considered critical to the
Rule's application for chemicals for which
remaining levels of uncertainty are unaccept-
able.

Development of these profiles is possible only
because of the knowledge gained in ERL-
Athens' unique 20-year program in environ-
mental chemical process research.
[W. Donaldson, 706-546-3183]
Environmental Education
Reaches Students, Teachers

The Lab's Environmental Science Education
Program, established in 1991 and managed by
Ms. Kate McDaniel, continued its outreach
activities. Twenty teachers representing
school districts from across Georgia attended
an intensive, 8-day workshop entitled "Envi-

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ronmcntal Chemistry As It Relates to the
Community," cosponsored with the Northeast
Georgia Section of the American Chemical
Society. The teachers learned innovative skills
for enhancing their high school science
courses. Ms. McDaniel participated as a
volunteer instructor in the Presidential Class-
room for Young Americans, a week-long
session for high school juniors and seniors in
Washington DC. The Lab was awarded a
grant for environmental education through the
Agency's Minority Cooperative Education
Program. The grant will be used to support a
Master's Candidate in Environmental Risk
Management and to participate in a National
Community Outreach Program. Lab staff
continued their mentoring activities with
students at  the 4th Street Elementary School
in Athens, our Partner in Education.
[K. McDaniel, 706-546-3524]
Achievement Awards to
Azarraga, Barnwell

Dr. Leo Azarraga and Mr. Thomas Barnwell
received EPA Science Achievement Awards
for 1992. Recipients are selected by a panel
chaired by EPA's Scientific and Technical
Careers Advisory Committee and including
professional society representatives to recog-
nize Agency scientists for outstanding contri-
butions in specific technical  fields. Each
award is established in conjunction with a
professional society.

Dr. Azarraga's award, in the field of chemistry,
is granted "for innovative development and
application of laser spectroscopy and the
Competitive Equilibrium Gaussian Distribu-
tion Model to the quantitative understanding
of toxic metal speciation in environmental and
biological systems."

Mr. Barnwcll's award, in the field of water
quality, is provided "for insightful leadership
in applying state-of-the-art modeling and
computing concepts to meet high priority
Agency water quality modeling needs."
Lab Papers Win Sci-Tech Awards

A journal article by Dr. Craig Barber, Dr. Luis
Suarez, and Dr. Ray Lassiter claimed top
honors in this year's presentation of the EPA
Office of Research and Development's
Scientific and Technological Achievement
Awards. The Level I award, one of only two
presented, went to "Modelling
Bioaccumulation of Organic Pollutants in Fish
with an Application to PCBs in Lake Ontario
Salmonids."
EPA's Science Advisory Board also awarded
Level III honors to two Lab articles. The
articles were "Ester Hydrolysis Rate Constants
Prediction from Infrared Interferograms" by
Dr. Timothy Collette and "Regiospecific
Dechlorination of Pentachlorophenol by
Dichlorophenol-Adapted Microorganisms in
Freshwater, Anaerobic Sediment Slurries" by
Dr. John Rogers (EPA coauthor).

In the overall process for recognizing outstand-
ing research by EPA employees, the Science
Advisory Board granted 29 awards from the 114
scientific articles nominated by 16 EPA Labs
and Offices.
Rogers  Heads Bioremediation
Committee

Dr. John Rogers was named Chair of the
Scientific Steering Committee (Matrix Man-
ager) for the Office of Research and
Development's Bioremediation Research
Program. The committee recommends
resource allocations and directs the
bioremediation programs that support
Supcrfund and hazardous waste cleanup
activities.
McCutcheon Named Journal
Editor

The American Society of Civil Engineers
selected Dr. Steve McCutcheon for a 2-year
voluntary appointment as editor of the Journal
of Environmental Engineering. In this honorary
position, he will provide editorials and editor's
notes bearing on the needs of the environmen-
tal engineering profession.

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 Russo Serves on NAS Committee

 Dr. Rosemarie Russo serves on the National
 Academy of Science's Advisory Committee on
 Russia and the Newly Independent States.
 The Committee provides advice to the
 leadership of the Academy on scientific and
 technological issues related to the former
 Soviet Union and advises on most appropriate
 activities for the NAS in support of U.S.
 interests.
 Richardson Takes AWWA Post

 Dr. Susan Richardson was appointed to a
 research committee of the American Water
 Works Association.  The committee reviews
 research proposals and provides continuing
 oversight of research in progress.
ACS Recognizes Zepp

The American Chemical Society's Division of
Environmental Chemistry selected Dr.
Richard Zepp to receive its Distinguished
Service Award for 1992. The award recognizes
Dr. Zepp's activities on the Environmental
Chemistry Executive Committee.
Barnwell Named to ASCE
Council

Mr. Thomas Barnwell accepted appointment
to the Executive Committee of the American
Society of Civil Engineers' Technical Council
on Computer Practices.
Russo Given Polish Medal

The Institute of Meteorology and Water
Management in Warsaw, Poland, presented its
Gabriel Narutowicz Medal to Dr. Rosemarie
Russo. The medal was awarded for Distin-
guished Service to Environmental Science and
Engineering.
 Loux on Journal Editorial Board

 The Editorial Board of Science and Technol-
 ogy Letters, Middlesex, United Kingdom,
 selected Dr. Nicholas Loux for a 1-year,
 voluntary, honorary appointment as an Ameri-
 can Editor for Chemical Speciation and
 Bioavailability.
 Burns Named to Risk Assessment
 Forum

 EPA's Risk Assessment Council named Dr.
 Lawrence Burns to its Risk Assessment Forum.
 The 13-member Forum promotes Agency-
 wide consensus on risk assessment issues and
 assures that this consensus is incorporated into
 appropriate risk assessment guidance.
Zepp, Burke Get Innovative
Research Funding

A research proposal by Dr. Richard Zepp and
Dr. Roger Burke was selected for award under
the Office of Research and Development's
Innovative Research Program. The 1-year
project will develop an improved understand-
ing of the role of fire in climate-biosphere
interactions through the examination of
polycyclic aromatic hydrocarbon content in
selected environmental samples that have
served as natural archives of past fire events.
The research will be conducted in collabora-
tion with experts at the U.S. Forest Service
and Duke University.
Lewis Is Sigma Xi Secretary

Dr. David Lewis, Research Microbiologist at
the Athens Lab, was elected Secretary of the
University of Georgia Chapter of Sigma Xi, the
National Scientific Research Society.

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New Soil Scientist

Dr. Dcrmont Bouchard, Research Soil Scien-
tist, joined the Lab staff in August and as-
sumed direction of the Center for Exposure
Assessment Modeling. An EPA employee
since 1985, Dr. Bouchard came to the Lab
from a research liaison assignment between
EPA and the USDA Agricultural Research
Service in Bcltsvillc MD. Prior to that he was
ORD's Regional Scientist at EPA Region 7.
He began his EPA career at the R.S. Kerr
Environmental Research Laboratory-Ada OK.
He has a Doctorate in Agronomy from the
University of Arkansas.
New Analytical Chemist

Ms. Dalizza Colon, who holds a Master's
Degree in Analytical Chemistry from the
University of Puerto Rico, joined the staff in
August. Her current research examines the
binding of atrazinc and its degradation prod-
ucts to natural organic matter.
Science and Management Fellow

Ms. Ida Rosario-Hcbcr, an Environmental
Science and Management Fellow, Class of
1993, under the National Urban Fellow's
Program, joined the staff for a year-long
residency.  As a Special Assistant to the
Laboratory Director, she participates in the
Lab's environmental education program and is
conducting an Environmental Education
Assessment Survey for Educators.
 New NRC Associates

 Two scientists joined the staff under the
 National Research Council Associates Pro-
 gram.  Dr. William Miller's research examines
 photochemical carbon transformation in natural
 systems as part of the Lab's Global Change
 Research Program. Dr. Matthew Tarr is
 performing fundamental studies of photo-
 chemical transformations of pollutants on plant
 surfaces.
DOE Research Visitor

Ms. Louise Criscenti of the Department of
Energy/Battelle Northwest Laboratory joined
the Lab on a year-long Interagency Agree-
ment. She is assessing the use of subsurface
geochemical and reactive solute transport
models in regulatory decision-making at
Superfund and hazardous waste sites, and
testing the applicability of new models in
interpreting field and laboratory data.
International Research Visitors

Eight scientists from six countries visited the
Laboratory for periods of 2 to 12 months to
carry out joint research with staff experts.  The
visitors represented the National Institute for
Public Health and Environmental Protection,
Bilthoven, The Netherlands; the State Key
Laboratory of Environmental Aquatic Chemis-
try, Chinese Academy of Sciences, Beijing,
PRC; Institute of Meteorology and Water
Management, Warsaw, Poland; Central
Pollution Control Board, New Delhi, India;
CIBA-Geigy Corporation, Basel, Switzerland;
and the University of Catalonia, Barcelona,
Spain. The Lab hosted brief (day-long) visits
of scientists from Japan, Germany, The
Netherlands,  Brazil, Venezuela, South Africa,
and the Czech and Slovak Federal Republic.
 Chemist Begins Research in
 Germany

 Dr. Wayne Garrison, Chemistry Branch Chief,
 began an 11-month joint investigation of the
 environmental fate of pollutants at the Insti-
 tute for Ecological Chemistry of the GSF
 Research Center for the Environment and
 Health, Munich, Germany.

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 Ananyeva, N.D., N.N. Naumova, J.E. Rogers, and W.G. Steen. 1992. Microbial Transformation of
        Selected Organic Chemicals in Natural Aquatic Systems.  In: Fate of Pesticides and
        Chemicals in the Environment. Q.L. Schnoor (ed.). New York, John Wiley & Sons, Inc. p.
        275-294.

 Barnwell, T.O., R.B. Jackson, E.T. Elliott, E.A. Paul, K. Paustian, A. Donigian, A. Patwardhan, A.
        Rowell, and K. Weinrich.  1992. An Approach to Assessment of Management Impacts on
        Agricultural Soil Carbon. Water, Air, and Soil Pollution.  64(l/2):423-435.

 Baughman, G.L., E.J. Weber, R.L. Adams, and M.S. Brewer.  1992. Fate of Colored Smoke Dyes.
        U.S. Department of the Army, Fort Detrick MD.

 Burke, R.A., T.R. Barber, and W.M. Sackett.  1992. Seasonal Variations of Stable Hydrogen and
        Carbon Isotope Ratios of Methane in Subtropical Freshwater Sediments. Global Geochemi-
        cal Cycles. 6(2): 125-138.

 Cavanaugh, J.E., H.S. Weinberg, A. Gold, R. Sangalah, W. Marbury, W. Glaze, T.W. Collette, S.D.
        Richardson, and A.D.  Thruston,  Jr.  1992.  Ozonation Byproducts:  Identification of
        Bromohydrins from the Ozonation of Natural  Waters with Enhanced Bromide  Levels.
        Environmental Science and Technology. 11(7):981-991.
 Cubillo, F., B. Rodriguez, andT.O. Barnwell. 1992.  A System for Control of River Water Quality of
        the Community of Madrid Using QUAL2E. Water Science and Technology. 26(7-8):1867-
        1873.

 Donaldson, W.T. 1992. The Role of Property-Reactivity Relationships in Meeting EPA's Needs for
        Environmental Fate Constants. Environmental Toxicology and Chemistry. 11(7):887-891.
 Donigian, A.S. and L.A. Mulkey.  1992.   STREAM: an Exposure Assessment Methodology for
        Agricultural Pesticide Runoff. In: Fate ofPesticides and Chemicals in the Environment. J.L.
        Schnoor (ed.). New York, John Wiley & Sons. p. 297-330.

 Haggblom, M.M., J. Kazumi, M.D. Rivera, L.Y. Young, and J.E. Rogers.  1992. Anaerobic Transfor-
        mation and Degradation of Chlorobenzoates and Chlorophenols Under Four Reducing
        Conditions. In: Bioremediation of Hazardous Wastes (Abstracts from 5th Symposium on U.S.
        EPA's Biosystems Technology Development Program). U.S. Environmental Protection
        Agency, Washington DC. Publication No. EPA/600/R-92/126. p. 107-108.
 Hamrick, K.J., H.P. Kollig, and B.A. Bartell.  1992. Computerized Extrapolation of Hydrolysis Rate
        Data. Journal of Chemical Information and Computer Sciences.  32(5):511-514.
 Hicks, D.B., J.B. McConnell, L.E. Asmussen, R.A. Leonard, and C.N. Smith. 1992. Movement and
        Fate of Agricultural Chemicals in the Surface and Subsurface Environments  Near Plains,
        Southwestern Georgia—Integrated Network Plan. U.S. Geological Survey, Doraville GA.
 Hou, M. and G.L. Baughman.  1992. Predicting the Precipitation of Acid and Direct Dyes in Natural
        Waters. Dyes and Pigments. 18(l):35-46.

Jackson, R.B. 1992. On Estimating Agriculture's Net Contribution to Atmospheric Carbon.  Water,
       Air, and Soil Pollution.  64(1/2):121-137.
Jensen, P. I. Aagaard, R.A. Burke, P.R. Dando, N.O. Jorgensen, A. Kuijpers, T. Laier, S.C.M. O'Hara,
       and R. Schmaljohann. 1992. "Bubbling Reefs" in the  Kattegat: Submarine Landscapes of
       Carbonate-Cemented Rocks  Support a Diverse Ecosystem at Methane Seeps.  Marine
        Ecology Progress Series. 83(7):103-112.

Jones, W.J. and I.C. Kong. 1992. Effects of Metals on the Reductive Dechlorination of Chlorophenols.
       In:  Bioremediation of Hazardous Wastes (Abstracts of 5th  Symposium on U.S. EPA's
       Biosystems Technology Development Program).  U.S. Environmental Protection Agency,
       Washington DC. Publication No. EPA/600/R-92/126. p. 55-56.

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Lckcvicius, B., D. Sabaliunas, A. Knabikas, and J. Jankauskas. 1992.  Ames Mutagenicity Tests of
       Three Acetanilide Herbicides During Their Alkaline Degradation. International Journal of
       Analytical Chemistry. 46(1-3): 141-147.
Lewis, D.L., A.P. Simons, W.B. Moore, and D.K. Gattic. 1992. Treating Soil Solution Samplers to
       Prevent Microbial Removal of Analytes. Applied Environmental  Microbiology. 58(l):l-5.

Mullen, M.D., D.G. Wolf, T.J. Bcveridge, and G.W. Bailey. 1992. Sorption of Heavy Metals by the
       Soil Fungi Aspcrgillus niger and Mucorrouxii. Soil Biology and Biochemistry. 24(2):129-135.

Parrish, R.S., C.N. Smith, and F.K. Fong.  1992. Tests of the Pesticide Root Zone Model and the
       Aggregate Model for Transport and Transformation of Aldicarb, Metolachlor, and Bromide.
       Journal of Environmental Quality. 21(4):685-697.
Pcijncnbcrg, W.G.J.M., M.J. t'Hart, H.A. den Hollander, D. van de Meent, H. H. Verbloom, and N.L.
       Wolfe.   1992.   Reductive Transformations of Halogenated Aromatic Hydrocarbons in
       Anaerobic Sediment-Water Systems: Kinetics, Mechanisms, and Products. Environmental
       Toxicology and  Chemistry.  11(3):289-300.
Pcijncnbcrg, W.G.J.M., M.J. t'Hart, H.A. den Hollander, D. van de Meent, H.H. Verbloom, and N.L.
       Wolfe.  1992. QSARs for Predicting Reductive Transformation Rate Constants of Haloge-
       nated Aromatic Hydrocarbons in Anoxic Sediment Systems. Environmental Toxicology and
       Chemistry. 11(3):301-314.
Plis, Y.I.  1992.  An Approach to Calculating Wind-Driven Currents and Transport of Substances in
        Unstratified  Water Bodies Using  Curvilinear Coordinates.   Water Resources Research.
        28(l):83-88.    .
Richardson, S.D.,  J.M.  McGuire, A.D. Thruston, Jr., and G.L. Baughman.   1992. Structural
        Characterization of Sulfonated Azo Dyes Using Liquid Secondary Ion Mass Spectrometry/
        Tandem Mass Spectrometry. Organic Mass Spectrometry. 27(3):289-299.

Risscr, J. A. and G.W. Bailey. 1992. Spcctroscopic Study of Surface Redox Reactions with Manganese
        Oxides. Soil Science Society of America Jouranl 56(l):82-88.

Rogers, J.E., W.J. Jones, E.J. Weber, and R.L.  Adams.  1992.  Proposed PCB Biodegradation Study
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   •tr U.S. Government Printing Office: 1993 - 750-002 (60196)

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