United States United States
 Environmental Protection


Agency Geological Survey


Proceedings and


Summary Report


Workshop on the Fate, 

Transport, and 

Transformation of Mercury in 

Aquatic and Terrestrial 

Environments 
Everglades cover photo courtesy of C. Gilmour, The Academy of Natural Sciences Estuarine Research Center. 
EPA/625/R-02/005 

June 2002 

Proceedings and Summary Report

Workshop on the Fate, Transport, 

and Transformation of Mercury in 

Aquatic and Terrestrial Environments

May 8 – 10, 2001 

West Palm Beach, Florida 

National Risk Management Research Laboratory

Office of Research and Development

U.S. Environmental Protection Agency

Cincinnati, Ohio 45268

Toxic Substances Hydrology Program

Office of Water Quality

United States Geological Survey

Reston, VA 20192
NOTICE 

This document was compiled from presentations and open discussion at a U.S. Environmental 

Protection Agency (USEPA) Workshop on the Fate, Transport, and Transformation of Mercury in 

Aquatic and Terrestrial Environments held in West Palm Beach, Florida. The agenda and 

speaker/poster abstracts are presented in the appendices. Information presented herein does not 

necessarily represent the views of USEPA, nor is it specifically tied to reference materials. In many 

cases, the information presented is the opinion of the speaker, generated by his or her background 

and operations experience. 

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FOREWORD 

The U.S. Environmental Protection Agency is charged by Congress with protecting the 

Nation‘s land, air, and water resources. Under a mandate of national environmental laws, the 

Agency strives to formulate and implement actions leading to a compatible balance between human 

activities and the ability of natural systems to support and nurture life. To meet this mandate, EPA‘s 

research program is providing data and technical support for solving environmental problems today 

and building a science knowledge base necessary to manage our ecological resources wisely, 

understand how pollutants affect our health, and prevent or reduce environmental risks in the future. 

The National Risk Management Research Laboratory is the Agency‘s center for investigation 

of technological and management approaches for preventing and reducing risks from pollution that 

threaten human health and the environment. The focus of the Laboratory‘s research program is on 

methods, and their cost-effectiveness, for prevention and control of pollution to air, land, water, and 

subsurface resources; protection of water quality in public water systems; remediation of 

contaminated sites, sediments and ground water; prevention and control of indoor air pollution; and 

restoration of ecosystems. NRMRL collaborates with both public and private sector partners to 

foster technologies that reduce the cost of compliance and to anticipate emerging problems. 

NRMRL‘s research provides solutions to environmental problems by developing and promoting 

technologies that protect and improve the environment; advancing scientific and engineering 

information to support regulatory and policy decisions; and providing the technical support and 

information transfer to ensure implementation of environmental regulations and strategies at the 

national, state, and community levels. 

This publication has been produced as part of the Laboratory‘s strategic long-term research 

plan. It is published and made available by EPA‘s Office of Research and Development to assist the 

user community and to link researchers with their clients. 

E. Timothy Oppelt, Director

National Risk Management Research Laboratory

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TABLE OF CONTENTS

Section Page Number 

NOTICE ii 

FOREWORD iii 

TABLE OF CONTENTS v 

ACRONYMS ix 

ACKNOWLEDGMENTS xi 

SECTION 1 INTRODUCTION 1 

SECTION 2 SCOPE AND OBJECTIVE OF THE WORKSHOP 3 

SECTION 3 SUMMARY OF THE PLENARY SESSION 5 

3.1 Plenary Session 5 

3.1.1 USEPA‘s Mercury Research Strategy – Douglas W. Grosse, USEPA, 

National Risk Management Research Laboratory (NRMRL) 5 

3.1.2 USGS/USEPA Mercury Roundtable: Enhancing Interagency 

Collaborations – Sarah Gerould, USGS 6 

3.1.3 State of Florida/Mercury Science Program – Tom Atkeson, Florida 

Department of Environmental Protection (DEP) 7 

3.1.4 USEPA STAR Program – Bill Stelz, USEPA, National Center For 

Environmental Research (NCER) 8 

3.1.5 Electric Power Research Institute – Leonard Levin, EPRI 8 

3.1.6 National Wildlife Federation (NWF) Great Lakes Natural Resource 

Center – Mike Murray, NWF 10 

3.2 Keynote Speakers 11 

3.2.1 Atmospheric Deposition Overview – Gerald Keeler, University of 

Michigan 11 

3.2.2 Historic Perspectives on Mercury – Don Porcella, Environmental 

Science & Management 14 

SECTION 4 SUMMARY OF THE TECHNICAL SESSIONS 17 

4.1 Session A: Mercury and Methylmercury Transport in the Environment 

17 

4.1.1 Determination of the Sediment-Water Exchange of Mercury and 

Methylmercury: Approaches, Limitations, Observations – G. Gill, 

Texas A&M University 17 

4.1.2 Mercury and Methylmercury Accumulation in Lake Sediment: What 

Can We Infer from Dated Cores? – D. Engstrom, Science Museum of 

Minnesota 17 

4.1.3 An Overview of Mercury Cycling in the Boreal Ecosystem – V. St. 

Louis, University of Alberta 18 

4.1.4 Is the Arctic a Missing Sink for Mercury? New Measurements of 

Depletion Events, Deposition and Speciation in Air and Snow at Point 

Barrow, Alaska – Steven E. Lindberg, Oak Ridge National Laboratory 19 

4.1.5 Putting into Perspective Mercury Emissions from Geologic Sources – 

M. Sexauer Gustin, University of Nevada-Reno 19 

4.1.6 Mercury Cycling in the Boreal Forest: Insights from Models, 

Experiments, and Isotopes – B. Branfireun, University of Toronto at 

Mississauga 20 

4.2 Session B: Bioaccumulation of Mercury in Aquatic Food Webs 21 

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Section Page Number 

4.2.1 Evolution of a Contaminant Problem: Mercury in Freshwater Fish – J. 

Wiener, University of Wisconsin-La Crosse 21 

4.2.2 Projecting the Population-Level Effects of Mercury on the Common 

Loon in the Northeast – D. Evers, BioDiversity Research Institute 22 

4.2.3 USGS National Pilot Study of Contamination of Aquatic Ecosystems 

Along Multiple Gradients: Bioaccumulation in Fish – W. Brumbaugh, 

National Pilot Study of Mercury 22 

4.2.4 Interactions of Trophic Position and Habitat with Mercury 

Bioaccumulation in Florida Everglades Largemouth Bass (Micropterus 

salmoides) – T. Lange, Florida Fish and Wildlife Conservation 

Commission 23 

4.2.5 Bioaccumulation of Mercury in the Everglades: Patterns in the 

Foodweb – J. Trexler, Florida International University 24 

4.2.6 Effects of Rainbow Smelt Invasion on Mercury Concentrations of 

Predatory Fish of Northwestern Ontario and Manitoba, Canada – R. 

Bodaly, Department of Fisheries and Oceans, Freshwater Institute, 

Canada 24 

4.3 Session C: STAR Program Review 25 

4.3.1 Formation/Transport of Methylmercury in Ecosystems and Watersheds 25 

4.3.1.1 Watershed Influences on the Transport, Fate, and Bioavailability of 

Mercury in Lake Superior – J. Hurley, University of Wisconsin 25 

4.3.1.2 Factors Controlling Methylmercury Production in Sediments and Fate 

in Aquatic Systems – R. Mason, University of Maryland 26 

4.3.1.3 Response of Methylmercury Production and Accumulation to Changes 

in Mercury Loading: A Whole-Ecosystem Mercury Loading Study – 

C. Gilmour, The Academy of Natural Sciences, Estuarine Research 

Center 26 

4.3.1.4 Methylmercury Sources to Lakes in Forested Watersheds: Has 

Enhanced Methylation Increased Mercury in Fish Relative to 

Atmospheric Deposition? – J. Jeremiason, Minnesota Pollution 

Control Agency 27 

4.3.2 Biogeochemical Controls on Mercury Methylation/Demethylation 

Rates 29 

4.3.2.1 Photochemistry of Mercury in Saginaw Bay Watershed, Michigan: 

Annual USEPA STAR Project Meeting – J. Nriagu, University of 

Michigan 29 

4.3.2.2 Chemical and Biological Control of Mercury Cycling in Upland, 

Wetland and Lake Ecosystems in the Northeastern United States – C. 

Driscoll, Syracuse University 29 

4.3.3 Physical and Chemical Processes Affecting Mercury Cycling 30 

4.3.3.1 Processes Controlling the Chemical/Isotopic Speciation and 

Distribution of Mercury from Contaminated Mine Sites – G. Brown, 

Stanford University 30 

4.3.3.2 Microbiological and Physiochemical Aspects of Mercury Cycling in 

the Coastal/Estuarine Waters of Long Island Sound and Its RiverSeawater Mixing Zones – W. Fitzgerald, University of Connecticut 31 

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Section Page Number 

4.3.3.3 Redox Transformation of Mercury – F. Morel, Princeton University 32 

4.3.3.4 Assessing the Role of Plants in the Biogeochemical Cycle of Mercury 

– M. Gustin, University of Nevada 32 

4.3.3.5 Mercury and Methylmercury Burdens in Sediments, Water, and Biota 

of VT and NH Lakes, and Trends in Paleolimnology-Inferred Mercury 

Deposition to VT and NH – N. Kamman, VT Department of 

Environmental Conservation 33 

4.3.3.6 Mercury in Fish and Sediments of Clear Lake, California: Defining the 

Problem and Developing Cleanup Options through the USEPA 

Superfund Program – E. Mange 33 

4.4 Session D: Managing Mercury Contamination in Aquatic/Terrestrial 

Systems 35 

4.4.1 An Assessment of the Ecological and Human Health Impacts of 

Mercury in the Bay-Delta Watershed: A CALFED Study – C. Foe, 

Central Valley Regional Water Quality Control Board 35 

4.4.2 An Evaluation of USEPA's Bioaccumulation Factor for Mercury: A 

Regulated Industry Perspective – R. Reash, American Electric Power 36 

4.4.3 Methylmercury in Terrestrial Ecosystems: Summary of Swedish 

Research – J. Munthe, IVL Swedish Environmental Research Institute 36 

4.4.4 Interfacing Process-Level Research and Ecosystem-Level Management 

Questions: Aquatic Cycling of Mercury in the Everglades Phase II – 

D. Krabbenhoft, U.S. Geological Survey 36 

4.4.5 Modeling Mercury Fate in Seven Georgia Watersheds – R. Ambrose, 

Jr., USEPA 37 

4.4.6 Fitting into the North American Mercury Emissions Reduction Priority 

– L. Trip, Environment Canada 38 

4.5 Session E: Methylmercury Production in the Environment 

39 

4.5.1 Overview of Microbial Methylmercury Production and Degradation: 

What Do We Know? What Don't We Know? – C. Gilmour, The 

Academy of Natural Sciences 39 

4.5.2 Environmental Controls on Methylmercury Production and 

Degradation in Florida Everglades Sediment – M. MarvinDiPasquale, U.S. Geological Survey 39 

4.5.3 Group VI Anions and Mercury Transformation within the S-cycle in 

the Carson River System, Nevada – J.C. Bonzongo, University of 

Florida 40 

4.5.4 A Bacterial Biosensor for Aquatic Hg(II) Speciation and 

Bioavailability – P. Barrocas, Florida State University 40 

4.5.5 Facilitated Uptake of Mercury at Trace Concentrations by Escherichia 

coli and Vibrio anguillarum – G. Golding, University of Manitoba 

41 

4.5.6 Mercury Transport and Transformation in the Wider Idrija Region and 

the Gulf of Trieste – M. Horvat, Institute Jozef Stefan 42 

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Section Page Number 

4.5.7 The Everglades Mercury Cycling Model: Development and 

Application to Two Marsh Sites in the Florida Everglades – R. Harris, 

Tetra Tech, Inc. 42 

4.6 Combined Session 43 

4.6.1 Landscape Patterns of Mercury Contamination Across the Everglades 

Ecosystem – J. Stober, USEPA Region 4 and K. Thornton, FTN 

Associates Ltd. 43 

4.6.2 Use of Path Analysis to Integrate the Effects of Multiple Stressors on 

Mercury Contamination in the Everglades Ecosystem – K. Thornton, 

FTN Associates Ltd. and J. Stober, USEPA Region 4 44 

4.6.3 METAALICUS: A Study to Determine the Relationship Between 

Mercury Deposition and Methylmercury Concentrations of Fish – J. 

Rudd, Department of Fisheries and Oceans Canada and R. Harris, 

Tetra Tech Inc. 44 

SECTION 5 SUMMARY OF THE PANEL DISCUSSIONS 47 

5.1 Mercury And Methylmercury Transport in The Environment – D. 

Krabbenhoft 47 

5.1.1 What We Know 47 

5.1.2 What We Don‘t Know 48 

5.1.3 Open Discussion 49 

5.2 Methylmercury Production in The Environment – C. Gilmour 

50 

5.2.1 What We Know 50 

5.2.2 What We Don‘t Know 50 

5.2.3 Open Discussion 50 

5.3 STAR Program Review – J. Hurley 52 

5.3.1 What We Know 52 

5.3.2 What We Don‘t Know 52 

5.3.3 Open Discussion 53 

5.4 Management of Mercury Contamination in Aquatic/Terrestrial Systems 

– Luke Trip 53 

5.4.1 What We Know 53 

5.4.2 What We Think We Know 53 

5.4.3 What We Don‘t Know 54 

5.4.4 Open Discussion 54 

5.5 Bioaccumulation of Mercury in Aquatic Food Webs – Jim Wiener 

55 

5.5.1 What We Know 55 

5.5.2 What We Don‘t Know 56 

5.5.3 Open Discussion 57 

FIELD TRIP TO THE EVERGLADES 57 

APPENDIX A WORKSHOP AGENDA A-1 

APPENDIX B SPEAKER ABSTRACTS B-1 

APPENDIX C POSTER ABSTRACTS C-1 

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ACRONYMS 

ACME Aquatic Cycling of Mercury in the Everglades

AMD Acid Mine Drainage 

ATSDR Agency for Toxic Substances and Disease Registry 

AVS Acid-volatile sulfide

BAF Bioaccumulation Factor

CEC Commission for Environmental Cooperation

CEM Continuous Emissions Monitoring

CRS Carson River System

CV-AFS Cold-Vapor Atomic Fluorescence Spectrometry 

CWA Clean Water Act

DGM Dissolved Gaseous Mercury

DEP Department of Environmental Protection

D-MCM Dynamic Mercury Cycling Model

DOC Dissolved Organic Carbon

E-MCM Everglades Mercury Cycling Model

Eh Redox potential

EMAP Environmental Monitoring and Assessment Program

ELA Experimental Lakes Area

ENRP Everglades Nutrient Removal Project

USEPA United States Environmental Protection Agency

EPG Electric Power Generation 

EPRI Electric Power Research Institute

FDA Food and Drug Administration

GEM Gaseous Elemental Mercury 

GIS Geographic Information System

ICP Inductively Coupled Plasma

LFG Landfill Gas 

LIF Laser Induced Fluorescence 

LIS Long Island Sound

MARB Mobile-Alabama River Basin 

MAWLTS Mercury in Adirondack Wetlands Lakes and Terrestrial Systems

MCL Maximum Contaminant Level 

MDE Mercury Depletion Events

MDN Mercury Deposition Network 

MeHg Methylmercury (monomethylmercury)

METAALICUS Mercury Experiment To Assess Atmospheric Loading In Canada and the

United States 

NADP National Atmospheric Deposition Program 

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NARAP North American Regional Action Plan

NAWQA National Water Quality Assessment

NCER National Center For Environmental Research

NRMRL National Risk Management Research Laboratory

NWF National Wildlife Federation

OC Organic Carbon 

ORD Office of Research and Development (USEPA)

ORNL Oak Ridge National Laboratory 

PBT Persistent, bioaccumulative and toxic [chemicals]

POC Particulate Organic Carbon 

RARE Regional Applied Research Effort 

RELMAP Regional Lagrangian Model of Air Pollution

RGM Reactive Gaseous Mercury

SBMM Sulphur Bank Mercury Mine 

SFWMD South Florida Water Management District

SoFAMMS South Florida Atmospheric Mercury Monitoring Study

SRB Sulfate-Reducing Bacteria 

STA Stormwater Treatment Area

STAR Science to Achieve Results [Program]

SUVA Specific Ultra-Violet Absorbance 

THg Total Mercury

TMDL Total Maximum Daily Load

TOC Total Organic Carbon

TP Total Particulates

TRV Toxicity Reference Value

USGS United States Geological Survey

WASP5 Water Quality Analysis Simulation Program

WCA Water Conservation Area (Everglades)

WCS Watershed Characterization System

WTF Waste Treatment Facility

XAFS X-Ray Absorption Fine Structure

XRD X-Ray Diffraction

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ACKNOWLEDGMENTS 

Several people contributed to developing and conducting this workshop. The Organizing 

Committee, chaired by Scott Minamyer of the USEPA‘s National Risk Management Research 

Laboratory, included the following individuals: 

Rochelle Araujo USEPA ORD National Exposure Research Laboratory-Athens 

Thomas Atkeson Florida Department of Environmental Protection and the South 

Florida Mercury Science Program 

Marilyn Engle USEPA Office of International Affairs 

David Krabbenhoft USGS, Water Resources Division, Toxics Program 

Arnie Kuzmack USEPA Office of Water, Office of Science and Technology 

Leonard Levin Electric Power Research Institute 

Michael Murray National Wildlife Federation 

Paul Randall USEPA ORD National Risk Management Research Laboratory 

William Stelz USEPA ORD National Center for Environmental Research, 

Quality Assurance and the STAR Program 

Jerry Stober USEPA Region 4, Science and Ecosystem Support Division 

Lisa Kulujian, Alina Martin, Evelyn Hartzell, Lisa Mahoney, and Marc Fuentebella of the 

Science Applications International Corporation (SAIC) provided workshop logistical support. 

David Krabbenhoft and Scott Minamyer provided technical guidance for this report which was 

prepared by Evelyn Hartzell of SAIC. 

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