United States

Environmental Protection

Agency

Office of Air Quality

Planning and Standards

Research Triangle Park, NC 27711

EPA-453/R-00-005

June 2000

Deposition of Air Pollutants

to the Great Waters

Third Report to Congress
Cover photo credits:

S.C. Delaney/EPA S.C. Delaney/EPA

S.C. Delaney/EPA

S.C. Delaney/EPA

S.C.

Delaney/EPA

Carole Y. Swinehart/

Michigan Sea Grant

Extension

ACKNOWLEDGMENTS

The report was prepared by the Office of Air Quality Planning and Standards of the U. S.

Environmental Protection Agency (EPA). The Project Leads were Gail Lacy and Dale Evarts. Completion

of this report could not have been possible without significant contributions from the wider community of

scientists and environmental experts involved with the programs and issues described in the report. In

particular, EPA would like to thank those persons who provided peer review of the draft report:

Mary Ann Allan Electric Power Research Institute, Palo Alto, California

Dr. Caroline Currin National Marine Fisheries Service, Beaufort, North Carolina

Elisabeth Galarneau Atmospheric Environment Service, Ontario, Canada

Dr. Louis Guillette Department of Zoology, University of Florida

Dr. Michael Murray National Wildlife Federation, Ann Arbor, Michigan

Dr. Hans Paerl Institute of Marine Sciences, University of North Carolina

Dr. Joseph Scudlark College of Marine Sciences, University of Delaware

In addition, EPA would like to acknowledge the substantive review and contributions provided by

Richard Artz and Margaret Kerchner of the Air Resources Lab of the National Oceanographic and

Atmospheric Administration, by Bob Larson of the National Atmospheric Deposition Program, and by

many staff of State, local and tribal agencies.

Within EPA, we would like to acknowledge the contributions of the Agency work group members

and others involved in the development of the report, including staff (too numerous to name) in the Offices

Air and Radiation, Water, Research and Development, Solid Waste and Emergency Response, Prevention,

Pesticides, and Toxic Substances, and General Counsel, as well as in the Great Lakes National Program

Office, the Chesapeake Bay Program Office, the Gulf of Mexico Program Office, EPA Regions IV and V,

and the National Estuary Program.
Deposition of Air Pollutants to the Great Waters – 3rd Report to Congress 2000 Page i

Great Waters Pollutants of Concern

Cadmium and cadmium compounds

Chlordane

DDT/DDE

Dieldrin

Hexachlorobenzene

"-Hexachlorocyclohexane

Lindane ((-hexachlorocyclohexane)

Lead and lead compounds

Mercury and mercury compounds

Polychlorinated biphenyls 

Polycyclic organic matter 

Tetrachlorodibenzo-p-dioxin (dioxins)

Tetrachlorodibenzofuran (furans)

Toxaphene

Nitrogen compounds

EXECUTIVE SUMMARY

With section 112(m) of the 1990 Clean Air Act (CAA), Congress directed the U.S.

Environmental Protection Agency (EPA), in cooperation with the National Oceanic and Atmospheric

Administration (NOAA), to identify and assess the extent of atmospheric deposition of air pollutants to

the Great Lakes, the Chesapeake Bay, Lake Champlain, and coastal waters, collectively known as the

Great Waters. Further, section 112(m) directed EPA to report its findings to Congress in periodic

reports. This is EPA’s third Report to Congress on the deposition of air pollutants to the Great Waters. 

The first report was published in May 1994, and the second report was published in June 1997.

The goals of the Third Great Waters Report to Congress are to discuss the current state of

knowledge regarding atmospheric deposition of pollutants to the Great Waters based on new research

and program activities undertaken since the Second Report to Congress and to describe any necessary

revisions to requirements, standards, and limitations under the CAA or other Federal laws. This report is

not intended to be a comprehensive summary of all relevant scientific research and activities. Instead, it

summarizes and highlights major trends and key findings, and builds on conclusions presented in the

First and Second Reports to Congress.

How does deposition of air pollutants affect public health and the

health of the Great Waters ecosystems?

A rapidly growing number of atmospheric

deposition monitoring and modeling studies confirm

that, along with runoff and discharges of pollution into

waterways, atmospheric deposition is a significant

pathway of pollutant inputs to the Great Waters. These

studies show that the contribution of atmospheric

deposition to overall pollutant loadings varies greatly by

pollutant and location. For example, studies show that

atmospheric deposition contributes from less than 5 to

100 percent of dioxins and furans entering the Great

Lakes, depending on the location of the monitoring site,

and from 2 to 38 percent of the nitrogen load to certain

coastal waters. Given this variability in contributions,

the improvement of the quality of the Great Waters

environments requires an understanding of all of the

sources of the pollutants into a waterbody, including

runoff from urban areas and farms, discharge from point sources, and seepage from contaminated

sediments, as well as atmospheric deposition.

Like the First and Second Reports to Congress, this report focuses on 15 pollutants of concern,

including certain pesticides, metal compounds, chlorinated organic compounds, and nitrogen compounds

(see sidebar). Some of these pollutants are single compounds while others represent categories of several

or even hundreds of individual compounds. They are emitted into the air by a wide range of sources,

including industries and other human activities, natural sources, and re-emissions of these pollutants from

soil and water. What is known about their emission rates, concentrations in the environment,

transformation processes, deposition rates and pathways, and health and environmental effects varies

widely. Nevertheless, recent research has added to our knowledge of the adverse human health and

ecological effects of these pollutants. At certain levels, these pollutants are associated with adverse
Executive Summary

Page ii Deposition of Air Pollutants to the Great Waters – 3rd Report to Congress 2000

effects on many target organs in humans and animals, including the liver, kidney, nervous system,

endocrine system, reproductive organs, and immunological system. Research since the Second Report to

Congress provides additional evidence that some of the pollutants are likely “endocrine disruptors,”

meaning they may interfere with the action of hormones in wildlife and humans.

A number of regional and national assessments and monitoring programs described in this report

suggest that, while environmental conditions are improving in general, the current concentrations of

pollutants of concern continue to impair the ecological health of many Great Waters. For example, the

NOAA Estuarine Eutrophication Surveys indicate that approximately 89 percent of the Great Waters that

are coastal estuaries show some degree of adverse effects associated with amounts of nitrogen in excess

of natural levels. (Nitrogen is a natural component of these waterbodies, but excess amounts can also be

introduced through natural and human activities such as runoff from urban and agricultural areas and

atmospheric deposition.) Because of long-range atmospheric transport and certain chemical properties

(e.g., persistence, mobility, bioaccumulation, and bioconcentration), the pollutants of concern may

contribute to ecological impairment far from known emission sources and long after releases.

At current levels of contamination, pollutants of concern in the Great Waters pose potentially the

greatest health risks to individuals who consume fish from contaminated waters for subsistence or

cultural reasons, women of child-bearing age, the developing fetuses of pregnant women, and young

children who consume fish from contaminated waters. For mercury in particular, exposures do not

appear to pose a health risk to people consuming average amounts of fish, but sensitive sub-populations

(e.g., young children, and pregnant women and their developing fetuses) with higher than typical fish

consumption may be at risk. Also at risk are subsistence fish-eating populations who consume large

amounts of fish. The extent of risk for these groups depends on the amount of fish consumed and the

mercury concentrations present in the fish. 

What are the recent and anticipated trends in emission and

deposition of Great Waters pollutants of concern and their

concentrations in the Great Waters environment?

Where monitoring trends information exists, either nationally or locally, atmospheric deposition

of pollutants of concern to the Great Waters has declined or remained relatively constant in recent years,

as described in Chapter II. Specifically, deposition of lead, cadmium, polycyclic organic matter (POM) –

which includes a group of compounds known as polycyclic aromatic hydrocarbons (PAHs) –

polychlorinated biphenyls (PCBs), and some banned or restricted use pesticides is declining in the Great

Lakes. Other Great Waters have also shown decreasing trends of some of the pollutants of concern, such

as lead in Long Island Sound. Deposition of nitrogen in the U.S. has remained fairly constant. These

trends may reflect the results of emission reduction programs established under the CAA, pesticide bans,

as well as other local, tribal, State, Federal, and international pollution control efforts, many of which are

described in this report. There is considerable uncertainty in the trends estimates, however, because

limited monitoring capability, technological barriers, and variable collection and analysis methods make

it difficult to adequately characterize historical or current conditions. In addition, these estimates do not

address all Great Waters waterbodies for all pollutants of concern.

Emissions of mercury to the atmosphere come from human-made sources, natural emissions, and

re-emission from biologic and geologic processes. Emissions of mercury have been on a downward trend

since 1990, due chiefly to the phase-out of mercury in many products. Nevertheless, monitoring suggests

that atmospheric deposition is a significant contributor of mercury to the Great Waters. At EPA’s current

reference dose for mercury, levels in some lakes and streams remain sufficiently high to pose adverse
Executive Summary

Deposition of Air Pollutants to the Great Waters – 3rd Report to Congress 2000 Page iii

human health and ecological risks and to result in fish consumption advisories for mercury in many Great

Waters.

Lead air emissions, ambient air concentrations, and deposition levels in the Great Lakes region

have also decreased in recent years. Cadmium emissions in the Great Lakes region, on the other hand,

increased in the 1980s and have not shown a trend since then, while cadmium deposition in the Great

Lakes region is believed to have decreased in recent years. In the Chesapeake Bay, trends in atmospheric

deposition of lead and cadmium are difficult to discern with current information, but total inputs of both

lead and cadmium in some eastern parts of the bay have increased in recent years due to the increase in

population and industrial activities. In some areas of the Chesapeake Bay, levels of these metals may be

high enough in sediments to cause adverse ecological effects. 

Air emissions of dioxins, furans, and POM (including PAHs) in the U.S. are from both natural

and human-made combustion and incineration processes. Emissions have declined for dioxins and

furans, while trends for POM are not known. A large degree of variation has been observed in deposition

levels of dioxins and furans over time within and between the Great Lakes. Deposition levels of these

compounds are related to the pattern of industrialization and population density. In many instances, long

term monitoring indicates that concentrations of dioxins and furans in biota in the Great Waters have

declined over time. Analytical results indicated that levels in aquatic species are declining steadily and

in several Great Waters, no dioxin was found in fish samples taken between 1987 and 1994. 

Although CAA programs have had a major impact on nitrogen oxide (NOx) emissions, the

emission reductions have been balanced approximately equally with emission increases attributable to

economic growth, resulting in a relatively flat trend since 1980. Deposition monitoring data suggest that

the deposition rates of inorganic nitrogen (e.g., NOx, ammonia) to many of the Great Waters watersheds

have also been relatively constant for the past two decades, though some increases have been noted

downwind of areas where population or livestock operations are growing. The EPA expects that

additional NOx controls to be implemented under the CAA will slightly outpace emission increases

associated with economic growth, resulting in a net decreasing trend in NOx emissions through 2005. 

Emissions are expected to remain steady at that level until 2010. Research is ongoing into the lesser

known, but apparently important, forms of nitrogen deposition (e.g., dry deposition, organic nitrogen). 

Current and anticipated nitrogen deposition rates are significantly greater than natural rates, and

combined with nitrogen inputs from runoff from farms and cities, have the potential to overwhelm the

capacities of surface waters to assimilate the additional nitrogen.

Manufacture of PCBs in the U.S. no longer occurs; however, releases into the environment

continue to occur because of PCBs in electrical transformers and capacitors that are still in use, releases

from soils and sediments contaminated with PCBs, and releases during some combustion processes. The

number and magnitude of PCB sources in the U.S. has decreased 20-fold in the past 20 years. 

Furthermore, deposition of PCBs in the Great Lakes has decreased and a net loss of PCBs has been

observed in the Chesapeake Bay. Overall, PCB concentrations in the environment appear to have

declined but are still present and continue to result in the need for fish consumption advisories in many

Great Waters.

Based on recent academic research on atmospheric pollutant concentrations in the Great Lakes

region, DDT and DDE, followed by dieldrin and chlordane, are estimated to fall below current detection

limits in the atmosphere between 2010 and 2020. Hexachlorocyclohexane and hexachlorobenzene are

projected to be eliminated in the atmosphere by 2030 and 2060, respectively. These estimates assume

current rates of long-range transport of these pollutants into the region and do not mean that

concentrations would be eliminated in deposited media (water and sediments) by these dates. However,
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Page iv Deposition of Air Pollutants to the Great Waters – 3rd Report to Congress 2000

these estimates indicate that reduction strategies in the Great Lakes, along with the original bans and

restrictions on the use of these substances, are having the intended effect.

What actions are EPA and others taking to address atmospheric

deposition?

Chapter III of this report describes more than 60 programs under way from the local to

international levels that directly or indirectly contribute to reducing atmospheric deposition of pollution

to the Great Waters or to understanding its effects. Although EPA leads or supports many of these

programs, which often use multimedia and cross-program approaches to control pollution, other Federal

agencies, State and tribal organizations, industry groups, and Canada have also initiated and implemented

many important activities. Examples of EPA’s cross-program and multimedia approaches include the

pulp and paper industry “cluster rule” that for the first time integrates, coordinates, and streamlines

applicable requirements of the Clean Water Act and the CAA. The EPA’s air and water programs are

also working together to address the contribution of air deposition into water quality protection under

total maximum daily load (TMDL) determinations. This also includes coordinated activities such as the

Persistent Bioaccumulative Toxics Initiative, Clean Water Action Plan, and Contaminated Sediment

Management Strategy. Several State organizations have successfully worked with industry and

municipalities to develop pollution prevention programs and programs to collect banned and restricted

use pesticides. Tribes are working to reduce exposure of indigenous populations to pollutants of concern

through a variety of efforts, and industry has initiated efforts to reduce the use of pollutants of concern in

products and processes. Canada has implemented a variety of programs, some of which are joint efforts

with the U.S., like the Binational Toxics Strategy which seeks to eliminate pollutants of concern from the

Great Lakes environment. 

These coordinated Agencywide efforts demonstrate EPA’s commitment to implement the

strategic directions discussed in the First and Second Reports to Congress and in the section 112(m)(6)

adequacy determination, and to pursue all authorities available for addressing atmospheric deposition and

Great Waters pollutants of concern. In addition, developing and implementing these and other programs

and initiatives described in this report have not required revisions to requirements, standards, and

limitations in accordance with the CAA and other Federal laws which provide protection of human health

and the environment from atmospheric deposition to the Great Waters.

What are EPA’s findings and conclusions from this Third Report

to Congress?

The new scientific and programmatic information presented in this report supports and builds on

the three broad conclusions presented in the First and Second Reports to Congress.

• Atmospheric deposition from human activities can be a significant contributor of toxic chemicals

and nitrogen compounds to the Great Waters. The relative importance of atmospheric loading

for a particular chemical in a given waterbody depends on many factors, including characteristics

of the waterbody, properties of the chemical, and the kind and amount of atmospheric or water

discharges. 

C A plausible link exists between emissions into the air of Great Waters toxic pollutants of

concern, the atmospheric deposition of these pollutants (and their transformation products), and

the concentrations of these pollutants found in water, sediments and biota, especially fish and

shellfish. For mercury, fate and transport modeling and exposure assessments predict that the
Executive Summary

Deposition of Air Pollutants to the Great Waters – 3rd Report to Congress 2000 Page v

anthropogenic contribution to the total amount of methylmercury in fish is, in part, the result of

anthropogenic mercury releases from industrial and combustion sources increasing mercury body

burdens (i.e., concentrations) in fish. Furthermore, the consumption of fish is the dominant

pathway of exposure to methylmercury for fish-consuming humans and wildlife. However, what

is known about each stage of this process varies with each pollutant (for instance, the chemical

species of the emissions and its transformation in the atmosphere).

C Airborne emissions from local as well as distant sources, both within and outside the U.S.,

contribute pollutant loadings to waters through atmospheric deposition. Determining the relative

roles of particular sources -- local, regional, national, and possibly global, as well as

anthropogenic, natural, and re-emission of pollutants -- contributing to specific waterbodies is

complex, requiring careful monitoring, atmospheric modeling, and other analytical techniques.

Actions taken by EPA and others to control sources of Great Waters pollutants of concern appear

to have positively affected trends in pollutant concentrations measured in air, water, sediment, and biota. 

Overall deposition rates of pollutants of concern have declined slightly or remained constant. Several

pollutants of concern continue to enter the Great Waters primarily through atmospheric deposition. In

addition, long-range transport of pollutants of concern from other U.S. regions or other countries is

estimated to contribute significantly to atmospheric loadings to the Great Waters. For example, the

global reservoir of mercury (which includes mercury from both U.S. and foreign sources) is estimated to

contribute about 40 percent of the total mercury deposition to U.S. lands and waters.

Concentrations of some pollutants of concern in the water, sediment, and biota of the Great

Waters declined in recent years, whereas others were constant or variable. Concentrations of most

pollutants of concern still pose potential adverse ecological and human health effects. For example,

approximately 5 percent of the Nation’s coastal and inland watersheds include “areas of probable

concern,” meaning a watershed that is associated with a certain number of monitoring sites with sediment

contamination at levels likely to cause adverse effects. Water quality data also indicate that water quality

standards in place for drinking water supplies in the Great Waters are not being exceeded for the

pollutants of concern, but that surface water quality guidance and criteria are being exceeded for some of

the Great Waters. In addition, nationally, fish consumption advisories were in place for 39 of 56 Great

Waters waterbodies as of 1997. 

Based on current trends, EPA expects atmospheric deposition to remain a significant source of

several pollutants of concern to the Great Waters for the foreseeable future. In addition, because of the

ability of these pollutants to persist and bioaccumulate, they are expected to remain in the water,

sediments and biota for much longer. 

Implementation of existing EPA regulations is expected to further reduce emissions of mercury,

NOx, POMs, dioxins and furans, cadmium, and hexachlorobenzene. The EPA continues to implement

programs under CAA authorities and expects that pollutant emissions will be further controlled by

several rules scheduled to take effect in coming years. As a result, atmospheric deposition and loadings

of these pollutants may be significantly reduced. In addition, actions taken to voluntarily reduce

chemical use, implement pollution prevention initiatives, advance technology (e.g., alternative fuel

vehicles), and implement pollution control laws issued by States and other nations will further reduce

pollutant loadings to the Great Waters.
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Page vi Deposition of Air Pollutants to the Great Waters – 3rd Report to Congress 2000

What future directions will EPA follow to implement section

112(m)?

The EPA developed six key recommendations that will assist in meeting the objectives and

requirements of the CAA related to the Great Waters program.

• The EPA will continue to support the maintenance and expansion of efforts to monitor Great

Waters pollutants of concern in order to evaluate the relative contributions of local, regional, and

long-range transport to deposition in the U.S., as well as natural versus human-made sources.

• The EPA will continue to develop and implement regulations and pollution prevention programs

regionally and nationally, including multimedia programs, in order to reduce the impact of

sources of Great Waters pollutants of concern within the U.S.

• For Great Waters pollutants emitted by sources outside the U.S., EPA will work within

international frameworks to reduce sources of these pollutants.

• The EPA will support model development and research that establish and clarify the linkages

from emissions to atmospheric deposition to waterbody loadings to adverse public health and the

environmental effects of Great Waters pollutants of concern in order to enable effective risk

management decisions.

• The EPA will encourage and support the establishment of common baselines and measures of

progress in order to better assess trends and health of Great Waters and other waterbodies

affected by atmospheric deposition.

• The EPA will work to increase public awareness of risks of exposure to Great Waters pollutants.

These key recommendations build on the strategic themes identified in the First and Second

Reports to Congress: (1) continued implementation of the CAA to directly control emissions of Great

Waters pollutants of concern; (2) use of an integrated multimedia approach throughout the Agency,

including coordination of clean air programs with programs available under other Federal laws (e.g.,

Clean Water Act); and, (3) continued support of research activities that address the goals of the Great

Waters program.

In support of the first strategic theme, EPA will develop or assess the need for new rules and

programs under the CAA, including maximum achievable control technology (MACT) standards, section

112(c)(6) standards, as well as standards that could stem from the residual risk program, the utility air

toxics determination, and the integrated urban air toxics strategy. As appropriate, EPA will consider the

impacts of atmospheric deposition in developing standards under these authorities. In addition, EPA will

ensure the timely implementation of NOx control programs already in place and will encourage

innovative, nonregulatory approaches to reducing NOx emissions and other sources of atmospheric

nitrogen. 

This report describes a number of multimedia and cross-program initiatives (e.g., Clean Water

Action Plan, Persistent Bioaccumulative Toxics Initiative) that are in line with EPA’s second strategic

theme for the Great Waters program. Some of these initiatives, such as the pulp and paper cluster rule,

will produce tangible environmental benefits within the near future. Other initiatives, such as

development of multimedia models in support of TMDL determinations and completion of the
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Deposition of Air Pollutants to the Great Waters – 3rd Report to Congress 2000 Page vii

Contaminated Sediment Non-point Source Inventory, will provide tools and data resources that will help

EPA target future pollution control activities.

There has been substantial progress in research activities relevant to the Great Waters program

since the Second Report to Congress. However, important information gaps remain, and there are critical

limitations to current atmospheric monitoring and modeling capabilities. Consistent with the third

strategic theme, therefore, EPA will initiate and continue to support scientific research to fill these

critical gaps, including the following activities:

• Support research to examine and quantify the ecological effects of atmospheric deposition and to

better quantify the water quality benefits of air pollution controls;

• Expand the geographic coverage and consistency of waterbody monitoring to enable more

accurate characterizations of the extent of contamination and ecosystem effects due to

atmospheric deposition; 

• Encourage and support interagency coordination to better quantify the indirect loadings of

atmospheric deposition to the Great Waters through the development of tools that can quantify

watershed transport of pollutants of concern;

• Continue to support the development of modeling tools which address the transport and fate of

pollutants in ecosystems and characterize risk, including research to clarify mechanisms of

mercury methylation so as to better predict and manage ecosystems at risk;

C Develop reliable approaches for quantifying and monitoring nitrogen dry deposition and wet

organic nitrogen deposition;

• Support joint work with States and industry to fill gaps in emissions information for MACT

source categories and further refine emissions measurement methods, inventories, and modeling

for Great Waters pollutants of concern;

C Support research on viable prevention and controls for sources of pollutants of concern; 

• Encourage and support greater coordination and expansion of monitoring networks to assess

deposition of pollutants to coastal waters, to assess the contribution of long-range transport to

deposition in the U.S., and to evaluate the impact of agricultural and urban sources;

• Develop standard methods to monitor pollutants of concern to enable the comparison of data and

trends analyses;

• Support international efforts to quantify the transboundary contributions of pollutants of concern

and to share technology, information, and expertise with other countries on reducing releases to

the environment and on cost-effective alternatives to their use;

• Working closely with other EPA and inter-governmental efforts to address, in particular,

persistent bioaccumulative toxic pollutants, and to identify and evaluate additional pollutants

which may be of concern to the Great Waters;

• Continue research to identify additional endocrine disrupting chemicals and their associated

effects; and,
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Page viii Deposition of Air Pollutants to the Great Waters – 3rd Report to Congress 2000

• Continue coordination and support of efforts to improve the consistency of fish consumption

advisories and the awareness and understanding of advisories among populations most at risk to

exposure to the Great Waters pollutants of concern.

The EPA is committed to continuing to address air deposition of pollutants into the Nation’s

waters as a priority matter. To that end, and to assure continued coordination of the many related tasks

involved and outlined in this report, EPA will develop a detailed biennial work plan for implementation

actions beginning this year and updated every two years. As EPA develops and implements plans,

programs and initiatives with NOAA and its other Federal, State, tribal, industry and community

partners, we expect to make significant, measurable progress toward our goal of assuring the protection

of human health and the environment from adverse effects attributable to atmospheric deposition of

pollution to the Great Waters. 
Deposition of Air Pollutants to the Great Waters – 3rd Report to Congress 2000 Page ix

TABLE OF CONTENTS

PAGE

ACKNOWLEDGMENTS

EXECUTIVE SUMMARY ............................................................ i

LIST OF TABLES ................................................................. xii

LIST OF FIGURES ................................................................ xiv

LIST OF ABBREVIATIONS AND ACRONYMS ....................................... xv

I. INTRODUCTION AND BACKGROUND ....................................... I-1

A. Overview of the Great Waters Program ........................................ I-3

Definition of Great Waters .............................................. I-3

Program Participants and Organizations .................................... I-3

Government Goals Supported by the Great Waters Program and Its Partners ....... I-6

B. Pollutants of Concern ...................................................... I-7

C. Goals of the Third Report to Congress ........................................ I-13

II. ENVIRONMENTAL PROGRESS ............................................ II-1

Pollutant-Specific Changes .................................................... II-3

Mercury and Compounds ............................................... II-4

Other Metals (Lead and Cadmium) ...................................... II-19

Combustion Emissions ............................................... II-31

Nitrogen and Compounds ............................................. II-40

Banned and Restricted Use Substances ................................... II-58

Cross-Pollutant Trends ...................................................... II-67

Fish Consumption Advisories .......................................... II-68

Water Quality Assessments ............................................ II-69

NOAA’s National Status and Trends Program ............................. II-70

National Sediment Quality Survey ...................................... II-73

Chesapeake Bay Program ............................................. II-73

Lake Champlain Sediment Toxics Assessment Program ..................... II-75

San Francisco Estuary Regional Monitoring Program for 

Trace Substances ............................................. II-76

III. MAJOR PROGRAMS AND ACTIVITIES ..................................... III-1

A. National Programs and Activities ............................................ III-3

Multimedia Activities ................................................. III-4

Hazardous Air Pollutant (HAP) Controls ................................. III-11

Stationary Source Controls Addressing NOx............................... III-17

Mobile Source Program Activities ...................................... III-29

Ozone and PM NAAQS and Proposed Regional Haze Rule ................... III-30

Other National Programs .............................................. III-30

B. Regional and Waterbody-Specific Programs .................................. III-34

Great Lakes Program ................................................. III-35

Lake Champlain Basin Program ........................................ III-37

Chesapeake Bay Program ............................................. III-38

Gulf of Mexico Program .............................................. III-41
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Page x Deposition of Air Pollutants to the Great Waters – 3rd Report to Congress 2000

PAGE

National Estuary Program ............................................. III-42

NOAA Activities .................................................... III-48

Ozone Transport Commission (OTC) .................................... III-49

C. State, Local, and Tribal Activities .......................................... III-51

State and Local Activities ............................................. III-51

Tribal Activities ..................................................... III-60

D. Industry Activities ....................................................... III-63

Chlor-alkali Industry Mercury Reduction Goal ............................. III-63

Voluntary Mercury Agreement with Northwest Indiana Steel Mills ............ III-64

American Hospital Association MOU .................................... III-64

Electric Power Research Institute Studies ................................. III-65

E. Work with Other Countries ................................................ III-66

Canada-U.S. Binational Toxics Strategy .................................. III-66

International Joint Commission ......................................... III-69

United Nations Economic Commission for Europe LRTAP Protocols

on Heavy Metals and POPs ..................................... III-70

United Nations Environment Program Global POPs Initiative ................. III-71

NAFTA Commission on Environmental Cooperation Sound Management

 of Chemicals Program ............................................ III-71

U.S.-Canada Air Quality Agreement ..................................... III-72

IV. SCIENCE AND TOOLS .................................................... IV-1

What Major Advancements Have Occurred Since the Second Report? .................. IV-2

Emission Inventories .................................................. IV-2

Ambient Air and Deposition Monitoring Networks .......................... IV-4

Other Environmental Monitoring Networks and Databases .................... IV-8

Environmental Transport and Fate ...................................... IV-11

Measuring and Monitoring Techniques ................................... IV-20

Exposure and Effects Research ......................................... IV-21

V. NEXT STEPS FOR THE GREAT WATERS PROGRAM ........................ V-1

A. Pollutant Sources ........................................................ V-4

Findings and Conclusions .............................................. V-4

Recommendations for Continued and Further Action ......................... V-5

B. Contribution of Atmospheric Deposition to Pollutant Loadings in the Great Waters .... V-8

Findings and Conclusions .............................................. V-8

Recommendations for Continued and Further Action ........................ V-10

C. Environmental and Public Health Effects ..................................... V-11

Finding and Conclusions .............................................. V-11

Recommendations for Continued and Further Action ........................ V-12

D. Exceedances of Water Quality or Drinking Water Standards ..................... V-14

Finding and Conclusions .............................................. V-14

Recommendations for Continued and Further Action ........................ V-14

E. Summary and Key Recommendations ........................................ V-16

REFERENCES

INDEX OF WATERBODIES
Table of Contents

Deposition of Air Pollutants to the Great Waters – 3rd Report to Congress 2000 Page xi

APPENDIX A: Major Sources of Information – Publications and Internet Sites

APPENDIX B: Detailed Breakdown of Air Emissions Inventory by Pollutant for Source

Categories Emitting Less than One Percent of Total U.S. Emissions

APPENDIX C: Fish Consumption Advisories Issued for the Great Waters

APPENDIX D: Names of Numbered Sites from Figure II-17: Locations of Watersheds

Designated as Areas of Probable Concern
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Page xii Deposition of Air Pollutants to the Great Waters – 3rd Report to Congress 2000
Deposition of Air Pollutants to the Great Waters – 3rd Report to Congress 2000 Page xiii

LIST OF TABLES

CHAPTER I PAGE

Table I-1: Uses/Sources and U.S. Regulatory Status of Great Waters Pollutants of 

Concern .......................................................... I-9

Table I-2: EPA Multimedia and Cross-program Management of the Great Waters

Pollutants of Concern .............................................. I-10

Table I-3: Great Waters Pollutants of Concern Addressed by Selected Waterbody, Regional, 

and International Activities .......................................... I-12

CHAPTER II

Table II-1: National Anthropogenic Mercury Air Emissions ............................ II-7

Table II-2: Preliminary Estimates of Total Atmospheric Mercury Deposition to 

Lake Michigan ...................................................... II-13

Table II-3: Mercury Sources Identified in Mass Balance Studies (By Percent Contribution) . . II-14

Table II-4: National Anthropogenic Lead Air Emissions .............................. II-23

Table II-5: National Anthropogenic Cadmium Air Emissions .......................... II-25

Table II-6: Trace Metals Inputs to the Chesapeake Bay ............................... II-26

Table II-7: Direct Atmospheric Deposition of Lead and Cadmium to Massachusetts 

Bay ............................................................ II-27

Table II-8: Temporal Changes in Metal Concentrations in Chesapeake Bay 

Tributaries Based on Sediment Cores ................................. II-29

Table II-9: Cadmium and Lead in Sediments of the Chesapeake Bay Mainstem ............ II-30

Table II-10: Lead and Cadmium in Horseshoe Crab Eggs from Delaware Bay .............. II-30

Table II-11: National Anthropogenic Dioxin and Furan TEQ Air Emissions ................ II-32

Table II-12: Current Rates of Dioxins and Furans Accumulation in Great Lakes 

Sediments ...................................................... II-33

Table II-13: Modeled Air Deposition, Depositional Flux, and Waterborne Inputs of Dioxins 

and Furans to the Great Lakes ....................................... II-33

Table II-14: National Anthropogenic 16-PAH Air Emissions ............................ II-35

Table II-15: Sum of Wet and Dry Deposition of PAHs onto Massachusetts Bay ............ II-38

Table II-16: Estimates of PAH Inputs to the Chesapeake Bay ........................... II-39

Table II-17: Annual PAH Inputs to and Losses from the Chesapeake Bay .................. II-39

Table II-18: Common Forms of Atmospheric Nitrogen ................................ II-42

Table II-19: Transfer of Atmospheric Deposition Nitrogen (ADN) from Various Watershed 

Areas .......................................................... II-52

Table II-20: Transfer of Atmospheric Deposition Nitrogen (ADN) from Watersheds to 

Several Bays and Estuaries ......................................... II-52

Table II-21: Atmospheric Nitrogen Loads Relative to Total Nitrogen Loads in Selected 

Great Waters .................................................... II-53

Table II-22: National Anthropogenic PCB Air Emissions .............................. II-59

Table II-23: IADN Loading Estimates of PCBs (wet and dry) for the Great Lakes ........... II-60

Table II-24: IADN Loading Estimates of DDT (wet and dry) to the Great Lakes ............ II-64

Table II-25: Current and Maximum Rates of Toxaphene Accumulation in Great Lakes 

Sediments ...................................................... II-66

Table II-26: Modeled Air Deposition, Depositional Flux, and Waterborne Inputs of HCB to 

the Great Lakes .................................................. II-67

Table II-27: Trends of Pollutant Concentrations in Mussel Watch Project (1986-1996) ....... II-72
List of Tables

Page xiv Deposition of Air Pollutants to the Great Waters – 3rd Report to Congress 2000

PAGE

Table II-28: Percentages of 1996 Samples that Exceeded Guidelines in the San

Francisco Estuary ................................................ II-76

CHAPTER III

Table III-1: Source Categories With Effective Compliance Dates and Anticipated Reductions

of HAP Emissions ................................................ III-11

Table III-2: Proposed and Final Rules Affecting Pollutants of Concern ................... III-13

Table III-3: Emission Reductions Expected from Control Equipment Used to Retrofit A 

Typical Existing MWC Plant ....................................... III-17

Table III-4: Emission Reductions Expected from Existing HMIWI ....................... III-18

Table III-5: Emission Reductions Expected at New HMIWI after 5 Years of NSPS 

Implementation .................................................. III-19

Table III-6: Recent Regulations Affecting Stationary Source NOx Emissions ............... III-20

Table III-7: Pounds of Pesticides Collected through Clean Sweep Programs 

Nationwide ..................................................... III-57

Table III-8: U.S. BNS Challenge Goals and Activities for Level I Substances .............. III-68
Deposition of Air Pollutants to the Great Waters – 3rd Report to Congress 2000 Page xv

LIST OF FIGURES

CHAPTER I PAGE

Figure I-1: Pollutant Transport Pathways to Waterbodies ................................ I-1

Figure I-2: Locations of the Great Waters ............................................ I-3

CHAPTER II

Figure II-1: Atmospheric Release, Transport, and Deposition Processes .................... II-2

Figure II-2: Monitoring Sites of the Mercury Deposition Network – 1999 ................. II-10

Figure II-3: 1993 Lead Emissions in the Great Lakes Region ........................... II-22

Figure II-4: 1982 Lead Emissions in the Great Lakes Region ........................... II-22

Figure II-5: 1993 Cadmium Sources in the Great Lakes Region ......................... II-23

Figure II-6: Chesapeake Bay Tidal and Non-tidal Waters .............................. II-26

Figure II-7: IADN Loading Estimates of B[a]P to the Great Lakes ....................... II-37

Figure II-8: National NOx Emission Trends, 1985-1996 ............................... II-45

Figure II-9: 1996 NOx Emissions by State .......................................... II-46

Figure II-10: 1996 National Anthropogenic NOx Emissions by Principle Source 

Category ....................................................... II-45

Figure II-11: Estimated Nitrogen Emissions to Air by Principle Source Category in North 

Carolina - Anthropogenic and Biogenic ............................... II-47

Figure II-12: Estimated Inorganic Nitrogen Wet Deposition, 1997 ........................ II-48

Figure II-13: Nitrogen Wet Deposition in the Chesapeake Bay Watershed .................. II-50

Figure II-14: Nitrogen Wet Deposition in the Great Lakes Watersheds ..................... II-50

Figure II-15: Nitrogen Wet Deposition in the Lake Champlain Watershed .................. II-50

Figure II-16: Expected Year that Great Waters Pesticides will be Below Current Detection 

Limits in the Great Lakes Atmosphere ................................ II-64

Figure II-17: Locations of Areas of Probable Concern Within Watersheds .................. II-74

CHAPTER III

Figure III-1: Projected National NOx Emission Trends, 1996-2010 ....................... III-19

Figure III-2: The 43 Areas of Concern in the Great Lakes Basin ......................... III-36

CHAPTER IV

Figure IV-1: Monitoring Sites of Ambient Air and Deposition Monitoring Networks Measuring 

Pollutants of Concern .............................................. IV-5

Figure IV-2: Revised Principal Airshed for the Chesapeake Bay ......................... IV-15
List of Figures

Page xvi Deposition of Air Pollutants to the Great Waters – 3rd Report to Congress 2000
Deposition of Air Pollutants to the Great Waters – 3rd Report to Congress 2000 Page xvii

ABBREVIATIONS AND ACRONYMS

ADN Atmospheric deposition nitrogen

AEOLOS Atmospheric Exchange Over Lakes and Ocean Surfaces

AIEO American Indian Environmental Office

AILESP American Indian Lands Environmental Support Project

AIRMoN Atmospheric Integrated Research Monitoring Program

AOC Areas of concern

APC Areas of probable concern

AQC Air Quality Committee 

ARL Air Resources Laboratory

ATSDR Agency for Toxic Substances and Disease Registry

BACT Best available control technology

BASMAA Bay Area Stormwater Management Agencies Association

BNS Binational Toxics Strategy

BRACE Bay Regional Atmospheric Chemistry Experiment

CAA Clean Air A ct

CASTNet Clean Air Status and Trends Network

CBADS Chesapeake Bay Atmospheric Deposition Study

CBEP Community-Based Environmental Program

CBP Chesapeake Bay Program

CBPO Chesapeake Bay Program Office

CEC Commission on Environmental Cooperation

CENR Committee on Environment and Natural Resources 

CHPAC Children’s Health Protection Advisory Committee

CMAQ Community multi-scale air quality

CTDEP Connecticut Department of Environmental Protection

CVAFS Cold vapor atomic fluorescence spectrometry

CWA Clean Water Act

CZM Coastal zone management

DC District of Columbia

DDD 1,1'-(2,2-dichloroethylidene)bis(4-chlorobenzene)

DDE 1,1'-(dichloroethenylidene)bis(4-chlorobenzene)

DDT 1,1'-(2,2,2-trichloroethylidene)bis(4-chlorobenzene)

DIN/SRP Dissolved inorganic nitrogen to soluble reactive phosphorus

DNREC Department of Natural Resources and Environmental Conservation

EAGLE Effects on Aboriginals from the Great Lakes Environment 

EDSTAC Endocrine Disruptor Screening and Testing Advisory Committee

EEGLE Episodic Events/Great Lakes Experiment

EGU Electric generation units

EMAP Environmental Monitoring and Assessment Program

EPCHC Environmental Protection Committee of Hillsborough County

EOM Extractable organic matter

EPA Environmental Protection Agency

EPRI Electric Power Research Institute

FAMS Florida Atmospheric Mercury Study

FCP Fish Contamination Program

FDEP Florida Department of Environmental Protection

FIFRA Federal Insecticide, Fungicide, and Rodenticide Act

FIP Federal implementation plan

FR Federal Register
Abbreviations and Acronyms

Page xviii Deposition of Air Pollutants to the Great Waters – 3rd Report to Congress 2000

g Gram

GIS Geographic Information System

GLNPO Great Lakes National Program Office

GLWQA Great Lakes Water Quality Agreement

GMPO Gulf of Mexico Program Office

GPRA Government Performance and Results Act

HAP Hazardous air pollutant

HCB Hexachlorobenzene

HCH Hexachlorocyclohexane

HMIWI Hazardous/medical/infectious waste incinerators

HNO3 Nitric acid

HYSPLIT Hybrid single particle Lagrangian integrated trajectory

IADN Integrated Atmospheric Deposition Network

IAQAB International Air Quality Advisory Board

IBI Index of Biotic Integrity

IDEM Indiana Department of Environmental Management

IJC International Joint Commission

INC International Negotiating Committee

kg Kilogram

LaMP Great Lakes Lakewide Management Plans

LAER Lowest achievable emission rate

LCBP Lake Champlain Basin Program

LISS Long Island Sound Study

LMMBS Lake Michigan Mass Balance Study

LRTAP Europe Long-Range Transboundary Air Pollution

MACT Maximum achievable control technology

MCL Maximum contaminant level

MCM Mercury cycling model

MDEQ Michigan Department of Environmental Quality

MDN Mercury Deposition Network

MOU Memorandum of Understanding

MPCA Minnesota Pollution Control Agency

MTRL Maximum tissue residue level

MWC Municipal waste combustors

N Nitrogen

NAAEC North American Agreement on Environmental Cooperation

NAAQS National ambient air quality standard

NADP National Atmospheric Deposition Program

NADP-MDN National Atmospheric Deposition Program - Mercury Deposition Network

NADP-NTN National Atmospheric Deposition Program - National Trends Network

NAFTA North American Free Trade Agreement

NCSU North Carolina State University

NDAMN National Dioxin Air Monitoring Network

NEP National Estuary Program

NERRS National Estuarine Research Reserve System 

NESCAUM Northeast States and Eastern Canadian Provinces Mercury Study

NH3 Ammonia

NH4

+ Ammonium

NHx Reduced nitrogen compounds (e.g., ammonia, ammonium)

NLFWA National Listing of Fish and Wildlife Advisories
Abbreviations and Acronyms

Deposition of Air Pollutants to the Great Waters – 3rd Report to Congress 2000 Page xix

NLEV National low emission vehicle

NO Nitric oxide

NO2 Nitric dioxide

NO3 Aerosol nitrate

NOAA National Oceanic and Atmospheric Administration

NOEL No observed effects level

NOx Oxides of nitrogen

NS&T National Status and Trends

NSI National Sediment Inventory

NSPS New source performance standards

NSQS National Sediment Quality Survey

NTI National Toxics Inventory

NORBIC North Business-Industrial Council

OAP Office of Atmospheric Programs

OAQPS Office of Air Quality Planning and Standards

OAR Office of Radiation

OC Organochlorine chemical

OCHP Office of Children’s Health Protection

OMS Office of Mobile Sources

OPPTS Office of Pollution Prevention and Toxics

ORD Office of Research and Development

OTAG Ozone Transport Assessment Group

OTAQ Office of Transportation and Air Quality

OTC Ozone Transport Commission

OTR Ozone Transport Region

OW Office of Water

PAH Polycyclic aromatic hydrocarbon

PBT Persistent bioaccumulative toxic

PCB Polychlorinated biphenyl

PCDD Polychlorinated dibenzo-p-dioxin

PCDF Polychlorinated dibenzofuran

PEL Probable effects level

PM Particulate matter

POM Polycyclic organic matter

POP Persistent organic pollutant

RACT Reasonably available control technology

RADM Regional Atmospheric Deposition Model

RAP Regional action plan

RELMAP Regional Lagrangian Model of Air Pollution

R-EMAP Regional Environmental Monitoring and Assessment Program

REMSAD Regulatory Modeling System for Aerosols and Deposition

SAB Science Advisory Board

SAV Submerged aquatic vegetation

SFEI San Francisco Estuary Institute

SFEP San Francisco Estuary Project

SIP State implementation plan

SMOC Sound management of chemicals

SoFAMMS South Florida Atmospheric Mercury Monitoring Study

SVOC Semi-volatile organic compound

SWFWMD Southwest Florida Water Management District
Abbreviations and Acronyms

Page xx Deposition of Air Pollutants to the Great Waters – 3rd Report to Congress 2000

SWMP System-Wide Monitoring Program

TBNEP Tampa Bay National Estuary Program

TEQ Toxic equivalent quantity

TLRI Toxics Loading and Release Inventory

TMDL Total maximum daily load

tpy Tons per year

TRANSCO Transfer coefficient

TRI Toxic Release Inventory

TRIM Total Risk Integrated Methodology

TSCA Toxic Substances Control Act

UNC-CH University of North Carolina at Chapel Hill

UN-ECE United Nations Economic Commission for Europe

UNEP United Nations Environment Program

US United States

USGS U.S. Geological Survey

VOC Volatile organic compound

WLSSD Western Lake Superior Sanitary District

WMNP Waste Minimization National Plan

WMPT Waste Minimization Prioritization Tool

WQB Water Quality Board

WRDA Water Resources Development Act

yr Year