[House Hearing, 108 Congress]
[From the U.S. Government Publishing Office]



 
                      MERCURY EMISSIONS: STATE OF
                       THE SCIENCE AND TECHNOLOGY

=======================================================================

                                HEARING

                               BEFORE THE

                SUBCOMMITTEE ON ENVIRONMENT, TECHNOLOGY,
                             AND STANDARDS

                          COMMITTEE ON SCIENCE
                        HOUSE OF REPRESENTATIVES

                      ONE HUNDRED EIGHTH CONGRESS

                             FIRST SESSION

                               __________

                            NOVEMBER 5, 2003

                               __________

                           Serial No. 108-34

                               __________

            Printed for the use of the Committee on Science


     Available via the World Wide Web: http://www.house.gov/science

                                 _____

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                          COMMITTEE ON SCIENCE

             HON. SHERWOOD L. BOEHLERT, New York, Chairman
LAMAR S. SMITH, Texas                RALPH M. HALL, Texas
CURT WELDON, Pennsylvania            BART GORDON, Tennessee
DANA ROHRABACHER, California         JERRY F. COSTELLO, Illinois
JOE BARTON, Texas                    EDDIE BERNICE JOHNSON, Texas
KEN CALVERT, California              LYNN C. WOOLSEY, California
NICK SMITH, Michigan                 NICK LAMPSON, Texas
ROSCOE G. BARTLETT, Maryland         JOHN B. LARSON, Connecticut
VERNON J. EHLERS, Michigan           MARK UDALL, Colorado
GIL GUTKNECHT, Minnesota             DAVID WU, Oregon
GEORGE R. NETHERCUTT, JR.,           MICHAEL M. HONDA, California
    Washington                       CHRIS BELL, Texas
FRANK D. LUCAS, Oklahoma             BRAD MILLER, North Carolina
JUDY BIGGERT, Illinois               LINCOLN DAVIS, Tennessee
WAYNE T. GILCHREST, Maryland         SHEILA JACKSON LEE, Texas
W. TODD AKIN, Missouri               ZOE LOFGREN, California
TIMOTHY V. JOHNSON, Illinois         BRAD SHERMAN, California
MELISSA A. HART, Pennsylvania        BRIAN BAIRD, Washington
JOHN SULLIVAN, Oklahoma              DENNIS MOORE, Kansas
J. RANDY FORBES, Virginia            ANTHONY D. WEINER, New York
PHIL GINGREY, Georgia                JIM MATHESON, Utah
ROB BISHOP, Utah                     DENNIS A. CARDOZA, California
MICHAEL C. BURGESS, Texas            VACANCY
JO BONNER, Alabama
TOM FEENEY, Florida
RANDY NEUGEBAUER, Texas
                                 ------                                

         Subcommittee on Environment, Technology, and Standards

                  VERNON J. EHLERS, Michigan, Chairman
NICK SMITH, Michigan                 MARK UDALL, Colorado
GIL GUTKNECHT, Minnesota             BRAD MILLER, North Carolina
JUDY BIGGERT, Illinois               LINCOLN DAVIS, Tennessee
WAYNE T. GILCHREST, Maryland         BRIAN BAIRD, Washington
TIMOTHY V. JOHNSON, Illinois         JIM MATHESON, Utah
MICHAEL C. BURGESS, Texas            ZOE LOFGREN, California
VACANCY                              RALPH M. HALL, Texas
SHERWOOD L. BOEHLERT, New York

                ERIC WEBSTER Subcommittee Staff Director
            MIKE QUEAR Democratic Professional Staff Member
            JEAN FRUCI Democratic Professional Staff Member
                 OLWEN HUXLEY Professional Staff Member
                MARTY SPITZER Professional Staff Member
               SUSANNAH FOSTER Professional Staff Member
       AMY CARROLL Professional Staff Member/Chairman's Designee
                ADAM SHAMPAINE Majority Staff Assistant
                MARTY RALSTON Democratic Staff Assistant



                            C O N T E N T S

                            November 5, 2003

                                                                   Page
Witness List.....................................................     2

Hearing Charter..................................................     3

                           Opening Statements

Statement by Representative Vernon J. Ehlers, Chairman, 
  Subcommittee on Environment, Technology, and Standards, 
  Committee on Science, U.S. House of Representatives............     9
    Written Statement............................................    10

Statement by Representative Mark Udall, Minority Ranking Member, 
  Subcommittee on Environment, Technology, and Standards, 
  Committee on Science, U.S. House of Representatives............    10
    Written Statement............................................    11

Prepared Statement by Representative Nick Smith, Member, 
  Subcommittee on Environment, Technology, and Standards, 
  Committee on Science, U.S. House of Representatives............    12

                               Witnesses:

Dr. Thomas A. Burke, Professor and Associate Chair, Department of 
  Health Policy and Management, Johns Hopkins University, 
  Bloomberg School of Public Health
    Oral Statement...............................................    13
    Written Statement............................................    15

Dr. David P. Krabbenhoft, Research Scientist, United States 
  Geological Survey
    Oral Statement...............................................    17
    Written Statement............................................    19

Dr. George R. Offen, Senior Technical Leader, Air Emission and 
  By-Product Management, Electric Power Research Institute
    Oral Statement...............................................    23
    Written Statement............................................    25

Mr. Kenneth A. Colburn, Executive Director, Northeast States for 
  Coordinated Air Use Management
    Oral Statement...............................................    29
    Written Statement............................................    31

Discussion
  Lessons Learned From the State of Florida Research.............    34
  The Difference Between Methylmercury and Elemental Mercury.....    34
  Human Response to Methylmercury Exposure.......................    35
  Fresh Water vs. Marine Water...................................    35
  Development of Specific Technologies for Mercury Abatement.....    36
  Federal Regulation's Effect on Mercury Reduction...............    37
  Relationship Between Government Regulation and Technology 
    Development..................................................    37
  How Federal Agencies Are Responding............................    38
  Thimerosal.....................................................    39
  What Happens to Mercury When It Enters the Natural Environment.    40
  Scientific Basis for EPA Standard..............................    41
  Mercury in the Chesapeake Bay..................................    41
  The Basis for National Academy of Science's Recommendation.....    43
  The Effect of Regulation on Innovation.........................    44
  Department of Energy Effort to Create New Technologies.........    45
  The Cause of the Decline of Mercury in the Florida Study.......    45
  Eliminating Mercury Emissions..................................    46
  Tracking Mercury Once It Has Been Emitted From a Plant.........    47
  Global, Local, and Regional Sources of Mercury.................    48
  Fish Consumption in the Seychelle Island Studies...............    50
  Effects on Wildlife............................................    50
  Closing Comments...............................................    52

           Appendix 1: Biographies and Financial Disclosures

Dr. Thomas A. Burke, Professor and Associate Chair, Department of 
  Health Policy and Management, Johns Hopkins University, 
  Bloomberg School of Public Health
    Biography....................................................    54
    Financial Disclosure.........................................    55

Dr. David P. Krabbenhoft, Research Scientist, United States 
  Geological Survey
    Biography....................................................    56

Dr. George R. Offen, Senior Technical Leader, Air Emission and 
  Byproduct Management, Electric Power Research Institute
    Biography....................................................    57
    Financial Disclosure.........................................    58

Mr. Kenneth A. Colburn, Executive Director, Northeast States for 
  Coordinated Air Use Management
    Biography....................................................    59
    Financial Disclosure.........................................    60

             Appendix 2: Additional Material for the Record

Letter from Kenneth A. Colburn, Executive Director, NESCAUM, 
  dated November 21, 2003, to Hon. Vern Ehlers, Chairman.........    64

Letter from George R. Offen, Sr. Technical Leader, Emissions/
  Combustion Product Management, EPRI, dated January 8, 2004.....    66

Modeling the Atmospheric Fate and Transport of Mercury Over North 
  America, by Christian Seigneur, Krish Vijayaraghavan, Kristen 
  Lohman, and Prakash Karamchandani..............................    69

Global Source Attribution for Mercury Deposition in the United 
  States, by Christian Seigneur, Krish Vijayaraghavan, Kristen 
  Lohman, Prakash Karamchandani, and Courtney Scott..............    80

Comments by The Annapolis Center for Science-Based Public Policy.    96


         MERCURY EMISSIONS: STATE OF THE SCIENCE AND TECHNOLOGY

                              ----------                              


                      WEDNESDAY, NOVEMBER 5, 2003

                  House of Representatives,
      Subcommittee on Environment, Technology, and 
                                         Standards,
                                      Committee on Science,
                                                    Washington, DC.

    The Subcommittee met, pursuant to call, at 2:08 p.m., in 
Room 2318 of the Rayburn House Office Building, Hon. Vernon J. 
Ehlers [Chairman of the Subcommittee] presiding.



                            hearing charter

         SUBCOMMITTEE ON ENVIRONMENT, TECHNOLOGY, AND STANDARDS

                          COMMITTEE ON SCIENCE

                     U.S. HOUSE OF REPRESENTATIVES

                      Mercury Emissions: State of

                       the Science and Technology

                      wednesday, november 5, 2003
                          2:00 p.m.-4:00 p.m.
                   2318 rayburn house office building

Purpose

    On November 5, 2003 at 2:00 p.m., the Subcommittee on Environment, 
Technology, and Standards of the House Science Committee will hold a 
hearing on that state of the science and technology regarding mercury 
emissions. The subcommittee will hear testimony on the health effects 
of mercury, the transport and fate of mercury in the environment, and 
the technologies that are being developed to control mercury emissions 
from coal-fired power plants.
    The Committee plans to explore several questions, including:

         What do we know about the relationship between 
        mercury exposure from fish consumption and adverse human health 
        effects?

         To what extent is mercury deposition in the 
        environment local, regional, or global?

         What do we know about how different kinds of mercury 
        become available in the environment in a manner that can 
        adversely affect human health? Is there a difference between 
        new and old mercury and between anthropogenic and naturally 
        produced mercury?

         What technologies are available or being developed to 
        control mercury pollution from power plants? What do we know 
        about the effectiveness and cost of these technologies?

Witnesses

Dr. Thomas Burke, Professor and Associate Chair, Department of Health 
Policy and Management, Johns Hopkins University Bloomberg School of 
Public Health. Dr. Burke served as a member of the National Academy of 
Sciences' Committee on the Toxicological Effects of Mercury. He 
received his Ph.D. in epidemiology from the University of Pennsylvania.

Dr. David Krabbenhoft, Research Scientist, United States Geological 
Survey. Dr. Krabbenhoft is a principal investigator on the Mercury 
Experiment to Assess Atmospheric Loading in Canada and the U.S. 
(METAALICUS) project. He received his Ph.D. in geochemistry and 
hydrogeology from the University of Wisconsin-Madison.

Dr. George Offen, Senior Technical Leader, Air Emission and Byproduct 
Management, Electric Power Research Institute (EPRI), the research arm 
of the utility industry. Dr. Offen manages EPRI's research and 
development program to reduce nitrogen oxides, sulfur dioxide 
particulate and toxic emissions from utilities. He received his Ph.D. 
in mechanical engineering from Stanford University.

Mr. Ken Colburn, Executive Director, Northeast States for Coordinated 
Air Use Management (NESCAUM). Prior to joining NESCAUM, Mr. Colburn 
served as New Hampshire's air director. He received his M.B.A. from the 
University of New Hampshire.

General Background

    Under the Clean Air Act, the Environmental Protection Agency (EPA) 
is required to regulate mercury emissions from coal-fired power plants. 
Under a consent decree, the agency has agreed to promulgate a Maximum 
Available Control Technology (MACT) regulation by December 15, 2003. At 
the same time, the agency has proposed, through the Clear Skies Act, to 
regulate mercury emissions as part of a multi-pollutant trading scheme, 
and several other multi-pollutant bills are also pending in Congress.
    There is significant debate about how and to what extent mercury 
emissions should be regulated. There are many critical science and 
technology questions that underpin this debate. These include: what do 
we know about the adverse health effects of mercury?; to what extent do 
mercury emissions deposit locally?; is newly deposited mercury more 
reactive than legacy mercury?; what is the state of technology 
development to control and monitor mercury? The state of the science 
and technology must be well understood in determining the best course 
to follow in mercury regulation.

Issues

         Do the levels at which the U.S. population is exposed 
        to mercury through fish consumption have an adverse health 
        effect?

    According to the Centers for Disease Control, eight percent of U.S. 
women of childbearing age have mercury blood levels that exceed those 
considered safe by the EPA. People are exposed to mercury through 
consumption of contaminated fish. In 2000, a panel of the National 
Research Council (the operating agency of the National Academy of 
Sciences) assessed the state of the science regarding the health 
effects of methylmercury from fish consumption. (Methylmercury is the 
form of mercury that accumulates in the food chain.) The panel examined 
epidemiological studies, animal studies, and other relevant data and 
concluded that there is an adverse health effect from methylmercury 
through fish consumption. However, in 2003, an update of one of the 
largest epidemiological studies, conducted in the Seychelles Islands, 
showed no effect from fish consumption.

         Is mercury deposition local, regional or global?

    The extent to which mercury deposition is local is an important 
factor in determining whether mercury emissions should be reduced 
through a trading scheme or at every plant. Trading schemes assume that 
the benefit will be the same regardless of where the emissions 
reductions are achieved, i.e., that there is little or no local impact 
of the pollutant. The science of mercury cycling through the 
environment is complex, and deposition patterns depend on the form of 
the mercury. Studies have shown mercury deposition far from sources, 
demonstrating that deposition can be global. However, there appears to 
be a gradient of deposition, with highest deposition downwind and close 
to sources. The hearing will examine what we know about the local 
effects of mercury emissions from power plants.

         Would slowing emissions of mercury from power plants 
        decrease mercury levels in fish?

    There are large amounts of legacy mercury (from both man-made and 
natural sources) already in the environment. Because of this, critics 
of regulation argue that any reduction in current emissions will be 
overwhelmed by mercury already in the environment. However, recent 
research results suggest that new mercury may be more active than old 
mercury, indicating that achieving reductions now would have an effect 
on levels in fish. Additionally, mercury emissions from municipal and 
medical waste incinerators have been regulated since the mid-90s, and 
in Florida (where there are a large number of these incinerators), 
levels of mercury in wildlife have decreased substantially since the 
regulations were put in place. The hearing will examine what we know 
about the relative reactivity of new mercury vs. legacy mercury.

         What levels of reductions are or will likely be 
        feasible?

    At some plants, mercury removal rates of more than 90 percent have 
been shown using technologies that are primarily intended to remove 
other pollutants such as sulfur dioxide, nitrogen oxides and 
particulate matter. However, the type of coal used largely determines 
the type of technology needed to remove mercury. Plants that use sub-
bituminous coal (found in the Western U.S.) will not likely see large 
reductions from existing technologies and will probably have to use a 
new technology such as activated carbon injection. The hearing will 
examine what kind of reductions will result, and at what cost, from 
existing technologies and technologies under development.

Detailed Background

Health Effects
    Mercury is widespread and persistent in the environment. At high-
level exposures, mercury is a serious neurotoxin and instances of 
population poisonings have been well documented. The U.S. population is 
primarily exposed to mercury in low doses through fish consumption (and 
not through breathing it in from the air like many other pollutants). 
The form of mercury that is found in fish is methylmercury (MeHg). In 
2000, a National Research Council (NRC--the operating agency of the 
National Academy of Sciences) panel evaluated what we know about the 
health effects of mercury. Reviewing the three major epidemiological 
studies (Faroe Islands, New Zealand and preliminary results from the 
Seychelles) as well as animal studies, the panel found that a range of 
health effects has been observed with severity varying primarily with 
the size of the dose. The report stated that the fetus is the most 
sensitive, and prenatal exposures have been shown to interfere with the 
growth and migration of neurons and can cause irreversible damage to 
the developing central nervous system. At the low dose exposure that is 
associated with fish consumption by the mother, infants may appear 
normal during the first few months of life, but later display deficits 
in subtle neurological endpoints such as IQ. The report also noted that 
there is evidence that MeHg affects other systems as well--a 
correlation has been found between consumption of contaminated fish and 
the risk of cardiovascular disease such as acute myocardial infarction.
    The EPA has set the reference dose (RfD) for mercury based on the 
Faroe Islands study. (A reference dose is an estimate of the daily 
exposure that the human population can withstand without an appreciable 
risk of adverse effects over a lifetime--or the level of exposure that 
can be considered safe.) A recent study released by the Centers for 
Disease Control and Prevention found that approximately eight percent 
of women of childbearing age in the U.S. had mercury levels exceeding 
the level considered safe by the Environmental Protection Agency for 
protecting the fetus. Mercury contamination in fish has led health 
departments in 45 states to issue freshwater fish consumption 
advisories. These advisories warn people to limit consumption or avoid 
altogether certain species of fish from certain bodies of water.
    In the last several months, there has been significant debate about 
the health effects of mercury from fish consumption following the May 
2003 publication of the Seychelles study, which found no effect of 
mercury from fish consumption (the Faroe Islands and New Zealand 
studies did show an effect). At the time the NRC report was issued in 
2000, the panel reviewed preliminary results from the Seychelles study, 
and stated that, ``because there is a large body of scientific evidence 
showing adverse neurodevelopmental effects, including well-designed 
epidemiological studies, the committee concludes that an RfD [reference 
dose] should not be derived from a study, such as the Seychelles study, 
that did not observe any association with MeHg.''
Sources and Emissions
    There are three major sources of anthropogenic mercury emissions--
medical waste incinerators, municipal waste incinerators and coal-fired 
power plants. In addition, mercury is released from natural sources, 
such as volcanic eruptions and degassing and vaporization from the 
Earth's crust. The EPA estimates that worldwide emissions produced by 
human activities rival and may greatly exceed natural sources.
    Total anthropogenic sources in the U.S. are approximately 158 tons 
per year. Coal burning power plants are currently the biggest source of 
anthropogenic mercury pollution in the U.S., producing approximately 48 
tons per year (or 40 percent of U.S. anthropogenic emissions). The 
Federal Government does not currently regulate coal-fired utilities 
with respect to mercury. The EPA regulates the other two major sources, 
municipal and medical waste incinerators, at 90 and 94 percent 
reductions respectively.
    Annual global emissions are estimated to range between 2,000 and 
6,000 tons per year, of which China is believed to emit approximately 
1,000 tons annually.
Emissions from Coal-Fired Power Plants
    There are small amounts of mercury in coal. Once the coal is 
burned, the mercury becomes a gas and enters the atmosphere. Mercury is 
emitted from power plants in three forms--1) elemental mercury, 2) 
oxidized mercury (also called reactive mercury or ionic mercury) which 
is primarily mercury chloride, and 3) mercury attached to particulate 
matter. All three of these forms will eventually deposit in the 
environment and could cause adverse health effects, however the 
differences are important in terms of where they deposit in the 
environment and what technologies can be used to reduce them from power 
plants. The form of the mercury emission depends on the type of coal 
and the burning process. Both bituminous (Eastern) and sub-bituminous 
(Western) coal have approximately the same total quantity of mercury, 
but the form in which it is emitted varies. Bituminous coal (found 
primarily in the eastern U.S.) contains chlorine and so when this type 
of coal is burned, approximately 70-80 percent of emissions are 
oxidized mercury. Sub-bituminous coal (found primarily in the western 
U.S.) does not contain chlorine and so approximately 70-80 percent of 
emissions are elemental mercury. The amount of mercury attached to 
particles depends upon how efficient the burning process is--the less 
efficient, the more particulate mercury will be emitted. The total 
quantity of mercury emissions is similar between the various types of 
coal.
Deposition
    Where mercury deposits (locally, regionally or globally) once it is 
released from the power plant is a major source of debate because of 
its implications for regulation. If mercury deposition is primarily 
global, then regulation through a trading scheme makes sense. 
Regulation through trading programs assumes that it does not matter 
where the reductions are achieved, and that there is little or no local 
health effect from the emissions. However, if deposition is primarily 
local, then trading pollutants can lead to ``hot spots'' because 
certain plants will buy credits instead of achieving reductions. If 
there is a significant local health effect from emissions, then 
regulation should be done at each utility to address this local effect.
    In addition, if mercury circulates globally, then since the 
proportion of U.S. emissions as compared to global emissions is small, 
it would be difficult to trace unilateral emissions reductions to 
health improvements in the U.S. However, if mercury deposits locally or 
regionally, reductions in the U.S. will likely lead to health 
improvement in the U.S.
    This is an area where the science is not clear. The past 15 years 
of research have revealed widespread mercury contamination globally 
from diffuse sources. However mercury is not evenly distributed, and 
higher levels have been observed downwind from sources. The key to 
understanding this phenomenon is unraveling the complexities of how 
mercury transforms from one form to another in the environment. 
Deposition patterns also depend on the form of the mercury. Oxidized 
mercury is water-soluble and will deposit quickly, depending somewhat 
on weather conditions, likely within 60 miles of the source. Thus, the 
emission of oxidized mercury is primarily a local and regional issue. 
Elemental mercury can stay in the atmosphere for one to three years and 
enters the global pool of mercury. Eventually, all mercury in the 
atmosphere will be oxidized and deposited.
    Researchers hypothesize that there is not an even blanket of 
mercury deposition across the globe, but that near emissions sources, 
there is greater deposition and then there is a gradient of lower 
deposition rates as you move farther away from sources. This is backed 
up with data from sediments--in more remote locations, there is 
significantly less mercury. According to data from mercury monitoring 
stations nationwide, the highest deposition rates occur in the southern 
Great Lakes, the Ohio Valley, the Northeast, and scattered areas of the 
Southeast--the areas around and downwind of coal-fired power plants. 
More research is needed to clarify this issue.
Control Technologies
    The control technology that can be used to remove mercury from 
emissions depends on the type of coal burned (and thus the form of the 
mercury) as well as the plant's current emissions control technology 
configuration. Coal that has a high chlorine content (and thus produces 
oxidized mercury) can often be effectively controlled by scrubbers 
(used primarily to control sulfur dioxide). However, wet scrubbers are 
only effective at removing mercury chloride and so control can vary 
from less than 10 percent removal to greater than 90 percent removal 
depending on the type of coal burned. Fabric filters and electrostatic 
precipitators (ESP), used primarily to remove particulate matter, can 
effectively capture mercury that is attached to particles. For a wide 
variety of coal types and control configurations, recent full-scaled 
demonstrations have proven the effectiveness of powdered activated 
carbon (PAC) injection. This technology can be retrofit on existing 
boilers with minimal new capital equipment, and is effective on 
bituminous and sub-bituminous coals. However, PAC has yet to be used at 
a commercial scale.
    An associated set of issues relates to the fact that the ash 
collected at power plants is used in industrial processes such as 
concrete production. The greater the carbon content of the ash, the 
less useful it is in these industrial processes. Large amounts of 
activated carbon are used to remove elemental mercury from the 
emissions. In order to keep the ash commercially viable, both an 
electrostatic precipitator and fabric filter are required - the ESP 
removes the mercury, and the ash (without mercury) can be collected in 
the fabric filter.
    The cost of controlling mercury depends on the type of control 
technology used. Purchase of wet scrubbers, selective catalytic 
reducers, electrostatic precipitators and fabric filters are major 
capital investments, however all of these technologies achieve mercury 
reductions as a co-benefit of other pollutant reductions. The extent to 
which these technologies are used will depend on the regulation of 
these other pollutants. Powdered activated carbon (PAC) does not 
require a major capital investment, and the primary cost is the 
purchase of the activated carbon sorbent itself. It is difficult to 
estimate how much PAC will cost because it is not yet used 
commercially, however costs have been estimated to range from less than 
$1 per megawatt hour (MWh) to $3 per MWh. PAC is also a percent 
reduction technology, meaning that the same amount of activated carbon 
will reduce a certain percentage of the mercury regardless of the total 
quantity. Therefore, PAC is more cost-effective the greater the amount 
of mercury present.
Monitoring Emissions
    Measuring mercury emissions from utilities is a challenge because 
of the very small amount of mercury emitted by each source, but 
measurement technologies are improving. Currently, the best way to 
measure mercury emissions is through wet chemistry (the Ontario Hydro 
method). This method is accurate and will indicate the form of the 
mercury being emitted. The drawbacks are that it is expensive and 
measures a short snapshot in time (about two hours). Instrumentation 
methods, which continually measure mercury emissions, are currently 
under development.
Methylation
    In order to cause adverse health effects, the dissolved mercury in 
water must become methylated (transformed into a new chemical compound 
with a methyl group attached). Researchers hypothesize that it is 
sulfur-reducing bacteria that methylate mercury. More research is 
needed on what causes mercury to become methylated. Chemical, 
biological and physical elements appear to affect methylation, and the 
limiting factor varies by location. For instance, in the Florida 
Everglades, a study has shown that sulfate load is the primary driver 
of methylation, while in the San Francisco Bay, it appears that wetland 
restoration spurs methylation, and the mode is unclear.
    Once produced, methylmercury easily accumulates in the tissues of 
aquatic organisms and becomes more concentrated as it goes up the food 
chain. The concentration of a pollutant at the top of a food chain can 
be thousands or even millions of times greater than the concentration 
of the pollutant found in water. It is through fish consumption that 
mercury enters humans and other wildlife and causes health effects.

Witness Questions

Questions addressed to Dr. Thomas Burke:

         What did the National Research Council panel find 
        about the relationship between low-dose mercury exposure and 
        adverse human health effects? Are sub-populations 
        differentially affected by mercury exposure?

         To what extent have studies published since the panel 
        issued its report in 2000 altered our knowledge about the 
        health effects of mercury?

         What are the future research needs with respect to 
        understanding the health effects of mercury?

Questions addressed to Dr. David Krabbenhoft:

         What do we know about how mercury reacts in the 
        atmosphere and what determines its deposition? To what extent 
        is deposition local, regional or global?

         What do we know about the relative reactivity of old 
        vs. new mercury and anthropogenic vs. natural mercury?

         What does research tell us about the extent to which 
        reducing mercury deposition will reduce mercury levels in fish?

         What are the future research needs with respect to 
        understanding how mercury cycles in the environment?

Questions addressed to Dr. George Offen and Mr. Ken Colburn:

         To what extent do control technologies in use today 
        at utilities reduce mercury pollution from utilities? What 
        determines the effectiveness of these technologies at reducing 
        mercury emissions?

         What are the major technologies in development today 
        to control mercury emissions from utilities? What do full-scale 
        demonstrations tell us about the likely effectiveness and cost 
        of these technologies?

         What are the major barriers to development of 
        technologies to control mercury emissions from power plants?
    Chairman Ehlers. Good afternoon. I am pleased to welcome 
everyone to this afternoon's hearing on the science and 
technology underlying a vital environmental and public health 
issue: mercury pollution.
    Mr. Gutknecht just asked how I knew that he was interested 
in this issue, and I said it must be your mercurial 
disposition, which is unfair, because he is a very stable, 
solid person. But mercury has been around for a long time. We 
have been fascinated with it for a long time. And we have only, 
in the past few centuries, realized that it is a major public 
health issue.
    This hearing is particularly timely. As most of you know, 
the Environmental Protection Agency is due to release a 
proposed mercury regulation this December, and there are also 
many bills pending in Congress to regulate mercury emissions 
from utilities, including the President's Clear Skies Act.
    I am pleased to hold a hearing to examine the critical 
science and technology questions that underpin this policy 
debate. I expect that this subcommittee can serve as a forum 
for Members to undertake sober, calm, and fair-minded reviews 
of the science as Congress considers this important 
environmental and public health issue.
    In my home state of mercury--pardon me, in my home state of 
Michigan--really, I am not from another planet. In my home 
state of Michigan, mercury pollution is a growing concern. 
People are exposed to mercury through eating contaminated fish. 
And of course, we have four of the Great Lakes touching our 
shores, and we have more boats registered per capita than any 
other state, so you know we have a lot of fisherman and many 
people eating fish. Since 1988, the Michigan Department of 
Community Health has issued a fish consumption advisory for all 
of Michigan's 11,000 inland lakes as a result of mercury 
contamination. And throughout the U.S., the Centers for Disease 
Control estimate that approximately eight percent of women of 
child-bearing age have levels of mercury in their blood that 
exceed the level considered safe by the Environmental 
Protection Agency. This is a matter of special concern for 
pregnant women.
    We certainly have a problem, but the solution must be 
informed by science. We will hear today from experts from 
academia, Federal and State Government, and industry.
    These witnesses will address a wide range of science and 
technology questions that inform the mercury debate. These 
include: ``What do we know about and how precisely can we 
determine the relationship between adverse human health effects 
and mercury exposure from fish consumption? To what extent is 
mercury deposition in the environment local, regional, or 
global? What do we know about how different chemical forms of 
mercury become available in the environment in a manner that 
can adversely affect human health? And what technologies are 
available or are being developed to control mercury pollution 
from power plants?''
    There is much to discuss and discover. Today, we want to 
thoughtfully review the current state of mercury pollution 
science and technology before new policies are put into place. 
We are here to learn. I look forward to the testimony.
    [The prepared statement of Chairman Ehlers follows:]
            Prepared Statement of Chairman Vernon J. Ehlers
    Good afternoon! Welcome to this afternoon's hearing on the science 
and technology underlying a vital environmental and public health 
issue--mercury pollution. This hearing is certainly timely. As most of 
you know, the Environmental Protection Agency is due to release a 
proposed mercury regulation this December, and there are also many 
bills pending in Congress to regulate mercury emissions from utilities, 
including the President's Clear Skies Act.
    I am pleased to hold a hearing to examine the critical science and 
technology questions that underpin this policy debate. I expect that 
this subcommittee can serve as a forum for Members to undertake sober, 
calm, and fair-minded reviews of the science as Congress considers this 
important environmental and pubic health issue.
    In my home state of Michigan, mercury pollution is a growing 
concern. People are exposed to mercury through eating contaminated 
fish. Since 1988, the Michigan Department of Community Health has 
issued a fish consumption advisory for all of Michigan's 11,000 inland 
lakes as a result of mercury contamination. And throughout the U.S., 
the Centers for Disease Control estimates that approximately 8 percent 
of women of childbearing age have levels of mercury in their blood that 
exceed the level considered safe by the Environmental Protection 
Agency.
    We certainly have a problem. But the solution must be informed by 
science. We will hear today from experts from academia, Federal and 
State government, and industry.
    These witnesses will address a wide range of science and technology 
questions that inform the mercury debate. These include: What do we 
know about and how precisely can we determine the relationship between 
adverse human health effects and mercury exposure from fish 
consumption? To what extent is mercury deposition in the environment 
local, regional, or global? What do we know about how different 
chemical forms of mercury become available in the environment in a 
manner that can adversely affect human health? And, what technologies 
are available or being developed to control mercury pollution from 
power plants?
    There is much to discuss and discover. Today we want to 
thoughtfully review the current state of mercury pollution science and 
technology, before new policies are put in place. We are here to learn. 
I look forward to the testimony.

    Chairman Ehlers. The Chair now recognizes Congressman Mark 
Udall, the Ranking Minority Member on the Subcommittee, for his 
opening statement.
    Mr. Udall. Thank you, Mr. Chairman.
    I want to welcome the panel and thank our distinguished 
Chairman for convening this hearing regarding mercury emission 
science and technology issues. The United States, as the Saudi 
Arabia of coal, has used this abundant resource to our 
advantage. Coal powered our Industrial Revolution and continues 
to provide energy to our power plants. However, as we are all 
aware, the use of coal has well documented negative 
environmental and health consequences. I am very encouraged, as 
I know the Chairman is and many of you here, that emission 
rates at coal-fired power plants for sulfur dioxide and 
nitrogen oxides have been cut by more than half since 1970. But 
I believe we can, and must, do more.
    Clean air is an environmental and public health necessity. 
Mercury is a persistent, bioaccumulative toxin. In recent 
years, Federal and State governments have taken actions to 
reduce the use of mercury and to control its emission from 
medical and municipal waste incinerators. Now it is time to 
move forward with a cost-effective, rational plan to reduce 
mercury emissions from coal-fired power plants.
    According to a 1997 EPA report to Congress, coal-fired 
power plants are the greatest human source of mercury emissions 
into our air. As a result, as the Chairman mentioned, the EPA 
is currently drafting a new standard to limit mercury emissions 
from coal-fired power plants. The level of the reduction has 
not yet been determined, but we expect the regulations to be 
finalized this December for implementation in the year 2008.
    I realize that utilities and the coal industry have 
concerns about the cost of controlling these emissions and the 
efficacy and the availability of control technologies. We 
should do what we can to ensure the costs are minimized and the 
technologies are sound. I believe there is an opportunity to 
develop, manufacture, and market control technologies here in 
the U.S. and to the rest of the world. We are, of course, not 
the only nation that utilizes coal. All you have to do is look 
at the great coal reserves in China as one example. We should 
be promoting technologies, clean technologies here and abroad, 
and we should move ahead aggressively to take advantage of 
these economic opportunities associated with this goal.
    Today, our distinguished witnesses will give this committee 
some insights into the science and technology of reducing 
mercury emissions and suggest what further studies need to be 
completed in order to get the information to make knowledgeable 
policy decisions. This will help us, I believe, to get closer 
to determining how to use preventative measures to ensure that 
the risks of mercury pollution attributable to coal-fueled 
power plants are minimized, if not eliminated altogether.
    Finally, Mr. Chairman, I know that at least one group, the 
Institute of Clean Air Companies, that wishes to contribute to 
the record for this hearing. Therefore, I would ask unanimous 
consent that the record be held open for 10 days to receive 
testimony from the Institute of Clean Air Companies and any 
other groups that may wish to submit testimony.
    Chairman Ehlers. Without objection, so ordered.
    Mr. Udall. With that, Mr. Chairman, I would yield back with 
one other observation. I know you have very few political 
opponents, but I am sure there are some of them that would like 
to send you, if not to the moon, to Mercury, so we will keep in 
mind your comments earlier as we began the hearing.
    [The prepared statement of Mr. Udall follows:]
            Prepared Statement of Representative Mark Udall
    Mr. Chairman, thank you for convening this hearing regarding 
mercury emission science and technology issues.
    The United States--as the ``Saudi Arabia of coal''--has used this 
abundant resource to our advantage. Coal powered our industrial 
revolution and continues to provide energy for our power plants. 
However, as we are all aware, the use of coal has well-documented 
negative environmental and health consequences.
    I am very encouraged by the fact that emission rates at coal-fired 
power plants for sulfur dioxide and nitrogen oxides have been cut by 
more than half since 1970--but I believe we can and must do more. Clean 
air is an environmental and public health necessity.
    Mercury is a persistent, bio-accumulative toxin. In recent years, 
Federal and State governments have taken actions to reduce the use of 
mercury and to control its emission from medical and municipal waste 
incinerators. Now it is time to move forward with a cost-effective, 
rational plan to reduce mercury emissions from coal-fired power plants.
    According to a 1997 EPA report to Congress, coal-fired power plants 
are the greatest human source of mercury emissions into our air. As a 
result, the EPA is currently drafting a new standard to limit mercury 
emissions from coal-fired power plants. The level of reduction has not 
yet been determined, but we expect the regulations to be issued this 
December for implementation at the beginning of 2008.
    I realize that utilities and the coal industry have concerns about 
the cost of controlling these emissions and the efficacy and 
availability of control technologies. We should do what we can to 
ensure the costs are minimized and the technologies are sound.
    I believe there is an opportunity to develop, manufacture and 
market control technologies here in the U.S. and to the rest of the 
world. We are not the only nation that utilizes coal. We should be 
promoting cleaner technologies here and abroad, and we should move 
ahead aggressively to take advantage of the economic opportunities 
associated with this goal.
    Today, our distinguished witnesses will give this committee some 
insights into the science and technology of reducing mercury emissions 
and suggest what further studies need to be completed in order to get 
the information needed to make knowledgeable decisions. This will help 
us get closer to determining how to use preventive measures to ensure 
that the risks of mercury pollution attributable to coal-fueled power 
plants are minimized, if not eliminated altogether.
    Finally, Mr. Chairman, I know of at least one group--the Institute 
of Clean Air Companies--that wishes to contribute to the record for 
this hearing. Therefore, I ask for unanimous consent that the record be 
held open for ten days to receive testimony from the Institute of Clean 
Air Companies and any other groups that may wish to submit testimony.

    Chairman Ehlers. Thank you. Since I have asthma, I am used 
to going without oxygen, so I might actually survive. The 
temperature might be a bit of a problem, however.
    If there is no objection, all additional opening statements 
submitted by the Subcommittee Members will be added to the 
record. Without objection, so ordered.
    [The prepared statement of Mr. Smith follows:]
            Prepared Statement of Representative Nick Smith
    I want to thank Chairman Ehlers and Ranking Member Udall for 
holding this hearing on the science of mercury emissions. And I would 
like to thank our witnesses for sharing their opinions with us today.
    As a farmer, I understand that we are caretakers of the land. 
Farmers understand that what they put in the land can come out in our 
food and water. If we are not careful with the land we can do 
significant damage to its productive capacity, our environment, and 
animal and human health. Therefore, we must use responsible practices 
to maintain or improve the quality of our environment.
    While farmers have learned much from thousands of years of 
tradition, modern science has revolutionized our understanding of 
agriculture. When we consider the impact of pollutants, such as 
mercury, science must be our guide in understanding the costs and 
benefits. This requires rigorous research, understanding where 
pollutants come from, where they go, what they do when they get there, 
and how they affect the land, animals and people.
    We must be caretakers of our environment so that our children and 
grandchildren can enjoy and use it as much as we have. I applaud the 
Chairman and Ranking Member for guaranteeing that science is used in 
making these decisions.

    Chairman Ehlers. At this time, I would like to introduce 
our witnesses. And we are fortunate to have an outstanding 
group of witnesses before us, broadly representative of the 
scientific and technical knowledge. I might mention we do not 
have anyone specifically from the environmental community. That 
will be dealt with at some other time, but we wanted to try and 
get the science and technology out first.
    First of all, we have Dr. Thomas Burke, who is a Professor 
and Associate Chair of the Department of Health Policy and 
Management at the Johns Hopkins University Bloomberg School of 
Public Health. Dr. Burke served as a member of the National 
Academy of Sciences Committee on the toxicological effects of 
methylmercury. Second, we have Dr. David Krabbenhoft. He is a 
research hydrologist for the United States Geological Survey, 
better known by its acronym, USGS. I had a son who spent one 
summer working for the USGS. Next, we have Dr. George Offen. He 
is the Senior Technical Leader of the Air Emission and 
Byproduct Management at the Electric Power Research Institute, 
which is the research arm of the utility industry, better known 
by its acronym, EPRI. And finally, Mr. Ken Colburn is the 
Executive Director of the Northeast States for Coordinated Air 
Use Management, an association of Northeast State Air 
Directors. As a Midwesterner, I can assure you that there is 
plenty of air in the Northeast. Previously, he served as New 
Hampshire's Air Director.
    As our witnesses presumably have been informed, spoken 
testimony is limited to five minutes each. And in case you are 
not familiar with our system, we have the little timers, one 
here and one on your table. It will glow green for talk for the 
first four minutes, yellow for sum up for the next minute, and 
red for the stop sign. And so I ask for you to observe the stop 
signs. We may give traffic citations if you don't.
    With that, after you have finished your testimony, Members 
of the Committee will each have five minutes to ask questions. 
And if there are a lot of questions, we may go an additional 
round.
    We will start with Dr. Burke. Dr. Burke, you are 
recognized.

   STATEMENT OF DR. THOMAS A. BURKE, PROFESSOR AND ASSOCIATE 
   CHAIR, DEPARTMENT OF HEALTH POLICY AND MANAGEMENT, JOHNS 
     HOPKINS UNIVERSITY, BLOOMBERG SCHOOL OF PUBLIC HEALTH

    Dr. Burke. I appreciate the opportunity to speak with you 
today. I am Tom Burke. I am a professor at the Johns Hopkins 
School of Public Health. I am epidemiologist and risk assessor, 
and I am also the Principal Investigator of the CDC Center for 
Excellence in Environmental Public Health Tracking, and I am 
currently working with about 20 states and major municipalities 
on issues of environmental exposure and public health outcomes. 
And I must say that mercury exposure and potential health 
impacts are a very important priority for the States. I am also 
a member of the National Academy of Sciences Board on 
Environmental Studies and Toxicology, and I currently co-chair 
the EPA National Pollution Prevention and Toxics Advisory 
Committee. Perhaps most importantly for today's meeting, I was 
a member of the--as you mentioned, the NAS panel that took a 
look at the toxicological effects of Methylmercury.
    Before joining Hopkins, I served as a regulator and a 
health official. I was Deputy Commissioner of Health for the 
State of New Jersey and also Director of Science for the New 
Jersey DEP, so I participated firsthand in fishing advisories 
and some very difficult policy decisions.
    My testimony today will focus on the questions that you 
have given to me.
    First I wanted to give a very quick overview of what the 
Academy Panel found in our evaluation of the scientific basis 
for the EPA reference dose, which is really the starting point 
for the regulatory actions.
    The charge to the Committee was to evaluate the scientific 
evidence, and we looked at a broad range of the available 
information, both from animal studies and from human studies, 
and really focused down on three major epidemiological studies. 
We met with the investigators to understand their methods and 
results and looked at and identified from this the most 
important, critical public health effects. We were concerned 
that mercury exposure effects different sub-populations 
differently and focused, to be most protective of public 
health, on the most vulnerable sub-population: unborn children. 
Therefore, we selected neurodevelopmental deficits as the most 
important, well-documented health effect.
    The three studies we looked at, one in the Faroe Islands, 
one in New Zealand, and one in the Seychelles, were 
epidemiologic studies of maternal exposure and neurological 
development--maternal exposure to mercury and neurological 
development in children. Now two of these studies were 
positive, and the Seychelles study, at that time, did not show 
an association.
    Based upon the public health principle of using a public 
health approach, we decided to use a positive study (they were 
all very well conducted) as the basis for our recommendations 
to EPA, the scientific basis for moving forward. We also 
conducted an analysis of population exposure here in the U.S. 
Now the large majority of Americans are at low-risk of adverse 
effects from mercury exposure, but as you mentioned, there is 
an important sub-population, high consumers of fish, that may, 
in fact, be at levels of concern. And we estimated that based 
upon women of child-bearing age and consumption patterns, there 
may be as many as 60,000 children born each year, not with 
adverse effects, but at elevated risk because of their mother's 
exposure.
    Now a major question right now, particularly in light of 
the release of a new revision or an update of the Seychelles 
study, is--is the scientific basis for the National Academy of 
Science's conclusions--has that changed? We released our report 
in July of 2000, and since that time, there have been a number 
of new studies. Perhaps the most important is this longitudinal 
update on the Seychelles Island study, which continued to 
observe the children to age 9. The new study or the new update 
is, in fact, not a new study but a continued evaluation. And it 
must be recognized that it doesn't represent a new study but 
rather a refinement of ongoing surveillance.
    The question has been raised: ``If this data were 
available, would it have changed the weight of the evidence?'' 
The latest data from the Seychelles study were not available at 
the time of the NRC report; however, the Committee did consider 
the possibility that updated results might confirm the previous 
negative findings at the Seychelles. In evaluating the overall 
weight of the evidence, we still felt that, with three well 
conducted studies, it was most appropriate to select a positive 
study, the Faroe study, as the basis for public health 
protection. Therefore, I feel, and I must say that I have 
discussed this with a number of my colleagues on the Committee, 
that the new update does not change the scientific basis for 
the Committee's conclusion.
    A few other important studies you mentioned are the 
recently published result of the CDC look at exposure, where 8 
percent of women were at levels of exposure of concern, have 
also confirmed our initial assessment of that small portion of 
the population that is at risk. And I might add at the time of 
our work, we were concerned about potential implications on 
cardiovascular effects. There has been also new evidence there.
    So to conclude, I would like to kind of sum up where the 
future direction should be. The update does not change the 
fundamental conclusions of the National Academy's report. There 
have been new studies. We are constantly reducing uncertainty 
and learning more. But as of this point, we still feel that 
there is a strong public health basis for the current EPA RFD, 
that this provides a sound and justifiable foundation for our 
efforts to protect public health. That being said, there are a 
number of important research issues that need to be undertaken, 
including getting a better idea of the exposure in this 
country, of the regional differences, identifying populations 
at high risk, and particularly, understanding the sources and 
levels of mercury contamination in our food supply. Finally, we 
need to better understand the interaction of mercury with other 
pollutants that we are exposed to, such as PCBs, to really get 
a better understanding of the long-term public health 
implications.
    Thank you.
    [The prepared statement of Dr. Burke follows:]
                 Prepared Statement of Thomas A. Burke
Mr. Chairman and Members of the Subcommittee:

    I thank you for the opportunity to testify today concerning the 
public health effects of mercury exposure. I am Dr. Thomas Burke, 
Professor and Associate Chair of the Department of Health Policy and 
Management at the Johns Hopkins Bloomberg School of Public Health, and 
I am founding Co-Director of the Hopkins Risk Sciences and Public 
Policy Institute. I am an epidemiologist and risk assessor and my major 
research interests focus on understanding and preventing the public 
health impacts of environmental exposures. I am also the Principal 
Investigator for the CDC Center of Excellence in Environmental Public 
Health Tracking at Johns Hopkins and am working with 20 states and 
major cities to improve our capacity to track hazards, exposures, and 
health effects that may be related to the environment. I am also a 
member of the National Academy of Sciences Board on Environmental 
Studies and Toxicology and serve as Co-Chair of the U.S. EPA National 
Pollution Prevention and Toxics Advisory Committee. Perhaps most 
relevant to today's hearing I served as a member of the National 
Research Council Committee on the Toxicological Effects of 
Methylmercury.
    Prior to joining the faculty of Johns Hopkins I served as Deputy 
Commissioner of Health for the State of New Jersey and Director of 
Science and Research for the New Jersey Department of Environmental 
Protection. As a State official I was directly involved in the public 
policy decisions to protect the environment and public health, 
including many fish consumption advisories. I have a first hand 
appreciation for the difficult interface of science and policy in 
developing practical and protective approaches to public health and 
environmental regulation.
    My testimony today will focus upon the questions that the 
Subcommittee has asked me to address.

What did the National Research Council panel find about the 
relationship between low-dose mercury exposure and adverse human health 
effects? Are subpopulations differentially affected by mercury 
exposure?

    In response to a request from the Congress, the NRC established the 
Committee on the Health Effects of Methylmercury to evaluate the body 
of evidence that led to the EPA reference dose RfD (1). The charge also 
included evaluating newly available data that may not have been 
considered by the Agency, and consideration of sensitive subpopulations 
that may be impacted by consumption of contaminated fish. The Committee 
conducted and extensive review and weight of evidence evaluation of the 
available published literature on the health effects of mercury from 
both animal and human studies, and met with the investigators of major 
epidemiological studies to examine their methods and findings. Mercury 
exposure can cause a wide range of adverse effects throughout the life 
span and there are extensive data on effects on the developing brain.
    Subpopulations may be differentially affected by mercury exposure. 
Therefore, to be protective of public health, the Committee focused 
upon the most vulnerable subpopulation, unborn children. We selected 
neurodevelopmental deficits as the most sensitive well documented 
effect, the critical effect for the derivation of an RfD.
    The Committee carefully evaluated three large well designed 
epidemiological studies of the relationship between prenatal 
methylmercury exposure from maternal consumption of fish and subsequent 
neurodevelopmental deficits. In the Faroe Islands (2) and New Zealand 
(3) studies mercury exposure was associated with adverse 
neurodevelopmental outcomes. In the Seychelles (4) no relationship with 
adverse outcomes was observed. After considering the results of the 
three studies and the weight of the evidence the Committee concluded 
that a positive study provides the strongest public health basis for 
the development of public health and regulatory exposure guidance. The 
Faroe Island study was recommended as the critical study for the 
development of the RfD. Based upon the benchmark dose derived from this 
study, the Committee concluded that the EPA RfD of .1ug/kg per day is 
scientifically justifiable.
    The Committee also conducted an analysis of population exposure 
levels and found that the large majority of Americans are at low risk 
of adverse effects, but some high fish consumers may be at risk of high 
mercury exposure. Based upon available fish consumption surveys for 
woman of childbearing age it was estimated that 60,000 children may be 
born each year with an elevated risk of adverse neurodevelopmental 
effects due to maternal mercury exposure.

To what extent have studies published since the panel issued its report 
in 2000 altered our knowledge about the health effects of mercury?

    The NRC report was released in July of 2000. Since that time there 
have been a number of studies that have made important contributions to 
the body of knowledge concerning the public health impacts of mercury 
exposure. Perhaps the most notable is the recent longitudinal update of 
the Seychelles Island study (5) which reports on the continued 
observation of the cohort to 9 years of age. The results of the update 
reaffirm the earlier findings of no significant adverse neurological 
effects related to of in utero mercury exposure. The update provides 
important information on the Seychelles cohort as the children grow 
older. However it must be recognized that the findings do not represent 
a ``new'' study, but rather provide a refinement of the ongoing 
surveillance.
    The question has been raised ``If the Seychelles update were 
available to the NRC Committee would the recommendations have been 
different?'' The latest data from the Seychelles study were not 
available at the time of the NRC report; however the Committee did 
consider the possibility that updated results might confirm previous 
negative findings. In evaluating the overall weight of the evidence of 
three well conducted studies, two positive and one negative, it was 
deemed appropriate to select a positive study as the basis for public 
health protection. I therefore feel that the recent report adds to our 
knowledge, but does not change the scientific basis for the Committee's 
conclusions.
    Other studies that have been published since the release of the NRC 
report have confirmed some of the findings and concerns of the 
Committee. CDC's National Health and Nutrition Examination Survey found 
that eight percent of women of child bearing age had blood mercury 
levels that indicate exposures above the current RfD (6). This confirms 
the findings of the Committee's margin of exposure analysis that found 
there is a small but important percentage of the population with 
exposures in the range of public health concern. In addition, a recent 
epidemiological study has found an association between mercury exposure 
(measured by toenail mercury concentration) and myocardial infarction 
(7). The need to better understand potential links between mercury 
exposure and cardiovascular disease and hypertension was among the 
research recommendations of the Committee.

What are the future research needs with respect to understanding the 
health effects of mercury?

    There are a number of important continuing research needs if we are 
to improve our understanding of the public health impacts of mercury 
exposures in the U.S. population. The most fundamental need is to 
measure actual exposure levels in the population to identify those at 
highest risk, examine geographic differences, and improve our 
epidemiological surveillance to identify and prevent any related 
adverse health outcomes. Since there are fish consumption advisories 
throughout virtually all regions of the country, state health and 
environmental officials need improved tools to evaluate exposure and 
provide the public with better information about preventing exposures 
and health risks. Surveillance of mercury sources, exposures, and 
possible health related outcomes should be included in the developing 
CDC National Environmental Public Health Tracking Network. Tracking can 
provide a foundation for U.S. based epidemiological investigations, 
guide the development of more effective regulatory strategies and 
enable us to measure our progress.
    Better tracking of the mercury concentrations in fish and 
throughout the food supply is also needed. This will improve both our 
assessment and communication of mercury risks. Currently available 
information on important food sources is extremely limited. Consumers 
have little information resulting in enormous confusion and limiting 
the effectiveness of risk communication and prevention efforts.
    Research is also needed to understand the potential impacts of 
mercury exposure throughout the life span. Little is known about 
possible long-term effects of exposure. This research should include 
examination of possible cardiovascular, reproductive, neurological, 
immunological and carcinogenic effects.
    Research should also include evaluation of the health implications 
of interaction of mercury with other pollutants. For example, what are 
the health implications of cumulative exposures to mercury and 
persistent organic pollutants from dietary exposure? How do concurrent 
exposures to PCBs and other potential neurotoxic pollutants impact 
potential population health risks?
    In conclusion, mercury is one of the most well studied 
environmental pollutants. Its potential harmful effects have been well 
documented in both human and animal studies. There is tremendous public 
concern about the potential adverse health effects of mercury, 
particularly regard the health and development of children. New studies 
have contributed important new insights, yet there remain a number of 
unanswered questions particularly concerning the full range of public 
health impacts from long-term low-level exposures. In the long-term the 
reduction of population exposures and management of mercury risks will 
depend upon our ability to recognize and reduce mercury emissions. In 
the meantime the current EPA RfD provides a sound and justifiable 
foundation for our efforts to protect the public's health.
    Thank you very much for this opportunity to address the 
Subcommittee.

References

        1. LNational Research Council. 2000. Toxicological Effects of 
        Methylmercury. National Academy Press, Washington, D.C. 344 p.

        2. LGrandjean, P. et al. 1997. Cognitive deficit in 7-year-old 
        children with prenatal exposure to methyl mercury, 
        Neurotoxicol. Tertol 19:417-428.

        3. LCrump, K.S., Kjellstrom, T., Shipp, A.M., Silvers, A., 
        Stewart, A. Influence of prenatal mercury exposure upon 
        scholastic and psychological test performance: benchmark 
        analysis of a New Zealand cohort. Risk Anal. 1998 Dec., 
        18(6):701-713.

        4. LDavidson, P.W., Myers, G.J., et al. 1998. Effects of 
        prenatal and postnatal methyl mercury exposure from fish 
        consumption on neurodevelopment: Outcomes at 66 months of age 
        in the Seychelles Child Development Study, J. Am. Med. Assoc. 
        280:701-707.

        5. LMyers, G.J., et al. 2003. Prenatal methylmercury exposure 
        from ocean fish consumption in the Seychelles child development 
        study. The Lancet 361:1686-1668.

        6. LSchober, S.E., Sinks, T.H., Jones, R.L., Bolger, P.M., 
        McDowell, M., Osterloh, J., Garrett, E.S., Canady, R.A., 
        Dillon, C.F., Sun, Y., Joseph, C.B., Mahaffey, K.R. 2003. Blood 
        mercury levels in U.S. children and women of childbearing age, 
        1999-2000. JAMA 2, 289(13):1667-1674.

        7. LGuallar, E., Sanz-Gallardo, M.I., van't Veer, P., Bode, P., 
        Aro, A., Gomez-Aracena, J., Kark, J.D., Riemersma, R.A., 
        Martin-Moreno, J.M., Kok, F.J. 2002. Mercury, fish oils, and 
        the risk of myocardial infarction. N. Engl. J. Med., 
        347(22):1747-1754.

    Chairman Ehlers. Thank you.
    Dr. Krabbenhoft.

  STATEMENT OF DR. DAVID P. KRABBENHOFT, RESEARCH SCIENTIST, 
                UNITED STATES GEOLOGICAL SURVEY

    Dr. Krabbenhoft. Mr. Chairman and Members of the 
Subcommittee, thank you for this opportunity to present, on 
behalf of the U.S. Geological Survey, this statement regarding 
``Mercury Emissions: State of the Science and Technology.''
    Although humans have been using mercury in a variety of 
ways for the past 2,000 years, mercury has been cycling in the 
environment for a much longer period of time. Over the past 100 
years, however, human activities related to industrialization 
and modernization have increased the amount of mercury cycling 
the environment and subsequent deposition to the landscape by a 
factor of about three to five over pre-industrial times.
    The conversion process of inorganic mercury, which 
comprises the vast majority of mercury in the atmosphere, to 
methylmercury, known as methylation, has an overwhelming 
importance on the exposure of humans and wildlife and the 
environment. Were it not for methylation, bioaccumulation of 
mercury in the environment would only happen under extremely 
rare circumstances.
    My testimony today seeks to describe a general 
understanding of the current state of science regarding mercury 
transport fate in the environment. While constructing this 
testimony, I have focused on the four questions your 
Subcommittee has asked of me.
    Question one: ``What do we know about how mercury reacts in 
the atmosphere and what determines its deposition, and to what 
extent is deposition local, regional, or global?'' The amount 
of mercury contributed from each of these geographic source 
types at any particular location can range widely. In truly 
remote settings where equally high levels of mercury in food 
webs can occur, contributions from global mercury sources 
likely dominate, whereas in settings near emission sources, the 
local contributions are likely more important.
    One critical scientific advance of researchers over the 
past decade has been the ability to discriminate the three 
principle forms of mercury in the atmosphere, and those are: 
reactive gaseous mercury; gaseous elemental mercury; and 
particulate mercury. Although greater than 95 percent of the 
mercury in the atmosphere is gaseous elemental mercury, what 
deposits onto the landscape are the other two forms of mercury. 
As such, understanding the processes that regulate the 
transformation of these forms of mercury is critical for being 
able to predict where mercury from a particular source will 
deposit.
    Question two: ``What do we know about the relative 
reactivity of old versus new mercury and anthropogenic versus 
natural mercury?'' Mercury is an element, and as such, all 
mercury is ``natural.'' However, its reactivity and mobility is 
controlled by the details of its chemical form, and several of 
man's activities serve to change its chemical form. For 
example, mercury in coal is largely found as traces in the 
mineral pyrite, which is relatively stable if left undisturbed. 
However, upon combustion, much of the mercury in the coal is 
reduced to the gaseous elemental mercury state, thereby 
increasing its post-emission transport distance and reactivity.
    Recently, researchers have begun to address the question of 
old versus new mercury in the environment. The terms ``new'' 
and ``old'' do not refer to sources, but rather how long that 
mercury has been in the environment. Results thus far have 
clearly shown that experimentally administered new mercury is 
much more apt to become methylated and incorporated into the 
food web than old mercury probably because of physical and 
chemical differences in these two mercury pools.
    Question three: ``What does research tell us about the 
extent to which reducing mercury emission deposition will 
reduce mercury levels in fish?'' Past studies at point source 
contaminated sites in areas where atmospheric deposition has 
declined tell us that fish mercury levels generally follow 
mercury-loading rates. The timing in the recovery, however, can 
vary substantially from years to decades. The extent of the 
recovery will likely be proportional to the fraction of the 
deposition rate at any specific location that is eliminated.
    Lastly, question four: ``What are the future research needs 
with respect to understanding how mercury cycles in the 
environment?'' First, research to improve our understanding of 
chemical forms of mercury from emission sources, changes that 
occur after release and during transport, and controls on 
deposition patterns. Second, research to help refined estimates 
of the relative contributions of both natural and anthropogenic 
mercury emissions. Third, research to improve our understanding 
of what factors control the far-ranging observed differences 
among ecosystem types in terms of their sensitivity to mercury 
loading and what non-source control strategies can man consider 
to reduce methylmercury production and exposure. Lastly, 
research to help develop an understanding of the mercury 
sources and sites of methylation that are responsible for high 
levels of mercury in marine food webs. The vast majority of 
mercury research over the past 15 years has been done on 
freshwater ecosystems, but few insights can be transferred from 
those freshwater systems to the marine environment from which 
most consumed fish are harvested.
    Mr. Chairman, this concludes my remarks, and I would be 
happy to respond to questions by Members of the Subcommittee.
    [The prepared statement of Dr. Krabbenhoft follows:]
               Prepared Statement of David P. Krabbenhoft
    Mr. Chairman and Members of the Subcommittee, thank you for this 
opportunity to present, on behalf of the U.S. Geological Survey, this 
statement regarding ``Mercury Emissions: State of the Science and 
Technology.'' This statement seeks to describe a general understanding 
of the current state of science regarding mercury transport and fate in 
the environment, focusing on the four questions posed by the 
Subcommittee.

Background

    Although humans have been using mercury in a variety of 
applications for more than 2000 years, mercury has been cycling in the 
environment for a much longer time through natural occurrences such as 
volcano eruptions. Over about the past 100 years, however, human 
activities related to industrialization and modernization have 
increased substantially the amount of mercury released to the 
environment, particularly via atmospheric emissions. Most researchers 
have concluded that rates of atmospheric deposition of mercury on 
average are about 3-5 times greater presently than in historic times. 
Once deposited on oceans, land or freshwater systems, a portion of the 
mercury re-emits back to the atmosphere. As a result of the mercury re-
emission process, fluxes from land and oceans to the atmosphere are now 
about three times higher than pre-industrial periods, and mercury 
contributions from these ``natural sources'' constitute about two 
thirds of the mercury emissions presently. Although these re-emissions 
come via ``natural sources,'' the increased amount of mercury cycling 
in the environment is driven by the increased amount of mercury 
introduced from human sources.
    The overall increase in the amount of mercury cycling in the 
environment has resulted in exacerbated mercury exposure to food webs, 
including humans, and the widespread awareness of these levels has led 
to consumption advisories for elevated levels of mercury in fish. 
Concerns about environmental mercury pollution and contamination of 
aquatic food webs stem largely from the human health risks of dietary 
exposure to methylmercury, the dominant form of mercury in the edible 
flesh of fish and aquatic mammals, and the form of mercury that is the 
focus of most environmental studies today.
    The widespread geographic extent and adverse consequences of 
methylmercury pollution continue to prompt considerable scientific 
investigation. The conversion of inorganic mercury, the form comprising 
the vast majority of mercury in the atmosphere, to methylmercury 
(methylation) results from a series of very complex, processes that are 
facilitated by naturally occurring bacteria. Scientists now understand 
that the methylation process primarily occurs in anaerobic (oxygen 
free) sediments in aquatic ecosystems. In addition, we know that the 
methylation process involves the intersection of the environmental 
sulfur cycle with the environmental mercury cycle. The end result of 
these complex processes is a net increase in the overall toxicity of 
mercury, such that if mercury were not methylated in the environment, 
it likely would only reach levels of toxicological concern in rare 
instances.

1. LWhat do we know about how mercury reacts in the atmosphere and what 
determines its deposition? To what extent is deposition local, regional 
or global?

    Although there is general agreement that atmospheric mercury 
emissions and transport pathways are the phenomenon that are chiefly 
responsible for the widespread mercury contamination, particularly for 
remote and semi-remote areas, scientific understanding of the processes 
controlling the region of influence of a specific emission source is 
still an active area for research. Establishing the region of influence 
for various mercury emission sources has been evaluated through several 
means, including: intensive site-specific monitoring, numerical 
modeling, and historical reconstruction of anthropogenic effects 
through dated cores of sediment and ice. Together, all these scientific 
approaches have yielded considerable improved understanding of the 
relationships between atmospheric mercury sources and deposition areas, 
but it should be stressed that this is still an area of evolving 
understanding.
    One of the critical scientific advances of researchers over the 
past decade has been the ability to discriminate the three principal 
forms of mercury that exist in the atmosphere:

         particulate mercury associated with settling 
        particles,

         reactive gaseous mercury (RGM), and

         gaseous elemental mercury.

    These three forms largely are determined by the chemical species 
(speciation) in which the mercury exists, that is, whether it is in a 
neutral, uncharged state as in gaseous elemental mercury, or in a 
charged state. Mercury in the atmosphere is largely (>95 percent) 
gaseous elemental mercury, although most of what deposits is composed 
of the other two forms of mercury (particulate and RGM). Particulate 
and reactive gaseous mercury have relatively short travel distances (up 
to tens of kilometers) and small residence times in the atmosphere, 
whereas gaseous elemental mercury exhibits global-scale transport and 
has an average atmospheric residence time of about one year. As such, 
understanding what controls the transformation from gaseous elemental 
mercury to particulate or RGM, is critical for being able to predict 
where mercury will deposit from an emission source.
    Presently, scientists believe that mercury depositing in remote 
settings, at long distances from substantial sources, is derived from 
the transformation in the atmosphere of gaseous elemental mercury by 
ozone and possibly several other atmospheric oxidants. On the other 
hand, mercury deposited near emission sources is likely to be released 
as particulate mercury or RGM. Atmospheric emission sources, especially 
those related to human activities, have extremely variable amounts of 
the three forms of mercury, and as such the region of influence of a 
specific emission source can be quite variable and difficult to predict 
in the absence of source-specific measurements. Scientists have been 
able to match deposition patterns measured on the ground using mercury 
speciation measurements at a limited number of combustion sources and 
numerical models that simulate post emission oxidation reactions. This 
lends credence to many of the assumed important factors controlling 
source-receptor relationships for mercury.
    Reliable records of temporal trends in mercury deposition at a 
specific site also can be useful for evaluating mercury sources through 
time. Temporal trends in mercury deposition can be obtained by using 
dated sediment and/or glacial ice cores, where a variety of scientific 
tools are used to establish the age of various horizons in the core, 
for which a mercury concentration can be measured. Sediments from 
lakes, reservoirs, and bogs have been used in the past for historical 
reconstructions of mercury deposition. These historical reconstruction 
efforts have proven to be useful for evaluating local-to-global mercury 
sources. Scientists using this approach have successfully documented 
changes to mercury deposition from natural and human-related mercury 
emissions over thousands of years, and illustrated that mercury 
contributions at any particular location can range from local to 
global, and the source attribution can change dramatically over time.
    In remote and semi-remote areas of North America that lack local 
sources of anthropogenic mercury, the rate of mercury accumulation in 
many lake sediments has increased by a factor of 2 to 4 since the mid-
1800s or early 1900s. Dated ice cores are also a useful means to infer 
mercury deposition, albeit at high altitudes or in very remote polar 
settings. An ice core from the Fremont Glacier, Wyoming, demonstrated 
several key findings. It illustrated how variable mercury deposition 
can be at any particular location through time, and how various mercury 
sources can dominate a depositional period. For this specific location 
in Wyoming, the ice core revealed that:

        (1) Lmercury deposition rates after industrialization have 
        ranged has a high as 20 times greater than pre-industrial 
        periods;

        (2) Lat times, volcanic eruptions located in the northern and 
        southern hemisphere have resulted in recognizable, short-lived, 
        periods of high mercury deposition;

        (3) Lupwind regional uses, such as the California Gold Rush, 
        are clearly observed; and

        (4) Labout 70 percent of the mercury deposited in this location 
        over the 270 year time period recorded by the ice core is 
        attributed to global human activities.

    Ascertaining the local, regional, or global mercury source 
contributions to any particular location is difficult. At any location, 
the amount contributed from each of these three geographic source types 
could range widely. In truly remote settings, the contributions of 
mercury from globally distributed sources will likely be more 
important; whereas, in settings nearer emission sources the local 
contributions will likely predominate. Future abilities to predict the 
fractions from these sources will rely on improved understanding of 
mercury speciation at various sources, transport processes and 
reactions, and deposition processes.

2. LWhat do we know about the relative reactivity of old vs. new 
mercury and anthropogenic vs. natural mercury?

    Unlike many other high-visibility environmental pollutant problems, 
mercury is an element, and as such, all mercury originated as 
``natural'' mercury. The reactivity and mobility of mercury is 
controlled by the details of its chemical form (speciation) in the 
environment. It is in affecting this chemical form that man has had the 
greatest impact. For example, the principal ore of mercury is the 
mineral Cinnabar, which is relatively insoluble and stable, and was 
used as a red pigment long before the process for refining mercury ore 
to recover elemental mercury was discovered. Converting cinnabar to 
liquid elemental mercury, which was the specific conversion process of 
placer miners during the Gold Rush, greatly increases its propensity to 
vaporize to the atmosphere. Similarly, most of the mercury found in 
coal deposits is found as traces in the mineral pyrite, which is also 
relatively stable if left undisturbed. However, upon combustion a 
substantial amount of the mercury in coal is converted to gaseous 
elemental mercury, and thereby increasing its post emission transport 
distance.
    There are important natural processes that also serve to increase 
the reactivity of mercury, regardless of whether it originates from 
natural or anthropogenic sources. For example, researchers recently 
discovered that natural processes lead to formation of high levels of 
bromine near the surface of the Arctic and Antarctic regions at the 
time of the first sunrise, following the extended dark, polar winter. 
This process serves to oxidize (chemically change) large quantities of 
gaseous elemental mercury in the atmosphere over the polar regions, 
thereby converting it to particulate or reactive gaseous mercury and 
substantially increasing the deposition rate of a highly reactive form 
of mercury to the landscape there. In summary, there are no known 
differences between the chemical reactivity of mercury from 
anthropogenic or natural sources, but what does matter is what controls 
or alters the chemical form of the mercury.
    Recently, researchers have begun to investigate whether there is 
any difference between ``new'' versus ``old'' mercury in the 
environment. The terms ``new'' and ``old'' do not refer to the source, 
but simply how long the mercury has been deposited on the landscape. 
This question has been posed because of vast pools of mercury that 
currently reside in soils and sediments from over a century of enhanced 
mercury deposition. Scientists wondered if this relic mercury pool 
might not sustain the present mercury problem for very long periods of 
time.
    In order to address this question, scientists have initiated dosing 
studies, in which mercury is delivered to test sites ranging in size 
from about a cubic meter, to whole watershed scale. When conducting 
these studies, scientists are using traceable forms of mercury that 
behave the same as the existing mercury, but that are distinguishable 
using advanced analytical procedures. This experimental approach has 
been applied thus far in two distinctly different ecosystems: the 
Everglades of Florida, and a boreal forest ecosystem in western 
Ontario. Results from these two studies have shown remarkable agreement 
in many ways, despite their different ecological settings. First, the 
results have clearly shown that the experimentally administered mercury 
(``new mercury'') is much more apt to become methylated (about 5 to 10 
fold) than previously existing ``old mercury.'' The precise physical 
and/or chemical reasons for these observations are still being 
researched, but at this point we do not have a definitive explanation.

3. LWhat does research tell us about the extent to which reducing 
mercury deposition will reduce mercury levels in fish?

    Recent and historic research results tell us that fish mercury 
levels generally follow changes in mercury loading rates, both for 
increasing and decreasing rates. The timing of the recovery, however, 
can vary substantially, and in some cases can take many decades. For 
example, at industrially polluted Clay Lake, Ontario, mercury 
concentrations in fish have declined from peak levels but remained 
substantially above the Canadian mercury advisory level (0.5 mg/g) 
nearly three decades after operations ceased at a nearby chlor-alkali 
plant source. Mercury concentrations in fish from Clay Lake decreased 
rapidly after the plant ceased operations--from about 15 micrograms per 
gram wet weight in 1970 to about 7.5 micrograms per gram in 1972--and 
then declined gradually to about 3.5 micrograms per gram in 1983. 
However, concentrations apparently declined little during the next 15 
years (mercury in fish tissues averaged 2.7 micrograms per gram in a 
sample of 14 walleyes taken from Clay Lake in 1997 and 1998). It should 
be noted however, that the cause of persistent problems with 
methylmercury contamination of aquatic biota at historically 
contaminated sites may result from:

         continuing, unintended emissions of mercury from the 
        local point source,

         recycling and methylation of the mercury present in 
        contaminated sediments,

         temporal increases in the reactivity of mercury from 
        highly contaminated zones,

         current atmospheric deposition of mercury from other 
        sources, or from a combination of these factors.

    More recently, researchers conducting mercury-loading studies have 
observed that there is a direct relationship between the amount of 
mercury added to an ecosystem, and the amount that is observed in fish. 
The time frame for a response depends on the ecosystem in which the 
study was conducted. In the Everglades, the response was very fast 
(within the season of the experiment or about 30-90 days). In a deeper, 
colder lake in Canada, the response was about a year, but the magnitude 
of the response there was still growing after two years. Although it 
stands to reason that the reverse observation would also be true (that 
reduced levels of loading would lead to lower levels in fish), 
researchers need more time to monitor the experimental sites when they 
transition from mercury loading studies to mercury reduction or 
recovery studies.

4. LWhat are the future research needs with respect to understanding 
how mercury cycles in the environment?

    There are several areas of research needed to reduce the 
uncertainties relating the linkages between mercury sources, cycling in 
the environment, and bioaccumulation in fish.

         Although scientists have made substantial advances in 
        our understanding of the importance of detailed information on 
        the chemical form of mercury in the environment and important 
        chemical reactions, an incomplete understanding still exits. At 
        the present time, relatively few detailed studies of 
        atmospheric mercury transport have been conducted near specific 
        sources, such as: combustion facilities, urban settings, or 
        near known natural mercury sources. Without this information, 
        it is difficult to predict how much mercury in a particular 
        location is derived from local, regional, or global sources.

         Better definition of the relative contributions of 
        natural versus anthropogenic sources. Current estimates of 
        mercury emissions from these two broadly defined source 
        categories range substantially, and presently hinder our 
        ability to anticipate the level of benefit that might be 
        derived from proposed emission reductions. Natural mercury 
        source emissions are particularly poorly understood.

         Better understanding of what factors control the 
        observed far-ranging differences among ecosystem types, in 
        terms of sensitivity to mercury loading and bioaccumulation. 
        The literature holds that some ecosystems are very sensitive to 
        mercury inputs and can yield substantial levels of 
        methylmercury, while others are not. A better understanding of 
        what controls this sensitivity to mercury inputs and production 
        of methylmercury will greatly aid our ability to predict the 
        level and timing of potential benefits received from changes to 
        mercury loads.

         At the present time, very little understanding from 
        the scientific literature can be derived for resolving where 
        marine fish get their mercury. This is particularly important 
        in light of the fact that most of the fish consumed in the 
        United States and elsewhere are marine fish, yet a 
        preponderance of the literature is based on freshwater studies. 
        It is difficult to use the conceptual models developed for 
        shallow, freshwater systems and apply them to deep, oceanic 
        settings. Integrated, multi-disciplinary studies that link 
        terrestrial mercury sources, near-coastal and estuarine 
        cycling, and bioaccumulation of mercury in important commercial 
        and sport fish are needed.

         Lastly, questions that require additional attention 
        to ensure effective environmental protection are: how and to 
        what extent will decreases in anthropogenic mercury emissions 
        decrease the amount of mercury cycling in the environment, in 
        what magnitude will those decreases reduce mercury 
        bioaccumulation in aquatic ecosystems, and what will be the 
        timing of such a recovery.

    Mr. Chairman, this concludes my remarks. I would be happy to 
respond to questions Members of the Subcommittee may have.

    Chairman Ehlers. Thank you.
    Dr. Offen.

STATEMENT OF DR. GEORGE R. OFFEN, SENIOR TECHNICAL LEADER, AIR 
  EMISSION AND BYPRODUCT MANAGEMENT, ELECTRIC POWER RESEARCH 
                           INSTITUTE

    Dr. Offen. Thank you, Chairman Ehlers, for the opportunity 
to speak before you on the important subject of mercury 
control. You have kindly introduced EPRI so I don't need to do 
that except to mention that we do, in our work, collaborate 
quite a bit with suppliers, equipment suppliers, and government 
agencies. And particularly in the case of mercury, we have 
strong collaborations with the Department of Energy and the 
EPA.
    In that area, you asked us to talk about five questions in 
three areas. The first one is on existing controls and what 
mercury reductions can one expect from those controls. On the 
average in the U.S., current power plants with their emission 
controls for particulates, NOX, and SO2 are 
achieving a 40 percent reduction. However, that varies from 10 
percent at some power plants to 90 percent at other power 
plants. And we see the primary differences being a function of 
the coal that is burned and the air pollution controls that are 
already in place at those power plants. Furthermore, those 
numbers are actually what we call snapshots in time. They are 
derived from three tests taken for two-hour periods, and we do 
know that mercury emissions vary widely over time. Over a 
week's period, they can vary by a factor of five to one, even 
when the same coal is burned.
    There is, beyond the 40 percent number I mentioned, a 
fraction of the coal, particularly a portion of the eastern 
bituminous coal, that is washed, and the washing process is 
used for removing ash and sulfur. And that process also does 
remove some mercury, on the average 25 to 35 percent.
    You asked what determines the effectiveness of the mercury 
reductions, and I have, more or less, answered that. The coal, 
and especially the chlorine content and its reactivity, its 
ability to burn completely, and, of course, the air pollution 
control devices. And the reason these two relate is that 
mercury, as Dr. Krabbenhoft mentioned, is released in two 
different gaseous forms. Any mercury that is particulate is 
captured by the particulate control. But it can be, as he said, 
either an elemental mercury or an oxidized form when it is 
combined with other chemicals. And the other pollution 
controls, like particulate and SO2 controls, really 
capture the oxidized fraction and not the elemental fraction.
    You asked about controls that are under development today. 
The industry, and that includes EPRI, the suppliers, the power 
industry themselves, DOE, EPA, are really following four 
parallel paths on that. One is to try to better understand the 
interactions between selective catalytic reduction for NOX 
control and scrubbers for SO2 control with regard to 
the mercury impact, what is called the co-benefits in all of 
the discussions that you have had. We see it in some cases and 
don't see it in some cases.
    The next area is the area of sorbent injection, which is 
the technology where you blow a dust, a material like activated 
carbon, into the gas and that absorbs the mercury, and then the 
activated carbon with the mercury is captured by the 
particulate control. We are doing quite a bit of work in that 
area as industry. That seems to be the nearest-term mercury-
specific control that is on people's agenda. We are trying to 
reduce the costs. We are trying to develop sorbents that are 
more effective for more different coals. The--and also trying 
to understand what the negative impacts may be and mitigating 
those and overcoming those.
    The third area is to develop and demonstrate new 
technologies. These are falling into a couple of categories. 
One, again, is to help capture mercury and scrubbers, so we are 
looking at catalysts that will make more oxidized mercury. We 
are looking at chemical addition to boilers that will make more 
oxidized mercury. And the other is trying materials that you 
can put in the very back end of your power plant that sit there 
and that capture mercury and that you occasionally regenerate, 
pull out and regenerate.
    And then finally, we are looking at multi-pollutant 
controls and seeing what role they could play in the picture of 
mercury.
    You asked about the inferences of the full-scale tests of 
these controls on what we know about effectiveness and cost. I 
need to mention that the only full-scale tests that have been 
done today have been short-term, about one week. Each test has 
been on a different fuel. And you have a figure in your package 
that shows the removal is a function of the amount of carbon 
that is injected. And you will see a separate line for each 
test that has been done. Again, one test for each fuel. We 
don't know if those lines are representative of each of those 
fuels or whether they are unique situations. They are also 
short-term, so we don't have any sense of what the long-term 
impact might be.
    Fortunately, this is where the DOE is stepping up to the 
plate right now. They have just released eight contracts that 
will be testing all of these technologies or many of these 
technologies for multiple month periods, one- or two-month 
periods, so we should have a better handle on that after the 
tests are done. That will be in the '04, '05, and possibly '06 
time frame.
    With that said, just to give you a flavor of the numbers, 
we are seeing right now on these, with the caveats, 60 to 70 
percent capture with sorbent injection in plants firing Powder 
River Basin coal, which is now used by about 40 percent of the 
plants, and going up to 90 percent in the low-sulfur eastern 
bituminous case, which is the one case we are getting that much 
reduction. As I mentioned, we don't understand the 
sustainability and long-term impacts of that. So we are very 
much looking forward to and very supportive of the DOE program 
to extend our tests and our knowledge on that base.
    Thank you, Mr. Chairman.
    [The prepared statement of Dr. Offen follows:]
                 Prepared Statement of George R. Offen
Mr. Chairman and Members of the Subcommittee:

    Thank you for inviting EPRI to address the House Committee on 
Science's Subcommittee on Environment, Technology, and Standards on the 
important subject of mercury reductions from power plants. I am George 
Offen, and I manage our programs in air emission reductions and the 
beneficial use of combustion products. EPRI was established 30 years 
ago as a non-profit, collaborative R&D organization to carry out 
electricity-related supply, delivery, end-use, and environmental R&D in 
the public interest. Our funders include electric power companies 
responsible for over 90 percent of the electricity sold in the U.S., as 
well as over 60 companies worldwide. We also cooperate closely with 
(and for some projects receive funding from) government agencies in our 
research programs, particularly DOE and EPA, as well as equipment 
suppliers and engineering firms. This is especially true in the case of 
mercury.
    For well over a decade, EPRI has been conducting research on all 
aspects of mercury sources, movement and chemical transformation in the 
environment, health effects, and methods to reduce emissions. My 
remarks today will respond to five questions in three topical areas 
that this subcommittee asked EPRI to address on the subject of mercury 
control technologies.

1. Existing controls

A. LTo what extent do control technologies in use today at utilities 
        reduce mercury pollution?

    On average across the domestic coal-fired population of power 
plants, current technologies used to reduce particulate, NOX and 
SO2 emissions capture about 40 percent of the mercury that 
enters these boilers with the coal. However, these removals vary from 
less than 10 percent to over 90 percent, depending on the coal and air 
pollution controls used. Further, the data that underlie these 
generalizations are snapshots in time at each plant in many cases just 
a few tests over a 1-2 day period--while we now know that emissions can 
vary by a factor of five or more over a week's period. I should note 
that the removal efficiencies cited above are additive to the mercury 
removed by coal washing for the many supplies of eastern bituminous 
coal that are washed; cleaning these coals often provides an average 
mercury reduction of 25-35 percent before the coal arrives at the power 
plant.

B. LWhat determines the effectiveness of these technologies in reducing 
        mercury emissions?

    The primary factors that affect the capture of mercury by existing 
air pollution controls are the coal burned and the type of air 
pollution (NOX, SO2, particulate) controls used at the 
plant. Mercury in the flue gas appears as a mix of elemental (or 
metallic, non-water soluble) and oxidized (water soluble) mercury, 
depending primarily on the coal and to a lesser extent on the design of 
the boiler. Some controls, such as scrubbers for SO2 
reduction, capture only oxidized mercury. In some cases, selective 
catalytic reduction (SCR) for NOX control may increase the percent of 
the mercury that is in the oxidized form, enabling a downstream 
scrubber (if present at the power plant) to capture more of the 
mercury. Coals and boilers that result in increased levels of carbon 
leaving the boiler unburned tend to produce a fly ash that may adsorb 
some of the mercury. The amount that would be adsorbed and subsequently 
captured by the particulate control depends on the technology used--
electrostatic precipitators or baghouses--due to the difference in how 
the fly ash and flue gases contact each other in these devices. All 
these interactions depend on complex chemical reactions between various 
species in the flue gas, especially chlorine, but we do not yet totally 
understand this chemistry.

2. New controls

A. LWhat are the major technologies under development today to control 
        mercury emissions from power plants?

    The technical community is following four parallel paths to seek 
cost-effective, sustainable mercury controls for the domestic boiler 
population--(1) trying to understand and improve the performance of 
existing controls, especially the combination of SCR and scrubbers; (2) 
developing and lowering the cost of sorbent injection (such as 
activated carbon), the nearest-term mercury-specific technology; (3) 
developing and demonstrating new technologies; and (4) developing 
multi-pollutant controls to capture NOX, SO2, mercury, and 
particulate in an integrated fashion. With sorbent injection, a powder 
such as activated carbon is injected into the flue gas ahead of the 
particulate collector, where it captures the mercury by adsorption and 
is then, itself, collected along with the fly ash in the particulate 
collector. The technical community is looking at variants of this 
process aimed at reducing costs, avoiding contamination of the ash by 
using non-carbon sorbents, and developing sorbents that work for all 
coals and particulate/SO2 controls. New technologies include 
catalysts designed specifically to oxidize mercury that would be placed 
at the clean end of the particulate collector for plants with 
downstream SO2 control; attempts to make flue gas from 
Powder River Basin and other low-chlorine western coals behave like 
Eastern bituminous coal by adding chemicals to the coal or boiler; and 
fixed structures that sit in the flue gas ducts and adsorb mercury 
until they need to be regenerated.

B. LWhat do full-scale demonstrations tell us about the likely costs 
        and effectiveness of these technologies?

    To date we only have full-scale data on activated carbon injection, 
and those data are limited to one week tests at just one site for each 
of the coals tested. Mercury removals were different at each of the 
sites (see Figure, which also shows the broad range of pilot-scale 
results), and we do not know if this was due to the different fuels or 
other reasons. The short-term removals ranged from a maximum of 60-70 
percent at the site burning Powder River Basin coal to as much as 90 
percent at the plant firing Eastern low-sulfur bituminous coal site. 
Because these tests were demonstrations, we do not have commercial cost 
data for the installations. Furthermore, having no long-term 
operational experience with these systems, we know neither their 
ability to sustain these levels of performance nor their potential 
impacts on plant operations and maintenance. Assuming sustainable 
operation and no unexpected impacts--both big assumptions at this point 
in time--we have estimated costs of $2 MWh to $3 MWh for activated 
carbon injection, including sorbent, operation and maintenance, and 
amortized capital.

3. LWhat are the major barriers to development of technologies to 
                    control mercury emissions from power plants?

    The biggest barrier is the complexity of mercury chemistry in flue 
gases, and the underlying lack of fundamental data on the chemical 
reactions in this kind of environment. This prevents us from (1) 
extrapolating tests on one power plant to other plants with apparently 
similar features, and (2) carrying out most of the development of new 
technologies in the lab, where the costs should be less and turnaround 
time quicker. Consequently, most of our development work occurs via 
full-scale trials at power plants, and we need data from enough plants 
to allow us to develop correlations we can use to predict mercury 
control performance across the population of U.S. boilers. The other 
main barrier is the absence of any long-term experience with mercury 
controls to address the questions I have raised on sustainable 
operation and potential impacts on boiler operation and maintenance.
    DOE's Phase II field test program, which EPRI strongly supports, is 
an important step to address both these needs. We believe that 
additional tests, possibly of shorter duration, are still needed to 
provide greater confidence in the representativeness of the data we 
will obtain under the DOE Phase 11 program, and they are needed on an 
accelerated schedule so that the power companies can use the results to 
meet their upcoming regulatory obligations. We would also recommend 
that DOE conduct similar field test evaluations of integrated pollution 
controls for those that show promise at smaller scale.

Summary

    Over the past decade, the technical community has made substantial 
progress in understanding mercury emissions and developing mercury 
reduction options for a wide range of coals and power plant air 
pollution control configurations. Coal washing and existing emission 
controls already reduce some of the mercury emitted from coal-fired 
power plants, although this varies widely. The ability to remove 
mercury from power plant flue gas is determined largely by the coal 
properties--especially chlorine content and coal reactivity--the degree 
to which the boiler can combust the coal completely, and the controls 
in existence at each individual plant. Correspondingly, suppliers, DOE, 
EPRI, and others are developing a variety of mercury controls to 
provide cost-effective solutions for these various fuel/equipment 
configurations. Accelerated research on mercury flue gas chemistry in 
parallel with expansion of the current DOE field test program are 
needed to determine performance and cost with confidence.
    Thank you, again, for giving EPRI the opportunity to provide these 
comments.


   STATEMENT OF MR. KENNETH A. COLBURN, EXECUTIVE DIRECTOR, 
      NORTHEAST STATES FOR COORDINATED AIR USE MANAGEMENT

    Mr. Colburn. Thank you, Mr. Chairman.
    NESCAUM appreciates the chance to address the Subcommittee 
regarding the technological feasibility of controlling mercury 
from power plants. Your timing is particularly opportune, as 
NESCAUM has just completed a major report on mercury and 
control technologies to reduce its emissions.
    Concern over the adverse health impacts of mercury has led 
the Northeast States to adopt aggressive mercury-reduction 
initiatives. In 1998, the New England States set a goal of 
reducing mercury to 50 percent by 2003, 75 percent by 2010, and 
then to virtually eliminate mercury emissions over time after 
that. We have met the 2003 goal with a reduction of 55 percent.
    We did this by conducting a careful scientific analysis of 
our mercury sources and the technological feasibility of 
controlling their emissions. This study allowed states to adopt 
standards mainly for municipal waste combustors, in most states 
the largest sources, that were almost three times more 
stringent than federal standards. Our 75 percent goal will 
require equally aggressive controls on the part of power 
plants. And several states have already moved to implement 
stringent mercury limits on power plants. Due to deposition, 
however, a strong national program through the mercury MACT is 
crucial to our ability to protect the public.
    This afternoon, I would like to comment just briefly on 
mercury controls currently in use at power plants, emerging 
mercury-specific control technologies, and barriers to 
deploying those controls all in the context of EPA's mercury 
MACT proposal.
    Under the Act, MACT can not be less stringent than the 
average achieved by the best performing 12 percent of power 
plants for which EPA has information. This is known as the 
``MACT floor.'' And based on EPA's current data, that would be 
a 91 percent reduction in mercury found in the coal. At 
present, mercury reductions from power plants are mostly co-
benefits, as Dr. Offen mentioned, resulting from controls for 
other pollutants, such as NOX and sulfur dioxide in particular.
    Nearly all coal-fired power plants have at least some air 
pollution control devices, and a number of them already achieve 
impressive mercury reductions. In EPA's tests, for example, 
four bituminous plants caught 95 percent of the mercury in the 
coal. And some subbituminous plants captured 74 to 86 percent 
of the mercury in the coal. While these co-benefits are 
substantial, they don't include any attempt to optimize the 
controls for mercury removal. Remember, they are for other 
pollutants. So the potential exists for even greater mercury 
reductions from existing controls.
    Many new mercury-specific control technologies are also 
well on their way to commercialization. Activated carbon 
injection, for example, is being successfully demonstrated in 
full-scale applications, showing that a 90 percent reduction is 
feasible for power plants at costs comparable to those for NOX 
reductions. A recent American Coal Council article, for 
example, said that activated carbon injection ``requires 
minimal new capital equipment, can be retrofit without long 
outages, and is effective on both bituminous and subbituminous 
coals,'' and thus, ``it appears unlikely that compliance with 
pending mercury reduction regulations will result in 
significant fuel switching.'' Recognizing this, a permit issued 
in June 2003 for a new power plant in Iowa burning western 
subbituminous coal requires mercury reductions of over 80 
percent using activated carbon injection.
    Other promising technologies include enhanced wet scrubbing 
to help with oxidization of the mercury, as Dr. Offen 
mentioned, K-Fuel (r), a processed coal, and Powerspan's 
Electrocatalytic Oxidation technology. I will hopefully have 
more time to go into these during the question and answer 
session.
    While these mercury-specific technologies are closest to 
commercialization, the Subcommittee should also be aware that 
several additional mercury control technologies have also 
emerged from the laboratory and are now being tested. These 
include EPRI's ``Toxicon'' process, the use of flyash as a 
sorbent at GE Power Systems and CONSOL Energy, promising 
chemical versus the usual physical sorbents at Amended 
Silicates, and various metal amalgamation approaches. The fact 
that several of these approaches were not even in existence 
when we looked at technologies two and three years ago 
illustrates the technology creation benefits that even the 
prospect of a good mercury MACT rule is having.
    The only real barrier to controlling mercury emissions from 
power plants is the current absence of a regulatory driver to 
create a market for mercury control technologies. Coal-fired 
power plants are not installing aggressive mercury-specific 
control technologies today not because they can't, but because 
there is simply no requirement for them to do so.
    In September of 2000, NESCAUM issued a report that looked 
at a history of sulfur dioxide controls, NOX controls, and auto 
emissions, and we found that regulations with well defined 
targets and compliance deadlines drive innovation and control 
technology, resulting in dramatically lower implementation 
costs than initially anticipated.
    In short, we need to expose the commercial availability 
argument for the red herring that it is. And I would caution 
the Committee that there are several other red herrings in the 
wings, those being: the technologies don't work all of the 
time, the cost is too high, and they can't be installed in 
time. We all had those with sulfur and nitrogen controls as 
well. History shows that market forces will capably address 
each of these concerns. Technology rapidly gets the kinks out 
and becomes reliable. Costs drop dramatically, and the market 
gets the job done on time. But it won't happen until there is a 
market, and there won't be a market until there is a regulatory 
driver, the mercury MACT rule.
    In conclusion, one of my favorite sayings is: ``Ask an 
engineer to do something and you get nothing but problems. Tell 
an engineer to do something and you get nothing but 
solutions.'' Today, we are getting significant mercury 
reductions as co-benefits from non-optimized controls for other 
pollutants. We have full-scale tests on new, cost-effective 
control technologies that reduce mercury substantially from a 
variety of coals. And we have new, even more promising mercury 
control technologies coming out of the labs. Let us tell our 
power sector engineers that it is time to reduce mercury 
emissions by 90 percent and begin to reap the public health and 
environmental technology benefits that the resulting market 
will bring forth.
    Thank you.
    [The prepared statement of Mr. Colburn follows:]
                Prepared Statement of Kenneth A. Colburn
    Thank you Mr. Chairman. My name is Ken Colburn. I am the Executive 
Director of the Northeast States for Coordinated Air Use Management 
(NESCAUM). NESCAUM is an association of state air pollution control 
agencies representing Connecticut, Maine, Massachusetts, New Hampshire, 
New Jersey, New York, Rhode Island and Vermont. We provide technical 
assistance and policy guidance to our member states on regional air 
pollution issues of concern to the Northeast. On behalf of our eight 
member states, I would like to express our appreciation for this 
opportunity to address the Committee regarding the technological 
feasibility of controlling mercury from electric generating facilities. 
The timing is particularly opportune, as NESCAUM has just completed a 
thorough review and assessment of mercury emissions from power plants 
and control technologies to reduce these emissions.\1\ This report, 
Mercury Emissions from Coal-Fired Power Plants: The Case for Regulatory 
Action, has been made available to the Subcommittee.
---------------------------------------------------------------------------
    \1\ NESCAUM, Mercury Emissions from Coal-Fired Power Plants: The 
Case for Regulatory Action, October 2003. See www.nescaum.org.
---------------------------------------------------------------------------
    Concern over the adverse public health impacts associated with 
exposure to methylmercury has prompted all of the Northeast states to 
issue fish consumption advisories and to adopt and implement aggressive 
mercury reduction initiatives. In 1998, the New England Governors and 
Eastern Canadian Premiers (NEG/ECP) adopted a regional Mercury Action 
Plan that established a science-based, integrated regional strategy 
intended to reduce in-region emissions by: 50 percent by 2003; 75 
percent in 2010; and virtually eliminate anthropogenic releases over 
the long-term. As of 2003, the region has achieved a 55 percent 
reduction in mercury emissions.
    The success of the NEG/ECP effort is largely a function of the fact 
that the states and provinces conducted a careful analysis of the 
sources of mercury emissions in our region and technological 
feasibility of measures available to control these emissions. For 
example, based on our technology assessment, states where able to adopt 
standards for municipal waste combustors (MWCs)--the largest source of 
mercury in many Northeast States--nearly three times more stringent 
than the federal standards, and MWCs have routinely achieved compliance 
with even the most stringent state standards. Achieving our next goal 
of a 75 percent reduction will require equally aggressive controls on 
power plants which are now the largest source of mercury emissions in 
the region. To address this need, several states in the Northeast have 
already moved to include stringent mercury emission limits as part of 
multi-pollutant requirements for power plants. However, since about 
one-third of the mercury deposition in the Northeast is attributable to 
out-of-region sources, primarily power plants, a strong national 
mercury MACT standard is critical to our ability to protect the public 
from the harmful health effects associated with exposure to 
methylmercury.
    In my testimony this afternoon, I will: (1) provide an overview of 
in-use mercury pollution control technology for power plants; (2) 
discuss emerging mercury-specific control technologies; and (3) 
consider barriers to the development and deployment of mercury emission 
controls for power plants. Given the pending proposal of a Maximum 
Achievable Control Technology (MACT) standard by the U.S. Environmental 
Protection Agency (USEPA), I will relate my comments on technological 
feasibility to that process.

In-Use ``Co-Benefit'' Mercury Control Technologies

    For existing sources, MACT cannot be less stringent than the 
average emission limitation achieved by the best performing 12 percent 
of the existing sources for which the Administrator has emissions 
information. This is known as the ``MACT floor.'' The USEPA has 
collected data from emission tests on 80 coal-fired boilers. If the 
boilers are ranked according to the percent reduction achieved, the 
average of the top 12 percent is a 91 percent reduction from the 
mercury in the combusted coal.
    At this point in time, in-use reductions from power plants accrue 
primarily as ``co-benefits'' associated with technologies designed to 
control pollutants other than mercury such as oxides of nitrogen (NOX), 
sulfur dioxide (SO2) and particulate matter (PM). All coal-
fired power plants have at least some air pollution control devices, 
such as electrostatic precipitators or baghouses (also known as fabric 
filters) for particulate control; wet or dry scrubbers for SO2 
control; and low-NOX burners, selective catalytic reduction (SCR) or 
selective non-catalytic reduction (SNCR) for NOX control. Most of these 
controls can have impacts on mercury emissions and speciation. 
Electrostatic precipitators, fabric filters and wet and dry scrubbers 
all have demonstrated particular promise in this regard.
    A number of power plants already achieve impressive mercury 
reductions with technologies that are designed to control other 
pollutants. For example, four bituminous coal-fired plants with dry 
scrubbers and fabric filters each captured more than 95 percent of the 
mercury contained in the combusted coal during emission tests. Some 
plants burning subbituminous coal that are equipped with fabric filters 
and other stack controls achieved capture of 74 to 86 percent of the 
mercury in the combusted coal during emission tests. For example: an 86 
percent mercury reduction was measured at a boiler equipped with a 
fabric filter and low NOX burner; a 74 percent mercury reduction was 
measured at a boiler using limestone injection and a fabric filter; and 
an 84 percent mercury reduction was measured at Intermountain at a 
plant which burns subbituminous and bituminous coal in a boiler 
equipped with a low NOX burner, a wet scrubber, and a fabric filter.
    As these examples illustrate, mercury co-benefits from existing air 
pollution control technologies have already proven to be quite 
substantial. Moreover, at the time of these emissions tests, there was 
no attempt to optimize controls for mercury removal. Thus, the 
potential exists to increase mercury removal significantly using 
various optimization strategies on existing controls.

Emerging Mercury-Specific Control Technologies

    Mercury-specific control technologies are well on their way to 
commercial availability. For example, activated carbon injection 
technology is being successfully demonstrated in both pilot and full-
scale applications. The results indicate that mercury control 
efficiency of over 90 percent is feasible for power plants, with costs 
that are comparable to the costs of NOX removal required under the 
federal program to achieve national ambient air quality standards for 
ozone (i.e., in the range of two mills per kilowatt hour). According to 
an article in a recent American Coal Council publication, activated 
carbon injection ``requires minimal new capital equipment, can be 
retrofit without long outages, and is effective on both bituminous and 
subbituminous coals,'' and ``it appears unlikely that compliance with 
pending mercury reduction regulations will result in significant fuel 
switching.'' \2\ Recognizing this opportunity, a permit issued in June 
2003 for a new power plant in Iowa burning western subbituminous coal 
requires mercury reductions of over 80 percent using activated carbon 
injection.
---------------------------------------------------------------------------
    \2\ Durham, Michael, Tools for Planning and Implementing Mercury 
Control Technology, American Coal Council, 2003.
---------------------------------------------------------------------------
    Other promising technologies include enhanced wet scrubbing, K-
Fuel, and Powerspan-ECOTM. Enhanced wet scrubbing technology promotes 
the oxidation of elemental mercury in the flue gas prior to entering 
the scrubber, such that as high a fraction as possible of the total 
mercury is in the oxidized state and hence more easily removed in the 
scrubber vessel. Many approaches are under development to accomplish 
this goal, including those using chemical reagents, fixed catalysts, 
and high-energy oxidation.
    KFX's K-Fuel is a processed coal derived from western 
subbituminous coals. It is lower in ash, higher in BTU value, and 
produces lower pollutant emissions than the parent coals. K-Fuel is 
processed in two-steps--physical separation and thermal processing--to 
produce a fuel that is higher value and ``cleaner'' than the original 
coal. The process involves elevated temperature and pressure, greatly 
reducing the moisture content of the coal. The mercury is volatilized 
and subsequently captured in a carbon-bed reactor.
    Powerspan-ECOTM is a post-combustion multi-pollutant control 
technology. It consists of a high-energy oxidation reactor followed by 
an ammonia-based scrubber and a wet electrostatic precipitator, which 
captures the products of oxidation. Fertilizer byproducts are generated 
(ammonia nitrate and sulfate), which should contribute to the overall 
economics of the technology.
    While NESCAUM's new report focused on the above four mercury-
specific control technologies as those closest to commercialization, 
the Subcommittee should be aware that several additional mercury 
control technologies have also emerged from the laboratory and are now 
being tested, including EPRI's ``Toxecon'' process, the use of flyash 
as a sorbent at GE Power Systems and CONSOL Energy, promising chemical 
(vs. physical) sorbents at Amended Silicates/ADA Technologies, and 
various metal amalgamation approaches. The fact that several of the 
above approaches were not even in existence 2-3 years ago illustrates 
the rapid pace of research in the area of mercury controls.

Barriers to the Development of Mercury Controls for Power Plants

    Due to the pace of technology development, the only real remaining 
barrier to controlling mercury emissions from power plants is not a 
question of technology; it is a question of will: it is the current 
absence of the regulatory driver needed to create the opportunity--the 
demand--for mercury control technologies to come to market. At this 
point, coal-fired power plants are not installing aggressive mercury 
control technologies because they cannot do so; they aren't simply 
because there is no requirement for them to do so.
    In September 2000, NESCAUM issued a report summarizing an in-depth 
study of the technology-forcing effects of environmental regulatory 
requirements.\3\ This study looked at the regulation of nitrogen oxide 
(NOX) emissions from coal-fired boilers, sulfur dioxide from coal-fired 
boilers, and automobile emissions. It concluded that regulations with 
well-defined targets and compliance deadlines drive innovation in 
control technology, resulting in dramatically lower implementation 
costs than initially projected. Similar analyses of approximately a 
dozen major regulatory initiatives ranging from CFCs to landfill 
leachate show that initial cost estimates were at least double the 
actual costs and often far higher.\4\
---------------------------------------------------------------------------
    \3\ NESCAUM, Environmental Regulation and Technology Innovation: 
Controlling Mercury Emissions from Coal-Fired Boilers, September 2000. 
See www.nescaum.org.
    \4\ Worldwatch Institute, Working for the Environment, Paper #152. 
See www.worldwatch.org.
---------------------------------------------------------------------------
    Simply put, the principal barrier to the development of cost-
effective controls for mercury emissions from power plants has been 
EPA's failure to date to establish an appropriate MACT standard for 
this sector, and we have no doubt that the documented history of 
regulatory-driven technology innovation and cost reduction will repeat 
itself if and when EPA does establish an appropriately stringent 
mercury MACT standard.
    Coal-fired boiler operators suggest that EPA proceed only 
gingerly--if at all--with mercury reduction requirements because, they 
claim, there are no ``commercially available'' mercury control 
technologies. This suggestion dovetails closely with the above 
discussion of barriers. When does an ``available'' technology become 
``commercially available''? When it provides competitive advantage to 
the buyer, or when the buyer is required to modify its practices to 
meet a larger societal need, e.g., through regulation. ``Commercial 
availability,'' then, resembles a ``chicken or egg'' scenario. Which 
comes first, ``commercial availability'' or regulatory obligation? Per 
the above discussion concerning barriers, history shows that well-
designed regulatory requirements with appropriate lead times result in 
the commercialization of technological innovation, not vice versa.
    Let's also consider precisely what industry opponents mean by 
``commercial availability.'' Southern Company recently indicated that 
``There are currently no commercial technologies that are available for 
controlling mercury from coal-fired power plants. There are no vendors 
that are offering process systems that are supported by guarantees from 
the vendor for mercury control performance under all the conditions 
that an ordinary power plant is expected to encounter over the course 
of normal operating conditions and timelines'' [emphasis added].\5\ 
These caveats suggest that industry seeks zero risk regarding mercury 
control performance, which leads me to wonder if it would accept a 
corresponding zero percent return on any mercury control investments 
made under such caveats.
---------------------------------------------------------------------------
    \5\ Monroe, L., Southern Company, from Mercury Rising, UtiliPoint 
IssueAlert, July 15, 2003. See www.utilipoint.com/issuealert/
print.asp?id=1749.
---------------------------------------------------------------------------
    In sum, we need to expose the ``commercial availability'' argument 
for the red herring that it is. Other red herrings lie in the wings, 
including (a) the technologies don't deliver good results all the time, 
(b) the cost is too high, and (c) the technologies can't be installed 
in time. History shows that market forces will capably address each of 
these concerns. Technology rapidly gets the kinks out and becomes 
reliable, costs drop dramatically, and the market gets the job done on 
time. But that won't happen until there is a market, and there won't be 
a market until there is a driver--a stringent mercury MACT.
    In conclusion, I am reminded of an aphorism that arose during 
earlier NOX negotiations with the power sector, but seems no less 
applicable to mercury emissions: ``Ask an engineer to do something, and 
you get nothing but problems. Tell an engineer to do something, and you 
get nothing but solutions.'' Today, we are getting significant mercury 
reductions as co-benefits from non-optimized controls for other 
pollutants. We have full scale tests on new, cost-effective control 
technologies that reduce mercury substantially from a variety of coals. 
And we have new, even more promising mercury control technologies 
coming out of the labs. Let's tell our power sector engineers that it's 
time to reduce mercury emissions by 90 percent and begin to reap the 
public health and environmental technology benefits that the resulting 
market will bring forth.

                               Discussion

    Chairman Ehlers. Thank you all very much. In response to 
your last comment, I should defend engineers, but I won't. But 
I would mention the way to get a physicist to solve a problem 
is to tell them that there is no solution possible, and you 
will soon have ten different solutions.

           Lessons Learned From the State of Florida Research

    Very good testimony. And a number of questions that I have, 
I think we are going to need a second round just to accommodate 
my questions. But I am trying to--well, Dr. Krabbenhoft, first, 
were you involved in the work in the Everglades, and can you 
tell us what we learned from the experiment there following the 
regulation of the incinerators in Florida? And I should 
mention, even though most of the discussion has been about 
power plants burning coal, the first regulations were on 
medical incinerators, which tend to have a lot of mercury in 
them because of the medical products. So that has been 
regulated for some time. Can you enlighten us on what has been 
learned so far with that?
    Dr. Krabbenhoft. Yes, Mr. Chairman. I have been working on 
the mercury issue in south Florida since 1995. Over that period 
of time, we have learned a lot about what controls mercury 
cycling in the environment.
    In short, over the past five or six years, there has been a 
notable decline in fish mercury concentrations observed in 
sport fish particulate gas and it is to the level of about a 60 
or 70 percent reduction in fish tissue concentrations. Over 
that same period of time, the State of Florida has concluded 
that this reduction in fish tissue concentration is related to 
the rules that were implemented around 1990 that had an effect 
on municipal and medical waste incineration in south Florida to 
reduce mercury emissions in the southern peninsula of Florida. 
This corresponding reduction in fish mercury concentrations has 
been linked to that. They have done modeling exercises to see 
if that level of reduction in air emission sources could result 
in those fish mercury concentration declines, and the answer 
was, in short, yes.
    That is one of the rare examples, here in the U.S., where 
you can look at an air emission reduction and infer what 
happened ecologically.

       The Difference Between Methylmercury and Elemental Mercury

    Chairman Ehlers. Let me just ask a few questions to improve 
my understanding. My understanding is that the only real risk 
is from methylmercury, that the elemental mercury that is out 
there, the mercury oxides, chlorides, and so forth don't really 
seem to pose a health risk, but just the methylmercury. Is that 
correct? And that is because it is absorbed by living organisms 
and then concentrated on the food chain. Is that a correct 
statement?
    Dr. Krabbenhoft. Yes, the fraction of mercury in the 
environment that is methylated typically, say, in sedimented 
water, is less than one percent to a few percent, a very small 
fraction of the total pool. But it is that small fraction that 
by the time you get into the part of the food web where you 
would consume, say, a top predator fish, it essentially 
comprises all of the mercury in those fish tissues. So that 
inorganic fraction, the oxides of the elemental mercury, does 
not bioaccumulate to the top levels of the food web. So it is 
that fraction of the mercury that humans and other top 
carnivores or predators are exposed to.

                Human Response to Methylmercury Exposure

    There are also biochemical reasons in our bodies as well as 
other vertebrate organisms that allow methylated mercury to get 
into parts of our bodies that the inorganic fraction does not. 
So that is in addition to not only bioaccumulation aspects, but 
also biochemically. It behaves differently once in our bodies.
    Chairman Ehlers. The Mad Hatters became ill simply because 
they had such a huge concentration of elemental mercury they 
were working on.
    Dr. Krabbenhoft. That was a case of just gross exposure to 
the inorganic mercury, correct.
    Chairman Ehlers. Yeah. All right.

                      Fresh Water vs. Marine Water

    You made the comment about marine--you know a lot more 
about fresh fish consumption and pollution than marine. What is 
the likely difference? Is it the minerals in the water in the 
ocean that make the difference or you don't know whether the 
mercury is distributed worldwide. What is the difference?
    Dr. Krabbenhoft. The key difference is that in most 
freshwater systems, because they are much shallower than the 
ocean, scientists call upon mercury methylation to occur at the 
sediment water interface. Therefore, the likelihood of that 
methylmercury production zone being linked to the food web is 
not hard to imagine at all. However, in the ocean where you 
have thousands and tens of thousands of feet of separation from 
where the harvestable fish are swimming. From the bottom of the 
ocean where it may be methylated, it is very difficult to come 
up with a reasonable or plausible link between a sedimentary-
based methylation site and fish swimming near the surface of 
the ocean. That is the problem that we just can't come up with 
a conceptual model that is reasonable based on our freshwater 
experience. Therefore, several of us are proposing links to 
coastal margins, actually, food web links of those marine 
fisheries to coastal margins.
    Chairman Ehlers. To what extent are the ocean fish 
contaminated with mercury compared to the freshwater fish?
    Dr. Krabbenhoft. Some of the highest levels of mercury in 
fish, on average, in fact, are from the marine fish.
    Chairman Ehlers. Really?
    Dr. Krabbenhoft. Yes.
    Chairman Ehlers. And what is the concentration of 
methylmercury in the ocean water compared to freshwater?
    Dr. Krabbenhoft. We can use the example that if we use our 
standard procedure, which is the best going right now, we would 
take a freshwater sample and analyze methylmercury from it and 
we apply that procedure to ocean water, we can not detect 
methylmercury. If we use adapted procedures with much higher 
volumes and stripping methylmercury out of a larger volume, we 
can measure it. But the methylmercury in any case in ocean 
water is extraordinarily low. And that is part of the 
conundrum. How can we get such high levels in these marine fish 
when the levels are so extraordinarily low?
    Chairman Ehlers. Unless they eat an extremely greater 
amount of fish, of smaller fish.
    All right. My time has expired. I will recognize the 
Ranking Member, Mr. Udall.

       Development of Specific Technologies for Mercury Abatement

    Mr. Udall. Thank you, Mr. Chairman. I, too, want to thank 
the panel. And your testimony has been very educational.
    If I could, I would start with Mr. Colburn. In your written 
testimony, you state that current technologies can achieve an 
impressive, I think, 95 percent reduction of mercury in power 
plants. I think what is remarkable about it is in part because 
this is shown even in the absence of specific controls for 
mercury. Since 95 percent of mercury can be removed as a co-
benefit, is there a need for the development of specific 
mercury control technologies?
    Mr. Colburn. I think, Congressman, that that is really a 
function of letting the market pick the best solution.
    Mr. Udall. Uh-huh.
    Mr. Colburn. We should require a mercury reduction result, 
and then if individual plants in their market conditions can 
achieve that through co-benefits, more power to them. If they 
need mercury-specific control technologies to achieve that, 
then market options should be there for them to do so. The 
principle reason, as I see it, that most of those plants 
performed as well as they did is because they have a fine 
particulate matter control technology called a baghouse or a 
fabric filter. There is carbon in the gas. That allows 
absorption with mercury. The baghouse provides greater 
coverage, greater residence time, a greater exposure to the 
carbon by the mercury, and thus, more is removed. Baghouses 
aren't rocket science, and they could be installed on other 
plants, if the plants chose that as their route. But that is 
being done today.
    The oxidation opportunities that Dr. Offen mentioned are 
also significant and I suspect that several of those plants 
also had SCR before the baghouse, but those technologies exist. 
The reason other plants have done less well is many of those 
plants don't have baghouses. Does that answer your question?
    Mr. Udall. That is helpful. Yes.
    Dr. Offen, would you like to comment on that particular 
question or add your comments?
    Dr. Offen. Yes. There were a number of comments that were 
made. What Mr. Colburn said was correct about the plants that 
have very high removals. They do have, typically, spray dryers 
and baghouse combinations, the particular set of controls that 
work very well on low-sulfur coals. They have to be eastern 
low-sulfur coal so they have enough chlorine in there to make 
all three work together.
    What Mr. Colburn said about unburned carbon is also 
correct. For those plants that aren't able to burn the coal out 
totally and have some residue carbon left in there, that will 
help as long as the temperature where the particulate 
collection device is low enough. All of these are site-specific 
factors, so depending upon the plant situation, you would have 
to add other controls to get to any increased levels, 
especially those plants that are in the 10, 20, 30, and 50 
percent range.

            Federal Regulation's Effect on Mercury Reduction

    Mr. Udall. Back to you, Mr. Colburn, again. You had some 
remarkable results, as we were mentioning, in the Northeastern 
States. And from what I understand, you did this in part 
because these municipal waste combustors had higher standards, 
three times as high as the federal standard. How important is 
it that federal mercury regulations allow States to institute 
more stringent controls than federal law prescribes? If the 
Northeastern States had not been able to increase control 
standards, in other words, preempt federal laws, could the 
Northeast have been successful in achieving this 55 percent in 
regional reduction?
    Mr. Colburn. We certainly would not have been able to 
achieve it, Congressman. If we had been limited, if the States 
did not have the opportunity to provide further protection to 
their citizens, it couldn't have been done. I should add, 
Congressman, that the sources have actually controlled about 
three times better than even the States required. We have been 
here and have done that as far as mercury controls on municipal 
waste combustors go. No, we just need to give the power plant 
sector the same motives to move forward with both the 
information needs that Dr. Offen mentioned and the control 
technology installations.
    Mr. Udall. So you are saying the combustors went three 
times beyond what the States were requiring which was three 
times beyond from the federal standards?
    Mr. Colburn. Yes. The federal standard is typically 80 
micrograms per cubic meter. The States typically did a standard 
of 28. And the municipal waste combustors are operating in the 
5 to 10 area.

       Relationship Between Government Regulation and Technology 
                              Development

    Mr. Udall. Dr. Offen and Mr. Colburn, one of my worries is 
that we lag behind if we don't put these new standards in 
place, lag behind other countries in the development of their 
technologies. Do you foresee a point in which if we don't make 
it clear what our standards are that, when we do, because I 
think this is a matter of not whether but when and how, that we 
will actually be buying that equipment and generating that 
technology from other countries as opposed to within our own 
environmental technology sector?
    Mr. Colburn. Congressman, I think that is not only a 
perceptive point, I think that is an accurate one. I had one 
technology vendor recently say to me that the showstopper for 
their technology creation and development would be if there is 
not a good mercury MACT rule. And I think that is 
representative of the other technology developers out there.
    An interesting calculation, I certainly don't have it at 
the tip of my tongue, would be how many jobs are there in the 
control development manufacture and installation side of the 
coin versus the power plant operation and extraction 
industries? I wouldn't be surprised if the delta between those 
two is smaller than any expect.
    Mr. Udall. I see my time has expired, but I did want to 
mention and show the Chairman as well, that on the coal 
consumption, a million ton basis, China and the U.S. add up to 
about 50 percent. And I am curious if the Chinese are 
developing any of this kind of technology. And if they are not, 
then, of course, we are in a race with the EU countries, I 
would imagine, and perhaps Japan in fighting this technology 
with the Chinese, which would be an enormous market for us. 
Would that be correct from what you understand?
    Mr. Colburn. I don't have direct knowledge of that, but I 
have no reason to dispute the conclusion that they must be 
looking at that.
    Mr. Udall. Thank you, Mr. Chairman.
    Chairman Ehlers. The gentleman's time has expired.
    Next, we recognize the gentleman from Minnesota, Mr. 
Gutknecht.

                  How Federal Agencies Are Responding

    Mr. Gutknecht. Thank you, Mr. Chairman. And I was deadly 
serious, I have become incredibly interested in this subject. 
And the more I learn about it, sometimes, it is more disturbing 
what I learn is out there.
    First of all, I guess I would ask all four of you maybe to 
just respond as briefly as you can. Do you think that the EPA, 
the CDC, the FDA, and the other agencies that are involved in 
this are taking this issue as seriously as they should? Dr. 
Burke.
    Dr. Burke. Great question. I think they are taking it very 
seriously. They interacted very actively with the National 
Academy. They have active research at CDC, surveillance of the 
population at EPA, the development of regulatory approaches as 
well as research, and the FDA has been doing a lot of fact-
finding. Unfortunately, they take three different directions 
sometimes, and we have not had a unified approach to really 
look from source to exposure to health endpoint, but I think 
that is beginning to take shape. Yes, they are taking it 
seriously.
    Dr. Krabbenhoft. I interact with agency members from most 
of the agencies that you listed there, and my conclusion is 
they take it very seriously. They don't necessarily agree, but 
my conclusion is they take it very seriously.
    Dr. Offen. Of course, I will switch to the control 
technology portion of what they are doing. And as I mentioned 
in my discussion, we work very closely with the Department of 
Energy but also with the EPA. We co-fund projects, and they 
were participants in all of the field tests that led to the 
graph that is at the end of your package, for example. So the 
answer is definitely yes.
    Mr. Colburn. Congressman, I would basically agree with the 
other three witnesses. I would also include the private sector, 
because they are taking it very seriously in terms of 
technology development. I guess the only equivocation I would 
have is that one does have to recall that EPA needed to be 
compelled through Court Order to issue the MACT rule at the end 
of this year and then to finalize it at the end of next year.
    Mr. Gutknecht. That is part of the reason I raised the 
question. And I think you all eluded to it that, even in the 
consumption of fish, we have different agencies essentially 
saying different things. Now I am not sure that that is 
necessarily a bad thing, but I am also concerned, and this is a 
parochial interest, and part of the reason that has gotten me 
interested in this and I can't remember which one of you 
mentioned this, about the lack of setting clear standards. For 
example--I would assume some of you are familiar with the 
process of retorting and that actually, at one time, there were 
ten firms involved in that and now we have two, in part because 
the EPA has not promulgated the rules, which I think everyone 
assumed that they would.
    Dr. Krabbenhoft, I see you were shaking your head. Is that 
okay?
    Dr. Burke. Let me try and sort out the question there. 
There has been a lot of uncertainty about the science, but 
clearly there are different missions for the agencies involved, 
which has led to different approaches to how they have gone 
about their efforts to limit mercury exposure and the health 
effects. I think EPA has been a leader in the research and 
pushing forward with the evaluation of the epidemiology. But 
clearly, there have been different points of view from CDC and 
FDA. I think this has led to some confusion and ultimately to 
the National Academy study, which we feel has unified the 
database, has looked across the endpoints of animal and human 
data and really tried to put an end to the different 
interpretations and come up with some definitive 
recommendations about the effects seen in the human 
epidemiology, provides a strong basis for EPA to move forward 
with the RFD, and that the scientific basis of the actions, 
although they might have different responsibilities, should be 
uniform across the agencies.

                               Thimerosal

    Mr. Gutknecht. Let me just ask one last question, and I see 
the yellow light has already come on.
    One of the other things, Dr. Burke, you mentioned unborn 
children. And what about small children and the use of--I 
believe it is called thimerosal. And I understand have been 
studies and some back stepping and so forth on that whole 
issue. What is your view?
    Dr. Burke. Well, I understand today there was a--the 
American Academy of Pediatrics came out with some new evidence 
that thimerosal in vaccines was not related to adverse effects. 
I have only heard that through the press. I think there is a 
lot of uncertainty, particularly at the very low doses that we 
are talking about. And there are questions about when is the 
most vulnerable period of development? Is it in utero? Is it 
small children? We know the brain is very busy developing in 
small children. We also know that mercury is a strong 
neurotoxic agent, but we don't have all of the answers. I think 
that is why we depend upon the epidemiology from the most 
sensitive, the children exposed in utero. But frankly, there 
are effects throughout the life span, including cardiovascular 
effects on middle-aged men that we are just beginning to 
understand and sort out.
    Mr. Gutknecht. I see my time has expired, and I might come 
back to that, because when you have small, underweight children 
and you give them three booster shots all in the same day, they 
are getting upwards of 75, is it microliters, or whatever the 
term is. I mean, it seems to me that is a pretty good jolt to 
anybody's system.
    Dr. Burke. There was concern, particularly about the 
premature infants and the regime of vaccination and a movement 
toward phasing out thimerosal as a preservative. It has 
important benefits. Vaccinations have been a tremendous public 
health breakthrough, but we have to balance those. And right 
now, the news appears to be good.
    Mr. Gutknecht. All right. Thank you.
    Chairman Ehlers. The gentleman's time has expired.
    Next we call on the gentleman from Maryland, Mr. Gilchrest.

     What Happens to Mercury When It Enters the Natural Environment

    Mr. Gilchrest. Thank you, Chairman.
    Just to, maybe, Mr. Burke and Dr. Krabbenhoft. I was 
looking at it to make sure I pronounced your name right.
    Three forms of mercury, or the three that were mentioned 
here, at least, oxidized, elemental, and methylmercury, are 
they all persistent in the environment, or do any of them 
biodegrade in the natural environment?
    Dr. Krabbenhoft. Those forms of mercury all interconvert, 
some on a very rapid basis. So if we go out and take a sample 
and have a certain percentage, say and a sample has 
methylmercury, we can come back a few months later and see a 
very different signal, because there are----
    Mr. Gilchrest. So it might go from methyl to elemental to 
oxidized?
    Dr. Krabbenhoft. Yes. There is a constant interconversion. 
Now is there any----
    Mr. Gilchrest. Is there a difference in freshwater in 
estuary or the marine environment? Would that change?
    Dr. Krabbenhoft. I have--certainly for the marine system 
there is not enough information to give you an answer.
    Mr. Gilchrest. Could it change inside the fatty tissue of a 
fish from methyl to elemental to oxidized?
    Dr. Krabbenhoft. Certainly methylmercury could be 
demethylated to the oxidized inorganic mercury in our bodies, 
and that is one of the things that does happen, yes. But it is 
very slow----
    Mr. Gilchrest. So it is not likely to change while it is in 
the fatty tissue of a fish?
    Dr. Krabbenhoft. It actually doesn't go to the fatty 
tissue. It goes to the muscle.
    Mr. Gilchrest. Oh.
    Dr. Krabbenhoft. That is the difference between mercury and 
most other contaminants of concern. And that is why you can't 
filet it out or cook it out.
    Mr. Gilchrest. But methylmercury is the dangerous form of 
mercury that could cause health effects as opposed to elemental 
and oxidized mercury?
    Dr. Krabbenhoft. None of them are good for us----
    Mr. Gilchrest. Okay.
    Dr. Krabbenhoft [continuing]. That is for sure. 
Methylmercury is more toxic gram per gram than the others for a 
variety of reasons that probably Dr. Burke is more qualified to 
answer.

                   Scientific Basis for EPA Standard

    Mr. Gilchrest. Is it--Dr. Burke, you mentioned that the 
National Academy of Science has tried to find some uniform, I 
guess, system to determine is it safe levels of mercury in 
humans and have they come up with a unified statement or policy 
on that?
    Dr. Burke. The National Academy report reviewed the body of 
evidence and make recommendations to EPA. It reviewed the basis 
for the EPA standard, which at that time, was based upon a 
poisoning episode in Iraq. And we are most concerned about 
dietary, consumption of fish that have mercury. So we 
recommended they change the basis for their standard and use 
the human epidemiology and provided a presentation of that 
information, yes.
    Mr. Gilchrest. So NAS made a recommendation to EPA for EPA 
to change the standard they had been using?
    Dr. Krabbenhoft. Change the scientific basis for it.
    Mr. Gilchrest. Oh, I see.
    Dr. Krabbenhoft. In fact, what we did was reaffirm the 
standard that they were using, because within that range, that 
appears to be a range with levels of uncertainty that would be 
protective----
    Mr. Gilchrest. So you are saying EPA pretty much had it 
right already?
    Dr. Krabbenhoft. EPA had it right, but we refined the basis 
for that being maternal exposure, through diet, through fish.

                     Mercury in the Chesapeake Bay

    Mr. Gilchrest. So in an estuary like the Chesapeake Bay, 
what would be the prime source of mercury, methylmercury in 
particular? Would it be coal-fired power plants?
    Dr. Krabbenhoft. The knowledge I have of the Chesapeake, 
and there are research projects that are going on right now, 
and I believe I have them accurately that the majority of the 
methylmercury is made in the sediments of the Chesapeake 
itself, but it is----
    Mr. Gilchrest. When you say it is made in the sediments of 
the Chesapeake itself, what do you mean?
    Dr. Krabbenhoft. The mercury that comes into the Chesapeake 
is overwhelmingly the inorganic, oxidized form both from air 
deposition and from runoff. And the runoff gets contributions 
from a wide variety of sources.
    Mr. Gilchrest. From as far away as Ohio?
    Dr. Krabbenhoft. Those would have to be air deposition, but 
certainly that is not implausible at all. But once in the 
ecosystem, that mercury that deposits either on streams that 
drain into the Chesapeake or directly on the Chesapeake itself 
quickly descend to the sediments. And there, a fraction of that 
mercury gets methylated. So it is converted in the environment 
to methylmercury. And so the majority of the methylmercury in 
the Chesapeake----
    Mr. Gilchrest. How long does it take to go from the 
oxidized form to methylmercury while it is in the Bay?
    [No response.]
    Mr. Gilchrest. That will vary depending on the 
circumstances?
    Dr. Krabbenhoft. It varies depending upon the 
circumstances, but in short, what we have seen in our 
environment studies is this transformation is very fast.
    Mr. Gilchrest. So the main source, whether it is the 
drainage from the land to the streams to the Bay or from air 
deposition, what would be the main source of that mercury, 
oxidized, elemental, or methyl? Is that--I mean, other than 
human activities, is it automobiles, incinerators for medical 
waste, coal-fired power plants?
    Dr. Krabbenhoft. I have not seen a mass balance, if you 
will, for Chesapeake Bay itself. Researchers who I know are 
doing that have done the calculations to suggest that most of 
the mercury, I believe, comes in through the sky----
    Mr. Gilchrest. I see.
    Dr. Krabbenhoft [continuing]. And rains directly on the 
Chesapeake that way. And that is generally the calculation 
results that direct deposition is most important.
    Mr. Gilchrest. Would you recommend that every fishing hole 
in the Chesapeake Bay and its tributaries have a sign talking 
about the contamination of methylmercury or is that not a 
problem to fish?
    Dr. Krabbenhoft. Go ahead.
    Dr. Burke. If I may help with this, the inland waterways, 
the rivers throughout Maryland actually have fishing 
advisories. The Bay itself----
    Mr. Gilchrest. Well, I live there, and I don't see a lot of 
signs posted----
    Dr. Burke. No, the signs aren't there, but the advisories 
are there.
    Mr. Gilchrest. Should the signs be there? The advisories 
are in the newspaper every once in a while.
    Dr. Burke. They should be there. They should be on the 
licenses, and we should have, as best we can, the best 
information we can have out there on the levels in inland 
waterways, not just in Maryland but throughout this country. In 
44 of the States we have this problem. They are elevated. The 
levels from outside in the Bay appear to be lower, though.

       The Basis for National Academy of Science's Recommendation

    Chairman Ehlers. The gentleman's time has expired. We will 
start a second round of questioning.
    And Dr. Burke, I would like to ask you a few questions 
about the studies on which your work was based. First of all, I 
am interested in the Seychelles study, which I understand, 
initially was just regarded as not having appropriate technique 
and so forth. So when the National Academy did their work, they 
basically disregarded that in setting their number. Now I 
gather from your testimony that with additional work down 
there, the Seychelles study has achieved some respectability. 
Now are they showing an effect at this point? Are they still 
showing very little epidemiological evidence of disease from--
--
    Dr. Burke. Right.
    Chairman Ehlers [continuing]. Eating the fish?
    Dr. Burke. First of all, the National Academy did not 
disregard the Seychelles study. In fact, they very carefully 
evaluated that as well.
    Chairman Ehlers. Well, I am sorry.
    Dr. Burke. Yeah.
    Chairman Ehlers. That was a strong word to use.
    Dr. Burke. Okay.
    Chairman Ehlers. You didn't incorporate that----
    Dr. Burke. But we didn't use it for the basis of our 
recommendation, you are correct.
    Chairman Ehlers. Yeah.
    Dr. Burke. But we have always felt it is a well-conducted 
longitudinal study. And the update also sheds new light on the 
potential impacts. What we recommended, though, that for public 
health protection, when there are two positive studies, there 
really isn't a sound justification for using the negative study 
as the public health basis for moving forward. This update, I 
might add, did address one of the questions that we had, and 
that was that perhaps the children were young when they were 
evaluated and it was hard to get reliable test data. And now 
that the kids are a little bit older, we feel that they really 
validate and continue to improve their observations and move 
forward.
    But it is a well-conducted, sound study.
    Chairman Ehlers. Is that--is it coming into agreement, 
then, with the other studies or is it too early?
    Dr. Burke. No, it is not showing positive effects. The 
other ones do show detrimental impacts on neurodevelopment. 
Seychelles does not.
    Chairman Ehlers. How do you explain that, and why would you 
pick the ones that show positive effects and not the one that 
shows negative effects or null effects, I should say?
    Dr. Burke. That is an important question. Our fundamental 
goal is to protect public health. And with two well-conducted 
studies that do show an effect, a public health based standard, 
the long-standing protocol to go about this is to select a 
critical study and a critical effect and use that to go 
forward, informed by the other studies as well. So the 
uncertainties introduced by the Seychelles were important, 
however, the data from the other two studies and the overall 
weight of the animal testing really provided, we think, a 
sound, scientific basis.
    Chairman Ehlers. So it was a combination of the animal 
studies plus----
    Dr. Burke. A wide variety of human observational studies 
throughout time, including poisoning episodes, as well as these 
three very important epidemiological studies.
    Chairman Ehlers. Did you determine anything about the type 
of mercury that was involved in the study? Was it all 
methylmercury that basically did the damage?
    Dr. Burke. Yes, by measuring both maternal hair and cord 
blood, we feel that the primary source was fish consumption and 
therefore it would be the methylmercury form.

                 The Effect of Regulation on Innovation

    Chairman Ehlers. Okay. I am becoming thankful that I don't 
particularly enjoy eating fish. But that is not true of most 
people in my State.
    Dr. Offen, I want to ask you about the testimony of Mr. 
Colburn in which he indicated that if we have the requirement, 
then there will be more innovation. It is another way of 
saying, you know, necessity is the mother of invention, that 
once we set a standard, there will be a scramble to produce 
cost-effective methods of controlling mercury emissions. Is 
that something that you would agree with?
    Dr. Offen. There is no doubt that if a standard--when the 
standard is set, the industry will meet it as they are going to 
abide by the law. I think the only question that I would raise 
is at what level and how fast. I would also like to point out 
that even in the absence of a standard, but yet in the 
expectation of standards, the industry has been spending quite 
a bit of money on mercury. Our program, as I made mention, has 
been going on for 15 years. And right now, at EPRI, within the 
programs that deal with power generation, EPRI also covers, you 
know, transmission distribution, nuclear, et cetera, but within 
fossil power generation, the mercury control research work is 
the largest effort that we have. So there is some substantial 
amount of work that is going on right now.
    I would hark back to the experience we had with scrubbers 
in the early '70's as sort of a guiding principle, maybe an 
experience-based principle. Those were mandated and because of 
the building boom and the economic growth we had at that time, 
a lot of the power plants were built and therefore a lot of 
scrubbers were built in a very short period of time. About a 
year or two or three later, most of them--or many of them had 
quite a bit of serious trouble. And from a researcher's 
perspective, that was good, because that gave us a $10 million 
a year for 10- or 15-year program, but for the economy, it 
maybe wasn't so good. I think that is where the concern is with 
statements that if you just mandate it, the solution will be 
there no matter what the time schedule is and what the level 
is.
    Chairman Ehlers. So you are saying mandate it and then give 
some time for the research and development to take place?
    Dr. Offen. For the research to be completed that is already 
well underway.

         Department of Energy Effort to Create New Technologies

    Chairman Ehlers. Yeah. All right. You have mentioned the 
DOE program that they were doing. Is this to develop new 
control technology, or is there----
    Dr. Offen. I am obviously speaking secondhand here, since I 
am not from DOE, sir.
    Chairman Ehlers. Yes.
    Dr. Offen. But in the work that we are doing with them and 
that we are familiar with, they are doing both development and 
evaluation. And the field tests program that I mentioned where 
we will be testing for one to two months at 16 different sites 
I would categorize as evaluation. But they have quite a few 
programs where they are also developing work. They have two 
processes they have developed themselves that they have also 
promoted, for example. These go along in parallel, because you 
just never know which process is going to be successful. And 
secondly, you don't know which is going to be the most cost-
effective. And the paradigm, if I could say so, in the power 
industry, has been that the power industry needs options, 
because every plant is so different from every other plant. 
That is why we see 10 to 90 percent reductions right now.
    Chairman Ehlers. Yeah. And every lump of coal is different 
from every other lump of coal.
    When do you expect the DOE work and your work to be able to 
give some definitive answers as to what is the best and what 
are the most cost-effective control technologies?
    Dr. Offen. That is a difficult question to answer, because 
it depends on the success we have. If the current programs are 
successful and we get good results, we will know a lot more in 
2006 than we do now when the programs are over. If we continue 
to have a different line for every power plant and can't 
understand why, it will be longer.
    Chairman Ehlers. I see.
    Dr. Offen. As my written testimony said, what we see as the 
biggest uncertainty is our understanding of mercury chemistry.
    Chairman Ehlers. Well, I have kept going on because we 
didn't have any more Members. But my time is expired. Mr. 
Gilchrest, do you have additional questions?
    Mr. Gilchrest. Just a couple.
    Chairman Ehlers. Go ahead.
    Mr. Gilchrest. I was interested in your line of 
questioning, though.

        The Cause of the Decline of Mercury in the Florida Study

    I understand that mercury is not biodegradable. Just stop 
me if I am wrong with any of this. But it accumulates in the 
environment. It never goes away. It might change from one form 
or another, depending on the conditions, but it basically, for 
all intents and purposes, is persistent.
    Dr. Krabbenhoft, when you made a comment about reducing the 
source of mercury in Florida, you saw a corresponding decline 
of mercury in the environment. Does that mean that the mercury 
in the environment was decreasing or just not increasing?
    Dr. Krabbenhoft. First of all, your question about the 
biodegradability of mercury, that is absolutely right. Mercury 
is one of the elements, and as such, it can neither be created 
or destroyed. It is there. That separates it from many of the 
contaminants of concern.
    Mr. Gilchrest. And can a physicist, maybe believing in the 
string theory, corroborate that comment or----
    Chairman Ehlers. Well, I would have to disagree with the 
statement, of course, because physicists can't create or 
destroy mercury. But that is beside the point for this when you 
are talking about it as part of the biological system. He is 
absolutely correct.
    Dr. Krabbenhoft. With regard to the specific question about 
Florida, the waste streams in south Florida and the combustion 
systems in south Florida were heavily dominated, unlike many of 
the other areas of the country, by medical and municipal waste 
incineration. They do not burn, essentially, any coal for power 
production in south Florida. It is different than many other 
places. But because they burn a disproportionately high amount 
of medical and municipal waste in south Florida, the rules that 
were in place around 1990 to eliminate or reduce mercury into 
those waste streams had a, probably, larger effect in south 
Florida than other parts of the country. And so the State of 
Florida has estimated reductions in mercury emissions from 
their local emitters on the order of 70 or 80 percent.
    Mr. Gilchrest. But the mercury that was there prior to 
1990, is it still there?
    Dr. Krabbenhoft. Is the mercury there by and large, yes. 
Now mercury does re-emit as well, so if mercury rains down from 
the atmosphere onto water or land, it is fully capable of being 
reduced largely from photochemical reactions from the sunlight, 
UV reactions, back to gaseous mercury, and then it goes back to 
the sky.
    Mr. Gilchrest. What percentage of mercury does that, then, 
would you say?
    Dr. Krabbenhoft. It is generally not big, on the order 
annually of, say--our dosing experiments in the field suggested 
somewhere around the order of, say, five or 10 percent or so.

                     Eliminating Mercury Emissions

    Mr. Gilchrest. Mr. Colburn spoke about his success in 
scrubbing out mercury in maybe somewhere around 2015 actually 
eliminating all of the mercury that is being emitted by fossil 
fuel power plants. Is that a fairly accurate statement?
    Mr. Colburn. The entire elimination, Representative, the 
Governors didn't put a date on that. They wanted 70 percent--75 
percent by 2010 and then just to keep working beyond that.
    Mr. Gilchrest. I see.
    Mr. Offen, is that an achievable goal for the rest of the 
country what New England seems to be doing?
    Dr. Offen. We have not seen 100 percent elimination of a 
pollutant any place.
    Mr. Gilchrest. Well, I am not talking about 100 percent, 
but do you think that what New England has done for a 
projection of 75 percent elimination of mercury from these 
power plants by 2010, is that a goal in any other area of the 
country, that you are aware of?
    Dr. Offen. Again, I will return to my answer to Chairman 
Ehlers. I can't predict how successful we will be in the next 
set of tests. We continue to see quite big differences 
depending upon fuel and the power plant. We see some successes, 
and we see some failures. And it continues that way.
    Mr. Gilchrest. Sure.
    Dr. Offen. Then the other question always is cost. You 
could create a scenario where every plant burned low sulfur 
eastern bituminous coal and had added to their current 
pollution controls a spray dryer and a baghouse and you would 
get down there. I don't know that that is the policy that you 
want to make.
    Mr. Gilchrest. Mr. Colburn, have you benefited from the 
kind of coal that emits less sulfur and less mercury and you 
had other conditions that are different from, let us say, 
Maryland or Texas or California?
    Mr. Colburn. Okay. I think that most of our coal is 
bituminous, and so we, no doubt, have benefited from that as 
opposed to other coals. But today, Representative, most of our 
reductions have been through hazardous waste and municipal 
waste combustors as well. The reductions that we have had from 
coal plants, because that commitment, that 50 percent by 2003 
and 75 percent by 2010, is economy-wide. It is not a power 
plant control. It is an overall mercury emissions goal. And as 
I said, we have met the 2003 one. So while we may have some 
advantages when a mercury control regime is adopted for power 
plants, the only benefits we are getting at this point are 
purely the co-benefits that we all spoke of before.
    Mr. Gilchrest. Thank you.

         Tracking Mercury Once It Has Been Emitted From a Plant

    Chairman Ehlers. The gentleman's time has expired.
    Dr. Krabbenhoft, how well can we keep track of the mercury 
or how well do we keep track of the mercury once it goes up the 
stack? And I am really getting at the local, regional, global 
question. Are we in the process of cleaning up to protect the 
people downwind from the power plant or is this because it is a 
global matter and every nation should be doing it? What insight 
can you give me on that and how well can you measure the 
deposition in the local environment, you know, say 40, 50, or 
60 miles from the plant?
    Dr. Krabbenhoft. The technologies to do that are relatively 
new. By that, I mean probably within the last five years, the 
instruments that can actually be deployed in the field and 
distinguish those forms of mercury. So that has been a 
hindrance that we have only had an instrument capable of doing 
that for a relatively short period of time. If you deploy those 
instruments in the field, you can do a pretty good job of, A, 
measuring what is coming out and few, but some studies have 
actually gone and followed through to watch the 
interconversions that happen post-release. Those are all very 
recent studies. But yes, you can do it. Yes, you can keep track 
of it. Yes, you can then apply models to predict how far it is 
raining out.
    Chairman Ehlers. And what sort of--how many parts per 
million or parts per billion are we talking about when you are 
detecting this?
    Dr. Krabbenhoft. That we are detecting?
    Chairman Ehlers. Yeah.
    Dr. Krabbenhoft. The instruments that are used in the field 
presently can see picogram quality--picogram per meter cube 
quantities, so extraordinarily low.
    Chairman Ehlers. Um-hum.
    Dr. Krabbenhoft. So sensitive that you can't apply it near 
the source, because it overwhelms the detectors.
    Chairman Ehlers. Yeah. Just as a matter of curiosity, what 
methodology do you use?
    Dr. Krabbenhoft. Detection is always done by atomic 
fluorescence. It is a wonderfully sensitive, ancient 
measurement, but it is wonderfully sensitive for mercury. The 
real work is done on the front end for separating out the forms 
using a variety of deneuters and columns and traps, et cetera.
    Chairman Ehlers. Okay. Okay. So you look at the green 
lines, the famous green lines of mercury?
    Dr. Krabbenhoft. Yes.

             Global, Local, and Regional Sources of Mercury

    Chairman Ehlers. What do we know about the quantity of 
mercury emissions from utilities that deposit in the local 
environment? How does that compare to the global load that an 
area may already have?
    Dr. Krabbenhoft. That is an area that, quite frankly, is 
underexposed in terms of our understanding. A vast majority of 
the studies to date have been done in truly remote settings. 
And I really believe the reason for that is just curiosity. How 
could you possibly get this much mercury in the wildlife in a 
setting that is so remote? And because of that, our 
understanding of the near field--near source field is 
underappreciated or underevaluated at this point. But certainly 
where researchers have gone into near field source field 
environments, you see much higher concentrations. So to use the 
example, we have recently collected data in East St. Louis, 
Missouri where we see levels of reactive gaseous mercury and 
particulate mercury on the order of 20,000 to 25,000 picograms 
per cubic meter whereas if we go to a remote location, you will 
see a number of about three. So there is tremendous gradient.
    Now how do those gradients transition? We don't know. We 
need--we definitely need to do more work in those near source 
field areas.
    Chairman Ehlers. And just one other question on that. We 
have largely talked about power plants as being the source or 
incinerators. Are there other sources of this? You mentioned 
the high readings within the urban area. Are there other 
sources that we have around?
    Dr. Krabbenhoft. Other sources of mercury, other than the 
ones that we have discussed today, the power plants----
    Chairman Ehlers. Right.
    Dr. Krabbenhoft. Yes. Certainly other facilities like 
chloralcolyte plants are still a source of mercury today to the 
environment. Another one is metals melting. In fact, the high 
concentrations that I was speaking of in St. Louis, we don't 
believe that is contributed to any substantial degree--by coal 
combustion at all. We believe, in fact, that it is coppers 
melting. So yes, there are other sources that, I guess, haven't 
seen their day yet.
    Chairman Ehlers. Yes. Okay.
    Oh, the staff just reminded me. I haven't gotten to the 
global part here yet of the local, regional, global. Are you 
able to track mercury coming in from other countries and some 
way differentiate it? And how much of the load, on average, 
across the United States is from our own sources and how much 
is from global sources, including our own?
    Dr. Krabbenhoft. Well, if you look at the amount of mercury 
being released to the global environment from the U.S. versus 
the world, it is not a big proportion, five or 10 percent. But 
the real question is how much mercury raining out----
    Chairman Ehlers. Yeah.
    Dr. Krabbenhoft [continuing]. In the U.S. is coming from 
our sources versus global sources.
    Chairman Ehlers. Yeah. And that is my question.
    Dr. Krabbenhoft. That, I personally do not believe we have 
an answer for. The way you have to go about looking at that is 
looking at our own stacks and studies on our stacks, the mass 
account. You do all of the Lagrangian following of that plume 
and watch it through time to see how much of that mass and that 
plume drops out over what distance and understand what the 
footprint of that particular source is. Those kinds of things, 
quite frankly, have not been done, or if they have been done, 
they haven't been done enough.
    Can I or anybody else distinguish Asian mercury coming in 
from European or California mercury by the time you get to New 
England? No.
    Chairman Ehlers. There are ways you could determine it, if 
you wanted to do the experiment. I mean, you could use 
radioactive mercury and track it and see how far it goes.
    Dr. Krabbenhoft. Or even better yet, stable isotopes of 
mercury. We use those all of the time. That is how we do our 
new mercury versus old mercury source, so we wouldn't have to 
release a radioactive form. But yes.
    Chairman Ehlers. Yeah.
    Dr. Krabbenhoft. You can do that. We proposed that once to 
the DOE. It didn't get very far.
    Chairman Ehlers. Well, that is interesting.
    Okay. Yes, Dr. Offen.
    Dr. Offen. Mr. Chairman, I know that some of my colleagues 
at EPRI have looked at that. I am not capable of discussing it 
at any great depth, but with your permission, I would like to 
submit a response to your question, for the record.
    Chairman Ehlers. I would very much appreciate that and--I 
was just going to close, but we will see if Mr. Gilchrest has 
any other questions.
    Mr. Gilchrest. Just a quick question, Mr. Chairman. Thank 
you very much.

            Fish Consumption in the Seychelle Island Studies

    Dr. Burke, in, I guess it is the Faroe Islands, New 
Zealand, the Seychelles Islands, you did studies on the 
vulnerable population of unborn children looking at the amount 
of mercury in their system based on fish consumption.
    Dr. Burke. We looked at mercury exposure to the mother----
    Mr. Gilchrest. Okay. And was that----
    Dr. Burke [continuing]. And related that to developmental 
outcomes in the children.
    Mr. Gilchrest. Was that based on fish consumption?
    Dr. Burke. Yes.
    Mr. Gilchrest. On the level of mercury contamination in the 
fish in these areas, were they all fairly high, pretty similar 
in those three places----
    Dr. Burke. Well, actually----
    Mr. Gilchrest [continuing]. Which is why you chose them?
    Dr. Burke. Well, actually, in the Seychelles, for instance, 
they consumed ocean fish, and they are similar to the levels we 
see in this country. But they consume a very high diet of fish 
with 12 meals a week, which would be very unusual----
    Mr. Gilchrest. Right.
    Dr. Burke [continuing]. Here in the U.S. They were chosen, 
though, because of----
    Mr. Gilchrest. They seem to have----
    Dr. Burke [continuing]. Their dietary patterns.
    Mr. Gilchrest. Yes.
    Dr. Burke. Yes.

                          Effects on Wildlife

    Mr. Gilchrest. So you could say--I mean, I don't want to 
put words in your mouth, but if you evaluated the amount of 
mercury in fish in the Chesapeake Bay, whether they were 
minnows or catfish or rockfish or whatever, would there be 
similar concentrations of mercury in the Chesapeake Bay fish as 
there were in Seychelles?
    Dr. Burke. Well, that is an important question. Actually, 
there is a wide range, like a 20-fold difference in the 
concentrations of mercury, depending upon the species.
    Mr. Gilchrest. Oh, gee.
    Dr. Burke. And the fish we are most concerned about for the 
average consumer are the large----
    Mr. Gilchrest. Right.
    Dr. Burke [continuing]. Predator fish.
    Mr. Gilchrest. So striped bass would be a concern?
    Dr. Burke. Actually, striped bass is--does not have----
    Mr. Gilchrest. Really?
    Dr. Burke. And I might add that crab cakes don't have 
mercury issues as well.
    Mr. Gilchrest. How about oysters? We are pretty safe with 
oysters?
    Dr. Burke. I actually don't----
    Mr. Gilchrest. So which fish in the Chesapeake Bay, then, 
would have high concentration----
    Dr. Burke. The Chesapeake Bay, in general, the--for the 
main body of the Bay, the levels are low.
    Mr. Gilchrest. Fairly minuscule?
    Dr. Burke. It is--right. It is the inland rivers where, 
because of localized sources----
    Mr. Gilchrest. Now when you say inland rivers, are you 
talking--is that----
    Dr. Burke. Like the Back River, where the advisories are. 
It is the inland waterways.
    Mr. Gilchrest. Like the Sassafras River versus the Back 
River?
    Dr. Burke. Yes.
    Mr. Gilchrest. The Back River would be worse than the 
Sassafras?
    Dr. Burke. I am not quite sure of that specific comparison.
    Mr. Gilchrest. But it would be those tidal basins----
    Dr. Burke. Yes.
    Mr. Gilchrest [continuing]. That would be of more concern 
than the main focus of the Bay?
    Dr. Burke. Yes, because of the biology of the Bay and the 
nature of the food chain of the fish.
    Mr. Gilchrest. Since fish consumption is part of the, I 
would assume, main criteria for determining how dangerous this 
is, and since probably people in Kent County, Maryland or Anne 
Arundel County don't eat as much as they do in the Seychelles, 
would not be put at that same risk. Have there been studies 
done to evaluate the neurological development of things like 
eagles and osprey and blue heron, those kinds of things?
    Dr. Burke. I am not aware of ecological studies that way. 
That was a little bit beyond the scope of the National Academy 
work.
    Mr. Gilchrest. Could you assume that there would be 
potential mercury poisoning in those animals that do eat fish 
everyday?
    Dr. Burke. Absolutely. I think that we would see the same 
kind of bioaccumulation and high level exposure to the nervous 
system.
    Mr. Gilchrest. Are you aware of any type of study that 
would look at that?
    Dr. Burke. I can get back to you on that, but----
    Mr. Gilchrest. Thank you. Thank you.
    Yes, sir?
    Dr. Krabbenhoft. There are some studies in USGS of the 
Patuxent National Wildlife Testing Center where they are 
looking at methylmercury exposure and the toxicological effects 
to methylmercury exposure at the egg level of several of the 
species that you have just named. And the short answer to your 
question is yes, there are effects. It does have an appreciable 
affect on the successful hatching rate of those birds.
    Mr. Gilchrest. Thank you.
    Mr. Colburn.
    Mr. Colburn. I was just going to reinforce that, 
Representative. There has been some work done on loon, which of 
course, eat fish, along the lines mentioned by Dr. Krabbenhoft 
in the Northeast.
    Mr. Gilchrest. Thank you very much. Thank you, Mr. 
Chairman.

                            Closing Comments

    Chairman Ehlers. Well, thank you very much for your 
questions. They have contributed to this hearing.
    With no further questions, I would like to conclude the 
hearing with several comments. I think it is clear from today's 
hearing that there is compelling evidence that consumption of 
fish contaminated with mercury is a serious health threat. I 
also think we learned that there is a local effect from 
emissions from utility sources as well as a global effect and 
that reducing emissions from these sources will likely lead to 
reduced loading in the environment.
    On the technology side, it also seems clear to me that 
while current technologies do achieve significant mercury 
reductions as a co-benefit, we have much to do to develop the 
technologies specific to mercury control. It appears that it 
may take regulation before we create a sufficient market that 
will drive innovation and commercialization of these 
technologies. Past experience, as Mr. Colburn has said, has 
certainly demonstrated that major advances in technology 
development follow regulation in many fields and often at much 
lower costs than initially projected. But we will see how this 
plays out. I assume that the EPA is likely to set a standard 
some time in the next month or two. And we will as Dr. Offen 
has pointed out, the time allotted to solve the problem could 
have a direct impact on the cost to the economy generally.
    I certainly want to thank all of you for your participation 
at the hearing today. It has been a good cross-section of 
expertise. I, frankly, think we couldn't have had a better 
panel broadly representative of the issue from the Government, 
industry, and academia. And so I appreciate not only your 
testimony but your wisdom and your willingness to sit through 
all of these questions we have thrown at you.
    If there is no objection, the record will remain open for 
additional statements from the Members. And also, Members may 
request answers from you, and we ask that you be kind enough to 
respond to any follow-up questions that the Subcommittee 
Members may send you. Without objection, so ordered.
    Thank you, again, for your service, for your testimony, and 
keep up the good work. It is my pleasure to declare the hearing 
adjourned.
    [Whereupon, at 3:44 p.m., the Subcommittee was adjourned.]
                              Appendix 1:

                              ----------                              


                 Biographies and Financial Disclosures




                     Biography for Thomas A. Burke
    Thomas A. Burke is a Professor and Associate Chair at the Johns 
Hopkins Bloomberg School of Public Health, Department of Health Policy 
and Management, with joint appointments in the Department of 
Environmental Health Sciences and the School of Medicine, Department of 
Oncology. Currently he is Director of the School's newly formed task 
force, Scientist Working to Address Terrorism (SWAT). The goals of the 
task force are to provide: 1) scientific basis for rational action; 2) 
accurate advise for public agencies and profession and 3) develop short 
training for targeted groups via web, CD-Roms, etc. He is also Co-
Director of the Johns Hopkins Risk Sciences and Public Policy 
Institute. His research interests include environmental epidemiology, 
the evaluation of community exposures to environmental pollutants, the 
assessment and communication of environmental risks, and the 
application of epidemiology and health risk assessment to public 
policy. He was Principal Investigator for the Pew Environmental Health 
Commission aimed at revitalizing the national infrastructure for 
environmental health. He is particularly interested in health and 
environment in the cities.
    Prior to his appointment at Johns Hopkins, Dr. Burke was Deputy 
Commissioner of Health for the State of New Jersey. He has also served 
as Assistant Commissioner for Occupational and Environmental Health at 
the New Jersey Department of Health, and as Director of the Office of 
Science and Research in the New Jersey Department of Environmental 
Protection. During his tenure with the State of New Jersey, Dr. Burke 
established a number of exposure research efforts and environmental 
risk assessment programs at both the Departments of Environmental 
Protection and Health. He served as the scientific coordinator for many 
of the State's major investigations, including investigations of toxic 
contaminants in drinking water, the evaluation of dioxin contamination 
from industrial sources, and the investigation of chromium exposure in 
urban areas from industrial waste used as landfill.
    Dr. Burke is the Chair of the Advisory Committee to the National 
Center for Environmental Health of the Centers for Disease Control. He 
also serves as a member of the Executive Committee of the EPA Board of 
Scientific Counselors. An editor of the book, Regulating Risk: The 
Science and Politics of Risk, he served on the National Academy of 
Sciences Committee on Risk Characterization. He has been a member of 
the Council of the Society for Risk Analysis and has served on the 
Office of Technology Assessment Advisory panels on Research on Risk 
Assessment of Chemical Carcinogens, and Managing Nuclear Materials from 
Warheads. He was also a member of National Academy of Sciences 
Committee an Risk Characterization, Panel on Separations Technology and 
Transmutation Systems, and Committee on Remediation of Buried and Tank 
Wastes, evaluating nuclear waste management options. He has served on 
EPA Science Advisory Board subcommittees, including reviews of the 
Clean Air Act Residual Risk Report to Congress and the Superfund Hazard 
Ranking System. He was also a member of the General Accounting Office 
expert panel to review the Superfund public health assessment process.
    Dr. Burke received his Ph.D. in epidemiology from the University of 
Pennsylvania, his M.P.H. from the University of Texas, and his B.S. 
from Saint Peter's College.



                   Biography for David P. Krabbenhoft

Education:

Ph.D. Geochemistry/Hydrogeology-1988
University of Wisconsin-Madison

M.S. Geochemistry-1984
University of Wisconsin-Madison

B.S. Geology-1982
North Dakota St. University

    David Krabbenhoft is a research scientist with the U.S. Geological 
Survey (USGS). He has general research interests in geochemistry and 
hydrogeology of aquatic ecosystems. Dave began working on environmental 
mercury cycling, transformations, and fluxes in aquatic ecosystems 
after completing his Ph.D. in 1988; and the topic has consumed him 
since. His work on mercury started with the Mercury in Temperate Lakes 
project in 1988, which served as the springboard for other 
environmental mercury research in the United States and around the 
world since. In 1994, Dave established the USGS's Mercury Research 
Laboratory, and since has assembled a team of multi-disciplinary 
mercury investigators in Wisconsin. The laboratory is a state-of-the-
art, analytical facility strictly dedicated to the analysis of mercury, 
with low-level speciation. In 1995, he initiated the multi-agency 
Aquatic Cycling of mercury in the Everglades (ACME) project, and in 
1998 organize and conducted a national synoptic sampling of mercury in 
sport fish, sediment and water from 122 sites across the United States 
for the USGS. More recently, Dave has been a Primary Investigator on 
the internationally conducted Mercury Experiment To Assess Atmospheric 
Loading in Canada and the United States (METAALICUS) project, which is 
a novel effort to examine the ecosystem-level response to loading an 
entire watershed with mercury. The Wisconsin Mercury Research Team is 
currently active on projects from Alaska to Florida, and from 
California to New England. Since 1990, he has authored or co-authored 
over 50 papers on mercury in the environment. In 2006, Dave will serve 
as the co-host for the 8th International Conference on Mercury as a 
Global Pollutant in Madison, Wisconsin.
                     Biography for George R. Offen
Manager, Air Emissions and Coal Combustion Product Management

Education: LB.S., Mech. Engr., Stanford University; M.S., Mech. Engr., 
MIT; Ph.D., Mech. Engr., Stanford University

Experience

EPRI (1985-present). Dr. Offen manages EPRI's R&D program to cost-
effectively reduce NOX, SO2, particulate, and air toxic 
emissions from utility boilers, as well as to increase the use of coal 
combustion products. He started EPRI's program on mercury control 
technology R&D in the late 1980's, and recently expanded it into the 
Integrated Environmental Control program. He has presented EPRI's air 
pollution control research results at numerous public meetings as well 
as to regulatory agencies, and coordinates EPRI's collaborations with 
DOE and EPA in air emission control technology. Currently, he is 
directing a study to obtain an understanding of mercury chemistry in 
the cooler temperature regions of a boiler and across catalysts used 
for NOX reduction. Earlier projects included dry sorbent furnace 
injection for SO2 control, fundamental research in 
combustion NOX formation/destruction, and analyses of NOX control 
combustion and post-combustion options in search of the least-cost 
combinations for any given site and NOX limits.

Acurex Corporation, California (1974-1985). Manager, Energy 
Engineering. Responsible for projects in combustion testing and 
performance/environmental impact analysis of alternate fuels.

Earlier. Acting Assistant Professor and Teaching Assistant in 
Mechanical Engineering; Research Engineer in petroleum industry, and 
Test Engineer for conventional munitions in U.S. Air Force.

Associations. Air & Waste Management Association; American Society of 
Mechanical Engineers.



                    Biography for Kenneth A. Colburn
    Kenneth A. (Ken) Colburn is Executive Director of the Northeast 
States for Coordinated Air Use Management (NESCAUM), a 36-year-old 
policy research and analysis organization representing state air 
quality agencies from New England, New Jersey, and New York. NESCAUM 
and its sister organization--the Northeast States Center for a Clean 
Air Future (NESCCAF)--provide technical assistance, research, and 
policy analysis to help the Northeast states develop and promote cost-
effective clean air solutions necessary to enhance the quality of life 
of their citizens. Prior to joining NESCAUM in May 2002, Ken served as 
New Hampshire's air director, helping to make New Hampshire a national 
leader in reducing air pollution, including the first ``4-Pollutant'' 
bill for power plants and the first Greenhouse Gas Emissions Reduction 
Registry. Ken also served as a member of the U.S. Delegation 
negotiating an Ozone Annex to the U.S.-Canada Air Quality Agreement and 
during G8 environmental negotiations in Japan, and testified before 
Congress on several air quality issues.
    Before joining the New Hampshire Department of Environmental 
Services (NHDES) in 1995, Ken was Vice President of the Business & 
Industry Association of New Hampshire (BIA), representing the State's 
business community on environmental, energy, and telecommunications 
matters in legislative and regulatory forums. Ken holds a B.S. in 
Mathematics from MIT and MBA and M.Ed. degrees from the University of 
New Hampshire. Ken and his family reside in Meredith, New Hampshire.

    Kenneth A. Colburn, Executive Director, NESCAUM, 129 Portland 
Street, Boston, MA 02114; (617) 367-8540 x216; Fax: (617) 742-9162; E-
mail: [email protected]





                              Appendix 2:

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                   Additional Material for the Record














































































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