    Air Pollution: Air Quality and Respiratory Problems in and Near
    the Great Smoky Mountains (25-MAY-01, GAO-01-790T).

    Concerns have been growing about the air quality, visibility, and
    respiratory illnesses around the Great Smoky Mountains National
    Park, which straddles the border between North Carolina and
    Tennessee. This testimony analyzes recent trends in and
    contributing factors to (1) visibility impairments, (2)
    ground-level ozone, and (3) respiratory illnesses. This testimony
    also examines the Tennessee Valley Authority's (TVA) plans to
    reduce its emission of regulated pollutants from generating
    electricity. Visibility impairments and ozone are largely
    attributable to the following three types of emissions: sulfur
    dioxide, nitrogen oxides, and volatile organic compounds. The
    counties that border the park generally have slightly higher
    mortality rates from two types of respiratory illness. The three
    types of emissions interact in the atmosphere to form ozone gas
    and sulfate particles, which are linked to respiratory illnesses.
    In response to federal laws and other factors, TVA is making
    substantial environment-related investments and expects to reduce
    its annual emissions of sulfur dioxide by 36 percent and its
    ''ozone-season'' emissions of nitrogen oxides by 68 percent
    between 1999 and 2005. This testimony summarizes the May report,
    GAO-01-658.
    -------------------------Indexing Terms-------------------------
    REPORTNUM:   GAO-01-790T
        ACCNO:   A01063
      TITLE:     Air Pollution: Air Quality and Respiratory Problems in
                 and Near the Great Smoky Mountains
         DATE:   05/25/2001
      SUBJECT:   Air pollution control
    	     Respiratory diseases
    	     Electric power generation
    	     National parks
    	     Environmental monitoring
    	     Great Smoky Mountains National Park
    	     North Carolina
    	     Tennessee

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    GAO-01-790T

    Testimony Before the Subcommittee on Legislative, Committee on
    Appropriations, House of Representatives

    United States General Accounting Office

    GAO For Release on Delivery Expected at 2: 00 p. m., Friday, May 25, 2001
    AIR POLLUTION

    Air Quality and Respiratory Problems in and Near the Great Smoky Mountains

    Statement of David M. Walker Comptroller General of the United States

    GAO- 01- 790T

    Page 1 GAO- 01- 790T

    Mr. Chairman and Members of the Subcommittee: Good afternoon. It is a
    pleasure to be here in beautiful Asheville today to speak with you about the
    air we breathe. Western North Carolina has a well- justified reputation for
    beautiful mountains and diverse species of plants and animals. But air
    quality remains a concern.

    For about the past 6 months, we have been working with Chairman Charles H.
    Taylor on a study of air quality in this area. Today, we are releasing the
    results of that study. 1 But, before we get into the results, let me tell
    you a little bit about who we are. As the Comptroller General, I head the U.
    S. General Accounting Office or GAO. GAO is part of the legislative branch
    of government, and we help the Members of Congress carry out their
    constitutional responsibilities. We perform audits, investigations,
    evaluations, and policy analyses, and we provide a range of legal services
    that span the entire scope and reach of the federal government- from Social
    Security issues to national security issues. Simply stated, our mission is
    to help the Congress make government work better for all Americans.

    For the purposes of our study of air quality in and near Great Smoky
    Mountains National Park, we were charged with answering four questions: (1)
    What is the trend in visibility in the park and what are the causes of
    reduced visibility? It is difficult to appreciate the beauty of the
    mountains if we cannot see them. (2) What is the trend in ozone in the park
    and what are its causes? Ozone, specifically ground- level ozone, is a
    potential threat to human health, (3) What is the trend in lung diseases for
    the people who live in the North Carolina and Tennessee counties that border
    the park? and (4) What are the plans of the Tennessee Valley Authority
    (TVA), the largest electric utility in this area, to reduce its emissions of
    two key air pollutants? In developing the information for our study, we
    collected data from five federal agencies- the Environmental Protection
    Agency, the Forest Service, the National Park Service, Department of Health
    and Human Services, and the Tennessee Valley Authority. In addition, we
    gathered information from state agencies in North Carolina and Tennessee,
    and from other academic, research, and special interest groups.

    1 Air Pollution: Air Quality and Respiratory Problems in and Near the Great
    Smoky Mountains (GAO- 01- 658, May 25, 2001).

    Page 2 GAO- 01- 790T

    To put our study results in context, some background on Great Smoky
    Mountains National Park and air quality is probably in order. The park
    encompasses 800 square miles in North Carolina and Tennessee. Designated a
    national park in 1934, it is 95 percent forested, and elevations in the park
    extend from 800 to more than 6,600 feet.

    Areas adjacent to the park are growing in population and economic activity.
    Between 1990 and 2000, the nation?s population grew 13 percent. During this
    same period, North Carolina?s population grew 21 percent, and Buncombe
    County- the most populous county in Western North Carolina- grew 18 percent.
    Moreover, over the past 10 years, annual recreational and non- recreational
    visits to Smoky Mountains National Park have increased from 18 million to 21
    million visitors. Unfortunately, this growth has a cost. More people usually
    mean higher demand for electricity, more cars, and more goods transported by
    truck.

    Burning coal to generate electricity and burning gasoline to power our cars
    and trucks results in emissions of many gases that can harm the environment.
    This isn?t going to be Chemistry 101, but understanding two chemicals is
    particularly important to our air quality discussion today. First, sulfur
    dioxide (SO2)- which is generated mostly from coal- fired plants located to
    the north and west of the park- is closely associated with decreased
    visibility. Second, nitrogen oxides (NOx)- which come primarily from motor
    vehicles, but also from power plants- are linked to the formation of
    potentially health- threatening ozone. Now, for the specifics of our study.
    Study Background

    Page 3 GAO- 01- 790T

    Our first question related to visibility trends in the park and the causes
    of reduced visibility. In general, visibility was poor at the beginning of
    the 1990s and remained poor through 1999 (the latest data available),
    according to the National Park Service. For the days with the worst
    visibility (those ranked in the bottom one- fifth of all days for each
    year), visibility ranged from between 12 and 15 miles during that decade.
    Visibility

    1

    Visibility in the Park on the Worst Days Remained Poor During the 1990s

    Source: National Park Service Visibility

    Page 4 GAO- 01- 790T

    On the best- visibility days in the park, visibility averaged around 51
    miles during the 1990s. By contrast, it is estimated that typical visibility
    in the park- before industrialization- was on the order of 60 to 90 miles.
    In analyzing visibility, we focused on the worst days- typically hot, humid
    summer days- because it is on those days that reduced visibility is the most
    detrimental to enjoyment of the park.

    Reduced visibility is caused by small particles in the air that either
    scatter or absorb light. In the Eastern United States generally, and the
    park specifically, most of these particles are sulfates. These particles are
    widely believed to have adverse health effects, and research is underway to
    more clearly understand how they harm health and which particles are most
    harmful.

    Sulfate particles are formed in the air from emissions of sulfur dioxide
    gas. Electric utility power plants produce about two- thirds of the nation?s
    sulfur dioxide emissions.

    Page 5 GAO- 01- 790T

    In fact, dozens of power plants are located within the states surrounding
    the park.

    2

    Electric Utilities Produce Two- Thirds of National Sulfur Dioxide Emissions

    Source: EPA Visibility

    Page 6 GAO- 01- 790T

    We know that many power plants are located in the states near the park, but
    what do we know about the sources of the sulfates reaching the park?
    National Park Service analysts recently traced the paths of the air masses
    that delivered sulfate particles to the park for the 3 days before they
    reached the park. Their analysis covered May through September in the years
    1995 through 1999.

    3

    Many Power Plants Are Close to the Park

    Source: EPA Visibility

    Note: Purple denotes power plants that became subject to new Clean Air Act
    requirements beginning in 1995. Blue denotes power plants that became
    subject to these requirements in 2000.

    Page 7 GAO- 01- 790T

    The analysts found that on low- visibility days (that is, days with high
    levels of particles), the air masses generally started their 3- day journey
    just a few hundred miles from the park and often followed a roundabout
    trajectory to get there. The majority of the air masses started over the
    industrial Midwest, or spent considerable time there, where they could have
    accumulated substantial quantities of sulfur dioxide from this highemissions
    area. A significant minority of high- sulfur air masses arrived from west of
    the park. Few air masses arrived from the east and south on these low-
    visibility days.

    Our second question related to the trend in ozone levels in the park and its
    causes. Ozone is considered a potential threat to human health, and the
    Environmental Protection Agency has established a public health standard for
    the concentration of ozone in the air that we breathe. In addition, exposure
    to ozone can harm plants, although this was not the focus of our study.

    Ozone is not emitted. It is formed from nitrogen oxides and volatile organic
    compounds in reactions initiated by sunlight. Heat accelerates the chemical
    processes through which ozone is formed.

    We concentrated on days when the ozone level in the park exceeded the
    federal standard- the standard which is also used by the state of North
    Carolina. An ?exceedance? is recorded on any day when a monitor measures
    ozone levels that exceed this threshold. The number of

    ?exceedances? in the park varied greatly during the decade. Ozone

    Page 8 GAO- 01- 790T

    During the early 1990s, the number of exceedances in the park gradually
    rose- to 8 days in 1996. Then there was a strong rise in the number of
    exceedances to 37 in 1999. Last year, the number fell sharply to 12 days.
    This decline is believed to be related to last summer?s cooler temperatures.

    4

    Exceedances of the Ozone Standard in the Park Increased in the 1990s, but
    Fell Sharply in 2000

    Ozone Source: National Park Service for Great Smoky Mountains and Shenandoah
    for 1999 and 2000; otherwise, EPA

    Note: Data for Great Smoky Mountains National Park are for Look Rock

    Page 9 GAO- 01- 790T

    The two chemicals involved in forming ozone stem from diverse sources. More
    than 50 percent of the nation?s nitrogen oxides are produced by the
    transportation sector- including cars, trucks, farm equipment- and even your
    gas- powered lawn mower. Nearly another 25 percent come from the electric
    utility sector.

    Volatile organic compounds come from both natural and human sources. Trees
    release isoprene- the most important natural organic compound for

    5

    The Transportation Sector Produces Over Half of National Nitrogen Oxide
    Emissions

    Ozone Source: EPA

    Page 10 GAO- 01- 790T

    producing ozone in this area- and North Carolina and the other heavily
    forested southeastern states are particularly rich in isoprene. Human
    sources of volatile organic compounds include the wide variety of
    hydrocarbons that result both from fuel evaporating from cars and trucks and
    from incompletely burned fuel.

    According to a recent National Park Service analysis, on high- ozone days,
    most of the air masses reaching the park arrived from the north and
    northwest- generally from the industrial Midwest. Fewer air masses arrived
    from the west and the south, and very few arrived from the east.

    Our third question related to respiratory health in the areas surrounding
    the park. We made three choices to keep our analysis manageable:

     First, of the many indicators of health conditions, such as
    hospitalizations, illnesses, and deaths, we chose to focus on deaths
    because, of all the indicators, only mortality data are available at the
    county level.

     Second, of the various specific health conditions we could have chosen to
    analyze, we chose two groups of respiratory illnesses because they have most
    often been linked to air quality. The two groups are pneumonia/ influenza
    and chronic obstructive pulmonary disease (which we will refer to as chronic
    lung disease), a term that includes asthma, bronchitis, emphysema, and other
    chronic lung diseases.

     Third, to specify the areas of North Carolina and Tennessee that are
    adjacent to the park, we chose the groupings already used by those states.
    Thus, we used the definition of North Carolina?s Department of Environment
    and Natural Resources for the 19 counties that we label Western North
    Carolina and Tennessee?s Department of Environment and Conservation
    definition for the 16 counties that we label Eastern Tennessee.

    We completed several sets of comparisons, and I?ll highlight three of them
    for you. First, we compared overall death rates for the period from 1991 to
    1998 in the states of North Carolina and Tennessee with the overall death
    rate in the United States as a whole. We found that the rates in each state
    were somewhat higher than the national rate.

    Second, we compared death rates in Western North Carolina and Eastern
    Tennessee against the comparable rates in each state. For overall deaths, we
    found that Western North Carolina and Eastern Tennessee had substantially
    lower rates than their respective states, for the period 1991 through 1998.
    Respiratory Illnesses

    Page 11 GAO- 01- 790T

    Third, for deaths from respiratory illnesses during the same period, we
    found that these two regions had slightly higher rates than their respective
    states.

    6

    Death Rates for All Causes Were Lower in Areas Adjacent to the Park Than in
    Those States as a Whole

    Note: Differences in death rates are statistically significant Source: GAO
    analysis of unpublished North Carolina and Tennessee data Respiratory
    Illnesses

    Page 12 GAO- 01- 790T

    Many factors influence the development and severity of respiratory
    illnesses, including smoking behavior and exposure to pollutants or
    allergens. Research is currently ongoing to increase our understanding of
    the link between exposure to air pollution and respiratory illnesses.

    7

    Death Rates for Chronic Lung Disease Increased in North Carolina and
    Tennessee Between 1991 and 1998

    Note: Differences in death rates are statistically significant Source: GAO
    analysis of unpublished North Carolina and Tennessee data Respiratory
    Illnesses

    Page 13 GAO- 01- 790T

    Our fourth question related to TVA?s plans to reduce its emissions of two
    key air pollutants. As you know, TVA is the largest electric utility in the
    southeast, serving customers in seven states, including some in North
    Carolina.

    Like other electric utilities, TVA is subject to a range of federal and
    state laws and regulations. Of particular significance- for TVA and all
    other utilities that burn coal to generate electricity- is Title IV of the
    1990 amendments to the Clean Air Act.

    These amendments mandated substantial reductions in emissions of sulfur
    dioxide (which is linked to reduced visibility, as I discussed earlier) and
    modest reductions in emissions of nitrogen oxides (which is linked to ozone,
    as I also discussed).

    To generate electricity, TVA relies primarily on burning coal- which
    accounted for 62 percent of TVA?s total generation over the last 5 years.
    The remaining electricity was generated by nuclear power (28 percent),
    hydroelectric power (9 percent), and other sources (1 percent).

    TVA?s total generation of electricity grew about 10 percent between 1992 and
    1999. During that period, TVA?s consumption of coal increased 18 percent.
    TVA estimates that the generation trend will continue, with peak generating
    capacity requirements expected to grow 1.7 percent per year between 1999 and
    2010. This is equivalent of adding one new average- sized power plant every
    year. To meet this challenge, TVA plans to use a combination of strategies,
    such as purchasing power, constructing new plants, and providing incentives
    to customers to reduce their peak demand.

    TVA?s total emissions of sulfur dioxide declined 30 percent between 1989 and
    1999. TVA estimates that, as a result of additional steps underway and being
    planned for the next decade, these emissions will decline an additional 36
    percent between 1999 and 2005. Mr. Chairman, your proposed legislation would
    require a substantially greater reduction in sulfur dioxide emissions by
    2005, as shown in the chart. TVA?s Plans to Reduce

    Its Emissions

    Page 14 GAO- 01- 790T

    TVA has taken and plans to take to a number of steps to reduce these
    emissions. For example,

     TVA will continue to burn coals with lower sulfur content at 51 of its 59
    units and

     TVA has installed equipment called ?scrubbers? at its three largest
    plants.

    8

    TVA Cut Its Sulfur Dioxide Emissions During the 1990s and Expects to Cut
    More by 2005

    Source: TVA TVA?s Emissions

    Page 15 GAO- 01- 790T

    Scrubbers can remove more than 90 percent of the sulfur dioxide from a
    plant?s emissions and are considered the best currently available technology
    for reducing such emissions.

    In looking at TVA?s emissions of nitrogen oxides, we focused on the 5- month
    ?ozone season? (May through September) when ozone levels tend to be
    relatively high and when exceedances tend to occur. TVA?s total nitrogen
    oxide emissions in the 1999 ozone season were about the same as in the 1989
    season. TVA projects that its ozone season emissions will decline about 68
    percent between 1999 and 2005.

    This reduction reflects, among other things, the results of TVA?s plans,
    announced in 1998, to invest nearly $1 billion in pollution- control
    equipment. Such equipment includes ?selective catalytic reduction? devices
    for nearly one- half of its coal- fired units. These devices transform
    nitrogen oxide emissions into harmless nitrogen and water vapor. Again, Mr.
    Chairman, your bill would require a substantial reduction of nitrogen oxides
    from TVA?s current projections for the year 2005.

    Page 16 GAO- 01- 790T

    In summary, let me just say that you should be commended for your concern
    about the quality of your air, and for wanting to do something about it.
    Many Americans in other areas of the country share your concern. The
    solutions to air pollution, however, are not simple. Balancing our ever-
    increasing demand for energy with our need to protect the environment for
    future generations is at the heart of the policy debates now raging in the
    Congress. We at GAO will continue to work with the Congress to help find
    solutions for this complex problem.

    9

    TVA Expects to Cut Its ?Ozone- Season? Emissions of Nitrogen Oxides Sharply
    by 2005

    Note: The ozone season is May 1 to September 30 Source: TVA TVA?s Emissions

    Page 17 GAO- 01- 790T

    That concludes my prepared statement, Mr. Chairman. I would be happy to
    address your questions.

    (360099)
    *** End of document. ***