|
Our
National Parks: A Dim View
|
The wildfires burning near Yellowstone National Park this summer have not only taxed firefighters but have made the vistas at this American landmark considerably smokier. While these difficulties are temporary, many of America's parks face an ongoing battle—against air pollution. How did this pollution happen, and what are we doing about it?
Air pollution in our national parks is difficult to fathom. But in such stunning, vast places as the Grand Canyon, Yosemite National Park, Great Smoky National Park, and many of the 153 other federally protected parks in America, the air is often dirty enough to reduce the view and dangerous enough to damage species of trees, animals, fish, and amphibians.
Ironically, the very majesty of the mountains in our national parks has created perfect conditions for trapping air pollution. This pollution comes primarily from coal-burning power plants located hundreds of miles away and carried by wind currents into the hearts of the parks. And despite considerable cleanup efforts by the power plants and monitoring efforts by the federal government, the problem still persists.
|
|
|
"When it comes to unhealthy air, we've got it," says Air Resource Specialist Jim Renfro of Great Smoky National Park. Since 1948, average visibility in the Southern Appalachian mountains—where Great Smoky National Park is located—has decreased by 40% in winter and 80% in summer, according to National Park Service (NPS) reports.
-
If vistas at Great Smoky once stretched 93 miles or more, calculate how far you can see there with polluted conditions during a) winter and b) summer months.
-
With 10 million visitors annually, Great Smoky is, in spite of its unhealthy air, the most popular of all the national parks.
And yet, says Renfro and his colleagues, Great Smoky National Park also receives the highest levels of pollution from nitrate and sulfur deposits—causing acidic precipitation and ozone smog haze—of anywhere in North America.
"Even compared to Atlanta, which is the dirtiest city in the East for ozone smog, we're two times higher! Something has got to give," says Renfro. In 1998 there were 52 days when air pollution levels violated the federal health standard. According to the National Park Service (NPS), this kind of ground-level ozone can cause coughing, sinus inflammation, chest pains, even permanent lung damage and reduced immune functions.
A recent study by the Harvard School of Public Health, Brigham & Women's Hospital, and the Appalachian Mountain Club showed that even healthy hikers' respiratory function decreased when ozone levels were elevated, putting people with asthma at greater risk.
At Great Smoky, the acid deposits
have reduced the red spruce population
significantly. They have also damaged
over 30 different species of vegetation.
Although it is more difficult to pinpoint
damage to specific populations of migrating
animals and fish, laboratory research
has shown that mercury—an airborne
pollutant whose largest industrial source
is also coal-burning power plants—is
being absorbed into the muscles and tissues
of these creatures, which are also being
injured by acid rainfall.
|
|
Terms of Pollution
Acid rain: One of a number of precipitations (also sleet, snow, fog) mainly caused by the release into the atmosphere of sulfur dioxide (SO
2
) and oxides of nitrogen. Acid deposition occurs as wet precipitation (snow, sleet, rain, fog) and also as dry particles from the atmosphere absorbed directly by lakes and streams.
Ozone smog: Not to be confused with the beneficial ozone layer that filters the Sun's ultraviolet rays, this is the bad kind of ozone, a colorless gas created when nitrogen oxides (NOx) mix with hydrocarbons in the presence of sunlight. Sulfur dioxide (SO
2
) is the primary pollutant, contributing to visibility loss and regional haze.
Mercury (Hg) contamination: Once in water, mercury is converted to methyl mercury, which acts as a toxin in sufficient doses. This toxin causes health problems such as kidney failure and mental retardation in children.
|
|
|
Unhealthy air is not confined to Great Smoky. A study conducted for the National Parks and Conservation Association (NPCA) by the Colorado State University showed that most of the parks' chief stewards regarded their parks to be in only "average" condition, with some even receiving "failing" grades.
EPA studies indicate that ozone levels above 85 ppb can cause shortness of breath, reduced lung function, and may cause permanent lung damage.
In 1998, Acadia National Park in
Maine was the first place in the country
to record an ozone violation, with higher
concentrations of ozone smog than in Boston,
Massachusetts, and Philadelphia, Pennsylvania.
That same year, Shenandoah National Park
in West Virginia recorded higher concentrations
of ozone than any city in the Southeast
except Atlanta, Georgia, and Charlotte,
North Carolina. Bad air in Shenandoah
has significantly reduced visibility,
killed fish, and damaged vegetation. Park
personnel at Cadillac Mountain in Acadia
National Park post public health advisories
due to high ozone levels there. What's
going on?
|
|
|
Coal-Burning Power Plants
|
|
|
Coal-burning power plants are America's largest industrial source of acid rain, haze-producing ozone smog, and mercury pollution, according to the EPA, the Park Service, and environmental lobbyists.
Why, then, is coal the biggest source of electricity in this country? Because, according to industry spokesman John Kinsman, coal is reliable, plentiful, and affordable.
"Burning coal allows businesses to remain competitive and it keeps the cost of electricity relatively low. We believe this is important," says Kinsman, who represents the Edison Electric Institute in Washington, D.C., a private trade organization and lobbying group for the utility industry.
In 1977, older coal-burning power plants were granted an exemption from meeting federal Clean Air standards, because it seemed likely that they would be closed within a few years. But not only are these so-called "grandfathered" plants still operating today, they release four to ten times more pollution than modern coal-burning plants.
According to the EPA, these older plants are responsible for
97% of the acid rain and haze-causing sulfur dioxide;
85% of the ozone smog-causing nitrogen oxide; and
99% of the toxic mercury pollution caused by the utility sector.
-
If it costs coal plants $1,700 to reduce one ton of nitrogen oxide, as the Park Service says it does, how much will it cost these plants to reduce emissions by 5 million tons?
Pending finalization of an EPA plan, the federal government will restore our national parks to their original visibility levels by the year 2065.
|
|
|
