By SALLIE SATTERTHWAITE
Staff Writer

With a sense of innocence lost, Fayette County citizens are learning that they can no longer think of their mostly-rural county as distant and thus removed from Atlanta's air quality problem.

They are a documented part of the problem. Or, in the immortal words of Walt Kelly's Pogo, "We have met the enemy and he is us."

Last fall, the Air Protection Branch of Georgia's Environmental Protection Division installed an air quality monitoring device in Fayette County on McDonough Road off Ga. Highway 54 east of Fayetteville. The site, opposite McCurry Park and at the Georgia Department of Transportation maintenance shop, was chosen for its openness and distance from tall trees and buildings.

Equipment there has revealed that on several occasions since monitoring began in April, Fayette's ozone levels have been the highest in the metro area.

Information gathered in Fayette and pooled with that collected at seven other sites indicates that by early August 1998, Atlanta had already exceeded ozone level standards more frequently than during the entire hot-weather season last year.

Kenneth Powell, a meteorologist with the air protection branch, recently led a reporter and a photographer through the facility and explained how it works.

Its mission, in the simplest terms, is to report ozone levels in the air around the McDonough Road site. Those, combined with other air quality factors and similar reports from the entire metro area, generate the daily pollutant standards index (PSI) published by the state.

Announcements caution the public when health hazards exist and encourage citizens and manufacturers to take steps to reduce the pollution in Atlanta's air. For many people, Powell said, ozone is the most confusing component of Earth's atmosphere.

On the one hand, in the stratosphere six to 30 miles above the ground, ozone is vitally important to shield the planet from harmful ultraviolet radiation. This is the layer that scientists caution is being destroyed by chlorofluorocarbons.

But at ground level, ozone is a major component of smog which damages vegetation, humans and animals, and the surface of buildings and statues. It is a health hazard of particular danger to the very young, the elderly, and those with already-compromised respiratory systems.

The federal Environmental Protection Agency has devised a PSI scale that ranges from "good" (below 100) through "moderate" and "unhealthful" to 400, which would constitute emergency conditions requiring severe curtailment of most industrial, commercial, and vehicular activity.

"The Fayetteville site is a very important part of the entire network," Powell said. "We retrieve data from the site at least daily. Every hour we get ozone data, 24 hours a day [by a telephone link].

"The data goes into the overall air quality index. There have been several days when the Fayetteville site has had the highest ozone levels in metro Atlanta."

From the outside, the little structure eight feet wide, eight feet high, and 12 feet long resembles nothing so much as a large meat locker, its walk-in door padlocked, its side and flat roof studded with sensing devices, a lightning rod projecting from the top.

"The wind equipment turns to give wind direction, and the propeller indicates air speed," Powell said. "Lightning rods have saved our equipment more than once," he added.

A device resembling a miniature shower head is actually a stainless steel funnel, and extends exactly 10 meters above the ground, the standard of World Meteorological Organization for height.

This position allows the equipment to draw from an unobstructed air flow, providing "a true representation of ozone in the air to the inside analysis equipment," Powell explained.

"The equipment meeds to be in a climate-controlled environment," he continued, entering the little building. "So we have specialized thermostats that turn on air conditioning or heat it's very delicate. And someone comes down and does an instrument check once a week."

The analyzer is "flushed" with pure air, or "zero air" as Powell calls it, to establish the baseline, then "challenged" with a known concentration "high enough to indicate that people are dying on the street," the upper range of the analyzer's capability. The system is purged again and normal tests resume.

On the monitor's screen, Powell exhibited a typical 24-hour day from July. The tracing in 1-minute averages linked together begins at about 6 a.m., normally the low point of each day, before the rising sun has begun to warm the atmosphere, turning volatile organic emissions and nitrogen oxides into ozone.

As the day progresses, the line gradually begins to rise on the screen indicating ozone increases. Between 3 and 5 p.m., it levels out briefly at a reading of .124 parts per million of ozone in the ambient atmosphere.

Powell said .125 ppm is the 1-hour standard. "Under .125 means we're not in trouble yet.

"But as soon as our neck of the woods receives UV radiation, a chemical action begins. Here you see that on this date in July, at the Fayetteville site, it peaks for a couple of minutes, above .124, about 5 p.m."

From that point on, the line decreases very erratically over the next few hours. "That may indicate late afternoon thunderstorms," Powell said.

As the nighttime hours pass, the tracing drops more gradually until it bottoms out about 5 a.m. Shortly after sunrise the next morning, around 6 a.m., the line begins its climb, recording the next day's ozone generation.

As for the occasional area-high readings at the Fayetteville monitoring site, Powell did cut Fayette County a little slack: "Normally when the wind is from the north, Fayette County gets its highest ozone readings," he said. Atlanta and its concentration of freeways and manufacturing sites, is north of Fayette. The prevailing winds are westerly or from the northwest, Powell said.

The air protection division monitors air pollution throughout the Atlanta region on a line stretching from northwest to southeast, he continued, with a total of eight sites at present.

They are in Yorkville in western Paulding County in Douglasville near Grant Park, "at the eastern edge of the urban area of Atlanta," on the campus of South DeKalb College, in a pasture of the Monastery of the Holy Spirit in Conyers, in Fayetteville, in Tucker, North DeKalb County, and at the Gwinnett Technical Institute in Lawrenceville.

A meat locker-like monitoring facility at a monastery? "It's hidden away on pasture land, flat and with not too many trees," Powell said. "The monks have been generous to us."

Powell said four more sites will be in operation by spring of next year, ready for the April 1-Sept. 30 monitoring period. Their exact locations have not yet been determined.

"There are 13 counties in the non-attainment area," he said, referring in governmentese to the region defined by the EPA as failing to meet air quality standards. "Eventually each will have its own monitor."

Powell was a meteorologist in the U.S. Air Force, where he did air quality modeling. He's been with the state air protection division nearly 16 years.