New Asheville City Council member Carl Mumpower was introduced to new findings that will likely surprise many of his constituents: The source of most of Asheville's ozone pollution is apparently not the TVA plants in Tennessee but Asheville's own tailpipes and smokestacks.
Mumpower, attending his first board meeting as City Council's liaison to the WNC Regional Air Quality Agency, listened intently on Jan. 14 as AQA staffer Melanie Pitrolo presented the preliminary results of the long-anticipated Southern Appalachian Mountains Initiative study of regional air quality.
"There's a little more complexity than would appear [at first]," was how Mumpower (who volunteered for the liaison post) described his impression after the board meeting. "You ask most people where's our pollution coming from, 90 out of 100 think it's all coming from Tennessee. That initial research got us all started down the wrong path."
To settle the politically volatile question of who's most to blame for the Land of the Sky's increasingly hazy atmosphere and spiraling childhood-asthma rates, WNC's air-quality experts have been awaiting SAMI's extensive data inventory and computer modeling of the sources and movements of the region's air pollution. The nearly nine-year-long project has brought together state and federal regulators, industry representatives, environmentalists, academics and members of the public to study air pollution's effects on the environment of the Southern Appalachians, and to recommend emissions-control strategies for the eight surrounding states. Although the final results aren't due out till April 1, the overall picture now emerging from the data confirms what some experts have suspected.
"I think [most] high-level ozone -- mountain-peak ozone -- is transported [from elsewhere]. But low-level [valley ozone] is generated locally," summarized AQA Director Bob Camby after Pitrolo's presentation.
SAMI's tentative findings reinforce a distinction -- which experts consider critical, but which the political debate usually overlooks -- between our forested ridge tops and our populated valleys.
The ridge tops are particularly afflicted by the haze and acid rain created in the atmosphere when water mixes with sulfur dioxide (SO2), a byproduct of the coal burned by some older power plants. The resulting sulfates are lightweight and can travel long distances on high-altitude winds. SAMI's study of the Great Smoky Mountains National Park, Joyce Kilmer National Forest, Linville Gorge and Shining Rock Wilderness found that sulfate pollutants are transported into these high-level parks from all over the Southeast. N.C. Division of Air Quality Director Paul Muller, a SAMI participant interviewed by Mountain Xpress, points out that -- although no one state contributes even half the sulfates at any of these sites -- the largest percentages of pollutants at these parks do come from Tennessee or Georgia, not from North Carolina, because most of WNC's and Eastern Tennessee's rain blows in from the west or southwest, rather than the east.
But in the valleys -- where the vast majority of WNC residents live, breathe and drive ever-increasing numbers of smog-spurting cars, trucks, lawnmowers and backhoes -- it's a different story. Here, the principal villain is nitrogen oxide (NOx), a relatively heavy, slow-moving chemical (produced by both cars and power plants) that cooks into ozone when it's trapped on a hot, still day in our inversion-prone valleys.
"[SAMI's] preliminary results suggest that changes in emissions primarily affect air quality locally/regionally," Pitrolo reported. Decreases in automobile emissions, SAMI found, have a greater impact on ozone levels than decreases in power-plant emissions. During WNC's ozone season (roughly late spring through early fall), more NOx is emitted from tailpipes than from smokestacks -- partly, AQA staffers explained, because of NOx controls installed in recent years on WNC's largest point-source polluter, the CP&L plant at Skyland, but also because of the significant growth in total vehicle miles traveled.
Though not based on measurements specific to Asheville, these findings do support Camby's assertion that low-level ozone is mostly generated locally, confirmed U.S. Forest Service air-quality expert Bill Jackson, another SAMI participant. Because of the density of NOx, added Jackson, ozone tends to form within a range of no more than 60 miles from the source of the emissions that generate it.
"What we're learning is ... that what we do here affects us here," observed Asheville board appointee Nelda Holder at the meeting. "We can never neglect the fact that we sit in a bowl, and we create our own stew."
"Until recently," Mumpower questioned the board, "the indications were that the pollution was coming from the west. Was that flawed research?"
No, answered Camby. Rather, it's a widespread misunderstanding of a statement Dr. Robert Bruck of N.C. State University made on the air agency's popular educational video, A Prayer for the Mountains. Bruck conducted a 20-year study of acid rain on Mount Mitchell.
"He's the one who said acid rain affecting Mount Mitchell and Grandfather Mountain was 80 percent transported in from other regions," noted Camby. "And I think it's true -- for that area. When you get down below 4,000 feet, then you have other causes. His statement was mistaken by a lot of people to mean that all the pollution was coming in here, and that most of it was somebody else's problem."
Surprisingly, the much-maligned Tennessee Valley Authority has cleaned up its power plants' emissions to the point that Tennessee is now producing less SO2 than North Carolina, whose SO2 emissions have remained essentially unchanged over the past 20 years (see chart).
"Does that mean you will give up your work on trying to get the TVA to clean up?" asked Mike Plemmons, director of the Council of Independent Business Owners, who sat next to Mumpower, whispering in his ear through most of the meeting. In Buncombe County, CIBO leaders have been among the most vocal opponents of attempts to regulate homegrown air pollution (which, they worry, could hamper development and business growth without significantly lessening air pollution). "Is the SAMI study gospel now, or is it just one among many studies?"
The answer, according to both Camby and Muller, is that SAMI's conclusions are still tentative. Because the study's goal was to measure the environmental effects of air pollution, not the health effects, SAMI did not focus its computer modeling directly on Asheville or the other valley towns of WNC. And until the state or the AQA can pay Georgia Tech (where the modeling studies are being done) to run SAMI's data through a geographic-sensitivity analysis, no one can say exactly what percentage of our low-level pollution is local and how much is transported -- either to here from elsewhere or from here to other states.
But there is one thing the data do clearly show, says Jackson: "It's really important for us to continue to emphasize that we need to work regionally to solve the problems. ... We [in the SAMI states] need to work together."
"We spend too much time trying to figure, is it this or that," AQA board Chairman Alan McKenzie stated at the meeting. "It is this and that.
"I think also we're going to have to have the political will to say we want to improve," said McKenzie. "We often talk about the cost of cleaning up, but we never talk about the cost of not cleaning up."
Perhaps that will to improve will strengthen as the causes and consequences of WNC's air pollution become better known. One politician, at least, says he wants to learn more.
"It's my intention to come to all the meetings," Mumpower promised the board when he was introduced. "I want to try to be useful in that liaison role with City Council. I like to be helpful; I don't like to make things harder."
Pullquote:"We often talk about the cost of cleaning up, but we never talk about the cost of not cleaning up."
-- WNC Air Quality Agency board Chairman Alan McKenzie
U.S. Forest Service air-quality specialist Bill Jackson will discuss the preliminary SAMI results in a free public presentation at noon on Wednesday, Jan. 23 at St. Mark's Lutheran Church in downtown Asheville (off Merrimon Avenue at the corner of East Chestnut and Liberty streets).