June 2004 State Government Lies, Damned Lies & Air Quality Statistics By Steve Tuttle The EPA’s recent determination that ozone levels are unacceptably high in North Carolina’s three metro areas – and in some rural counties as well – again raises the question of whether it’s OK to breathe the Tar Heel air. Who wouldn’t heave a confused sigh after reading, in the space of one week, that the American Lung Association had rated Charlotte, the Triangle and the Triad as among the 25 smoggiest places in America even as the state was receiving a federal Clean Air Excellence Award for reducing emissions from coal-fired power plants. The EPA itself seems to be adding to the confusion. Its press release announcing that ozone levels in 26 counties in North Carolina and parts of six others now violate the Clean Air Act came with extensive background materials. One was a briefing paper revealing that Charlotte had only four days of unhealthy air in 2003 compared to 39 in 1980, a 90 percent improvement, and that the Triad had only two days of unhealthy air in 2003 compared to 14 in 1980, an 86 percent improvement.

BAD AIR DAYS Nonattainment counties on EPA's new 0.08 ppm eight-hour ozone standard  Charlotte Region: Moderate ozone levels (more than 0.121 parts per million) found in Gaston, Mecklenburg, Cabarrus, Iredell (part), Lincoln, Rowan and Union counties. Must submit correction plan by June 2010. Triad Region: Moderate ozone levels in Davidson, Davie, Forsyth, Guilford, Alamance, Caswell, Randolph and Rockingham counties. Must prepare correction plan by December 2007. Triangle Region: Basic ozone levels (less than 0.121 parts per million) in Durham, Granville, Wake, Chatham (part), Franklin, Johnston, Orange and Person counties. Must submit correction plan by June 2009. Hickory Region: Basic ozone levels in Alexander, Burke (part), Caldwell (part) and Catawba counties. Must submit correction plan by. December 2007. Great Smoky Mountains: Basic ozone levels found in Haywood (part) and Swain (part) counties. Must submit correction plan by June 2009. Fayetteville: Basic ozone levels found in Cumberland County. Must submit correction plan by December 2007. Rocky Mount: Basic ozone levels found in Edgecomb and Nash counties. Must submit correction plan by June 2009.

Amid these conflicting signals, the fact remains that large companies building or expanding in the counties now deemed to violate ozone rules (see chart) may be required to install state-of-the-art emission control equipment to comply with stricter controls being formulated by state and local authorities. While EPA officials insist that none of the regions that violate the new ozone rules will be required to curb business growth or lose federal highway funds, state  and local officials say the bad-air label is a perceptual black eye that will make it more difficult to keep existing businesses and attract new ones.

The perplexing gulf between the differing assessments of our air quality can only be explained in light of British statesman Benjamin Disraeli’s observation that there are three kinds of lies: lies, damned lies and statistics. When it comes to assessing air quality, it seems, everyone cites their own statistics. The important thing is to pay attention to what, when and especially how the numbers were crunched.

What’s being measured influences the result: Charlotte — despite its 90 percent fewer bad air days than a generation ago — does violates the Clean Air Act today because the feds have dramatically tightened their standards. Air quality is determined by monitoring stations positioned around the state that “sniff” the air to measure ozone, the principal cause of smog, and other pollutants. Until recently, the standard for ozone was less than 0.12 parts per million detected during a one-hour-long “sniff” of the air. Beginning this year, the monitoring stations began sniffing the air for eight-hour stretches at a time and set off alarm bells if they record as little as 0.08 parts per million of ozone during that time.

When statistics are taken can be important. In concluding that more than half of all North Carolinians breathe dirty air, the American Long Association relied on statistics from the summer of 2002 when the state was suffering through an historic drought. The drought produced stale, stagnant air masses that trapped high ozone levels over the state for weeks at a time. The drought of 2002 was followed by the unusually wet summer of 2003. Frequent rains tend to wash ozone out of the air, which explains why the EPA recorded only four bad-air days in Charlotte that year and two in the Triad.

How the data is compiled can be confusing. Is the air dirtier in North Carolina than in other states, or are we just more aggressive in looking for it? The state Department of Environment and Natural Resources maintains 128 air quality monitoring stations in more than 30 counties, far more than most other states. Most are in urban areas but some are located in surprisingly out-of-the-way locales, such as the one in Leggett, a town of 75 residents between Rocky Mount and Tarboro. Because the Leggett station recorded one instance of high ozone last year, Edgecombe and Nash counties now must comply with EPA’s new rules even though the ozone recorded by the Leggett station probably blew in from Raleigh.

Then there’s the curious case of the air monitoring station on South Salisbury Street in Lexington, which for the past three years has been recording unusually high levels of fine airborne pollutants. It was data from this one station that caused Davidson County to be listed among the counties with bad air. Local officials retained Raleigh environmental law specialist Alan McConnell to fight the designation, and he reached a novel conclusion: The station’s “nose” was being confused by the aroma wafting from Lexington’s 23 barbecue joints.

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