RALEIGH, North Carolina, October 5, 2009 (ENS) РNorth Carolina’s smog levels this year are the lowest since the state began monitoring air quality in the 1970s, due to weather patterns and declining emissions from industry and motor vehicles, according to data compiled by the state Division of Air Quality and made public today.

Through September 30, the end of the ozone forecast season, North Carolina had only six days in 2009 when ozone levels exceeded the eight-hour standard of 0.075 parts per million.

The previous lowest year was 2004, when 27 days exceeded the same standard for ozone levels.

Since 2000, there have been an average of 51 days per year when the ozone levels exceeded the standard.

“We are encouraged by the drop in ozone levels,” said Keith Overcash, director of the Division of Air Quality. “North Carolina has strong air quality initiatives in place, but there is still more to do. Citizens are also helping by taking actions to reduce air pollution, such as driving less, carpooling and conserving energy.”

Ozone levels have declined substantially across North Carolina during the past decade, due in part to lower emissions from coal-fired power plants, other industry and motor vehicles, says Overcash.

From 1999 to 2008, annual ozone-forming emissions from North Carolina power plants declined by 73 percent – from 201,428 tons to 54,398 tons – state data shows.

Estimated annual emissions from cars, trucks and other mobile sources declined 38 percent from 2002 to 2009 – from 327,239 tons to 201,609 tons.

Ozone, a reactive form of oxygen, is unhealthy to breathe and damages trees and crops. It is most prevalent in the summer months, when pollutants react in the air on hot, sunny days with little wind.

North Carolina typically has more high ozone days in hot, dry summers and fewer bad days in cool, wet summers. This summer was cooler but drier than normal across most of the state.

Contributing to the decline in high-ozone days are state and federal actions to reduce ozone-forming emissions from power plants, other industry and motor vehicles.

The North Carolina Clean Smokestacks Act of 2002, for instance, required the state’s 14 coal-fired power plants to cut by three-fourths their emissions of ozone, haze and particle-forming emissions by the end of 2012.

Rules adopted in 2000 by the state Environmental Management Commission, as mandated by the U.S. Environmental Protection Agency, required a two-thirds reduction in ozone-forming emissions by 2006.

State legislation expanded the motor vehicle emissions testing program from North Carolina’s nine most urban counties to 48 counties by 2006.

Stricter federal and state standards were adopted for gasoline and diesel engines in new cars, trucks and construction equipment.

Federal requirements for cleaner-burning, low-sulfur gasoline and diesel fuel took effect in 2006.

The Division of Air Quality and local media issue air quality forecasts for the Asheville, Charlotte, Fayetteville, Hickory, Rocky Mount, the Triad and the Triangle metro areas.

Ozone forecasts are issued daily from April through September, when ozone levels are highest, and year-round for particle pollution. The forecasts enable residents to take precautions on bad air days and take actions to help reduce air pollution.

Areas not meeting the ozone standard are periodically classified as “non-attainment” by the EPA.

The Division of Air Quality must develop plans for improving air quality in non-attainment areas, and such areas can face tighter restrictions on industrial emissions and additional reviews for new highway projects.

Under the ozone standard that EPA adopted in 2008, North Carolina has about 40 counties that could potentially be designated as non-attainment. The EPA had planned to designate new non-attainment areas in March 2010, but has postponed that decision pending the possible adoption of a more stringent ozone standard.

Copyright Environment News Service (ENS) 2009. All rights reserved.