Air Trends
Lead (Pb) Air Quality Data Update
2005-2006 Design Values
The following is a brief summary of EPA's 2006 air quality update for lead (Pb)
based on ambient monitoring data for the two year period, 2005-2006. During this two
year period:
- The Herculaneum, Missouri Pb nonattainment area violated the NAAQS for 2005-2006. The maximum quarterly average for the area for 2005-2006 is 1.93 μg/m3.
- No data were available for the other remaining designated Pb nonattainment area of the East Helena Area portion of Lewis and Clark Counties, Montana. The source associated with the East Helena area closed in early 2001 and monitoring ceased in late 2001. The latest available quarters of data (from 2001) were below the NAAQS level.
EPA's National Ambient Air Quality Standard for lead is 1.5 micrograms per cubic meter (μg/m3) maximum quarterly average. The Pb standard is not met at a monitoring site if the maximum quarterly average for the two most recent calendar years of monitoring data exceeds 1.5 μg/m3.
Air quality data from EPA’s Air Quality System (AQS) were used to calculate lead design values. The data used for these calculations were obtained from AQS on July 11, 2007. To date, no regulatory decisions on attainment status have been made for any area based on these specific calculations.
For information concerning these data, contact:
Mark Schmidt
U.S. Environmental Protection Agency
Air Quality Analysis Group (C304-01)
Research Triangle Park, NC 27711
(919) 541-2416, (919) 541-3613 (FAX)
Schmidt.mark@epa.gov