The commission’s consideration of the 2010 Nitrogen Dioxide (NO2) National Ambient Air Quality Standard (NAAQS) designation recommendation has been rescheduled to the November 18, 2010, commissioners’ agenda. State designation recommendations are due from the governor to the EPA on January 22, 2011.


On February 9, 2010, the United States Environmental Protection Agency (EPA) published a final rule in the Federal Register  to strengthen the primary National Ambient Air Quality Standard (NAAQS) for nitrogen dioxide, establishing a new one-hour standard at 100 parts per billion (ppb). The new standard focuses on short-term exposures to NO2, which are generally highest on and near major roads. Currently, no area in Texas monitors above the 100 ppb standard. The EPA is retaining the current annual average NO2 standard of 53 ppb. The EPA is changing the monitoring network to capture both peak NO2 concentrations that occur near roadways and community-wide NO2 concentrations. Approximately 126 new NO2  monitoring sites will be placed near major roads in 102 urban areas nationwide. About eight new monitoring sites are anticipated in Texas and will likely include DFW, HGB, San Antonio, Austin, El Paso, and McAllen-Edinburg-Mission areas.


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