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  • Summer ozone season ends violation free

    Oct 03, 2016 | Read More News
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    All the data has been analyzed and the results are in!  Pima County Department of Environmental Quality has determined that our region made it through the 2016 ground-level ozone season without violating the new U.S. Environmental Protection Agency’s (EPA) ozone air quality health standard.
    Ozone Monthly Averages Page 1Ozone levels are elevated in Pima County from May through September when solar radiation is the strongest. Ground-level ozone is an air pollutant that is formed by various emissions combining together in the presence of sunlight. Because studies indicated that ozone harms our health at levels lower than previously believed, the EPA strengthened the standard in October of 2015 from 75 parts per billion (ppb) to 70 ppb. According to PDEQ, the ozone levels in Pima County are at 68 ppb, which is just barely below that new more protective health standard.
    “We had a couple of days at the beginning of the summer when ozone levels were elevated, but fortunately, not high enough to be a violation of the new standard,” said Beth Gorman, PDEQ Senior Program Manager. “We are grateful to all the businesses and residents who reduced driving, engine idling, and other sources of ozone-forming emissions because these actions helped to keep us below the health standard this summer.” 
    Ozone Levels“Since ozone levels are so close to the EPA standard, continued vigilance is key to maintaining compliance with the standard,” said Ursula Nelson, PDEQ Director. “If the Pima County region violates this standard in the future, both businesses and residents will be negatively affected by not only the health impacts of breathing unhealthy air, but also shouldering the costs of actions that will need to be taken to reduce the emissions that contribute to ozone formation,” said Nelson. According to EPA, required actions for a community to take to return to compliance if a violation of the ozone standard has occurred could include: more expensive reformulated gasoline; developing an emissions inventory; more businesses required to quantify and register emission levels with PDEQ; and a requirement called “offsets” where new or expanding businesses will need to find ways to reduce their emissions by ten percent. “By working together as a community, we hope to keep our air healthy and avoid violations in the future,” said Nelson.

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