The New Ozone and PM Standards: Will we breathe more easily?

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Hotline, Summer 1997

As the next article, a presentation by President Kocoshis, demonstrates, there was great input sought in creating the final recommendation of the new ozone and 2.5 particulate standards. In fact, the Clean Air Scientific Advisory Council held 125 public discussions and based upon 250 of the most relevant scientific studies concluded that EPAs current standards be strengthened. EPA then proposed updated standards and conducted an extensive comment process, receiving approximately 57,000 comments at public hearings and through written comment. The standards were also subjected to an interagency review process. The final recommended standards which were less stringent than EPA originally proposed were supported by President Clinton on June 25, 1997. The EPA updated standards also carry an implementation package. So what are they?

The new standard for ozone will move from a one hour average of 120 parts per billion (ppb) not to be exceeded more than three times over a three year period at the same monitor, to an eight hour average of 80 ppb (using the fourth highest eight hour average reading) each year. The three annual readings then to be averaged and not to exceed 80 ppb. So far this summer, Pittsburgh has had three exceedances of the one hour standard at the Harrison monitor which means we are not eligible for another years extension to achieve attainment and therefore may be bumped up from moderate non-attainment to a serious non-attainment category (using the one hour standard). The EPA reevaluates the Pittsburgh attainment status at the end of the ozone season. However, many of the ozone reduction strategies developed in the Ozone Stakeholders Working Group, such as the Inspection and Maintenance program for auto emissions has not yet been put into effect but will be implemented soon, in this case in October of 1997.

The new standard for fine particles of 2.5 microns in diameter calls for daily average standard not to exceed 65 micrograms per cubic meter of air and a yearly average of 15 micrometers per cubic meter of air. The annual 2.5 standard will use an annual mean in a three year average. This does not affect the regulations for PM 10 which is the larger sized particle upon which small particulate regulations are now set. Those standards are no more than three violations of over 150 micrograms per cubic meter of air at the same monitor averaged over a three year period, as well as a 50 micrograms average per cubic meter of air annual standard .

Since the PM 2.5 standard is the first standard for this pollutant, the EPA will allow five years to set up a new monitoring network as well as another review of particulate matter science during that time. The 2.5 standard to be reevaluated again in five years when data has been collected and the review completed. While new standards will hopefully provide better air quality, the phrase the devil is in the details, is not inappropriate.

For PM 2.5, there will be spatial averaging of the monitors. This could mean if one monitor is high within a spatial region, another could be added getting lower readings thus providing a lower average reading that would form the basis for measurement. Nevertheless, people in the vicinity of the high monitor would still be exposed to unhealthy levels of PM 2.5. The guidance for allowable spatial regions and monitor sights is under development. At this time, it appears any additional monitors in a spatial area will have to have readings within a close percentage of the hot spot monitor-percentage and be affected by the same sources. The spatial averaging will affect the annual standard only.

There is also a new category of PM 2.5 monitor called a community monitor meaning it should be in a populated vicinity and not monitor primarily for industry emissions such as those occurring at the hill across from the Clairton Coke Plant. (This was the specific example used by an EPA spokesperson). For the industry monitor, only the daily standard will be counted. The annual standard will not apply.

The PM 2.5 twenty-four hour standard will also take only those readings falling at the 98th percentile of monitored days per year excusing the top two percent of monitored data or the top approximately 7 daily readings per year, if monitoring occurred every day of the year. The annual 98th percentile reading to be averaged over three years.

When will the new standards actually cause reduced pollution? Local controls for the eight hour ozone standard will not be required until 2003, and 2005 for particulate matter ; with no compliance determinations until 2007 and 2008 respectively and with possible extensions.

The EPA will work with the Ozone Transport Assessment Group (OTAG) and their data to ask for State Implementation Plans from states that are causing significant upwind pollution to help reduce the interstate pollution. Those areas such as Pittsburgh that have not attained the one hour ozone standard can be eligible for a transitional classification process if we meet the one hour standard by the year 2000 and submit a SIP for the 8-hour standard prior to the designation and classification process in 2000, and comply with EPAs regional transport rule as applicable.

EPA states that the new standards will prevent 15,000 premature deaths, 350,000 cases of aggravated asthma and 1 million cases of significantly decreased lung function achieved in a flexible and cost effective manner. The standards, as you have observed from the above, do not simply lower pollutant standards . There is a different, complex methodology involved and a very long time for implementation. Hopefully, this new approach is actually able to achieve decreased levels of ozone and PM 2.5. The EPA and President Clinton are to be congratulated for taking a stand for cleaner air against strong opposition. GASP hopes that the changes put into the original EPA proposal are not so weakening that the whole complex effort eventually arrives at the same or little improved air quality place. This much effort and debate should have real results in human and environmental health.

By Sue Seppi, GASP Vice President