Ozone Monitoring Network

Oregon 1-hour Avg. Ozone Exceedances Oregon violated the 1-hour standard in 1998. However, because some of the emission reduction strategies were not fully implemented in 1998, EPA did not require new contingency measures to be implemented. Fortunately, Oregon has not violated the standard since 1998.

Oregon 8-hour Avg. Ozone Exceedances 2002 exceedance occurred on 7/10/02 (0.085 ppm 8-hour average). Highest value in 2003 was on 6/7/03 (Saturday, CAAD, Rose Parade). One-hour peak was .09 at 5:00 pm and highest 8-hour running average was .07 ppm. 8-hour ozone values prior to 1997 were re-calculated using existing data and are presented here for trend purposes and NOT for determining attainment. Oregon exceeded the 8-hour ozone standard on July 21, 2002 at the “Carus” site southeast of Portland. However, because the three-year average of the 4th highest value is still below 0.085, we did not violate the standard.

Oregon 8-hour Avg. Ozone Compliance Rolling 3-yr avg. of 4th highest daily O3 level Oregon has seven monitoring sites for ozone: 2 in Portland 1 in Salem 2 in Eugene 1 in Medford This graph plots the running 3-year average of the 4th highest 8-hour ozone value at each monitoring site in Oregon. In other words, the 2002 values represent the average of the 4th highest 8-hour ozone value during 2000, 2001 and 2002.

Oregon 2003 Ozone Data raw data from DAS system Sauvie Island Carus Turner Talent 1-hour 8-hour 6/5 .087 .07 .079 6/6 .069 .068 .090 .095 6/7 .052 .09 6/28 .071 .06 .076 .066 .083 .075 .089 7/18 .062 .055 .082 .074 7/21 .065 .072 .078 .060 .08 .063