Chapter 2 PM 2.5 Air Quality Data Table 2-16
Air Basin* Year Maximum 24-Hour Concentration (µg/m3) 98th Percentile 24-Hour Concentration (µg/m3)** 98th Percentile Concentration Valid?** Average of Quarters (µg/m3)** Average of Quarters Valid?**
Great Basin Valleys 1999 40.7 30.9 N 7.2 N
2000 68.0 67.0 Y 18.0 N
2001 76.0 41.0 N 10.3 N
Lake County 1999 14.5 14.5 N 4.3 N
2000 9.4 9.4 N 4.0 N
2001 15.1 11.3 Y 4.2 Y
Lake Tahoe 1999 21.0 21.0 Y 8.3 Y
2000 23.0 21.0 Y 7.8 Y
2001 31.0 26.0 Y 8.2 Y
Mojave Desert 1999 47.6 23.5 Y 11.9 Y
2000 38.6 26.4 N 11.9 Y
2001 35.0 29.0 N 11.5 Y
Mountain Counties 1999 92.0 84.0 Y 13.3 N
2000 48.0 44.0 N 10.6 N
2001 120.0 43.0 Y 15.6 Y
North Central Coast 1999 31.4 23.6 N 9.8 N
2000 26.4 21.5 N 7.9 N
2001 25.6 23.1 N 9.1 N
North Coast 1999 36.9 27.7 Y 9.1 Y
2000 24.0 21.5 Y 9.1 Y
2001 38.3 29.0 Y 9.4 Y
Northeast Plateau 1999 40.0 27.0 Y 7.9 Y
2000 38.0 37.0 Y 8.5 Y
2001 35.0 35.0 N 7.6 N
Sacramento Valley 1999 108.0 71.0 Y 23.7 N
2000 98.0 70.0 Y 15.8 Y
2001 72.0 56.0 Y 13.0 Y
Salton Sea 1999 52.5 43.2 N 15.2 Y
2000 84.2 56.0 Y 16.9 Y
2001 60.2 50.4 N 14.9 N
San Diego 1999 64.3 45.1 N 18.0 Y
2000 66.3 48.7 N 15.8 Y
2001 60.0 40.8 Y 17.7 Y
San Francisco Bay Area 1999 90.5 53.8 N 28.1 N
2000 67.2 55.3 Y 13.6 Y
2001 107.5 56.0 Y 12.5 Y
San Joaquin Valley 1999 136.0 120.0 Y 27.7 Y
2000 160.0 108.0 Y 25.5 N
2001 154.7 120.6 Y 22.5 Y
South Central Coast 1999 64.6 35.4 Y 13.8 Y
2000 55.3 42.4 N 14.8 N
2001 57.6 50.7 Y 14.9 Y
South Coast 1999 121.4 85.6 Y 31.0 Y
2000 119.6 83.0 Y 28.3 Y
2001 98.0 74.3 Y 31.0 Y
"* The table lists the highest value for each statistic. Within an air basin, the highest value for each statistic may reflect a different site."
"** These statistics and determination of their validity are calculated according to the methods specified in 40 CFR Part 50, Appendix N. Validity is based on the number of measurements"
"available per quarter and therefore, depends on completeness. Both the 98th percentile concentration and the average of quarters concentration relate to the national PM2.5 standards,"
while only the average of quarters concentration relates to the State PM2.5 standard.