Nonattainment areas that failed to meet the 1-hour ozone standard in 1999-2001

Areas designated nonattainment in 1991(1) that failed
to meet the 1-hr ozone NAAQS in 2000-2002

State

Designated Area

Ozone Design
Value(2) (ppm)

AL	Birmingham	0.127
CA	Los Angeles South Coast Air Basin	0.169
CA	Sacramento Metro	0.148
CA	San Francisco Bay Area	0.126
CA	San Joaquin Valley	0.151
CA	Southeast Desert Modified AQMA	0.146
CA	Imperial Co.	0.147
CT	Greater Connecticut	0.146
CT	New York-N. New Jersey-Long Island, NY-NJ-CT	0.149
GA	Athens (4)	0.110
GA	Atlanta	0.144
GA	Macon	0.125
LA	Baton Rouge	0.135
ME	Portland	0.126
MD	Baltimore	0.143
MD	Kent and Queen Anne's Counties	0.128
MA	Boston-Lawrence-Worchester (E. MA), MA-NH	0.130
MA	Springfield (Western MA)	0.132
NH	Manchester	0.123
NH	Portmouth-Dover-Rochester (4)	0.111
NY	Poughkeepsie	0.126
NC	Charlotte-Gastonia	0.130
OH	Cleveland-Akron-Lorain	0.128
PA	Philadelphia-Wilmington-Trenton, PA-NJ-DE-MD	0.135
RI	Providence (All RI)	0.130
TN	Knoxville (4)	0.116
TX	Dallas-Fort Worth	0.135
TX	Houston-Galveston-Brazoria	0.175
VA	Richmond-Petersburg	0.124
VA	Washington DC-MD-VA	0.131
WI	Chicago-Gary-Lake County	0.134
WI	Milwaukee-Racine	0.125

Notes:

1. Designations and classifications for ozone nonattainment areas as published in the Federal Register, 40 CFR Part 81. Unclassified and transitional nonattainment areas are not included in Table in this table.

2. The updated air quality design value is estimated for the 2000-2002 period using all air quality data reported to EPA's Air Quality System (AQS). The computation procedures follow EPA guidance for calculating design values (Laxton Memorandum, June 18, 1990). For sites with three complete years of monitoring data, the air quality design value is the fourth highest daily maximum 1-hour ozone concentration, because the standard allows one exceedance per year on average. It is important to note that the 1990 Clean Air Act Amendments required that nonattainment areas be classified on the basis of the design value at the time the Amendments were passed, generally the 1987-89 period was used.

3. The level of the 1-hour ozone Ambient Air Quality standard is 0.12 parts per million (ppm) daily maximum 1-hour average concentration not to be exceeded more than once per year on average. The average estimated number of exceedances column shows the number of days the 0.12 ppm 1-hour ozone standard was exceeded on average at the site recording the highest updated air quality value. This computation is performed after adjustment for any missing sampling days during the 3-year period, 2000-2002. The values in parentheses are associated with the monitor with highest average estimated number of exceedances within the designated area; sometimes this statistic is associated with a different site than the site recording the highest updated air quality value.

4. These areas have an average expected exceedances for 2000-2002 greater than 1 but a design value that is less than 0.125 ppm. Further review will be required before determining the applicability of the estimated design value due to less than 3 valid years of data.

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