Green Book

You are here: EPA Home > Green Book > 1-Hour Ozone (1979) Section 185A Nonattainment Areas - NAAQS Revoked

1-Hour Ozone (1979) Section 185A Nonattainment Areas - NAAQS Revoked

Data is current as of June 15, 2005

Areas Listed Alphabetically Design
Values
(ppm)
Avg
Expected
Exceedences
No.
NAA
Counties
2000
Pop.
(1000's)
EPA
Region
State Located
in
MSA/
CMSA
Chico, CA 0.100 0.0 1 203 9 CA msa
Imperial Co, CA 0.110 0.0 1 142 9 CA no
Yuba City, CA 0.120 1.0 2 114 9 CA msa
 
3 Total Areas 4 459  
 
"Section 185A" was previously called "Transitional". Prior designation retained by operation of law in 1991 but without measured violation based on 1987-89 data. Totals were adjusted to account for multiple areas in a single county. The former 1-Hour Ozone designations and classifications as of June 15, 2004, are being retained in subpart C of Part 81 for purposes of the anti backsliding provisions of 40 CFR 51.905. 40 CFR 51.905(c) references subpart C of part 81 for the areas affected by the anti-backsliding regulation.