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Current as of January 02, 2025 | Updated by Findlaw Staff
(a) In accordance with section 181(a)(1) of the CAA, each area subject to § 51.902(a) shall be classified by operation of law at the time of designation. However, the classification shall be based on the 8–hour design value for the area, in accordance with Table 1 below, or such higher or lower classification as the State may request as provided in paragraphs (b) and (c) of this section. The 8–hour design value for the area shall be calculated using the three most recent years of air quality data. For each area classified under this section, the primary NAAQS attainment date for the 8–hour NAAQS shall be as expeditious as practicable but not later than the date provided in the following Table 1.
|
Table 1—Classification for 8-Hour Ozone NAAQS for Areas Subject to § 51.902(a) |
||||
|---|---|---|---|---|
|
Area class |
8-hour design value (ppm ozone) |
Maximum period for attainment dates in state plans (years after effective date of nonattainment designation for 8-hour NAAQS) |
||
|
Marginal |
from |
0.085 |
3 |
|
|
up to 1 |
0.092 |
|||
|
Moderate |
from |
0.092 |
6 |
|
|
up to 1 |
0.107 |
|||
|
Serious |
from |
0.107 |
9 |
|
|
up to 1 |
0.120 |
|||
|
Severe-15 |
from |
0.120 |
15 |
|
|
up to 1 |
0.127 |
|||
|
Severe-17 |
from |
0.127 |
17 |
|
|
up to 1 |
0.187 |
|||
|
Extreme |
equal to |
0.187 |
20 |
|
|
or above |
1 but not including.
(b) A State may request a higher classification for any reason in accordance with section 181(b)(3) of the CAA.
(c) A State may request a lower classification in accordance with section 181(a)(4) of the CAA.
Cite this article: FindLaw.com - Code of Federal Regulations Title 40. Protection of Environment § 40.51.903 How do the classification and attainment date provisions in section 181 of subpart 2 of the CAA apply to areas subject to § 51.902(a)? - last updated January 02, 2025 | https://codes.findlaw.com/cfr/title-40-protection-of-environment/cfr-sect-40-51-903/
FindLaw Codes may not reflect the most recent version of the law in your jurisdiction. Please verify the status of the code you are researching with the state legislature before relying on it for your legal needs.
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