Illinois Administrative Code
Title 35 - ENVIRONMENTAL PROTECTION
Part 204 - PREVENTION OF SIGNIFICANT DETERIORATION
Subpart D - INCREMENT
Section 204.900 - Ambient Air Increments
Current through Register Vol. 48, No. 38, September 20, 2024
a) In areas designated as Class I, II or III, increases in pollutant concentration over the baseline concentration shall be limited to the following:
|
Pollutant |
Maximum allowable increase (micrograms per cubic meter) |
|
Class I Area |
|
|
PM2.5: |
|
|
Annual arithmetic mean |
1 |
|
24-hr maximum |
2 |
|
PM10: |
|
|
Annual arithmetic mean |
4 |
|
24-hr maximum |
8 |
|
SO2: |
|
|
Annual arithmetic mean |
2 |
|
24-hr maximum |
5 |
|
3-hr maximum |
25 |
|
NO2: |
|
|
Annual arithmetic mean |
2.5 |
|
Class II Area |
|
|
PM2.5: |
|
|
Annual arithmetic mean |
4 |
|
24-hr maximum |
9 |
|
PM10: |
|
|
Annual arithmetic mean |
17 |
|
24-hr maximum |
30 |
|
SO2: |
|
|
Annual arithmetic mean |
20 |
|
24-hr maximum |
91 |
|
3-hr maximum |
512 |
|
NO2: |
|
|
Annual arithmetic mean |
25 |
|
Class III Area |
|
|
PM2.5: |
|
|
Annual arithmetic mean |
8 |
|
24-hr maximum |
18 |
|
PM10: |
|
|
Annual arithmetic mean |
34 |
|
24-hr maximum |
60 |
|
SO2: |
|
|
Annual arithmetic mean |
40 |
|
24-hr maximum |
182 |
|
3-hr maximum |
700 |
|
NO2: |
|
|
Annual arithmetic mean |
50 |
b) For any period other than an annual period, the applicable maximum allowable increase may be exceeded during one such period per year at any one location.
