Ambient air increments and ceilings

(a) Ambient air increments. Increases in pollutant concentration over the baseline concentration in Class I, II, or III areas shall be limited to those listed in OAC 252:100-3-4 regarding significant deterioration increments. (b) Ambient air ceilings. DEQ shall confirm that either (1) or (2) below has been addressed by the applicant for each pollutant determined to be significant for the PSD permit in question. (1) By modeling or monitoring, the applicant has demonstrated that noNo concentration of athe pollutant shall exceedexceeds whichever of the following concentrations, in subparagraph (A) or (B) below, is lowest for the pollutant for a period of exposure:. (A) the concentration allowed under the secondary NAAQS, or AQAC_2026_JUL_SC_7_8_10_RUL 12 June 15, 2026 (2)(B) the concentration permitted under the primary NAAQS. (2) That all project emission increases determined to be significant for the pollutant in question have been offset by the extinguishment of a sufficient number of ERCs in accordance with OAC 252:100-10-3, 10-4(b), 10-4(c), and 10-7.