1. (1) This rule defines significant deterioration. In areas designated as Class I, II or III, emissions from new or modified sources must be limited such that aggregate increases in regulated pollutant concentration over the baseline concentration, as defined in OAR 340-225-0020, are less than the following PSD increments or maximum allowable increases:

   1. (a) For Class I areas:

      1. (A) PM2.5:

         1. (i) Annual arithmetic mean = 1 microgram per cubic meter.
         2. (ii) 24-hour maximum = 2 micrograms per cubic meter.

      2. (B) PM10:

         1. (i) Annual arithmetic mean = 4 micrograms per cubic meter
         2. (ii) 24-hour maximum = 8 micrograms per cubic meter.

      3. (C) Sulfur dioxide:

         1. (i) Annual arithmetic mean = 2 micrograms per cubic meter.
         2. (ii) 24-hour maximum = 5 micrograms per cubic meter.
         3. (iii) 3-hour maximum = 25 micrograms per cubic meter.
      4. (D) Nitrogen dioxide: Annual arithmetic mean = 2.5 micrograms per cubic meter.

   2. (b) For Class II areas:

      1. (A) PM2.5:

         1. (i) Annual arithmetic mean = 4 micrograms per cubic meter.
         2. (ii) 24-hour maximum = 9 micrograms per cubic meter.

      2. (B) PM10:

         1. (i) Annual arithmetic mean = 17 micrograms per cubic meter.
         2. (ii) 24-hour maximum = 30 micrograms per cubic meter.

      3. (C) Sulfur dioxide:

         1. (i) Annual arithmetic mean = 20 micrograms per cubic meter.
         2. (ii) 24-hour maximum = 91 micrograms per cubic meter.
         3. (iii) 3-hour maximum = 512 micrograms per cubic meter.
      4. (D) Nitrogen dioxide: Annual arithmetic mean = 25 micrograms per cubic meter.

   3. (c) For Class III areas:

      1. (A) PM2.5:

         1. (i) Annual arithmetic mean = 8 micrograms per cubic meter.
         2. (ii) 24-hour maximum = 18 micrograms per cubic meter.

      2. (B) PM10:

         1. (i) Annual arithmetic mean = 34 micrograms per cubic meter.
         2. (ii) 24-hour maximum = 60 micrograms per cubic meter.

      3. (C) Sulfur dioxide:

         1. (i) Annual arithmetic mean = 40 micrograms per cubic meter.
         2. (ii) 24-hour maximum = 182 micrograms per cubic meter.
         3. (iii) 3-hour maximum= 700 micrograms per cubic meter.
      4. (D) Nitrogen dioxide: Annual arithmetic mean = 50 micrograms per cubic meter.

2. (2) For any period other than an annual period, the applicable maximum allowable increase or PSD increment may be exceeded during one such period per year at any one location.

   NOTE: This rule is included in the State of Oregon Clean Air Act Implementation Plan that EQC adopted under OAR 340-200-0040.

   [ED. NOTE: To view attachments referenced in rule text, click here for PDF copy.]

Statutory/Other Authority

ORS 468.020 & 468A

Statutes/Other Implemented

ORS 468A.025 & 468A.035

History

DEQ 13-2019, amend filed 05/16/2019, effective 05/16/2019
DEQ 54-2017, minor correction filed 12/19/2017, effective 12/19/2017
DEQ 7-2015, f. & cert. ef. 4-16-15
DEQ 5-2011, f. 4-29-11, cert. ef. 5-1-11
Reverted to DEQ 6-2001, f. 6-18-01, cert. ef. 7-1-01
DEQ 10-2010(Temp), f. 8-31-10, cert. ef. 9-1-10 thru 2-28-11
DEQ 6-2001, f. 6-18-01, cert. ef. 7-1-01
DEQ 14-1999, f. & cert. ef. 10-14-99, Renumbered from 340-031-0110
DEQ 17-1995, f. & cert. ef. 7-12-95
DEQ 7-1992, f. & cert. ef. 3-30-92
DEQ 8-1988, f. & cert. ef. 5-19-88 (corrected 9-30-88)
DEQ 18-1979, f. & ef. 6-22-79