1. (a) In an area designated nonattainment in 18 AAC 50.015(b), the provisions of this section do not apply to the nonattainment air pollutant. However, this section does apply to all other air pollutants listed in Table 2 in this subsection. Table 2 Baseline Areas and Dates Baseline AreaAir PollutantMinor Source Baseline DateCook Inlet Intrastate Air Quality Control RegionNitrogen dioxideFebruary 8, 1988Sulfur dioxideOctober 12, 1979PM-10March 20, 1982PM-2.5September 14, 2012Northern Alaska Intrastate Air Quality Control RegionNitrogen dioxideFebruary 8, 1988Sulfur dioxideJune 1, 1979PM-10November 13, 1978PM-2.5November 2, 2012South Central Alaska Intrastate Air Quality Control RegionNitrogen dioxideFebruary 8, 1988Sulfur dioxideOctober 26, 1979PM-10October 26, 1979PM-2.5October 15, 2015Southeast Alaska Intrastate Air Quality Control RegionNitrogen dioxideFebruary 8, 1988Sulfur dioxideNovember 10, 1986PM-10To be established under 40 C.F.R. 52.21(b)(14)(ii), adopted by reference in 18 AAC 50.040(h)PM-2.5To be established under 40 C.F.R. 52.21(b)(14)(ii), adopted by reference in 18 AAC 50.040(h)

2. (b) To establish standards for the prevention of significant deterioration of air quality,

   1. (1) minor source baseline dates for determining the ambient concentration of certain air pollutants are established for each baseline area listed in Table 2 in (a) of this section;
   2. (2) in areas designated as Class I, II, or III, increases in air pollutant concentration over the baseline concentration shall be limited to the concentrations in Table 3 in this subsection;
   3. (3) 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;
   4. (4) the baseline concentrations and maximum allowable increases shall be measured or predicted by a method described in 18 AAC 50.215; and
   5. (5) a concentration may not exceed the ambient air quality standard described in 18 AAC 50.010 for that pollutant.

   Table 3

   Maximum Allowable Increases

   Classification of area

   in 18 AAC 50.015(c)

   Table 1Air PollutantMaximum allowable

   increase (micrograms

   per cubic meter)CLASS 1PM-10:Annual arithmetic mean . . . . . . . . . . . . . . . . . . . . . . . . 424-hour maximum . . . . . . . . . . . . . . . . . . . . . . . . 8Sulfur dioxide:Annual arithmetic mean . . . . . . . . . . . . . . . . . . . . . . . . 224-hour maximum . . . . . . . . . . . . . . . . . . . . . . . . 53-hour maximum . . . . . . . . . . . . . . . . . . . . . . . . 25Nitrogen dioxide:Annual arithmetic mean . . . . . . . . . . . . . . . . . . . . . . . . 2.5PM-2.5:Annual arithmetic mean . . . . . . . . . . . . . . . . . . . . . . . . 124-hour maximum . . . . . . . . . . . . . . . . . . . . . . . . 2CLASS IIPM-10:Annual arithmetic mean . . . . . . . . . . . . . . . . . . . . . . . . 1724-hour maximum . . . . . . . . . . . . . . . . . . . . . . . . 30Sulfur dioxide:Annual arithmetic mean . . . . . . . . . . . . . . . . . . . . . . . . 2024-hour maximum . . . . . . . . . . . . . . . . . . . . . . . . 913-hour maximum . . . . . . . . . . . . . . . . . . . . . . . . 512Nitrogen dioxide:Annual arithmetic mean . . . . . . . . . . . . . . . . . . . . . . . . 25PM-2.5:Annual arithmetic mean . . . . . . . . . . . . . . . . . . . . . . . . 424-hour maximum . . . . . . . . . . . . . . . . . . . . . . . . 9CLASS IIIPM-10:Annual arithmetic mean . . . . . . . . . . . . . . . . . . . . . . . . 3424-hour maximum . . . . . . . . . . . . . . . . . . . . . . . . 60Sulfur dioxide:Annual arithmetic mean . . . . . . . . . . . . . . . . . . . . . . . . 4024-hour maximum . . . . . . . . . . . . . . . . . . . . . . . . 1823-hour maximum . . . . . . . . . . . . . . . . . . . . . . . . 700Nitrogen dioxide:Annual arithmetic mean . . . . . . . . . . . . . . . . . . . . . . . . 50PM-2.5:Annual arithmetic mean . . . . . . . . . . . . . . . . . . . . . . . . 824-hour maximum . . . . . . . . . . . . . . . . . . . . . . . . 18

3. (c) Repealed 10/1/2004.
4. (d) Repealed 10/1/2004.
5. (e) For purposes of this section, the baseline concentrations within a baseline area are determined in accordance with 40 C.F.R. 52.21(b)(13), adopted by reference in 18 AAC 50.040(h).
6. (f) In this section "commence" has the meaning given in 40 C.F.R. 52.21(b), adopted by reference in 18 AAC 50.040.

7. (g) For purposes of this section, the baseline area is every part of an air quality control region described in 18 AAC 50.015 that is designated as attainment or unclassifiable, and in which the major source or major modification establishing the minor source baseline date would construct or would have an air quality impact for the pollutant for which the baseline date is established, as follows:

   1. (1) equal to or greater than one microgram per cubic meter on an annual average basis for sulfur dioxide, nitrogen dioxide, or PM-10;
   2. (2) equal to or greater than 0.3 micrograms per cubic meter on an annual average basis for PM-2.5.

(Eff. 1/18/97, Register 141; am 6/21/98, Register 146; am 10/1/2004, Register 171; am 7/25/2008, Register 187; am 1/4/2013, Register 205; am 4/17/2015, Register 214; am 8/20/2016, Register 219)

Authority: AS 46.03.020, AS 46.14.010, AS 46.14.030