(a) A person who
submits meteorological or ambient air monitoring data under AS 46.03, AS 46.14,
or this chapter shall obtain the data in accordance with
(1) the department's
Quality
Assurance Project Plan for the State of Alaska Air Monitoring & Quality
Assurance Program, adopted by reference in
18 AAC 50.030, for PM-2.5, PM-10,
total suspended particulates (TSP), lead, carbon monoxide, nitrogen dioxide,
sulfur dioxide, ozone, and ammonia;
(2) a reference method or an equivalent
method described in 40 C.F.R. Part
50, Appendices D and P, adopted by reference
in
18 AAC 50.035(b),
for ozone;
(3) EPA's
Meteorological Monitoring Guidance for Regulatory Modeling
Applications, adopted by reference in
18 AAC 50.035(a),
EPA 's
Quality Assurance Handbook for Air Pollutant Measurement
Systems; Volume IV; Meteorological Measurements Version 2.0, adopted
by reference in
18 AAC 50.035(a),
and the department's
Quality Assurance Project Plan for the State of
Alaska Air Monitoring & Quality Assurance Program, adopted by
reference in
18 AAC 50.030, for meteorological
data; or
(4) an alternative method
that is representative, accurate, verifiable, capable of replication, and
approved by the department.
(b) Except as provided in (c) of this
section, a person who submits an analysis performed to predict ambient air
quality conditions shall
(1) ensure that
estimates of ambient concentrations and impairment to visibility are based on
applicable air quality models, databases, and other requirements specified in
40 C.F.R. Part
51, Appendix W (Guideline on Air Quality Models), adopted by
reference in
18 AAC 50.040(f);
and
(2) for comparing predicted or
measured ambient concentrations of an air pollutant to a maximum allowable
increase established under
18 AAC 50.020, exclude
(A) concentrations attributable to a
temporary construction activity for a new or modified source; and
(B) the concentrations described under
40 C.F.R.
51.166(f), adopted by
reference in
18 AAC
50.040(h).
(c) A person may substitute or
modify a refined air quality model referenced in (b)(1) of this section only
after
(1) demonstrating, consistent with 40
C.F.R. Part
51, Appendix W (Guideline on Air Quality Models), Section 3.2
(Alternative Models), adopted by reference in
18 AAC 50.040(f),
that the alternative air quality model is more appropriate than a preferred air
quality model; and
(2) obtaining
approval from the regional administrator and the commissioner's
designee.
(d) A
stationary source or modification will be considered to cause or contribute to
a violation of an ambient air quality standard or maximum allowable increase
for a Class II area if the source or modification would, at a minimum, exceed a
significant impact level listed in Table 5 of this subsection at any locality
that does not or would not meet the applicable ambient air quality standard or
maximum allowable increase for a Class II area. A person shall conduct the
comparison of a modeled impact to the significant impact level as follows:
(1) for the PM-2.5 significant impact level,
the annual average PM-2.5 significant impact level, the one-hour nitrogen
dioxide significant impact level, or the one-hour sulfur dioxide significant
impact level, the person shall compare
(A)
the highest modeled concentration when using either one year of meteorological
data or screening meteorological data; or
(B) the highest multi-year average
concentration when using a multi-year meteorological data set;
(2) for all other pollutants and
averaging periods, the person shall use the highest modeled concentration.
Table 5
Significant Impact Levels (SILs)
Pollutant Significant impact level (micrograms per cubic
meter) Averaging period Annual 24 hours 8 hours 3 hours 1 hour Sulfur dioxide
1.05 N/A 258 PM-101.05 N/A N/A N/A PM-2.5.0 31.2 N/A N/A N/A Nitrogen dioxide
1.0 N/A N/A N/A 8 Carbon monoxide N/A N/A 500 N/A 2,000 Note to Table 5:
In this table, "N/A" means not applicable.
(e) repealed 9/15/2018.
Notes
18 AAC 50.215
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 4/1/2010, /Register 193; am 10/29/2010, Register
196; am 9/17/2011, Register 199; am 9/14/2012, Register 203; am 1/4/2013,
Register 205; am 4/17/2015,
Register
214, July 2015; am 8/20/2016,
Register
219, October 2016; am 9/15/2018,Register
227, October 2018
Authority:AS
46.03.020
AS
46.14.030
AS
46.14.140
AS
46.14.180
Sec. 30, ch. 74, SLA
1993