Document ID: EPA-R10-OAR-2018-0823-0001
Agency: epa
Document Type: Proposed Rule
Title: Air Quality State Implementation Plans; Approvals and Promulgations: Alaska; Interstate Transport Requirements for the 2015 Ozone Standard
Posted Date: 2019-06-05T04:00Z

[Federal Register Volume 84, Number 108 (Wednesday, June 5, 2019)]
[Proposed Rules]
[Pages 26041-26047]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2019-11764]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R10-OAR-2018-0823, FRL-9994-48-Region 10]

Air Plan Approval; AK: Interstate Transport Requirements for the 
2015 Ozone Standard

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: The Clean Air Act requires each State Implementation Plan 
(SIP) to contain adequate provisions prohibiting emissions that will 
have certain adverse air quality effects in other states. On October 
25, 2018, the State of Alaska made a submission to the Environmental 
Protection Agency (EPA) to address these requirements for the 2015 
ozone National Ambient Air Quality Standards (NAAQS). The EPA is 
proposing to approve the Alaska SIP as meeting the requirement that 
each SIP contain adequate provisions to prohibit emissions that will 
significantly contribute to nonattainment or interfere with maintenance 
of the 2015 ozone NAAQS in any other state.

DATES: Comments must be received on or before July 5, 2019.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-R10-
OAR-2018-0823, at https://www.regulations.gov. Follow the online 
instructions for submitting comments. Once submitted, comments cannot 
be edited or removed from Regulations.gov. The EPA may publish any 
comment received to its public docket. Do not electronically submit any 
information you consider to be Confidential Business Information (CBI) 
or other information the disclosure of which is restricted by statute. 
Multimedia submissions (audio, video, etc.) must be accompanied by a 
written comment. The written comment is considered the official comment 
and should include discussion of all points you wish to make. The EPA 
will generally not consider comments or comment contents located 
outside of the primary submission (i.e. on the web, cloud, or other 
file sharing system). For additional submission methods, the full EPA 
public comment policy, information about CBI or multimedia submissions, 
and general guidance on making effective comments, please visit https://www.epa.gov/dockets/commenting-epa-dockets.

FOR FURTHER INFORMATION CONTACT: Kristin Hall, EPA Region 10, Air and

[[Page 26042]]

Radiation Division, 1200 Sixth Avenue, Seattle, WA 98101, at (206) 553-
6357 or hall.kristin@epa.gov.

SUPPLEMENTARY INFORMATION: Throughout this document wherever ``we,'' 
``us,'' or ``our'' is used, it means the EPA.

Table of Contents

I. Background
II. State Submission
III. EPA Evaluation
IV. Proposed Action
V. Statutory and Executive Order Reviews

I. Background

    On October 1, 2015, the EPA promulgated a revision to the ozone 
NAAQS (2015 ozone NAAQS), lowering the level of both the primary and 
secondary standards to 0.070 parts per million (ppm).\1\ Section 
110(a)(1) of the Clean Air Act (CAA) requires states to submit, within 
three years after promulgation of a new or revised standard, SIPs 
meeting the applicable requirements of section 110(a)(2).\2\ One of 
these applicable requirements is found in section 110(a)(2)(D)(i), 
otherwise known as the good neighbor provision, which generally 
requires SIPs to contain adequate provisions to prohibit in-state 
emissions activities from having certain adverse air quality effects on 
other states due to interstate transport of pollution. There are four 
so-called ``prongs'' within CAA section 110(a)(2)(D)(i): Section 
110(a)(2)(D)(i)(I) contains prongs 1 and 2, while section 
110(a)(2)(D)(i)(II) includes prongs 3 and 4. This action addresses the 
first two prongs under section 110(a)(2)(D)(i)(I). Under prongs 1 and 2 
of the good neighbor provision, a SIP for a new or revised NAAQS must 
contain adequate provisions prohibiting any source or other type of 
emissions activity within the state from emitting air pollutants in 
amounts that will significantly contribute to nonattainment of the 
NAAQS in another state (prong 1) or that will interfere with 
maintenance of the NAAQS in another state (prong 2). Under section 
110(a)(2)(D)(i)(I) of the CAA, the EPA and states must give independent 
significance to prong 1 and prong 2 when evaluating downwind air 
quality problems.\3\
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    \1\ See National Ambient Air Quality Standards for Ozone, Final 
Rule, 80 FR 65292 (October 26, 2015). Although the level of the 
standard is specified in the units of ppm, ozone concentrations are 
also described in parts per billion (ppb). For example, 0.070 ppm is 
equivalent to 70 ppb.
    \2\ SIP revisions that are intended to meet the applicable 
requirements of section 110(a)(1) and (2) of the CAA are often 
referred to as infrastructure SIPs and the applicable elements under 
110(a)(2) are referred to as infrastructure requirements.
    \3\ See North Carolina v. EPA, 531 F.3d 896, 909-911 (2008).
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Regional Regulatory Actions

    The EPA has addressed the interstate transport requirements of CAA 
section 110(a)(2)(D)(i)(I) prongs 1 and 2 with respect to prior ozone 
NAAQS in several regional regulatory actions, including the Cross-State 
Air Pollution Rule (CSAPR), which addressed interstate transport for 
purposes of the 1997 ozone NAAQS (as well as the 1997 and 2006 fine 
particulate matter standards) and the Cross-State Air Pollution Rule 
Update, which addressed interstate transport for purposes of the 2008 
ozone NAAQS (CSAPR Update).\4\ CSAPR and the CSAPR Update did not 
address interstate transport for the 2015 ozone NAAQS and also made no 
specific findings with respect to Alaska. Alaska is not part of the 
contiguous United States and is not fully contained within the 12 
kilometer (km) eastern modeling domain established to inform CSAPR and 
the CSAPR Update. The 12 km eastern modeling domain identified the 
Western United States (the West) as the 11 western contiguous states of 
Arizona, California, Colorado, Idaho, Montana, Nevada, New Mexico, 
Oregon, Utah, Washington, and Wyoming. The Eastern United States (the 
East) was identified as the 37 states east of the 11 western states.
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    \4\ See 76 FR 48208 (August 8, 2011) (i.e., CSAPR) and 81 FR 
74504 (October 26, 2016) (i.e., CSAPR Update).
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Four-Step Framework

    The EPA, working in partnership with states to develop and 
implement CSAPR, the CSAPR Update, and previous regional rulemakings 
pursuant to the good neighbor provision,\5\ developed the following 
four-step framework to address the requirements of the good neighbor 
provision for the ozone NAAQS: \6\ (1) Identify downwind air quality 
problems; (2) identify upwind states that impact those downwind air 
quality problems sufficiently such that they are considered ``linked'' 
and therefore warrant further review and analysis; (3) identify the 
emissions reductions necessary (if any), considering cost and air 
quality factors, to prevent linked upwind states identified in step 2 
from contributing significantly to nonattainment or interfering with 
maintenance of the NAAQS at the locations of the downwind air quality 
problems; and (4) adopt permanent and enforceable measures needed to 
achieve those emissions reductions.
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    \5\ Other regional rulemakings addressing ozone transport 
include the NOX SIP Call, 63 FR 57356 (October 27, 1998), 
and the Clean Air Interstate Rule (CAIR), 70 FR 25162 (May 12, 
2005).
    \6\ The four-step framework has also been used to address 
requirements of the good neighbor provision for some previous 
particulate matter and ozone NAAQS, including in the western United 
States. See, e.g., 83 FR 30380 (June 28, 2018) and 83 FR 5375, 5376-
77 (February 7, 2018).
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Data To Assist States

    To assist states, the EPA released several documents containing 
information relevant to evaluating interstate transport with respect to 
the 2015 ozone NAAQS, and we describe those documents in the following 
sections. However, none of these documents consider ozone precursor 
emissions to or from Alaska, and none project design values at 
monitoring sites located in Alaska, nor apportion specific downwind 
impacts to Alaska. Nonetheless, we have included all background 
information to provide a complete accounting of the EPA's data 
releases.

2017 Data Release and Memorandum

    On January 6, 2017, the EPA published a notice of data availability 
(NODA) for preliminary interstate ozone transport modeling with 
projected ozone design values for 2023, on which we requested 
comment.\7\ The year 2023 was used as the analytic year for this 
preliminary modeling because that year aligns with the expected 
attainment year for ozone nonattainment areas classified as 
Moderate.\8\ On October 27, 2017, we released a memorandum (2017 
memorandum) containing updated modeling data for 2023, which 
incorporated changes made in response to comments on the NODA.\9\ 
Although the 2017 memorandum also released data for a 2023 modeling 
year, we specifically stated that the modeling may be useful for states 
developing SIPs to address remaining good neighbor obligations for the 
2008 ozone NAAQS but did not address the 2015 ozone NAAQS.
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    \7\ See Notice of Availability of the Environmental Protection 
Agency's Preliminary Interstate Ozone Transport Modeling Data for 
the 2015 Ozone National Ambient Air Quality Standard (NAAQS), 82 FR 
1733 (January 6, 2017).
    \8\ 82 FR 1735 (January 6, 2017).
    \9\ See Information on the Interstate Transport State 
Implementation Plan Submissions for the 2008 Ozone National Ambient 
Air Quality Standards under Clean Air Act Section 
110(a)(2)(D)(i)(I), October 27, 2017, available in the docket for 
this action or at https://www.epa.gov/interstate-air-pollution-transport/interstate-air-pollution-transport-memos-and-notices.
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2018 Data Release and Memoranda

    On March 27, 2018, we issued a memorandum (March 2018

[[Page 26043]]

memorandum) indicating the same 2023 modeling data released in the 2017 
memorandum would also be useful for evaluating potential downwind air 
quality problems with respect to the 2015 ozone NAAQS (step 1 of the 
four-step framework). The March 2018 memorandum included newly 
available contribution modeling results to assist states in evaluating 
their impact on potential downwind air quality problems (step 2 of the 
four-step framework) as part of efforts to develop good neighbor SIPs 
for the 2015 ozone NAAQS.\10\ The EPA subsequently issued two more 
memoranda in August and October of 2018, providing guidance to states 
developing good neighbor SIPs for the 2015 ozone NAAQS concerning, 
respectively, potential contribution thresholds that may be appropriate 
to apply in step 2 and considerations for identifying downwind areas 
that may have problems maintaining the standard (under prong 2 of the 
good neighbor provision) at step 1 of the four-step framework.\11\
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    \10\ See Information on the Interstate Transport State 
Implementation Plan Submissions for the 2015 Ozone National Ambient 
Air Quality Standards under Clean Air Act Section 
110(a)(2)(D)(i)(I), March 27, 2018, available in the docket for this 
action and at https://www.epa.gov/interstate-air-pollution-transport/interstate-air-pollution-transport-memos-and-notices.
    \11\ See Analysis of Contribution Thresholds for Use in Clean 
Air Act Section 110(a)(2)(D)(i)(I) Interstate Transport State 
Implementation Plan Submissions for the 2015 Ozone National Ambient 
Air Quality Standards, August 31, 2018) (``August 2018 
memorandum''), and Considerations for Identifying Maintenance 
Receptors for Use in Clean Air Act Section 110(a)(2)(D)(i)(I) 
Interstate Transport State Implementation Plan Submissions for the 
2015 Ozone National Ambient Air Quality Standards, October 19, 2018, 
available in the docket for this action and at https://www.epa.gov/airmarkets/memo-and-supplemental-information-regarding-interstate-transport-sips-2015-ozone-naaqs.
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March 2018 Memorandum

    The March 2018 memorandum describes the process and results of the 
updated photochemical and source-apportionment modeling used to project 
ambient ozone concentrations for the year 2023 and the state-by-state 
impacts on those concentrations. The March 2018 memorandum also 
explains that the selection of the 2023 analytic year aligns with the 
2015 ozone NAAQS attainment year for Moderate nonattainment areas. As 
described in more detail in the 2017 and March 2018 memoranda, the EPA 
used the Comprehensive Air Quality Model with Extensions (CAMx version 
6.40) to model average and maximum design values in 2023 to identify 
potential nonattainment and maintenance receptors (i.e., monitoring 
sites that are projected to have problems attaining or maintaining the 
2015 ozone NAAQS). The March 2018 memorandum presents design values 
calculated in two ways. First, the EPA followed its past approach \12\ 
of using model predictions from the 3 x 3 array of grid cells 
surrounding the location of all monitoring sites (referred to as the 
``3 x 3'' approach). Second, the EPA followed a modified approach for 
coastal monitoring sites in which ``overwater'' modeling data were not 
included in the calculation of future year design values (referred to 
as the ``no water'' approach).
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    \12\ See March 2018 memorandum, p. 4.
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    For purposes of identifying potential nonattainment and maintenance 
receptors in 2023, the EPA applied the same approach used in the CSAPR 
Update, wherein the EPA considered a combination of monitoring data and 
modeling projections to identify monitoring sites that are projected to 
have problems attaining or maintaining the NAAQS. Specifically, the EPA 
identified nonattainment receptors as those monitoring sites with 
current measured values \13\ exceeding the NAAQS that also have 
projected (i.e., in 2023) average design values exceeding the NAAQS. 
The EPA identified maintenance receptors as those monitoring sites with 
maximum design values exceeding the NAAQS. This included sites with 
current measured values below the NAAQS with projected average and 
maximum design values exceeding the NAAQS, and monitoring sites with 
projected average design values below the NAAQS but with projected 
maximum design values exceeding the NAAQS. The EPA included the design 
values and monitoring data for all monitoring sites projected to be 
potential nonattainment or maintenance receptors based on the updated 
2023 modeling in attachment B to the March 2018 memorandum.
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    \13\ The EPA used 2016 ozone design values, based on 2014 
through 2016 measured data, which were the most current data at the 
time of the analysis. See attachment B of the March 2018 memorandum, 
p. B-1.
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    After identifying potential downwind nonattainment and maintenance 
receptors, the EPA next performed state-level ozone source-
apportionment modeling for the 48 contiguous United States and the 
District of Columbia to estimate the expected impact from each state to 
each nonattainment and maintenance receptor.\14\ The EPA included 
contribution information resulting from the source-apportionment 
modeling in attachment C to the March 2018 memorandum. For more 
specific information on the modeling and analysis, please see the 2017 
and March 2018 memoranda, the NODA for the preliminary interstate 
transport assessment, and the supporting technical documents included 
in the docket for this action.
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    \14\ As discussed in the March 2018 memorandum, the EPA 
performed source-apportionment model runs for a modeling domain that 
covers the 48 contiguous United States and the District of Columbia, 
and adjacent portions of Canada and Mexico.
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    In the CSAPR and the CSAPR Update, the EPA used a threshold of 1 
percent of the NAAQS to determine whether a given upwind state was 
``linked'' at step 2 of the four-step framework and would therefore 
contribute to downwind nonattainment and maintenance sites identified 
in step 1. If a state's impact did not exceed the 1 percent threshold, 
the upwind state was not ``linked'' to a downwind air quality problem, 
and the EPA therefore concluded the state will not significantly 
contribute to nonattainment or interfere with maintenance of the NAAQS 
in the downwind states. However, if a state's impact exceeded the 1 
percent threshold, the state's emissions were further evaluated in step 
three, taking into account both air quality and cost considerations, to 
determine what, if any, emissions reductions might be necessary to 
address the good neighbor provision.

August and October 2018 Memoranda

    As noted previously, on August 31, 2018, the EPA issued a 
memorandum (the August 2018 memorandum) providing information 
concerning potential contribution thresholds that may be appropriate to 
apply with respect to the 2015 ozone NAAQS in step 2. Consistent with 
the process for selecting the 1 percent threshold in CSAPR and the 
CSAPR Update, the memorandum included analytical information regarding 
the degree to which potential air quality thresholds would capture the 
collective amount of upwind contribution from upwind states to downwind 
receptors for the 2015 ozone NAAQS. The August 2018 memorandum 
indicated that, based on the EPA's analysis of its most recent modeling 
data, the amount of upwind collective contribution captured using a 1 
part per billion (ppb) threshold is generally comparable, overall, to 
the amount captured using a threshold equivalent to 1 percent of the 
2015 ozone NAAQS. Accordingly, the EPA indicated that it may be 
reasonable and appropriate for states to use a 1 ppb contribution 
threshold, as an alternative to the 1 percent threshold, at step 2 of 
the four-step framework in developing their SIP revisions addressing 
the good

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neighbor provision for the 2015 ozone NAAQS.\15\ In addition, on 
October 19, 2018, the EPA issued a memorandum presenting information 
that states may consider as they evaluate the status of monitoring 
sites that the EPA identified as potential maintenance receptors.
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    \15\ See August 2018 memorandum, p. 4.
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    While the March 2018 memorandum presented information regarding the 
EPA's latest analysis of ozone transport following the approaches the 
EPA has taken in prior regional rulemaking actions, the EPA has not 
made any final determinations regarding how states should identify 
downwind receptors with respect to the 2015 ozone NAAQS at step 1 of 
the four-step framework. Rather, the EPA noted that states have 
flexibility in developing their own SIPs to follow different analytical 
approaches than the EPA's, so long as their chosen approach has an 
adequate technical justification and is consistent with the 
requirements of the CAA.

II. State Submission

    On October 25, 2018, the Alaska Department of Environmental 
Conservation (ADEC) made a submission addressing the requirements of 
CAA section 110(a)(2)(D)(i)(I) prongs 1 and 2 for the 2015 ozone 
NAAQS.\16\ The submission provides information supporting the state's 
conclusion that emissions from Alaska do not significantly contribute 
to nonattainment or interfere with maintenance of the 2015 ozone NAAQS 
in any other state. The submission focuses on the amount and sources of 
ozone precursor emissions in the state, trends in monitored ambient 
ozone levels, meteorological conditions, the distance from Alaska to 
the nearest receptors in other states, and the intervening geography 
that isolates Alaska from other states.
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    \16\ Alaska's October 25, 2018 submission addresses all CAA 
sections 110(a)(1) and (2) infrastructure requirements for the 2015 
ozone NAAQS (including interstate transport prongs 1 and 2) and 
includes regulatory updates and permitting rule revisions for 
approval into the SIP. This action addresses the portion of the 
submission related to interstate transport prongs 1 and 2. We intend 
to address the remainder of the submission in separate, future 
actions.
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    The submission states that aggregate anthropogenic ozone precursor 
emissions (nitrogen oxides (NOX) and volatile organic 
compounds (VOCs)) from Alaska sources are very small compared to 
emissions of ozone precursors on a nationwide basis. Specifically, 
Alaska evaluated 2014 National Emissions Inventory data and determined 
that anthropogenic NOX emissions from sources in Alaska make 
up one percent of the national total anthropogenic NOX 
emissions inventoried. In doing the same comparison for VOCs, Alaska 
determined that anthropogenic emissions from Alaska sources make up 
less than one-half percent of total anthropogenic VOC emissions 
nationwide.
    Alaska also included information on monitored ozone levels within 
the state. ADEC has historically monitored ozone at numerous sites in 
and around Anchorage and Fairbanks, the two most-populated areas. The 
submission states that the single highest 8-hour ozone concentration in 
Alaska was recorded at 0.057 ppm on May 11, 2014 at the Fairbanks 
National Core (NCORE) site, which is still well below the 2015 ozone 
standard of 0.070 ppm. The most recent locations for ozone monitoring 
in Alaska are the Fairbanks National Core site and the Palmer site in 
the Anchorage area, both of which have 2015 through 2017 design values 
less than 85 percent of the 2015 ozone NAAQS.\17\ The 2015 through 2017 
design value at the Fairbanks NCore site is 0.043 ppm and the 2015 
through 2017 design value at the Palmer site is 0.044 ppm. The 
submission asserts that ambient ozone measured in Alaska consistently 
trends very low.
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    \17\ Design values below 85 percent of the NAAQS are a factor in 
determining the EPA's minimum ozone monitoring requirements in 40 
CFR part 58, Appendix D.
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    The submission highlights the geographic isolation of the State of 
Alaska. Alaska borders no other state in the United States and the 
intervening geography between Alaska and any other state is 
significant. The southernmost Alaskan border is geographically 
separated from the nearest state, Washington, by hundreds of miles of 
mountainous terrain in British Columbia, Canada. The submission also 
describes meteorological factors that influence potential interstate 
transport from Alaska sources. In the summer months, regional, 
predominant low-pressure wind patterns emanate from the Gulf of Alaska 
in the west and travel inland towards the east, circulating in a 
counterclockwise direction. The submission states these predominant 
low-pressure wind patterns would not generally be expected to transport 
air pollutants from Alaska south to the contiguous United States.
    Alaska's submission points generally to SIP-approved regulations 
that implement the 2015 ozone NAAQS. The submission highlights Alaska's 
SIP-approved stationary source preconstruction permitting program set 
forth in Articles 3 and 5 of Alaska Administrative Code Title 18, 
Environmental Conservation, Chapter 50, Air Quality Control (18 AAC 
50). Alaska's preconstruction permitting program is designed to control 
future potential NOX and VOC emissions from major and minor 
stationary sources in the state. The submission also notes other SIP-
approved rules that serve to limit NOX and VOCs, including 
incinerator emission standards, emission limits for industrial 
processes, and emission limits for fuel burning equipment.

III. EPA Evaluation

    We have employed the four-step interstate transport framework to 
evaluate whether the Alaska SIP meets the requirements of the good 
neighbor provision for the 2015 ozone NAAQS. At step 1, we refer to the 
EPA's March 2018 memorandum to identify downwind air quality problems. 
This memo lists receptors at specific monitoring sites that are 
projected to have problems attaining or maintaining the 2015 ozone 
NAAQS. Specifically, the EPA identified nonattainment receptors as 
those monitoring sites with 2014 through 2016 measured design values 
exceeding the NAAQS that also have projected average 2023 design values 
that exceed the NAAQS. The EPA identified maintenance receptors as 
those monitoring sites with maximum projected 2023 design values 
exceeding the NAAQS. This includes sites with 2014 through 2016 
measured design values below the NAAQS with projected average and 
maximum design values exceeding the NAAQS, and monitoring sites with 
projected average design values below the NAAQS but with projected 
maximum design values exceeding the NAAQS. Receptors identified by the 
EPA are in the states of Arizona, California, Colorado, Connecticut, 
Maryland, Michigan, New York, Texas, and Wisconsin.\18\
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    \18\ See March 2018 memorandum, attachment B.
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    While the EPA's March 2018 memorandum helps to identify potential 
downwind receptors in step 1, it does not inform whether Alaska is 
sufficiently linked to those receptors, as is required in step 2 of the 
EPA's four-step framework. The EPA did not include Alaska in the state-
level ozone source-apportionment modeling that estimated the expected 
impact from each state to each nonattainment and maintenance 
receptor.\19\
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    \19\ See March 2018 memorandum, attachment C.
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    In the absence of such modeling and state level source 
apportionment data at step 2, we have used a ``weight of

[[Page 26045]]

evidence'' approach to evaluate factors that together help determine 
whether Alaska emissions are sufficiently linked to potential 
nonattainment or maintenance receptors in other states. The factors 
evaluated for purposes of this proposed action include emissions 
inventory data, monitoring trends, geography, meteorology, and SIP-
approved provisions that limit current and future emissions of ozone 
precursors, as described in the following paragraphs.

Emissions Inventory Data

    According to the most recent, publicly-available census data, 
Alaska's population is less than a million people (737,438).\20\ 
Stationary and mobile source emissions are related, in part, to an 
area's population. As stated in the submission, and confirmed by 2014 
National Emissions Inventory data, Alaska's stationary and mobile 
source emissions of NOX and VOCs as precursors to ozone 
formation comprise a very small fraction of emissions nationwide, 
totaling just one percent and one-half percent, respectively.\21\ 
Compared to other states in the northwest, Alaska's NOX 
emissions are in the middle of the range, while Alaska's VOC emissions 
are low.
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    \20\ United States Census Bureau population estimate for Alaska, 
July 1, 2018, published at: https://www.census.gov/quickfacts/fact/table/ak,US/PST045218.
    \21\ ``Biogenic sources'' and ``Fire sources'' are not included. 
See EPA 2014 National Emissions Inventory Report, published at 
https://gispub.epa.gov/neireport/2014/.

                      Table 1--2014 NEI Stationary and Mobile Source NOX and VOC Emissions
                                                   [Tons] \22\
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            Pollutant               Nationwide        Alaska           Idaho          Oregon        Washington
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NOX.............................      12,233,224         127,194          81,135         125,626         234,050
VOCs............................      12,388,288          63,408          86,332         134,431         241,561
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Monitoring Trends

    In addition to emissions inventory data, we have evaluated historic 
ozone monitoring data within Alaska. ADEC has monitored ozone in 
Anchorage and Fairbanks over the last 10 years. The National Park 
Service also monitors for ozone at Denali National Park.\23\ Minimum 
monitoring requirements for ozone are established in 40 CFR part 58, 
Appendix D, and make use of population data and design value history to 
determine the minimum number of ozone monitors that are required in 
areas of each state.\24\ The following table shows ozone design values 
calculated from 2010 to the present. All are well below the 2015 ozone 
NAAQS (0.070 ppm).
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    \22\ Ibid.
    \23\ Clean Air Status and Trends Network (CASTNET).
    \24\ 40 CFR part 58, Appendix D, Network Design Criteria for 
Ambient Air Quality Monitoring, Table D-2. The 2018 Alaska 
monitoring network plan was approved by the EPA on October 19, 2018. 
The EPA approval letter is in the docket for this action.

                                                        Table 2--Alaska Ozone Design Value Trends
                                                                       [ppm] \25\
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           Site ID                      Location             2010-2012       2011-2013       2012-2014       2013-2015       2014-2016       2015-2017
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020200018                      Anchorage, Garden........           0.045  ..............  ..............  ..............  ..............  ..............
020680003                      Denali National Park.....           0.052           0.052           0.053           0.054           0.053           0.050
020900034                      Fairbanks, NCORE.........  ..............  ..............           0.046           0.045           0.041           0.043
021700012                      Anchorage, Palmer........  ..............  ..............  ..............  ..............  ..............           0.044
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Geography and Meteorology

    Another factor for consideration is that Alaska is geographically 
vast and isolated from any other state in the United States. Alaska is 
over 586,000 square miles in area and shares no borders with other 
states.\26\ Alaska is bordered to the east by the Yukon Territory and 
British Columbia, Canada. To the south is the Gulf of Alaska and the 
Pacific Ocean. To the west is the Bering Sea, Bering Strait, and 
Chukchi Sea. The Arctic Ocean lies to the north. Alaska is distant from 
the nonattainment and maintenance receptors identified in the EPA's 
March 2018 memorandum. The closest identified nonattainment receptor is 
in Sacramento, California (Site ID 60675003) and the closest identified 
maintenance receptor is also in Sacramento (Site ID 60670012). 
California is over 1000 miles from Alaska's southernmost border and the 
intervening topography in Alaska and British Columbia, Canada are 
varied and includes mountainous and complex terrain.\27\ Geographically 
situated between Alaska and California are the states of Washington and 
Oregon. Each intervening state has equivalent or higher ozone precursor 
emissions compared to Alaska,\28\ and each has been determined by the 
EPA to contribute less than 1 percent to identified receptors in any 
other state, including California.\29\
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    \25\ EPA 2017 Ozone Design Value Report, Table 6, Monitor 
Trends, https://www.epa.gov/air-trends/air-quality-design-values.
    \26\ 2015Alaska Air Quality Monitoring Network Assessment, p. 8, 
published at http://dec.alaska.gov/air/air-monitoring/network-assessments.
    \27\ Ibid, p. 10.
    \28\ See ``Table 1: 2014 NEI Stationary and Mobile Source 
NOX and VOC Emissions (tons)'' in the preceding 
paragraph.
    \29\ Washington and Oregon's modeled contribution to the 
Sacramento nonattainment receptor (Site ID 60675003) is 0.14 ppb and 
0.45 ppb, respectively. Washington and Oregon's modeled contribution 
to the Sacramento maintenance receptor (Site ID 60670012) is 0.20 
ppb and 0.57 ppb, respectively. See March 2018 memorandum, 
attachment C.
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    Meteorology is also a factor that can limit potential transport of 
emissions from Alaska to identified receptors. According to Alaska's 
submission and the 2015 Alaska Air Quality Monitoring Network 
Assessment, weather in Alaska during the summer months is influenced by 
the jet stream and low-pressure systems that tend to move weather 
patterns from south-central Alaska up into the Interior, not south to 
the contiguous United States.\30\ The summer months are when ozone 
levels are generally higher, and that holds true

[[Page 26046]]

at the Sacramento, California nonattainment and maintenance receptors, 
which are those EPA-identified receptors closest to Alaska, discussed 
in the previous paragraph.\31\
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    \30\ Ibid, p. 23.
    \31\ The high ozone season is May through October in the 
Sacramento area. Sacramento Regional 8-hour Ozone Attainment and 
Reasonable Further Progress plan, Chapter 1, page 1-1, which can be 
found at http://www.airquality.org/businesses/air-quality-plans/federal-planning.
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Alaska SIP

    It is helpful to review a state's existing SIP-approved regulations 
as part of a weight of evidence analysis. Therefore, we have evaluated 
the current federally-approved Alaska SIP and those rules in the SIP 
that are designed to limit emissions of NOX and VOCs from 
existing and future sources. Alaska generally regulates emissions of 
NOX and VOCs through its SIP-approved stationary source 
preconstruction permitting programs, set forth in Articles 3 and 5 of 
18 AAC 50, in addition to other regulations approved into the SIP and 
described in this section. Stationary source preconstruction permitting 
is known as new source review (NSR) and establishes requirements based 
on a source's size and location, among other things. New and modified 
major stationary sources located in designated nonattainment areas are 
subject to nonattainment NSR permitting requirements (NNSR) for the 
nonattainment pollutant. New and modified major stationary sources in 
designated attainment and unclassifiable areas are subject to 
prevention of significant deterioration permitting requirements (PSD). 
Alaska's SIP approved NNSR and PSD programs are found in Article 3 of 
18 AAC 50. Minor new and modified stationary sources are regulated by 
Alaska's SIP-approved minor NSR program found in Article 5 of 18 AAC 
50.
    All of Alaska is designated ``attainment/unclassifiable'' for the 
2015 ozone NAAQS.\32\ Therefore, with respect to ozone precursor 
emissions, stationary sources seeking to construct or modify in Alaska 
are subject to PSD and minor NSR, depending on the size of the source. 
The Alaska PSD permitting program in Article 3 of 18 AAC 50 references 
a suite of regulations approved into the Alaska SIP and makes use of 
certain federal PSD requirements, set forth in the Code of Federal 
Regulations (CFR), and incorporated by reference into the Alaska SIP in 
18 AAC 50.040. See 40 CFR 52.96. The EPA most recently approved updates 
and revisions to the Alaska PSD permitting program on August 28, 2017 
(82 FR 40712). The current SIP-approved Alaska PSD permitting program 
incorporates by reference specific federal requirements in 40 CFR 
52.21, 40 CFR 51.166, and 40 CFR part 51, Appendix W, as of July 1, 
2017. The program has been updated for the 2015 ozone NAAQS and 
regulates NOX and VOCs as precursors to ozone formation, 
consistent with the EPA's implementing regulations at 40 CFR 51.166.
---------------------------------------------------------------------------

    \32\ 40 CFR 81.302.
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    Turning to minor sources, Article 5 of 18 AAC 50 requires pre-
construction permitting for subject new and modified minor stationary 
sources. SIP-approved minor NSR programs and revisions to such programs 
must be consistent with the EPA's implementing regulations at 40 CFR 
51.160 through 51.164. Alaska's minor NSR program was originally 
approved into the Alaska SIP on July 5, 1983 (48 FR 30623). We have 
approved subsequent revisions, most recently on August 28, 2017 (82 FR 
40712). Both Alaska's PSD and minor NSR programs are designed to limit 
potential future emissions of NOX and VOCs.
    In addition to permitting requirements, Alaska's SIP contains other 
rules that also serve to limit NOX and VOCs. These rules 
include incinerator emission standards (18 AAC 50.050) and emission 
limits for industrial processes and fuel burning equipment (18 AAC 
50.055).
    Based on the factors evaluated and discussed in this proposal and 
supporting material in the docket for this action, the EPA believes it 
is reasonable to conclude that emissions from Alaska are not likely to 
be linked to nonattainment and maintenance receptors in the contiguous 
United States. We propose to find that Alaska's SIP contains adequate 
provisions that are designed to limit future potential NOX 
and VOC emissions, and therefore, the state is unlikely to be linked to 
downwind receptors in the future. Accordingly, we have stopped our 
evaluation at step 2 of the four-step framework.

IV. Proposed Action

    As discussed in section II in this preamble, Alaska concluded that 
emissions from sources in the state will not significantly contribute 
to nonattainment or interfere with maintenance of the 2015 ozone NAAQS 
in any other state. The EPA's evaluation, discussed in section III in 
this preamble, confirms this finding. We are proposing to approve the 
Alaska SIP as meeting CAA section 110(a)(2)(D)(i)(I) requirements for 
the 2015 ozone NAAQS.

V. Statutory and Executive Order Reviews

    Under the CAA, the Administrator is required to approve a SIP 
submission that complies with the provisions of the CAA and applicable 
federal regulations. 42 U.S.C. 7410(k); 40 CFR 52.02(a). Thus, in 
reviewing SIP submissions, the EPA's role is to approve state choices, 
provided they meet the criteria of the CAA. Accordingly, this proposed 
action merely approves state law as meeting federal requirements and 
does not impose additional requirements beyond those imposed by state 
law. For that reason, this proposed action:
     Is not a ``significant regulatory action'' subject to 
review by the Office of Management and Budget under Executive Orders 
12866 (58 FR 51735, October 4, 1993) and 13563 (76 FR 3821, January 21, 
2011);
     Is not an Executive Order 13771 (82 FR 9339, February 2, 
2017) regulatory action because SIP approvals are exempted under 
Executive Order 12866;
     Does not impose an information collection burden under the 
provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.);
     Is certified as not having a significant economic impact 
on a substantial number of small entities under the Regulatory 
Flexibility Act (5 U.S.C. 601 et seq.);
     Does not contain any unfunded mandate or significantly or 
uniquely affect small governments, as described in the Unfunded 
Mandates Reform Act of 1995 (Pub. L. 104-4);
     Does not have Federalism implications as specified in 
Executive Order 13132 (64 FR 43255, August 10, 1999);
     Is not an economically significant regulatory action based 
on health or safety risks subject to Executive Order 13045 (62 FR 
19885, April 23, 1997);
     Is not a significant regulatory action subject to 
Executive Order 13211 (66 FR 28355, May 22, 2001);
     Is not subject to requirements of Section 12(d) of the 
National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272 
note) because it does not involve technical standards; and
     Does not provide the EPA with the discretionary authority 
to address, as appropriate, disproportionate human health or 
environmental effects, using practicable and legally permissible 
methods, under Executive Order 12898 (59 FR 7629, February 16, 1994).
    In addition, the SIP is not approved to apply on any Indian 
reservation land or in any other area where the EPA or an Indian tribe 
has demonstrated that a

[[Page 26047]]

tribe has jurisdiction. In those areas of Indian country, the rule does 
not have tribal implications and will not impose substantial direct 
costs on tribal governments or preempt tribal law as specified by 
Executive Order 13175 (65 FR 67249, November 9, 2000).

List of Subjects in 40 CFR Part 52

    Environmental protection, Air pollution control, Incorporation by 
reference, Intergovernmental relations, Lead, Nitrogen dioxide, Ozone, 
Particulate matter, Reporting and recordkeeping requirements, Sulfur 
oxides, Volatile organic compounds.

    Authority: 42 U.S.C. 7401 et seq.

    Dated: May 21, 2019.
Chris Hladick,
Regional Administrator, Region 10.
[FR Doc. 2019-11764 Filed 6-4-19; 8:45 am]
BILLING CODE 6560-50-P