[Federal Register Volume 83, Number 126 (Friday, June 29, 2018)]
[Proposed Rules]
[Pages 30622-30626]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2018-14067]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R06-OAR-2017-0435; FRL-9979-25-Region 6]


Approval and Promulgation of Implementation Plans; Arkansas; 
Interstate Transport Requirements for the 2012 PM2.5 NAAQS and 
Definition Update

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: Pursuant to the Clean Air Act (CAA or Act), the Environmental 
Protection Agency (EPA) is proposing to approve portions of the 
Arkansas State Implementation Plan (SIP) submittal addressing the CAA 
requirement that SIPs address the potential for interstate transport of 
air pollution to significantly contribute to nonattainment or interfere 
with maintenance of the 2012 fine particulate matter (PM2.5) 
National Ambient Air Quality Standards (NAAQS) in other states. EPA is 
proposing to determine that emissions from Arkansas sources do not 
contribute significantly to nonattainment in, or interfere with 
maintenance by, any other state with regard to the 2012 
PM2.5 NAAQS. The EPA is also proposing to approve a revision 
to update incorporation by reference of NAAQS germane to this proposed 
action.

DATES: Written comments must be received on or before July 30, 2018.

ADDRESSES: Submit your comments, identified by Docket Number EPA-R06-
OAR-2017-0435, at http://www.regulations.gov or via email to 
[email protected]. 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 submit electronically any information you consider to be 
Confidential Business Information (CBI) or other information whose 
disclosure 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, please contact Sherry Fuerst, 214-665-
6454, [email protected]. For the full EPA public comment policy, 
information about CBI or multimedia submissions, and general guidance 
on making effective comments, please visit http://www2.epa.gov/dockets/commenting-epa-dockets.
    Docket: The index to the docket for this action is available 
electronically at www.regulations.gov and in hard copy at the EPA 
Region 6, 1445 Ross Avenue, Suite 700, Dallas, Texas. While all 
documents in the docket are listed in the index, some information may 
be publicly available only at the hard copy location (e.g., copyrighted 
material), and some may not be publicly available at either location 
(e.g., CBI).

FOR FURTHER INFORMATION CONTACT: Sherry Fuerst, 214-665-6454, 
[email protected]. To inspect the hard copy materials, please 
schedule an appointment with Ms. Fuerst or Mr. Bill Deese at 214-665-
7253.

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

[[Page 30623]]

I. Background

A. The PM2.5 NAAQS and Interstate Transport of Air Pollution

    Under Section 109 of the CAA, we establish NAAQS to protect human 
health and public welfare. In 2012, we established a new annual NAAQS 
for PM2.5 of 12 micrograms per cubic meter ([mu]g/m\3\), (78 
FR 3085, January 15, 2013). The CAA requires states to submit, within 
three years after promulgation of a new or revised standard, SIPs 
meeting the applicable ``infrastructure'' elements of sections 
110(a)(1) and (2). One of these applicable infrastructure elements, CAA 
section 110(a)(2)(D)(i), requires SIPs to contain provisions to 
prohibit certain adverse air quality effects on neighboring states due 
to interstate transport of pollution. There are four sub-elements 
within CAA section 110(a)(2)(D)(i). This action reviews how the first 
two sub-elements contained in CAA section 110(a)(2)(D)(i)(I) were 
addressed in an infrastructure SIP submission from Arkansas for the 
2012 PM2.5 NAAQS. These sub-elements require that each SIP 
for a new or revised NAAQS contain adequate provisions to prohibit any 
source or other type of emissions activity in one state that will 
``contribute significantly to nonattainment'' or ``interfere with 
maintenance'' of the applicable air quality standard in any other 
state.
    The EPA has addressed the interstate transport requirements of CAA 
section 110(a)(2)(D)(i)(I) with respect to PM2.5 in several 
past regulatory actions. In 2011, we promulgated the Cross-State Air 
Pollution Rule (CSAPR, 76 FR 48208, August 8, 2011) in order to address 
the obligations of states--and of the EPA when states have not met 
their obligations--under CAA section 110(a)(2)(D)(i)(I) to prohibit air 
pollution contributing significantly to nonattainment in, or 
interfering with maintenance by, any other state with regard to several 
NAAQS, including the 1997 annual and 2006 24-hour PM2.5 
NAAQS.\1\ In that rule, we considered states linked to downwind 
nonattainment or maintenance receptors \2\ if they were projected by 
air quality modeling to contribute more than the threshold amount (1% 
of the standard) of PM2.5 pollution for the 1997 and 2006 
PM2.5 NAAQS (76 FR 48208, 48239-43). The EPA has not 
established a threshold amount for the 2012 PM2.5 NAAQS. In 
2016 we provided an informational memorandum (the 2016 memo) about the 
steps states should follow as they develop and review SIPs that address 
this provision of the CAA for the 2012 PM2.5 NAAQS.\3\
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    \1\ Federal Implementation Plans; Interstate Transport of Fine 
Particulate Matter and Ozone and Correction of SIP Approvals, 76 FR 
48207 (August 8, 2011) (codified as amended at 40 CFR 52.38 and 
52.39 and 40 CFR part 97).
    \2\ Nonattainment or maintenance receptors are monitors 
projected to have air quality problems.
    \3\ Information on the Interstate Transport ``Good Neighbor'' 
Provision for the 2012 Fine Particulate Matter National Ambient Air 
Quality Standards under Clean Air Act Section 110(a)(2)(D)(i)(I) 
March 17, 2016 from Stephen D. Page.
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B. Arkansas SIP Submittal Pertaining to the 2012 PM2.5 NAAQS and 
Interstate Transport of Air Pollution

    On March 24, 2017, Arkansas submitted a SIP revision to address the 
requirements of CAA section 110(a)(2)(D)(i)(I) for the 2012 
PM2.5 NAAQS. The submittal stated that the State had 
adequate provisions to prohibit air pollutant emissions from within the 
State that significantly contribute to nonattainment or interfere with 
maintenance of the 2012 PM2.5 NAAQS stating, ``Past 
contribution modeling by EPA for the 2006 PM2.5 NAAQS, 
included in `Air Quality Modeling Final Rule Technical Support 
Document' published in June 2001 to support the Final Cross-State Air 
Pollution Rule (CSAPR) (76 FR 48208), demonstrated that Arkansas did 
not significantly contribute to nonattainment or interfere with 
maintenance of the annual PM2.5. NAAQS that was set in 1997 
and retained in 2006.'' \4\ Arkansas's largest contribution to 
nonattainment for the 2006 annual PM2.5 NAAQS was 0.1 [mu]g/
m\3\ and Arkansas's largest downwind contribution to maintenance of the 
2006 PM2.5 annual standard was 0.04 [mu]g/m\3\. Not only are 
both of these values below the 1% significance threshold for the annual 
PM2.5 NAAQS retained in 2006 (15 [mu]g/m\3\), they are also 
below 1% of the 2012 PM2.5 NAAQS value of 12 [mu]g/m\3\.''
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    \4\ Air Quality Modeling Final Rule Technical Support Document, 
June 2011 http://www.epa.gov/airtransport/CSAPR/pdfs/AQModeling.pdf.
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    We previously approved the portions of Arkansas's 2006 
PM2.5 NAAQS i-SIP which addressed the requirements that 
emissions within Arkansas be prohibited from contributing to the 
nonattainment or interfere with maintenance of the NAAQS in other 
states (sub-elements 1 and 2). 78 FR 53269 (August 29, 2013). Based on 
our evaluation of the State's submission discussed below, we propose to 
approve the March 24, 2017 submittal intended to demonstrate that the 
SIP meets the requirements of CAA section 110(a)(2)(D)(i)(I) for the 
2012 PM2.5 NAAQS.

C. Revisions to the Arkansas SIP Definitions and National Ambient Air 
Quality Standards List

    Included in the March 24, 2017 submission were updates to 
Regulation 19, Chapter 2 and Appendix B (Regulations of the Arkansas 
Plan of Implementation for Air Pollution Control) of the Arkansas Code 
Annotated Sec.  8-4-201. We are proposing to approve the revised 
definition of ``National Ambient Air Quality Standards'' in Chapter 2 
that changes the effective date to January 15, 2013. We also are 
proposing to approve the changes in Appendix B under ``Particle 
Pollution, PM2.5.'' that reflect the update and apply the 
Chapter 2 definition to all Chapters of Regulation 19. Please see the 
Technical Support Document (TSD) for additional information and 
evaluation below.

II. The EPA's Evaluation

A. Pertaining to 110(a)(2)(D)(i)(I) for the 2012 PM2.5 NAAQS

    As stated above, Section 110(a)(2)(D)(i) requires SIPs to include 
adequate provisions prohibiting any source or other type of emissions 
activity in one state that will (I) contribute significantly to 
nonattainment, or interfere with maintenance of the NAAQS in another 
state, and (II) interfere with measures required to prevent significant 
deterioration of air quality, or to protect visibility in another 
state. This action addresses only CAA Section 110(a)(2)(D)(i)(I).
    EPA issued the 2016 memo about the steps states should follow and 
we will be following the framework outlined in the memo for our 
evaluation. The 2016 EPA memo outlined the four-step framework EPA has 
historically used to evaluate interstate transport under section 
110(a)(2)(D)(i)(I), including the EPA's CSAPR.
    (1) Identification of potential downwind nonattainment and 
maintenance receptors;
    (2) Identification of upwind states contributing to downwind 
nonattainment and maintenance receptors;
    (3) For states identified as contributing to downwind air quality 
problem, identification of upwind emissions reductions necessary to 
prevent upwind states from significantly contributing to nonattainment 
or interfering with maintenance of receptors, and;
    (4) For states that are found to have emissions that significantly 
contribute to non-attainment or interfere with maintenance downwind, 
reducing the

[[Page 30624]]

identified upwind emissions through adoption of permanent and 
enforceable measures.
    Based on this approach, the potential receptors are outlined in 
Table 1 in the memo. Most of the potential receptors are in California, 
located in the San Joaquin Valley or South Coast nonattainment areas. 
However, there is also one potential receptor in Shoshone County, 
Idaho, and one potential receptor in Allegheny County, Pennsylvania.
    The 2016 memo did note that because of data quality problems 
nonattainment and maintenance projections were not done for all or 
portions of Florida, Illinois, Idaho, Tennessee and Kentucky. After 
issuance of the memo, data quality problems were resolved for Idaho, 
Tennessee, Kentucky and most of Florida, identifying no additional 
potential receptors, with those areas having design values (DV) below 
the 2012 PM2.5 NAAQS and expected to maintain the NAAQS due 
to downward emission trends for NOX and SO2 
(www.epa.gov/air-trends/air-quality-design-values and www.epa.gov/air-emissions-inventories/air-pollutant-emissions-trends-data). Florida 
certified in March 2018 its 2017 PM2.5 ambient air data for 
the counties in Florida that had had 2009-2013 data gaps, allowing us 
to develop 2015-2017 preliminary design values. The preliminary design 
values indicate the highest value is 8 [mu]g/m\3\ in Florida well below 
the NAAQS. For these reasons, we find that none of the counties in 
Florida with monitoring gaps between 2009-2013 should be considered 
either nonattainment or maintenance receptors for the 2012 
PM2.5 NAAQS, based on the 2015-2017 preliminary DV. 
Therefore, as of April 2018, only Illinois still has data quality 
issues preventing projections of nonattainment and maintenance 
receptors. As a result, Illinois will be evaluated below to determine 
if they have potential nonattainment or maintenance receptors for 2012 
PM2.5 NAAQS.
    For ``Step 1'' of this evaluation, the areas identified as 
``potential downwind nonattainment and maintenance receptors'' are:
     Seventeen potential receptors in California, located in 
the San Joaquin Valley or South Coast nonattainment areas;
     Shoshone County, Idaho;
     Allegheny County, Pennsylvania;
     All of Illinois
    As stated above, ``Step 2'' is the identification of states 
contributing to downwind nonattainment and maintenance receptors, such 
that further analysis is required to identify necessary upwind 
reductions. For this step, we will be specifically determining if 
Arkansas emissions contribute to downwind nonattainment and maintenance 
receptors.
    Each of the potential receptors is discussed below, with a more in-
depth discussion provided in the TSD for this action. For additional 
information, links to the documents relied upon for this analysis can 
be found throughout the document, more information is available in the 
TSD and the documents can be found in the docket for this action.
California
    As described in our TSD, our analysis shows that Arkansas's 
PM2.5 emissions and/or PM2.5 precursors do not 
significantly impact the California potential receptors identified in 
the memo. In our analysis, we found specifically that the majority of 
the emissions impacting PM2.5 levels in California are 
directly emitted PM2.5 and/or PM2.5 precursors 
from within the state, and that meteorological and topographic 
conditions serve as barriers to transport from Arkansas. We note that 
air quality designations are not relevant to our evaluation of 
interstate transport, however, the analysis developed for the 2012 
annual PM2.5 NAAQS designations process provides an in depth 
evaluation of factors critical in evaluating transport of 
PM2.5 and PM2.5 precursors, including evaluation 
of local emissions, wind speed and direction, topographical and 
meteorological conditions and seasonal variations recorded at the 
monitors, which all support the conclusion that Arkansas's 
PM2.5 and PM2.5 precursors do not significantly 
contribute to nonattainment or interfere with maintenance of the 
California potential receptors. Furthermore, Arkansas is more than 
1,700 miles to the east and generally downwind of the California 
receptors.\5\
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    \5\ California: Imperial County, Los Angeles-South Coast Air 
Basin, Plumas County, San Joaquin Valley Area Designations for the 
2012 Primary Annual PM2.5 National Ambient Air Quality 
Standard Technical Support Document https://www.regulations.gov/document?D=EPA-HQ-OAR-2012-0918-0330.
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    For these reasons, we propose to find that Arkansas does not 
significantly contribute to nonattainment, nor will it interfere with 
maintenance of the 2012 PM2.5 NAAQS for California.
Shoshone County, Idaho
    As discussed in the TSD, our analysis shows that Arkansas's 
PM2.5 emissions and/or PM2.5 precursors do not 
significantly impact the Idaho potential receptor identified in the 
memo. In our analysis, we found specifically that the majority of the 
emissions impacting PM2.5 levels, came during the winter 
time and could be attributed to residential wood combustion. The 
analysis developed for the 2012 annual PM2.5 NAAQS 
designations process provide an in depth evaluation of factors that are 
useful in evaluating transport of PM2.5 and PM2.5 
precursors, including evaluation of local emissions, wind speed and 
direction, topographical and meteorological conditions and seasonal 
variations recorded at the monitor, which all support the conclusion 
that Arkansas PM2.5 and PM2.5 precursors do not 
significantly contribute to nonattainment nor interfere with 
maintenance of the Idaho potential receptor.\6\ Furthermore, Arkansas 
is to the southeast and downwind of this receptor.
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    \6\ Idaho: West Silver Valley Nonattainment Area- 2012 Primary 
Annual PM2.5 National Ambient Air Quality Standard 
Technical Support Document. Prepared by EPA Region 10.
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    For these reasons, we propose to find that Arkansas does not 
significantly contribute to nonattainment, nor will it interfere with 
maintenance of the 2012 PM2.5 NAAQS for Shoshone, Idaho.
Allegheny County, Pennsylvania
    As discussed in the TSD, our analysis shows that Arkansas's 
PM2.5 emissions and/or PM2.5 precursors do not 
significantly impact the Allegheny County, Pennsylvania (Liberty 
monitor) potential receptor identified in the memo. In our analysis, we 
found that there were strong local influences throughout Allegheny 
County and contributions from nearby states that contributed to its 
nonattainment for both the 1997 and 2006 PM2.5 NAAQS. 
Contributors to the Liberty monitor in Allegheny County, Pennsylvania 
in recent years, have taken steps to improve air quality which will 
likely bring the monitor into compliance with the 2012 PM2.5 
annual NAAQS by the 2021 attainment date.
    Another compelling fact is that in previous modeling, nonattainment 
in Allegheny County, Pennsylvania was linked to significant 
contributions from other states.\7\ Arkansas was analyzed in this 
modeling, and emissions from Arkansas were not linked to Allegheny 
County.
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    \7\ Air Quality Modeling for 2011 Cross-State Air Pollution Rule 
(CSAPR) (76 FR 48207, August 8, 2011).
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    For these reasons, we propose to find that Arkansas does not 
significantly contribute to nonattainment, nor will it interfere with 
maintenance of the 2012 PM2.5 NAAQS for Allegany County, 
Pennsylvania.

[[Page 30625]]

Illinois
    Due to ambient monitoring data gaps in the 2009-2013 data that 
would have been used to identify potential PM2.5 
nonattainment and maintenance receptors in Illinois, the modeling 
analysis of potential receptors could not be completed for the state. 
As a result, the entire state is considered unclassifiable.
    Arkansas was included in the CSAPR modeling analysis for the 1997 
PM2.5 NAAQS. This analysis showed Illinois did have a 
nonattainment receptor identified through the CSAPR modeling analysis 
for the 1997 PM2.5 NAAQS. The receptor was in Madison, 
Illinois, located near St. Louis, Missouri. The modeling did not, 
however, show a linkage for nonattainment or maintenance between 
Arkansas and Illinois meaning Arkansas' impact was estimated to be less 
than 1% of the 1997 NAAQS at the Madison, Illinois receptor. While this 
modeling does not directly address the 2012 standard it is indicative 
that Arkansas emissions are unlikely to impact attainment or 
maintenance receptors in Illinois.
    As further evidence, recent 3-year averages for the monitors in 
Madison, Illinois have shown downward trends. There are three active 
monitors in Madison. The 3-year averages for the monitors are shown in 
Table 1 below. Because of data gaps, the data cannot be used to 
establish a valid design value but can be used to show a downward 
trend. Also, as noted in the TSD for this action, Illinois has been 
collecting valid data for 2015 and 2016. This data, while not a 
complete three-year period indicates that air quality in Illinois is 
meeting the 2012 p.m. 2.5 NAAQS.

               Table 1--Annual Standard 3-Year Averages ([mu]g/m3) for Madison, Illinois Monitors
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                           Monitor No.                               2012-2014       2013-2015       2014-2016
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171191007.......................................................            12.9            11.6            10.8
171192009.......................................................            10.4             9.7             9.4
171193007.......................................................            12.5            10.8            10.1
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    For these reasons, we propose that Arkansas will not significantly 
contribute to nonattainment, nor will it interfere with maintenance of 
the 2012 PM2.5 NAAQS in Illinois.
    Since we determined that Arkansas's SIP includes provisions 
prohibiting any source or other type of emissions activity from 
contributing significantly to nonattainment in, or interfering with 
maintenance of the NAAQS, in another state, steps 3 and 4 of this 
evaluation are not necessary.
    In conclusion, based on our review of the potential receptors 
presented in the March 17, 2016 informational memo, an evaluation 
identifying likely emission sources affecting these potential 
receptors, and the 2014 base case modeling in CSAPR final rule, we 
propose to determine that emissions from Arkansas sources will not 
contribute significantly to nonattainment in, nor interfere with 
maintenance by, any other state with regard to the 2012 annual 
PM2.5 NAAQS.

B. Pertaining to Revisions to SIP Definition and the National Ambient 
Air Quality Standards List

    The ADEQ submitted a collection of revisions to the Arkansas SIP on 
March 24, 2017. Included in these revisions is an update to the 
Arkansas SIP definition for the National Ambient Air Quality Standards. 
The definition in Chapter 2 of Regulation 19 updates the incorporation 
by reference date included in 40 CFR part 50 from July 27, 2012 to 
January 15, 2013. The changes in the revised Appendix B to Regulation 
19 titled the ``National Ambient Air Quality Standards List'' reflect 
the definition update and applies it to all Chapters of Regulation 19.

III. Proposed Action

    We have determined that the revisions submitted on March 24, 2017, 
were developed in accordance with the CAA and EPA's regulations. 
Therefore, under section 110 of the Act, the EPA proposes approval of 
the following revisions to the Arkansas SIP:
     The portion of the Arkansas SIP submittal, pertaining to 
interstate transport of air pollution demonstrating emissions from 
Arkansas will not significantly contribute to nonattainment or 
interfere with maintenance of the 2012 PM2.5 NAAQS in any 
other state pursuant to the requirements of CAA section 
110(a)(2)(D)(i)(I).
     The portion of the Arkansas SIP submittal where the 
definition of National Ambient Air Quality Standards in Regulation 19, 
Chapter 2 is revised to be the effective date of January 15, 2013 and 
Appendix B to Regulation 19, ``National Ambient Air Quality Standards 
List'' at ``Particle Pollution, PM2.5'' as consistent with 
the CAA.

IV. Incorporation by Reference

    In this action, we are proposing to include in a final rule 
regulatory text that includes incorporation by reference. In accordance 
with the requirements of 1 CFR 51.5, we are proposing to incorporate by 
reference revisions to the Arkansas regulations as described in the 
Proposed Action section above. We have made, and will continue to make, 
these documents generally available electronically through 
www.regulations.gov and in hard copy at the EPA Region 6 office (please 
contact Sherry Fuerst, 214-665-6454, [email protected] for more 
information).

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 Act 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 that they meet the criteria of the CAA. Accordingly, this 
action merely proposes to approve state law as meeting Federal 
requirements and does not impose additional requirements beyond those 
imposed by state law. For that reason, this 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

[[Page 30626]]

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 application of those requirements would be inconsistent 
with the CAA; and
     Does not provide 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 EPA or an Indian tribe has 
demonstrated that a tribe has jurisdiction. In those areas of Indian 
country, the proposed 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, Particulate matter.

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

    Dated: June 26, 2018.
David Gray,
Acting Regional Administrator, Region 6.
[FR Doc. 2018-14067 Filed 6-28-18; 8:45 am]
 BILLING CODE 6560-50-P