[Federal Register Volume 83, Number 226 (Friday, November 23, 2018)]
[Proposed Rules]
[Pages 59350-59352]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2018-25477]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 81

[EPA-R06-OAR-2018-0624; FRL-9986-54-Region 6]


Air Quality Designation for the 2010 Sulfur Dioxide (SO2) Primary 
National Ambient Air Quality Standard; Arkansas; Redesignation of the 
Independence County Area

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: On April 20, 2018, the State of Arkansas (AR), through the 
Arkansas Department of Environmental Quality (ADEQ) submitted a request 
for the Environmental Protection Agency (EPA) to assess new available 
information and redesignate the Independence County, AR unclassifiable 
area (hereinafter referred to as the ``County'' or ``Area'') for the 
2010 sulfur dioxide (SO2) primary national ambient air 
quality standard (NAAQS) to attainment/unclassifiable. The EPA is 
proposing that it now has sufficient information to determine that the 
Area is attaining the 2010 SO2 primary NAAQS, and, 
therefore, is proposing to approve the State's request and redesignate 
the Area to attainment/unclassifiable for the 2010 primary 
SO2 NAAQS.

DATES: Comments must be received on or before December 24, 2018.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-R06-
OAR-2018-0624 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 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, 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: Mr. Ruben Casso, (214) 665-6763, 
[email protected]. To inspect the hard copy materials, please 
schedule an appointment with Mr. Casso.

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

I. Background

    The Clean Air Act (CAA or Act) establishes a process for air 
quality management through the establishment and implementation of the 
NAAQS. After the promulgation of a new or revised NAAQS, EPA is 
required to designate all areas of the country, pursuant to section 
107(d)(1) of the CAA. For the 2010 SO2 primary NAAQS, 
designations were based on the EPA's application of the nationwide 
analytical approach to, and technical assessment of, the weight of 
evidence for each area, including but not limited to available air 
quality monitoring data and air quality modeling results. The EPA 
issued updated designations guidance through a March 20, 2015, 
memorandum from Stephen D. Page, Director, U.S. EPA, Office of Air 
Quality Planning and Standards, to Air Division Directors, U.S. EPA 
Regions 1-10 titled, ``Updated Guidance for Area Designations for the 
2010 Primary Sulfur Dioxide National Ambient Air Quality Standard,'' 
which contains the factors the EPA intends to evaluate in determining 
the appropriate designations and associated boundaries, including: (1) 
Air quality

[[Page 59351]]

characterization via ambient monitoring or dispersion modeling results; 
(2) emissions-related data; (3) meteorology; (4) geography and 
topography; and (5) jurisdictional boundaries. The guidance also 
references the EPA's non-binding Monitoring Technical Assistance 
Document (Monitoring TAD) and Modeling Technical Assistance Document 
(Modeling TAD),\1\ which contain scientifically sound recommendations 
on how air agencies should conduct such monitoring or modeling.
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    \1\ ``Sulfur Dioxide (S02) National Ambient Air 
Quality Standards Designations Modeling Technical Assistance 
Document''. August 2016 draft https://www.epa.gov/sites/production/files/2016-0706/documents/areadesignso2modelingtad.pdf. Note. the 
EPA released earlier drafts of this document in May and 2013 and 
February 2016.
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    Entergy Corporation Independence Steam Electric Station 
(Independence Station). Independence Station is located in northeastern 
Arkansas in the eastern portion of Independence County, approximately 5 
kilometers (km) southeast of Newark, Arkansas. Independence Station is 
a large Electrical Generating Unit that was included in the list of 
facilities to be designated pursuant to a March 2, 2015 Consent 
Decree.\2\ There is one other major emitter of SO2 in 
Independence County.\3\ The Future Fuel Corporation facility (Future 
Fuel) located approximately 12 km to the west-northwest of Independence 
Station.
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    \2\ See Sierra Club et al. v. McCarthy, Civil Action No. 3:13-
cv-3953-SI (N.D. Cal.), and 79 FR 31325 (June 2, 2014).
    \3\ Sources over 100 tons per year emissions of SO2 
using EPA's 2014 National Emission Inventory.
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    Independence County was designated unclassifiable on July 12, 
2016.\4\ The unclassifiable designation was based on the information 
the state of Arkansas and the Sierra Club provided to the EPA. 
Specifically, the designation and associated boundaries were based on 
the EPA's evaluation of the State's air dispersion modeling analysis, 
as well as the additional modeling analysis submitted by Sierra Club 
for the area surrounding Independence Station. In summary, the EPA's 
evaluation of the state's modeling supported the need for refined 
emission estimates for the Future Fuel facility to accurately assess 
potential maximum impacts in Independence County. Both ADEQ's and 
Sierra Club's previous modeling provided to the EPA in 2015 and 2016 
were premised on several factors that were not consistent with 
recommendations in the Modeling TAD and were unreliable for determining 
whether the area was or was not meeting the 2010 SO2 NAAQS. 
After careful evaluation of the State's recommendation, all timely 
comments and information received, the EPA concluded that it could not 
determine whether the area around the Independence Station was meeting 
or not meeting the 2010 SO2 primary NAAQS and designated 
that area unclassifiable in July 2016. The boundaries for this 
designation were the jurisdictional boundaries of Independence County, 
based upon the State's recommendation, its submitted analysis and our 
concurrence on the State's reasoning.
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    \4\ 2010 SO2 primary NAAQS Round 2 Designations for 
Arkansas were signed on June 30, 2016, and can be found at 81 FR 
45039, July 12, 2016.
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    Detailed rationale, analyses, and other information supporting our 
original designation for this area can be found in the final action's 
technical support document for Arkansas.\5\ This document, along with 
all other supporting materials for the original 2010 SO2 
primary NAAQS designation for Independence County, can be found at 
www.regulations.gov in Docket ID EPA-HQ-OAR-2014-0464. The technical 
support document for this proposed action is included in the docket for 
this action (Docket EPA-R06-OAR-2018-0624).\6\
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    \5\ Final AR SO2 designation TSD can be found at 
www.regulations.gov; Docket EPA-HQ-OAR-2014-0464-0410).
    \6\ See ``Independence Redesignation TSD.pdf''.
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II. What are the criteria for redesignating an area from unclassifiable 
to attainment/unclassifiable?

    Section 107(d)(3)(A) provides that the Administrator may notify the 
Governor of any state that the designation of an area should be revised 
``on the basis of air quality data, planning and control 
considerations, or any other air quality-related considerations the 
Administrator deems appropriate.'' The Act further provides in section 
107(d)(3)(D) that even if the Administrator has not notified a state 
Governor that a designation should be revised, the Governor of any 
state may, on the Governor's own motion, submit a request to revise the 
designation of any area, and the Administrator must approve or deny the 
request.
    When approving or denying a request to redesignate an area, the EPA 
bases its decision on the air quality data for the area as well as the 
considerations provided under section 107(d)(3)(A).\7\ The EPA defines 
an attainment/unclassifiable area \8\ as: An area for which available 
information does not indicate that the area violates the NAAQS or 
contributes to ambient air quality in a nearby area that does not meet 
the NAAQS or an area for which the EPA has determined the available 
information indicates the area meets the NAAQS and does not indicate 
the area contributes to ambient air quality in a nearby area that does 
not meet the NAAQS. We are proposing to find that Independence County 
would fall under the second definition.
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    \7\ While CAA section 107(d)(3)(E) also lists specific 
requirements for redesignations, those requirements only apply to 
redesignations of nonattainment areas to attainment and, therefore, 
are not applicable in the context of a redesignation of an area from 
unclassifiable to attainment/unclassifiable.
    \8\ Historically, the EPA has designated most areas that do not 
meet the definition of nonattainment as ``unclassifiable/
attainment.'' EPA has reversed the order of the label to be 
``attainment/unclassifiable'' to better convey the definition of the 
designation category and so that the category is more easily 
distinguished from the separate unclassifiable category. See, e.g., 
83 FR 1098, 1099 (January 9, 2018) and 83 FRN 25776, 25778 (June 4, 
2018). EPA reserves the ``attainment'' category for when EPA 
redesignates a nonattainment area that has attained the relevant 
NAAQS and has an approved maintenance plan.
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III. What is EPA's rationale for proposing to redesignate the area?

    Independence County was designated unclassifiable by the EPA on 
July 12, 2016. As discussed previously, modeling results provided by 
Arkansas and Sierra Club in 2015 and 2016 were not refined enough to 
make a clear determination of the area's attainment status. Since that 
designation, the EPA has worked with ADEQ and the two facilities in 
refining the modeling approaches and inputs resulting in modeling that 
is acceptable for assessing whether the area is attaining or not 
attaining the 1-hour SO2 NAAQS. Specifically, ADEQ and the 
facilities have made refinements in the modeling including: Revising 
Future Fuel's emissions estimates to vary emissions based on coal 
usage, using more accurate stack parameters and utilizing a 
meteorological approach which employs the EPA-generated Weather 
Research and Forecasting (WRF) meteorological modeling and the 
Mesoscale Model InterFace (MMIF) program to generate representative 
meteorological data for the Independence County area. The original 
modeling used 2012-2014 meteorological data from the Little Rock area 
which is over 70 miles from Future Fuel and Independence Station, so 
ADEQ wished to use the new 2013-2015 WRF based data to better represent 
the local meteorology in Independence County. EPA worked with ADEQ to 
review the meteorological modeling results within the region and at

[[Page 59352]]

surrounding meteorological stations to assess whether the 
meteorological model was performing adequately. EPA also assessed 
whether the use of the WRF data with 12 km grid resolution was 
acceptable for simulating the meteorological data for Independence 
County. EPA determined model was acceptable to simulate the 
meteorological parameters in Independence County and EPA approved the 
use of the WRF/MMIF meteorological data for use in AERMOD \9\ modeling 
of Independence County.\10\ This approval is included in the docket for 
this action (Docket EPA-R06-OAR-2018-0624). ADEQ submitted an updated 
analysis and letter signed by Governor Asa Hutchinson on April 20, 2018 
requesting that the EPA redesignate Independence County, Arkansas as 
attainment/unclassifiable for the 1-hour SO2 primary NAAQS.
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    \9\ American Meteorological Society (AMS) and U.S. Environmental 
Protection Agency (EPA) Regulatory Model (AERMOD). AERMOD is the 
preferred regulatory model listed in 40 CFR part 51 App. W for 
atmospheric dispersion of primary pollutants within 50 km in this 
terrain situation.
    \10\ Email from Mr. Erik Snyder of EPA Region 6 to Mr. David 
Clark of ADEQ on January 23, 2018 approving the use of surface and 
upper air data from WRF/MMIF for a representative location in 
Independence County, Arkansas.
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    According to the EPA's guidance on redesignations, SO2 
nonattainment areas using modeling to demonstrate attainment for a 
redesignation request would be expected to use maximum allowable 
emissions.\11\ However, these statements derive from the requirements 
of CAA section 107(d)(3)(E), which do not pertain to the redesignation 
of unclassifiable areas. For redesignations of unclassifiable areas, 
the necessary analysis is equivalent to what would be required in a 
designation in the first instance since we have not found the area to 
be attainment or nonattainment. In this first instance, the goal is to 
establish existing ambient air quality. As such, it is appropriate to 
use actual emissions for estimating existing air quality. The EPA's 
acceptance of modeling using actual emissions \12\ in this instance 
should not be construed to define what would be needed for a 
demonstration of attainment and maintenance for purposes of a 
redesignation of a nonattainment area to attainment.
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    \11\ Guidance for 1-Hour SO2 Nonattainment Area SIP 
Submissions, April 2014, at 67; Kent Berry Memorandum ``Use of 
Actual Emissions in Maintenance Demonstrations for ozone and Carbon 
Monoxide (CO) Nonattainment Areas,'' Nov. 30, 1993, at 3.
    \12\ Actual emissions were used for most sources with the 
exception of using allowables for a few minor sources at the Future 
Fuel facility.
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    The EPA has reviewed the modeling provided by the state with their 
redesignation request and finds that it comports with the EPA's, 
current Modeling TAD \13\ and the EPA's Guideline on Air Quality Models 
(40 CFR part 51 Appendix W) and is acceptable for assessing the 
attainment status of Independence County, Arkansas. The state's 
modeling indicates that the predicted maximum Design Value at any 
receptor in the modeling domain is 159.6 [mu]g/m\3\, or 60.92 parts per 
billion (ppb).\14\ The EPA's review confirms the modeling results 
appropriately characterize the air quality in Independence County, 
Arkansas and that predicted ambient SO2 concentrations are 
below the 2010 SO2 primary NAAQS of 196.4 [mu]g/m\3\, or 75 
ppb.
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    \13\ ``Sulfur Dioxide (S02) National Ambient Air 
Quality Standards Designations Modeling Technical Assistance 
Document''. August 2016 draft https://www.epa.gov/sites/production/files/2016-0706/documents/areadesignso2modelingtad.pdf. Note. the 
EPA released earlier drafts of this document in May and 2013 and 
February 2016.
    \14\ The SO2 NAAQS and the Design Value compared to 
the NAAQS is the 3-year average of the annual 99th percentile of 1-
hour daily maximum concentrations.
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IV. Proposed Action

    The EPA is proposing to approve Arkansas' April 20, 2018, request 
to change the EPA's previous designation and redesignate Independence 
County from unclassifiable to attainment/unclassifiable for the 2010 
SO2 primary NAAQS. The EPA has reviewed the modeling 
provided by the state with its redesignation request and finds that it 
comports with the EPA's, current Modeling TAD and the EPA's Guideline 
on Air Quality Models (40 CFR part 51 Appendix W) and is acceptable for 
assessing the attainment status of Independence County, Arkansas. If 
finalized, approval of the redesignation request would change the legal 
designation for the Area, found at 40 CFR part 81, from unclassifiable 
to attainment/unclassifiable for the 2010 SO2 primary NAAQS.

V. Statutory and Executive Order Reviews

    Under the CAA, redesignation of an area to attainment/
unclassifiable is an action that affects the status of a geographical 
area and does not impose any additional regulatory requirements on 
sources beyond those imposed by state law. A redesignation to 
attainment/unclassifiable does not in and of itself create any new 
requirements. Accordingly, this proposed action merely proposes to 
redesignate an area to attainment/unclassifiable and does not impose 
additional requirements. For that reason, this proposed action:
     Is exempt from 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 it is exempt 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 not subject to 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 (Public Law 104-4);
     is not subject because it does not have Federalism 
implications as specified in Executive Order 13132 (64 FR 43255, August 
10, 1999);
     is not subject to Executive Order 13045 (62 FR 19885, 
April 23, 1997) because it does not establish an environmental standard 
intended to mitigate health or safety risks;
     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 this action does not involve technical standards;
     will not have disproportionate human health or 
environmental effects under Executive Order 12898 (59 FR 7629, February 
16, 1994); and
     does not have Tribal implications as specified by 
Executive Order 13175 (65 FR 67249, November 9, 2000) because no tribal 
lands are located within the Area and the redesignation does not create 
new requirements. The EPA notes this proposed action will not impose 
substantial direct costs on Tribal governments or preempt Tribal law.

List of Subjects in 40 CFR Part 81

    Environmental protection, Air pollution control, National parks, 
Wilderness areas.

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

    Dated: November 16, 2018.
Anne Idsal,
Regional Administrator, Region 6.
[FR Doc. 2018-25477 Filed 11-21-18; 8:45 am]
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