[Federal Register Volume 85, Number 163 (Friday, August 21, 2020)]
[Notices]
[Pages 51694-51698]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-18129]
-----------------------------------------------------------------------
ENVIRONMENTAL PROTECTION AGENCY
[EPA-HQ-OAR-2020-0037; FRL-10013-82-OAR]
EPA Responses to Certain State Designation Recommendations for
the 2010 Sulfur Dioxide Primary National Ambient Air Quality Standard:
Notice of Availability and Public Comment Period
AGENCY: Environmental Protection Agency (EPA).
ACTION: Notice of availability and public comment period.
-----------------------------------------------------------------------
SUMMARY: Notice is hereby given that the Environmental Protection
Agency (EPA) has posted our responses to certain state designation
recommendations for the 2010 Sulfur Dioxide (SO2) Primary
National Ambient Air Quality Standard (NAAQS) on the Agency's website
and electronic docket. These responses include our intended
designations for the affected areas, specifically all remaining
undesignated areas for the 2010 SO2 NAAQS in the United
States. The EPA also invites the public to review and provide input on
our intended designations during the comment period specified in the
DATES section. The EPA sent its responses directly to the states on or
about August 13, 2020. The EPA intends to make final designation
determinations for the areas of the country addressed by these
responses no later than December 31, 2020.
DATES: Comments must be received on or before September 21, 2020.
Please refer to SUPPLEMENTARY INFORMATION for additional information on
the comment period.
ADDRESSES: Submit your comments, identified by Docket ID No. EPA-HQ-
OAR-2020-0037, at https://www.regulations.gov.\1\ Follow the online
instructions for submitting comments. Out of an abundance of caution
for members of the public and our staff, the EPA Docket Center and
Reading Room are closed to the public, with limited exceptions, to
reduce the risk of transmitting COVID-19. Our Docket Center staff will
continue to provide remote customer service via email, phone, and
webform. We encourage the public to submit comments via https://www.regulations.gov, as there may be a delay in processing mail and
faxes. Hand deliveries and couriers may be received by scheduled
appointment only. For further information on EPA Docket Center services
and the current status, please visit us online at https://www.epa.gov/dockets.
---------------------------------------------------------------------------
\1\ The https://www.regulations.gov platform is in the process
of being upgraded. Users may be automatically redirected to https://beta.regulations.gov. Both website addresses contain the same
information and both website addresses allow users to submit
comments to the docket.
---------------------------------------------------------------------------
Once submitted, comments cannot be edited or removed from
regulations.gov. The EPA may publish any comment received to our 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., comments hosted 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: For general questions concerning this
action, please contact Corey Mocka, U.S. Environmental Protection
Agency, Office of Air Quality Planning and Standards, Air Quality
Policy Division, 109 T.W. Alexander Drive, Mail Code C539-04, Research
Triangle Park, NC 27711; telephone: (919) 541-5142; email address:
[email protected]. The following EPA contacts can answer questions
regarding areas in a particular EPA Regional office:
U.S. EPA Regional Office Contacts
Region 2--Marina Castro, telephone (212) 637-3713, email at
[email protected].
Region 3--Megan Goold, telephone (215) 814-2027, email at
[email protected].
Region 4--Twunjala Bradley, telephone (404) 562-9352, email at
[email protected].
Region 5--Alisa Liu, telephone (312) 353-3193, email at
[email protected].
Region 6--Robert Imhoff, telephone (214) 665-7262, email at
[email protected].
Region 7--William Stone, telephone (913) 551-7714, email at
[email protected].
Region 8--Rebecca Matichuk, telephone (303) 312-6867, email at
[email protected].
Region 9--Ashley R. Graham, telephone (415) 972-3877, email at
[email protected].
Region 10--John Chi, telephone (206) 553-1185, email at
[email protected].
------------------------------------------------------------------------
Regional offices Affected state(s)
------------------------------------------------------------------------
EPA Region 2--Air Programs Branch, 290 New York.
Broadway, 25th Floor, New York, NY 10007.
EPA Region 3--Planning & Implementation Maryland, Pennsylvania,
Branch, 1650 Arch Street, Philadelphia, PA Virginia, and West
19103. Virginia.
EPA Region 4--Air Planning & Implementation Alabama, Georgia, Kentucky,
Branch, Sam Nunn Atlanta Federal Center, and North Carolina.
61 Forsyth Street SW, 12th Floor, Atlanta,
GA 30303.
EPA Region 5--Air Programs Branch, Air & Illinois, Indiana, and
Radiation Division (AR-18J), 77 West Wisconsin.
Jackson Blvd., Chicago, IL 60604.
EPA Region 6--State Planning & Louisiana, Oklahoma, and
Implementation Branch, 1201 Elm Street, Texas.
Dallas, TX 75270.
EPA Region 7--Air Quality Planning Branch, Missouri and Nebraska.
11201 Renner Blvd., Lenexa, KS 66219.
EPA Region 8--Air Quality Planning Branch, North Dakota and Wyoming.
1595 Wynkoop Street, Denver, CO 80202.
EPA Region 9--Air Planning Branch, 75 Hawaii.
Hawthorne Street, San Francisco, CA 94105.
EPA Region 10--Air Planning & State/Tribal Washington.
Coordinations Branch, 1200 Sixth Avenue,
Mail Code OAQ-107, Seattle, WA 98101.
------------------------------------------------------------------------
[[Page 51695]]
Most EPA offices are closed to reduce the risk of transmitting
COVID-19, but staff remain available via telephone and email. The EPA
encourages the public to review designation recommendations from
states, our recent letters notifying the affected states of our
intended designations, and area-specific technical support information
online at https://www.epa.gov/sulfur-dioxide-designations and also in
the public docket for these SO2 designations at https://www.regulations.gov under Docket ID No. EPA-HQ-OAR-2020-0037.
SUPPLEMENTARY INFORMATION:
Table of Contents
The following is an outline of the Preamble.
I. What is the purpose of this action?
II. Instructions for Submitting Public Comments and internet website
for Rulemaking Information
III. What is the 2010 SO2 NAAQS and what are the health
concerns that it addresses?
IV. What are the CAA requirements for air quality designations and
what action has the EPA taken to meet these requirements?
V. What guidance has the EPA previously issued and how does the EPA
now intend to apply the statutory requirements to determine area
designations and boundaries?
VI. What air quality information has the EPA used for these intended
designations?
VII. How do the Round 4 designations affect Indian country?
VIII. Where can I find information forming the basis for these
intended designations and exchanges between the EPA and states
related to these intended designations?
I. What is the purpose of this action?
The purpose of this notice of availability is to solicit input from
interested parties on the EPA's recent responses to the state
designation recommendations for the 2010 SO2 NAAQS. These
responses, and their supporting technical analyses, can be found at
https://www.epa.gov/sulfur-dioxide-designations and also in the public
docket for these SO2 designations at https://www.regulations.gov under Docket ID No. EPA-HQ-OAR-2020-0037.
On June 2, 2010, the EPA Administrator signed a final rule that
revised the primary SO2 NAAQS (75 FR 35520; June 22, 2010)
after review of the existing primary SO2 standards
promulgated on April 30, 1971 (36 FR 8187). The EPA established the
revised primary SO2 NAAQS at a level of 75 parts per billion
(ppb) which is attained when the 3-year average of annual 99th
percentile of daily maximum 1-hour average concentrations of
SO2 does not exceed 75 ppb.
The process for designating areas following promulgation of a new
or revised NAAQS is contained in the Clean Air Act (CAA or Act) section
107(d) (42 U.S.C. 7407(d)). After promulgation of a new or revised
NAAQS, each governor or tribal leader has an opportunity to recommend
air quality designations, including the appropriate boundaries for
nonattainment areas, to the EPA. The EPA considers these
recommendations as part of its duty to promulgate the formal area
designations and boundaries for the new or revised NAAQS. By no later
than 120 days prior to promulgating designations, the EPA is required
to notify states, territories, and tribes, as appropriate, of any
intended modifications to an area designation or boundary
recommendation that the EPA deems necessary.
After invoking a 1-year extension of the deadlines to designate
areas, as provided for in section 107 of the Act, the EPA completed an
initial round of SO2 designations for certain areas of the
country on July 25, 2013 (referred to as ``Round 1'').\2\ Following the
initial designations, three lawsuits were filed against the EPA in
different U.S. District Courts, alleging the agency had failed to
perform a nondiscretionary duty under the CAA by not designating all
portions of the country by the June 2, 2013, deadline. In one of those
cases, the U.S. District Court for the Northern District of California
on March 2, 2015, entered an enforceable order for the EPA to complete
the area designations by three specific deadlines according to the
court-ordered schedule.\3\
---------------------------------------------------------------------------
\2\ A total of 29 areas throughout the U.S. were designated in
this action published on August 5, 2013 (78 FR 47191). The EPA
designated all 29 areas nonattainment based on violating monitored
SO2 concentrations from Federal Reference Method and
Federal Equivalent Method monitors that are sited and operated in
accordance with 40 CFR parts 50 and 58, and did not at that time
designate any other areas.
\3\ Sierra Club v. McCarthy, No. 3-13-cv-3953 (SI) (N.D. Cal.
Mar. 2, 2015).
---------------------------------------------------------------------------
To meet the first court-ordered deadline, additional areas were
designated on June 30, 2016, and November 29, 2016 (collectively
referred to as ``Round 2'').\4\ To meet the second deadline of the
court-ordered schedule, the EPA completed SO2 designations
for most remaining areas of the country on December 21, 2017, and March
28, 2018 (collectively referred to as ``Round 3'').\5\ Finally, the EPA
is under a December 31, 2020, court-ordered deadline, the final of the
three deadlines established by the court, to designate all remaining
undesignated areas (collectively referred to as ``Round 4'' or the
``final round''). The remaining undesignated areas are: (1) Those areas
which, under the court order, did not meet the criteria that required
designation in Round 2 and also were not required to be designated in
Round 3 due to installation and operation of a new SO2
monitoring network by January 2017 in the area meeting EPA's
specifications referenced in EPA's SO2 Data Requirements
Rule (DRR),\6\ and (2) those areas which EPA has not otherwise
previously designated for the 2010 SO2 NAAQS. After these
Round 4 designations are completed, there will be no remaining
undesignated areas for the 2010 SO2 NAAQS.
---------------------------------------------------------------------------
\4\ A total of 65 areas throughout the U.S. were designated in
these actions published on July 12, 2016 (81 FR 45039), and December
13, 2016 (81 FR 89870). Of these 65 areas, seven were designated
nonattainment.
\5\ Most remaining areas of the U.S. were designated in actions
published on January 9, 2018 (83 FR 1098) and April 5, 2018 (83 FR
14597). Of these areas, six were designated nonattainment.
\6\ See 80 FR 51052 (August 21, 2015), codified at 40 CFR part
51 subpart BB.
---------------------------------------------------------------------------
On or about August 13, 2020, consistent with section
107(d)(1)(b)(ii) of the CAA, the EPA notified affected states either of
our assessment of their recommended designations for Round 4 or of our
intended designations for areas without recommendations. While we are
in agreement with the recommendations for many areas, some may warrant
further discussion. The EPA is available to assist and hopes to resolve
any differences regarding the proper designation for these areas within
the 120-day period provided by the CAA.
For any areas that we designate nonattainment in our final action,
the CAA directs states to develop and submit to the EPA State
Implementation Plans within 18 months of the effective date of the
final designations, that meet the requirements of CAA sections 172(c)
and 191-192 and provide for attainment of the NAAQS as expeditiously as
practicable, but not later than 5 years from the effective date of the
final designations.
II. Instructions for Submitting Public Comments and Internet Website
for Rulemaking Information
A. Invitation To Comment
The purpose of this document is to solicit input from interested
parties, other than the states to which we have sent notification
letters, on the EPA's recent responses to the designation
recommendations for the 2010 SO2 NAAQS. These responses, and
their
[[Page 51696]]
supporting technical analyses, can be found at https://www.epa.gov/sulfur-dioxide-designations and also in the public docket for these
intended SO2 designations at https://www.regulations.gov
under Docket ID No. EPA-HQ-OAR-2020-0037.
CAA section 107(d) provides a process for air quality designations
that involves recommendations by states, territories, and tribes to the
EPA and responses from the EPA to those parties, prior to the EPA
promulgating final area designations and boundaries. The EPA is not
required under CAA section 107(d) to seek public comment during the
designation process, but we are electing to do so for these areas with
respect to the 2010 SO2 NAAQS in order to gather additional
information for the EPA to consider before making final designations
for the specific areas addressed in the EPA's recent letters to states,
territories, and tribes. The EPA invites public input on our responses
to states regarding our intended designations for these areas during
the 30-day comment period provided in this document. In order to
receive full consideration, input from the public must be submitted to
the docket by September 21, 2020. At this time, the EPA is not asking
for public comments on areas beyond those areas that are the subject of
this proposed action. This document and opportunity for public comment
does not affect any rights or obligations of any state, territory, or
tribe, or of the EPA, which might otherwise exist pursuant to the CAA
section 107(d).
Please refer to the FOR FURTHER INFORMATION CONTACT section of this
document for specific instructions on submitting comments and locating
relevant public documents.
For some cases, the EPA has indicated to a state that further
discussion is needed--e.g., where a state's recommended nonattainment
area boundary differs from the EPA's intended nonattainment area
boundary, or areas where the state recommended a designation of
attainment/unclassifiable (or unclassifiable) and available air quality
monitoring or modeling data show that the area may be violating the
2010 SO2 NAAQS or contain sources that may be contributing
to air quality in a nearby area that may be violating the 2010 primary
SO2 NAAQS. In establishing nonattainment area boundaries for
a particular area, the EPA is required to include within the boundaries
both the area that does not meet the standard and any nearby area
contributing to the area that does not meet the standard. We are
particularly interested in receiving comments, supported by relevant
information, if you believe that a specific geographic area for which
further discussion is needed concerning a state's recommended
designation of attainment/unclassifiable or unclassifiable (and for
which available air quality data would require a modification of the
recommended designation) should not be categorized by the CAA section
107(d) criteria as nonattainment, or if you believe that a specific
nearby area for which the EPA does agree with a state's recommended
designation of attainment/unclassifiable or unclassifiable should in
fact be categorized as contributing to nonattainment using the CAA
section 107(d) criteria. Please be as specific as possible in
supporting your views.
Describe any assumptions and provide any technical
information and/or data that you used.
Provide specific examples to illustrate your concerns and
suggest alternatives.
Explain your views as clearly as possible.
Provide your input by the comment period deadline
identified.
The EPA intends to complete designations for the areas subject to
this round no later than December 31, 2020. Additional information on
the EPA's intended approach for addressing designations for all areas
can be found on the EPA's SO2 implementation website at
https://www.epa.gov/so2-pollution/applying-or-implementing-sulfur-dioxide-standards.
B. What should I consider as I prepare my comments for the EPA?
1. Submitting CBI. Do not submit confidential business information
(CBI) to the EPA through https://www.regulations.gov or email. Clearly
mark the part or all of the information that you claim to be CBI. For
CBI in a USB flash drive or CD ROM that you mail to the EPA, mark the
outside of the USB flash drive or CD ROM as CBI and then identify
electronically within the USB flash drive or CD ROM the specific
information that is claimed as CBI. In addition to one complete version
of the comment that includes information claimed as CBI, a copy of the
comment that does not contain the information claimed as CBI must be
submitted for inclusion in the public docket. Information so marked
will not be disclosed except in accordance with procedures set forth in
40 Code of Federal Regulations (CFR) part 2.
Send information identified as CBI only to the following address:
Tiffany Purifoy, OAQPS Document Control Officer, U.S. EPA, Office of
Air Quality Planning and Standards, 109 T.W. Alexander Drive, Mail Code
C404-02, Research Triangle Park, NC 27711, Attention Docket ID No. EPA-
HQ-OAR-2020-0037. There will be a delay in confirming receipt of CBI
packages, because the EPA-RTP office is closed to reduce the risk of
transmitting COVID-19. Due to the office closure, EPA is also
requesting that parties notify the OAQPS Document Control Officer via
telephone, (919) 541-0878, or email at [email protected] when
mailing information identified as CBI.
2. Tips for Preparing Your Comments. When submitting comments,
remember to:
Identify the rulemaking by docket number and other
identifying information (subject heading, Federal Register date and
page number).
Follow directions.
Explain why you agree or disagree; suggest alternatives
and substitute language for your requested changes.
C. Where can I find additional information for this rulemaking?
The EPA has also established a website for this rulemaking at
https://www.epa.gov/sulfur-dioxide-designations. The website includes
the state designation and boundary recommendations, the EPA's intended
area designations, information supporting the EPA's preliminary
designation decisions, as well as the rulemaking actions and other
related information that the public may find useful.
III. What is the 2010 SO2 NAAQS and what are the health
concerns that it addresses?
The Administrator signed a final rule revising the primary
SO2 NAAQS on June 2, 2010. The rule was published in the
Federal Register on June 22, 2010 (75 FR 35520) and became effective on
August 23, 2010. Specifically, the EPA established a new 1-hour
SO2 standard at a level of 75 ppb, which is met at an
ambient air quality monitoring site when the 3-year average of the
annual 99th percentile of daily maximum 1-hour average concentrations
of SO2 is less than or equal to 75 ppb, as determined in
accordance with appendix T of 40 CFR part 50. 40 CFR 50.17(a) and (b).
Current scientific evidence links short-term exposures to
SO2, ranging from 5 minutes to 24 hours, with an array of
adverse respiratory effects including bronchoconstriction and increased
asthma symptoms. Studies also show a connection between short-term
exposure and increased visits to emergency departments and hospital
admissions for respiratory illnesses,
[[Page 51697]]
particularly in at-risk populations including children, the elderly,
and asthmatics.\7\
---------------------------------------------------------------------------
\7\ See 75 FR 35520 at 35525, June 22, 2010.
---------------------------------------------------------------------------
IV. What are the CAA requirements for air quality designations and what
action has the EPA taken to meet these requirements?
After the EPA promulgates a new or revised NAAQS, the EPA is
required to designate all areas of the country as either
``nonattainment,'' ``attainment,'' or ``unclassifiable,'' for that
NAAQS pursuant to section 107(d)(1)-(2) of the CAA. As part of these
Round 4 designations, the EPA is implementing its interpretation of
statutory terms under CAA section 107(d) nationwide and is basing these
designations on EPA's nationwide analytical approach and technical
analysis, including evaluation of monitoring data and air quality
modeling, applied to the available evidence for each area.
Regarding statutory definitions and the EPA's interpretations of
such, section 107(d)(1)(A)(i) of the CAA defines a nonattainment area
as an area that does not meet the NAAQS or that contributes to a nearby
area that does not meet the NAAQS. An attainment area is defined by
section 107(d)(1)(A)(ii) of the CAA as any area (other than an area
that meets the definition of a nonattainment area) that meets the
NAAQS. Unclassifiable areas are defined by section 107(d)(1)(A)(iii) of
the CAA as those that cannot be classified on the basis of available
information as meeting or not meeting the NAAQS.
In this action, the EPA defines a nonattainment area as an area
that, based on available information including (but not limited to)
monitoring data and/or appropriate modeling analyses, the EPA has
determined either: (1) Does not meet the 2010 SO2 NAAQS, or
(2) contributes to ambient air quality in a nearby area that does not
meet the NAAQS. An attainment/unclassifiable area is defined as an area
that, based on available information including (but not limited to)
appropriate monitoring data and/or modeling analyses, the EPA has
determined meets the NAAQS and does not likely contribute to ambient
air quality in a nearby area that does not meet the NAAQS. An
unclassifiable area is defined as an area for which the available
information does not allow the EPA to determine whether the area meets
the definition of a nonattainment area or the definition of an
attainment/unclassifiable area.
This nationwide analytical approach also includes but is not
limited to: (1) The EPA's interpretations of other terms (e.g.,
attainment/unclassifiable, nonattainment, unclassifiable, violating
monitor, etc.) in the context of Round 4 of the 2010 SO2
NAAQS; (2) the appropriate basis for characterizing the air quality of
an area; (3) the five-factor analysis to determine the boundaries for
each air quality area under the NAAQS (see Section V of this document);
and (4) the methodology for appropriately characterizing SO2
air quality through monitoring or modeling.
The EPA notes that CAA section 107(d) provides the agency with
discretion to determine how best to interpret the terms in the
definition of a nonattainment area (e.g., ``contributes to'' and
``nearby'') for a new or revised NAAQS, given considerations such as
the nature of a specific pollutant, the types of sources that may
contribute to violations, the form of the standards for the pollutant,
and other relevant information. In particular, the EPA's position is
that the statute does not require the agency to establish bright line
tests or thresholds for what constitutes ``contribution'' or ``nearby''
for purposes of designations.\8\
---------------------------------------------------------------------------
\8\ This view was confirmed in Catawba County v. EPA, 571 F.3d
20 (D.C. Cir. 2009).
---------------------------------------------------------------------------
Similarly, the EPA's position is that the statute permits the EPA
to evaluate the appropriate application of the term ``area'' to include
geographic areas based upon full or partial county boundaries, as may
be appropriate for a particular NAAQS. For example, CAA section
107(d)(1)(B)(ii) explicitly provides that the EPA can make
modifications to designation recommendations for an area ``or portions
thereof,'' and under CAA section 107(d)(1)(B)(iv) a designation remains
in effect for an area ``or portion thereof'' until the EPA redesignates
it.
By no later than 1 year after the promulgation of a new or revised
NAAQS, CAA section 107(d)(1)(A) provides that each state governor is
required to recommend air quality designations, including the
appropriate boundaries for areas, to the EPA.\9\ The EPA reviews those
recommendations and is authorized to make any modifications the
Administrator deems necessary. The statute does not define the term
``necessary,'' but the EPA interprets this to authorize the
Administrator to modify designations that did not meet the statutory
requirements or were otherwise inconsistent with the facts or analysis
deemed appropriate by the Administrator. If the EPA is considering
modifications to a recommendation, we are required by CAA section
107(d)(1)(B)(ii) to notify the state of any such intended modifications
not less than 120 days prior to our promulgation of the final
designation. These notifications are commonly known as the ``120-day
letters.'' During this period, if the state or territory does not agree
with the EPA's modification, it has an opportunity to respond to the
EPA and to demonstrate why it believes the modification proposed by the
EPA is inappropriate. If a state or territory fails to provide any
recommendation for an area, in whole or in part, the EPA still must
promulgate a designation that the Administrator deems appropriate,
pursuant to CAA section 107(d)(1)(B)(ii). While CAA section 107(d)
specifically addresses the designations process between the EPA and
states and territories, the EPA intends to follow the same process to
the extent practicable for tribes that submitted designation
recommendations. The EPA is required by CAA section 107(d)(2)(A) to
publish a notice in the Federal Register promulgating its final
designations, and the EPA codifies its designations in the Code of
Federal Regulations at 40 CFR part 81, subpart C.
---------------------------------------------------------------------------
\9\ Tribes are invited to submit recommendations following
promulgation of a new or revised NAAQS but are not required to do
so.
---------------------------------------------------------------------------
V. What guidance has the EPA previously issued and how does the EPA now
intend to apply the statutory requirements to determine area
designations and boundaries?
In the notice of proposed rulemaking for the revised SO2
NAAQS (74 FR 64810; December 8, 2009), the EPA issued proposed guidance
on our approach to implementing the standard, including our approach to
initial area designations. The EPA solicited comment on that guidance
and, in the final rule (75 FR 35520; June 22, 2010), provided further
guidance concerning implementation of the standard and how to identify
nonattainment areas and boundaries for the SO2 NAAQS.
Subsequently, on March 24, 2011, the EPA provided additional
designations guidance to assist states with making their
recommendations for area designations and boundaries.\10\ The EPA also
issued two additional designations guidance documents on March 20,
2015,
[[Page 51698]]
and July 22, 2016, specific to Round 2 and Round 3 processes and
schedules, respectively.\11\
---------------------------------------------------------------------------
\10\ See ``Area Designations for the 2010 Revised Primary Sulfur
Dioxide National Ambient Air Quality Standards,'' memorandum to
Regional Air Division Directors, Regions I-X, from Stephen D. Page,
dated March 24, 2011, available at https://www3.epa.gov/ttn/naaqs/aqmguide/collection/cp2/20110324_page_so2_designations_guidance.pdf.
\11\ See ``Updated Guidance for Area Designations for the 2010
Primary Sulfur Dioxide National Ambient Air Quality Standard,''
memorandum to Regional Air Division Directors, Regions 1-10, from
Stephen D. Page, dated March 20, 2015, available at https://www.epa.gov/sites/production/files/2016-04/documents/20150320so2designations.pdf, and ``Area Designations for the 2010
Primary Sulfur Dioxide National Ambient Air Quality Standard--Round
3,'' memorandum to Regional Air Division Directors, Regions 1-10,
dated July 22, 2016, available at https://www.epa.gov/sites/production/files/2016-07/documents/areadesign.pdf.
---------------------------------------------------------------------------
An updated designations guidance document was issued by the EPA on
September 5, 2019, to better reflect the Round 4 2010 SO2
NAAQS designations process and to supplement, where necessary, prior
designations guidance documents.\12\ This memorandum identifies factors
that the EPA intends to evaluate in determining whether areas are in
violation of the 2010 SO2 NAAQS. The document also contains
the factors that the EPA intends to evaluate in determining the
boundaries for all remaining undesignated areas in the country. These
factors include: (1) Air quality characterization via ambient
monitoring and/or dispersion modeling results; (2) emissions-related
data; (3) meteorology; (4) geography and topography; and (5)
jurisdictional boundaries.\13\
---------------------------------------------------------------------------
\12\ See ``Area Designations for the 2010 Primary Sulfur Dioxide
National Ambient Air Quality Standard--Round 4,'' memorandum to
Regional Air Division Directors, Regions 1-10, from Peter
Tsirigotis, dated September 5, 2019, available at https://www.epa.gov/sites/production/files/2019-09/documents/round_4_so2_designations_memo_09-05-2019_final.pdf.
\13\ The EPA supplemented this guidance with documents first
made available to states and other interested parties in 2013 and
updated in 2016. See SO2 NAAQS Designations Source-
Oriented Monitoring Technical Assistance Document (February 2016),
available at https://www.epa.gov/sites/production/files/2016-06/documents/so2monitoringtad.pdf, and SO2 NAAQS
Designations Modeling Technical Assistance Document (August 2016),
available at https://www.epa.gov/sites/production/files/2016-06/documents/so2modelingtad.pdf.
---------------------------------------------------------------------------
VI. What air quality information has the EPA used for these intended
designations?
These intended designations are based on the EPA's application of
the nationwide analytical approach to, and preliminary 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. With respect to air quality monitoring data, the EPA
has considered data from at least the most recent 3 full calendar
years, i.e., 2017-2019. The 1-hour primary SO2 standard is
violated at an ambient air quality monitoring site when the 3-year
average of the annual 99th percentile of the daily maximum 1-hour
average concentrations of SO2 exceeds 75 ppb, as determined
in accordance with Appendix T of 40 CFR part 50.
In the EPA's September 2019 memorandum, we noted that Round 4 area
designations will be based primarily on ambient monitoring data,
including data from existing and new EPA-approved monitors that have
collected data at least from January 2017 forward, pursuant to the DRR.
In addition, EPA may evaluate air dispersion modeling submitted by
state air agencies for two specific circumstances. First, states may
submit air dispersion modeling of actual or allowable emissions to
support the geographic extent of a nonattainment boundary. Second,
states may submit air dispersion modeling of allowable emissions to
demonstrate that new permanent and federally enforceable SO2
emissions limits that subject sources are meeting provide for
attainment of the NAAQS and represent a more accurate characterization
of current air quality at the time of designation than does monitoring
data reflecting past air quality that does not account for compliance
with new limits and associated enforceable emissions reductions.
VII. How do the Round 4 designations affect Indian country?
There are no violating monitors for areas of Indian county, so no
areas of Indian country are being designated as nonattainment as part
of this round. Any other parts of Indian country being designated as
attainment/unclassifiable or unclassifiable are being designated along
with the surrounding state area.
VIII. Where can I find information forming the basis for these intended
designations and exchanges between the EPA and states related to these
intended designations?
Information providing the basis for this intended action are
provided in a technical support document (TSD) \14\ included in the
docket. The TSD, technical assistance documents, applicable EPA
guidance memoranda, and copies of correspondence regarding this process
between the EPA and the states, territories, tribes, and other parties,
are available for review at the public docket for these SO2
designations at https://www.regulations.gov under Docket ID No. EPA-HQ-
OAR-2020-0037, at the EPA Docket Center listed in the FOR FURTHER
INFORMATION CONTACT section of this document, and on the Agency's
SO2 Designations website at https://www.epa.gov/sulfur-dioxide-designations. Air dispersion modeling input and output files
are too large to post in the docket or on the website and must be
requested from the EPA Docket Office or the Regional office contacts
listed in the FOR FURTHER INFORMATION CONTACT section of this document.
---------------------------------------------------------------------------
\14\ The single TSD for this action consists of a few sections
with information that applies to all affected areas or to certain
groups of areas with some common features, and many sections that
are specific to individual states. For convenience, the term ``TSD''
is also used generically to refer to these state-specific sections.
For informational purposes, these individual state-specific TSDs are
available for separate downloading from the indicated EPA website.
Dated: August 13, 2020.
Panagiotis Tsirigotis,
Director, Office of Air Quality Planning & Standards.
[FR Doc. 2020-18129 Filed 8-20-20; 8:45 am]
BILLING CODE 6560-50-P