Proposed Rule2021-20349
Air Plan Approval; TN; Montgomery County Limited Maintenance Plan for the 1997 8-Hour Ozone NAAQS
Primary source
Metadata and text below are from the Federal Register, a public-domain U.S. government work. Always verify the official published version before relying on it for any legal matter.
Published
September 23, 2021
Issuing agencies
Environmental Protection Agency
Abstract
The Environmental Protection Agency (EPA) is proposing to approve a state implementation plan (SIP) revision submitted by the State of Tennessee, through the Tennessee Department of Environment and Conservation (TDEC), Air Pollution Control Division, on June 23, 2020. The SIP revision includes the 1997 8-hour ozone national ambient air quality standards (NAAQS) Limited Maintenance Plan (LMP) for the Montgomery County, Tennessee portion of the Clarksville-Hopkinsville Area (hereinafter referred to as the "Montgomery County Area" or "Area"). The Clarksville-Hopkinsville Area is comprised of Montgomery County, Tennessee, and Christian County, Kentucky. EPA is proposing to approve Tennessee's LMP for the Montgomery County Area because it provides for the maintenance of the 1997 8-hour ozone NAAQS within the Montgomery County Area through the end of the second 10-year portion of the maintenance period. The effect of this action would be to make certain commitments related to maintenance of the 1997 8-hour ozone NAAQS in the Montgomery County Area federally enforceable as part of the Tennessee SIP.
Full Text
<html>
<head>
<title>Federal Register, Volume 86 Issue 182 (Thursday, September 23, 2021)</title>
</head>
<body><pre>
[Federal Register Volume 86, Number 182 (Thursday, September 23, 2021)]
[Proposed Rules]
[Pages 52864-52870]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2021-20349]
=======================================================================
-----------------------------------------------------------------------
ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 52
[EPA-R04-OAR-2020-0428; FRL-8911-01-R4]
Air Plan Approval; TN; Montgomery County Limited Maintenance Plan
for the 1997 8-Hour Ozone NAAQS
AGENCY: Environmental Protection Agency (EPA).
ACTION: Proposed rule.
-----------------------------------------------------------------------
SUMMARY: The Environmental Protection Agency (EPA) is proposing to
approve a state implementation plan (SIP) revision submitted by the
State of Tennessee, through the Tennessee Department of Environment and
Conservation (TDEC), Air Pollution Control Division, on June 23, 2020.
The SIP revision includes the 1997 8-hour ozone national ambient air
quality standards (NAAQS) Limited Maintenance Plan (LMP) for the
Montgomery County, Tennessee portion of the Clarksville-Hopkinsville
Area (hereinafter referred to as the ``Montgomery County Area'' or
``Area''). The Clarksville-Hopkinsville Area is comprised of Montgomery
County, Tennessee, and Christian County, Kentucky. EPA is proposing to
approve Tennessee's LMP for the Montgomery County Area because it
provides for the maintenance of the 1997 8-hour ozone NAAQS within the
Montgomery County Area through the end of the second 10-year portion of
the maintenance period. The effect of this action would be to make
certain commitments related to maintenance of the 1997 8-hour ozone
NAAQS in the Montgomery County Area federally enforceable as part of
the Tennessee SIP.
DATES: Comments must be received on or before October 25, 2021.
ADDRESSES: Submit your comments, identified by Docket ID No. EPA-R04-
OAR-2020-0428 at <a href="http://www.regulations.gov">http://www.regulations.gov</a>. Follow the online
instructions for submitting comments. Once submitted, comments cannot
be edited or removed from <a href="http://Regulations.gov">Regulations.gov</a>. 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. 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 <a href="http://www2.epa.gov/dockets/commenting-epa-dockets">http://www2.epa.gov/dockets/commenting-epa-dockets</a>.
FOR FURTHER INFORMATION CONTACT: Sarah LaRocca, Air Regulatory
Management Section, Air Planning and Implementation Branch, Air and
Radiation Division, U.S. Environmental Protection Agency, Region 4, 61
Forsyth Street SW, Atlanta, Georgia 30303-8960. The telephone number is
(404) 562-8994. Ms. LaRocca can also be reached via electronic mail at
<a href="/cdn-cgi/l/email-protection#056964776a6666642b766477646d456075642b626a73"><span class="__cf_email__" data-cfemail="f995988b969a9a98d78a988b9891b99c8998d79e968f">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION:
Table of Contents
I. Summary of EPA's Proposed Action
II. Background
III. Tennessee's SIP Submittal
IV. EPA's Evaluation of Tennessee's SIP Submittal
A. Attainment Emissions Inventory
B. Maintenance Demonstration
C. Monitoring Network and Verification of Continued Attainment
D. Contingency Plan
E. Conclusion
V. Transportation Conformity
VI. Proposed Action
VII. Statutory and Executive Order Reviews
I. Summary of EPA's Proposed Action
In accordance with the Clean Air Act (CAA or Act), EPA is proposing
to approve the Montgomery County Area LMP for the 1997 8-hour ozone
NAAQS, adopted by TDEC on June 10, 2020, and submitted by TDEC as a
revision to the Tennessee SIP on June 23, 2020. In 2004, the Montgomery
County Area was designated as nonattainment for the 1997 8-hour ozone
NAAQS. Subsequently, in 2005, after having clean data and EPA's
approval of a maintenance plan, the Area was redesignated to attainment
for the 1997 8-hour ozone NAAQS. See 70 FR 55559 (September 22, 2005).
The Montgomery County Area LMP, submitted by TDEC on June 23, 2020,
is designed to maintain the 1997 8-hour ozone NAAQS within the
Montgomery County Area through the end of the second 10-year portion of
the maintenance period beyond redesignation. EPA is proposing to
approve the plan because it meets all applicable requirements under CAA
sections 110 and 175A.
As a general matter, the Montgomery County Area LMP relies on the
same
[[Page 52865]]
control measures and contingency provisions to maintain the 1997 8-hour
ozone NAAQS during the second 10-year portion of the maintenance period
as the maintenance plan submitted by TDEC for the first 10-year period.
II. Background
Ground-level ozone is formed when oxides of nitrogen
(NO<INF>X</INF>) and volatile organic compounds (VOC) react in the
presence of sunlight. These two pollutants, referred to as ozone
precursors, are emitted by many types of pollution sources, including
on- and off-road motor vehicles and engines, power plants and
industrial facilities, and smaller area sources such as lawn and garden
equipment and paints. Scientific evidence indicates that adverse public
health effects occur following exposure to ozone, particularly in
children and in adults with lung disease. Breathing air containing
ozone can reduce lung function and inflame airways, which can increase
respiratory symptoms and aggravate asthma and other lung diseases.
Ozone exposure also has been associated with increased
susceptibility to respiratory infections, medication use, doctor
visits, and emergency department visits and hospital admissions for
individuals with lung disease. Children are at increased risk from
exposure to ozone because their lungs are still developing and they are
more likely to be active outdoors, which increases their exposure.\1\
---------------------------------------------------------------------------
\1\ See ``Fact Sheet, Proposal to Revise the National Ambient
Air Quality Standards for Ozone,'' January 6, 2010 and 27 FR 2938
(January 19, 2010).
---------------------------------------------------------------------------
In 1979, under section 109 of the CAA, EPA established primary and
secondary NAAQS for ozone at 0.12 parts per million (ppm), averaged
over a 1-hour period. See 44 FR 8202 (February 8, 1979). On July 18,
1997, EPA revised the primary and secondary NAAQS for ozone to set the
acceptable level of ozone in the ambient air at 0.08 ppm, averaged over
an 8-hour period. See 62 FR 38856 (July 18, 1997).\2\ EPA set the 8-
hour ozone NAAQS based on scientific evidence demonstrating that ozone
causes adverse health effects at lower concentrations and over longer
periods of time than was understood when the pre-existing 1-hour ozone
NAAQS was set. EPA determined that the 8-hour NAAQS would be more
protective of human health, especially children and adults who are
active outdoors, and individuals with a pre-existing respiratory
disease, such as asthma.
---------------------------------------------------------------------------
\2\ In March 2008, EPA completed another review of the primary
and secondary ozone NAAQS and tightened them further by lowering the
level for both to 0.075 ppm. See 73 FR 16436 (March 27, 2008).
Additionally, in October 2015, EPA completed a review of the primary
and secondary ozone NAAQS and tightened them by lowering the level
for both to 0.070 ppm. See 80 FR 65292 (October 26, 2015).
---------------------------------------------------------------------------
Following promulgation of a new or revised NAAQS, EPA is required
by the CAA to designate areas throughout the nation as attaining or not
attaining the NAAQS. On April 15, 2004, EPA designated the Clarksville-
Hopkinsville Area, which included Montgomery County, Tennessee, and
Christian County, Kentucky, as nonattainment for the 1997 8-hour ozone
NAAQS, and the designation became effective on June 15, 2004. See 69 FR
23858 (April 30, 2004). Similarly, on May 21, 2012, EPA designated
areas as unclassifiable/attainment or nonattainment for the 2008 8-hour
ozone NAAQS. EPA designated Montgomery County as unclassifiable/
attainment for the 2008 8-hour ozone NAAQS. This designation became
effective on July 20, 2012. See 77 FR 30088 (May 21, 2012). In
addition, on November 16, 2017, areas were designated for the 2015 8-
hour ozone NAAQS. The Montgomery County Area was designated attainment/
unclassifiable for the 2015 8-hour ozone NAAQS, with an effective date
of January 16, 2018. See 82 FR 54232 (November 16, 2017).
A state may submit a request to redesignate a nonattainment area
that is attaining a NAAQS to attainment, and, if the area has met other
required criteria described in section 107(d)(3)(E) of the CAA, EPA may
approve the redesignation request.\3\ One of the criteria for
redesignation is to have an approved maintenance plan under CAA section
175A. The maintenance plan must demonstrate that the area will continue
to maintain the NAAQS for the period extending ten years after
redesignation, and it must contain such additional measures as
necessary to ensure maintenance and such contingency provisions as
necessary to assure that violations of the NAAQS will be promptly
corrected. Eight years after the effective date of redesignation, the
state must also submit a second maintenance plan to ensure ongoing
maintenance of the NAAQS for an additional ten years pursuant to CAA
section 175A(b) (i.e., ensuring maintenance for 20 years after
redesignation).
---------------------------------------------------------------------------
\3\ Section 107(d)(3)(E) of the CAA sets out the requirements
for redesignating a nonattainment area to attainment. They include
attainment of the NAAQS, full approval of the applicable SIP
pursuant to CAA section 110(k), determination that improvement in
air quality is a result of permanent and enforceable reductions in
emissions, demonstration that the state has met all applicable
section 110 and part D requirements, and a fully approved
maintenance plan under CAA section 175A.
---------------------------------------------------------------------------
EPA has published long-standing guidance for states on developing
maintenance plans.\4\ The Calcagni memo provides that states may
generally demonstrate maintenance by either performing air quality
modeling to show that the future mix of sources and emission rates will
not cause a violation of the NAAQS or by showing that projected future
emissions of a pollutant and its precursors will not exceed the level
of emissions during a year when the area was attaining the NAAQS (i.e.,
attainment year inventory). See Calcagni memo at page 9. EPA clarified
in three subsequent guidance memos that certain areas could meet the
CAA section 175A requirement to provide for maintenance by showing that
the area was unlikely to violate the NAAQS in the future, using
information such as the area's design value \5\ being significantly
below the standard and the area having a historically stable design
value.\6\ EPA refers to a maintenance plan containing this streamlined
demonstration as an LMP.
---------------------------------------------------------------------------
\4\ John Calcagni, Director, Air Quality Management Division,
EPA Office of Air Quality Planning and Standards (OAQPS),
``Procedures for Processing Requests to Redesignate Areas to
Attainment,'' September 4, 1992 (Calcagni memo).
\5\ The ozone design value for a monitoring site is the 3-year
average of the annual fourth-highest daily maximum 8-hour average
ozone concentrations. The design value for an ozone area is the
highest design value of any monitoring site in the area.
\6\ See ``Limited Maintenance Plan Option for Nonclassifiable
Ozone Nonattainment Areas,'' from Sally L. Shaver, OAQPS, November
16, 1994; ``Limited Maintenance Plan Option for Nonclassifiable CO
Nonattainment Areas,'' from Joseph Paisie, OAQPS, October 6, 1995;
and ``Limited Maintenance Plan Option for Moderate PM<INF>10</INF>
Nonattainment Areas,'' from Lydia Wegman, OAQPS, August 9, 2001.
Copies of these guidance memoranda can be found in the docket for
this proposed rulemaking.
---------------------------------------------------------------------------
EPA has interpreted CAA section 175A as permitting the LMP option
because section 175A of the Act does not define how areas may
demonstrate maintenance, and in EPA's experience implementing the
various NAAQS, areas that qualify for an LMP and have approved LMPs
have rarely, if ever, experienced subsequent violations of the NAAQS.
As noted in the LMP guidance memoranda, states seeking an LMP must
still submit the other maintenance plan elements outlined in the
Calcagni memo, including: An attainment emissions inventory, provisions
for the continued operation of the ambient air quality monitoring
network, verification of continued attainment, and a contingency plan
in the event of a future violation of the NAAQS. Moreover, a state
seeking an
[[Page 52866]]
LMP must still submit its section 175A maintenance plan as a revision
to its SIP, with all attendant notice and comment procedures. While the
LMP guidance memoranda were originally written with respect to certain
NAAQS,\7\ EPA has extended the LMP interpretation of section 175A to
other NAAQS and pollutants not specifically covered by the previous
guidance memos.\8\
---------------------------------------------------------------------------
\7\ The prior memos addressed: Unclassifiable areas under the 1-
hour ozone NAAQS, nonattainment areas for the PM<INF>10</INF>
(particulate matter with an aerodynamic diameter less than 10
microns) NAAQS, and nonattainment for the carbon monoxide (CO)
NAAQS.
\8\ See, e.g., 79 FR 41900 (July 18, 2014) (approval of the
second ten-year LMP for the Grant County 1971 SO<INF>2</INF>
maintenance area).
---------------------------------------------------------------------------
In this case, EPA is proposing to approve Tennessee's LMP because
the State has made a showing, consistent with EPA's prior LMP guidance,
that the Clarksville-Hopkinsville Area's ozone concentrations are well
below the 1997 8-hour ozone NAAQS and have been historically stable and
that it has met the other maintenance plan requirements. TDEC submitted
this LMP for the Montgomery County Area to fulfill the second
maintenance plan requirement in the Act. EPA's evaluation of the
Montgomery County Area's LMP is presented below.
In August of 2005, TDEC submitted to EPA a request to redesignate
the Montgomery County Area to attainment for the 1997 8-hour ozone
NAAQS. This submittal included a plan to provide for maintenance of the
1997 8-hour ozone NAAQS in Montgomery County through 2016 as a revision
to the Tennessee SIP. EPA approved the Montgomery County Area's
Maintenance Plan and the State's request to redesignate the Montgomery
County Area to attainment for the 1997 8-hour ozone NAAQS, effective
November 21, 2005. See 70 FR 55559 (September 22, 2005).
Under CAA section 175A(b), states must submit a revision to the
first maintenance plan eight years after redesignation to provide for
maintenance of the NAAQS for ten additional years following the end of
the first 10-year period. EPA's final implementation rule for the 2008
8-hour ozone NAAQS revoked the 1997 8-hour ozone NAAQS and stated that
one consequence of revocation was that areas that had been redesignated
to attainment (i.e., maintenance areas) for the 1997 NAAQS no longer
needed to submit second 10-year maintenance plans under CAA section
175A(b). See 80 FR 12264, 12315 (March 6, 2015).
In South Coast Air Quality Management District v. EPA, the United
States Court of Appeals for the District of Columbia Circuit (D.C.
Circuit) vacated the EPA's interpretation that, because of the
revocation of the 1997 8-hour ozone NAAQS, second maintenance plans
were not required for ``orphan maintenance areas,'' i.e., areas that
had been redesignated to attainment for the 1997 8-hour ozone NAAQS
maintenance areas and were designated attainment for the 2008 ozone
NAAQS. South Coast, 882 F.3d 1138 (D.C. Cir. 2018). Thus, states with
these ``orphan maintenance areas'' under the 1997 8-hour ozone NAAQS
must submit maintenance plans for the second maintenance period.
Accordingly, on June 23, 2020, Tennessee submitted a second maintenance
plan for the Montgomery County Area that shows that the Area is
expected to remain in attainment of the 1997 8-hour ozone NAAQS through
2025.
In recognition of the continuing record of air quality monitoring
data showing ambient 8-hour ozone concentrations in the Clarksville-
Hopkinsville Area well below the 1997 8-hour ozone NAAQS, TDEC chose
the LMP option for the development of a second 1997 8-hour ozone NAAQS
maintenance plan. On June 10, 2020, TDEC adopted the second 10-year
1997 8-hour ozone maintenance plan, and on June 23, 2020, TDEC
submitted the Montgomery County Area LMP to EPA as a revision to the
Tennessee SIP.
III. Tennessee's SIP Submittal
As mentioned above, on June 23, 2020, TDEC submitted the Montgomery
County Area 1997 8-Hour Ozone NAAQS LMP to EPA as a revision to the
Tennessee SIP. The submittal includes the LMP, air quality data,
emissions inventory information, and appendices, as well as
certification of adoption of the plan by TDEC. Appendices to the plan
include comments and responses between EPA and TDEC; documentation of
notice, hearing, and public participation prior to adoption of the plan
by the TDEC on June 10, 2020; interagency consultation; and Air
Pollution Control Board order, which notes that Tennessee's LMP
submittal for the remainder of the 20-year maintenance period for the
for the Montgomery County Area is in response to the D.C. Circuit's
decision overturning aspects of EPA's implementation rule for the 2008
8-hour ozone NAAQS. The Montgomery County Area LMP does not include any
additional emissions reduction measures but relies on the same emission
reduction strategy as the first 10-year Maintenance Plan that provides
for maintenance of the 1997 ozone NAAQS through 2016. The measures upon
which the second 10-year LMP for the Montgomery County Area relies
include the SIP-approved version of Tennessee Air Pollution Control
Regulation 1200-03-27-.12, NO<INF>X</INF> SIP Call Requirements for
Stationary Boilers and Combustion Turbines, which established a state
control program for sources that are subject to the NO<INF>X</INF> SIP
Call but not covered under Cross State Air Pollution Rule (CSAPR).\9\
The LMP also relies on continued implementation of federal measures
(e.g., interstate transport rules such as CSAPR, see 76 FR 48208
(August 8, 2011), and the CSAPR Update, see 81 FR 74504 (October 26,
2016)).
---------------------------------------------------------------------------
\9\ See 86 FR 12092 (March 2, 2021).
---------------------------------------------------------------------------
IV. EPA's Evaluation of Tennessee's SIP Submittal
EPA has reviewed the Montgomery County Area's LMP which is designed
to maintain the 1997 8-hour ozone NAAQS within Montgomery County
through the end of the 20-year period beyond redesignation, as required
under CAA section 175A(b). The following is a summary of EPA's
interpretation of the section 175A requirements \10\ and EPA's
evaluation of how each requirement is met.
---------------------------------------------------------------------------
\10\ See Calcagni memo.
---------------------------------------------------------------------------
A. Attainment Emissions Inventory
For maintenance plans, a state should develop a comprehensive,
accurate inventory of actual emissions for an attainment year to
identify the level of emissions which is sufficient to maintain the
NAAQS. A state should develop this inventory consistent with EPA's most
recent guidance on emissions inventory development. For ozone, the
inventory should be based on typical summer day emissions of VOCs and
NO<INF>X</INF>, as these pollutants are precursors to ozone formation.
The Montgomery County Area LMP includes an ozone attainment inventory
for Montgomery County that reflects typical summer day emissions in
2014. Table 1 presents a summary of the inventory for 2014 contained in
the LMP.
[[Page 52867]]
Table 1--2014 Typical Summer Day 8-Hour Ozone Emissions for the
Montgomery County Area
[Tons/summer day]
------------------------------------------------------------------------
NOX emissions
Source category VOC emissions
------------------------------------------------------------------------
Fire.................................... * 0.00 * 0.00
Nonpoint................................ 8.79 0.90
Nonroad................................. 1.58 1.35
Onroad.................................. 4.76 7.64
Point................................... 0.97 0.50
-------------------------------
Total............................... * 16.10 10.39
------------------------------------------------------------------------
* This Total VOC Emissions value differs from Tennessee's submittal and
has been re-calculated by TDEC to accurately reflect the total VOC
emissions for Montgomery County.\11\
The Emissions Inventory section of the Montgomery County Area's LMP
describes the methods, models, and assumptions used to develop the
attainment inventory. As described in the Emissions Inventory section
of the LMP, TDEC generally relied upon emissions inventory information
from the EPA 2014 version 7.0 air quality modeling platform (2014v7.0
platform), which is based on the 2014 NEI. The emissions data in the
2014v7.0 platform are primarily based on the 2014NEIv1 for point
sources, nonpoint sources, commercial marine vessels (CMV), onroad and
nonroad mobile sources, and fires. This 2014 modeling platform includes
all criteria air pollutants (CAPs) and precursors and two groups of
hazardous air pollutants (HAPs).
---------------------------------------------------------------------------
\11\ See email from James Johnston, TDEC, to Lynorae Benjamin,
EPA Region 4, on December 15, 2020, available in the docket for this
proposed rulemaking.
---------------------------------------------------------------------------
Nonroad mobile source emissions in the 2014NEIv1, in part, were
estimated using the latest version of the EPA's motor vehicle emissions
model, MOVES 2014a (which includes estimates of nonroad emissions like
agriculture, commercial and mining, industrial and recreational
equipment, and commercial and residential lawn and garden equipment).
Locomotives, aircraft, and marine nonroad sources are not included in
MOVES, and TDEC relied on EPA-generated emissions for these
sectors.\12\ Onroad mobile sources in the 2014NEIv1 were estimated
using MOVES 2014a and the latest planning assumptions regarding vehicle
type, activity, and vehicle speeds to estimate vehicular emissions for
2014. MOVES2014a was used with inputs, where provided, by state and
local agencies, in combination with EPA-generated default data. In its
entirety, the 2014v7.0 platform's set of estimates for vehicles
reflects emissions inventories and ancillary data files used for
emissions modeling, as well as the meteorological, initial condition,
and boundary condition files needed to run the air quality model.
---------------------------------------------------------------------------
\12\ EPA developed emissions for these sectors based on AP-42
emissions factor, and information supplied by the Eastern Regional
Technical Advisory Committee for locomotives and Federal Aviation
Administration's Emissions and Dispersion Modeling System (since
replaced by the Aviation Environmental Design Tool).
---------------------------------------------------------------------------
B. Maintenance Demonstration
The maintenance demonstration requirement is considered to be
satisfied in an LMP if the state can provide sufficient weight of
evidence indicating that air quality in the area is well below the
level of the NAAQS, that past air quality trends have been shown to be
stable, and that the probability of the area experiencing a violation
over the second 10-year maintenance period is low.\13\ These criteria
are evaluated below with regard to the Clarksville-Hopkinsville Area as
a whole.
---------------------------------------------------------------------------
\13\ See footnote 4.
---------------------------------------------------------------------------
1. Evaluation of Ozone Air Quality Levels
To attain the 1997 8-hour ozone NAAQS, the three-year average of
the fourth-highest daily maximum 8-hour average ozone concentrations
(design value) at each monitor within an area must not exceed 0.08 ppm.
Based on the rounding convention described in 40 CFR part 50, Appendix
I, the NAAQS is attained if the design value is 0.084 ppm or below.
There is currently one monitor measuring ozone, located within
Christian County, Kentucky, which provides air quality data for the
entire Clarksville-Hopkinsville Area. At the time of submission, EPA
evaluated quality assured and certified 2016-2018 monitoring data \14\
and determined that the design value for the Clarksville-Hopkinsville
Area was 0.060 ppm, or 71 percent of the level of the 1997 8-hour ozone
NAAQS. Based on quality assured and certified monitoring data for 2018-
2020,\15\ the current design value for the Clarksville-Hopkinsville
Area is 0.058 ppm, or 69 percent of the level of the 1997 8-hour ozone
NAAQS. Consistent with prior guidance, EPA believes that if the most
recent air quality design value for the area is at a level that is well
below the NAAQS (e.g., below 85 percent of the NAAQS, or in this case,
below 0.071 ppm), then EPA considers the state to have met the section
175A requirement for a demonstration that the area will maintain the
NAAQS for the requisite period. Such a demonstration assumes continued
applicability of prevention of significant deterioration requirements
and any control measures already in the SIP and that Federal measures
will remain in place through the end of the second 10-year maintenance
period, absent a showing consistent with section 110(l) that such
measures are not necessary to assure maintenance.
---------------------------------------------------------------------------
\14\ See the spreadsheet titled ``Ozone Design Values, 2018
(XLXS)'' at <a href="https://www.epa.gov/air-trends/air-quality-design-values#report">https://www.epa.gov/air-trends/air-quality-design-values#report</a>.
\15\ See the spreadsheet titled ``Ozone Design Values, 2020
(XLXS)'' at <a href="https://www.epa.gov/air-trends/air-quality-design-values#report">https://www.epa.gov/air-trends/air-quality-design-values#report</a>.
---------------------------------------------------------------------------
Tables 2a and 2b present the design values for the Clarksville-
Hopkinsville Area over the 2007-2020 period. As shown in Tables 2a and
2b, the Hopkinsville monitor has been well below the level of the 1997
8-hour ozone NAAQS since the Area was redesignated to attainment, and
the most current design value is below the level of 85 percent of the
NAAQS, consistent with prior LMP guidance.
[[Page 52868]]
Table 2a--1997 8-Hour Ozone NAAQS Design Values (ppm) at the Monitoring Site in the Clarksville-Hopkinsville, TN-KY Area for the 2007-2013 Time Period
--------------------------------------------------------------------------------------------------------------------------------------------------------
AQS Site 2005-2007 2006-2008 2007-2009 2008-2010 2009-2011 2010-2012 2011-2013
Location County State ID DV DV DV DV DV DV DV
--------------------------------------------------------------------------------------------------------------------------------------------------------
Hopkinsville.................. Christian....... KY 21-047-000 0.081 0.078 * 0.074 0.069 0.070 0.073 0.069
6
--------------------------------------------------------------------------------------------------------------------------------------------------------
Table 2b--1997 8-Hour Ozone NAAQS Design Values (ppm) at the Monitoring Site in the Clarksville-Hopkinsville, TN-KY Area for the 2014-2020 Time Period
--------------------------------------------------------------------------------------------------------------------------------------------------------
AQS Site 2012-2014 2013-2015 2014-2016 2015-2017 2016-2018 2017-2019 2018-2020
Location County State ID DV DV DV DV DV DV DV
--------------------------------------------------------------------------------------------------------------------------------------------------------
Hopkinsville.................. Christian....... KY 21-047-000 0.067 0.063 0.062 0.061 0.060 0.058 0.058
6
--------------------------------------------------------------------------------------------------------------------------------------------------------
* The Hopkinsville, KY site (AQS ID: 21-047-0006) was operated by the Tennessee Valley Authority (TVA) until 2008. In 2008, the Kentucky Division for
Air Quality began operation of an ozone monitor at the site (designated in AQS as Parameter Occurrence Code (POC) 2), and TVA discontinued operation
of its POC 1 ozone monitor at the end of 2008. Both monitors met completeness requirements for the years that they operated during 2007-2009. AQS does
not combine data from different POCs when calculating a design value for the 1997 Ozone NAAQS. However, to accurately present the data in the Table, a
2007-2009 design value was calculated using the combined datasets from the TVA and KY monitors. In 2008, when both monitors collected complete data,
the KY monitor data was used because it is flagged as certified in AQS, while the 2008 TVA data is not. The combined 2007-2009 DV using 2007 data from
the TVA monitor and 2008-2009 data from the KY monitor is 74 parts per billion and is shown in the Table.
Therefore, the Montgomery County Area is eligible for the LMP
option, and EPA proposes to find that the long record of monitored
ozone concentrations that attain the NAAQS, together with the
continuation of existing VOC and NOx emissions control programs,
adequately provide for the maintenance of the 1997 8-hour ozone NAAQS
in Montgomery County through the second 10-year maintenance period and
beyond.
Additional supporting information that the Area is expected to
continue to maintain the NAAQS can be found in projections of future
year design values that EPA recently completed to assist states with
development of interstate transport SIPs for the 2015 ozone NAAQS.\16\
Those projections, made for the year 2023, show that the highest design
value in the Clarksville-Hopkinsville Area is expected to be 0.056 ppm.
---------------------------------------------------------------------------
\16\ See the spreadsheet titled ``Ozone Monitoring Site Design
Values for 2008 through 2017 and for 2023'' at <a href="https://www.epa.gov/airmarkets/memo-and-supplemental-information-regarding-interstate-transport-sips-2015-ozone-naaqs">https://www.epa.gov/airmarkets/memo-and-supplemental-information-regarding-interstate-transport-sips-2015-ozone-naaqs</a>.
---------------------------------------------------------------------------
2. Stability of Ozone Levels
As discussed above, the Montgomery County Area has maintained air
quality well below the 1997 8-hour ozone NAAQS over the past thirteen
years. Additionally, the design value data shown within Tables 2a and
2b illustrates that ozone levels have been relatively stable over this
timeframe, with an overall downward trend. For example, the data within
Tables 2a and 2b indicates that the largest year over year change in
design value at any one monitor during these thirteen years was five
parts per billion which occurred between the 2007-2009 design value and
the 2008-2010 design value, and it represented only a six percent
change. Furthermore, the overall trend in design values for the
Clarksville-Hopkinsville Area between 2007-2020 shows a decrease of 23
parts per billion at the Hopkinsville monitor (AQS Site ID 21-047-
0006). This downward trend in ozone levels, coupled with the relatively
small, year-over-year variation in ozone design values, makes it
reasonable to conclude that Montgomery County Area will not exceed the
1997 8-hour ozone NAAQS during the second 10-year maintenance period.
3. Projected Emissions
Although under the LMP option there is no requirement to project
emissions over the maintenance period, TDEC included an analysis of
ozone precursor emissions trends expected over the course of the second
10-year maintenance period. TDEC provided a VOC and NOx emissions
trends analysis from 2014 to 2028. Tennessee selected 2014 as a
baseline for the projection because that is the most recent year for
which a complete set of data was available from EPA's National
Emissions Inventory (NEI) database at the time the State developed its
second maintenance plan for the Area.\17\ Projected emissions data for
the year 2028 were obtained from EPA,\18\ and these data represent EPA
emissions projections that are available for a date furthest out into
the future.\19\ The emissions projection trends show that between 2014
and 2028, VOC emissions are estimated to fall by approximately 43
percent, and NOx emissions are estimated to fall by approximately 56
percent within the Montgomery County Area. These projected declining
emissions trends further support the conclusion that it is unlikely
that the Area would violate the 1997 8-hour ozone NAAQS in the future.
Table 3 presents a summary of projected emissions for 2028 contained in
the maintenance plan.
---------------------------------------------------------------------------
\17\ The 2017 NEI is the most recent NEI, but it was unavailable
to Tennessee when the State developed its SIP revision.
\18\ The projected emissions data is available at <a href="https://www.epa.gov/air-emissions-modeling/2014-2016-version-7-air-emissions-modeling-platforms">https://www.epa.gov/air-emissions-modeling/2014-2016-version-7-air-emissions-modeling-platforms</a>.
\19\ EPA's emissions projections to 2028 were made from the 2011
NEI, as that iteration of the NEI was the most recently available
version when the projection work was performed.
Table 3--2028 Typical Summer Day 8-Hour Ozone Emissions for the
Montgomery County Area
[tons/day]
------------------------------------------------------------------------
NOX emissions
Source category VOC emissions
------------------------------------------------------------------------
Fire.................................... 0.58 0.02
Nonpoint................................ 5.31 1.36
[[Page 52869]]
Nonroad................................. 1.12 0.67
Onroad.................................. 1.43 2.15
Point................................... 0.73 0.31
-------------------------------
Total............................... 9.17 4.51
------------------------------------------------------------------------
C. Monitoring Network and Verification of Continued Attainment
EPA periodically reviews the ozone monitoring network that the
Commonwealth of Kentucky operates and maintains in Christian County, in
accordance with 40 CFR part 58. This network plan, which is submitted
annually to EPA, is consistent with the ambient air monitoring network
assessment. The annual network plan developed by the Kentucky Division
for Air Quality (KDAQ) follows a public notification and review
process. EPA has reviewed and approved the 2020 Ambient Air Monitoring
Network Plan (``2020 Annual Network Plan'').\20\
---------------------------------------------------------------------------
\20\ Kentucky's network plan is available at <a href="https://www.tn.gov/content/dam/tn/environment/air/documents/apcairqualitymonitoring/2020%20Tennessee%20Annual%20Monitoring%20Network%20Plan%20-%20Comment%20Update.pdf">https://www.tn.gov/content/dam/tn/environment/air/documents/apcairqualitymonitoring/2020%20Tennessee%20Annual%20Monitoring%20Network%20Plan%20-%20Comment%20Update.pdf</a>.
---------------------------------------------------------------------------
To verify the attainment status of the area over the maintenance
period, the maintenance plan should contain provisions for continued
operation of an appropriate, EPA-approved monitoring network in
accordance with 40 CFR part 58. As noted above, KDAQ's monitoring
network in the Clarksville-Hopkinsville Area has been approved by EPA
in accordance with 40 CFR part 58, and Kentucky committed, in its SIP-
approved maintenance plan,\21\ to continue to maintain a network in
accordance with EPA requirements. TDEC supports continued ozone
monitoring by KDAQ. EPA proposes to find that KDAQ's monitoring network
is adequate to verify continued attainment of the 1997 8-hour ozone
NAAQS in the Montgomery County Area.
---------------------------------------------------------------------------
\21\ See 71 FR 4047 (January 25, 2006).
---------------------------------------------------------------------------
D. Contingency Plan
Section 175A(d) of the Act requires that a maintenance plan include
contingency provisions. The purpose of such contingency provisions is
to prevent future violations of the NAAQS or to promptly remedy any
NAAQS violations that might occur during the maintenance period. These
contingency measures are required to be implemented expeditiously once
they are triggered by a future violation of the NAAQS or some other
trigger. The state should identify specific triggers which will be used
to determine when the contingency measures need to be implemented.
The LMP states that the trigger is a Quality Assured/Quality
Controlled (QA/QC) violating design value of the 1997 8-hour ozone
NAAQS in the Clarksville-Hopkinsville Area.\22\ If this trigger is
activated, the maintenance plan requires Tennessee to conduct a study
to determine the cause of the higher ozone value, whether from an event
not likely to recur or from an increasing trend in emissions that
threatens the continued maintenance of the NAAQS. Tennessee will adopt
and implement appropriate contingency measures tailored to the source
of the violation (or increased concentrations) as expeditiously as
practicable, but no later than 18 to 24 months after the trigger
event.\23\
---------------------------------------------------------------------------
\22\ If QA/QC data indicates a violating design value for the 8-
hour ozone NAAQS, then the triggering event will be the date of the
design value violation, and not the final QA/QC date. However, if
initial monitoring data indicates a possible design value violation
but later QA/QC indicates that a NAAQS violation did not occur, then
a triggering event will not have occurred, and contingency measures
will not need to be implemented.
\23\ See the Contingency Plan section of the LMP for further
information regarding the contingency plan, including measures that
Tennessee will consider for adoption if the trigger is activated.
---------------------------------------------------------------------------
EPA proposes to find that the contingency provisions in Tennessee's
second maintenance plan for the 1997 8-hour Ozone NAAQS meet the
requirements of the CAA section 175A(d).
E. Conclusion
EPA proposes to find that the Montgomery County Area LMP for the
1997 8-hour ozone NAAQS includes an approvable update of the various
elements (including attainment inventory, assurance of adequate
monitoring and verification of continued attainment, and contingency
provisions) of the initial EPA-approved Maintenance Plan for the 1997
8-hour ozone NAAQS. EPA also proposes to find that the Montgomery
County Area, qualifies for the LMP option, and adequately demonstrates
maintenance of the 1997 8-hour ozone NAAQS through the documentation of
monitoring data showing maximum 1997 8-hour ozone levels well below the
NAAQS and historically stable design values. EPA believes the
Montgomery County Area's LMP, which retains all existing control
measures in the SIP, is sufficient to provide for maintenance of the
1997 8-hour ozone NAAQS in Montgomery County over the second
maintenance period (i.e., through 2025) and thereby satisfies the
requirements for such a plan under CAA section 175A(b). EPA is
therefore proposing to approve Tennessee's June 23, 2020, submission of
the Montgomery County Area's LMP as a revision to the Tennessee SIP.
V. Transportation Conformity
Transportation conformity is required by section 176(c) of the CAA.
Conformity to a SIP means that transportation activities will not
produce new air quality violations, worsen existing violations, or
delay timely attainment of the NAAQS. See CAA 176(c)(1)(A) and (B).
EPA's transportation conformity rule at 40 CFR part 93 subpart A
requires that transportation plans, programs, and projects conform to
SIPs and establishes the criteria and procedures for determining
whether they conform. The conformity rule generally requires a
demonstration that emissions from the Regional Transportation Plan
(RTP) and the Transportation Improvement Program (TIP) are consistent
with the motor vehicle emissions budget (MVEB) contained in the control
strategy SIP revision or maintenance plan. See 40 CFR 93.101, 93.118,
and 93.124. A MVEB is defined as ``the portion of the total allowable
emissions defined in the submitted or approved control strategy
implementation plan revision or maintenance plan for a certain date for
the purpose of meeting reasonable further progress milestones or
demonstrating attainment or maintenance of the NAAQS, for any criteria
pollutant or its precursors,
[[Page 52870]]
allocated to highway and transit vehicle use and emissions.'' See 40
CFR 93.101.
Under the conformity rule, LMP areas may demonstrate conformity
without a regional emissions analysis. See 40 CFR 93.109(e). On
September 22, 2005, EPA made a finding that the MVEBs for the first 12
years of the 1997 8-hour ozone maintenance plan for the Montgomery
County Area were adequate for transportation conformity purposes. In a
Federal Register notice dated September 22, 2005, EPA notified the
public of that finding. See 70 FR 55559. These new MVEBs became
effective November 21, 2005. After approval of this LMP or an adequacy
finding for this LMP, there is no requirement to meet the budget test
pursuant to the transportation conformity rule for the maintenance
area. All actions that would require a transportation conformity
determination for the Montgomery County Area under EPA's transportation
conformity rule provisions are considered to have already satisfied the
regional emissions analysis and ``budget test'' requirements in 40 CFR
93.118 as a result of EPA's adequacy finding for the LMP. See 69 FR
40004 (July 1, 2004).
However, because LMP areas are still maintenance areas, certain
aspects of transportation conformity determinations still will be
required for transportation plans, programs, and projects.
Specifically, for such determinations, RTPs, TIPs and transportation
projects still will have to demonstrate that they are fiscally
constrained (40 CFR 93.108) and meet the criteria for consultation (40
CFR 93.105) and Transportation Control Measure implementation in the
conformity rule provisions (40 CFR 93.113) as well as meet the hot-spot
requirements for projects (40 CFR 93.116).\24\ Additionally, conformity
determinations for RTPs and TIPs must be determined no less frequently
than every four years, and conformity of plan and TIP amendments and
transportation projects is demonstrated in accordance with the timing
requirements specified in 40 CFR 93.104. In addition, in order for
projects to be approved they must come from a currently conforming RTP
and TIP. See 40 CFR 93.114 and 40 CFR 93.115.
---------------------------------------------------------------------------
\24\ A conformity determination that meets other applicable
criteria in Table 1 of paragraph (b) of this section (93.109(e)) is
still required, including the hot-spot requirements for projects in
CO, PM<INF>10</INF>, and fine particulate matter (PM<INF>2.5</INF>)
areas.
---------------------------------------------------------------------------
VI. Proposed Action
Under sections 110(k) and 175A of the CAA and for the reasons set
forth above, EPA is proposing to approve the Montgomery County Area LMP
for the 1997 8-hour ozone NAAQS, submitted by TDEC on June 23, 2020, as
a revision to the Tennessee SIP. EPA is proposing to approve the
Montgomery County Area LMP because it includes an acceptable update of
the various elements of the 1997 8-hour ozone NAAQS Maintenance Plan
approved by EPA for the first 10-year period (including emissions
inventory, assurance of adequate monitoring and verification of
continued attainment, and contingency provisions), and retains the
relevant provisions of the SIP.
EPA also finds that the Montgomery County Area qualifies for the
LMP option and that, therefore, the Montgomery County Area's LMP
adequately demonstrates maintenance of the 1997 8-hour ozone NAAQS
through documentation of monitoring data showing maximum 1997 8-hour
ozone levels well below the NAAQS and continuation of existing control
measures. EPA believes that the Montgomery County Area's 1997 8-Hour
Ozone LMP is sufficient to provide for maintenance of the 1997 8-hour
ozone NAAQS in Montgomery County over the second 10-year maintenance
period, through 2025, and thereby satisfy the requirements for such a
plan under CAA section 175A(b).
VII. 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. See 42 U.S.C. 7410(k); 40 CFR 52.02(a). Thus, in
reviewing SIP submissions, EPA's role is to approve state choices,
provided that they meet the criteria of the CAA. 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 proposed action:
<bullet> 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);
<bullet> Does not impose an information collection burden under the
provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.);
<bullet> 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.);
<bullet> 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);
<bullet> Does not have Federalism implications as specified in
Executive Order 13132 (64 FR 43255, August 10, 1999);
<bullet> Is not an economically significant regulatory action based
on health or safety risks subject to Executive Order 13045 (62 FR
19885, April 23, 1997);
<bullet> Is not a significant regulatory action subject to
Executive Order 13211 (66 FR 28355, May 22, 2001);
<bullet> 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
<bullet> 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).
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 rule does
not have tribal implications as specified by Executive Order 13175 (65
FR 67249, November 9, 2000), nor will it impose substantial direct
costs on tribal governments or preempt tribal law.
List of Subjects in 40 CFR Part 52
Environmental protection, Air pollution control, Incorporation by
reference, Intergovernmental relations, Nitrogen oxides, Ozone,
Reporting and recordkeeping requirements, Volatile organic compounds.
Authority: 42 U.S.C. 7401 et seq.
Dated: September 1, 2021.
John Blevins,
Acting Regional Administrator, Region 4.
[FR Doc. 2021-20349 Filed 9-22-21; 8:45 am]
BILLING CODE 6560-50-P
</pre><script data-cfasync="false" src="/cdn-cgi/scripts/5c5dd728/cloudflare-static/email-decode.min.js"></script></body>
</html>Indexed from Federal Register on September 23, 2021.
This is legal information, not legal advice. Laws vary by jurisdiction and change frequently. Always verify current law with official sources and consult a licensed attorney in your jurisdiction for advice on your specific situation.