Proposed Rule2021-19801
Air Plan Approval; ID; West Silver Valley Redesignation to Attainment for the 2012 Annual PM2.5
Primary source
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Published
September 15, 2021
Issuing agencies
Environmental Protection Agency
Abstract
The Environmental Protection Agency (EPA) is proposing to redesignate the West Silver Valley, Idaho nonattainment area to attainment for the 2012 annual fine particulate matter (PM<INF>2.5</INF>) National Ambient Air Quality Standard (NAAQS). EPA is also proposing to approve a maintenance plan for the area demonstrating continued compliance with the NAAQS through 2031, which the Idaho Department of Environmental Quality (IDEQ) submitted along with the redesignation request on June 2, 2020, for inclusion into the Idaho State Implementation Plan (SIP). Additionally, EPA is proposing to approve the 2031 motor vehicle emissions budgets included in Idaho's maintenance plan for PM<INF>2.5</INF>, nitrogen oxides (NO<INF>X</INF>) and volatile organic compounds (VOCs). EPA is proposing this action pursuant to the Clean Air Act (CAA or the Act).
Full Text
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<title>Federal Register, Volume 86 Issue 176 (Wednesday, September 15, 2021)</title>
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[Federal Register Volume 86, Number 176 (Wednesday, September 15, 2021)]
[Proposed Rules]
[Pages 51318-51326]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2021-19801]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Parts 52 and 81
[EPA-R10-OAR-2020-0305; FRL-8878-01-R10]
Air Plan Approval; ID; West Silver Valley Redesignation to
Attainment for the 2012 Annual PM2.5 Standard
AGENCY: Environmental Protection Agency (EPA).
ACTION: Proposed rule.
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SUMMARY: The Environmental Protection Agency (EPA) is proposing to
redesignate the West Silver Valley, Idaho nonattainment area to
attainment for the 2012 annual fine particulate matter
(PM<INF>2.5</INF>) National Ambient Air Quality Standard (NAAQS). EPA
is also proposing to approve a maintenance plan for the area
demonstrating continued compliance with the NAAQS through 2031, which
the Idaho Department of Environmental Quality (IDEQ) submitted along
with the redesignation request on June 2, 2020, for inclusion into the
Idaho State Implementation Plan (SIP). Additionally, EPA is proposing
to approve the 2031 motor vehicle emissions budgets included in Idaho's
maintenance plan for PM<INF>2.5</INF>, nitrogen oxides (NO<INF>X</INF>)
and volatile organic compounds (VOCs). EPA is proposing this action
pursuant to the Clean Air Act (CAA or the Act).
DATES: Comments must be received on or before October 15, 2021.
ADDRESSES: Submit your comments, identified by Docket ID No. EPA-R10-
OAR-2020-0305, at <a href="https://www.regulations.gov">https://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 electronically submit any
information you consider to be Confidential Business Information (CBI)
or other information the disclosure of which is restricted by statute.
Multimedia submissions (audio, video, etc.) must be accompanied by a
written comment. The written comment is considered the official comment
and should include discussion of all points you wish to make. 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="https://www.epa.gov/dockets/commenting-epa-dockets">https://www.epa.gov/dockets/commenting-epa-dockets</a>.
FOR FURTHER INFORMATION CONTACT: Claudia Vaupel, (206) 553-6121,
<a href="/cdn-cgi/l/email-protection#a0d6c1d5c5d0cc8ec3ccc1d5c4c9c1e0c5d0c18ec7cfd6"><span class="__cf_email__" data-cfemail="146275617164783a77787561707d75547164753a737b62">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION: Throughout this document whenever ``we,''
``us,'' or ``our'' is used, it is intended to refer to EPA.
Table of Contents
I. Background
II. Requirements for Redesignation to Attainment
III. EPA's Analysis of Idaho's Submittal
A. Attainment Determination
B. Applicable Requirements Under Section 110 and Part D of the
CAA
1. CAA Section 110 General SIP Requirements
2. Part D of Title I Requirements
C. Improvement in Air Quality Due to Permanent and Enforceable
Measures
D. Fully Approved Maintenance Plan
1. Attainment Inventory
2. Maintenance Demonstration
3. Monitoring Network
4. Verification of Continued Attainment
5. Contingency Plan
E. Requirements for Transportation Conformity and Motor Vehicle
Emissions Budgets (MVEBs)
IV. Proposed Action
V. Statutory and Executive Order Reviews
I. Background
On December 14, 2012, EPA promulgated a revised primary annual
PM<INF>2.5</INF> NAAQS to provide increased protection of public health
from fine particle pollution. 78 FR 3086 (January 15, 2013). In that
action, EPA strengthened the primary annual PM<INF>2.5</INF> standard
from 15.0 micrograms per cubic meter (mg/m\3\) to 12.0 mg/m\3\, which
is attained when the 3-year average of the annual arithmetic means does
not exceed 12.0 mg/m\3\. On December 18, 2014, EPA promulgated initial
designations for the 2012 primary PM<INF>2.5</INF> NAAQS based on 2011-
2013 air quality monitoring data for the majority of the United States.
80 FR 2206 (January 15, 2015). In that action, EPA designated the West
Silver Valley in Shoshone County, Idaho as a moderate nonattainment
area for the 2012 annual PM<INF>2.5</INF> NAAQS. See 40 CFR 81.313.
On April 6, 2018, EPA published a ``finding of failure to submit''
required SIP elements for the 2012 annual PM<INF>2.5</INF> NAAQS for
several nonattainment areas nationwide, including the West Silver
Valley in Idaho. See 83 FR 14759. In particular, Idaho failed to submit
the following specific moderate area SIP elements for the West Silver
Valley: An attainment demonstration; control strategies, including
reasonably available control measures (RACM) and reasonably available
control technologies (RACT); a reasonable further progress (RFP) plan;
quantitative milestones; and contingency measures. This finding
triggered the sanctions clock under section 179 of the CAA, as well as
an obligation under section 110(c) of the CAA for EPA to promulgate a
Federal Implementation Plan no later than 2 years from the effective
date of the finding, if Idaho has not submitted, and EPA has not
approved, the required SIP submission.
On December 21, 2018, EPA determined that the West Silver Valley
attained the 2012 annual PM<INF>2.5</INF> NAAQS based on 2015-2017
ambient air quality monitoring data and made a ``clean data
determination.'' 83 FR 65535. A clean data determination suspends
certain planning requirements for the area, including the requirement
to submit an attainment demonstration and associated RACM, including
RACT, an RFP plan, and contingency measures for failure to attain or
meet RFP. These requirements are suspended as long as the area
continues to meet the 2012 annual PM<INF>2.5</INF> NAAQS. When the area
is redesignated to attainment, the requirements are permanently
discharged.
II. Requirements for Redesignation to Attainment
The CAA provides the requirements for redesignating a nonattainment
area to attainment. Specifically, section 107(d)(3)(E) of the CAA, 42
U.S.C. 7407(d)(3)(E), allows for redesignation provided that: (1) EPA
determines that the area has attained the applicable NAAQS; (2) EPA has
fully approved the applicable implementation plan for the area under
section 110(k) of the CAA; (3) EPA determines that the improvement in
air quality is due to permanent and enforceable reductions
[[Page 51319]]
in emissions resulting from implementation of the applicable SIP and
applicable Federal air pollutant control regulations and other
permanent and enforceable reductions; (4) EPA has fully approved a
maintenance plan for the area as meeting the requirements of section
175A of the CAA; and (5) the state containing such area has met all
requirements applicable to the area under section 110 and part D of the
CAA. In this proposed action, EPA will review CAA section 107(d)(3)(E)
requirements (2) and (5) together as part of our evaluation of Idaho's
redesignation request.
EPA has provided guidance on redesignation in the CAA ``General
Preamble,'' \1\ and has provided further guidance on processing
redesignation requests in the following documents: (1) ``Procedures for
Processing Requests to Redesignate Areas to Attainment,'' Memorandum
from John Calcagni, Director, Air Quality Management Division,
September 4, 1992 (Calcagni memorandum); (2) ``State Implementation
Plan (SIP) Actions Submitted in Response to Clean Air Act (CAA)
Deadlines,'' Memorandum from John Calcagni, Director, Air Quality
Management Division, October 28, 1992; and (3) ``Part D New Source
Review (Part D NSR) Requirements for Areas Requesting Redesignation to
Attainment,'' Memorandum from Mary D. Nichols, Assistant Administrator
for Air and Radiation, October 14, 1994. These documents are included
in the docket for this proposed action.
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\1\ See ``State Implementation Plans; General Preamble for the
Implementation of Title I of the Clean Air Act Amendments of 1990,''
57 FR 13498, April 16, 1992.
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III. EPA's Analysis of Idaho's Submittal
EPA is proposing to redesignate the West Silver Valley to
attainment for the 2012 annual PM<INF>2.5</INF> NAAQS and to approve
Idaho's related maintenance plan. EPA's proposed approval of the
redesignation request and maintenance plan is based upon EPA's
determination that the area continues to attain the 2012 annual
PM<INF>2.5</INF> NAAQS and that all other redesignation criteria have
been met for the area. The following is a description of how Idaho's
June 2, 2020, submission satisfies the requirements of section
107(d)(3)(E) of the CAA for the 2012 annual PM<INF>2.5</INF> standard.
A. Attainment Determination
To redesignate an area from nonattainment to attainment, the CAA
requires EPA to determine that the area has attained the applicable
NAAQS (CAA section 107(d)(3)(E)(i)). An area is attaining the 2012
annual PM<INF>2.5</INF> NAAQS if it meets the standard, as determined
in accordance with 40 CFR 50.13 and appendix N of 40 CFR part 50. To
attain the 2012 annual PM<INF>2.5</INF> NAAQS, the 3-year average of
the annual arithmetic mean concentration, as determined in accordance
with 40 CFR part 50, appendix N, must be less than or equal to 12.0 mg/
m\3\ at all relevant monitoring sites in the subject area over a 3-year
period. The relevant data must be collected and quality-assured in
accordance with 40 CFR part 58 and recorded in EPA's Air Quality System
(AQS) database.
There is one PM<INF>2.5</INF> ambient air quality monitor in the
West Silver Valley, located in Pinehurst, Idaho (AQS ID 160790017). As
noted, EPA first determined that the West Silver Valley attained the
2012 annual PM<INF>2.5</INF> NAAQS based on 2015-2017 ambient air
quality monitoring data at this monitor on December 21, 2018. 83 FR
65535.
EPA has reviewed the certified, quality-controlled and quality-
assured PM<INF>2.5</INF> Pinehurst monitoring data for the 2018-2020
design value period and determined that the design value is 10.9 mg/
m\3\, which is less than or equal to 12.0 mg/m\3\, and therefore the
area continues to meet the 2012 annual PM<INF>2.5</INF> NAAQS. On this
basis, EPA is proposing to determine that the West Silver Valley is
attaining the 2012 annual PM<INF>2.5</INF> NAAQS. The monitoring data
is summarized in Tables 1 and 2 is also available in the docket for
this action available online at <a href="https://www.regulations.gov">https://www.regulations.gov</a>, Docket ID:
EPA-R10-OAR-2020-0305.
Table 1--2015 to 2020 PM2.5 Annual Means in the West Silver Valley in Idaho
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Annual means in [mu]g/m\3\
Area/county Monitor AQS ID -----------------------------------------------------
2015 2016 2017 * 2018 2019 2020
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Pinehurst/Shoshone........................ 160790017 13.6 9.3 12.3 12.8 9.63 11.1
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* EPA excluded five 24-hr PM2.5 values during September 2017 because those NAAQS exceedances were caused by a
wildfire exceptional event. (See 83 FR 65535, December 21, 2018).
Table 2--2015 to 2020 PM2.5 Annual Design Values in the West Silver Valley in Idaho
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Annual design values in [mu]g/m\3\
Area/county Monitor AQS ID ---------------------------------------------------------------
2015-2017 * 2016-2018 * 2017-2019 * 2018-2020
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Pinehurst/Shoshone.............. 160790017 11.7 11.2 11.3 10.9
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* EPA excluded five 24-hr PM2.5 values during September 2017 because those NAAQS exceedances were caused by a
wildfire exceptional event. (See 83 FR 65535, December 21, 2018).
B. Applicable Requirements Under Section 110 and Part D of the CAA
In accordance with section 107(d)(3)(E)(v) of the CAA, Idaho must
meet all the requirements applicable to the West Silver Valley under
section 110 of the CAA (general SIP requirements) and part D of title I
of the CAA (SIP requirements for nonattainment areas). Under section
107(d)(3)(E)(ii) of the CAA, Idaho's SIP revisions for the 2012 annual
PM<INF>2.5</INF> NAAQS for the West Silver Valley must be fully
approved under section 110(k) of the CAA. Section 110(k) of the CAA
sets out the requirements for EPA's actions on SIP revision submittals.
The September 4, 1992 Calcagni memorandum describes EPA's
interpretation of section 107(d)(3)(E) with respect to the timing of
applicable requirements. Under this interpretation, to qualify for
redesignation, states requesting redesignation to attainment must meet
only the relevant CAA requirements that come due prior to the
[[Page 51320]]
submittal of a complete redesignation request. See also Shapiro
memorandum, September 17, 1993,\2\ and 60 FR 12459, 12465-12466, (March
7, 1995) (redesignation of Detroit-Ann Arbor). Applicable requirements
of the CAA that come due subsequent to the area's submittal of a
complete redesignation request remain applicable until a redesignation
is approved but are not required as a prerequisite to redesignation.
See CAA section 175A(c). Sierra Club v. EPA, 375 F .3d 537 (7th Cir.
2004). See also 68 FR 25418, 25424 and 25427 (May 12, 2003)
(redesignation of the St. Louis/East St. Louis area to attainment of
the 1-hour ozone NAAQS).
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\2\ ``State Implementation Plan (SIP) Requirements for Areas
Submitting Requests for Redesignation to Attainment of the Ozone and
Carbon Monoxide (CO) National Ambient Air Quality Standards (NAAQS)
on or after November 15, 1992,'' Memorandum from Michael H. Shapiro,
Acting Assistant Administrator, Air and Radiation, September
17,1993.
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In the case of the West Silver Valley, the base year emissions
inventory was due prior to Idaho's submittal of the complete
redesignation request for the area. Therefore, the base year inventory
is an applicable requirement. The attainment plan, including RACM/RACT,
and contingency measures for failure to attain or meet RFP, were also
due prior to Idaho's submittal of complete redesignation requests for
the West Silver Valley. However, as described in detail later in this
notice of proposed rulemaking (NPRM), the clean data determination
suspended these requirements for as long as the West Silver Valley
continues to meet the 2012 annual PM<INF>2.5</INF> NAAQS. When the area
is redesignated to attainment, these requirements are permanently
discharged.
1. CAA Section 110 General SIP Requirements
Section 110(a)(2) of title I of the CAA delineates the general
requirements for a SIP, which include enforceable emissions limitations
and other control measures, means, or techniques, provisions for the
establishment and operation of appropriate devices necessary to collect
data on ambient air quality, and programs to enforce the limitations.
The general SIP elements and requirements set forth in section
110(a)(2) of the CAA include, but are not limited to the following: (1)
Submittal of a SIP that has been adopted by the state after reasonable
public notice and hearing; (2) provisions for establishment and
operation of appropriate procedures needed to monitor ambient air
quality; (3) implementation of a minor source permit program; (4)
provisions for the implementation of part C requirements (referred to
as prevention of significant deterioration or PSD); (5) provisions for
the implementation of part D requirements for nonattainment new source
review (referred to as part D NNSR, NNSR, nonattainment NSR, or NSR)
permit programs; (6) provisions for air pollution modeling; and (7)
provisions for public and local agency participation in planning and
emission control rule development.
CAA section 110(a)(2)(D) requires that SIPs contain certain
measures to prevent sources in a state from significantly contributing
to air quality problems in another state. However, CAA section
110(a)(2)(D) requirements for a state are not linked with a particular
nonattainment area's designation and classification in that state. EPA
believes that the requirements linked with a particular nonattainment
area's designation and classifications are the relevant measures to
evaluate in reviewing a redesignation request. The transport SIP
submittal requirements, where applicable, continue to apply to a state
regardless of the designation of any one particular area in the state.
Thus, EPA does not believe that these requirements are applicable
requirements for purposes of redesignation.
In addition, EPA believes that the other CAA section 110(a)(2)
elements not connected with nonattainment plan submissions and not
linked with an area's attainment status are not applicable requirements
for purposes of redesignation because the area will still be subject to
these requirements after it is redesignated. EPA concludes that the CAA
section 110(a)(2) and part D requirements, which are linked with a
particular area's designation and classification, are the relevant
measures to evaluate in reviewing a redesignation request, and that CAA
section 110(a)(2) elements not linked to the area's nonattainment
status are not applicable for purposes of redesignation. This approach
is consistent with EPA's existing policy on applicability of conformity
(i.e., for redesignations) and oxygenated fuels requirement. See
Reading, Pennsylvania, proposed rulemaking and final rule (61 FR 53174,
October 10, 1996), (62 FR 24826, May 7, 1997); Cleveland-Akron-Lorain,
Ohio final rule (61 FR 20458, May 7, 1996); and Tampa, Florida, final
rule (60 FR 62748, December 7, 1995). See also, the discussion on this
issue in the Cincinnati, Ohio redesignation (65 FR at 37890, June 19,
2000), and in the Pittsburgh-Beaver Valley, Pennsylvania redesignation
(66 FR at 53099, October 19, 2001).
EPA has reviewed the Idaho SIP and has concluded that it meets the
general SIP requirements under section 110(a)(2) of the CAA to the
extent they are applicable for the purposes of redesignation. EPA has
previously approved provisions of Idaho's SIP as demonstrating
compliance with the CAA section 110(a)(2) requirements for the 2012
annual PM<INF>2.5</INF> NAAQS (82 FR 57132, December 4, 2017 and 83 FR
48240, September 24, 2018). However, as noted above, the requirements
of section 110(a)(2) are statewide requirements that are not linked to
the PM<INF>2.5</INF> nonattainment status of the West Silver Valley
area. Therefore, EPA believes that these SIP elements are not
applicable requirements for purposes of review of this proposed
redesignation.
Because PSD requirements will apply after redesignation, areas
being redesignated must have an approved PSD program. Once the West
Silver Valley is redesignated to attainment, Idaho's PSD program, and
not NNSR, will become effective in the area. Idaho's PSD regulations
are codified in the Idaho Administrative Procedures Act (IDAPA) at
58.01.01.200-228. We most recently approved revisions to Idaho's PSD
program on August 20, 2018 (83 FR 42033), May 12, 2017 (82 FR 22083)
and August 12, 2016 (81 FR 53290).
Areas seeking redesignation need not comply with the requirement
that a NNSR program be approved prior to redesignation, provided that
the area demonstrates maintenance of the NAAQS without NNSR. A more
detailed rationale for this is described in the Nichols memorandum.
Nevertheless, on August 20, 2018, EPA approved Idaho's SIP as meeting
applicable NNSR requirements. (83 FR 42033). EPA has reviewed the Idaho
SIP and has concluded that it meets the general SIP requirements under
section 110(a)(2) of the CAA to the extent they are applicable for
purposes of redesignation, namely a SIP-approved PSD program.
2. Part D of Title I Requirements
Part D of Title I of the CAA sets forth the basic nonattainment
plan requirements applicable to all nonattainment areas at subpart 1
(CAA sections 172-176) and requirements specific to PM<INF>10</INF> and
PM<INF>2.5</INF> areas at subpart 4 (CAA section 189). On August 24,
2016, EPA promulgated the Fine Particulate Matter National Ambient Air
Quality Standards; State Implementation Plan Requirements
[[Page 51321]]
rule.\3\ This rule implements the requirements of part D of title I of
the CAA for areas designated nonattainment for any PM<INF>2.5</INF>
NAAQS.
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\3\ 81 FR 58010, August 24, 2016. Codified at 40 CFR part 51,
subpart Z.
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EPA's longstanding interpretation of the nonattainment planning
requirements of CAA section 172 is that once an area is attaining the
NAAQS, those requirements are not ``applicable'' for purposes of CAA
section 107(d)(3)(E)(ii) and therefore need not be approved into the
SIP before EPA can redesignate the area. In the 1992 General Preamble
for Implementation of CAA title I, EPA set forth its interpretation of
applicable requirements for purposes of evaluating redesignation
requests when an area is attaining a standard. See 57 FR 13498, 13564
(April 16, 1992). EPA noted that the requirements for RFP and other
measures designed to provide for attainment do not apply in evaluating
redesignation requests because those nonattainment planning
requirements ``have no meaning'' for an area that has already attained
the standard. Id. This interpretation was also set forth in the
Calcagni memorandum. EPA's understanding of CAA section 172 also forms
the basis of its Clean Data Policy, which was articulated with regard
to PM<INF>2.5</INF> in 40 CFR 51.1015 and suspends a state's obligation
to submit most of the attainment planning requirements that would
otherwise apply, including an attainment demonstration and planning
SIPs to provide for RFP, RACM, and contingency measures under section
172(c)(9).\4\ Courts have upheld EPA's interpretation of CAA section
172(c)(1)'s ``reasonably available'' control measures and control
technology as meaning only those controls that advance attainment,
which precludes the need to require additional measures where an area
is already attaining. NRDC v. EPA, 571 F.3d 1245, 1252 (D.C. Cir.
2009); Sierra Club v. EPA, 294 F.3d 155, 162 (D.C. Cir. 2002); Sierra
Club v. EPA, 314 F.3d 735, 744 (5th Cir. 2002).
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\4\ This regulation was promulgated as part of the 1997
PM<INF>2.5</INF> NAAQS implementation rule that was subsequently
challenged and remanded in NRDC v. EPA, 706 F.3d 428 (D.C. Cir.
2013), as discussed in section III.B of this document. However, the
Clean Data Policy portion of the implementation rule was not at
issue in that case.
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As stated previously, EPA determined that the West Silver Valley
has attained the 2012 annual PM<INF>2.5</INF> NAAQS in a ``clean data
determination.'' 83 FR 65535, December 21, 2018. Furthermore, as shown
in section III.A of this document, the West Silver Valley continues to
attain the 2012 annual PM<INF>2.5</INF> NAAQS. Therefore, because
attainment has been reached in the West Silver Valley, no additional
measures are needed to provide for attainment, and CAA section
172(c)(1) requirements for an attainment demonstration and RACM are no
longer considered to be applicable for purposes of redesignation as
long as the West Silver Valley continues to attain the standard until
redesignation.
The CAA section 172(c)(2) requirement that nonattainment plans
contain provisions promoting reasonable further progress toward
attainment is also not relevant for purposes of redesignation because
EPA has determined that the West Silver Valley has monitored attainment
of the 2012 annual PM<INF>2.5</INF> NAAQS. In addition, because the
West Silver Valley has attained the 2012 annual PM<INF>2.5</INF> NAAQS
and is no longer subject to RFP requirements, the requirement to submit
the section 172(c)(9) contingency measures is not applicable for
purposes of redesignation. CAA section 172(c)(6) requires the SIP to
contain control measures necessary to provide for attainment of the
NAAQS. Because attainment has been reached, no additional measures are
needed to provide for attainment.
Section 172(c)(3) of the CAA requires submission and approval of a
comprehensive, accurate and current inventory of actual emissions. The
requirement under CAA section 172(c)(3) was not suspended by EPA's
clean data determination for the 2012 annual PM<INF>2.5</INF> NAAQS and
is the only remaining requirement under CAA section 172 to be
considered for purposes of redesignation of the West Silver Valley. On
September 29, 2017, Idaho submitted to EPA a 2013 base year emissions
inventory for the West Silver Valley for the 2012 annual
PM<INF>2.5</INF> NAAQS. The 2013 base year inventory covers the general
source categories of point sources, nonroad mobile sources, area
sources, and onroad mobile sources and includes PM<INF>2.5</INF>
emissions and precursors, NO<INF>X</INF>, sulfur dioxide
(SO<INF>2</INF>), VOCs, and ammonia (NH<INF>3</INF>). EPA approved the
2013 base year inventory on September 11, 2018 (83 FR 45830).
CAA section 172(c)(4) requires the identification and
quantification of allowable emissions for major new and modified
sources in an area, and section 172(c)(5) requires source permits for
the construction and operation of new and modified major stationary
sources anywhere in the nonattainment area. As stated previously in
this document, EPA has determined that, since PSD requirements will
apply after redesignation, areas being redesignated need not comply
with the requirement that a NNSR program be approved prior to
redesignation, provided that the area demonstrates maintenance of the
NAAQS without NNSR. A more detailed rationale for this view is
described in the Nichols memorandum. Nevertheless, EPA first approved
the requirements of the part D NSR permit program for Idaho under
subpart 1 on November 26, 2010 (75 FR 72719). Subsequently, on March
20, 2018, Idaho submitted rule revisions to meet additional part D NSR
requirements promulgated by EPA under subpart 4 (81 FR 58010, August
24, 2016). We approved Idaho's submission on August 20, 2018 (83 FR
42033).
Once the West Silver Valley is redesignated to attainment, Idaho's
PSD program, and not NNSR, will become effective in the area. Idaho's
PSD regulations are codified in the Idaho Administrative Procedures Act
(IDAPA) at 58.01.01.200-228 (permit to construct) and governed by IDAPA
58.01.01.205 (permit requirements for new major facilities or major
modifications in attainment or unclassifiable areas). We most recently
approved revisions to Idaho's PSD program on August 20, 2018 (83 FR
42033), May 12, 2017 (82 FR 22083) and August 12, 2016 (81 FR 53290).
EPA finds that Idaho's PSD provisions meet all applicable Federal
requirements for any area designated unclassifiable or attainment.
CAA section 172(c)(7) requires the SIP to meet the applicable
provisions of CAA section 110(a)(2). As noted above, we find that the
Idaho SIP meets the CAA section 110(a)(2) applicable requirements for
purposes of redesignation.
Section 175A of the CAA requires a state seeking redesignation to
attainment to submit a SIP revision to provide for the maintenance of
the NAAQS in the area ``for at least 10 years after the
redesignation.'' In conjunction with its requests to redesignate the
West Silver Valley to attainment, Idaho submitted a plan to provide for
maintenance of the 2012 annual PM<INF>2.5</INF> NAAQS in the West
Silver Valley for at least 10 years after redesignation, through 2031.
Idaho is requesting that EPA approve the submission as meeting the
requirement of section 175A of the CAA. Once approved, the maintenance
plan will ensure that the Idaho SIP meets the requirements of the CAA
regarding maintenance of the 2012 annual PM<INF>2.5</INF> NAAQS for the
West Silver Valley. EPA's analysis of the maintenance plan is provided
in section III.D of this document.
EPA concludes that Idaho has met the requirements of subpart 1 of
part D relevant for redesignation. Specifically,
[[Page 51322]]
pursuant to section 110(k) of the CAA, EPA has approved Idaho's 2013
base year inventory for the West Silver Valley into the Idaho SIP.
C. Improvement in Air Quality Due to Permanent and Enforceable Measures
CAA section 107(d)(3)(E)(iii) of the CAA provides that for an area
to be redesignated to attainment, the Administrator must determine that
the improvement in air quality is due to permanent and enforceable
reductions in emissions resulting from implementation of the applicable
implementation plan, implementation of applicable Federal air pollutant
control regulations, and other permanent and enforceable reductions.
In making this demonstration for the West Silver Valley, Idaho
explained that control measures for the area focused on residential
wood combustion, onroad, and nonroad sources, which contributed to
PM<INF>2.5</INF> formation in the 2013 base year emissions inventory
(2013 was one of the years used to designate the area as
nonattainment). The 2017 attainment year emissions inventory recorded
reductions in directly emitted PM<INF>2.5</INF> and precursors for
those categories (2017 is one of the years used to monitor attainment).
Idaho states that the emissions reductions occurred because of
permanent and enforceable federal reduction programs, public outreach,
and financial incentives.
Residential Wood Heating
Idaho's residential wood combustion control measures for the West
Silver Valley addressed smoke from heating devices, such as fireplaces
and wood stoves. In comparing emissions between the 2013 base year
inventory and the 2017 attainment year inventory for the West Silver
Valley, Idaho showed a 63 percent decrease in PM<INF>2.5</INF>
emissions from residential wood combustion, from 55.38 tons per year
(tpy) in the 2013 base year emissions inventory to 20.45 tpy in the
2017 attainment year emissions inventory. Idaho attributed these
emission reductions primarily to Federal standards for wood heaters and
to the West Silver Valley woodstove changeout program.
Idaho explained that EPA's 2015 Standards of Performance for New
Residential Wood Heaters strengthened emissions limits for residential
wood heaters, making devices significantly cleaner.\5\ The 2015 rule
requires, among other things, that new residential wood heaters be
certified to meet the 2015 emission limits before they may be imported,
sold, or distributed in the U.S. To accelerate the removal of
uncertified wood stoves, Idaho incentivized wood stove replacements in
the West Silver Valley through a wood stove changeout program.
Participants in the changeout program replaced uncertified wood stoves
with EPA-certified devices or gas appliances, and were required to
surrender their uncertified wood stoves, making the emissions
reductions permanent. Between 2013 and 2017, Idaho replaced 65 wood
stoves in the West Silver Valley. Although Idaho's future year
emissions projections assume residential wood combustion to be constant
for years beyond 2017, Idaho anticipates additional emissions
reductions as phase II of the Standards of Performance for New
Residential Wood Heaters is implemented and as remaining funding for an
additional 140 wood stove replacements in the West Silver Valley is
distributed.
---------------------------------------------------------------------------
\5\ EPA promulgated standards for residential wood heaters on
February 26, 1988 (53 FR 5860). On March 16, 2015, EPA revised the
rule (80 FR 13672). EPA recently revised the rule on April 2, 2020
(85 FR 18448).
---------------------------------------------------------------------------
Mobile Sources
Idaho states that despite increasing vehicle populations and
vehicle miles traveled, emissions from mobile sources in the West
Silver Valley have decreased as a result of Federal motor vehicle
regulations. In comparing the 2013 base year emissions inventory with
the 2017 attainment year emissions, EPA found that onroad emissions
decreased by 2.55 tpy and nonroad emissions decreased by 3.65 tpy.\6\
---------------------------------------------------------------------------
\6\ The 2013 base year EI onroad emissions were 17.30 tpy and
nonroad emissions were 14.7 tpy (see 83 FR 21976, May 11, 2018).
---------------------------------------------------------------------------
Idaho primarily attributes the reduction in onroad emissions to the
Federal Tier 2 (65 FR 6698, February 10, 2000) and Tier 3 (79 FR 23414,
April 28, 2014) vehicle emissions standards and gasoline sulfur control
requirements, and to the Federal rule for heavy-duty engine and vehicle
standards and highway diesel fuel sulfur control requirements (66 FR
5002, January 18, 2001). Idaho explained that the vehicle standards
reduce tailpipe and evaporative emissions, reductions which increase as
vehicle turnover increases over time, and that the gasoline sulfur
standards make emissions control systems more effective for both
existing and new vehicles.
Idaho identified several Federal rules that have been promulgated
to address nonroad mobile emissions sources. On June 29, 2004, EPA
adopted a comprehensive national program to reduce emissions from
nonroad diesel engines (69 FR 38958). The rule phased in tighter
emissions limits for large nonroad diesel engines and requirements for
reducing the sulfur content of nonroad diesel fuel.
Statewide SIP-Approved Rules
Idaho has several SIP-approved rules that apply statewide and
complement the Federal control strategies in the West Silver Valley.
For example, the following rules assist in the control of
PM<INF>2.5</INF> in the West Silver Valley: The rules for the control
of open burning at IDAPA 58.01.01.600 through 624; the requirements to
reasonably control fugitive dust at sections 650 through 652; the
permitting of industrial sources (sections 200, 300 and 400), and the
specific requirements for nonmetallic mineral processing plants at
sections 795 through 799. Additionally, sections 550 through 562
provide authority to limit emissions during degraded air quality
episodes.
Idaho also assessed the potential role that changing meteorological
conditions might have played in improving air quality in the West
Silver Valley. Idaho reviewed temperature and precipitation data as
well as the frequency of wintertime stagnation events. Idaho concluded
that it is unlikely that favorable meteorological conditions played a
significant role in attaining the 2012 annual PM<INF>2.5</INF> NAAQS.
Based on the evaluation of these control measures, EPA proposes to
determine that the improvement in air quality is reasonably
attributable to permanent and enforceable reductions in emissions
resulting from implementation of the applicable Federal air pollutant
control regulations, and other permanent and enforceable emissions
reductions.
D. Fully Approved Maintenance Plan
In conjunction with Idaho's request to redesignate the West Silver
Valley to attainment, Idaho submitted SIP revisions to provide for
maintenance of the 2012 annual PM<INF>2.5</INF> NAAQS through 2031. EPA
is proposing to approve Idaho's maintenance plan for the West Silver
Valley. If this proposed action is finalized, the West Silver Valley
will have an approved maintenance plan.
CAA section 107(d)(3)(E)(iv) requires that, for a nonattainment
area to be redesignated to attainment, EPA must fully approve a
maintenance plan which meets the requirements of CAA section 175A. The
plan must demonstrate continued attainment of the relevant NAAQS in the
area for at least 10 years after our approval of the redesignation.
Eight years after our approval of a redesignation, the State must
submit a
[[Page 51323]]
revised maintenance plan demonstrating attainment for the 10 years
following the initial 10-year period. The maintenance plan must also
contain a contingency plan to ensure prompt correction of any violation
of the NAAQS. The Calcagni Memo provides additional guidance on the
content of a maintenance plan, stating that a maintenance plan should
include the following elements: (1) An attainment emissions inventory;
(2) a maintenance demonstration showing attainment for 10 years
following redesignation; (3) a commitment to maintain the existing
monitoring network; (4) verification of continued attainment; and (5) a
contingency plan to prevent or correct future violations of the NAAQS.
The following paragraphs describe how each of these elements is
addressed in Idaho's maintenance plan.
1. Attainment Inventory
As discussed in the CAA General Preamble (see 57 FR 13498, April
16, 1992) and the Calcagni Memo, PM<INF>2.5</INF> maintenance plans
should include an attainment emission inventory to identify the level
of emissions in the area which is sufficient to maintain the NAAQS. The
attainment inventory should be consistent with EPA's most recent
guidance on emission inventories for nonattainment areas available at
the time and should include the emissions during the time period
associated with the monitoring data showing attainment.
Idaho submitted a maintenance plan for the West Silver Valley that
includes an attainment year inventory for the area for 2017, which is
one of the years in the period during which the West Silver Valley
first monitored attainment of the 2012 annual PM<INF>2.5</INF> NAAQS
(see section III.A of this document). The attainment year inventory
includes emissions of PM<INF>2.5</INF>, NO<INF>X</INF>, SO<INF>2</INF>,
VOC, and NH<INF>3</INF>. The 2017 attainment levels of emissions are
summarized in Table 3, along with future year projected emissions for
2026 and 2031.
Table 3--West Silver Valley Maintenance Plan Emissions Inventories
[In tons per year]
----------------------------------------------------------------------------------------------------------------
2017 2031 Difference from Difference from
Source category attainment 2026 interim maintenance 2026 and 2017 2031 and 2017
----------------------------------------------------------------------------------------------------------------
PM (condensable and filterable)
----------------------------------------------------------------------------------------------------------------
Point....................... 0.642 0.742 0.742 0.10 0.10
Area........................ 259.710 259.070 258.720 -0.64 -0.99
Onroad...................... 14.700 8.760 9.250 -5.94 -5.45
Nonroad..................... 3.590 1.780 1.590 -1.81 -2.00
-----------------------------------------------------------------------------------
Total................... 278.642 270.352 270.302 -8.29 -8.34
----------------------------------------------------------------------------------------------------------------
NO
----------------------------------------------------------------------------------------------------------------
Point....................... 1.610 6.430 9.200 4.82 7.59
Area........................ 51.130 51.500 51.700 0.37 0.57
Onroad...................... 484.160 324.140 338.400 -160.02 -145.76
Nonroad..................... 62.080 29.910 27.260 -32.17 -34.82
-----------------------------------------------------------------------------------
Total................... 598.980 411.980 426.560 -187.00 -172.42
----------------------------------------------------------------------------------------------------------------
SO
----------------------------------------------------------------------------------------------------------------
Point....................... 0.080 0.110 0.130 0.03 0.05
Area........................ 16.170 16.350 16.450 0.18 0.28
Onroad...................... 0.700 0.760 0.900 0.06 0.20
Nonroad..................... 0.100 0.080 0.090 -0.02 -0.01
-----------------------------------------------------------------------------------
Total................... 17.050 17.300 17.570 0.25 0.52
----------------------------------------------------------------------------------------------------------------
VOC
----------------------------------------------------------------------------------------------------------------
Point....................... 5.710 13.820 13.980 8.11 8.27
Area........................ 3,307.970 3,350.320 3,373.840 42.35 65.87
Onroad...................... 134.200 83.670 73.450 -50.53 -60.75
Nonroad..................... 32.050 28.080 28.200 -3.97 -3.85
-----------------------------------------------------------------------------------
Total................... 3,479.930 3,475.890 3,489.470 -4.04 9.54
----------------------------------------------------------------------------------------------------------------
NH
----------------------------------------------------------------------------------------------------------------
Point....................... 0.020 0.160 0.250 0.14 0.23
Area........................ 35.200 35.090 35.030 -0.11 -0.17
Onroad...................... 4.430 4.490 5.300 0.06 0.87
Nonroad..................... 0.110 0.110 0.110 0.00 0.00
-----------------------------------------------------------------------------------
Total................... 39.760 39.850 40.690 0.09 0.93
----------------------------------------------------------------------------------------------------------------
[[Page 51324]]
Based our review of the emissions inventories Idaho provided in its
submission, we propose to find that Idaho prepared an adequate
attainment inventory for the West Silver Valley area.\7\
---------------------------------------------------------------------------
\7\ ``Emissions Inventory Guidance for Implementation of Ozone
and Particulate Matter National Ambient Air Quality Standards
(NAAQS) and Regional Haze Regulations,'' May 2017.
---------------------------------------------------------------------------
2. Maintenance Demonstration
CAA section 175A requires a state seeking redesignation to
attainment to submit a SIP revision to provide for the maintenance of
the NAAQS in the area ``for at least 10 years after the
redesignation.'' A state can make this demonstration by either showing
that future emissions of a pollutant or its precursors will not exceed
the level of the attainment inventory, or by modeling to show that the
future mix of sources and emissions rates will not cause a violation of
the NAAQS.\8\ In its maintenance plan, Idaho demonstrates maintenance
by showing that emissions projected over the maintenance period will
not exceed emissions levels that were present when the area came into
attainment of the 2012 annual PM<INF>2.5</INF> NAAQS. In its
maintenance demonstration for the West Silver Valley, Idaho projected
emissions forward to 2026 and 2031, which satisfies the 10-year
interval required in section 175A of the CAA. As discussed previously,
Idaho selected 2017 as the attainment emissions inventory year for the
West Silver Valley. The attainment inventory identifies the level of
emissions that is sufficient to attain the 2012 annual PM<INF>2.5</INF>
NAAQS. Idaho has previously submitted a 2013 base year inventory, which
EPA approved into the Idaho SIP on September 11, 2018 (83 FR 45830).
---------------------------------------------------------------------------
\8\ See Calcagni Memo, pages 9-10.
---------------------------------------------------------------------------
The emissions inventories in the West Silver Valley maintenance
plan address four major source categories: Point, area, onroad mobile
and nonroad mobile. Idaho estimated future year emissions inventories
using the latest socioeconomic growth indicators and applying emissions
reduction benefits from adopted control strategies when appropriate.
Idaho identified five minor point sources in the West Silver Valley
and projected emissions to future years by using either their potential
to emit as a conservative estimate of growth, the average annual growth
of population, or assumed little or no expected growth based on data
evidence or conversations with facility owners. Area sources in the
West Silver Valley emissions inventory include residential wood
combustion, solvent use, agricultural production, fuel transport,
combustion (residential, commercial, and industrial), unpaved road
dust, industrial processes, outdoor burning, prescribed fire, and waste
disposal, treatment and recovery processes. Idaho estimated future year
emissions based on the average annual growth rate of the appropriate
activity sector in the previous 5 years through to the final year of
the maintenance plan, 2031. Idaho developed the mobile source inventory
for Shoshone County using the latest version of EPA's Motor Vehicle
Emissions Simulator (MOVES) model at the time,\9\ MOVES2014b, and
apportioned it to the West Silver Valley nonattainment area. Idaho used
local inputs and applied growth rates to the 2017 vehicle miles
travelled and vehicle populations to develop inputs for the 2026 and
2031 projections. Idaho calculated paved road dust emissions according
to AP-42 guidance for Shoshone County and apportioned the emissions
estimates to the West Silver Valley area. To estimate nonroad mobile
source emissions, Idaho used the nonroad component of the MOVES model
and used the model defaults, except for meteorological data.
---------------------------------------------------------------------------
\9\ MOVES 2014b was the latest model version when Idaho
submitted the West Silver Valley redesignation request and
maintenance plan to EPA on June 2, 2020. Since that time, EPA
published model version MOVES3 on January 7, 2021, making it the
latest version of the MOVES model as of this publication. 86 FR
1106. As explained in the notice of availability for MOVES3, state
and local agencies should use the latest version of MOVES that is
available at the time that a SIP is developed. However, state and
local agencies that have already completed significant work on a SIP
with a version of MOVES2014 may continue to rely on the earlier
version of MOVES. Because Idaho submitted the SIP to EPA before
MOVES3 was released, it was appropriate for Idaho to have used
MOVES2014b.
---------------------------------------------------------------------------
EPA has reviewed the documentation provided by Idaho for developing
the 2026 and 2031 emissions inventories for the West Silver Valley and
finds that Idaho prepared them in accordance with EPA requirements.
These inventories indicate a decrease in emissions of PM<INF>2.5</INF>
(38.34 tpy or 3%) and NO<INF>X</INF> (172.42 tpy or 28.79%) throughout
the maintenance period, between 2017 and 2031. Although there are
slight increases in emissions of SO<INF>2</INF> (0.52 tpy or 3.05%),
VOC (9.54 tpy or 0.28%) and NH<INF>3</INF> (0.93 tpy or 2.34%) between
2017 and 2031, which Idaho attributes to population growth, Idaho
demonstrated that this increase will not prevent maintenance of the
NAAQS through 2031.
3. Monitoring Network
In the maintenance plan, Idaho committed to continue to operate the
air monitoring network in accordance with 40 CFR part 58. Idaho stated
that it will work with EPA each year through the air monitoring network
review process to determine the adequacy of the monitoring network, if
additional monitoring is needed, and if or when the site can be
discontinued or relocated.\10\ EPA proposes to determine that the
maintenance plan contains adequate provisions for continued operation
of an air quality monitoring network to verify maintenance of the 2012
annual PM<INF>2.5</INF> NAAQS.
---------------------------------------------------------------------------
\10\ See EPA's November 9, 2020 approval of Idaho's 2020 Annual
Monitoring Network Plan, included in the docket for this action.
---------------------------------------------------------------------------
4. Verification of Continued Attainment
Idaho remains obligated to continue to quality-assure monitoring
data and enter all data into AQS in accordance with Federal guidelines.
Idaho will use air monitoring results to verify continued attainment of
the 2012 annual PM<INF>2.5</INF> NAAQS and to track progress of the
maintenance plan. Idaho is also required to periodically update the
emissions inventory for Shoshone County in accordance with the Annual
Air Emissions Reporting Requirements Rule (AERR). This includes
developing annual inventories for major point sources and a
comprehensive periodic inventory covering all source categories every 3
years.
5. Contingency Plan
CAA section 175A(d) requires that a maintenance plan also include
contingency provisions, as necessary, to promptly correct any violation
of the NAAQS that occurs after redesignation of the area to attainment.
For the purposes of CAA section 175A, a state is not required to have
fully adopted contingency measures that will take effect without
further action by the state in order for the maintenance plan to be
approved. However, the contingency plan is an enforceable part of the
SIP and should ensure that contingency measures are adopted promptly
once they are triggered. The maintenance plan should discuss the
measures to be adopted and a schedule and procedure for adoption and
implementation. The contingency plan must require that the state will
implement all measures contained in the Part D nonattainment plan for
the area prior to redesignation. The state should also identify the
specific indicators, or triggers, which will be used to determine when
the contingency plan will be implemented.
The West Silver Valley maintenance plan identifies actions Idaho
will promptly take to prevent or correct a violation of the 2012 annual
PM<INF>2.5</INF>
[[Page 51325]]
NAAQS. If the annual average PM<INF>2.5</INF> concentration reaches
12.5 ug/m\3\ or greater in a single calendar year, Idaho will evaluate
all appropriate data to determine the cause of the elevated levels and
whether the elevated PM<INF>2.5</INF> levels are likely to continue.
Idaho will evaluate all appropriate data including air quality data,
meteorology, evaluation of wood smoke programs and information on
wildfires or winter power outages to determine the cause of the
exceedance within 6 months of the year in which the annual average
reaches 12.5 ug/m\3\ or greater. If the evaluation indicates that
additional control measures are necessary, Idaho will implement
appropriate contingency measures as expeditiously as possible, no later
than 18 months from the determination of a single year exceedance based
on quality-assured data. If Idaho determines that an exceptional event
contributes to a violation of the 2012 annual PM<INF>2.5</INF>
standard, it will follow EPA's exceptional events rule.\11\
---------------------------------------------------------------------------
\11\ Treatment of Data Influenced by Exceptional Events, October
3, 2016, 81 FR 68216.
---------------------------------------------------------------------------
Idaho has identified the following potential contingency measures
for the West Silver Valley maintenance plan:
<bullet> Increase efforts to control mud and dirt track out from
industrial, construction, and agricultural operations onto paved roads.
<bullet> Adopt local ordinance addressing nonresidential slash
burning to require burn permits year-round.
<bullet> Adopt local ordinances that reduce the residential open
burning days.
<bullet> Adopt a local ordinance that prohibits installing
uncertified wood stoves in residential and commercial buildings.
<bullet> Expand educational efforts to reduce PM<INF>2.5</INF> from
wood smoke.
<bullet> Pursue funds to continue offering wood stove changeouts
and fireplace conversions within the West Silver Valley nonattainment
area.
Based on our analysis of Idaho's submittal, we propose to find that
the contingency measure provisions provided in the West Silver Valley
maintenance plan are sufficient and meet the requirements of CAA
section 175A(d).
E. Requirements for Transportation Conformity and Motor Vehicle
Emissions Budgets (MVEBs)
Transportation conformity is required by CAA section 176(c). 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 or not
they conform to the SIP. Conforming to a SIP means that onroad
transportation activities will not produce new air quality violations,
worsen existing violations, or delay timely attainment of the NAAQS.
Thus, EPA's transportation conformity rule requires a demonstration
that emissions from a metropolitan planning organization's regional
transportation plan and transportation improvement program, involving
Federal Highway Administration (FHWA) or Federal Transit Administration
(FTA) funding or approval, are consistent with the motor vehicle
emissions budgets (MVEBs) contained in a control strategy SIP revision
or maintenance plan (40 CFR 93.101, 93.118, and 93.124). The MVEB is
the level of mobile source emissions of a pollutant relied upon in the
attainment or maintenance demonstration to attain or maintain
compliance with the NAAQS in the nonattainment or maintenance area. A
PM<INF>2.5</INF> maintenance plan should identify MVEBs for direct
PM<INF>2.5</INF>, NO<INF>X</INF> and all other PM<INF>2.5</INF>
precursors from onroad mobile source emissions that are determined to
significantly contribute to PM<INF>2.5</INF> levels in the area.\12\
---------------------------------------------------------------------------
\12\ See 40 CFR 93.102(b)(2)(iv) and (v), and (b)(3).
---------------------------------------------------------------------------
Idaho indicated that the West Silver Valley nonattainment area
meets the definition of an ``isolated rural nonattainment area'' at 40
CFR 93.109(g) because the area does not contain, and is not part of, a
metropolitan planning organization. Neither a transportation
improvement plan nor a regional transportation plan was developed for
the West Silver Valley. Instead, transportation projects for the West
Silver Valley are included in a statewide transportation improvement
plan. The Idaho Transportation Department is responsible for
transportation conformity determinations in this isolated rural
nonattainment area.
The maintenance plan submitted by Idaho for the West Silver Valley
identifies MVEBs for PM<INF>2.5</INF>, NO<INF>X</INF> and VOCs, which
are displayed in Table 4. To determine which precursor pollutants were
required to be included in the MVEB, Idaho reviewed PM<INF>2.5</INF>
speciation at the Pinehurst monitor (AQS ID 160790017). Idaho did not
include emissions from paved road dust because those emissions were
found to be insignificant. Idaho also found that vehicle emissions of
SO<INF>2</INF> and NH<INF>3</INF> contributed minimally to
PM<INF>2.5</INF> in the area and did not include MVEBs for these
precursors in accordance with 40 CFR 93.102(b)(2)(v).
Table 4--2017 and 2031 MVEBs for the West Silver Valley
------------------------------------------------------------------------
Motor vehicle emissions budget (tpy)
Year --------------------------------------
PM2.5 NOX VOC
------------------------------------------------------------------------
2017............................. 10.84 484.16 134.20
2031............................. 3.76 338.14 73.45
------------------------------------------------------------------------
EPA is proposing to find that Idaho has evaluated the appropriate
pollutants and precursors and appropriately established MVEBs for
PM<INF>2.5</INF>, NO<INF>X</INF> and VOCs. Idaho used the most up-to-
date model (MOVES2014b) available at the time of submission in order to
appropriately calculate these budgets. The MVEBs are based on the
control measures in the maintenance plan and consistent with
maintaining the 2012 annual PM<INF>2.5</INF> NAAQS.
IV. Proposed Action
EPA is proposing to redesignate the West Silver Valley 2012 annual
PM<INF>2.5</INF> nonattainment area, and to approve the associated
maintenance plan for the area. If this proposal is finalized, the
designation status of the West Silver Valley under 40 CFR part 81 will
be revised to attainment upon the effective date of the final action.
V. Statutory and Executive Order Reviews
Under the CAA, redesignation of an area to attainment and the
accompanying approval of a maintenance plan under section
[[Page 51326]]
107(d)(3)(E) are actions that affect the status of a geographical area
and do not impose any additional regulatory requirements on sources
beyond those imposed by state law. A redesignation to attainment does
not in and of itself create any new requirements, but rather results in
the applicability of requirements contained in the CAA for areas that
have been redesignated to attainment. Moreover, the Administrator is
required to approve a SIP submission that complies with the provisions
of the CAA and applicable Federal regulations. 42 U.S.C. 7410(k); 40
CFR 52.02(a). Thus, in reviewing SIP submissions, EPA's role is to
approve state choices, provided that they meet the criteria of the CAA.
Accordingly, this action merely approves state law as meeting Federal
requirements and does not impose additional requirements beyond those
already imposed by state law. For that reason, this 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).
In addition, this proposed action does not 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, this rulemaking does not have tribal implications as specified
by Executive Order 13175 (65 FR 67249, November 9, 2000), because
redesignation is an action that affects the status of a geographical
area and does not impose any new regulatory requirements on tribes,
impact any existing sources of air pollution on tribal lands, nor
impair the maintenance of ozone national ambient air quality standards
in tribal lands.
List of Subjects
40 CFR Part 52
Environmental protection, Air pollution control, Incorporation by
reference, Intergovernmental relations, Lead, Nitrogen dioxide, Ozone,
Particulate matter, Reporting and recordkeeping requirements, Sulfur
oxides, Volatile organic compounds.
40 CFR Part 81
Environmental protection, Air pollution control, National parks,
Wilderness areas.
Authority: 42 U.S.C. 7401 et seq.
Dated: September 8, 2021.
Michelle L. Pirzadeh,
Acting Regional Administrator, Region 10.
[FR Doc. 2021-19801 Filed 9-14-21; 8:45 am]
BILLING CODE 6560-50-P
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</html>Indexed from Federal Register on September 15, 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.