[Federal Register Volume 86, Number 54 (Tuesday, March 23, 2021)]
[Proposed Rules]
[Pages 15436-15439]
[FR Doc No: 2021-05600]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2019-0597; Project Identifier 2019-NE-05-AD]
RIN 2120-AA64

Airworthiness Directives; CFM International, S.A. Turbofan
Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Supplemental notice of proposed rulemaking (SNPRM).

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SUMMARY: The FAA is revising a notice of proposed rulemaking (NPRM)
that applied to certain CFM International, S.A. (CFM) CFM56-5B, CFM56-
5C, and CFM56-7B model turbofan engines with a certain rotating air
high-pressure turbine (HPT) front seal. This action revises the NPRM by
requiring CFM56-5B or CFM56-7B model turbofan engines with an installed
reconfigured rotating air HPT front seal, which was previously
installed and operated in a CFM56-5C model turbofan engine, to follow
the removal requirements for the CFM56-5C model turbofan engine. The
FAA is proposing this airworthiness directive (AD) to address the
unsafe condition on these products. Since these actions would impose an
additional burden over those in the NPRM the agency is requesting
comments on this SNPRM.

DATES: The FAA must receive comments on this SNPRM by May 7, 2021.

ADDRESSES: You may send comments, using the procedures found in 14 CFR
11.43 and 11.45, by any of the following methods:
     Federal eRulemaking Portal: Go to https://www.regulations.gov. Follow the instructions for submitting comments.
     Fax:<PHONE_NUMBER>.
     Mail: U.S. Department of Transportation, Docket
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New
Jersey Avenue SE, Washington, DC 20590.
     Hand Delivery: Deliver to Mail address above between 9
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    For service information identified in this SNPRM, contact CFM
International, S.A., Aviation Operations Center, 1 Neumann Way, M/D
Room 285, Cincinnati, OH 45125; phone:<PHONE_NUMBER>; email:
<EMAIL_ADDRESS>You may view this service information at
the FAA, Airworthiness Products Section, Operational Safety Branch,
1200 District Avenue, Burlington, MA 01803. For information on the
availability of this material at the FAA, call<PHONE_NUMBER>.

Examining the AD Docket

    You may examine the AD docket at https://www.regulations.gov by
searching for and locating Docket No. FAA-2019-0597; or in person at
Docket Operations between 9 a.m. and 5 p.m., Monday through Friday,
except Federal holidays. The AD docket contains the NPRM, this SNPRM,
any comments received, and other information. The street address for
Docket Operations is listed above.

FOR FURTHER INFORMATION CONTACT: Christopher McGuire, Aviation Safety
Engineer, ECO Branch, FAA, 1200 District Avenue, Burlington, MA 01803;
phone:<PHONE_NUMBER>; fax:<PHONE_NUMBER>; email:
<EMAIL_ADDRESS>
SUPPLEMENTARY INFORMATION:

Comments Invited

    The FAA invites you to send any written relevant data, views, or
arguments about this proposal. Send your comments to an address listed
under ADDRESSES. Include ``Docket No. FAA-2019-0597; Project Identifier
2019-NE-05-AD'' at the beginning of your comments. The most helpful
comments reference a specific portion of the proposal, explain the
reason for any recommended change, and include supporting data. The FAA
will consider all comments received by the closing date and may again
revise this proposal because of those comments.
    Except for Confidential Business Information (CBI) as described in
the following paragraph, and other information as described in 14 CFR
11.35, the FAA will post all comments received, without change, to
https://www.regulations.gov, including any personal information you
provide. The agency will also post a report summarizing each
substantive verbal contact received about this proposed AD.

Confidential Business Information

    CBI is commercial or financial information that is both customarily
and actually treated as private by its owner. Under the Freedom of
Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public
disclosure. If your comments responsive to this SNPRM contain
commercial or financial information that is customarily treated as
private, that you actually treat as private, and that is relevant or
responsive to this SNPRM, it is important that you clearly designate
the submitted comments as CBI. Please mark each page of your submission
containing CBI as ``PROPIN.'' The FAA will treat such marked
submissions as confidential under the FOIA, and they will not be placed
in the public docket of this SNPRM. Submissions containing CBI should
be sent to Christopher McGuire, Aviation Safety Engineer, ECO Branch,
FAA, 1200 District Avenue, Burlington, MA 01803. Any commentary that
the FAA receives which is not specifically designated as CBI will be
placed in the public docket for this rulemaking.

Background

    The FAA issued an NPRM to amend 14 CFR part 39 to supersede AD
2019-12-05, Amendment 39-19660 (84 FR 28717, June 20, 2019), (AD 2019-
12-05). AD 2019-12-05 applies to all CFM CFM56-5B, CFM56-5C, and CFM56-
7B model turbofan engines with a certain rotating air HPT front seal.
The NPRM published in the Federal Register on October 23, 2019 (84 FR
56709). The NPRM was prompted by cracks found in the rotating air HPT
front seal. In the NPRM, the FAA proposed to require replacement of the
affected rotating air

HPT front seal with a part eligible for installation.

Actions Since the NPRM Was Issued

    Since the FAA issued the NPRM, CFM has issued CFM Service Bulletin
(SB) CFM56-5B S/B 72-1074, Revision 02, dated November 6, 2019; CFM SB
CFM56-5C S/B 72-0794, Revision 02, dated November 6, 2019; and CFM SB
CFM56-7B S/B 72-1042, Revision 02, dated November 6, 2019. These SBs
provide service information for following the removal limits
established for CFM56-5C model turbofan engines for CFM56-5B or CFM56-
7B model turbofan engines with a reconfigured rotating air HPT front
seal that was previously operated in a CFM56-5C model turbofan engine.

Comments

    The following discussion presents the comments received on the NPRM
and the FAA's response.

Request To Revise and Remove Installation Prohibition

    American Airlines, CFM, and Lufthansa Technik AG requested the FAA
revise the language in the Installation Prohibition to specify that it
is only applicable to those rotating air HPT front seals that have
affected serial numbers (S/Ns). Lufthansa Technik AG also requested the
FAA remove the Installation prohibition from this proposed rule.
Lufthansa Technik AG indicated that this AD already requires the
removal of rotating air HPT front seals at an interval that will
prevent an unsafe condition.
    The FAA partially agrees. The FAA has revised this proposed AD by
adding language to the Installation Prohibition referencing the
specific S/Ns in the Applicability section to ensure that the rotating
air HPT front seals affected by the Installation Prohibition are clear.
The FAA disagrees with the request to remove the Installation
Prohibition. The requirement to remove rotating air HPT front seals is
necessary to address the unsafe condition and provide a drawdown period
to remove the affected rotating air HPT front seals from service.
Rotating air HPT front seals installed on a different HPT disk from
which they were removed after the effective date of the AD will not
meet the certified removal limits established in the Airworthiness
Limitations Section.

Request To Clarify Engine and Rotating Air HPT Front Seal Intermix
Requirements

    American Airlines requested the FAA clarify the engine and rotating
air HPT front seal intermix requirements, since CFM has released SB
revisions that provide guidance on rotating air HPT front seals that
have been operated in multiple engine models.
    The FAA agrees and has revised this proposed AD. The FAA revised
the compliance requirements in this proposed AD by adding additional
required actions for CFM56-5C model turbofan engines with an affected
rotating air HPT front seal that was assembled to a second or later HPT
disk since being reconfigured.

Request To Specify No Reporting Requirement

    American Airlines requested the FAA add a paragraph to this
proposed AD to specify that there are no reporting requirements. The
commenter noted that the CFM SBs specify reporting information to CFM.
    The FAA disagrees. The required actions of this AD do not mandate
the use of the referenced service information to comply with this AD.
The reporting instructions included in the SBs are not required by this
AD. The FAA made no change to this AD.

Request To Clarify Inclusion of Engine Models

    Lufthansa Technik AG requested the FAA provide clarification
regarding the NPRM supersedure preamble's discussion of expanding the
applicability of the AD to include CFM56-5B, CFM56-5C, and CFM56-7B
model turbofan engines. The commenter indicated that those engine
models are already included in applicability of the AD 2019-12-05.
    The NPRM supersedure preamble states that AD 2019-12-05 only
addresses the highest risk engines with an affected rotating air HPT
seal that has a specified number of cycles since being reconfigured.
The NPRM supersedure proposes to expand the affected engine models to
include all CFM CFM56-5B, CFM56-5C, and CFM56-7B model turbofan
engines, including those engines that have fewer cycles since being
reconfigured. The NPRM supersedure does not propose the addition of
affected engine models to the applicability. The FAA made no change to
this proposed AD.

FAA's Determination

    The FAA is proposing this AD after determining the unsafe condition
described previously is likely to exist or develop in other products of
the same type design. Certain changes described above expand the scope
of the NPRM. As a result, it is necessary to reopen the comment period
to provide additional opportunity for the public to comment on this
SNPRM.

Related Service Information

    The FAA reviewed CFM Service Bulletin (SB) CFM56-5B S/B 72-1074,
Revision 02, dated November 6, 2019; CFM SB CFM56-5C S/B 72-0794,
Revision 02, dated November 6, 2019; and CFM SB CFM56-7B S/B 72-1042,
Revision 02, dated November 6, 2019. CFM SB CFM56-5B S/B 72-1074,
Revision 02, describes procedures for replacement of the affected
rotating air HPT front seal on CFM CFM56-5B model turbofan engines. CFM
SB CFM56-5C S/B 72-0794, Revision 02, describes procedures for
replacement of the affected rotating air HPT front seal on CFM CFM56-5C
model turbofan engines. CFM SB CFM56-7B S/B 72-1042, Revision 02,
describes procedures for replacement of the affected rotating air HPT
front seal on CFM CFM56-7B model turbofan engines.

Proposed AD Requirements in This SNPRM

    This proposed AD would retain the requirements of AD 2019-12-05 (84
FR 28717, June 20, 2019) (AD 2019-12-05). The proposed AD would expand
the applicability to require the replacement of affected rotating air
HPT front seals installed on CFM CFM56-5B, CFM56-5C, and CFM56-7B model
turbofan engines that have fewer cycles since being reconfigured than
the engines affected by AD 2019-12-05. This proposed AD would also
require CFM56-5B and CFM56-7B model turbofan engines with a
reconfigured rotating air HPT front seal that was previously operated
in a CFM56-5C model turbofan engine to follow the removal requirements
of the CFM56-5C model turbofan engine.

Costs of Compliance

    The FAA estimates that this AD, if adopted as proposed, would
affect four engines installed on airplanes of U.S. registry.
    The FAA estimates the following costs to comply with this proposed
AD:

                                                 Estimated Costs
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                                                                                Cost per      Cost on U.S.
                Action                         Labor cost           Parts cost        product        operators
----------------------------------------------------------------------------------------------------------------
Replace the rotating air HPT front      1 work-hour x $85 per           $344,600        $344,685      $1,378,740
 seal.                                   hour = $85.
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Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to
issue rules on aviation safety. Subtitle I, section 106, describes the
authority of the FAA Administrator. Subtitle VII: Aviation Programs
describes in more detail the scope of the Agency's authority.
    The FAA is issuing this rulemaking under the authority described in
Subtitle VII, Part A, Subpart III, Section 44701: General requirements.
Under that section, Congress charges the FAA with promoting safe flight
of civil aircraft in air commerce by prescribing regulations for
practices, methods, and procedures the Administrator finds necessary
for safety in air commerce. This regulation is within the scope of that
authority because it addresses an unsafe condition that is likely to
exist or develop on products identified in this rulemaking action.

Regulatory Findings

    The FAA determined that this proposed AD would not have federalism
implications under Executive Order 13132. This proposed AD would not
have a substantial direct effect on the States, on the relationship
between the national government and the States, or on the distribution
of power and responsibilities among the various levels of government.
    For the reasons discussed above, I certify this proposed
regulation:
    (1) Is not a ``significant regulatory action'' under Executive
Order 12866,
    (2) Would not affect intrastate aviation in Alaska, and
    (3) Would not have a significant economic impact, positive or
negative, on a substantial number of small entities under the criteria
of the Regulatory Flexibility Act.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.

The Proposed Amendment

    Accordingly, under the authority delegated to me by the
Administrator, the FAA proposes to amend 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0
1. The authority citation for part 39 continues to read as follows:

    Authority:  49 U.S.C. 106(g), 40113, 44701.

Sec.  39.13  [Amended]

0
2. The FAA amends Sec.  39.13 by removing Airworthiness Directive (AD)
2019-12-05, Amendment 39-19660 (84 FR 28717, June 20, 2019), and adding
the following new AD:

CFM International, S.A.: Docket No. FAA-2019-0597; Project
Identifier 2019-NE-05-AD.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive
(AD) by May 7, 2021.

(b) Affected ADs

    This AD replaces AD 2019-12-05, Amendment 39-19660 (84 FR 28717,
June 20, 2019).

(c) Applicability

    This AD applies to:
    (1) CFM International, S.A. (CFM) CFM56-5B1, -5B2, -5B4, -5B5, -
5B6, -5B7, -5B1/P, -5B2/P, -5B3/P, -5B4/P, -5B5/P, -5B6/P, -5B7/P, -
5B8/P, -5B9/P, -5B3/P1, -5B4/P1, -5B1/2P, -5B2/2P, -5B3/2P, -5B4/2P,
-5B6/2P, -5B9/2P, -5B3/2P1, -5B4/2P1, -7B20, -7B22, -7B24, -7B26, -
7B27, -7B22/B1, -7B24/B1, -7B26/B1, -7B26/B2, -7B27/B1, -7B27/B3, -
7B20/2, -7B22/2, -7B24/2, -7B26/2, -7B27/2, -7B27A model turbofan
engines with a:
    (i) Rotating air high-pressure turbine (HPT) front seal:
    (A) With part number (P/N) 1795M36P01 or P/N 1795M36P02 and
serial numbers (S/Ns) GWNDN949 through GWNSE969 or S/Ns GWN000CE
through GWN0990L, not including S/Ns GWN08ND7, GWN0923A, GWN0971E,
GWN098A1, GWN098W6, GWN098W8, GWN098WA, and GWN0990G, installed, and
    (B) That has been removed from the original HPT disk and re-
assembled to a different HPT disk.
    (ii) [Reserved]
    (2) CFM CFM56-5C2, -5C2/4, -5C2/F, -5C2/F4, -5C2/G, -5C2/G4, -
5C2/P, -5C3/F, -5C3/F4, -5C3/G, -5C3/G4, -5C3/P, -5C4, -5C4/1, -5C4/
P, -5C4/1P model turbofan engines with a:
    (i) Rotating air HPT front seal:
    (A) With P/N 1795M36P01 or P/N 1795M36P02 and S/Ns GWNDN949
through GWNSE969 or S/Ns GWN000CE through GWN0990L, not including S/
Ns GWN08ND7, GWN0923A, GWN0971E, GWN098A1, GWN098W6, GWN098W8,
GWN098WA, and GWN0990G, installed, and
    (B) That has been removed from the original HPT disk and re-
assembled to a different HPT disk.
    (ii) [Reserved]

(d) Subject

    Joint Aircraft System Component (JASC) Code 7250, Turbine
Section.

(e) Unsafe Condition

    This AD was prompted by cracks found in the rotating air HPT
front seal. The FAA is issuing this AD to prevent failure of the
rotating air HPT front seal. The unsafe condition, if not addressed,
could result in the uncontained release of the rotating air HPT
front seal, damage to the engine, and damage to the airplane.

(f) Compliance

    Comply with this AD within the compliance times specified,
unless already done.

(g) Required Actions

    (1) For all affected CFM CFM56-5B and CFM56-7B model turbofan
engines:
    (i) If, on July 5, 2019 (the effective date of AD 2019-12-05),
the rotating air HPT front seal has 7,000 cycles or greater since
being reconfigured, remove the part from service within 50 cycles
after July 5, 2019 (the effective date of AD 2019-12-05), or before
further flight, whichever occurs later, and replace with a part
eligible for installation.
    (ii) If, on July 5, 2019 (the effective date of 2019-12-05), the
rotating air HPT front seal has between 6,001 and 6,999 cycles,
inclusive, since being reconfigured, remove the part from service
within 500 cycles after July 5, 2019 (the effective date of AD 2019-
12-05), but not to exceed 7,050 cycles since being reconfigured, or
before further flight, whichever occurs later, and replace with a
part eligible for installation.
    (iii) For all remaining CFM56-5B and CFM56-7B model turbofan
engines, remove the rotating air HPT front seal from service before
accumulating 6,500 cycles since being reconfigured, or within 50
cycles after the effective date of this AD, whichever occurs later.
    (2) For all affected CFM CFM56-5C model turbofan engines:
    (i) If, on July 5, 2019 (the effective date of AD 2019-12-05),
the rotating air HPT front seal has 4,250 cycles or greater since
being reconfigured, remove the part from service within 25 cycles
after July 5, 2019 (the effective date of AD 2019-12-05), within
1,500 cycles since the last fluorescent penetrant inspection (FPI)
of the rotating air HPT front seal, or before further flight after
the effective date of this AD, whichever occurs later, and replace
with a part eligible for installation.
    (ii) If, on July 5, 2019 (the effective date of AD 2019-12-05),
the rotating air HPT front

seal has between 3,751 and 4,249 cycles, inclusive, since being
reconfigured, remove the part from service within 250 cycles after
July 5, 2019 (the effective date of AD 2019-12-05), before
accumulating 4,275 cycles since being reconfigured, within 1,500
cycles since the last FPI of the rotating air HPT front seal, or
before further flight after the effective date of this AD, whichever
occurs later, and replace with a part eligible for installation.
    (iii) For all remaining CFM CFM56-5C model turbofan engines,
remove the rotating air HPT front seal from service before
accumulating 4,000 cycles since being reconfigured, or within 50
cycles after the effective date of this AD, whichever occurs later.
    (3) For CFM56-5B or CFM56-7B model turbofan engines with an
affected rotating air HPT front seal that has been operated in a
CFM56-5C model turbofan engine since being reconfigured, remove the
rotating air HPT front seal from service using the cycle limits in
paragraph (g)(2) of this AD.

(h) Definition

    For the purpose of this AD, ``reconfigured'' occurs when a
rotating air HPT front seal has been removed from the original HPT
disk and re-assembled to a different HPT disk.

(i) Installation Prohibition

    After the effective date of this AD, do not assemble any
rotating air HPT front seal with greater than 0 cycles since new,
having a S/N listed in paragraph (c) of this AD onto a HPT disk
unless it is the same S/N HPT disk on which it has previously been
assembled.

(j) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, ECO Branch, FAA, has the authority to approve
AMOCs for this AD, if requested using the procedures found in 14 CFR
39.19. In accordance with 14 CFR 39.19, send your request to your
principal inspector or local Flight Standards District Office, as
appropriate. If sending information directly to the manager of the
certification office, send it to the attention of the person
identified in Related Information. You may email your request to:
<EMAIL_ADDRESS>    (2) Before using any approved AMOC, notify your appropriate
principal inspector, or lacking a principal inspector, the manager
of the local flight standards district office/certificate holding
district office.

(k) Related Information

    (1) For more information about this AD, contact Christopher
McGuire, Aviation Safety Engineer, ECO Branch, FAA, 1200 District
Avenue, Burlington, MA 01803; phone:<PHONE_NUMBER>; fax: (781) 238-
7199; email<EMAIL_ADDRESS>    (2) For service information identified in this AD, contact CFM
International, S.A., Aviation Operations Center, 1 Neumann Way, M/D
Room 285, Cincinnati, OH 45125; phone:<PHONE_NUMBER>; email:
<EMAIL_ADDRESS>You may view this referenced service
information at the FAA, Airworthiness Products Section, Operational
Safety Branch, 1200 District Avenue, Burlington, MA 01803. For
information on the availability of this material at the FAA, call
(781) 238-7759.

    Issued on March 12, 2021.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification
Service.
[FR Doc. 2021-05600 Filed 3-22-21; 8:45 am]
BILLING CODE 4910-13-P


[Federal Register Volume 83, Number 92 (Friday, May 11, 2018)]
[Proposed Rules]
[Pages 21976-21983]
[FR Doc No: 2018-09992]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 52 and 81

[EPA-R10-OAR-2017-0582; FRL-9977-96--Region 10]

Air Plan Approval; ID, Pinehurst PM10 Redesignation, Limited
Maintenance Plan; West Silver Valley 2012 Annual PM2.5 Emission
Inventory

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: On September 29, 2017, the Idaho Department of Environmental
Quality (IDEQ) submitted a redesignation request and limited
maintenance plan (LMP) for particulate matter with an aerodynamic
diameter less than or equal to ten micrometers (PM10) for
the PM10 National Ambient Air Quality Standard (NAAQS)
developed for the Pinehurst PM10 Nonattainment Area (NAA)
and Pinehurst PM10 Expansion Nonattainment Area (NAA). The
redesignation request asserts that the area meets the Clean Air Act
(CAA) requirements for redesignation identified in section
107(d)(3)(E). This limited maintenance plan for these contiguous
nonattainment areas addresses maintenance of the PM10
standard for a ten-year period beyond redesignation. The Environmental
Protection Agency (EPA) proposes to approve this IDEQ Implementation
Plan (SIP) revision. The EPA also proposes to approve the September 15,
2013, high wind exceptional event at the Pinehurst monitoring station.
Additionally, the EPA is proposing to approve the emissions inventory
for the West Silver Valley annual PM2.5 NAA.

DATES: Written comments must be received on or before June 11, 2018.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-R10-
OAR-2017-0582, at http://www.regulations.gov. Follow the online
instructions for submitting comments. Once submitted, comments cannot
be edited or removed from Regulations.gov. The EPA may publish any
comment received to its public docket. Do not submit electronically any
information you consider to be Confidential Business Information (CBI)
or other information whose disclosure is restricted by statute.
Multimedia submissions (audio, video, etc.) must be accompanied by a
written comment. The written comment is considered the official comment
and should include discussion of all points you wish to make. The EPA
will generally not consider comments or comment contents located
outside of the primary submission (i.e., on the web, cloud, or other
file sharing system). For additional submission methods, the full EPA
public comment policy, information about CBI or multimedia submissions,
and general guidance on making effective comments, please visit http://www2.epa.gov/dockets/commenting-epa-dockets.

FOR FURTHER INFORMATION CONTACT: Justin Spenillo, Air Planning Unit,
Office of Air and Waste (OAW-150), Environmental Protection Agency,
Region 10, 1200 Sixth Ave., Suite 900, Seattle, WA 98101; telephone
number:<PHONE_NUMBER>, email address: [email protected].

SUPPLEMENTARY INFORMATION: Throughout this document, wherever ``we'',
``us'' or ``our'' are used, it is intended to refer to the EPA.

Table of Contents

I. This Action
II. Background
    A. PM10 NAAQS
    B. Pinehurst PM10 NAA and Planning Background
III. Requirements for Redesignation
    A. CAA Requirements for Redesignation of Nonattainment Area
    B. The LMP Option for PM10 Nonattainment Areas
    C. Conformity Under the LMP Option
IV. Review of the Idaho Submittal Addressing the Requirements for
Redesignation and LMPs
    A. Has the Pinehurst PM10 NAA attained the applicable
NAAQS?
    B. Does the Pinehurst PM10 NAA have a fully approved
SIP under section 110(k) of the CAA?
    C. Has the IDEQ met all applicable requirements under section
110 and Part D of the CAA?
    D. Has the IDEQ demonstrated that the air quality improvement is
due to permanent and enforceable reductions?
    E. Does the area have a fully approved maintenance plan pursuant
to section 175A of the CAA?
    F. Has the IDEQ demonstrated that the Pinehurst PM10
NAA qualifies for the LMP Option?
    G. Does the IDEQ have an approved attainment emissions inventory
which can be used to demonstrate attainment of the NAAQS?
    H. Does the LMP include an assurance of continued operation of
an appropriate EPA-approved air quality monitoring network, in
accordance with 40 CFR part 58?
    I. Does the plan meet the clean air act requirements for
contingency provisions?
    J. How is conformity treated under a limited maintenance plan?
V. 2013 p.m.10 High Wind Exceptional Event
VI. West Silver Valley 2012 Annual PM2.5 Emission
Inventory

    A. Requirements for Emissions Inventories
    B. West Silver Valley PM2.5 Base Year Emissions
Inventory
    C. EPA's Evaluation
VII. Proposed Action
VIII. Statutory and Executive Order Reviews

I. This Action

    The EPA is proposing to approve the limited maintenance plan (LMP)
submitted by the Idaho Department of Environmental Quality (IDEQ) on
September 29, 2017, for the Pinehurst PM10 Nonattainment
Area (NAA) and Pinehurst PM10 Expansion NAA and to
concurrently redesignate the areas to attainment for the
PM10 National Ambient Air Quality Standard (NAAQS).
Throughout this notice, Pinehurst PM10 NAA shall refer to
both the original Pinehurst PM10 NAA and Pinehurst
PM10 Expansion NAA unless noted otherwise. The EPA has
reviewed air quality data for the area and determined that the
Pinehurst NAA attained the PM10 NAAQS by the required
attainment date, and that monitoring data continue to show attainment.
The EPA is proposing to approve exclusion of data from a high wind
exceptional event on September 15, 2013, that impacted PM10
values at the Pinehurst monitor as they are needed to meet the LMP
criteria. Separately, the EPA is proposing to approve the base year
emission inventory for the West Silver Valley (WSV) PM2.5
NAA in the Silver Valley, Idaho.

II. Background

A. PM10 NAAQS

    ``Particulate matter,'' also known as particle pollution or PM, is
a complex mixture of extremely small particles and liquid droplets. The
size of particles is directly linked to their potential for causing
health problems. The EPA is concerned about particles that are 10
micrometers in diameter or smaller because those are the particles that
generally pass through the throat and nose and enter the lungs. Once
inhaled, these particles can affect the heart and lungs and can cause
serious adverse health effects. People with heart or lung diseases,
children and older adults are the most likely to be affected by
particle pollution exposure. Healthy individuals may also experience
temporary symptoms from exposure to elevated levels of particle
pollution.
    On July 1, 1987, the EPA promulgated a NAAQS for PM10
(52 FR 24634). The EPA established a 24-hour standard of 150 [micro]g/
m\3\ and an annual standard of 50 [micro]g/m\3\, expressed as an annual
arithmetic mean. The EPA also promulgated secondary PM10
standards that were identical to the primary standards. In a rulemaking
action dated October 17, 2006, the EPA retained the 24-hour
PM10 standard but revoked the annual PM10
standard (71 FR 61144, effective December 18, 2006).

B. Pinehurst PM10 NAA and Planning Background

    On July 1, 1987, the EPA promulgated the PM10 NAAQS (52
FR 24634) and on August 7, 1987, the EPA identified the Pinehurst area
as a ``Group I'' area with a strong likelihood of violating the NAAQS
(52 FR 29383). On March 15, 1991, the EPA published a notice announcing
that the Pinehurst area had been designated a PM10 NAA upon
the November 15, 1990 enactment of the 1990 CAA Amendments. In this
notice, the EPA identified that the IDEQ needed to develop and submit
by November 15, 1991, a plan that would bring the area into attainment
by no later than December 31, 1994 (56 FR 11101). On November 6, 1991,
the Pinehurst PM10 NAA, which included the City of
Pinehurst, was classified as moderate under sections 107(d)(4)(B) and
188(a) of the CAA (56 FR 56694), and it had an attainment date of no
later than December 31, 1994. On December 21, 1993, the EPA designated
the Pinehurst PM10 Expansion NAA, a contiguous area to the
south of the City of Pinehurst and the existing Pinehurst
PM10 NAA; the action became effective January 20, 1994 (58
FR 67334). The Pinehurst Expansion area had an attainment date no later
than December 31, 2000. These two nonattainment areas, while contiguous
and share common planning elements, have separate timing requirements
and are considered separate nonattainment areas.
    After these designations to nonattainment for the Pinehurst
PM10 NAA, the IDEQ worked with the community of Pinehurst to
develop a plan to bring the Pinehurst PM10 NAA into
attainment. The IDEQ submitted a plan for the Pinehurst PM10
NAA, both the original and expansion areas, to the EPA on April 14,
1992, as a moderate PM10 State Implementation Plan (SIP)
under section 189(a) of the CAA. The IDEQ's submitted plan addressed
PM10 reductions through a suite of measures aimed at
reducing wood smoke, primarily through a program to replace woodstoves
with cleaner burning devices. The EPA conditionally approved the IDEQ's
moderate PM10 SIP applicable to the City of Pinehurst on
August 25, 1994 (59 FR 43745) and conditionally approved the revisions
applicable to the Pinehurst PM10 Expansion area on May 26,
1995 (60 FR 27891). Both plans were conditionally approved because
these areas had failed to submit contingency measures. The IDEQ
submitted a contingency plan covering both areas on July 13, 1995,
which the EPA subsequently approved on October 2, 2014 (79 FR 59435).
On August 23, 2001, the EPA published a finding that the two areas had
attained the PM10 standard by their respective attainment
dates (66 FR 44304).
    The IDEQ prepared a LMP for the Pinehurst PM10 NAA and
provided notice and an opportunity for public comment on the proposed
plan. On September 29, 2017, the IDEQ submitted the Pinehurst
PM10 LMP to EPA for approval and has requested that the EPA
redesignate the Pinehurst NAA to attainment for the PM10
NAAQS.

III. Requirements for Redesignation

A. CAA Requirements for Redesignation of Nonattainment Area

    A nonattainment area can be redesignated to attainment after the
area has measured air quality data showing the NAAQS has been attained
and when certain planning requirements are met. Section 107(d)(3)(E) of
the CAA, and the General Preamble to Title I provide the criteria for
redesignation (57 FR 13498, April 16, 1992). These criteria are further
clarified in a policy and guidance memorandum from John Calcagni,
Director, Air Quality Management Division, EPA Office of Air Quality
Planning and Standards dated September 4, 1992, entitled ``Procedures
for Processing Requests to Redesignate Areas to Attainment'' (Calcagni
memo). The criteria for redesignation are:
    1. The Administrator has determined that the area has attained the
applicable NAAQS;
    2. The Administrator has fully approved the applicable SIP for the
area under section 110(k) of the CAA;
    3. The state has met all requirements applicable to the area under
section 110 and part D of the CAA;
    4. The Administrator has determined that the improvement in air
quality is due to permanent and enforceable reductions in emissions;
and
    5. The Administrator has fully approved a maintenance plan for the
area as meeting the requirements of section 175A of the CAA.

B. The LMP Option for PM10 Nonattainment Areas

    On August 9, 2001, the EPA issued guidance on streamlined
maintenance plan provisions for certain moderate PM10
nonattainment areas seeking redesignation to attainment (Memo from
Lydia Wegman, Director, Air Quality Standards and Strategies Division,

entitled ``Limited Maintenance Plan Option for Moderate PM10
Nonattainment Areas'' (LMP Option memo)). The LMP Option memo contains
a statistical demonstration that areas meeting certain air quality
criteria will, with a high degree of probability, maintain the standard
10 years into the future. Thus, the EPA has already provided the
maintenance demonstration for areas meeting the criteria outlined in
the LMP Option memo. It follows that future year emission inventories
for these areas, and some of the standard analyses to determine
transportation conformity with the SIP are no longer necessary.
    To qualify for the LMP Option, the area should have attained the
PM10 NAAQS and, based upon the most recent five years of air
quality data at all monitors in the area, the 24-hour design value
should be at or below 98 [micro]g/m\3\. If an area cannot meet this
test, it may still be able to qualify for the LMP Option if the average
design value (ADV) for the site is less than the site-specific critical
design value (CDV). In addition, the area should expect only limited
growth in on-road motor vehicle PM10 emissions (including
fugitive dust) and should have passed a motor vehicle regional
emissions analysis test. The LMP Option memo also identifies core
provisions that must be included in the LMP. These provisions include
an attainment year emissions inventory, assurance of continued
operation of an EPA-approved air quality monitoring network, and
contingency provisions.

C. Conformity Under the LMP Option

    The transportation conformity rule and the general conformity rule
(40 CFR parts 51 and 93) apply to nonattainment areas and maintenance
areas covered by an approved maintenance plan. Under either conformity
rule, an acceptable method of demonstrating that a Federal action
conforms to the applicable SIP is to demonstrate that expected
emissions from the planned action are consistent with the emissions
budget for the area.
    While EPA's LMP Option does not exempt an area from the need to
affirm conformity, it explains that the area may demonstrate conformity
without conforming to an emissions budget. Under the LMP Option,
emissions budgets are treated as essentially not constraining for the
length of the maintenance period because it is unreasonable to expect
that the qualifying areas would experience so much growth in that
period that a violation of the PM10 NAAQS would result. For
transportation conformity purposes, the EPA would conclude that
emissions in these areas need not be capped for the maintenance period
and therefore a regional emissions analysis would not be required.
Similarly, Federal actions subject to the general conformity rule could
be considered to satisfy the ``budget test'' specified in 40 CFR
93.158(a)(5)(i)(A) for the same reasons that the budgets are
essentially considered to be unlimited.

IV. Review of the Idaho Submittal Addressing the Requirements for
Redesignation and LMPs

A. Has the Pinehurst PM10 NAA attained the applicable NAAQS?

    To demonstrate that an area has attained the PM10 NAAQS,
the IDEQ must submit an analysis of ambient air quality data from an
ambient air monitoring network representing peak PM10
concentrations. The data should be quality-assured and stored in the
EPA Air Quality System database. The EPA has reviewed air quality data
for the area and has determined that the Pinehurst NAA attained the
PM10 NAAQS \1\ by the applicable attainment dates of
December 31, 1994 for the City of Pinehurst and December 31, 2000 for
the Pinehurst PM10 Expansion area, and they continue to
attain the PM10 NAAQS. EPA's analysis is described below.
---------------------------------------------------------------------------

    \1\ Because the annual PM10 standard was revoked
effective December 18, 2006, see 71 FR 61144 (October 17, 2006),
this notice discusses only attainment of the 24-hour PM10
standard.''
---------------------------------------------------------------------------

    The 24-hour PM10 NAAQS is 150 [micro]g/m\3\. An area has
attained this 24-hour standard when the average number of expected
exceedances per year is less than or equal to one, when averaged over a
three-year period (40 CFR 50.6). To make this determination, three
consecutive years of complete ambient air quality data must be
collected in accordance with Federal requirements (40 CFR part 58
including appendices).
    A comprehensive air quality monitoring plan, meeting the
requirements of 40 CFR part 58, was originally submitted by the IDEQ to
the EPA on January 15, 1980, and approved by the EPA on July 28, 1982
(40 CFR 52.670), and most recently submitted in June 2017, with
approval by the EPA on November 8, 2017. The monitoring plan describes
the Idaho monitoring network throughout the state, which includes the
Pinehurst Idaho monitor (AQS ID 16-079-0017-81102-3). In the LMP
submittal, the IDEQ states that the nonattainment designation was based
on data collected at the Pinehurst monitoring site. With the exception
of three high wind exceptional events, a review of data shows that
PM10 3-year average expected exceedances recorded at this
site have been less than or equal to the 24-hour PM10 NAAQS
since 1994. In addition, the IDEQ states that the Pinehurst monitoring
site is operated in compliance with the EPA monitoring guidelines set
forth in 40 CFR part 58, Ambient Air Quality Surveillance.
    Data from the Pinehurst monitoring site has been quality assured by
the IDEQ and submitted to the EPA's Air Quality System (AQS),
accessible through the EPA's AirData website at https://www.epa.gov/outdoor-air-quality-data. To show attainment for the 24-hour
PM10 NAAQS the three-year design value must be less than or
equal to 1.0 expected number of exceedances, as established in Appendix
K to 40 CFR part 50. The Pinehurst monitoring site recorded exceedances
in 2013 and 2015 and the IDEQ flagged these exceedances as being the
result of exceptional events where unusually high winds entrained dust.
Under the EPA's Exceptional Events Rule, the Agency may exclude data
from a regulatory determination related to an exceedance or violation
of the NAAQS if the IDEQ adequately demonstrates that an exceptional
event caused the exceedance or violation. 40 CFR 50.1 and 50.14. For
the reasons set forth in the IDEQ's Pinehurst PM10 2013 High
Wind Exceptional Event concurrence letter and analysis (March 2, 2017),
the EPA excluded data showing an exceedance on September 15, 2013, in
determining whether the Pinehurst NAA has attained the PM10
NAAQS. The concurrence letter explains how the IDEQ met the Exceptional
Event Rule criteria to demonstrate that the September 15, 2013
exceedance qualifies as an exceptional event. Based on this
demonstration, the IDEQ's submission demonstrates that the Pinehurst
PM10 NAA's expected number of exceedances was 0.67 for 2013-
15, which is below the 1.0 upper limit. The EPA confirmed that the area
continues to be less than or equal to the 1.0 expected number
exceedances with the 2014-16 value being 0.7. The EPA therefore finds
that the area was not violating the PM10 NAAQS.

B. Does the Pinehurst PM10 NAA have a fully approved SIP under section
110(k) of the CAA?

    To qualify for redesignation, the SIP for an area must be fully
approved under section 110(k) of the CAA, and must satisfy all
requirements that apply to the area. As discussed in Section II.B.
above, the IDEQ submitted a moderate PM10 SIP for the
Pinehurst PM10 NAA on April 14, 1992. The EPA took final
action to conditionally approve the IDEQ's moderate PM10 SIP
on August

25, 1994 (59 FR 43745) for the City of Pinehurst and to conditionally
approve the IDEQ's moderate PM10 SIP on May 26, 1995 (60 FR
27891) for the Pinehurst PM10 Expansion area. These
conditional approvals required submission of contingency measures.
Accordingly, the IDEQ submitted the contingency plan applicable to the
entire Pinehurst PM10 NAA as required by the conditional
approvals on July 13, 1995. With the EPA's approval on October 2, 2014
(79 FR 59435), the Pinehurst PM10 NAA satisfied all
requirements that apply to the area and thus the area has a fully
approved nonattainment area SIP under section 110(k) of the CAA.

C. Has the IDEQ met all applicable requirements under section 110 and
Part D of the CAA?

    Section 107(d)(3)(E) of the CAA requires that a state containing an
NAA meet all applicable requirements under section 110 and Part D of
the CAA for the area to be redesignated to attainment. The EPA
interprets this to mean that the IDEQ must meet all requirements that
applied to the area prior to, and at the time of, the submission of a
complete redesignation request. The following is a summary of how Idaho
meets these requirements.
1. Clean Air Act Section 110 Requirements
    Section 110(a)(2) of the CAA contains general requirements for
nonattainment plans. These requirements include, but are not limited
to: Submittal of a SIP that has been adopted by the IDEQ after
reasonable notice and public hearing; provisions for establishment and
operation of appropriate apparatus, methods, systems and procedures
necessary to monitor ambient air quality; implementation of a permit
program; provisions for Part C--Prevention of Significant Deterioration
(PSD) and Part D--New Source Review (NSR) permit programs; criteria for
stationary source emission control measures, monitoring and reporting;
provisions for modeling; and provisions for public and local agency
participation. See the General Preamble for further explanation of
these requirements (57 FR 13498, April 16, 1992). The EPA's approval of
Idaho's SIP for attainment and maintenance of national standards can be
found at 40 CFR 52.673. For purposes of redesignation of the Pinehurst
PM10 NAA, the EPA has reviewed the IDEQ SIP and finds that
the IDEQ has satisfied all applicable requirements under CAA section
110(a)(2) for the PM10 NAAQS.
2. Part D Requirements
    Part D of the CAA contains general requirements applicable to all
areas designated nonattainment. The general requirements are followed
by a series of subparts specific to each pollutant. All PM10
nonattainment areas must meet the general provisions of Subpart 1 and
the specific PM10 provisions in Subpart 4, ``Additional
Provisions for Particulate Matter Nonattainment Areas.'' The following
paragraphs discuss these requirements as they apply to the Pinehurst
PM10 NAA.
2a. Part D, Section 172(c)(2)--Reasonable Further Progress
    Section 172(c) contains general requirements for NAA plans. A
thorough discussion of these requirements may be found in the General
Preamble (57 FR 13538, April 16, 1992). CAA section 172(c)(2) requires
nonattainment plans to provide for reasonable further progress (RFP).
Section 171(1) of the CAA defines RFP as ``such annual incremental
reductions in emissions of the relevant air pollutant as are required
by this part (part D of title I) or may reasonably be required by the
Administrator for the purpose of ensuring attainment of the applicable
national ambient air quality standard by the applicable date.'' The
requirements for reasonable further progress, identification of certain
emissions increases and other measures needed for attainment were
satisfied with the approved Pinehurst PM10 NAA SIP (59 FR
43745 and 60 FR 27891). In its August 23, 2001 action (66 FR 44304),
the EPA determined that the Pinehurst NAA attained the 24-hour
PM10 NAAQS by the December 31, 1994 and December 31, 2000,
attainment dates. Therefore, the EPA believes no further showing of RFP
or quantitative milestones is necessary.
2b. Part D, Section 172(c)(3)--Emissions Inventory
    For redesignation, section 172(c)(3) of CAA requires a
comprehensive, accurate, current inventory of actual emissions from all
sources in the Pinehurst PM10 NAA. The IDEQ included an
emissions inventory for the Pinehurst area for the year 2013 in the
September 29, 2017 submittal. The IDEQ used 2013 as a base year for the
emissions inventory, including data from the 2014 periodic emission
inventory (PEI), as the IDEQ determined that it is representative of
emissions during the five-year period associated with air quality data
demonstrating attainment. The IDEQ has demonstrated that the 2013 base
year emissions inventory is current, accurate, and comprehensive, and
therefore meets the requirements of section 172(c)(3) of the CAA.
2c. Part D, Section 172(c)(5)--New Source Review (NSR)
    The CAA requires all nonattainment areas to meet several
requirements regarding NSR. The IDEQ must have an approved major NSR
program that meets the requirements of CAA section 172(c)(5). The Part
D NSR rules for PM10 nonattainment areas in Idaho were
approved by the EPA on July 23, 1993 (58 FR 39445) and amended on
January 16, 2003 (68 FR 2217). Revisions to Idaho's NSR rules were most
recently approved by the EPA on November 26, 2010 (75 FR 72719). Within
the boundaries of the Pinehurst PM10 NAA, the requirements
of the Part D NSR program will be replaced by the IDEQ's Prevention of
Significant Deterioration (PSD) program requirements upon the effective
date of redesignation. The currently approved NSR provisions meet the
requirements of 172(c)(5) and therefore this condition for proposed
redesignation is satisfied.
2d. Part D, Section 172(c)(7)--Compliance With CAA Section 110(a)(2):
Air Quality Monitoring Requirements
    Once an area is redesignated, the IDEQ must continue to operate an
appropriate air monitoring network in accordance with 40 CFR part 58 to
verify the attainment status of the area. On January 15, 1980, the IDEQ
submitted a comprehensive air quality monitoring plan, intended to meet
the requirements of 40 CFR part 58. The EPA approved the plan on July
28, 1982 (40 CFR 52.760). This monitoring plan has been updated, with
the most recent submittal in June 2017, with approval by the EPA on
November 8, 2017. The monitoring plan describes the PM10
monitoring network throughout Idaho, including the Pinehurst monitoring
site. The Pinehurst monitoring site is operated in compliance with the
EPA monitoring guidelines set forth in 40 CFR part 58, Ambient Air
Quality Surveillance. In addition, the Pinehurst PM10 NAA
LMP submittal provides a commitment to continue operation of the
PM10 monitoring network in accordance with 40 CFR part 58,
and to annually verify continued attainment of the 24-hour
PM10 NAAQS in Pinehurst through the Annual Ambient Air
Monitoring Network Plan. Any changes to the monitoring site will be
made via the Annual Ambient Air Monitoring Network Plan or formal
communication. The currently approved monitoring plan

and associated program meet the requirements of 172(c)(7) and therefore
this condition for proposed redesignation is satisfied.
2e. Part D, Section 172(c)(9)--Contingency Measures
    The CAA requires that contingency measures take effect if an area
fails to meet RFP requirements or fails to attain the NAAQS by the
applicable attainment date. On August 23, 2001, the EPA determined that
the Pinehurst NAA attained the PM10 NAAQS by the applicable
attainment dates of December 31, 1994 and December 31, 2000 (66 FR
44304). Therefore, attainment planning contingency measures are no
longer required under section 172(c)(9) of the CAA. However,
maintenance plan contingency provisions are required for maintenance
plans under section 175(a)(d). Please see section IV.I. for a
description of Idaho's maintenance plan contingency provisions.
2f. Part D, Section 189(a), (c) and (e)--Additional Provisions for
Particulate Matter Nonattainment Areas
    CAA sections 189(a), (c) and (e) apply to moderate PM10
nonattainment areas. Any of these requirements which were applicable
and due prior to the submission of the redesignation request must be
fully approved into the SIP before redesignating the area to
attainment. With respect to the Pinehurst NAA, these requirements
include:
    (a) Provisions to assure that reasonably available control measures
were implemented by December 31, 1994 and December 31, 2000 (section
189(a)(1)(C));
    (b) Either a demonstration that the plan provided for attainment as
expeditiously as practicable but not later than December 31, 1994 and
December 31, 2000, or a demonstration that attainment by that date was
impracticable (section 189(a)(1)(B));
    (c) Quantitative milestones which were achieved every three years
and which demonstrate RFP toward attainment by December 31, 1994 and
December 31, 2000 (section 189(c)(1)); and
    (d) Provisions to assure that the control requirements applicable
to major stationary sources of PM10 also apply to major
stationary sources of PM10 precursors except where the
Administrator determined that such sources do not contribute
significantly to PM10 levels which exceed the NAAQS in the
area (section 189(e)).
    Provisions for reasonably available control measures, attainment
demonstration, and RFP milestones were conditionally approved into the
Pinehurst PM10 SIP on August 25, 1994 (59 FR 43745) and on
May 26, 1995 (60 FR 27891). The EPA's approval of the July 13, 1995
contingency plan on October 2, 2014 (79 FR 59435) fully approved these
required elements The EPA approved changes to Idaho's major NSR rules
on July 17, 2012 (77 FR 41916) and November 26, 2010 (75 FR 72719). The
IDEQ's major nonattainment NSR rules and PSD rules include control
requirements that apply to major stationary sources of PM10
and PM10 precursors in nonattainment and attainment/
unclassifiable areas. Therefore, the EPA proposes that the requirements
of 189(a)(c) and (e) for this proposed redesignation is satisfied.

D. Has the IDEQ demonstrated that the air quality improvement is due to
permanent and enforceable reductions?

    Section 107(d)(3)(E)(iii) of the CAA provides that a NAA may not be
redesignated unless the EPA determines that the improvement in air
quality is due to permanent and enforceable reductions in emissions
resulting from implementation of the SIP. Permanent and enforceable
control measures in the Pinehurst PM10 SIP include controls
primarily focused on residential wood combustion. The Pinehurst
PM10 NAA LMP submittal describes its woodstove changeout
program which resulted in 76 stove replacements by 1994 and an
additional 87 replacements between 1996 and 2015. According to a recent
survey in the community these 163 changeouts account for 60% of the
uncertified devices in the area. Between 2015-17, 40 additional
woodstoves have been changed out to cleaner burning devices under this
program; 31 to EPA certified, 1 to propane, and 8 to natural gas.
Additional permanent controls in the area include the weatherization of
30 homes in the mid-1990s which provided for reductions in emissions by
reducing home heating requirements which in turn reduce the need for
additional fuel and the associated emissions.

E. Does the area have a fully approved maintenance plan pursuant to
section 175A of the act?

    In this action, we are proposing to approve the LMP in accordance
with the principles outlined in the LMP Option Memo. Upon final
approval, the Pinehurst NAA will have a fully approved maintenance
plan.

F. Has the IDEQ demonstrated that the Pinehurst NAA qualifies for the
LMP Option?

    The LMP Option Memo outlines the requirements for an area to
qualify for a LMP. First, the area should be attaining the NAAQS. On
August 23, 2001, the EPA determined that the Pinehurst NAA attained the
PM10 NAAQS by December 31, 1994 and December 31, 2000 (66 FR
44304). The EPA has reviewed recent ambient air quality data for the
24-hour PM10 NAAQS, and has determined that the Pinehurst
NAA continues to attain the 24-hour PM10 NAAQS. Please see
section IV.A. above for a detailed discussion.
    Second, the average design value (ADV) for the past five years of
monitoring data must be at or below the critical design value (CDV).
The CDV is a margin of safety value at which an area has been
determined to have a one in ten probability of exceeding the NAAQS. The
LMP Option Memo provides two methods to review monitoring data for the
purpose of determining qualification for an LMP. The first method is a
comparison of a site's ADV with the CDV of 98 [micro]g/m\3\ for the 24-
hour PM10 NAAQS. A second method that applies to the 24-hour
PM10 NAAQS is the calculation of a site-specific CDV and a
comparison of the site-specific CDV with the ADV for the past five
years of monitoring data. The IDEQ's LMP submittal provides a
comparison of five-year ADVs compared to the 24-hour and annual CDVs,
as described in the first method for review of monitoring data to
determine qualification for a LMP. The IDEQ's analysis demonstrates
that the Pinehurst NAA has met the LMP design value criteria using the
tabular look up method which showed the area to be meeting the CDV with
a five-year design value of 83 [micro]g/m\3\. The EPA has reviewed the
calculations and concurs with the IDEQ's findings that the area has a
five-year design value of 83 [micro]g/m\3\ for both 2011-2015 and the
most recently available five year DV of 2012-2016.\2\ Therefore, the
EPA finds that the Pinehurst NAA meets the design value criteria
outlined in the LMP Option Memo.
---------------------------------------------------------------------------

    \2\ This LMP design value is dependent upon data being excluded
from a high wind exceptional event also proposed for approval in
this notice.
---------------------------------------------------------------------------

    Third, the area must meet the motor vehicle regional emissions
analysis test described in attachment B of the LMP Option Memo. Using
the methodology outlined in the LMP Option Memo, the IDEQ has submitted
an analysis of whether increased emissions from on-

road mobile sources would increase PM10 concentrations in
the Pinehurst NAA to levels that would threaten the assumption of
maintenance that underlies the LMP policy. Using this methodology, the
IDEQ has determined that the Pinehurst NAA passes the motor vehicle
regional emissions analysis test. The motor vehicle regional emissions
analysis test results of 83.19 [micro]g/m\3\ and 83.36 [micro]g/m\3\
when adjusted for growth are below the 98 [micro]g/m\3\ annual standard
and meet the margin of safety requirements. The EPA has reviewed the
calculations in the IDEQ's Pinehurst NAA LMP submittal in Section 3.1
and concurs with this conclusion.
    The LMP Option Memo requires all controls relied on to demonstrate
attainment remain in place for a NAA to qualify for a LMP. The LMP
developed by IDEQ will continue to implement the control measures
relied upon to demonstrate attainment. Therefore, EPA proposes to find
that the Pinehurst PM10 NAA meets the qualification criteria
set forth in the LMP Option Memo, and therefore qualifies for a LMP.
    The LMP Option Memo also indicates that once a state submits a LMP
and it is in effect, the IDEQ will be expected to determine, on an
annual basis, that the LMP criteria are still being met. If the IDEQ
determines that the LMP criteria are not being met, it should take
action to reduce PM10 concentrations enough to requalify for
the LMP. One possible approach the IDEQ could take is to implement
contingency measures. Section IV.I. provides a description of
contingency provisions submitted as part of the Pinehurst NAA LMP
submittal. The EPA believes the contingency provisions submitted by the
IDEQ meet the requirements of CAA section 175A as outlined in the LMP
Option memo.

G. Does the IDEQ have an approved attainment emissions inventory which
can be used to demonstrate attainment of the NAAQS?

    Pursuant to the LMP Option Memo, the IDEQ's approved attainment
plan should include an emissions inventory which can be used to
demonstrate attainment of the NAAQS. The inventory should represent
emissions during the same five-year period associated with air quality
data used to determine whether the area meets the applicability
requirements of the LMP Option. The IDEQ should review its inventory
every three years to ensure emissions growth is incorporated in the
inventory if necessary.
    The IDEQ's Pinehurst PM10 NAA LMP submittal includes an
emissions inventory, with a base year of 2013. After reviewing the 2013
emissions inventory and determining that it is current, accurate and
complete, as well as reviewing monitoring data, the EPA has determined
that the 2013 emissions inventory is representative of the attainment
year inventory because the NAAQS was not violated during 2013. In
addition, the year 2013 is representative of the level of emissions
during the time period used to calculate the average design value
because 2013 is one of the years during the five-year period used to
calculate the design value. The submittal meets EPA guidance, as
described above, for purposes of an attainment emissions inventory.

H. Does the LMP include an assurance of continued operation of an
appropriate EPA-approved air quality monitoring network, in accordance
with 40 CFR part 58?

    A PM10 monitoring network was established in the
Pinehurst area in 1985. The monitoring network was developed and has
been maintained in accordance with Federal siting and design criteria
in 40 CFR part 58, and in consultation with EPA Region 10. The EPA most
recently approved the IDEQ's air monitoring plan on November 8, 2017.
In the Pinehurst PM10 NAA LMP submittal, the IDEQ commits to
continue to operate its monitoring network to meet the EPA requirements
at 40 CFR part 58 and identify any issues or adjustments via the Annual
Ambient Air Monitoring Network Plan or formal communication. The
submittal contains an assurance of continued operation of the
PM10 monitoring network. The submittal meets EPA LMP
submission requirements with respect to maintenance of a monitoring
network.

I. Does the plan meet the clean air act requirements for contingency
provisions?

    The CAA section 175A states that a maintenance plan must include
contingency provisions, as necessary, to ensure prompt correction of
any violation of the NAAQS which may occur after redesignation of the
area to attainment. As explained in the LMP Option Memo and the
Calcagni Memo, these contingency provisions are considered to be an
enforceable part of the federally-approved SIP. The maintenance plan
should clearly identify the provisions to be adopted, a schedule and
procedures for adoption and implementation, and a specific time limit
for action by the IDEQ. The maintenance plan should identify the events
that would ``trigger'' the adoption and implementation of a contingency
provision, the contingency provision that would be adopted and
implemented, and the schedule indicating the time frame by which the
IDEQ would adopt and implement the provision. The LMP Option Memo and
Calcagni Memo state that the EPA will determine the adequacy of a
contingency plan on a case-by-case basis. At a minimum, it must require
that the IDEQ will implement all measures contained in the CAA part D
nonattainment plan for the area prior to redesignation.
    In the Pinehurst PM10 NAA LMP submittal, the IDEQ has
included maintenance plan contingency provisions to ensure the area
continues to meet the PM10 NAAQS. The submitted LMP includes
the Annual Network Plan review process as the triggering mechanism for
identifying if the Pinehurst area violates the PM10 NAAQS.
If triggered the LMP identifies a list of specific control measures as
listed in section 3.5.2 of their submittal to reduce emissions,
including potential measures that would control emissions associated
with residential wood combustion, controlling road-dust related
emissions, and refuse burning for evaluation and a process for
selection. Therefore, the EPA believes the contingency provisions
submitted in the Pinehurst PM10 NAA LMP are adequate to meet
CAA section 175A requirements.

J. How is conformity treated under a limited maintenance plan? \3\
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    \3\ See ``Limited Maintenance Plan Option for Moderate
PM10 Nonattainment Areas'' memo from Director Lydia
Wegman to Regional Offices dated August 9, 2001.
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    The transportation conformity rule (40 CFR 51. 390 and 40 CFR
93.100-129) and the general conformity rule (40 CFR 93.150-165) apply
to nonattainment areas and maintenance areas operating under
maintenance plans. Under either conformity rule one means of
demonstrating conformity of Federal actions is to indicate that
expected emissions from planned actions are consistent with the
emissions budget for the area. Emissions budgets in LMP areas may be
treated as essentially not constraining for the length of the
maintenance period because it is unreasonable to expect that an area
satisfying the LMP criteria will experience so much growth during that
period of time such that a violation of the PM10 NAAQS would
result. While this policy does not exempt an area from the need to
affirm conformity, it does allow the area to demonstrate

conformity without undertaking certain requirements of these rules. For
transportation conformity purposes, EPA would be concluding that
emissions in these areas need not be capped for the maintenance period,
and, therefore, a regional emissions analysis would not be required.
Similarly, Federal actions subject to the general conformity rule could
be considered to satisfy the ``budget test'' specified in Sec.
93.158(a)(5)(i)(A) of the rule, for the same reasons that the budgets
are essentially considered to be unlimited.
    The Pinehurst area is an isolated rural area \4\. Transportation
conformity determinations in isolated rural nonattainment and
maintenance areas are required only when a new non-exempt Federal
Highway Administration (FHWA)/State Transportation Agency (STA) project
needs funding or approval. Thus, in the event that a conformity
analysis is required, the state agency responsible for conducting
transportation conformity must document and ensure that:
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    \4\ As defined in 40 CFR 93.101, Isolated rural nonattainment
and maintenance areas are areas that do not contain or are not part
of any metropolitan planning area as designated under the
transportation planning regulations. Isolated rural areas do not
have Federally required metropolitan transportation plans (MTPs) or
transportation improvement programs (TIPs) and do not have projects
that are part of the emissions analysis of any metropolitan planning
organization's (MPO's) MTP or TIP. Projects in such areas are
instead included in statewide transportation improvement programs.
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    (a) The interagency consultation procedures meet the applicable
requirements of 40 CFR 93.105(c)(1)(vi);
    (b) Conformity is determined as specified in 40 CFR 93.109(g) for
isolated rural areas.
    The minimum criteria by which the EPA determines whether a SIP is
adequate for conformity purposes are specified at 40 CFR 93.118(e)(4).
The EPA's analysis of how the LMP satisfies these criteria for
transportation conformity is found in the docket. The EPA proposes to
find adequate Idaho's LMP for Pinehurst for transportation conformity
purposes.
    Upon final approval of the Pinehurst PM10 NAA LMP, the
Pinehurst area will be exempt from performing a regional emissions
analysis, but must meet project-level conformity analysis as well as
the transportation conformity criteria located in 40 CFR 93.109(g) for
isolated rural areas.

V. 2013 PM[bdi1][bdi0] High Wind Exceptional Event

    The CAA allows for the exclusion of air quality monitoring data
from design value calculations when there are exceedances caused by
events, such as wildfires or high wind events, that meet the criteria
for an exceptional event identified in the EPA's implementing
regulations, the Exceptional Events Rule at 40 CFR 50.1, 50.14 and
51.930. In 2013 emissions from a high wind event entrained dust and
impacted PM10 concentrations recorded at the Pinehurst
monitor. For purposes of this Pinehurst PM10 redesignation
and LMP, the IDEQ submitted an exceptional event demonstration to
request exclusion of the data. The EPA evaluated the IDEQ's exceptional
event demonstration for the flagged values of the 24-hour
PM10 NAAQS for September 15, 2013, at the monitor in
Pinehurst, Idaho, with respect to the requirements of the EPA's
Exceptional Events Rule (40 CFR 50.14) and determined that IDEQ met the
rule requirements. On March 2, 2017, the EPA concurred with the IDEQ's
request to exclude event-influenced data for September 15, 2013. As
such, the event-influenced data have been removed from the data set
used for regulatory purposes and, for this proposed action, the EPA
relies on the calculated values that exclude the event-influenced data.
The EPA now proposes approval of the IDEQ's request to exclude data
from September 15, 2013, in determining PM10 attainment as a
high wind exceptional event. For further information, refer to the
IDEQ's Exceptional Event demonstration package and the EPA's
concurrence and analysis located in the docket for this regulatory
action.

VI. West Silver Valley 2012 Annual PM[bdi2].[bdi5] Emission
Inventory

A. Requirements for Emissions Inventories

    Section 172(c)(3) of the CAA requires a state with an area
designated as nonattainment to submit a ``comprehensive, accurate,
current inventory of actual emissions from all sources of the relevant
pollutant'' for the NAA. By requiring an accounting of actual emissions
from all sources of the relevant pollutants in the area, this section
provides for the base year inventory to include all emissions from
sources in the NAA that contribute to the formation of a particular
NAAQS pollutant. For the 2012 annual PM2.5 NAAQS, this
includes direct PM2.5 (condensable and filterable) as well
as the precursors to the formation of secondary PM2.5:
Nitrogen oxides (NOX), sulfur dioxide (SO2),
volatile organic compounds (VOCs), and ammonia (NH3) (40 CFR
51.1008; 81 FR 58028). Inclusion of PM2.5 and all of the
PM2.5 precursors in the emissions inventory is necessary in
order to inform other aspects of the attainment plan development
process, if such a plan is required. The SIP submission should include
documentation explaining how the state calculated the emissions data
for the base year inventory. The specific PM2.5 emissions
inventory requirements are set forth in 40 CFR 51.1008. The EPA has
provided additional guidance for developing PM2.5 emissions
inventories in Emissions Inventory Guidance for Implementation of Ozone
and Particulate Matter National Ambient Air Quality Standards (NAAQS)
and Regional Haze.

B. West Silver Valley PM2.5 Base Year Emissions Inventory

    The IDEQ developed a 2013 base year emissions inventory for the WSV
annual PM2.5 NAA. The base year emissions inventory includes
data from 2013 and 2014 and in large part was extracted from the 2014
periodic emissions inventory (PEI) which is used to populate the EPA's
National Emissions Inventory (NEI). The 2013 base year inventory is one
of the three years used to designate the area as nonattainment. This
base year inventory presents direct PM2.5 emissions
(condensable and filterable) and emissions of all PM2.5
precursors (NOX, VOCs, NH3, and SO2)
to meet the emissions inventory requirements of CAA section 172(c). The
IDEQ provided inventories from all sources in the WSV NAA, including
nonpoint/area sources, point sources, nonroad sources, and onroad
sources. The inventory is based on annual emissions in tons per year.
The top source sectors of direct PM2.5 in the WSV are
prescribed burns (88.91 tons/year (tpy)), residential wood combustion
(52.61 tpy), onroad (17.25 tpy), unpaved roads (13.61 tpy), and nonroad
(7.24 tpy) emissions.
    The largest source category of direct PM2.5 emissions in
the WSV was from prescribed burning, accounting for 44.9% of direct
PM2.5. These emissions came from primarily large and small
scale permitted burners who burn forest waste mostly during the fall
season. Emissions were estimated by extracting data, including fuel
loading-moisture-acres burned-emissions factors, from prescribed burn
databases maintained by the Idaho-Montana Air Shed Group and Idaho
Department of Lands, and the Forest Practices Act Compliance database.
The second largest source category is residential wood combustion
(RWC). The emissions come from various residential devices designed to
heat homes through burning wood whether in solid or pellet form.

Emissions from RWC, on an annual basis, account for about 26.6% of the
base year direct PM2.5 emissions. These emissions were
estimated using the EPA's Microsoft Access RWC tool v2.1 and estimates
were adjusted with information from a local woodstove survey along with
information from the ongoing woodstove changeout program in the area.
The next three largest source categories, onroad emissions, unpaved
roads emission, and nonroad emissions accounted for 30.9% of the direct
PM2.5 in the base year emissions inventory. The onroad
emissions source category includes emissions from motor vehicles and
road dust from paved roads. The nonroad emissions source category
includes winter and summer recreation vehicles and emissions generated
from logging, construction and mining, and other minor nonroad sources.
Onroad and nonroad emissions were calculated using MOVES2014.

C. EPA's Evaluation

    The EPA has reviewed the results, procedures, and methodologies for
the WSV Annual PM2.5 NAA base year emissions inventory. The
EPA has determined that the 2013 base year inventory for the WSV is
based on the most current and accurate information available to the
IDEQ at the time the inventories were being developed. The inventories
comprehensively address all source categories in the WSV NAA, actual
emissions are provided, and appropriate procedures were used to develop
the inventories. We are proposing to approve the 2013 base year
emissions inventory for the WSV NAA as meeting the requirements of CAA
section 172(c)(3) and 40 CFR 51.1008(a)(1).

VII. Proposed Action

    The EPA is proposing to approve the Pinehurst PM10 NAA
LMP submitted by the IDEQ for the Pinehurst NAA and concurrently
redesignate the area to attainment for the PM10 NAAQS. The
EPA has reviewed air quality data for the area and determined that the
Pinehurst NAA attained the PM10 NAAQS by the required
attainment date, and that air monitoring data continue to show
attainment. The EPA is proposing to approve that the Pinehurst
PM10 NAA LMP meets all of the requirements of an LMP and
that the Pinehurst NAA meets all of the requirements of redesignation
as described in this action.
    The EPA is also taking action to propose approval of the September
15, 2013, high wind exceptional event that impacted PM10
values in the area.
    The EPA is also taking action to propose approval of the WSV Annual
PM2.5 base year Emissions Inventory as meeting CAA 172(c)(3)
requirements.

VIII. Statutory and Executive Order Reviews

    Under the CAA, 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, the EPA's role is to approve state choices,
provided that they meet the criteria of the CAA. Accordingly, this
proposed action merely approves state law as meeting Federal
requirements and does not impose additional requirements beyond those
imposed by state law. For that reason, this proposed action:
     Is not a ``significant regulatory action'' subject to
review by the Office of Management and Budget under Executive Orders
12866 (58 FR 51735, October 4, 1993) and 13563 (76 FR 3821, January 21,
2011);
     Is not an Executive Order 13771 (82 FR 9339, February 2,
2017) regulatory action because SIP approvals are exempted under
Executive Order 12866;
     Does not impose an information collection burden under the
provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.);
     Is certified as not having a significant economic impact
on a substantial number of small entities under the Regulatory
Flexibility Act (5 U.S.C. 601 et seq.);
     Does not contain any unfunded mandate or significantly or
uniquely affect small governments, as described in the Unfunded
Mandates Reform Act of 1995 (Pub. L. 104-4);
     Does not have Federalism implications as specified in
Executive Order 13132 (64 FR 43255, August 10, 1999);
     Is not an economically significant regulatory action based
on health or safety risks subject to Executive Order 13045 (62 FR
19885, April 23, 1997);
     Is not a significant regulatory action subject to
Executive Order 13211 (66 FR 28355, May 22, 2001);
     Is not subject to requirements of section 12(d) of the
National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272
note) because it does not involve technical standards; and
     Does not provide the 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 the 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 and will not impose substantial
direct costs on tribal governments or preempt tribal law as specified
by Executive Order 13175 (65 FR 67249, November 9, 2000).

List of Subjects

40 CFR Part 52

    Environmental protection, Air pollution control, Incorporation by
reference, Intergovernmental relations, Particulate matter, Reporting
and recordkeeping requirements.

40 CFR Part 81

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

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

    Dated: April 30, 2018.
Chris Hladick,
Regional Administrator, Region 10.
[FR Doc. 2018-09992 Filed 5-10-18; 8:45 am]
 BILLING CODE 6560-50-P


[Federal Register Volume 79, Number 97 (Tuesday, May 20, 2014)]
[Notices]
[Page 28982]
[FR Doc No: 2014-11575]

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SECURITIES AND EXCHANGE COMMISSION

Submission for OMB Review; Comment Request

Upon Written Request Copies Available From: Securities and Exchange
Commission, Office of Investor Education and Advocacy, Washington, DC
20549-0213.

Extension:
     Form CB., SEC File No. 270-457, OMB Control No. 3235-0518.

    Notice is hereby given that, pursuant to the Paperwork Reduction
Act of 1995 (44 U.S.C. 3501 et seq.), the Securities and Exchange
Commission (``Commission'') has submitted to the Office of Management
and Budget this request for extension of the previously approved
collection of information discussed below.
    Form CB (17 CFR 239.800) is a document filed in connection with a
tender offer for a foreign private issuer. This form is used to report
an issuer tender offer conducted in compliance with Exchange Act Rule
13e-4(h)(8) (17 CFR 240.13e-4(h)(8)), a third-party tender offer
conducted in compliance with Exchange Act Rule 14d-1(c) (17 CFR
240.14d-1(c)) and a going private transaction conducted in accordance
with Rule 13e-3(g)(6) (17 CFR 240.13e-3(g)(6). Form CB is also used by
a subject company pursuant to Exchange Act Rule 14e-2(d) (17 CFR
240.14e-2(d)). This information is made available to the public.
Information provided on Form CB is mandatory. Form CB takes
approximately 0.5 hours per response to prepare and is filed by
approximately 200 respondents annually. We estimate that 25% of the 0.5
hours per response (0.125 hours) is prepared by the respondent for an
annual reporting burden of 25 hours (0.125 hours per response x 200
responses).
    An agency may not conduct or sponsor, and a person is not required
to respond to, a collection of information unless it displays a
currently valid control number.
    The public may view the background documentation for this
information collection at the following Web site, www.reginfo.gov.
Comments should be directed to: (i) Desk Officer for the Securities and
Exchange Commission, Office of Information and Regulatory Affairs,
Office of Management and Budget, Room 10102, New Executive Office
Building, Washington, DC 20503, or by sending an email to<EMAIL_ADDRESS>and (ii) Thomas Bayer, Director/Chief Information
Officer, Securities and Exchange Commission, c/o Remi Pavlik-Simon, 100
F Street NE., Washington, DC 20549 or send an email to<EMAIL_ADDRESS>Comments must be submitted to OMB within 30 days of
this notice.

    Dated: May 14, 2014.
Kevin M. O'Neill,
Deputy Secretary.
[FR Doc. 2014-11575 Filed 5-19-14; 8:45 am]
BILLING CODE 8011-01-P