[Federal Register Volume 84, Number 145 (Monday, July 29, 2019)]
[Proposed Rules]
[Pages 36516-36534]
[FR Doc No: 2019-15797]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R08-OAR-2019-0140; FRL-9996-89-Region 8]

Promulgation of State Implementation Plan Revisions;
Infrastructure Requirements for the 2015 Ozone National Ambient Air
Quality Standards; Colorado and North Dakota

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: On October 1, 2015, the Environmental Protection Agency (EPA)
promulgated the 2015 ozone NAAQS, revising the standard to 0.070 parts
per million. Whenever a new or revised National Ambient Air Quality
Standard (NAAQS) is promulgated, the Clean Air Act (CAA or Act)
requires each state to submit a State Implementation Plan (SIP)
revision for the implementation, maintenance, and enforcement of the
new standard. This submission is commonly referred to as an
infrastructure SIP. In this action we are proposing to approve multiple
elements and disapprove a single element of the following
infrastructure SIP submissions with respect to infrastructure
requirements for the 2015 ozone NAAQS: Colorado, submitted to the EPA
on September 17, 2018; and North Dakota, submitted to the EPA on
November 6, 2018. We are also proposing to approve a portion of North
Dakota's May 2, 2019 submission of chapter 33.1-15-15, the air
pollution control rules of the State of North Dakota, that updates the
date of incorporation by reference (IBR) of Federal rules.

DATES: Written comments must be received on or before August 28, 2019.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-R08-
OAR-2019-0140, to the Federal Rulemaking Portal: https://www.regulations.gov. Follow the online instructions for submitting
comments. Once submitted, comments cannot be edited or removed from
www.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.
    Docket: All documents in the docket are listed in the
www.regulations.gov index. Although listed in the index, some
information is not publicly available, e.g., CBI or other information
whose disclosure is restricted by statute. Certain other material, such
as copyrighted material, will be publicly available only in hard copy.
Publicly available docket materials are available either electronically
in www.regulations.gov or in hard copy at the Air and Radiation
Division, Environmental Protection Agency (EPA), Region 8, 1595 Wynkoop
Street, Denver, Colorado 80202-1129. The EPA requests that if at all
possible, you contact the individual listed in the FOR FURTHER
INFORMATION CONTACT section to view the hard copy of the docket. You
may view the hard copy of the docket Monday through Friday, 8:00 a.m.
to 4:00 p.m., excluding Federal holidays.

FOR FURTHER INFORMATION CONTACT: Amrita Singh,<PHONE_NUMBER>,
<EMAIL_ADDRESS>or Clayton Bean,<PHONE_NUMBER>,
<EMAIL_ADDRESS>Mail can be directed to the Air and Radiation
Division, U.S. EPA, Region 8, Mail-code 8ARD-QP, 1595 Wynkoop Street,
Denver, Colorado 80202-1129.

SUPPLEMENTARY INFORMATION: Throughout this document, ``reviewing
authority,'' ``we,'' ``us,'' and ``our'' refer to the EPA.

Table of Contents

I. Background
    A. What infrastructure elements are required under sections
110(a)(1) and (2)?
    B. How did the states address the infrastructure elements of
sections 110(a)(1) and (2)?
    1. Colorado
    2. North Dakota
II. What is the scope of this proposed rule?
III. The EPA's Evaluation of the State Submittals
    A. CAA Section 110(a)(2)(A): Emission Limits and Other Control
Measures

    1. Colorado
    2. North Dakota
    B. CAA Section 110(a)(2)(B): Ambient Air Quality Monitoring/Data
System
    1. Colorado
    2. North Dakota
    C. CAA Section 110(a)(2)(C): Program for Enforcement of Control
Measures
    1. Colorado
    2. North Dakota
    D. CAA Section 110(a)(2)(D): Interstate Transport
    1. Colorado
    Prongs 1 and 2: Significant Contribution to Nonattainment and
Interference With Maintenance
    Prong 3: Interference With PSD Measures
    Prong 4: Interference With Measures to Protect Visibility
    110(a)(2)(D)(ii): Interstate and International Transport
Provisions
    2. North Dakota
    Prongs 1 and 2: Significant Contribution to Nonattainment and
Interference With Maintenance
    Prong 3: Interference With PSD Measures
    Prong 4: Interference With Measures to Protect Visibility
    110(a)(2)(D)(ii): Interstate and International Transport
Provisions
    E. CAA Section 110(a)(2)(E): Adequate Resources
    1. Colorado
    2. North Dakota
    F. CAA Section 110(a)(2)(F): Stationary Source Monitoring System
    1. Colorado
    2. North Dakota
    G. CAA Section 110(a)(2)(G): Emergency Episodes
    1. Colorado
    2. North Dakota
    H. CAA Section 110(a)(2)(H): Future SIP Revisions
    1. Colorado
    2. North Dakota
    I. CAA Section 110(a)(2)(I): Nonattainment Area Plan Revision
Under Part D
    J. CAA Section 110(a)(2)(J): Consultation With Government
Officials, Public Notification, PSD and Visibility Protection
    1. Colorado
    2. North Dakota
    K. CAA Section 110(a)(2)(K): Air Quality and Modeling/Data
    1. Colorado
    2. North Dakota
    L. CAA Section 110(a)(2)(L): Permitting Fees
    1. Colorado
    2. North Dakota
    M. CAA Section 110(a)(2)(M): Consultation/Participation by
Affected Local Entities
    1. Colorado
    2. North Dakota
    N. Revisions to North Dakota Air Pollution Control Rules
IV. Proposed Action
    Table 1: Infrastructure Elements That the EPA Is Proposing To
Act On
V. Incorporation by Reference
VI. Statutory and Executive Orders Review

I. Background

    On March 12, 2008, the EPA promulgated a new NAAQS for ozone,
revising the levels of the primary and secondary 8-hour ozone standards
from 0.08 parts per million (ppm) to 0.075 ppm (73 FR 16436). More
recently, on October 1, 2015, the EPA promulgated and revised the NAAQS
for ozone, further strengthening the primary and secondary 8-hour
standards to 0.070 ppm (80 FR 65292). The October 1, 2015 standards are
known as the 2015 ozone NAAQS.
    Under sections 110(a)(1) and (2) of the CAA, after the promulgation
of a new or revised NAAQS states are required to submit infrastructure
SIPs to ensure their SIPs provide for implementation, maintenance, and
enforcement of the NAAQS. These submissions must contain any revisions
needed for meeting the applicable SIP requirements of section
110(a)(2), or certifications that the existing SIPs already meet those
requirements. The EPA highlighted this statutory requirement in an
October 2, 2007 guidance document entitled ``Guidance on SIP Elements
Required Under Sections 110(a)(1) and (2) for the 1997 8-hour Ozone and
PM2.5 National Ambient Air Quality Standards'' (2007 Memo).
On September 25, 2009, the EPA issued an additional guidance document
pertaining to the 2006 PM2.5 NAAQS entitled ``Guidance on
SIP Elements Required Under Sections 110(a)(1) and (2) for the 2006 24-
Hour Fine Particle (PM2.5) National Ambient Air Quality
Standards (NAAQS)'' (2009 Memo), followed by the October 14, 2011
``Guidance on Infrastructure SIP Elements Required Under Sections
110(a)(1) and (2) for the 2008 Lead (Pb) National Ambient Air Quality
Standards (NAAQS)'' (2011 Memo). Most recently, the EPA issued
``Guidance on Infrastructure State Implementation Plan (SIP) Elements
under Clean Air Act Sections 110(a)(1) and (2)'' on September 13, 2013
(2013 Memo).

A. What infrastructure elements are required under sections 110(a)(1)
and (2)?

    CAA section 110(a)(1) provides the procedural and timing
requirements for SIP submissions after a new or revised NAAQS is
promulgated. Section 110(a)(2) lists specific elements the SIP must
contain or satisfy. These infrastructure elements include requirements
such as modeling, monitoring, and emissions inventories, which are
designed to assure attainment and maintenance of the NAAQS. The
elements that are the subject of this action are listed below.
     110(a)(2)(A): Emission limits and other control measures.
     110(a)(2)(B): Ambient air quality monitoring/data system.
     110(a)(2)(C): Program for enforcement of control measures.
     110(a)(2)(D): Interstate transport.
     110(a)(2)(E): Adequate resources and authority, conflict
of interest, and oversight of local governments and regional agencies.
     110(a)(2)(F): Stationary source monitoring and reporting.
     110(a)(2)(G): Emergency powers.
     110(a)(2)(H): Future SIP revisions.
     110(a)(2)(J): Consultation with government officials;
public notification; and PSD and visibility protection.
     110(a)(2)(K): Air quality modeling/data.
     110(a)(2)(L): Permitting fees.
     110(a)(2)(M): Consultation/participation by affected local
entities.
    A detailed discussion of each of these elements for Colorado and
North Dakota is contained in section III of this document.

B. How did the states address the infrastructure elements of sections
110(a)(1) and (2)?

    The Colorado and North Dakota 2015 ozone NAAQS infrastructure SIP
submissions demonstrate how the states, where applicable, have plans in
place that meet the requirements of section 110 for the 2015 ozone
NAAQS. The state submittals are available within the electronic docket
for today's proposed action at www.regulations.gov.
1. Colorado
    The Colorado Department of Public Health and Environment (CDPHE)
submitted a certification of Colorado's infrastructure SIP for the 2015
ozone NAAQS on September 17, 2018. The State's submission references
the current Air Quality Control Commission (AQCC) regulations and
Colorado Revised Statutes (C.R.S.). The AQCC regulations referenced in
the submittal are publicly available at https://www.colorado.gov/pacific/cdphe/aqcc-regs and http://www.lexisnexis.com/hottopics/colorado/. Colorado's approved SIP can be found at 40 CFR 52.320.
2. North Dakota
    The North Dakota Department of Health/Department of Environmental
Quality (NDEQ) \1\ submitted certification

for North Dakota's infrastructure SIP for the 2015 ozone NAAQS on
November 6, 2018. The State's submission references the North Dakota
Century Code (NDCC) and the North Dakota Air Pollution Control Rules
(APCR) contained in the North Dakota Administrative Code (NDAC). The
NDCC and NDAC referenced in the submittals are publicly available at
http://www.legis.nd.gov/general-information/north-dakota-century-code
and http://www.legis.nd.gov/cencode/t23c25.html. North Dakota's
approved SIP can be found at 40 CFR 52.1820.
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    \1\ The EPA notes that the North Dakota state legislature
created the North Dakota Department of Environmental Quality (NDEQ)
in 2017. The EPA approved changes to the North Dakota SIP for
purposes of transferring authority from the North Dakota Department
of Health (NDDH) to the NDEQ. We approved the transfer of authority
to implement and enforce the EPA-approved SIP on February 5, 2019
(84 FR 1610). We also approved a recodification of the state's
previously-approved APCR. Given this transfer of authority and
change in numbering of North Dakota's codified regulations, the
state's submittal for this proposed action references rules and
regulations prior to the EPA's final approval, but under the new
codification. See also, 84 FR 8260, March 7, 2019.
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II. What is the scope of this proposed rule?

    The EPA is acting upon the SIP submissions from Colorado and North
Dakota that address the infrastructure requirements of CAA sections
110(a)(1) and 110(a)(2) for the 2015 ozone NAAQS. The requirement for
states to make a SIP submission of this type arises out of CAA section
110(a)(1). Pursuant to section 110(a)(1), states must make SIP
submissions ``within 3 years (or such shorter period as the
Administrator may prescribe) after the promulgation of a national
primary ambient air quality standard (or any revision thereof),'' and
these SIP submissions are to provide for the ``implementation,
maintenance, and enforcement'' of such NAAQS. The statute directly
imposes on states the duty to make these SIP submissions, and the
requirement to make the submissions is not conditioned upon the EPA
taking any action other than promulgating a new or revised NAAQS.
Section 110(a)(2) includes a list of specific elements that ``[e]ach
such plan'' submission must address.
    Whenever the EPA promulgates a new or revised NAAQS, CAA section
110(a)(1) requires states to make SIP submissions to provide for the
implementation, maintenance, and enforcement of the NAAQS. This
particular type of SIP submission is commonly referred to as an
``infrastructure SIP.'' These submissions must meet the various
requirements of CAA section 110(a)(2), as applicable. Due to ambiguity
in some of the language of CAA section 110(a)(2), the EPA finds that it
is appropriate to interpret these provisions in the specific context of
acting on infrastructure SIP submissions. The EPA has previously
provided comprehensive guidance on the application of these provisions
through a guidance document for infrastructure SIP submissions and
through regional actions on infrastructure submissions.\2\ Unless
otherwise noted below, we are following that existing approach in
acting on this submission. In addition, in the context of acting on
such infrastructure submissions, the EPA evaluates the state's SIP for
facial compliance with statutory and regulatory requirements, not for
the state's implementation of its SIP.\3\ The EPA has other authority
to address any issues concerning a state's implementation of the rules,
regulations, consent orders, etc. that comprise its SIP.
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    \2\ The EPA explains and elaborates on these ambiguities and its
approach to address them in its September 13, 2013 Infrastructure
SIP Guidance (available at https://www3.epa.gov/airquality/urbanair/sipstatus/docs/. Guidance on
Infrastructure_SIP_Elements_Multipollutant_FINAL_Sept_2013.pdf), as
well as in numerous agency actions, including the EPA's prior action
on South Dakota's infrastructure SIP to address 1997 and 2006
PM2.5, 2008 Lead, 2008 Ozone, and 2010 NO2
NAAQS (79 FR 71040, (December 1, 2014)).
    \3\ See U.S. Court of Appeals for the Ninth Circuit decision in
Montana Environmental Information Center v. EPA, No. 16-71933
(August 30, 2018).
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III. The EPA's Evaluation of the State Submittals

A. CAA Section 110(a)(2)(A): Emission Limits and Other Control Measures

    Section 110(a)(2)(A) requires SIPs to include enforceable emission
limitations and other control measures, means, or techniques (including
economic incentives such as fees, marketable permits, and auctions of
emissions rights), as well as schedules and timetables for compliance
as may be necessary or appropriate to meet the applicable requirements
of the Act.
1. Colorado
    The State's submission and the EPA's analysis:
    Multiple SIP-approved AQCC regulations cited in Colorado's
certifications provide enforceable emission limitations and other
control measures, means or techniques, schedules for compliance, and
other related matters necessary to meet the requirements of the CAA
section 110(a)(2)(A) for the 2015 NAAQS subject to the following
clarification.
    The EPA does not consider SIP requirements triggered by the
nonattainment area mandates in part D of Title I of the CAA to be
governed by the submission deadline of section 110(a)(1). Nevertheless,
Colorado has included some SIP provisions originally submitted in
response to part D requirements in its certification for the
infrastructure requirements of section 110(a)(2).). For the purposes of
this action, the EPA is reviewing any rules originally submitted in
response to part D requirements solely for the purposes of determining
whether they support a finding that the State has met the basic
infrastructure requirements of section 110(a)(2). For example, in
response to the requirement to have enforceable emission limitations
under section 110(a)(2)(A), Colorado cited to rules in Regulation
Number 7 that were submitted to meet the reasonably available control
technology (RACT) requirements of part D. The EPA is approving those
rules as meeting the requirement to have enforceable emission
limitations on ozone precursors; any judgment about whether those
emission limitations discharge the State's obligation to impose RACT
under part D will be made separately, in an action reviewing those
rules pursuant to the requirements of part D. Colorado also referenced
other SIP provisions that are relevant, such as the motor vehicle
inspection and maintenance program in Regulation 11 and the State's
minor new source review (NSR) and Prevention of Significant
Deterioration (PSD) Programs in Regulation 3. We propose to find these
provisions adequately address the requirements of element (A), again
subject to the clarifications made in this document.
2. North Dakota
    The State's submission and the EPA's analysis:
    Multiple SIP-approved State air quality regulations within the NDAC
cited in North Dakota's certifications provide enforceable emission
limitations and other control measures, means or techniques, schedules
for compliance, and other related matters necessary to meet the
requirements of the CAA section 110(a)(2)(A) for the 2015 ozone NAAQS,
subject to the following clarification.
    The EPA does not consider the SIP requirements triggered by the
nonattainment area mandates in part D of Title 1 of the CAA to be
governed by the submission deadline of section 110(a)(1). Furthermore,
North Dakota has no areas designated as nonattainment for the 2015
ozone NAAQS. North Dakota's certifications (contained within this
docket) generally listed provisions within its SIP which regulate
pollutants through various

programs, including major or minor source permit programs. This
suffices, in the case of North Dakota, to meet the requirements of
section 110(a)(2)(A) for the 2015 ozone NAAQS.

B. CAA Section 110(a)(2)(B): Ambient Air Quality Monitoring/Data System

    Section 110(a)(2)(B) requires SIPs to provide for establishment and
operation of appropriate devices, methods, systems, and procedures
necessary to ``(i) monitor, compile, and analyze data on ambient air
quality, and (ii) upon request, make such data available to the
Administrator.''
1. Colorado
    (i) The State's submission:
    As discussed in Colorado's submission, the Colorado Air Pollution
Control Division (APCD) periodically submits a Quality Management Plan
and a Quality Assurance Project Plan to the EPA. These plans cover
procedures to monitor and analyze data. The provisions for episode
monitoring, data compilation and reporting, public availability of
information, and annual network reviews are found in the statewide
monitoring SIP (58 FR 49435, September 23, 1993). As part of the
monitoring SIP, Colorado submits an Annual Monitoring Network Plan
(AMNP) each year for the EPA's approval.
    (ii) The EPA's analysis:
    A comprehensive Annual Monitoring Network Plan (AMNP), intended to
fully meet the Federal requirements, was submitted to the EPA by
Colorado on June 29, 2018, and subsequently approved by the EPA. We
propose to find that Colorado's SIP and practices are adequate for the
ambient air quality monitoring and data system requirements for the
2015 ozone NAAQS; and therefore, propose to approve the infrastructure
SIP for the 2015 ozone NAAQS for this element.
2. North Dakota
    (i) The State's submission:
    North Dakota references NDCC 23.1-06-04.1.1 as the provision that
provides authority to conduct ambient air monitoring. Additionally,
North Dakota's SIP (45 FR 53475, August 12, 1980) provides for the
design and operation of its monitoring network, reporting of data
obtained from the monitors, and annual network review including
notification to the EPA of any changes, and public notification of
exceedances of NAAQS.
    (ii) The EPA's analysis:
    The comprehensive 2018 Annual Monitoring Network Plan (AMNP),
intended to fully meet Federal requirements, was submitted to the EPA
by North Dakota on October 31, 2018 and subsequently approved by the
EPA. In accordance with 40 CFR 58.10, beginning in July 2008, and every
five years thereafter, North Dakota develops a periodic network
assessment to ensure the effective implementation of an adequate
ambient air quality surveillance system. The plan includes statutory
and regulatory authority to establish and operate an air quality
monitoring network, including ozone monitoring.
    North Dakota's SIP-approved regulations provide for the design and
operation of its monitoring network, reporting of data obtained from
the monitors, and annual network review including notification to the
EPA of any changes, and public notification of exceedances of NAAQS. As
described in its submission, North Dakota operates a comprehensive
monitoring network, including ozone monitoring, compiles and analyzes
collected data, and submits the data to the EPA's Air Quality System on
a quarterly basis. Therefore, we are proposing to approve the North
Dakota SIP as meeting the requirements of CAA section 110(a)(2)(B) for
the 2015 ozone NAAQS.

C. CAA Section 110(a)(2)(C): Program for Enforcement of Control
Measures

    CAA section 110(a)(2)(C) requires each state to have a program that
provides for the following three sub-elements; enforcement, state-wide
regulation of new and modified minor sources and minor modifications of
major sources; and preconstruction permitting of major sources and
major modifications in areas designated attainment or unclassifiable
for the 2015 ozone NAAQS as required by CAA Title I part C (i.e., the
major source PSD program).
1. Colorado
    (i) The State's submission:
    The Colorado submission refers to the following SIP-approved Code
of Colorado Regulations (CCR) which address and provide for meeting all
requirements of CAA section 110(a)(2)(C):

 Regulation 1, Particulates, Smokes, Carbon Monoxide, and
Sulfur Dioxides
 Regulation 3, Stationary Source Permitting and Air Pollution
Emission Notice Requirements
 Regulation 4, Woodburning Controls
 Regulation 7, Control of Ozone via Ozone Precursors and
Nitrogen Oxides
 Regulation 11, Motor Vehicle Inspection
 Regulation 16, Street Sanding and Sweeping
 Common Provisions Regulation

    (ii) The EPA's analysis:
    With regard to the sub-element requirement of a program providing
for enforcement of all SIP measures, we are proposing to find that
Colorado's regulations provide broad authority to allow the State to
enforce applicable laws, regulations, and standards; to seek injunctive
relief; and to provide authority to prevent construction, modification,
or operation of any stationary source at any location where emissions
from such source will prevent the attainment or maintenance of a
national standard or interfere with PSD requirements. Many of the AQCC
regulations above address Colorado's program for enforcement of control
measures.\4\
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    \4\ We note also that, for element 110(a)(2)(E)(i), the state
cited 25-7-111, C.R.S., as providing the general authority for the
Division to enforce the SIP.
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    Turning to the second sub-element, regulation of new and modified
minor sources and minor modifications of major sources, Colorado has a
SIP-approved minor NSR program, adopted under section 110(a)(2)(C) of
the Act. The minor NSR program is found in Regulation 3 of the Colorado
SIP. The EPA originally approved Colorado's minor NSR program into the
SIP as Regulation 3 (68 FR 37744, June 25, 2003), and over the years,
the EPA has subsequently approved revisions to this program as
consistent with the CAA and Federal minor NSR requirements codified at
40 CFR 51.160 through 40 CFR 51.164. The State and the EPA have relied
on the State's existing minor NSR program to assure that new and
modified sources not captured by the major NSR permitting program do
not interfere with attainment and maintenance of the NAAQS. We propose
to determine that this program regulates construction of new and
modified minor sources of ozone precursors for purposes of the 2015
ozone NAAQS.
    Lastly, to generally meet the requirements of CAA section
110(a)(2)(C) with regard to the sub-element of preconstruction
permitting of major sources and major modifications in areas designated
attainment or unclassifiable for the subject NAAQS as required by CAA
Title I part C, a state is required to have PSD, NNSR, and minor NSR
permitting programs adequate to implement the 2015 ozone NAAQS. The EPA
interprets the CAA to require each state to make an infrastructure SIP
submission for a new or revised NAAQS that demonstrates

that the air agency has a complete PSD permitting program meeting the
current requirements for all regulated NSR pollutants. To meet this
requirement, Colorado cited its Colorado's SIP-approved PSD program
codified at 5 CCR 1001-5, known as Regulation 3. We most recently
approved revisions to Colorado's PSD (and NNSR) programs on May 3, 2019
(84 FR 18991). The EPA is proposing to approve Colorado's
infrastructure SIP for the 2015 ozone NAAQS with respect to the general
requirement in section 110(a)(2)(C) to include a PSD program in the SIP
that covers all regulated pollutants including greenhouse gases (GHGs).
    In addition to these requirements, there are four other revisions
to the Colorado SIP that are necessary to meet the requirements of
infrastructure element 110(a)(2)(C). These four revisions are related
to (1) the Ozone Implementation NSR Update (November 29, 2005, 70 FR
71612); (2) the ``Prevention of Significant Deterioration and Title V
Greenhouse Gas Tailoring Rule'' (June 3, 2010, 75 FR 31514); (3) the
NSR PM2.5 Rule (May 16, 2008, 73 FR 28321); and (4) the
final rulemaking entitled ``Prevention of Significant Deterioration
(PSD) for Particulate Matter Less Than 2.5 Micrometers
(PM2.5)--Increments, Significant Impact Levels (SILs) and
Significant Monitoring Concentration (SMC)'' (75 FR 64864, Oct. 20,
2010).
    On January 9, 2012 (77 FR 1027), we approved revisions to
Colorado's PSD program that addressed the PSD requirements of the Phase
2 Ozone Implementation Rule promulgated on November 29, 2005 (70 FR
71612). As a result, the approved Colorado PSD program meets the
current requirements for ozone.
    With respect to GHGs, on June 23, 2014, the United States Supreme
Court addressed the application of PSD permitting requirements to GHG
emissions. Utility Air Regulatory Group v. Environmental Protection
Agency, 134 S Ct. 2427 (2014). The Supreme Court held that the EPA may
not treat GHGs as an air pollutant for purposes of determining whether
a source is a major source required to obtain a PSD permit. The Court
also held that the EPA could continue to require that PSD permits,
otherwise required based on emissions of pollutants other than GHGs,
(anyway sources) \5\ contain limitations on GHG emissions based on the
application of Best Available Control Technology (BACT).
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    \5\ See 77 FR 41066 (July 12, 2012) (rulemaking for definition
of ``anyway'' sources).
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    In accordance with the Supreme Court decision, on April 10, 2015,
the U.S. Court of Appeals for the District of Columbia Circuit (the
D.C. Circuit) in Coalition for Responsible Regulation v. EPA, 606 F.
App'x. 6, at *7-8 (D.C. Cir. April 10, 2015), issued an amended
judgment vacating the regulations that implemented Step 2 of the EPA's
PSD and Title V Greenhouse Gas Tailoring Rule, but not the regulations
that implement Step 1 of that rule. Step 1 of the Tailoring Rule covers
sources that are required to obtain a PSD permit based on emissions of
pollutants other than GHGs. Step 2 applied to sources that emitted only
GHGs above the thresholds triggering the requirement to obtain a PSD
permit. The amended judgment preserves, without the need for additional
rulemaking by the EPA, the application of the BACT requirement to GHG
emissions from Step 1 or ``anyway sources.'' With respect to Step 2
sources, the D.C. Circuit's amended judgment vacated the regulations at
issue in the litigation, including 40 CFR 51.166(b)(48)(v), ``to the
extent they require a stationary source to obtain a PSD permit if
greenhouse gases are the only pollutant (i) that the source emits or
has the potential to emit above the applicable major source thresholds,
or (ii) for which there is a significant emission increase from a
modification.'' The EPA subsequently revised our PSD regulations to
remove the vacated provisions. 80 FR 50199 (Aug. 19, 2015).
    The EPA has subsequently revised our PSD regulations in response to
the Court's decision and the subsequent amended judgment by the U.S.
Court of Appeals for the District of Columbia Circuit (the D.C.
Circuit) in Coalition for Responsible Regulation v. EPA, 606 F. App'x.
6, at *7-8 (D.C. Cir. April 10, 2015). We recently approved revisions
to the Colorado PSD program that are consistent with our revised
regulations. See 84 FR 6732 (Feb. 28, 2019) (proposal); 84 FR 18991
(May 3, 2019) (final). Thus, Colorado's PSD program is current with
respect to regulation of GHGs.
    Finally, we evaluate the PSD program with respect to current
requirements for PM2.5. In particular, on May 16, 2008, the
EPA promulgated the rule, ``Implementation of the New Source Review
Program for Particulate Matter Less Than 2.5 Micrometers
(PM2.5)'' (73 FR 28321) and on October 20, 2010, the EPA
promulgated the rule, ``Prevention of Significant Deterioration (PSD)
for Particulate Matter Less Than 2.5 Micrometers (PM2.5)--
Increments, Significant Impact Levels (SILs) and Significant Monitoring
Concentration (SMC)'' (75 FR 64864). The EPA regards adoption of these
PM2.5 rules as a necessary requirement when assessing a PSD
program for the purposes of element (C).
    On January 4, 2013, the U.S. Court of Appeals, in Natural Resources
Defense Council v. EPA, 706 F.3d 428 (D.C. Cir.), remanded the EPA's
2007 and 2008 rules implementing the 1997 PM2.5 NAAQS. The
Court ordered the EPA to ``repromulgate these rules pursuant to Subpart
4 consistent with this opinion.'' Id. at 437. Subpart 4 of part D,
Title 1 of the CAA establishes additional provisions for PM
nonattainment areas.
    The 2008 implementation rule addressed by the court decision,
``Implementation of New Source Review (NSR) Program for Particulate
Matter Less Than 2.5 Micrometers (PM2.5)'' (73 FR 28321, May
16, 2008), promulgated NSR requirements for implementation of
PM2.5 in nonattainment areas (nonattainment NSR (NNSR)) and
attainment/unclassifiable areas (PSD). As the requirements of Subpart 4
only pertain to nonattainment areas, the EPA does not consider the
portions of the 2008 Implementation rule that address requirements for
PM2.5 attainment and unclassifiable areas to be affected by
the decision. Moreover, the EPA does not anticipate the need to revise
any PSD requirements promulgated in the 2008 Implementation rule in
order to comply with the court's decision. Accordingly, the EPA's
proposed approval of Colorado's infrastructure SIP for elements C or J
with respect to the PSD requirements promulgated by the 2008
Implementation rule does not conflict with the court's opinion.
    The court's decision with respect to the NNSR requirements
promulgated by the 2008 Implementation rule also does not affect the
EPA's action on the present infrastructure action. The EPA interprets
the Act to exclude nonattainment area requirements, including
requirements associated with a NNSR program, from infrastructure SIP
submissions due three years after adoption or revision of a NAAQS.
Instead, these elements are typically referred to as nonattainment SIP
or attainment plan elements, which would be due by the dates
statutorily prescribed under subpart 2 through 5 under part D,
extending as far as 10 years following designations for some elements.
    The second PSD requirement for PM2.5 is contained in the
EPA's October 20, 2010 rule, ``Prevention of Significant Deterioration
(PSD) for Particulate Matter Less Than 2.5 Micrometers
(PM2.5)--Increments, Significant Impact Levels (SILs) and
Significant Monitoring

Concentration (SMC)'' (75 FR 64864). The EPA regards adoption of the
PM2.5 increments as a necessary requirement when assessing a
PSD program for the purposes of element (C).
    On May 11, 2012, the State submitted revisions to Regulation 3 that
adopted all elements of the 2008 Implementation Rule and the 2010
PM2.5 Increment Rule. However, the submittal contained a
definition of Major Source Baseline Date which was inconsistent with 40
CFR 51.166(b)(14)(i). On May 13, 2013, the State submitted revisions to
Regulation 3 which incorporate the definition of Major Source Baseline
Date which was consistent with 40 CFR 51.166(b)(14)(i). These submitted
revisions make Colorado's PSD program up to date with respect to
current requirements for PM2.5. The EPA approved the
necessary portions of Colorado's May 11, 2012 and May 13, 2013
submissions which incorporate the requirements of the 2008
PM2.5 Implementation Rule and the 2010 PM2.5
Increment Rule on September 23, 2013 (78 FR 58186). Colorado's SIP-
approved PSD program meets current requirements for PM2.5.
    The EPA therefore is proposing to approve Colorado's SIP for the
2015 ozone NAAQS with respect to the requirement in section
110(a)(2)(C) to include a permit program in the SIP as required by part
C of the Act.
    The State has a SIP-approved minor NSR program, adopted under
section 110(a)(2)(C) of the Act. The minor NSR program is found in
Regulation 3 of the Colorado SIP, and was originally approved by the
EPA as Regulation 3 of the SIP (see 68 FR 37744, June 25, 2003). Since
approval of the minor NSR program, the State and the EPA have relied on
the program to ensure that new and modified sources not captured by the
major NSR permitting programs do not interfere with attainment and
maintenance of the NAAQS. Therefore, based on the foregoing, the EPA is
proposing to fully approve Colorado's infrastructure SIP for the 2015
ozone NAAQS with respect to the general requirement in section
110(a)(2)(C) to include a program in the SIP that regulates the
modification and construction of any stationary source as necessary to
assure that the NAAQS are achieved.
2. North Dakota
    (i) The State's submission:
    The North Dakota submission refers to the following state rules and
regulations which are also SIP-approved, that address and provide for
meeting all provisions and requirements of CAA section 110(a)(2)(C):

 NDCC 23.1-06-04.1
 NDCC 23.1-06-09
 NDCC 23.1-06-14
 NDAC 33.1-15-01-17
 NDAC 33.1-15-14-02
 NDAC 33.1-15-14-03
 NDAC 33.1-15-14-06
 NDAC 33.1-15-02
 NDAC 33.1-15-15

    (ii) The EPA's analysis:
    With regard to the sub-element requirement to have a program
providing for enforcement of all SIP measures, we concur with the State
that NDCC 23.1-06-14, Enforcement--Penalties--Injunctions provides the
authority for enforcement and specifies penalties for violations of all
North Dakota APCR (NDAPCR). Additionally, we find that NDAC 33.1-15-01-
17, Enforcement, (69 FR 61762, November 22, 2004) also provides a
general interpretation of enforcement for the NDAPCR, thus North Dakota
meets the first sub-element for enforcement for 110(a)(2)(C).
    Turning to the second sub-element of the state-wide regulation of
new and modified minor sources and minor modifications of major
sources, North Dakota has a SIP-approved minor NSR program. The minor
NSR program is found in NDAC 33.1-15-14-02, Permit to Construct; NDAC
33.1-15-14-03, Minor Source Permit to Operate; and NDAC 33.1-15-14-
06.1, Title V Permit to Operate. The EPA previously approved North
Dakota's minor NSR program into the SIP, with our most recent approved
revision occurring on October 21, 2016 (81 FR 72718). The EPA has
approved revisions to this program as consistent with the CAA and
Federal minor NSR requirements codified at 40 CFR 51.160 through 40 CFR
51.164. The State and the EPA have relied on the State's existing minor
NSR program to assure that new and modified sources not captured by the
major NSR permitting program do not interfere with attainment and
maintenance of the NAAQS. We propose to determine that this program
regulates construction of new and modified minor sources of ozone
precursors for purposes of the 2015 ozone NAAQS, thereby meeting the
second sub-element for regulation of minor sources and minor
modifications for 110(a)(2)(C).
    Lastly, to generally meet the requirements of CAA section
110(a)(2)(C) with regard to the sub-element of preconstruction
permitting of major sources and major modifications in areas designated
attainment or unclassifiable for the subject NAAQS as required by CAA
title I part C, a state is required to have PSD, NNSR, and minor NSR
permitting programs adequate to implement the 2015 ozone NAAQS.
    With respect to Elements (C) and (J), the EPA interprets the CAA to
require each state to make an infrastructure SIP submission for a new
or revised NAAQS demonstrating that the air agency has a complete PSD
permitting program meeting the current requirements for all regulated
NSR pollutants. The requirements of Element D(i)(II) prong 3 may also
be satisfied by demonstrating the air agency has a complete PSD
permitting program that applies to all regulated NSR pollutants. North
Dakota has shown that it currently has a PSD program in place that
covers all regulated NSR pollutants, including greenhouse gases (GHGs).
    On June 3, 2010 (75 FR 31291), we approved a revision to the North
Dakota PSD program that addressed the PSD requirements of the Phase 2
Ozone Implementation Rule promulgated on November 29, 2005 (70 FR
71612). We most recently approved revisions to North Dakota's PSD
program on October 21, 2016 (81 FR 72718). North Dakota's SIP approved
PSD program is codified in NDAC 33.1-15-15 and incorporates by
reference all Federal PSD regulations. As a result, the EPA-approved
North Dakota PSD program meets the current requirements for ozone.
    Similarly, on October 23, 2012 (77 FR 64736), we approved a North
Dakota SIP revision that revised the date of incorporation by reference
of the Federal PSD program to July 2, 2010. As explained in the notice
for that action, that revision addressed the PSD requirements related
to GHGs provided in the EPA's June 3, 2010 ``Prevention of Significant
Deterioration and Title V Greenhouse Gas Tailoring Rule'' (75 FR
31514). The approved North Dakota PSD program thus also meets current
requirements for GHGs.
    Based on the Supreme Court GHG decision discussion above, the EPA
has determined that North Dakota's SIP is sufficient to satisfy
Elements (C), (D)(i)(II) prong 3 and (J) with respect to GHGs. This is
due to the PSD permitting program previously approved by the EPA into
the SIP continues to require that PSD permits issued to ``anyway
sources'' contain limitations on GHG emissions based on the application
of BACT. The approved North Dakota PSD permitting program still
contains some provisions regarding Step 2 sources that are no longer
necessary in light of the Supreme Court decision and D.C. Circuit's
amended judgment. Nevertheless, the presence of these provisions in the
previously-approved

plan does not render the infrastructure SIP submission inadequate to
satisfy Elements (C), (D)(i)(II) prong 3 and (J). The SIP contains the
PSD requirements for applying the BACT requirement to greenhouse gas
emissions from ``anyway sources'' that are necessary at this time. The
application of those requirements is not impeded by the presence of
other previously-approved provisions regarding the permitting of Step 2
sources. Accordingly, the Supreme Court decision and subsequent D.C.
Circuit judgment do not prevent the EPA's approval of North Dakota's
infrastructure SIP as to the requirements of Elements (C), (D)(i)(II)
prong 3, and (J).
    Finally, we evaluate the PSD program with respect to current
requirements for PM2.5. Noting the PM2.5
discussion above the EPA's proposed approval of North Dakota's
infrastructure SIP as to Elements (C), (D)(i)(II) prong 3, and (J) with
respect to the PSD requirements promulgated by the 2008 Ozone
Implementation rule does not conflict with the court's opinion.
    The court's decision with respect to the NNSR requirements
promulgated by the 2008 Implementation Rule also does not affect the
EPA's action on the present infrastructure action. The EPA interprets
the Act to exclude nonattainment area requirements, including
requirements associated with a NNSR program, from infrastructure SIP
submissions due three years after adoption or revision of a NAAQS.
Instead, these elements are typically referred to as nonattainment SIP
or attainment plan elements, which would be due by the dates
statutorily prescribed under subpart 2 through 5 under part D,
extending as far as 10 years following designations for some elements.
    The second PSD requirement for PM2.5 is contained in the
EPA's October 20, 2010 rule, ``Prevention of Significant Deterioration
(PSD) for Particulate Matter Less Than 2.5 Micrometers
(PM2.5)--Increments, Significant Impact Levels (SILs) and
Significant Monitoring Concentration (SMC)'' (75 FR 64864). The EPA
regards adoption of the PM2.5 increments as a necessary
requirement when assessing a PSD program for the purposes of Element
(C).
    On October 23, 2012 (77 FR 64736), the EPA approved SIP revisions
that revised North Dakota's PSD program which incorporated the 2008
Implementation Rule. On July 30, 2013 (78 FR 45866), the EPA approved
revisions to the North Dakota SIP to reflect the 2010 PM2.5
Increment Rule. Therefore, North Dakota's SIP approved PSD program
meets current requirements for PM2.5.
    Therefore, the EPA is proposing to approve North Dakota's
infrastructure SIP for the 2015 ozone NAAQS with respect to the
requirement in section 110(a)(2)(C) to include a PSD permitting program
in the SIP that covers the requirements for all regulated NSR
pollutants as required by part C of the Act.
    The State has a SIP-approved minor NSR program, adopted under
section 110(a)(2)(C) of the Act, originally approved by the EPA on
August 21, 1995 (60 FR 43401). The minor NSR program is found in NDAC
33.1-15-14-02, Permit to Construct; NDAC 33.1-15-14-03, Minor Source
Permit to Operate; and NDAC 33.1-15-14-06, Title V Permit to Operate.
Since approval of the minor NSR program, the State and the EPA have
relied on the State's existing minor NSR program to assure that new and
modified sources not captured by the major NSR permitting program do
not interfere with attainment and maintenance of the NAAQS.
    Therefore, based on the foregoing, the EPA is proposing to approve
North Dakota's infrastructure SIP for the 2015 ozone NAAQS with respect
to the general requirement in section 110(a)(2)(C) to include a program
in the SIP that regulates the enforcement of control measures in the
SIP, and the modification and construction of any stationary source as
necessary to assure that the NAAQS are achieved.

D. CAA Section 110(a)(2)(D): Interstate Transport

    CAA section 110(a)(2)(D)(i) consists of four separate elements, or
``prongs.'' CAA section 110(a)(2)(D)(i)(I) requires SIPs to contain
adequate provisions prohibiting emissions which will contribute
significantly to nonattainment of the NAAQS in any other state (prong
1), and adequate provisions prohibiting emissions which will interfere
with maintenance of the NAAQS by any other state (prong 2). CAA section
110(a)(2)(D)(i)(II) requires SIPs to contain adequate provisions
prohibiting emissions which will interfere with any other state's
required measures to prevent significant deterioration of its air
quality (prong 3), and adequate provisions prohibiting emissions which
will interfere with any other state's required measures to protect
visibility (prong 4). Under section 110(a)(2)(D)(i)(I) of the CAA, the
EPA and states must give independent significance to prong 1 and prong
2 when evaluating downwind air quality problems under section
110(a)(2)(D)(i)(i)(I).\6\
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    \6\ See North Carolina v. EPA, 531 F.3d 896, 909-911 (2008).
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    With regard to the prong 1 and prong 2 requirements of CAA section
110(a)(2)(D)(i)(I), the EPA has addressed these requirements with
respect to prior ozone NAAQS in several regional regulatory actions,
including the Cross-State Air Pollution Rule (CSAPR), which addressed
interstate transport with respect to the 1997 ozone NAAQS as well as
the 1997 and 2006 fine PM standards, and the Cross-State Air Pollution
Rule Update for the 2008 ozone NAAQS (CSAPR Update).\7\ These actions
only addressed interstate transport in the Eastern United States \8\
and did not address the 2015 ozone NAAQS.
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    \7\ See 76 FR 48208 (August 8, 2011) (i.e., CSAPR) and 81 FR
74504 (October 26, 2016) (i.e., CSAPR Update).
    \8\ For purposes of the CSAPR and CSAPR Update actions, the
Western U.S. (or the West) was considered to consist of the 11
western contiguous states of Arizona, California, Colorado, Idaho,
Montana, Nevada, New Mexico, Oregon, Utah, Washington, and Wyoming.
The Eastern U.S. (or the East) was considered to consist of the 37
states east of the 11 Western states.
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    Through the development and implementation of CSAPR, the CSAPR
Update and previous regional rulemakings pursuant to the good neighbor
provision,\9\ the EPA, working in partnership with states, developed
the following four-step interstate transport framework to address the
requirements of the good neighbor provision for the ozone NAAQS: \10\
(1) Identify downwind air quality problems; (2) identify upwind states
that impact those downwind air quality problems sufficiently such that
they are considered ``linked'' and therefore warrant further review and
analysis; (3) identify the emissions reductions necessary (if any),
considering cost and air quality factors, to prevent linked upwind
states identified in step 2 from contributing significantly to
nonattainment or interfering with maintenance of the NAAQS at the
locations of the downwind air quality problems; and (4) adopt permanent
and enforceable measures needed to achieve those emissions reductions.
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    \9\ Other regional rulemakings addressing ozone transport
include the NOX SIP Call, 63 FR 57356 (October 27, 1998),
and the Clean Air Interstate Rule (CAIR), 70 FR 25162 (May 12,
2005).
    \10\ The four-step interstate framework has also been used to
address requirements of the good neighbor provision for some
previous particulate matter and ozone NAAQS, including in the
Western United States. See, e.g., 83 FR 30380 (June 28, 2018) and 83
FR 5375, 5376-77 (February 7, 2018).
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    The EPA has released several documents containing information
relevant to evaluating interstate

transport with respect to the 2015 ozone NAAQS. First, on January 6,
2017, the EPA published a notice of data availability (NODA) with
preliminary interstate ozone transport modeling with projected ozone
design values for 2023, on which we requested comment.\11\ The year
2023 was used as the analytic year for this preliminary modeling
because that year aligns with the expected attainment year for Moderate
ozone nonattainment areas.\12\ On October 27, 2017, we released a
memorandum (October 2017 Memo) containing updated modeling data for
2023, which incorporated changes made in response to comments on the
NODA.\13\ Although the October 2017 Memo released data for a 2023
modeling year, we specifically stated that the modeling may be useful
for states developing SIPs to address remaining good neighbor
obligations for the 2008 ozone NAAQS but did not address the 2015 ozone
NAAQS. And, on March 27, 2018, we issued a memorandum (March 2018 Memo)
indicating the same 2023 modeling data released in the October 2017
Memo could also be useful for evaluating potential downwind air quality
problems with respect to the 2015 ozone NAAQS (step 1 of the four-step
framework). The March 2018 Memo included newly available contribution
modeling results to assist states in evaluating their impact on
potential downwind air quality problems (step 2 of the four-step
framework) in their efforts to develop good neighbor SIPs for the 2015
ozone NAAQS to address their interstate transport obligations.\14\ The
EPA subsequently issued two more memoranda in August and October 2018,
providing guidance to states developing good neighbor SIPs for the 2015
NAAQS concerning, respectively, potential contribution thresholds that
may be appropriate to apply in step 2 and considerations for
identifying downwind areas that may have problems maintaining the
standard (under interstate transport prong 2) at step 1 of the
framework.\15\
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    \11\ See Notice of Availability of the Environmental Protection
Agency's Preliminary Interstate Ozone Transport Modeling Data for
the 2015 Ozone National Ambient Air Quality Standard (NAAQS), 82 FR
1733 (January 6, 2017).
    \12\ 82 FR 1735 (January 6, 2017).
    \13\ See Information on the Interstate Transport State
Implementation Plan Submissions for the 2008 Ozone National Ambient
Air Quality Standards under Clean Air Act Section
110(a)(2)(D)(i)(I), October 27, 2017, available in the docket for
this action or at https://www.epa.gov/interstate-air-pollution-transport/interstate-air-pollution-transport-memos-and-notices.
    \14\ See Information on the Interstate Transport State
Implementation Plan Submissions for the 2015 Ozone National Ambient
Air Quality Standards under Clean Air Act Section
110(a)(2)(D)(i)(I), March 27, 2018, available in the docket for this
action or at https://www.epa.gov/interstate-air-pollution-transport/interstate-air-pollution-transport-memos-and-notices.
    \15\ See Analysis of Contribution Thresholds for Use in Clean
Air Act Section 110(a)(2)(D)(i)(I) Interstate Transport State
Implementation Plan Submissions for the 2015 Ozone National Ambient
Air Quality Standards, August 31, 2018) (``August 2018
memorandum''), and Considerations for Identifying Maintenance
Receptors for Use in Clean Air Act Section 110(a)(2)(D)(i)(I)
Interstate Transport State Implementation Plan Submissions for the
2015 Ozone National Ambient Air Quality Standards, October 19, 2018,
available in the docket for this action or at https://www.epa.gov/airmarkets/memo-and-supplemental-information-regarding-interstate-transport-sips-2015-ozone-naaqs.
---------------------------------------------------------------------------

    The March 2018 Memo describes the process and results of the
updated photochemical and source-apportionment modeling used to project
ambient ozone concentrations for the year 2023 and the state-by state
impacts on those concentrations. The March 2018 Memo also explains that
the selection of the 2023 analytic year aligns with the 2015 NAAQS
attainment year for Moderate nonattainment areas. As described in more
detail in the October 2017 and March 2018 memoranda, the EPA used the
Comprehensive Air Quality Model with Extensions (CAMx version 6.40) to
model average and maximum design values in 2023 to identify potential
nonattainment and maintenance receptors (i.e., monitoring sites that
are projected to have problems attaining or maintaining the 2015 ozone
NAAQS). The March 2018 Memo presents design values calculated in two
ways: First, following the EPA's historic ``3 x 3'' approach\16\ to
evaluating all sites, and second, following a modified approach for
coastal monitoring sites in which ``overwater'' modeling data were not
included in the calculation of future year design values (referred to
as the ``no water'' approach).
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    \16\ See March 2018 Memo, at 4.
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    For purposes of identifying potential nonattainment and maintenance
receptors in 2023, the EPA applied the same approach used in the CSAPR
Update, wherein the EPA considered a combination of monitoring data and
modeling projections to identify monitoring sites that are projected to
have problems attaining or maintaining the NAAQS. Specifically, the EPA
identified nonattainment receptors as those monitoring sites with
measured values \17\ exceeding the NAAQS that also have projected
(i.e., in 2023) average design values exceeding the NAAQS. The EPA
identified maintenance receptors as those monitoring sites with
projected maximum design values exceeding the NAAQS. This included
sites with measured values below the NAAQS but with projected average
and maximum design values exceeding the NAAQS, and monitoring sites
with projected average design values below the NAAQS but with projected
maximum design values exceeding the NAAQS. The EPA included the design
values and monitoring data for all monitoring sites projected to be
potential nonattainment or maintenance receptors based on the updated
2023 modeling in Attachment B to the March 2018 Memo.
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    \17\ The EPA used 2016 ozone design values, based on 2014-2016
measured data, which were the most current data at the time of the
analysis. See attachment B of the March 2018 Memo, at B-1.
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    After identifying potential downwind nonattainment and maintenance
receptors, the EPA next performed nationwide, state-level ozone source-
apportionment modeling to estimate the expected impact from each state
to each nonattainment and maintenance receptor.\18\ The EPA included
contribution information resulting from the source-apportionment
modeling in Attachment C to the March 2018 Memo. For more specific
information on the modeling and analysis, please see the 2017 and March
2018 memoranda, the NODA for the preliminary interstate transport
assessment, and the supporting technical documents included in the
docket for this action.
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    \18\ As discussed in the March 2018 Memo, the EPA performed
source-apportionment model runs for a modeling domain that covers
the 48 contiguous United States and the District of Columbia, and
adjacent portions of Canada and Mexico.
---------------------------------------------------------------------------

    In the CSAPR and the CSAPR Update, the EPA used a threshold of one
percent of the NAAQS to determine whether a given upwind state was
``linked'' at step 2 of the four-step framework and would therefore
contribute to downwind nonattainment and maintenance sites identified
in step 1. If a state's impact did not equal or exceed the one percent
threshold, the upwind state was not ``linked'' to a downwind air
quality problem, and the EPA therefore concluded the state will not
significantly contribute to nonattainment or interfere with maintenance
of the NAAQS in the downwind states. However, if a state's impact
equaled or exceeded the one percent threshold, the state's emissions
were further evaluated in step 3, taking into account both air quality
and cost considerations, to determine what, if any, emissions
reductions might be necessary to address the good neighbor provision.
    As noted previously, on August 31, 2018, the EPA issued a
memorandum (August 2018 Memo) providing guidance concerning potential

contribution thresholds that may be appropriate to apply with respect
to the 2015 NAAQS in step 2. Consistent with the process for selecting
the one percent threshold in CSAPR and the CSAPR Update, the August
2018 Memo included analytical information regarding the degree to which
potential air quality thresholds would capture the collective amount of
upwind contribution from upwind states to downwind receptors for the
2015 ozone NAAQS. The August 2018 Memo indicated that, based on the
EPA's analysis of its most recent modeling data, the amount of upwind
collective contribution captured using a 1 ppb threshold is generally
comparable, overall, to the amount captured using a threshold
equivalent to one percent of the 2015 ozone NAAQS. Accordingly, the EPA
indicated that it may be reasonable and appropriate for states to use a
1 ppb contribution threshold, as an alternative to the one percent
threshold, at step 2 of the four-step framework in developing their SIP
revisions addressing the good neighbor provision for the 2015 ozone
NAAQS.\19\
---------------------------------------------------------------------------

    \19\ See August 2018 Memo, at 4.
---------------------------------------------------------------------------

    While the March 2018 Memo presented information regarding the EPA's
latest analysis of ozone transport following the approaches the EPA has
taken in prior regional rulemaking actions, the EPA has not made any
final determinations regarding how states should identify downwind
receptors with respect to the 2015 ozone NAAQS at step 1 of the four-
step framework. Rather, the EPA noted that states have flexibility in
developing their own SIPs to follow different analytical approaches
than the EPA's, so long as their chosen approach has an adequate
technical justification and is consistent with the requirements of the
CAA.
    The prong 3 (PSD) requirement of CAA section 110(a)(2)(D)(II) may
be met for all NAAQS by a state's confirmation in an infrastructure SIP
submission that new major sources and major modifications in the state
are subject to a comprehensive EPA-approved PSD permitting program in
the SIP that applies to all regulated NSR pollutants and that satisfies
the requirements of the EPA's PSD implementation rule(s).\20\
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    \20\ See 2013 Memo.
---------------------------------------------------------------------------

    To meet the prong 4 (visibility) requirement of CAA section
110(a)(2)(D)(i)(II) under the 2015 ozone NAAQS, a SIP must address the
potential for interference with visibility protection caused by ozone,
including precursors. An approved regional haze SIP that fully meets
the regional haze requirements in 40 CFR 51.308 satisfies the
110(a)(2)(D)(i)(II) requirement for visibility protection as it ensures
that emissions from the state will not interfere with measures required
to be included in other state SIPs to protect visibility. In the
absence of a fully approved regional haze SIP, a state can still make a
demonstration that satisfies the visibility requirement section of
110(a)(2)(D)(i)(II).\21\
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    \21\ See 2013 Memo. In addition, the EPA approved the visibility
requirement of 110(a)(2)(D)(i) for the 1997 Ozone and
PM2.5 NAAQS for Colorado before taking action on the
State's regional haze SIP. 76 FR 22036 (April 20, 2011).
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    CAA section 110(a)(2)(D)(ii) requires SIPs to include provisions
ensuring compliance with the applicable requirements of CAA sections
126 and 115 (relating to interstate and international pollution
abatement). CAA section 126 requires notification to neighboring states
of potential impacts from a new or modified major stationary source and
specifies how a State may petition the EPA when a major source or group
of stationary sources in a state is thought to contribute to certain
pollution problems in another state. CAA section 115 governs the
process for addressing air pollutants emitted in the United States that
cause or contribute to air pollution that may reasonably be anticipated
to endanger public health or welfare in a foreign country.
1. Colorado
    (i) The State's submission:
    Colorado's September 17, 2018 submission includes an interstate
transport analysis for prongs 1 and 2 that focused on the modeling
information provided in the EPA's March 2018 Memo. The State notes that
its highest projected ozone contribution to any nonattainment or
maintenance receptor outside of Colorado was 0.33 ppb at site ID
484392003 in Tarrant, TX. Colorado concludes that the modeling results
from the March 2018 Memo indicate that Colorado sources do not
contribute significantly to nonattainment or interfere with maintenance
of the 2015 ozone NAAQS in any other state.
    To address prong 3, Colorado references the PSD program in AQCC
Regulation Number 3 of the Colorado SIP, which the State asserts meets
all Federal requirements and applies to all regulated pollutants.
Colorado's submission states that it cannot issue a PSD permit unless
the new or modified source demonstrates that emissions from the
construction or operation of the facility will not cause or contribute
to air pollution in any area that exceeds any NAAQS. Colorado also
asserts that it cannot issue a NNSR permit unless the source shows it
has obtained sufficient emissions reductions to offset increases in
emissions of the pollutants for which an area is in nonattainment,
consistent with reasonable further progress toward attainment. For
these reasons, Colorado concludes that its SIP is sufficient to meet
the prong 3 requirements of CAA section 110(a)(2)(D)(i)(II).
    To address prong 4, Colorado references its EPA-approved Regional
Haze SIP to demonstrate that the state does not interfere with
visibility for the 2015 ozone NAAQS in any other state (77 FR 76871,
December 31, 2012).
    To address CAA section 110(a)(2)(D)(ii), Colorado states that there
are no petitions or pending actions before the EPA under sections 115,
126(b) and 126(c) of the CAA regarding interstate or international
transport. Colorado also states that its approved NSR program has a
regulatory provision in place that requires notification of neighboring
states of potential impacts from sources, specifically, AQCC Regulation
Number 3, Part D, Section IV, provides for notice to any state, tribal
governing body, Federal land manager (FLM) or local agency that may be
affected by emissions from a major source or major modification subject
to the PSD program. For these reasons, Colorado asserts that its SIP
meets the requirements of CAA section 110(a)(2)(D)(ii) for the 2015
ozone NAAQS.
    (ii) The EPA's Analysis:
Prongs 1 and 2: Significant Contribution to Nonattainment and
Interference With Maintenance
    The EPA primarily relied on the air quality results presented in
our March 2018 Memo for our analysis of prongs 1 and 2 for Colorado. As
previously discussed, the March 2018 Memo identifies potential downwind
nonattainment and maintenance receptors, using the definitions applied
in the CSAPR Update and using both the ``3 x 3'' and the ``no water''
approaches to calculating future year design values. The March 2018
memorandum identifies 75 potential nonattainment and maintenance
receptors in the contiguous U.S.\22\ The

March 2018 memorandum also provides contribution data regarding the
impact of other states on the potential receptors. For purposes of
evaluating Colorado's 2015 ozone NAAQS interstate transport SIP
submission, we propose that, at least where a state's impacts are less
than one percent to downwind nonattainment and maintenance sites, it is
reasonable to conclude that the state's impact will not significantly
contribute to nonattainment or interfere with maintenance of the NAAQS
in any other state. This is consistent with our prior action on
Colorado's SIP with respect to the 2008 ozone NAAQS \23\ and with the
EPA's approach to both the 1997 and 2008 ozone NAAQS in CSAPR and the
CSAPR Update. The EPA notes, nonetheless, that consistent with the
August 2018 memorandum, it may be reasonable and appropriate for states
to use a 1 ppb contribution threshold, as an alternative to a one
percent threshold, at step 2 of the four-step framework in developing
their SIP revisions addressing the good neighbor provision for the 2015
ozone NAAQS. However, for the reasons discussed below, it is
unnecessary for the EPA to determine whether it may be appropriate to
apply a 1 ppb threshold for purposes of this action.
---------------------------------------------------------------------------

    \22\ The number of receptors in the contiguous United states is
75. Of these, 73 are projected as nonattainment and/or maintenance
receptors in 2023 irrespective of whether the ``3 x 3'' or ``no
water'' approach is used. Two receptors, located in Richmond County,
New York and Milwaukee County, Wisconsin, respectively, are
projected as nonattainment and maintenance under one approach, but
are projected as neither nonattainment nor maintenance under the
second approach. Although the EPA has indicated that states may have
flexibilities to apply a different analytic approach to evaluating
interstate transport, including identifying downwind air quality
problems, because the EPA is also proposing in this action that
Colorado will have an insignificant impact on any potential
receptors identified in its analysis, Colorado need not definitively
determine whether the identified monitoring sites should be treated
as receptors for the 2015 ozone standard.
    \23\ 81 FR 7706 (February 16, 2016).
---------------------------------------------------------------------------

    The EPA's updated 2023 modeling discussed in the March 2018 Memo
indicates that Colorado's largest impact on any potential downwind
nonattainment and maintenance receptor in the United States are 0.33
ppb and 0.27 ppb, respectively.\24\ These values are less than 0.70 ppb
(one percent of the 2015 ozone NAAQS),\25\ demonstrating that emissions
from Colorado are not linked to any 2023 downwind potential
nonattainment and maintenance receptors identified in the March 2018
Memo. Thus, Colorado will not impact downwind air quality problems at a
level that warrants further review and analysis at step 2 of the 4-step
interstate transport framework. Accordingly, we propose to conclude
that emissions from Colorado will not contribute to any potential
receptors, and thus, will not significantly contribute to nonattainment
or interfere with maintenance of the NAAQS in any other state.
---------------------------------------------------------------------------

    \24\ The EPA's analysis indicates that Colorado will have a 0.33
ppb impact at the potential nonattainment receptor in Tarrant
County, Texas (Site ID 484392003), which has a 2023 projected
average design value of 74.8 ppb, a 2023 projected maximum design
value of 72.5 ppb, and had a 2014-2016 design value of 73 ppb. The
EPA's analysis further indicates that Colorado will have a 0.27 ppb
impact at a potential maintenance receptor in Denton County, Texas
(Site ID 481210034), which has which has a projected 2023 average
design value of 72 ppb, a 2023 projected maximum design value of
69.7 ppb, and had a 2014-2016 design value of 80 ppb. See the March
2018 Memo, attachment C.
    \25\ Because none of Colorado's impacts exceed 0.70 ppb, they
necessarily also do not exceed the 1 ppb contribution threshold
discussed in the August 2018 memorandum.
---------------------------------------------------------------------------

    We also note that the EPA has assessed potential transport to the
Shoshone-Bannock Tribes of the Fort Hall Reservation in southeast
Idaho, which the EPA approved to be treated as an affected downwind
state for CAA sections 110(a)(2)(D) and 126. While the Shoshone-Bannock
Tribes do not operate an ozone monitor, the nearest ozone monitors to
the Fort Hall Reservation are in Ada County, Idaho, in the Boise area
and in Butte County, Idaho, in the Idaho Falls area. As discussed
previously, the EPA's modeling did not identify receptors in Idaho and
the ozone monitoring sites nearest to the Fort Hall Reservation were
projected to remain below the current standard. For the Idaho Falls
area monitoring site (Site ID 160230101), which had a 2014-2016 design
value of 60 ppb, the EPA's modeling projects a 2023 maximum design
value of 60.2 ppb and a 2023 average design value of 59.6 ppb, both
below the 70 ppb standard. For the Boise area monitoring site with the
highest projected ozone concentrations (Site ID 160010017), which had a
2014-2016 design value of 67 ppb, the EPA's modeling projects a 2023
maximum design value of 59.8 ppb and a 2023 average design value of
59.4 ppb.\26\ We therefore propose to find that emissions from Colorado
will not significantly contribute to nonattainment or interfere with
maintenance of the 2015 ozone NAAQS at the Fort Hall Reservation.
---------------------------------------------------------------------------

    \26\ In attachment A of the October 2017 Memo, the EPA provided
the projected ozone design values at individual monitoring sites
nationwide. The data for the Idaho monitors is presented on page A-
10.
---------------------------------------------------------------------------

Prong 3: Interference With PSD Measures
    As noted, the PSD portion of section 110(a)(2)(D)(i)(II) may be met
by a state's confirmation in an infrastructure SIP submission that new
major sources and major modifications in the state are subject to a
comprehensive EPA-approved PSD permitting program in the SIP that
applies to all regulated NSR pollutants and that satisfies the
requirements of the EPA's PSD implementation rule(s).\27\ As noted in
Section III.(c)(1) of this proposed action, Colorado has such a
program, and the EPA is therefore proposing to approve Colorado's SIP
for the 2015 ozone NAAQS with respect to the requirement in section
110(a)(2)(C) to include a permit program in the SIP as required by part
C of the Act.
---------------------------------------------------------------------------

    \27\ See September 2013 Guidance at 31.
---------------------------------------------------------------------------

    As stated in the 2013 Memo, in-state sources not subject to PSD for
any one or more of the pollutants subject to regulation under the CAA
because they are in a nonattainment area for a NAAQS related to those
particular pollutants may also have the potential to interfere with PSD
in an attainment or unclassifiable area of another state. One way a
state may satisfy prong 3 with respect to these sources is by citing
EPA-approved NNSR provisions addressing any pollutants for which the
state has designated nonattainment areas. Colorado has a SIP-approved
NNSR program that ensures regulation of major sources and major
modifications in nonattainment areas.\28\
---------------------------------------------------------------------------

    \28\ See Colorado Regulation No. 3, Part D, Section V, which was
most recently approved by the EPA in a final rulemaking dated May 3,
2019 (84 FR 18991).
---------------------------------------------------------------------------

    As Colorado's SIP meets PSD requirements for all regulated NSR
pollutants, and contains a fully approved NNSR program, the EPA is
proposing to approve the infrastructure SIP submission as meeting the
applicable requirements of prong 3 of section 110(a)(2)(D)(i) for the
2015 ozone NAAQS.
Prong 4: Interference With Measures To Protect Visibility
    In our prong 4 review, the EPA primarily reviewed Colorado's
regional haze SIP. Colorado submitted a regional haze SIP to the EPA on
May 25, 2011. The EPA approved Colorado's regional haze SIP on December
31, 2012 (77 FR 76871). Colorado submitted an updated regional haze SIP
to the EPA on May 26, 2017, to incorporate an updated Best Available
Retrofit Technology (BART) limit for Craig Unit 1 and an updated
reasonable progress determination to incorporate a new limit for the
Nucla Station. The EPA approved these updates to the Colorado regional
haze SIP in a final action published July 5, 2018 (83 FR 31332).
Because Colorado has a fully approved regional haze SIP, we are
proposing to approve the Colorado SIP as meeting the requirements of
element 4 of CAA section 110(a)(2)(D)(i) for the 2015 ozone NAAQS.

110(a)(2)(D)(ii): Interstate and International Transport Provisions
    Regarding CAA section 110(a)(2)(D)(ii), Colorado's SIP approved PSD
program requires notice to states whose lands may be affected by the
emissions of sources subject to PSD, as required by 40 CFR
51.166(q)(2)(iv).\29\ This suffices to meet the notice requirement of
section 126(a). Colorado also has no pending obligations under sections
126(c) or 115(b). Therefore, the Colorado SIP currently meets the
requirements of those sections. In summary, the SIP satisfies the
requirements of CAA section 110(a)(2)(D)(ii) for the 2015 ozone NAAQS.
---------------------------------------------------------------------------

    \29\ See Colorado AQCC Regulation Number 3, Part D. IV.A.1.
---------------------------------------------------------------------------

2. North Dakota
    (i) The State's submission:
    In its November 6, 2018 submission, North Dakota's transport
analysis for prongs 1 and 2 focused on the modeling information
provided in the EPA's March 2018 Memo. North Dakota notes that the
maximum concentration of ozone that North Dakota sources are projected
to contribute to any nonattainment or maintenance receptor in the March
2018 Memo is 0.23 ppb, substantially less than the one percent
significant contribution level. North Dakota also states that it
reviewed the modeled emissions inventory from the March 2018 Memo and
determined that the 2011 base emissions inventory is correct, and the
2023 projected emissions are reasonable. For these reasons, North
Dakota concludes that sources in its state do not significantly
contribute to nonattainment or interfere with maintenance of the 2015
ozone NAAQS in any other state.
    To address prong 3, North Dakota asserts that new major sources and
modifications of existing major sources are subject to review for all
regulated NSR pollutants in accordance with North Dakota's EPA-approved
PSD program in the SIP. Specifically, North Dakota references its
incorporation by reference of the Federal PSD program into the North
Dakota SIP at 33.1-15-15, which it has incorporated through July 1,
2018. North Dakota notes that these rules incorporate all existing
requirements for ozone.
    To address prong 4, North Dakota points to existing portions in the
North Dakota SIP to certify that the State meets the visibility
requirements of section 110(a)(2)(D)(i). North Dakota specifically
references the North Dakota regional haze SIP as well as the EPA's
regional haze FIP, asserting that together the SIP and FIP provide all
measures necessary to achieve North Dakota's fair share of emissions
reductions based on that regional process.\30\ The State also
references the PSD (NDAC 33-15-15.1) and Visibility Protection (NDAC
33-15-19.1) portions of its SIP, both of which address visibility
impairment. North Dakota's submission also included analysis of
regional haze 5-year progress reports for Federal Class I areas in
neighboring states to which North Dakota was initially modeled to
significantly contribute to visibility impairment.\31\ North Dakota
asserts that these Class I areas are either meeting their reasonable
progress goals or, in the case of Medicine Lake in Montana, is not
meeting its reasonable progress goals due to international sources
rather than sources in North Dakota. North Dakota concludes that its
sources are making reasonable progress in remedying visibility
impairment in North Dakota's Class I areas and are not interfering with
other states plans for visibility improvement in their Class I areas,
and therefore the state meets the requirements of CAA section
110(a)(2)(D)(i)(II), prong 4, for the 2015 ozone NAAQS.
---------------------------------------------------------------------------

    \30\ See 77 FR 20894, April 6, 2012, and 78 FR 16452, March 15,
2013.
    \31\ The Five-Year Progress Reports that North Dakota included
in its analysis, for South Dakota (see https://denr.sd.gov/des/aq/aqnews/RH5YearReport.pdf), Montana (see https://deq.mt.gov/Portals/112/Public/Air/ProgressReport_DRAFT_7-2017.pdf), and Minnesota (see
https://www.pca.state.mn.us/sites/default/files/aq-sip2-17.pdf),
respectively, are all available in the docket for this proposed
action.
---------------------------------------------------------------------------

    To address CAA section 110(a)(2)(D)(ii), North Dakota states that
provisions in the PSD portion of its SIP, specifically NDAC-33.1-15-15-
01.2.1(q)(2)(d), require notification of neighboring states whose land
may be significantly affected by emissions from a new or modified
source in North Dakota. North Dakota also states that no sources within
North Dakota are the subject of an active finding under CAA section 126
with respect to any pollutant, and that there are no findings under CAA
section 115 against North Dakota with respect to any pollutant. For
these reasons, North Dakota concludes that its SIP meets the
requirements of CAA section 110(a)(2)(D)(ii).
    (ii) The EPA's analysis:
Prongs 1 and 2: Significant Contribution to Nonattainment and
Interference With Maintenance
    The EPA primarily relied on the air quality results presented in
our March 2018 Memo for our analysis of prongs 1 and 2 for North
Dakota. As previously discussed, the March 2018 Memo identifies
potential downwind nonattainment and maintenance receptors, using the
definitions applied in the CSAPR Update and using both the ``3 x 3''
and the ``no water'' approaches to calculating future year design
values. The March 2018 memorandum identifies 75 potential nonattainment
and maintenance receptors in the contiguous U.S. The March 2018
memorandum also provides contribution data regarding the impact of
other states on the potential receptors. For purposes of evaluating
North Dakota's 2015 ozone NAAQS infrastructure SIP submission, we
propose that, at least where a state's impacts are less than one
percent to downwind nonattainment and maintenance sites, it is
reasonable to conclude that the state's impact will not significantly
contribute to nonattainment or interfere with maintenance of the NAAQS
in any other state. This is consistent with our prior action on North
Dakota's SIP with respect to the 2008 ozone NAAQS \32\ and with the
EPA's approach to both the 1997 and 2008 ozone NAAQS in CSAPR and the
CSAPR Update. The EPA notes, nonetheless, that consistent with the
August 2018 memorandum, it may be reasonable and appropriate for states
to use a 1 ppb contribution threshold, as an alternative to a one
percent threshold, at step 2 of the four-step framework in developing
their SIP revisions addressing the good neighbor provision for the 2015
ozone NAAQS. However, for the reasons discussed below, it is
unnecessary for the EPA to determine whether it may be appropriate to
apply a 1 ppb threshold for purposes of this action.
---------------------------------------------------------------------------

    \32\ 81 FR 7706 (February 16, 2016).
---------------------------------------------------------------------------

    The EPA's updated 2023 modeling discussed in the March 2018 Memo
indicates that North Dakota's largest impact on any potential downwind
nonattainment and maintenance receptor in the United States are 0.23
ppb and 0.15 ppb, respectively.\33\ These values are less than 0.70 ppb
(one

percent of the 2015 ozone NAAQS),\34\ and as a result, demonstrate that
emissions from North Dakota are not linked to any 2023 downwind
potential nonattainment and maintenance receptors identified in the
March 2018 Memo. Accordingly, we propose to conclude that emissions
from North Dakota will not contribute to any potential receptors, and
thus, the state will not significantly contribute to nonattainment or
interfere with maintenance of the NAAQS in any other state.
---------------------------------------------------------------------------

    \33\ The EPA's analysis indicates that North Dakota will have a
0.23 ppb impact at the potential nonattainment receptor in Milwaukee
County, Wisconsin (Site ID 550790085). The Milwaukee County site has
a 2023 projected average design value of 73 ppb, a 2023 projected
maximum design value of 71.2 ppb, and had a 2014-2016 design value
of 71 ppb. The EPA's analysis further indicates that North Dakota
will have a 0.15 ppb impact at a potential maintenance receptor in
New Haven County, Connecticut (Site ID 90099002), which has which
has a projected 2023 average design value of 72.6 ppb, a 2023
projected maximum design value of 69.9 ppb, and had a 2014-2016
design value of 76 ppb. See the March 2018 Memo, attachment C.
    \34\ Because none of North Dakota's impacts exceed 0.70 ppb,
they necessarily also do not exceed the 1 ppb contribution threshold
discussed in the August 2018 memorandum.
---------------------------------------------------------------------------

    We also note that the EPA has assessed potential transport to the
Shoshone-Bannock Tribes of the Fort Hall Reservation in southeast
Idaho, which the EPA approved to be treated as an affected downwind
state for CAA sections 110(a)(2)(D) and 126. While the Shoshone-Bannock
Tribes do not operate an ozone monitor, the nearest ozone monitors to
the Fort Hall Reservation are in Ada County, Idaho, in the Boise area
and in Butte County, Idaho, in the Idaho Falls area. As discussed
previously, the EPA's modeling did not identify receptors in Idaho and
the ozone monitoring sites nearest to the Fort Hall Reservation were
projected to remain below the current standard. For the Idaho Falls
area monitoring site (Site ID 160230101), which had a 2014-2016 design
value of 60 ppb, the EPA's modeling projects a 2023 maximum design
value of 60.2 ppb and a 2023 average design value of 59.6 ppb, both
below the 70 ppb standard. For the Boise area monitoring site with the
highest projected ozone concentrations (Site ID 160010017), which had a
2014-2016 design value of 67 ppb, the EPA's modeling projects a 2023
maximum design value of 59.8 ppb and a 2023 average design value of
59.4 ppb.\35\ We therefore propose to find that emissions from North
Dakota will not significantly contribute to nonattainment or interfere
with maintenance of the 2015 ozone NAAQS at the Fort Hall Reservation.
---------------------------------------------------------------------------

    \35\ In attachment A of the October 2017 Memo, the EPA provided
the projected ozone design values at individual monitoring sites
nationwide. The data for the Idaho monitors is presented on page A-
10.
---------------------------------------------------------------------------

Prong 3: Interference With PSD Measures
    As noted, the PSD portion of section 110(a)(2)(D)(i)(II) may be met
by a state's confirmation in an infrastructure SIP submission that new
major sources and major modifications in the state are subject to a
comprehensive EPA-approved PSD permitting program in the SIP that
applies to all regulated NSR pollutants and that satisfies the
requirements of the EPA's PSD implementation rule(s).\36\ As noted in
Section III.(c)(2) of this proposed action, North Dakota has such a
program, and the EPA is therefore proposing to approve North Dakota's
SIP for the 2015 ozone NAAQS with respect to the requirement in section
110(a)(2)(C) to include a permit program in the SIP as required by part
C of the Act.
---------------------------------------------------------------------------

    \36\ See September 2013 Guidance at 31.
---------------------------------------------------------------------------

    As stated in the 2013 Memo, in-state sources not subject to PSD for
any one or more of the pollutants subject to regulation under the CAA
because they are in a nonattainment area for a NAAQS related to those
particular pollutants may also have the potential to interfere with PSD
in an attainment or unclassifiable area of another state. North Dakota
does not contain any nonattainment areas. The consideration of NNSR for
prong 3 is therefore not relevant as all major sources locating in the
state are subject to PSD. As North Dakota's SIP meets PSD requirements
for all regulated NSR pollutants, and North Dakota does not contain any
nonattainment areas, the EPA is proposing to approve the infrastructure
SIP submission as meeting the applicable requirements of prong 3 of
section 110(a)(2)(D)(i) for the 2015 ozone NAAQS.
Prong 4: Interference With Measures To Protect Visibility
    For the EPA's prong 4 analysis for North Dakota, the EPA reviewed
several pieces of information including the North Dakota regional haze
SIP and FIP. The 2013 Memo lays out two ways in which a state's
infrastructure SIP submittal may satisfy prong 4. One way is through a
state's confirmation in its infrastructure SIP submittal that it has an
EPA-approved regional haze SIP in place. Alternatively, in the absence
of a fully approved regional haze SIP, a state can make a demonstration
in its infrastructure SIP submittal that emissions within its
jurisdiction do not interfere with other states' plans to protect
visibility. Such a submittal should point to measures in the SIP that
limit visibility-impairing pollutants and ensure that the resulting
reductions conform to any mutually agreed emission reductions under the
relevant regional haze regional planning organization (RPO)
process.\37\
---------------------------------------------------------------------------

    \37\ See id. at 34, and also 76 FR 22036 (April 20, 2011)
containing the EPA's approval of the visibility requirement of
110(a)(2)(D)(i)(II) based on a demonstration by Colorado that did
not rely on the Colorado Regional Haze SIP.
---------------------------------------------------------------------------

    North Dakota worked through its RPO, the Western Regional Air
Partnership (WRAP), to develop strategies to address regional haze. To
help states in establishing reasonable progress goals for improving
visibility in Class I areas, the WRAP modeled future visibility
conditions based on the mutually agreed emissions reductions from each
state. The WRAP states then relied on this modeling in setting their
respective reasonable progress goals. As a result, we consider
emissions reductions from measures in North Dakota's SIP that conform
with the level of emission reductions the State agreed to include in
the WRAP modeling to meet the visibility requirement of CAA section
110(a)(2)(D)(i)(II).
    In this action, we are proposing to disapprove North Dakota's prong
4 infrastructure SIP submittal for the 2015 ozone NAAQS. The EPA's
disapproval of the North Dakota regional haze SIP included the specific
disapprovals of North Dakota's selection of nitrogen oxides
(NOX) BART for Great River Energy's Coal Creek Station and
the state's reasonable progress determination for Basin Electric's
Antelope Valley Station (77 FR 20894, April 6, 2012). Based on the
EPA's disapproval of these portions of North Dakota's regional haze
SIP, we propose to determine that North Dakota's SIP does not include
measures needed to ensure that its emissions will not interfere with
other states' plans to protect visibility from the effects of NAAQS
pollutants impacted by NOX. Specifically, NOX is
a precursor of ozone, and is also a term which refers to both nitrogen
oxide (NO) and nitrogen dioxide (NO2). The EPA is therefore
proposing to disapprove prong 4 of North Dakota's infrastructure SIP
with regard to the 2015 ozone NAAQS.
    If the EPA disapproves an infrastructure SIP submission for prong
4, as we are proposing, a FIP obligation will be created. However, the
EPA was previously under an obligation to promulgate a FIP for North
Dakota that corrects all regional haze SIP deficiencies (77 FR 20894,
April 6, 2012). Therefore, there will be no additional practical
consequences from the disapproval for the State, the sources within its
jurisdiction, or the EPA, as this disapproval will not add any new FIP
obligation for the EPA (See 2013 Memo at 34-35). Additionally, since
the infrastructure SIP submission is not required under CAA title I
part D or in response to a SIP call under CAA section 110(k)(5),
mandatory sanctions under CAA section 179 would not apply. Id.

110(a)(2)(D)(ii): Interstate and International Transport Provisions
    For the EPA's analysis of CAA section 110(a)(2)(D)(ii), we reviewed
the sections of the North Dakota SIP referenced by the State in its
2015 Ozone infrastructure SIP submission. As required by 40 CFR
51.166(q)(2)(iv), North Dakota's SIP-approved PSD program requires
notice of proposed new sources or modifications to states whose lands
may be significantly affected by emissions from the source or
modification (see NDAC 33-15-15-01.2.1(q)(2)(d)). This provision
satisfies the notice requirement of section 126(a). North Dakota also
has no pending obligations under sections 126(c) or 115(b). Therefore,
the North Dakota SIP currently meets the requirements of those
sections. On these bases, the EPA is proposing to find that the North
Dakota SIP meets the requirements of CAA section 110(a)(2)(D)(ii) for
the 2015 ozone NAAQS.

E. CAA Section 110(a)(2)(E): Adequate Resources

    Section 110(a)(2)(E)(i) requires states to provide necessary
assurances that the State will have adequate personnel, funding, and
authority under state law to carry out the SIP (and is not prohibited
by any provision of Federal or state law from carrying out the SIP or
portion thereof). Section 110(a)(2)(E)(ii) requires each state to
comply with the requirements respecting state boards under CAA section
128. Section 110(a)(2)(E)(iii) requires states to ``provide necessary
assurances that, where the State has relied on a local or regional
government, agency, or instrumentality for the implementation of any
[SIP] provision, the State has responsibility for ensuring adequate
implementation of such [SIP] provision.''
1. Colorado
    The State's submission and the EPA's analysis:
    Sub-elements (i) and (iii): Adequate personnel, funding, and legal
authority under state law to carry out its SIP, and related issues.
    Colorado Revised Statutes, specifically the Colorado Air Pollution
Prevention and Control Act (APPCA) Sections 25-7-105, 25-7-11, 42-4
301, to 42-4-414 and Article 7 of Title 25, provide adequate authority
for the State of Colorado APCD and AQCC to carry out its SIP
obligations with respect to the 2015 ozone NAQQS. The submission states
the APCD has an annual budget to operate its six programs which employs
176 people, and for fiscal year 2018 the APCD had a budget of $18
million. The budget indicates that 50 percent of funding was derived
from stationary source fees, 30 percent being from mobile source fees,
17 percent from Federal grants, and the remaining three percent coming
from other cash sources.
    The State also receives Sections 103 and 105 grand funds through
its Performance Partnership Grant (PPG) along with required state
matching funds to provide funding necessary to carry out Colorado's SIP
requirements. The regulations cited by Colorado in their certifications
and contained within this docket also provide the necessary assurances
that the State has responsibility for adequate implementation of SIP
provisions by local governments. Therefore, we propose to approve
Colorado's SIP as meeting the requirements of section 110(a)(E)(i) and
(E)(iii) for the 2015 ozone NAAQS.
    Sub-element (ii): State boards.
    Section 110(a)(2)(E)(ii) requires each state's SIP to contain
provisions that comply with the requirements of section 128 of the CAA.
Section 128 requires SIPs to contain two explicit requirements: (i)
That any board or body which approves permits or enforcement orders
under the CAA shall have at least a majority of members who represent
the public interest and do not derive a significant portion of their
income from persons subject to such permits and enforcement orders; and
(ii) that any potential conflicts of interest by members of such board
or body or the head of an executive agency with similar powers be
adequately disclosed.\38\
---------------------------------------------------------------------------

    \38\ EPA's proposed rule document (79 FR 71040, Dec. 1, 2014)
includes a discussion of the legislative history of CAA section 128.
---------------------------------------------------------------------------

    On April 10, 2012 (77 FR 21453) the EPA approved the Procedural
Rules, Section 1.11.0, as adopted by the AQCC on January 16, 1998, into
the Colorado SIP as meeting the requirements of section 128 of the Act.
Section 1.11.0 specifies certain requirements regarding the composition
of the AQCC and disclosure by its members of potential conflicts of
interest. Details on how this portion of the Procedural Rules meet the
requirements of section 128 are provided in our January 4, 2012
proposal document (77 FR 235). In our April 10, 2012 action, we
correspondingly approved Colorado's infrastructure SIP for the 1997
ozone NAAQS for element (E)(ii). Colorado's SIP continues to meet the
requirements of section 110(a)(2)(E)(ii), and we propose to approve
Colorado's infrastructure SIP for the 2015 ozone NAAQS for this
element.
2. North Dakota
    The State's submission and the EPA's analysis:
    Sub-elements (i) and (iii): Adequate personnel, funding, and legal
authority under state law to carry out its SIP, and related issues.
    The North Dakota submission cites NDCC 23.1-06-04.1.1 which
provides the NDEQ adequate personnel, funding, and legal authority to
carry out its SIP and related issues. In addition, the NDEQ currently
has 17 full time staff dedicated to permitting of new or modified
sources of air pollution and the enforcement of the APCR. NDCC 23-25-
03.1 provides adequate authority for the State of North Dakota and the
NDEQ to carry out its SIP obligations with respect to the 2015 ozone
NAAQS. North Dakota's resources meet the requirements of CAA section
110(a)(2)(E).
    We propose to approve North Dakota's SIP as meeting the
requirements of section 110(a)(2)(E)(i) and (E)(iii) for the 2015 ozone
NAAQS.
    Sub-element (ii): State boards.
    Section 110(a)(2)(E)(ii) requires each state's SIP to contain
provisions that comply with the requirements of section 128 of the CAA.
Section 128 requires SIPs to contain two explicit requirements: (i)
That any board or body which approves permits or enforcements orders
under the CAA shall have at least a majority of members who represent
the public interest and do not derive a significant portion of their
income from persons subject to such permits and enforcement orders; and
(ii) that any potential conflicts of interest by members of such board
or body or the head of an executive agency with similar powers be
adequately disclosed. On July 30, 2013 (78 FR 45866) the EPA approved
revised language in North Dakota's SIP, chapter 2, section 15,
Respecting Boards that addresses conflict of interest requirements.
Details on how this portion of chapter 2, section 15 meets the
requirements of CAA section 128 are provided in the May 13, 2013
proposal document (78 FR 27888). North Dakota's SIP continues to meet
the requirements of section 110(a)(2)(E)(ii), and we propose to approve
the infrastructure SIP for the 2015 ozone NAAQS for this element.

F. CAA Section 110(a)(2)(F): Stationary Source Monitoring System

    Section 110(a)(2)(F) requires the SIP to require, as may be
prescribed by the EPA: (i) The installation, maintenance, and
replacement of equipment, and the

implementation of other necessary steps, by owners or operators of
stationary sources to monitor emissions from such sources, (ii)
Periodic reports on the nature and amounts of emissions and emissions-
related data from such sources, and (iii) Correlation of such reports
by the state agency with any emission limitations or standards
established pursuant to the Act, which reports shall be available at
reasonable times for public inspection.
1. Colorado
    The State's submission and the EPA's analysis:
    The Colorado AQCC Regulations listed in the State's certifications
(Regulations 1, 3, 7, and Common Provisions Regulation) and contained
within this docket provide authority to establish a program for
measurements and testing of sources, including requirements for
sampling and testing. Air Pollutant Emission Notice (APEN) requirements
are defined in Regulation 3 and requires stationary sources to report
their emissions on a regular basis through APENs. Regulation 3 also
requires monitoring to be performed in accordance with EPA-accepted
procedures, and recordkeeping of air pollutants. Additionally,
Regulation 3 provides for a permitting program that establishes
emission limitations and standards. Emissions must be reported by
sources to the state for correlation with applicable emissions
limitations and standards. Monitoring may be required for both
construction and operating permits.
    Additionally, Colorado is required to submit emissions data to the
EPA for purposes of the National Emissions Inventory (NEI). The NEI is
the EPA's central repository for air emissions data. The EPA published
the Air Emissions Reporting Rule (AERR) on December 5, 2008, which
modified the requirements for collecting and reporting air emissions
data (73 FR 76539). The AERR shortened the time states had to report
emissions data from 17 to 12 months, giving states one calendar year to
submit emissions data. All states are required to submit a
comprehensive emissions inventory every three years and report
emissions for certain larger sources annually through the EPA's online
Emissions Inventory System (EIS). States report emissions data for six
criteria pollutants and their associated precursors--NOX,
sulfur dioxide (SO2), ammonia, Pb, carbon monoxide (CO), PM,
and volatile organic compounds (VOCs). Colorado made its latest update
to the NEI on March 5, 2019. The EPA compiles the emissions data,
supplementing it where necessary, and releases it to the general public
through the website http://www.epa.gov/ttn/chief/eiinformation.html.
    Based on the analysis above, we propose to approve the Colorado's
SIP as meeting the requirements of CAA section 110(a)(2)(F) for the
2015 ozone NAAQS.
2. North Dakota
    The State's submission and the EPA's analysis:
    The North Dakota statutory provisions listed in the State's
certifications (NDCC 23-25-03) and contained within this docket provide
authority to establish a program for measurement and testing of
sources, including requirements for sampling and testing. North
Dakota's SIP-approved minor source and PSD programs provide for
monitoring, recordkeeping, and reporting requirements for sources
subject to minor and major source permitting. The State cites several
regulations (NDAC 33-15-14-02.9.1, 33-15-14-03.6.1, 33-15-14-06.5.1 and
contained within this docket) requiring monitoring of emissions from
stationary sources, recordkeeping, and reporting of emissions,
monitoring date. Source surveillance is also addressed in Chapter 8 of
the SIP. The chapter provides for the permitting of sources, inspection
of the sources, recordkeeping and reporting by sources, and compliance
determinations. Section 8.2 of the SIP commits the NDEQ of the
correlation of data with the applicable requirements. All reports are
available for public inspection in accordance with NDAC 33-15-01-
16.1.1. Additionally, North Dakota is required to submit emissions data
to the EPA for purposes of the NEI, as detailed above.
    Based on the analysis above, we propose to approve North Dakota SIP
as meeting the requirements of CAA section 110(a)(2)(F) for the 2015
ozone NAAQS.

G. CAA Section 110(a)(2)(G): Emergency Powers

    Section 110(a)(2)(G) of the CAA requires infrastructure SIPs to
``provide for authority comparable to that in [CAA Section 303] and
adequate contingency plans to implement such authority.''
    Under CAA section 303, the Administrator has authority to
immediately restrain an air pollution source that presents an imminent
and substantial endangerment to public health or welfare, or the
environment. If such action may not practicably assure prompt
protection, then the Administrator has authority to issue temporary
administrative orders to protect the public health or welfare, or the
environment, and such orders can be extended if the EPA subsequently
files a civil suit.
1. Colorado
    The State's submission and the EPA's analysis:
    APPCA Sections 25-7-112 and 25-7-113 provide APCD with general
emergency authority comparable to that in section 303 of the Act. APPCA
section 25-7-112(1) provides the Division of Administration in the
CDPHE with the authority to maintain civil actions over the sources of
air pollution discharges that constitute ``a clear, present, and
immediate danger to the environment or to the health of the public.''
Specifically, the APCD can seek a ``temporary restraining order,
temporary injunction, or permanent injunction as provided for in the
Colorado rules of civil procedure'' (C.R.S. section 25-7-112(1)(b)).
This authority extends to discharges that constitute ``an immediate
danger to the welfare of the public because such pollutants make
habitation of residences or the conduct of businesses subjected to the
pollutants extremely unhealthy or disruptive.'' (C.R.S. Section 25-7-
113(1)).
    These civil actions may be maintained ``in any district court of
this state for the district in which the said activity or discharge is
occurring.'' (C.R.S. Sections 25-7-112(1)(b); 25-7-113(1)(b)).
Additionally, the action ``shall be given precedence over all other
matters pending in such district court.'' (Id). As such, Colorado law
provides statutory authority over sources of air pollution discharges
that cause an ``immediate danger'' to public health, welfare, or the
environment. This authority allows for the pursuit of immediate relief
and provides precedence for such matters. Therefore, Colorado has
comparable judicial authority to that provided to the Administrator in
Section 303.
    Similarly, APPCA section 25-7-112(1)(a) provides the APCD with the
authority to issue ``cease-and-desist orders . . . requiring immediate
discontinuance of such activity or the discharge of such pollutant into
the atmosphere'' when the activity or discharge ``constitutes a clear,
present, and immediate danger to the environment or to the health of
the public.'' (C.R.S. Section 25-7-112(1)(a)). Further, ``upon receipt
of such order, such person shall immediately discontinue such activity
or discharge.'' (Id). This authority extends to discharges that
constitute ``an immediate danger to the welfare of the public because
such pollutants make

habitation of residences or the conduct of businesses subjected to the
pollutants extremely unhealthy or disruptive.'' (C.R.S. Section 25-7-
113(1)).
    These provisions also allow the APCD to ``both issue such a cease-
and-desist order and apply for any such restraining order or
injunction'' (C.R.S. Sections 25-7-112(1)(c); 25-7-113(c)). Colorado
law provides administrative authority over sources of air pollution
discharges that cause an ``immediate danger'' to public health,
welfare, or the environment. Furthermore, C.R.S. Sections 25-7-
112(2)(b) allows the Governor to declare a state of air pollution
emergency and take any and all actions necessary to protect the health
of the public. This authority is comparable to that provided to the
Administrator in Section 303.
    The SIP therefore meets the requirements of 110(a)(2)(G). Based on
the above analysis, we propose approval of Colorado's SIP as meeting
the requirements of CAA section 110(a)(2)(G) for the 2015 ozone NAAQS.
2. North Dakota
    The State's submission and the EPA's analysis:
    Chapter 23-25 of the NDCC provides relevant language and authority
for ``Air Pollution Control.'' The purpose of this chapter is ``to
achieve and maintain the best air quality possible'' and to ``protect
human health, welfare and property, [and] prevent injury to plant and
animal life'' (NDCC 23-25-01.1(2)). NDCC 23-25-01.1 defines ``air
pollution'' as ``the presence in the outdoor atmosphere of one or more
air contaminants in such quantities and duration as is or may be
injurious to human health, welfare, or property, animal or plant life,
or which unreasonably interferes with the enjoyment of life or
property.'' As such, the chapter aims to protect all three areas
required by section 303; human health, welfare, and environment. The
``Air Pollution Control'' chapter provides general grants of authority
to maintain actions in certain situations. We find these grants provide
comparable authority to that provided in Section 303. Furthermore, the
NDAC 33-15-01-15.1(1) makes it unlawful to ``permit or cause air
pollution'' as defined in NDCC 23-25-01.1. A person causing or
contributing to emissions that endanger public health, welfare, or the
environment, would be causing ``air pollution'' within the meaning of
North Dakota law, and would therefore be in violation of NDAC 33-15-01-
15.1(1). This could occur in either an emergency or non-emergency
situation.
    NDCC 23-25-10.1(5) provides that ``the department has the authority
to maintain an action in the name of the state against any person to
enjoin any threatened or continuing violation of any provision of this
chapter or any permit condition, rule, order, limitation, or other
applicable requirement implementing this chapter.'' Under NDCC 23-25-
10.1(5), the NDEQ has the authority to bring an action to enjoin a
violation of NDCC 23-25.1 or its rules. The NDEQ may seek a court order
to restrain a source from causing or contributing to emissions that
endanger public health, welfare, or the environment. In an emergency,
this may take the form of an injunction or temporary restraining order
(see NDCC 32-06-02.1). Therefore, the NDEQ has the authority to seek
judicial actions during emergency situations.
    North Dakota's statutes also provide the NDEQ with the authority to
issue administrative orders and emergency rules to protect the public
health, welfare, and the environment under certain circumstances. NDCC
23-25-08.1, as cited in North Dakota's SIP submittals, authorizes that
in the event of ``an emergency requiring immediate action to protect
the public health and safety,'' the NDEQ has the authority to ``issue
an order reciting the existence of such emergency and requiring that
such action be taken as is necessary'' to meet the emergency. The
emergency order is effective immediately. Any person who violates the
order is subject to enforcement, penalties, and injunctions under NDCC
23-25-10.1.
    Furthermore, as cited in North Dakota's SIP submittals, the NDEQ
has the authority to ``use an emergency adjudicative proceeding, in its
discretion, in an emergency situation involving imminent peril to the
public health, safety, or welfare'' (NDCC 28-32-32.1). Accordingly,
``in an emergency, the administrative agency may take action pursuant
to a specific statute as is necessary to prevent or avoid imminent
peril to the public health, safety, or welfare'' (NDCC-28-32-32.1.1).
In the absence of a specific statute requiring other administrative
action, ``the administrative agency shall issue an order'' (NDCC 28-32-
32.1(4)).
    Further supplemental authority is found in a broad provision, cited
by the State in their SIP submittals, granting additional authority to
the NDEQ. The NDEQ has the authority to ``[i]ssue such orders as may be
necessary to effectuate the purposes'' of the ``Air Pollution Control''
chapter NDCC 23-25-03.5.1. These orders can be enforced ``by all
appropriate administrative and judicial procedures'' (NDCC 23-25-
03.5.1). Thus, this broad grant of authority includes the authority to
issue administrative orders during air pollution emergencies which
would disrupt protection of human health, welfare, and animal and plant
life.
    The combination of NDCC and NDAC provisions discussed above provide
for authority comparable to section 303 to immediately bring suit to
restrain, issue emergency orders against, and use special rule adoption
procedures for applicable emergencies to take prompt administrative
action against, any person causing or contributing to air pollution
that presents an imminent and substantial endangerment to public health
or welfare, or the environment. We propose that they are sufficient to
meet the authority requirement of CAA section 110(a)(2)(G).
    States must also have adequate contingency plans adopted into their
SIP to implement the air agency's emergency episode authority (as
discussed above). Requirements for contingency plans are set forth in
40 CFR part 51, subpart H.
    Subpart H of 40 CFR part 51 requires states to classify regions and
to develop contingency plans (also known as emergency episode plans)
after ambient concentrations of certain criteria pollutants in an area
have exceeded specified levels. For example, if ambient concentrations
of NO2 in an area have exceeded 0.06 parts per million (ppm)
(annual arithmetic mean), then the area is classified as a Priority I
region, and the state must develop a contingency plan that meets the
requirements of Sec. Sec.  51.151.1 and 51.152.1 North Dakota has not
monitored any values above the priority cut point for ozone or
NO2.
    Prevention of air pollution emergency episodes is addressed in
Section 5 of North Dakota's SIP, which was approved on May 31, 1972 (37
FR 10842). We find that North Dakota's air pollution emergency
provisions establish stages of episode criteria (Section 5.2), provide
for public announcement whenever any episode stage has been determined
to exist (Section 5.3), and specify emission control actions to be
taken at each episode stage (Section 5.5) consistent with the EPA
emergency episode SIP requirements set forth at the 40 CFR part 51,
subpart H (prevention of air pollution emergency episode) for ozone and
NO2.
    Based on the above analysis, we propose approval of North Dakota's
SIP as meeting the requirements of CAA section 110(a)(2)(G) for the
2015 ozone NAAQS.

H. CAA Section 110(a)(2)(H): Future SIP Revisions

    Section 110(a)(2)(H) requires that SIPs provide for revision of
such plan: (i) From time to time as may be necessary to take account of
revisions of such national primary or secondary ambient air quality
standard or the availability of improved or more expeditious methods of
attaining such standard, and (ii), except as provided in paragraph
(3)(C), whenever the Administrator finds on the basis of information
available to the Administrator that the SIP is substantially inadequate
to attain the NAAQS which it implements or to otherwise comply with any
additional requirements under this [Act].
1. Colorado
    The State's submission and the EPA's analysis:
    The Colorado submission refers to the Colorado APPCA Section 25-7-
105(1)(a)(I) which directs the AQCC to promulgate a comprehensive SIP
that meets all Federal requirements and to revise the SIP whenever
necessary or appropriate. In addition, the Colorado APPCA Section 25-7-
109 C.R.S. gives the AQCC the authority to promulgate emissions control
regulations.
    Colorado's statutory provision at APPCA Section 25-7-105(1)(a)(I)
directs the AQCC to promulgate a comprehensive SIP that meets all
Federal requirements and to revise the SIP whenever necessary or
appropriate. Therefore, we propose to approve Colorado's SIP as meeting
the requirements of CAA section 110(a)(2)(H).
2. North Dakota
    The State's submission and the EPA's analysis:
    The EPA approved section 1.14 of the North Dakota SIP on September
17, 2012 (77 FR 57029). Section 1.14 commits the State to revise the
SIP in the circumstances covered by CAA section 110(a)(2)(H). North
Dakota's statutory provision at NDCC 23-25-03.1 provides adequate
authority for the NDEQ to carry out such revisions. Therefore, we
propose to approve North Dakota's SIP as meeting the requirements of
CAA section 110(a)(2)(H).

I. CAA Section 110(a)(2)(I): Nonattainment Area Plan Revision Under
Part D

    There are two elements identified in CAA section 110(a)(2) are not
governed by the three-year submission deadline of CAA section 110(a)(1)
because SIPs incorporating necessary local nonattainment area controls
are due on nonattainment area plan schedules pursuant to section 172
and the various pollutant-specific subparts 2 through 5 of part D.
These are submissions required by: (i) CAA section 110(a)(2)(C) to the
extent that subsection refers to a permit program as required in part
D, Title I of the CAA, and (ii) section 110(a)(2)(I) which pertain to
the nonattainment planning requirements of part D, Title I of the CAA.
As a result, this action does not address CAA section 110(a)(2)(C) with
respect to NNSR or CAA section 110(a)(2)(I).

J. CAA Section 110(a)(2)(J): Consultation With Government Officials,
Public Notification, PSD and Visibility Protection

    CAA section 110(a)(2)(J) requires states to provide a process for
consultation with local governments and FLMs pursuant to CAA section
121. CAA section 110(a)(2)(J) further requires states to notify the
public if NAAQS are exceeded in an area and to enhance public awareness
of measures that can be taken to prevent exceedances pursuant to CAA
section 127. Lastly, CAA section 110(a)(2)(J) requires states to meet
applicable requirements of part C, Title I of the CAA related to
prevention of significant deterioration and visibility protection.
1. Colorado
    (i) State's submission:
    The Colorado submission references the following laws and
regulations relating to consultation with identified officials on
certain air agency actions; public notification; PSD; and visibility
protection:
     APPCA 25-7-105(1)(d).
     APPCA 25-7-118.
     APPCA 25-7-128.
     AQCC Regulation 3 (Stationary Source Permitting and Air
Pollution Emission Notice Requirements).
     AQCC Regulation 6 (Standards of Performance for New
Stationary Sources).
     AQCC Regulation 10, Part III (Transportation Conformity
Rule).
     Colorado's Regional Haze SIP.
     Colorado's Interstate Transport SIP.
    (ii) The EPA's analysis:
    Colorado has demonstrated that it has the authority and rules in
place to provide a process of consultation with general purpose local
governments, designated organizations of elected officials of local
governments and any FLM having authority over Federal land to which the
SIP applies, consistent with the requirements of CAA section 121.
Moreover, the EPA previously addressed the requirements of CAA section
127 for the Colorado SIP and determined public notification
requirements are appropriate (45 FR 53147, Aug. 11, 1980).
    Addressing the requirement in CAA section 110(a)(2)(J) that the SIP
meet the applicable requirements of part C, Title I of the CAA, we have
evaluated this requirement in the context of CAA section 110(a)(2)(C).
The EPA most recently approved revisions to Colorado's PSD program on
May 3, 2019 (84 FR 18991), updating the program for current Federal
requirements. Therefore, we are proposing to approve the Colorado SIP
as meeting the requirements of CAA 110(a)(2)(J) with respect to PSD for
the 2015 ozone NAAQS.
    With regard to applicable visibility protection requirements, the
EPA recognizes that states are subject to visibility and regional haze
program requirements under part C of the Act. In the event of the
establishment of a new NAAQS, however, the visibility and regional haze
program requirements under part C do not change. Consequently, we find
that there is no new applicable requirement relating to visibility
triggered under CAA section 110(a)(2)(J) when a new NAAQS becomes
effective.
    Based on the above analysis, we are proposing to approve the
Colorado SIP as meeting the requirements of CAA section 110(a)(2)(J)
for the 2015 ozone NAAQS.
2. North Dakota
    (i) State's submission:
    The North Dakota submission references the following specific laws
and regulations relating to consultation with identified officials on
certain air agency actions, public notification, prevention of
significant deterioration, and visibility protection:

 North Dakota SIP, Chapter 10
 North Dakota SIP, Section 6.9
 NDCC 23.1-06-12
 NDCC 23.1-06-13
 NDCC 28-32
 NDAC 33.1-15-11-03.1
 NDAC 33.1-15-14-02.6
 NDAC 33.1-15-15-01.2(k)(i)
 NDAC 33.1-15-15-01.2(p)
 NDAC 33.1-15-15-01.2(q)

    (ii) EPA's analysis:
    North Dakota has demonstrated that it has the authority and rules
in place to provide for a process of consultation with local
governments, designated organizations of elected officials of local
governments and any FLM having authority over Federal land to which the
SIP applies, consistent with the requirements of CAA section 121.
Moreover, the EPA previously

addressed the requirements of CAA section 127 for the North Dakota SIP
and determined public notification requirements are appropriate (45 FR
53475, Aug. 12, 1980).
    Addressing the requirement in CAA section 110(a)(2)(J) that the SIP
meet the applicable requirements of part C, Title I of the CAA, we have
evaluated this requirement in the context of CAA section 110(a)(2)(C).
The EPA most recently approved revisions to North Dakota's PSD program
on June 3, 2010 (75 FR 31291), updating the program for current Federal
PSD requirements. Additionally, the North Dakota's SIP-approved PSD
program incorporates by reference the Federal program at 40 CFR 52.21.
Accordingly, we are proposing to approve the North Dakota SIP as
meeting the requirements of CAA 110(a)(2)(J) with respect to PSD for
the 2015 ozone NAAQS.
    With regard to applicable visibility protection requirements, the
EPA recognizes that states are subject to visibility and regional haze
program requirements under part C of the Act. In the event of the
establishment of a new NAAQS, however, the visibility and regional haze
program requirements under part C do not change. Consequently, we find
that there is no new applicable requirement relating to visibility
triggered under CAA section 110(a)(2)(J) when a new NAAQS becomes
effective.
    Based on the above analysis, we are proposing to approve the North
Dakota SIP as meeting the requirements of CAA section 110(a)(2)(J) for
the 2015 ozone NAAQS.

K. CAA Section 110(a)(2)(K): Air Quality and Modeling/Data

    CAA section 110(a)(2)(K) requires that SIPs provide for (i) the
performance of air quality modeling as the Administrator may prescribe
for the purpose of predicting the effect on ambient air quality of any
emissions of any air pollutant for which the Administrator has
established a NAAQS, and (ii) the submission, upon request, of data
related to such air quality modeling to the Administrator.
    The EPA's requirements for air quality modeling for criteria
pollutants are found in 40 CFR part 51, appendix W, Guideline on Air
Quality Models. On January 17, 2017 (82 FR 5182), the EPA revised
appendix W, effective February 16, 2017. The Federal Register notice
stated: ``For all regulatory applications covered under the Guideline,
except for transportation conformity, the changes to the appendix A
preferred models and revisions to the requirements and recommendations
of the Guideline must be integrated into the regulatory processes of
respective reviewing authorities and followed by applicants by no later
than January 17, 2018.''
1. Colorado
    (i) State's submission:
    The Colorado submission refers to Colorado's Regulation 3 Part
A.VIII (Technical Modeling and Monitoring Requirements) which requires
that estimates of ambient air concentrations are based on applicable
air quality models approved by the EPA. Further, Regulation 3 Part D,
Section VI.C. requires the APCD to transmit to the Administrator of the
EPA a copy of each permit application relating to a major stationary
source or major modification subject to this regulation and provide
notice of every action related to the consideration of such permit. The
State also references the following rules and regulations which require
and provide authority for air quality modeling and submission of such
data to the EPA Administrator:
     Regulation 3.
     Regulation 3 Part A, Section VIII.
     Regulation 3, Part D, Section X.A.4.
     Regulation 3, Part D, Section VI.C.
     AQCC Regulation 4.
     Denver PM10 SIP.
    (ii) The EPA's analysis:
    Colorado has broad authority and resources to model for all
criteria pollutants. Air quality modeling is done for SIP revisions,
transportation conformity, and permitting. AQCC Regulation 3
(Stationary Source Permitting and Air Pollution Emission Notice
Requirements) requires stationary sources to predict the effect of air
pollutants in attainment areas. Regulation 3 also details the State of
Colorado's program regarding permitting as related to air quality
modeling and data handling in predicting the effect of emissions of a
pollutant with an established NAAQS.
    Colorado Regulation 3 Part A, Section VIII, ``Technical Modeling
and Monitoring Requirements,'' most recently approved by the EPA on
January 25, 2016 (81 FR 3963), states that all estimates of ambient
concentrations required under Regulation 3 shall be based on the
applicable air quality models, data bases, and other requirements
generally approved by the EPA and specifically approved by the APCD.
Part A also requires all modeling data used to determine compliance to
be appropriate given the topography, meteorology and other
characteristics of the region. In previous actions, the EPA has
interpreted Colorado's provisions on permit modeling to mean that the
modeling is performed in accordance with appendix W of 40 CFR part 51.
Because the provision requires use of EPA-approved models without
setting any cutoff date for that approval, we interpret the provision
to mean EPA-approved models as they are currently approved. As
confirmation, Colorado's May 2018 draft modeling guidance (contained in
the docket), ``Colorado Modeling Guideline for Air Quality Permits''
has been revised and updated to refer to the most recent version of
appendix W described above.\39\
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    \39\ For our most recent Colorado infrastructure SIP approval,
see 82 FR 39030, September 18, 2017. See also https://www3.epa.gov/airquality/urbanair/sipstatus/reports/co_infrabypoll.html.
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    The state submits data to the EPA as required under Regulation 3,
Part D, Section VI.C., most recently approved by the EPA on January 25,
2016 (81 FR 3963), requiring Colorado to transmit to the EPA
Administrator a copy of each permit application relating to a major
stationary source or major modification subject to the regulation, and
provide notice of every action related to the consideration of such
permit. Additionally, the State also has the authority to submit any
modeling data to the EPA upon request under the Colorado Open Records
Act.\40\
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    \40\ See 24-72-201 to 24-72-309, C.R.S.
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    Based on the above information, we are proposing to approve the
Colorado SIP as meeting the requirements of CAA section 110(a)(2)(K)
for the 2015 ozone NAAQS.
2. North Dakota
    (i) State's submission:
    The North Dakota submission refers to the following rules and
regulations that provide for NAAQS pollutant air quality modeling and
the submission of such data to EPA:

 North Dakota SIP, section 7.7, Air Quality Modeling
 NDAC 33.1-15-14-02.4
 NDCC 23.1-06-04.1

    (ii) EPA's analysis:
    North Dakota's PSD program requires that estimates of ambient air
concentrations are based on applicable air quality models specified in
appendix W of 40 CFR part 51, and incorporates by reference \41\ the
provisions at 40 CFR 52.21(i)(2) requiring that modification or
substitution of a model specified in appendix W must be approved by the
Administrator (see NDAC 33.1-15-14-

02.4 and NDAC 33.1-15-15-01.2). Section 7.7, Air Quality Modeling, last
approved by the EPA on September 17, 2009 (77 FR 10842) of North