Document ID: EPA-R08-OAR-2020-0114-0001
Agency: epa
Document Type: Proposed Rule
Title: Air Quality State Implementation Plans; Approvals and Promulgations: Colorado; Revisions to Regulation Number 7 and Reasonably Available Control Technology Requirements for 2008 8-Hour Ozone Standard for the Denver Metro/North Front Range Nonattainment Area
Posted Date: 2020-10-06T04:00Z

[Federal Register Volume 85, Number 194 (Tuesday, October 6, 2020)]
[Proposed Rules]
[Pages 63066-63077]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-20099]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R08-OAR-2020-0114; FRL-10014-26-Region 8]

Approval and Promulgation of Implementation Plans; Colorado; 
Revisions to Regulation Number 7 and RACT Requirements for 2008 8-Hour 
Ozone Standard for the Denver Metro/North Front Range Nonattainment 
Area

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: The Environmental Protection Agency (EPA) is proposing 
approval and conditional approval of State Implementation Plan (SIP) 
revisions submitted by the State of Colorado on May 31, 2017, May 14, 
2018, and May 10, 2019. The revisions are to Colorado Air Quality 
Control Commission (Commission or AQCC) Regulation Number 7 (Reg. 7). 
The revisions to Reg. 7 address Colorado's reasonably

[[Page 63067]]

available control technology (RACT) SIP obligations for Moderate 2008 
ozone nonattainment areas; add incorporation by reference dates to 
rules and reference methods; and make typographical, grammatical, and 
formatting corrections. Also, in this action, the EPA is proposing to 
correct a July 3, 2018 final rule pertaining to Colorado's SIP. In that 
action, we inadvertently excluded regulatory text corresponding to 
``incorporation by reference'' (IBR) materials for graphic arts and 
printing revisions to Reg. 7, Section XIII (adopted November 17, 2016). 
The EPA is taking this action pursuant to the Clean Air Act (CAA).

DATES: Written comments must be received on or before November 5, 2020.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-R08-
OAR-2020-0114, 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 electronically in 
www.regulations.gov. To reduce the risk of COVID-19 transmission, for 
this action we do not plan to offer hard copy review of the docket. 
Please email or call the person listed in the FOR FURTHER INFORMATION 
CONTACT section if you need to make alternative arrangements for access 
to the docket.

FOR FURTHER INFORMATION CONTACT: Abby Fulton, Air and Radiation 
Division, EPA, Region 8, Mailcode 8ARD-IO, 1595 Wynkoop Street, Denver, 
Colorado 80202-1129, Telephone number: (303) 312-6563, email address: 
fulton.abby@epa.gov.

SUPPLEMENTARY INFORMATION: Throughout this document wherever ``we,'' 
``us,'' or ``our'' is used, we mean the EPA.

I. What action is the Agency taking?

    As explained below, the EPA is proposing to approve various 
revisions to the Colorado SIP that were submitted to the EPA on May 31, 
2017, May 14, 2018, and May 10, 2019. In particular, we propose to 
approve certain area source rules to meet the 2008 8-hour ozone 
national ambient air quality standards (NAAQS) RACT requirements for 
Moderate nonattainment areas that were not acted on in our July 3, 2018 
rulemaking approving the State's attainment demonstration and various 
SIP elements.\1\ We are also proposing to approve into the SIP the 
submitted revisions to Colorado's Reg. 7 that we have not previously 
acted on, except for Sections XII and XVIII (from the May 2018 
submittal) and Sections XVI.D.4.b.(i) and XVI.D.4.d. (from the two May 
2019 submittals), which we will be acting on at a later date (see 
Tables 4, 5 and 6). Finally, we propose to approve IBR material 
submitted in May 2017 but inadvertently excluded from our July 3, 2018 
action.
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    \1\ See Final Rule, Approval and Promulgation of State 
Implementation Plan Revisions; Colorado; Attainment Demonstration 
for the 2008 8-Hour Ozone Standard for the Denver Metro/North Front 
Range Nonattainment Area, and Approval of Related Revisions, 83 FR 
31068, 31069-31072.
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    The specific bases for our proposed actions and our analyses and 
proposed findings are discussed in this proposed rulemaking. Technical 
information that we are relying on is in the docket, available at 
http://www.regulations.gov, Docket No. EPA-R08-OAR-2020-0114.

II. Background

2008 8-Hour Ozone NAAQS Nonattainment

    On March 12, 2008, the EPA revised both the primary and secondary 
NAAQS for ozone to a level of 0.075 parts per million (ppm) (based on 
the annual fourth-highest daily maximum 8-hour average concentration, 
averaged over 3 years), to provide increased protection of public 
health and the environment.\2\ The 2008 ozone NAAQS retains the same 
general form and averaging time as the 0.08 ppm NAAQS set in 1997, but 
is set at a more protective level. Specifically, the 2008 8-hour ozone 
NAAQS is attained when the 3-year average of the annual fourth-highest 
daily maximum 8-hour average ambient air quality ozone concentrations 
is less than or equal to 0.075 ppm.\3\
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    \2\ Final rule, National Ambient Air Quality Standards for 
Ozone, 73 FR 16436 (March 27, 2008).
    \3\ 40 CFR 50.15(b).
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    Effective July 20, 2012, the EPA designated as nonattainment any 
area that was violating the 2008 8-hour ozone NAAQS based on the three 
most recent years (2008-2010) of air monitoring data.\4\ With that 
rulemaking, the Denver-Boulder-Greeley-Ft. Collins-Loveland, Colorado 
area (Denver or DMNFR Area) area was designated nonattainment and 
classified as Marginal.\5\ Ozone nonattainment areas are classified 
based on the severity of their ozone levels, as determined using the 
area's design value. The design value is the 3-year average of the 
annual fourth highest daily maximum 8-hour average ozone concentration 
at a monitoring site.\6\ Areas that were designated as Marginal 
nonattainment were required to attain the 2008 8-hour ozone NAAQS no 
later than July 20, 2015, based on 2012-2014 monitoring data.\7\
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    \4\ Final rule, Air Quality Designations for the 2008 Ozone 
National Ambient Air Quality Standards, 77 FR 30088 (May 21, 2012).
    \5\ Id. at 30110. The nonattainment area includes Adams, 
Arapahoe, Boulder, Broomfield, Denver, Douglas and Jefferson 
Counties, and portions of Larimer and Weld Counties. See 40 CFR 
81.306.
    \6\ 40 CFR part 50, appendix I.
    \7\ See 40 CFR 51.903.
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    On May 4, 2016, the EPA published its determination that the Denver 
Area, among other areas, had failed to attain the 2008 8-hour ozone 
NAAQS by the attainment deadline, and that it was accordingly 
reclassified to Moderate ozone nonattainment status.\8\ Colorado 
submitted SIP revisions to the EPA on May 31, 2017 to meet the Denver 
Area's requirements under the Moderate classification.\9\ The EPA took 
final action on July 3, 2018, approving the majority of the May 31, 
2017 submittal,

[[Page 63068]]

but deferring action on portions of the submitted Reg. 7 RACT 
rules.\10\
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    \8\ Final rule, Determinations of Attainment by the Attainment 
Date, Extensions of the Attainment Date, and Reclassification of 
Several Areas for the 2008 Ozone National Ambient Air Quality 
Standards, 81 FR 26697 (May 4, 2016); see 40 CFR 81.306.
    \9\ CAA section 182, 42 U.S.C. 7511a, outlines SIP requirements 
applicable to ozone nonattainment areas in each classification 
category. Areas classified Moderate under the 2008 8-hour ozone 
NAAQS had a submission deadline of January 1, 2017 for these SIP 
revisions. 81 FR at 26699.
    \10\ 83 FR at 31068. Under the Moderate classification, the 
Denver Area was required to attain the standard by July 20, 2018. It 
did not do so, and as a result has been reclassified to Serious 
nonattainment status. See Final rule, Finding of Failure To Attain 
and Reclassification of Denver Area for the 2008 Ozone National 
Ambient Air Quality Standard, 84 FR 70897 (Dec. 26, 2019).
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SIP Control Measures, Reg. 7

    Colorado's Reg. 7, entitled ``Control of Ozone via Ozone Precursors 
and Control of Hydrocarbons via Oil and Gas Emissions,'' contains 
general RACT requirements as well as specific emission limits 
applicable to various industries. The EPA approved the repeal and re-
promulgation of Reg. 7 in 1981,\11\ and has approved various revisions 
to parts of Reg. 7 over the years. In 2008, the EPA approved revisions 
to the control requirements for condensate storage tanks in Section 
XII,\12\ and the EPA later approved revisions to Reg. 7, Sections I 
through XI and Sections XIII through XVI.\13\ The EPA also approved 
Reg. 7 revisions to control emissions from rich-burn reciprocating 
internal combustion engines in Section XVII.E.3.a.\14\
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    \11\ Final rule, Colorado: Approval and Promulgation of State 
Implementation Plans, 46 FR 16687 (March 13, 1981).
    \12\ Final rule, Approval and Promulgation of Air Quality 
Implementation Plans; State of Colorado; Regulation No. 7, Section 
XII, Volatile Organic Compounds From Oil and Gas Operations, 73 FR 
8194 (Feb. 13, 2008).
    \13\ Final rule, Approval and Promulgation of State 
Implementation Plans; State of Colorado; Attainment Demonstration 
for the 1997 8-Hour Ozone Standard, and Approval of Related 
Revisions, 76 FR 47443 (Aug. 5, 2011).
    \14\ Final rule, Approval and Promulgation of Implementation 
Plans; State of Colorado; Regional Haze State Implementation Plan, 
77 FR 76871 (Dec. 31, 2012).
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    Most recently, in 2018 the EPA approved Reg. 7 revisions in 
Sections XII (emission control requirements for volatile organic 
compounds (VOCs) from oil and gas operations), and XIII (emission 
control requirements for VOC emissions from graphic art and printing 
processes),\15\ as well as non-substantive revisions to numerous other 
parts of the regulation.\16\
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    \15\ In this document we are correcting the previous inadvertent 
omission of IBR material from the regulatory text for this action.
    \16\ See 83 FR at 31068, 31071.
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III. Summary of the State's SIP Submittals

    We are proposing to take action on Colorado SIP submittals made on 
three different dates:

May 31, 2017 Submittal

    This submittal contains revisions to Reg. 7 that the EPA has not 
yet acted on. These include Sections X (Use of Cleaning Solvents), XVI 
(Controls of Emissions from Stationary and Portable Engines and Other 
Combustion Equipment in the 8-Hour Ozone Control Area), and XIX 
(Control of Emissions from Specific Major Sources of VOC and/or 
nitrogen oxides (NOX) in the 8-hour Ozone Control Area). In 
addition, this submittal contains graphic arts and printing revisions 
to Section XIII. In our final rule published in the Federal Register on 
July 3, 2018, we inadvertently did not include regulatory text and 
corresponding IBR materials for our approval to graphic arts and 
printing revisions to Reg. 7, Section XIII (adopted November 17, 
2016).\17\ The EPA is proposing to correct this error with today's 
action. The IBR material for our July 3, 2018 action is in the docket 
for this action.
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    \17\ See 83 FR at 31068.
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May 14, 2018 Submittal

    This submittal contains amendments to Reg. 7 Sections XII and XVIII 
to meet RACT for oil and gas sources covered by EPA's 2016 Oil and Gas 
Control Techniques Guideline (CTG). The submittal also includes 
clarifying revisions and typographical, grammatical, and formatting 
corrections throughout Reg. 7.

May 10, 2019 Submittals

    On this date the State submitted two SIP revisions. One submittal 
contains amendments to Reg. 7 that establish categorical RACT 
requirements for major sources of NOX in the DMNFR Area. 
Specifically, on July 19, 2018 the AQCC adopted RACT requirements in 
Section XVI.D. for boilers, stationary combustion turbines, lightweight 
aggregate kilns, glass melting furnaces, and compression ignition 
reciprocating internal combustion engines (``RICE'') (collectively 
referred to as ``stationary combustion equipment'') located at major 
sources of NOX.\18\
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    \18\ On June 29, 2018, the EPA provided comments on Colorado's 
revised draft ozone SIPs for the DMNFR Area, including the TSD and 
rules in Reg. 7, Section XVI.D.4. These written comments from the 
EPA included some comments applicable to the rules we are proposing 
to act on today. The comment letters can be found within the docket 
for this action at www.regulations.gov.
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    The other submittal contains amendments to Reg. 7 that were adopted 
by the AQCC on November 15, 2018. The revisions include RACT 
requirements in Section XX for brewing-related activities at major 
sources of VOC, and RACT requirements in Section IX for wood furniture 
surface coating operations. The submittal also includes revisions to 
IBR dates to rules and reference methods in Sections II, VI, VIII, IX, 
X, XII, XIII, XVI and XVII. Lastly, the submittal contains SIP cleanup 
revisions, including removal of a one-time RACT reporting requirement 
in Section I, adds a surface coating work practice in Section IX, and 
revises an exemption in the industrial cleaning solvent requirements in 
Section X. Typographical, grammatical, and formatting corrections were 
also made.

IV. Procedural Requirements

    The CAA requires that states meet certain procedural requirements 
before submitting SIP revisions to the EPA, including the requirement 
that states adopt SIP revisions after reasonable notice and public 
hearing.\19\ For the May 31, 2017 submittal, the AQCC provided notice 
in the Colorado Register on July 29 and August 29, 2016, and held a 
public hearing on the SIP revisions on November 17, 2016. The 
Commission adopted the SIP revisions on November 17, 2016. The SIP 
revisions became state-effective on January 14, 2017.
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    \19\ CAA section 110(a)(2), 42 U.S.C. 7410(a)(2),
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    For the May 14, 2018 submittal, the AQCC provided notice in the 
Colorado Register on July 22, 2017 and held a public hearing on the 
revisions on October 19 and 20, 2017. The Commission adopted the SIP 
revisions on November 16, 2017. The SIP revisions became state-
effective on December 20, 2017.
    For the May 10, 2019 submittal (RACT for combustion sources), the 
AQCC provided notice in the Colorado Register on April 21, 2018 and 
held a public hearing on the revisions on July 19, 2018. The Commission 
adopted the SIP revisions on July 19, 2018. The SIP revisions became 
state-effective on September 14, 2018.
    For the May 10, 2019 submittal (RACT for brewing related activities 
and wood furniture surface coating operations), the AQCC provided 
notice in the Colorado Register on August 18, 2018 and held a public 
hearing on the revisions on November 15, 2018. The Commission adopted 
the SIP revisions on November 15, 2018. The revisions became state-
effective on January 14, 2019.
    Accordingly, we propose to find that Colorado met the CAA's 
procedural requirements for reasonable notice and public hearing.

V. Reasonably Available Control Technology (RACT) Analysis

A. Background

    The CAA requires that SIPs for nonattainment areas ``provide for 
the

[[Page 63069]]

implementation of all reasonably available control measures as 
expeditiously as practicable (including such reductions in emissions 
from existing sources in the area as may be obtained through the 
adoption, at a minimum, of reasonably available control technology).'' 
\20\ The EPA has defined RACT as the lowest emissions limitation that a 
particular source is capable of meeting by the application of control 
technology that is reasonably available, considering technological and 
economic feasibility.\21\ The CAA amendments of 1990 introduced the 
requirement for existing major stationary sources of NOX in 
nonattainment areas to install and operate NOX RACT. 
Specifically, section 182(b)(2) of the CAA requires states to adopt 
RACT for all major sources of VOC not covered by an existing CTG in 
ozone nonattainment areas, and section 182(f) requires the RACT 
provisions for major stationary sources of NOX.
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    \20\ CAA section 172(c)(1), 42 U.S.C. 7502(c)(1).
    \21\ Proposed rule, General Preamble for Proposed Rulemaking on 
Approval of Plan Revisions for Nonattainment Areas--Supplement (on 
Control Techniques Guidelines), 44 FR 53761, 53762 (Sep. 17, 1979).
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    The EPA provides guidance concerning what types of controls can 
constitute RACT for a given source category by issuing CTG and 
Alternative Control Techniques (ACT) documents.\22\ States must submit 
a SIP revision requiring the implementation of RACT for each source 
category in the area for which the EPA has issued a CTG, and for any 
major source in the area not covered by a CTG.\23\
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    \22\ See https://www.epa.gov/ground-level-ozone-pollution/control-techniques-guidelines-and-alternative-control-techniques 
(accessed April. 27, 2020) for a list of EPA-issued CTGs and ACTs 
(also available within the docket).
    \23\ See CAA section 182(b)(2), 42 U.S.C. 7511a(b)(2)). See also 
Note, RACT Qs & As--Reasonably Available Control Technology (RACT): 
Questions and Answers, William Harnett, Director, Air Quality Policy 
Division, EPA (May 2006), available at https://www3.epa.gov/ttn/naaqs/aqmguide/collection/cp2/20060518_harnett_ract_q&a.pdf.
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    For a Moderate nonattainment area, a major stationary source is one 
that emits, or has the potential to emit, 100 tons per year (tpy) or 
more of VOCs or NOX.\24\ RACT can be adopted in the form of 
emission limitations or ``work practice standards or other operation 
and maintenance requirements,'' as appropriate.\25\ In assessing RACT 
requirements under the Moderate classification, the Colorado Air 
Pollution Control Division (Division) identified 51 major sources in 
the DMNFR Area, operated by 32 companies.
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    \24\ See CAA sections 182(b), 42 U.S.C. 7511a(b); and 302(j), 42 
U.S.C. 7602(j).
    \25\ See Memorandum, ``Approval Options for Generic RACT Rules 
Submitted to Meet the non-CTG VOC RACT Requirement and Certain 
NOX RACT Requirements,'' Sally Shaver, Director, Air 
Quality Strategies & Standards Division, EPA (Nov. 7, 1996), 
available at https://www.epa.gov/sites/production/files/2016-08/documents/shavermemogenericract_7nov1996.pdf.
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    In November 2016, the Commission determined that some major sources 
and CTG VOC source categories were adequately addressed under existing 
SIP requirements. The Commission also adopted new requirements for some 
major sources and CTG VOC source categories. In July 2018, the 
Commission adopted categorical RACT requirements for combustion 
equipment at major sources that the Commission had determined in 2016 
were not addressed by SIP RACT requirements. In November 2018, the 
Commission adopted SIP requirements to include provisions that 
implement RACT for major sources of VOC and NOX and for all 
CTG VOC source categories in the DMNFR ozone nonattainment area (NAA). 
Specifically, the Commission adopted categorical RACT requirements for 
combustion equipment at major sources, major source breweries and wood 
furniture manufacturing, and addressed EPA concerns with industrial 
cleaning solvent and metal furniture surface coating requirements.\26\
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    \26\ The Commission also adopted miscellaneous metal surface 
coating requirements. We will be making our RACT determination for 
these sources in a future rulemaking.
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B. Evaluation

    As part of its May 31, 2017 and May 10, 2019 submittals, the 
Division conducted RACT analyses to demonstrate that the RACT 
requirements for CTG and major sources in the DMNFR 2008 8-hour ozone 
NAA have been fulfilled. The Division conducted these RACT analyses for 
VOC and NOX by listing the state regulation that implements 
or exceeds RACT requirements for each CTG or non-CTG category at issue, 
and by detailing the basis for concluding that these regulations 
fulfill RACT, through comparison with established RACT requirements 
described in the CTG and ACT guidance documents and rules developed by 
other state and local agencies. A summary of our proposed action with 
respect to each RACT category follows.

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                Category                        Proposed action              Location of RACT demonstration
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Aerospace...............................  Conditional approval of the  n/a.
                                           State's negative
                                           declaration that there are
                                           no sources in the DMNFR
                                           Area subject to the
                                           aerospace CTG.
Certain Major sources of NOX and VOC....  Approval...................  pp. 1119-1120 and 1142-1149 of the May
                                                                        31, 2017 submittal and the Technical
                                                                        Support Document for Reasonably
                                                                        Available Control Technology for Major
                                                                        Sources, November 17, 2016 (p. 2990-3273
                                                                        of May 10, 2017 submittal).
Combustion equipment at major sources...  Approval...................  Categorical Reasonably Available Control
                                                                        Technology Review for Boilers, Turbines,
                                                                        Engines, Glass Melt Furnaces and
                                                                        Aggregate Kilns and Major NOX Sources in
                                                                        the Denver Metro/North Front Range Ozone
                                                                        Nonattainment Area, July 2018, document
                                                                        set 25 (contained within the May 31,
                                                                        2019 submittal for combustion
                                                                        equipment).
Industrial cleaning solvents............  Approval...................  p. 1116 of the May 31, 2017 submittal and
                                                                        p. 4 of the Statement of Basis, document
                                                                        set 18 (contained within the May 10,
                                                                        2019 submittal for RACT for brewing
                                                                        related activities and wood furniture
                                                                        surface coating operations).
Major Source Breweries..................  Approval...................  State of Colorado Categorical Reasonable
                                                                        Available Control Technology Review for
                                                                        Brewing and Wood Furniture Surface
                                                                        Coating TSD, October 30, 2018, p. 5,
                                                                        document set 21 (contained within the
                                                                        May 10, 2019 submittal).
Metal furniture coatings................  Approval...................  p. 1126 of the May 31, 2017 submittal.

[[Page 63070]]

 
Wood furniture manufacturing............  Approval...................  pp. 1115 and 1135 of the May 31, 2017
                                                                        submittal, and p. 24 of the State of
                                                                        Colorado Categorical Reasonable
                                                                        Available Control Technology Review for
                                                                        Brewing and Wood Furniture Surface
                                                                        Coating TSD, October 30, 2018, document
                                                                        set 21 (contained within the May 10,
                                                                        2019 submittal).
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Cited materials are contained within the docket for this action.

    In our July 3, 2018 rulemaking, we approved Colorado's 
demonstration of RACT for certain VOC CTG sources \27\ for the 2008 8-
hour ozone standard. Today we are taking action on the RACT 
demonstrations for certain additional VOC CTG, non-CTG VOC, and 
NOX sources and categories. We have reviewed Colorado's new 
and revised VOC and NOX rules for the source categories 
covered by the CTGs, and for major sources of non-CTG VOC and 
NOX sources for the 2008 8-hour ozone NAAQS, and the 
demonstrations submitted by Colorado. Based on this review we propose 
to find that these rules are consistent with the control measures, 
definitions, recordkeeping, and test methods in these CTGs and the CAA, 
and that they satisfy CAA RACT requirements for the categories in 
question.\28\
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    \27\ 83 FR at 31069-31070; see Proposed Rule, Promulgation of 
State Implementation Plan Revisions; Colorado; Attainment 
Demonstration for the 2008 8-Hour Ozone Standard for the Denver 
Metro/North Front Range Nonattainment Area, and Approval of Related 
Revisions, 83 FR 14807, 14814-141815, Tables 5 and 6 (Apr. 6, 2018).
    \28\ See https://www.epa.gov/ground-level-ozone-pollution/ractinformation.
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1. RACT for CTG Sources
    Table 1 contains a list of CTG source categories, EPA reference 
documents, and the corresponding sections of Reg. 7 that fulfill the 
applicable RACT requirements for EPA-issued CTGs.\29\ Colorado's Reg. 7 
contains SIP-approved \30\ and submitted revisions (see Section IV of 
this document); we propose to find that these revisions meet RACT 
requirements for the source categories listed in Table 1.
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    \29\ See EPA's TSD for a full analysis of Colorado's rules as 
they relate to EPA guidelines and available technical information. 
We will be acting on the RACT demonstrations for the Oil and Gas 
2016 CTG source category, the Miscellaneous Metal Products Coatings 
category, and for sources of NOX in the categories for 
process heaters, glass melting furnaces, and pre 2005 turbines in a 
future action.
    \30\ See 76 FR at 47443 and 83 FR at 31069-31070.
    \31\ See p. 1126 of the May 31, 2017 submittal for Colorado's 
RACT demonstration for Metal furniture coatings.
    \32\ See p. 1115 and p. 1135 of the May 31, 2017 submittal, and 
p. 24 of the State of Colorado Categorical Reasonable Available 
Control Technology Review for Brewing and Wood Furniture Surface 
Coating TSD, October 30, 2018, document set 21 (contained within the 
May 10, 2019 submittal).
    \33\ See p. 1116 of the May 31, 2017 submittal.
    \34\ See Colorado's August 4, 2020 letter committing to submit 
to EPA a negative declaration certifying that there are no sources 
in the DMNFR Area above the aerospace CTG applicability threshold 
(contained within the docket). The EPA proposes to conditionally 
approve Colorado's determination that there are no sources in the 
DMNFR Area subject to the aerospace CTG and therefore RACT is 
satisfied for this category. If we finalize our proposed conditional 
approval, Colorado must submit the negative declaration, after state 
notice and public hearing, to EPA within one year of our 
finalization. If Colorado does not submit the negative declaration 
within one year, or if we find Colorado's revisions to be 
incomplete, or we disapprove Colorado's revisions, this conditional 
approval will convert to a disapproval. If any of these occur and 
our conditional approval converts to a disapproval, that will 
constitute a disapproval of a required plan element under part D of 
title I of the Act, which starts an 18-month clock for sanctions, 
see CAA section 179(a)(2), and the two-year clock for a federal 
implementation plan, see CAA section 110(c)(1)(B).

  Table 1--Source Categories, EPA CTG Reference Documents, and Corresponding Sections of Reg. 7 Fulfilling RACT
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                                                                                      Reg. 7 sections fulfilling
      Source category in DMNFR Area         CTG reference  document     Date of CTG              RACT
----------------------------------------------------------------------------------------------------------------
Metal Furniture Coatings \31\...........  Control Techniques                    2007  Sections V and IX (already
                                           Guidelines for Metal                        SIP approved except
                                           Furniture Coatings.                         XI.A.9.a.(ii) proposed
                                                                                       for approval in this
                                                                                       action).
Wood Furniture Manufacturing Operations   Control of Volatile                   1996  Sections V (already SIP
 \32\.                                     Organic Compound                            approved) and IX.O
                                           Emissions from Wood                         (proposed for approval in
                                           Furniture Manufacturing                     this action).
                                           Operations.
Industrial Cleaning Solvents \33\.......  Control Techniques                    2006  Sections V (already SIP
                                           Guidelines for Industrial                   approved) and X (proposed
                                           Cleaning Solvents.                          for approval in this
                                                                                       action).
Aerospace \34\..........................  Control of Volatile                   1997  No sources above the CTG
                                           Organic Compound                            applicability threshold
                                           Emissions from Coating                      in the DMNFR Area
                                           Operations at Aerospace                     (negative declaration
                                           Manufacturing and Rework                    proposed for conditional
                                           Operations.                                 approval in this action).
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    We have reviewed the emission limitations and control requirements 
for the above source categories and compared them against the EPA's CTG 
documents and available technical information in CTG dockets and 
regional RACT determinations. The EPA has also evaluated the submitted 
rules \35\ and has determined that they are consistent with the CAA, 
EPA regulations, and EPA policy. For more information, see the EPA TSD 
prepared in conjunction with this action. Based on the information in 
the record, we propose to find that the corresponding sections in Reg. 
7 provide for the lowest emission limitation through application of 
control techniques that are reasonably available considering 
technological and economic feasibility. Therefore, we propose to find 
that the control requirements for the source categories identified in 
Table 1 are RACT for all affected sources in the DMNFR Area under the 
2008 8-hour ozone NAAQS.
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    \35\ See 83 FR at 31068 and section V of this proposed rule.
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2. RACT for Non-CTG Major Sources
    In Appendix 6-F of the May 31, 2017 submittal, Colorado identified 
a list of major non-CTG VOC and NOX sources

[[Page 63071]]

in the DMNFR Area. The State reviewed its point source inventory to 
verify that major sources of VOC and NOX emissions in the 
NAA are subject to requirements that meet or exceed RACT. For major VOC 
and NOX sources subject to NAA RACT review, Colorado used 
the construction permit thresholds established in the State's Reg. 3 
for determining which emission points to review. Accordingly, emission 
points exceeding two tpy of VOC at a major VOC source and five tpy of 
NOX at a major NOX source, as reported on source 
Air Pollutant Emission Notices, were evaluated. We have reviewed the 
State's May 31, 2017 submittal and find its approach to including these 
sources in the inventory acceptable.
    On November 17, 2016, to satisfy the Moderate RACT SIP requirement 
to establish RACT for all existing major sources of VOC and/or 
NOX in the DMNFR Area, the Commission incorporated by 
reference several New Source Performance Standards (NSPS) and National 
Emission Standards for Hazardous Air Pollutants (NESHAP) 
regulations.\36\ The Division also developed the stationary combustion 
equipment and brewery categorical RACT standards, based on a detailed 
review of the information provided by owners and operators of major 
NOX and VOC sources in the DMNFR Area, an examination of the 
EPA RACT/Best Available Control Technology/Lowest Achievable Emission 
Rate Clearinghouse for similar emission points, and consideration of 
CAA section 182(b) RACT requirements for other ozone nonattainment 
areas. Table 2 contains a list of non-CTG source category EPA reference 
documents and the corresponding sections of Reg. 7 that are proposed 
for approval in this action to fulfill RACT requirements (see Section 
IV of this document).\37\
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    \36\ The EPA previously approved Colorado's rule revisions and 
RACT analyses for VOCs into Colorado's SIP under the 1-hour ozone 
standard. See Final rule, Approval and Promulgation of Air Quality 
Implementation Plans; Colorado; Regulation 7, 60 FR 28055 (May 30, 
1995).
    \37\ See the EPA's TSD for a full analysis of Colorado's rules 
as they relate to EPA guidelines and available technical 
information.

 Table 2--Source Categories, EPA Reference Documents, and Corresponding Sections of Reg. 7 Proposed for Approval
                                                 To Fulfill RACT
----------------------------------------------------------------------------------------------------------------
  Source category in the DMNFR Area    EPA reference documents                               Reg. 7 sections
                 \38\                      (if applicable)            Date of ACT            fulfilling RACT
----------------------------------------------------------------------------------------------------------------
Stationary Internal Combustion         NOX Emissions from       July 1993, Updated       Applicable provisions
 Engines \39\.                          Stationary Internal      September 2000.          in XVI.D. and XIX.A.
                                        Combustion Engines                                (proposed for approval
                                        (EPA-453/R-93-032).                               in this action).
Commercial & Institutional Boilers     NOX Emissions from       March 1994.............  Applicable provisions
 \40\.                                  Industrial, Commercial                            in XVI.D. (proposed
                                        and Institutional                                 for approval in this
                                        Boilers (EPA-453/R-94-                            action).
                                        022).
Stationary Combustion Turbines \41\..  NOX Emissions from       January 1993...........  Applicable provisions
                                        Stationary Gas                                    in XVI.D. (proposed
                                        Turbines (EPA-453/R-93-                           for approval in this
                                        007).                                             action, except
                                                                                          XVI.D.4.b.(i) which
                                                                                          will be acted on at a
                                                                                          later date).
Utility Boilers \42\.................  NOX Emissions from       March 1994.............  Applicable provisions
                                        Utility Boilers (EPA-                             in XVI.D. (proposed
                                        453/R-94-023).                                    for approval in this
                                                                                          action).
Cement Manufacturing \43\............  NOX Emissions from       March 1994/September     XIX.B. (proposed for
                                        Cement Manufacturing     2000.                    approval in this
                                        (EPA-453/R-94-004) and                            action).
                                        NOX Control
                                        Technologies for the
                                        Cement Industry: Final
                                        Report (EPA-457/R-00-
                                        002)..
Landfill Gas Flares \44\.............  .......................  .......................  XIX.C. (proposed for
                                                                                          approval in this
                                                                                          action).
Brewing Operations \45\..............  .......................  .......................  XX. (proposed for
                                                                                          approval in this
                                                                                          action).
----------------------------------------------------------------------------------------------------------------

     
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    \38\ Colorado's major source RACT analysis can be found on pp. 
1119-1120 and 1142-1149 of the May 31, 2017 submittal and the 
Technical Support Document for Reasonably Available Control 
Technology for Major Sources, November 17, 2016 (pp. 2990-3273 of 
May 31, 2017 submittal).
    \39\ See pp. 21-26 of the Categorical Reasonably Available 
Control Technology Review for Boilers, Turbines, Engines, Glass Melt 
Furnaces and Aggregate Kilns and Major NOX Sources in the 
Denver Metro/North Front Range Ozone Nonattainment Area, July 2018. 
Contained within the May 10, 2019 submittal for combustion equipment 
(document set 25).
    \40\ See id. pp. 9-15.
    \41\ See id. pp. 16-21.
    \42\ See id. pp. 9-15.
    \43\ See May 31, 2017 submittal at 1145; Technical Support 
Document for Reasonably Available Control Technology for Major 
Sources, at 3005 (Nov. 17, 2016) (contained in the May 10, 2017 
submittal).
    \44\ See id. at 3015-3016.
    \45\ See State of Colorado Categorical Reasonable Available 
Control Technology Review for Brewing and Wood Furniture Surface 
Coating TSD, document set 21, at 5-24 (Oct. 30, 2018) (contained in 
the May 10, 2019 submittal).
---------------------------------------------------------------------------

    We have reviewed the emission limitations and control requirements 
for the source categories in Table 2 and compared them against EPA's 
ACT documents, available technical information, and guidelines. The EPA 
has also evaluated the submitted rules \46\ and has determined that 
they are consistent with the CAA, EPA regulations, and EPA policy. For 
more information, see the EPA TSD prepared in conjunction with this 
action. Based on the information in the record, we propose to find that 
the corresponding sections in Reg. 7 provide for the lowest emission 
limitation through application of control techniques that are 
reasonably available considering technological and economic 
feasibility. Therefore, we propose to find that, with the noted 
exceptions, the control requirements for the source categories 
identified in Table 2 are RACT for all affected sources in the DMNFR 
Area under the 2008 8-hour ozone NAAQS. We also propose to find that 
for VOC RACT requirements at major non-CTG VOC sources, Colorado has 
RACT-level controls in place for the DMNFR Area under the 2008 8-hour 
ozone standard. We are not finalizing our RACT determination for major 
sources of NOX in this document because we have requested 
additional analyses from Colorado for older turbines and process 
heaters.
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    \46\ See 83 FR at 31068 and section V of this proposed rule.

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[[Page 63072]]

VI. EPA's Evaluation of SIP Control Measures in Reg. 7

    We evaluated Colorado's May 31, 2017, May 14, 2018, and May 10, 
2019 submittals regarding revisions to the State's Reg. 7 to meet RACT 
requirements for various source categories. Revisions to Reg. 7 include 
emission control requirements for surface coating operations, use of 
cleaning solvents, oil and gas operations, stationary and portable 
combustion equipment, major sources of VOC and/or NOX in the 
ozone NAA, and breweries. The revisions establish RACT requirements for 
certain CTG categories and emission points at major sources of VOC and 
NOX in the DMNFR Area. Reg. 7 revisions also add 
incorporation by reference dates to rules and reference methods; and 
correct typographical, grammatical, and formatting errors. For ease of 
review, Colorado submitted the full text of Reg. 7 as SIP revisions 
(with the exception of provisions designated ``State Only''). The EPA 
is only seeking comment on Colorado's proposed substantive changes to 
the SIP-approved version of Reg. 7, which are described below. We are 
not seeking comment on incorporation into the SIP of the revised 
portions of the regulation that were previously approved into the SIP 
and have not been substantively modified by the State as part of any of 
these submittals.
    As noted above, Colorado designated various parts of Reg. 7 ``State 
Only,'' and in Section I.A.1.c indicated that sections designated State 
Only are not federally enforceable. The EPA concludes that provisions 
designated State Only have not been submitted for EPA approval, but for 
informational purposes. Hence, the EPA is not proposing to act on the 
portions of Reg. 7 designated State Only, and this proposed rule does 
not discuss them further except as relevant to discussion of the 
portions of the regulation that Colorado intended to be federally 
enforceable.

A. Evaluation

1. May 31, 2017 SIP Submittal
    The State's May 31, 2017 SIP submittal contains amendments to Reg. 
7 that were not acted on in our July 3, 2018 rulemaking.\47\ We propose 
to approve the changes included in Colorado's May 31, 2017 submittal, 
as identified in Table 4.\48\ Below, we describe in detail Colorado's 
proposed revisions and the basis for our proposed approval of them.
---------------------------------------------------------------------------

    \47\ 83 FR at 31068.
    \48\ All other sections of Reg. 7 addressed in the May 31, 2017 
submission have been superseded by the State's May 14, 2018 and May 
10, 2019 submissions. The EPA is not acting on the superseded 
earlier submissions.
---------------------------------------------------------------------------

a. Section X
    Section X regulates VOC emissions from and establishes RACT for the 
use of cleaning solvents. Changes to Sections X, X.A.1, X.A.2.b.- j., 
X.B.1.d.(ii), and X.D.1.a.(i) include clarification of the 
applicability of Section X, addition of an effective date for Section X 
requirements, addition of definitions for terms used in industrial 
cleaning solvent operations, and minor clerical \49\ revisions that do 
not affect the substance of the requirements.
---------------------------------------------------------------------------

    \49\ When we describe changes as clerical in this proposed 
action, we are referring to changes like section renumbering; 
alphabetizing of definitions; minor grammatical, editorial, and 
typographical revisions; and changes in capitalization.
---------------------------------------------------------------------------

    Section X.E. addresses VOC emissions from industrial cleaning 
solvent operations. Section X.E.1 sets forth control requirements for 
owners and operators of industrial cleaning solvent operations with 
uncontrolled and non-exempt VOC emissions of three tons per year or 
more. These owners and operators must limit the VOC content of cleaning 
solvents to less than or equal to 0.42 lb of VOC/gal (50 grams VOC/
liter), limit the composite partial vapor pressure of cleaning solvent 
to 8 millimeters of mercury (mmHg) at 20 degrees Celsius (68 degrees 
Fahrenheit), and reduce VOC emissions with an emission control system 
having a control efficiency of 90% or greater. Section X.E.2. adds work 
practice requirements to reduce VOC emissions from fugitive sources, 
while Section X.E.3. contains monitoring, recordkeeping, and reporting 
requirements to demonstrate compliance with the control requirements in 
Section X.E. Section X.E.4.contains exemptions from the requirements in 
X.E. We are proposing to approve the exemptions in X.E.4., X.E.4.b., 
X.E.4.b.(i)-(xi), X.E.4.c., and X.E.4.c.(i)-(ii) from the May 31, 2017 
SIP submittal. All other exemptions in Section X.E. have been 
superseded by the May 10, 2019 submittal.
    We propose to find that the provisions are consistent with CAA 
requirements and CTGs, and that they strengthen the SIP, and therefore 
we propose to approve the changes in Section X.
b. Section XVI
    Section XVI specifies emission control requirements for stationary 
and portable combustion equipment. Section XVI.D.\50\ adds a combustion 
adjustment requirement for individual pieces of combustion equipment at 
major sources of NOX in Section XVI.D. The requirements in 
Section XVI.D.\51\ apply to boilers, duct burners, process heaters, 
stationary combustion turbines and stationary reciprocating internal 
combustion engines that have uncontrolled actual NOX 
emissions equal to or greater than 5 tpy that existed at major sources 
of NOX as of June 3, 2016. Sections XVI.D.2.a-d include 
inspection and adjustment requirements for boilers, process heaters, 
duct burners, stationary combustion turbines and stationary internal 
combustion engines. Section XVI.D.2.e requires owners and operators to 
operate and maintain equipment subject to Section XVI.D. consistent 
with manufacturer's specifications or good engineering and maintenance 
practices. Section XVI.D.2.f outlines combustion adjustment frequency 
requirements. Section XVI.D.4 sets forth alternative options to the 
requirements in Sections XVI.D.2.a-e and XVI.D.3.a, including 
conducting combustion process adjustments according to manufacturer's 
recommended procedures and schedules, and conducting tune-ups or 
adjustments according to schedules and procedures of applicable NSPS or 
NESHAPs.\52\
---------------------------------------------------------------------------

    \50\ Renumbered to XVI.D.6.b. in May 10, 2019 submittal.
    \51\ Sections XVI.D.1, XVI.D.1(a)-(e), and XVI.D.3. are 
superseded by the May 10, 2019 submittal.
    \52\ See also p. 3082 of the May 31, 2017 submittal (contained 
within the docket).
---------------------------------------------------------------------------

    We propose to find that the provisions in Section XVI.D are 
consistent with CAA requirements, and that they strengthen the SIP. 
Therefore, and for the reasons explained above, we propose to approve 
the changes in Section XVI.
c. Section XIX
    Section XIX establishes RACT requirements for emission points at 
certain major sources of VOC and NOX in the DMNFR Area. We 
are proposing approval of Sections XIX.D, XIX.F., and XIX.G. from the 
May 31, 2017 submittal. All other parts of Section XIX have been 
superseded by subsequent submittals. Section XIX.D sets forth emission 
limits and monitoring, recordkeeping, and reporting (MRR) requirements 
for major sources of stationary internal combustion engines. Sections 
XIX.F. and XIX.G. establish requirements for certain major sources to 
meet RACT.\53\
---------------------------------------------------------------------------

    \53\ See the TSD associated with this action for a detailed RACT 
analysis associated with these revisions.
---------------------------------------------------------------------------

    We propose to find that the provisions in Section XIX strengthen 
the SIP, are consistent with CAA requirements, and establish RACT 
requirements for certain

[[Page 63073]]

major sources by incorporating federal regulations. We therefore 
propose to approve the changes in Section XIX.
2. May 14, 2018 SIP Submittal
    The State's May 14, 2018 SIP submittal contains amendments to Reg. 
7 Sections XII and XVIII to meet RACT for oil and gas sources covered 
by EPA's 2016 Oil and Gas CTG. The submittal also includes clarifying 
revisions and typographical, grammatical and formatting corrections 
throughout Reg. 7. We propose to approve the typographical, grammatical 
and formatting corrections made to Sections I, II, III, V, VI, VII, 
VIII, IX, X, XI, XIII, XIV, XV and XVI with Colorado's May 14, 2018 
submittal. The revisions in this section are clerical in nature and do 
not affect the substance of the requirements. Therefore, we propose to 
approve the changes.
    We are not acting on any submitted changes to Sections XII or XVII. 
These revisions will be acted on at a later date.
3. May 10, 2019 SIP Submittal (Combustion Equipment)
    The State's May 10, 2019 SIP submittal contains amendments to Reg. 
7, Sections XVI and XIX, establishing categorical and source specific 
RACT requirements for major sources of VOC and/or NOX in the 
DMNFR Area. We propose to approve the changes made to Section XVI 
except for Section XVI.D.4.b.(i) and XVI.D.4.d. which we will act on at 
a later date. We also propose to approve the changes made to Section 
XIX with Colorado's May 10, 2019 submittal.
    Below, we describe in detail Colorado's proposed revisions and the 
basis for our proposed approval of such revisions.
a. Section XVI
    As previously stated, Section XVI specifies emission control 
requirements for stationary and portable combustion equipment. One 
revision to Section XVI updates the title to the Section. This revision 
is clerical in nature and does not affect the substance of the 
requirement.
    The other revisions to Section XVI that we are considering in this 
action concern Section XVI.D., which establishes requirements for major 
sources of NOX within the DMNFR Area. Section XVI.D.1. 
(``Applicability'') establishes the geographic scope of the rule and 
the sources that are subject to Section XVI.D. requirements. Owners and 
operators of stationary combustion equipment, as defined in Section 
XVI.D.3.n., located at a major source of NOX as of June 3, 
2016 in the DMNFR Area, must comply with the requirements of XVI.D. 
unless exempted under XVI.D.2. We propose to find that this is 
consistent with CAA requirements.
    Section XVI.D.2. outlines exemptions from control requirements in 
Section XVI.D. Section XVI.D.2.a. contains a 20% capacity factor 
exemption for boilers and a 10% capacity factor exemption for 
stationary combustion turbines and compression ignition reciprocating 
internal combustion engines. The capacity factor exemptions consolidate 
a number of limited-use exemptions that were analyzed and considered by 
the Division to limit the complexity of the categorical rules and to 
adequately accommodate technical and cost concerns for limited-use 
equipment. Once stationary combustion equipment no longer qualifies for 
any exemption, the owner or operator must comply with the applicable 
requirements of Section XVI.D.
    Stationary combustion equipment that meets one of the exemptions 
contained in Section XVI.D.2. is not required to comply with the 
emission limitations, the compliance demonstration requirements and the 
related recordkeeping and reporting requirements in Sections XVI.D.4., 
XVI.D.5., XVI.D.7. and XVI.D.8., except for XVI.D.7.g, which requires a 
source that qualifies for an exemption under Section XVI.D.2. to 
maintain records demonstrating that an exemption applies. All 
stationary combustion equipment is subject to some level of 
recordkeeping and may also be subject to combustion process adjustment 
requirements in Section XVI.D.6. The technical support document in the 
docket for this action has more details on the justification for these 
exemptions. These exemptions are consistent with exemptions allowed in 
other state federally enforceable rules,\54\ and meet CAA requirements. 
Accordingly, we propose to approve these revisions.
---------------------------------------------------------------------------

    \54\ See, e.g., Wisconsin Control of Nitrogen Compound Emissions 
rule, Wis. Admin. Code NR Sec.  428.08 (2020).
---------------------------------------------------------------------------

    Section XVI.D.3. contains definitions specific to Section XVI.D. 
The definitions are clear, straightforward, and accurate.
    Section XVI.D.4. establishes NOX emission rate limits by 
source category applicable to emission units operating above the 
applicability threshold. The source categories, emission limitations, 
and Reg. 7 rule citation are presented in Table 3. The emission limits 
contained in the rule are a 30-day rolling average requirement 
applicable on a year-round basis. A unit subject to an emission 
limitation must demonstrate compliance by October 1, 2021. The 
following emission limits established in Section XVI.D.4. are 
consistent with CAA requirements applicable to the various categories 
for which ACT documents have been issued and with more recent state and 
federal NOX control programs.

     Table 3--Affected Sources and NOX Emission Requirements for Boilers, Engines, Turbines, and Lightweight
                                        Aggregate Kilns in the DMNFR Area
----------------------------------------------------------------------------------------------------------------
                                          NOX emission
          Source category             limitation  (30 day     Additional information            Citation
                                        rolling average)
----------------------------------------------------------------------------------------------------------------
Boilers \55\.......................  0.2 lbs/MMBtu........  Gaseous and liquid fuel-    XVI.D.4.a.
                                                             fired with design heat
                                                             input >=100 MMBtu/hr.
Reciprocating Internal Combustion    9.0 g/bhp-hr.........  Maximum design power        XVI.D.4.e.
 Engines \56\.                                               output equal to or
                                                             greater than 500
                                                             horsepower.
Turbines \57\......................  Applicable NOX limits  Maximum design heat input   XVI.D.b.(ii).
                                      in 40 CFR part 60,     capacity equal to or
                                      subpart KKKK.          greater than 10 MMBtu/hr.
                                                             For turbines that
                                                             commenced construction,
                                                             modification, or
                                                             reconstruction after Feb.
                                                             18, 2005.
Lightweight aggregate kilns \58\...  56.6 lbs NOX per hour  ..........................  XVI.D.4.c.
----------------------------------------------------------------------------------------------------------------

[[Page 63074]]

    By October 1, 2021, owners or operators must determine compliance 
with emission limitations in Section XVI.D.4. in accordance with one of 
the methods in Section XVI.D.5. Section XVI.D.5. requires most sources 
subject to emission limitations to demonstrate compliance using 
continuous emissions monitoring. For electric generating unit sources, 
this monitoring is based on 40 CFR part 75 methods, and for industrial 
sources monitoring is based on 40 CFR part 60 methods. For a few source 
categories with low variability in operations or emission rates, 
compliance is demonstrated by periodic stack testing. The emission 
monitoring requirements are consistent with existing State and EPA 
programs.
---------------------------------------------------------------------------

    \55\ See Table 4 in Colorado's ``Categorical RACT Review for 
Boilers, Turbines, Engines, Glass Melt Furnaces and Aggregate Kilns 
at Major NOX Sources in the DMNFR NAA'' TSD (July 2018) 
for a list of boilers potentially subject to XVI.D.4.a.
    \56\ See Table 11 in Colorado's TSD (July 2018) for a list of 
compression ignition engines potentially subject to XVI.D.e.
    \57\ See Table 9 in Colorado's TSD (July 2018) for a list of 
turbines potentially subject to XVI.D.e.
    \58\ There is one lightweight aggregate kiln at a major source 
of NOX in the DMNFR NAA. RACT for this kiln is analyzed 
on p. 28-30 in Colorado's TSD (July 2018).
---------------------------------------------------------------------------

    Colorado's May 10, 2019 submittal renumbers the combustion process 
adjustment requirements in XVI.D.6. (previously Sections XVI.D.1. and 
2); clarifies the applicability of the requirements in XVI.D.6.a.; 
moves definitions for boilers, duct burners, process heaters, 
stationary combustion turbines and stational internal combustion 
engines to Section XVI.D.3.; and revises section references in Section 
XVI.D.6.b.(vi)(B). These revisions do not affect the substance of the 
Section XVI.D. requirements we propose to approve from the May 31, 2017 
submittal. We therefore propose to approve these changes.
    Sections XVI.D.7. and 8 require all affected unit owners and 
operators to maintain records for five years and submit reports to the 
Division. These records and reports will be used to determine 
compliance, instances of noncompliance, and to determine if exempt 
units continue to remain exempt by staying below specific thresholds. 
These provisions are acceptable.
b. Section XIX
    Section XIX establishes RACT requirements for emission points at 
major sources of VOC and NOX in the DMNFR Area. We are 
proposing approval of the renumbering in Section XIX.A from the May 10, 
2019 submittal.\59\
---------------------------------------------------------------------------

    \59\ Sections XIX.A.-C. were originally submitted to EPA on May 
31, 2017 and listed by name major sources of VOC and/or 
NOX, required owners or operators of major sources to 
submit RACT analyses to the Division by December 31, 2017, and set a 
compliance date for turbines to meet emission limits and MRR 
requirements. The EPA did not act on Section XIX with our April 6, 
2018 (83 FR 14807) rulemaking. Colorado's May 10, 2019 submission 
deletes Sections XIX.A-C, but since the provisions were never 
approved into the SIP, we are taking no action on the deleted 
portions of the submission.
---------------------------------------------------------------------------

4. May 10, 2019 SIP Submittal (Brewing Activities and Wood Furniture 
Surface Coating Operations)
    The State's May 10, 2019 SIP submittal contains amendments to Reg. 
7, Sections I, II, VI, VII, IX, X, XII, XIII, XVI, XVII, XVIII and XX. 
The revisions include RACT requirements in Section XX for brewing 
related activities at major VOC sources and RACT requirements in 
Section IX for wood furniture surface coating operations. The submittal 
also includes incorporation by reference dates to rules and reference 
methods in Sections II, VI, VIII, IX, X, XII, XIII, XVI and XVII. 
Lastly, the submittal contains SIP cleanup revisions in Section I, adds 
a surface coating work practice in Section IX, and revises an exemption 
in the industrial cleaning solvent requirements in Section X. 
Typographical, grammatical and formatting corrections were also made. 
We propose to approve these changes with Colorado's May 10, 2019 
submittal, except for the revisions in Sections XII. and XVIII, which 
will be acted on at a later date.
a. Sections II, VI, VIII, IX, X, XIII, XV, XVI, XVII, XIX
    The changes made in these sections include revisions to specific 
rule or reference methods incorporated by reference to add applicable 
citation dates. These changes strengthen the SIP. Other changes 
throughout these sections are clerical in nature and do not affect the 
substance of the requirements.
b. Section I
    Section I sets forth the applicability of Reg. 7. Sections I.B.2.f. 
and I.B.2.g. were adopted by the Commission in 1990 and include one-
time reporting requirements concerning source emissions and RACT for 
sources existing as of 1989. The provisions were not an ongoing 
reporting requirement potentially necessary for monitoring compliance 
with applicable emissions limits. Since these one-time requirements 
have passed and Colorado's major stationary sources are now subject to 
RACT requirements in Reg. 7, as adopted by the Commission through 2018, 
the Commission removed provisions in I.B.2.f and I.B.2.g. Removal of 
these provisions does not remove or modify any control measures, and 
therefore does not affect emissions nor interfere with attainment or 
reasonable further progress. Where information in the Sections I.B.2.f. 
and I.B.2.g. reports informed RACT requirements under Section II.C., 
sources remain subject to applicable RACT requirements and any emission 
reporting requirements as addressed by the emission statement rule last 
approved by the EPA in 2015.\60\ The removal of the one-time reporting 
requirements in I.B.2.f. and I.B.2.g. is reasonable and does not relax 
the SIP or otherwise interfere with CAA requirements.
---------------------------------------------------------------------------

    \60\ See 80 FR 50205 (Aug. 19, 2015).
---------------------------------------------------------------------------

    Section I.E. deletes language regarding IBR materials available for 
public inspection. The deletion is reasonable because the same language 
is contained in the paragraph under ``Outline of Regulation'' and has 
updated instructions on how to obtain materials electronically.
c. Section IX
    Section IX regulates VOC emissions and establishes RACT 
requirements for surface coatings operations. Section IX.A.9. sets 
forth required and prohibited acts for owners and operators of sources 
of VOCs subject to Section IX. Based on an EPA recommendation, the 
Commission adopted good air pollution control practices and coating 
application methods in IX.A.9.a.(ii). We propose to find the provision 
consistent with CTG recommendations and that it strengthens the SIP.
    Section IX.O. establishes new rules for limiting VOC emissions from 
wood furniture coating operations. These emission reductions are 
accomplished through limiting VOC content of coatings/materials used, 
establishing requirements for application equipment, and work practices 
and recordkeeping requirements.
    Section IX.O.2. provides that the rules in section IX.O. apply to 
wood furniture manufacturing operations, including related cleaning 
activities, that have the potential to emit 25 tons or more per year of 
VOCs and that are located in the DMNFR Area. Section IX.O.3. sets forth 
control requirements for owners and operators of wood manufacturing 
operations. Requirements include VOC content limits for topcoats, 
sealers, and strippable booth coatings. Section IX.O.4. adds work 
practice requirements to minimize material usage and overspray, manage 
cleanup of wastes, inspect for leaks and provide for the collection of 
cleaning and washoff solvents and the use of conventional air spray 
guns. Section IX.O.5. contains

[[Page 63075]]

reporting requirements to demonstrate compliance with the control 
requirements in Section IX.O.\61\ A detailed evaluation of Section 
IX.O. is in the TSD for this action. We propose to find that the 
provisions in Section IX.O. are consistent with CAA requirements and 
CTGs, and that they strengthen the SIP. For the reasons previously 
explained, we propose to approve the changes in Section IX.
---------------------------------------------------------------------------

    \61\ Operators and owners of wood furniture manufacturing 
operations subject to Section IX.O. are also subject to requirements 
in Section IX.A.1.-IX.A.9.
---------------------------------------------------------------------------

d. Section X
    As previously discussed, Section X. regulates VOC emissions from 
the use of cleaning solvents. Section X.E.4. establishes exemptions 
from the requirements in Section X.E. for industrial cleaning solvent 
operations. The Commission removed the general exemption in X.E.4.a.(i) 
and (ii) originally submitted on May 31, 2017 and revised the exemption 
in X.E.4.a. to apply only to industrial cleaning solvent operations 
that are subject to another federally enforceable section of Reg. 7 
that establishes RACT. The provisions in X.E.4.a. are reasonable and 
consistent with CAA requirements. We therefore propose to approve the 
changes in this section.
e. Section XX
    Section XX regulates VOC emissions from major source brewery and 
brewery-related operations. Section XX.A. establishes new rules for 
limiting emissions from breweries and brewery-related operations at 
major sources of VOCs as of June 3, 2016. These reductions are 
accomplished through process line emission limits, packaging operations 
work practices, wastewater management and treatment and recordkeeping 
requirements.
    Section XX applies to owners or operators of breweries that existed 
at major sources of VOC in the DMNFR Area as of July 3, 2016. A 
brewery, as defined in Section XX.A.3.a., includes brewhouse, 
fermentation, aging and packaging operations. Brewery-related 
operations include operations that support the production of malt 
beverages such as wastewater management, container manufacturing and 
ethanol distillation. Section XX.A.4. sets forth emissions limitations 
of 6 percent process loss across all packaging operations in a calendar 
month and 4 percent process loss on a 12-month rolling average during 
packaging operations. Section XX.A.5. establishes packaging operation 
work practices including performance metrics to reduce product loss, 
operator training and packaging equipment to reduce container breakage 
and product loss. Section XX.A.6. includes requirements for wastewater 
management and treatment for land application of wastewater. Section 
XX.A.7. requires owners or operators to keep records of production, 
pollution prevention activities and wastewater to demonstrate 
compliance with the operational requirements. A detailed evaluation of 
Section XX.A. is in the TSD for this action. We propose to find that 
the provisions in Section XX.A. are consistent with CAA and RACT 
requirements, and that they strengthen the SIP.
    For the reasons previously explained, we propose to approve the 
changes in Section XX.A.

VII. Proposed Action

    For the reasons expressed above, the EPA proposes to approve 
revisions to Sections I, II, III, V, VI, VII, VIII, IX, X, XI, XIII, 
XIV, XV, XVI, XVII, XIX and XX of Reg. 7 from the State's May 31, 2017, 
May 14, 2018 and May 10, 2019 submittals as shown in Table 4, except 
for those revisions we are not acting on as represented in Table 5. We 
are proposing to approve Colorado's determination that the above rules 
constitute RACT for the specific categories addressed in Tables 1 and 
2, except for aerospace, for which we are proposing conditional 
approval.
    Finally, the EPA proposes to correct regulatory text and IBR 
published in the Federal Register on July 3, 2018.\62\
---------------------------------------------------------------------------

    \62\ 83 FR 31068.
---------------------------------------------------------------------------

    A comprehensive summary of the revisions in Colorado's Reg. 7 
organized by EPA's proposed rule action, reason for proposed ``no 
action'' and submittal date are provided in Tables 4 and 5.

 Table 4--List of Colorado Revisions to Reg. 7 That the EPA Proposes To
                                 Approve
 
     Revised Sections in May 31, 2017, May 14, 2018 and May 10, 2019
                    Submittals Proposed for Approval
 
May 31, 2017 submittal:
    X., X.A.1, X.A.2.b.-j., X.B.1.d.(ii), X.D.1.a.(i), X.E., X.E.1.,
     X.E.1.a.-c., X.E.2., X.E.2.a.-c., X.E.3., X.E.3.a., X.E.3.a.(i)-
     (iv), X.E.3.b., X.E.3.b.(i)-(iii), X.E.3.b.(iii)(A)-(B), X.E.4.,
     X.E.4.b., X.E.4.b.(i)-(xi), X.E.4.c., X.E.4.c.(i)-(ii), XVI.D.,
     XVI.D.2., XVI.D.2.a.-f.(ii), XVI.D.4., XVI.D.4.a.-b., XIX., XIX.D.,
     XIX.D.1-12., XIX.F. and G.
May 14, 2018 submittal:
    I.A.1.c., I.B.1.c., I.B.2.c., I.B.2.e., I.B.2.g., I.B.2.h., II.A.9.,
     II.A.10., II.D.2., III.C., V.B., VI.B.1.a., VI.B.1.b.,
     VI.B.2.a.(i)(C), VI.B.2.a.(i)(E), VI.B.2.a.(iii)(B),
     VI.B.2.a.(iii)(C), VI.B.2.c.(i)(B)(1), VI.B.2.c.(i)(B)(2),
     VI.B.2.c.(ii)(B), VI.B.2.c.(ii)(B)(1), VI.B.2.c.(ii)(C)(2),
     VI.B.2.c.(iii)(A), VI.B.2.c.(iii)(B)(1), VI.B.3.a., VI.B.3.b.,
     VI.B.3.b.(i), VI.B.3.h., VI.C.1., VI.C.2.a., VI.C.2.b., VI.C.2.c.,
     VI.C.3.a.-c., VI.C.3.c.(iii), VI.C.3.d.-f., VI.D.1.a.-b.,
     VI.D.2.a., VI.D.2.a.(i)-(ii), VI.D.2.a.(ii)(A)-(C), VI.D.2.b.(i),
     VI.D.2.b.(ii)(B), VI.D.3.a., VI.D.3.b., VI.D.4.a.-VI.D.4.c.,
     VI.D.4.c.(ii), VI.D.4.d.(i), VI.D.4.d.(iv), VI.D.4.e., VII.A.2.,
     VII.B.-C., VIII.A.2.a.(i)-(iii), VIII.A.2.a.(iii)(A), VIII.B.6.,
     VIII.C.1., VIII.C.1.b., VIII.C.2.a.(i)-(v), VIII.C.2.a.(vi)(A)-(B),
     VIII.C.2.c.(iii), VIII.C.4.a.(i)(A), VIII.C.4.a.(i)(A)(6),
     VIII.C.4.a.(i)(B), VIII.C.4.a.(i)(E), VIII.C.4.a.(ii)-(iii),
     VIII.C.4.b.(i)(J), VIII.C.4.c.(ii), IX.A.3.c.-e., IX.A.5.,
     IX.A.5.a.-d., IX.A.5.e., IX.A.6.a.-b., IX.A.8.b., IX.A.9.a.(1),
     IX.A.10.b., IX.A.11., IX.A.12.a., IX.A.12.a.(iv), IX.A.12.a.(vi),
     IX.A.12.a.(ix), IX.A.12.a.(x), IX.B.2.-5., IX.C.2., IX.D.2.,
     IX.E.2., IX.F.2., IX.G.2., IX.H.1.b., IX.H.2., IX.I.2., IX.J.1.a.,
     IX.J.2., IX.K.1., IX.K.2., IX.L.1.a., IX.L.1.b.(i)-(ii), IX.L.1.c.,
     IX.L.2.a.-c., IX.L.2.c.(iii)-(vi), IX.M.2., IX.M.3.a.,
     IX.N.3.a.(i)(A), IX.N.4.a.(ii), IX.N.5.-6., X.A.5., X.B.1.d.(ii),
     X.C.1.c.(i), X.C.2.d., X.E.3.b.(i), X.E.4.a.(i), XI.A.1., XI.B.3.,
     XI.C., XIII.A.1.a, XIII.A.3.a.(iii), XIII.A.3.a.(v)-(vi),
     XIII.A.3.c.-d., XIII.A.4., XIII.B.5.a.-b., XIII.B.5.c., XIV.C.1.,
     XV.B.1.d., XV.B.2.a., XVI.C., XVI.C.1., XVI.C.3.-4.,
     XVII.E.3.a.(i), XVII.E.3.a.(i)(A)-(C).
May 10, 2019 submittal--RACT for combustion sources:
    XVI., XVI.D., XVI.D.1.-XVI.D.4.a.(ii), XVI.4.b.(ii)-(iii),
     XVI.D.4.c., XVI.D.4.e.-XVI.D.5.a.(iv), XVI.D.6. (renumbering),
     XVI.D.6.a., XVI.D.6.b.-XVI.D.6.b.(vi)(B) (renumbering), XVI.D.6.c.,
     XVI.D.6.c.(i)-(ii) (renumbering), XVI.D.7.-XVI.D.8.b.(i), XIX.A.
     (renumbering).
May 10, 2019 submittal--RACT for brewing related activities and wood
 furniture surface coating operations:
    I.B.2.f.-g., I.E., II.A.17., VI.B.2.a.(i)(D), VI.B.3.i., VI.C.2.d.-
     e., VI.D.3.c., VI.D.4.d.(v), VIII.A.2.a.(iii)(B), VIII.B.7.,
     VIII.C.3., IX.A.1., IX.A.3.a., IX.A.9.a.(i), IX.A.9.a.(ii),
     IX.A.10.b., IX.A.11., IX.L.2.c.(vi), IX.N.7., IX.O.-IX.O.5.a.(v),
     X.D.2.a., X.E.3.b.(iii)(A)-(B), X.E.4.a., X.E.4.c.-(ii),
     XIII.B.5.c.(iii)(A)-(B), XV.B.1.b., XVI.D.6.b.(vi)(A),
     XVI.D.6.c.(ii), XVI.D.7.f.(iii), XVII.E.3.a.(i)(B), XIX.B.-C.
     (renumbering), XX.-XX.A.7.c.
 

[[Page 63076]]

            Table 5--List of Colorado Revisions to Reg. 7 That EPA Is Proposing To Take No Action on
----------------------------------------------------------------------------------------------------------------
                                                                       Reason for proposed ``No Action''
                                                              --------------------------------------------------
                       Revised section                          Superseded by    Revision to be   Revision never
                                                                 May 10, 2019    made in future   approved into
                                                                  submittal        rulemaking        the SIP
----------------------------------------------------------------------------------------------------------------
May 31, 2017 submittal:
    X.E.4.a..................................................               X   ...............  ...............
    X.E.4.a.(i)-(ii).........................................               X   ...............  ...............
    XVI.D.1..................................................               X   ...............  ...............
    XVI.D.1.A.-e.............................................               X   ...............  ...............
    XVI.D.3..................................................               X   ...............  ...............
    XVI.D.3.a.-c.............................................               X   ...............  ...............
    XV.I.D.4.c...............................................               X   ...............  ...............
    XIX.A.-C.................................................               X   ...............  ...............
    XIX.E....................................................               X   ...............  ...............
May 14, 2018 submittal:
    II.B.....................................................  ...............               X   ...............
    Section XII..............................................  ...............               X   ...............
    XVI.D.2.a.(iv)...........................................               X   ...............  ...............
    XVI.D.3.a.(ii)-(iii).....................................               X   ...............  ...............
    XVI.D.4..................................................               X   ...............  ...............
    Section XVIII............................................  ...............               X   ...............
May 10, 2019 submittal--RACT for combustion sources:
    XVI.D.4.b.(i)............................................  ...............               X   ...............
    XVI.D.4.d................................................  ...............               X   ...............
May 10, 2019 submittal--RACT for brewing related activities
 and wood furniture surface coating operations:
    X.E.4.a.(i)-(ii).........................................  ...............  ...............               X
    XIX.B....................................................  ...............  ...............               X
    Section XII..............................................  ...............               X   ...............
    Section XVIII............................................  ...............               X   ...............
----------------------------------------------------------------------------------------------------------------

VIII. Incorporation by Reference

    In this document, the EPA is proposing to include regulatory text 
in an EPA final rule that includes incorporation by reference. In 
accordance with requirements of 1 CFR 51.5, the EPA is proposing to 
incorporate by reference Colorado AQCC regulation 7 pertaining to the 
control of ozone via ozone precursors and control of hydrocarbons vial 
oil and gas emissions discussed in section VI. of this preamble. The 
EPA has made, and will continue to make, these materials generally 
available through www.regulations.gov and at the EPA Region 8 Office 
(please contact the person identified in the FOR FURTHER INFORMATION 
CONTACT section of this preamble for more information).

IX. Statutory and Executive Order Reviews

    Under the CAA, the Administrator is required to approve a SIP 
submittal that complies with the provisions of the Act and applicable 
Federal regulations. 42 U.S.C. 7410(k); 40 CFR 52.02(a). Thus, in 
reviewing SIP submittals, the EPA's role is to approve state choices, 
provided that they meet the criteria of the CAA. Accordingly, this 
action merely proposes to approve state law as meeting Federal 
requirements and does not impose additional requirements beyond those 
imposed by state law. For that reason, this action:
     Is not a ``significant regulatory action'' subject to 
review by the Office of Management and Budget under Executive Orders 
12866 (58 FR 51735, October 4, 1993) and 13563 (76 FR 3821, January 21, 
2011);
     Is not an Executive Order 13771 (82 FR 9339, February 2, 
2017) regulatory action because SIP approvals are exempted under 
Executive Order 12866;
     Does not impose an information collection burden under the 
provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.);
     Is certified as not having a significant economic impact 
on a substantial number of small entities under the Regulatory 
Flexibility Act (5 U.S.C. 601 et seq.);
     Does not contain any unfunded mandate or significantly or 
uniquely affect small governments, as described in the Unfunded 
Mandates Reform Act of 1995 (Pub. L. 104-4);
     Does not have Federalism implications as specified in 
Executive Order 13132 (64 FR 43255, August 10, 1999);
     Is not an economically significant regulatory action based 
on health or safety risks subject to Executive Order 13045 (62 FR 
19885, April 23, 1997);
     Is not a significant regulatory action subject to 
Executive Order 13211 (66 FR 28355, May 22, 2001);
     Is not subject to requirements of section 12(d) of the 
National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272 
note) because application of those requirements would be inconsistent 
with the CAA; and
     Does not provide EPA with the discretionary authority to 
address, as appropriate, disproportionate human health or environmental 
effects, using practicable and legally permissible methods, under 
Executive Order 12898 (59 FR 7629, February 16, 1994).

In addition, the SIP is not approved to apply on any Indian reservation 
land or in any other area where EPA or an Indian tribe has demonstrated 
that a tribe has jurisdiction. In those areas of Indian country, the 
proposed rule does not have tribal implications and will not impose 
substantial direct costs on tribal governments or preempt tribal law as 
specified by Executive Order 13175 (65 FR 67249, November 9, 2000).

List of Subjects in 40 CFR Part 52

    Environmental protection, Air pollution control, Carbon monoxide, 
Greenhouse gases, Incorporation by reference, Intergovernmental 
relations, Lead, Nitrogen dioxide, Ozone, Particulate matter, Reporting 
and

[[Page 63077]]

recordkeeping requirements, Sulfur oxides, Volatile organic compounds.

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

    Dated: September 4, 2020.
Gregory Sopkin,
Regional Administrator, EPA Region 8.
[FR Doc. 2020-20099 Filed 10-5-20; 8:45 am]
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