[Federal Register Volume 88, Number 45 (Wednesday, March 8, 2023)]
[Rules and Regulations]
[Pages 14269-14276]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-04507]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R07-OAR-2022-0746; FRL-10184-02-R7]


Air Plan Approval; MO; Restriction of Visible Air Contaminant 
Emissions

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: The Environmental Protection Agency (EPA) is taking final 
action to approve revisions to the Missouri State Implementation Plan 
(SIP) received on November 29, 2016, and March 7, 2019. The revisions 
were submitted by Missouri in response to a finding of substantial 
inadequacy and SIP call published on June 12, 2015, for a provision in 
the Missouri SIP related to excess emissions during startup, shutdown, 
and malfunction (SSM) events. In the submissions, Missouri requests to 
revise a regulation related to restriction of emissions of visible air 
contaminants. The revisions to the rule include removing a statement 
from the compliance and performance testing provisions that does not 
meet Clean Air Act (CAA) requirements, adding exemptions for emission 
units regulated by stricter federal and state regulations or that do 
not have the capability of exceeding the emission limits of the rule, 
adding an alternative test method and making other administrative 
changes. Approval of these revisions will ensure consistency between 
state and federally approved rules.

DATES: This final rule is effective on April 7, 2023.

ADDRESSES: The EPA has established a docket for this action under 
Docket ID No. EPA-R07-OAR-2022-0746 to www.regulations.gov. All 
documents in the docket are listed on the www.regulations.gov website. 
Although listed in the index, some information is not publicly 
available, i.e., CBI or other information whose disclosure is 
restricted by statute. Certain other material, such as copyrighted 
material, is not placed on the internet and will be publicly available 
only in hard copy form. Publicly available docket materials are 
available through www.regulations.gov or please contact the person 
identified in the FOR FURTHER INFORMATION CONTACT section for 
additional information.

FOR FURTHER INFORMATION CONTACT: Ashley Keas, Environmental Protection 
Agency, Region 7 Office, Air Quality Planning Branch, 11201 Renner 
Boulevard, Lenexa, Kansas 66219; telephone number: (913) 551-7629; 
email address: [email protected].

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

Table of Contents

I. Background
II. What is being addressed in this document?
III. Have the requirements for approval of a SIP revision been met?
IV. The EPA's Responses to Comments
V. What action is the EPA taking?
VI. Environmental Justice Considerations
VII. Incorporation by Reference
VIII. Statutory and Executive Order Reviews

I. Background

    On September 12, 2022, EPA proposed to approve SIP revisions 
submitted by the State of Missouri, on

[[Page 14270]]

November 29, 2016, and March 7, 2019 (87 FR 55739). In that proposal, 
we also proposed to determine that the SIP revision corrects the 
deficiency with respect to Missouri that we identified in our June 12, 
2015 action entitled ``State Implementation Plans: Response to Petition 
for Rulemaking; Restatement and Update of EPA's SSM Policy Applicable 
to SIPs; Findings of Substantial Inadequacy; and SIP Calls to Amend 
Provisions Applying to Excess Emissions During Periods of Startup, 
Shutdown, and Malfunction'' (``2015 SSM SIP call'') (80 FR 33839, June 
12, 2015). The reasons for our proposed approval and determination are 
stated in the proposed action (87 FR 55739, September 12, 2022) and are 
not restated here. The public comment period for our proposed approval 
and determination ended on October 12, 2022. During the comment period, 
EPA received comments from one entity and responds to those comments in 
section IV of this document.

II. What is being addressed in this document?

    The EPA is taking final action to approve Missouri's revisions to 
10 CSR 10-6.220, Restriction of Emissions of Visible Air Contaminants, 
in the Missouri SIP. The EPA received two SIP revision submissions 
related to this state rule from the Missouri Department of Natural 
Resources (MoDNR) on November 29, 2016, and March 7, 2019. On September 
12, 2022, the EPA published a notice of proposed rulemaking (NPRM) 
proposing to approve Missouri's submissions (87 FR 55739). The full 
text of Missouri's requested rule changes as well as EPA's analysis of 
the changes can be found in the NPRM and technical support document 
(TSD), which is included in the docket for this action.
    In its November 29, 2016, submission, MoDNR requested to remove the 
provision that was identified by EPA as being substantially inadequate 
to meet CAA requirements in EPA's 2015 SSM SIP Action. As explained in 
our NPRM, EPA finds that removal of this provision is consistent with 
EPA's policy outlined in the 2015 SSM SIP Action and sufficiently 
addresses the deficiencies identified by the 2015 SSM SIP Call.
    In addition to the removal of the identified SSM deficiency, MoDNR, 
in both the 2016 and 2019 submissions, also requested revisions related 
to opacity monitoring requirements and exemptions from the opacity 
limits and recordkeeping and reporting requirements of 10 CSR 10-6.220 
for certain source types. Specifically, MoDNR exempted specific, 
limited, emission units regulated by stricter federal and state 
regulations. MoDNR also provided an exemption for certain emission 
units that do not have the capability of exceeding the emission limits 
of the rule.
    Missouri provided a demonstration pursuant to CAA section 110(l) to 
ensure the rule revisions, including the added exemptions, do not 
interfere with any applicable requirement concerning attainment and 
reasonable further progress, or any other applicable requirement of the 
Act. Specifically, Missouri demonstrates that sources being exempted 
from the state opacity limit generally are either subject to an 
equivalent or more stringent limit in federal or state law or are 
physically incapable of exceeding the state opacity limit and therefore 
exempting these sources from the state opacity limit will not result in 
a net emissions change. Based on EPA's review of Missouri's section 
110(l) demonstration and our analysis of these changes as discussed 
below and more fully described in the NPRM and TSD in the docket for 
this rule, EPA finds these revisions will result in no net emissions 
change and no change to status quo air quality. For these reasons, EPA 
finds the revisions will not interfere with attainment or maintenance 
of the National Ambient Air Quality Standards (NAAQS) or other CAA 
requirements consistent with CAA section 110(l).
    MoDNR also added an alternative test method and made other 
administrative wording changes such as adding rule specific 
definitions. For the reasons explained in the NPRM, TSD, and this 
document, EPA finds these edits are consistent with CAA requirements, 
therefore EPA is approving the revisions to 10 CSR 10-6.220 as 
requested by Missouri.

III. Have the requirements for approval of a SIP revision been met?

    The State submission has met the public notice requirements for SIP 
submissions in accordance with 40 CFR 51.102. The submission also 
satisfied the completeness criteria of 40 CFR part 51, appendix V. The 
State provided public notice on the November 29, 2016, SIP revision 
from June 1, 2016, to August 4, 2016, and held a public hearing on July 
28, 2016. During the public comment period, the State received seven 
comments from five sources, consisting primarily of supportive or 
clarifying comments from industry groups. The State addresses the 
comments in its submittal included in the docket for this proposal. The 
State provided public notice on the March 7, 2019, SIP revision from 
August 1, 2018, to October 4, 2018, and held a public hearing on 
September 27, 2018. During the public comment period, the State 
received nine comments, seven of which were from EPA. The State 
addresses the comments in its submittal. Further discussion of the 
state responses to comments received is included in the TSD and the 
state submittal documents in the docket. In addition, as explained 
above and in the TSD, the revision meets the substantive SIP 
requirements of the CAA, including section 110 and implementing 
regulations.

IV. The EPA's Responses to Comments

    The public comment period on the EPA's proposed rule opened 
September 12, 2022, the date of its publication in the Federal Register 
and closed on October 12, 2022. During this period, EPA received one 
comment letter from the Sierra Club.
    Comment 1: The commenter supports EPA's proposed approval of 
Missouri's removal of 10 CSR 10-6.220(3)(C) as satisfying EPA's 2015 
SSM SIP Call to Missouri and requests EPA to act quickly to approval 
removal of this provision from the Missouri SIP.
    Response 1: EPA appreciates the supportive comment and as part of 
today's action is finalizing approval of removal of this deficient 
provision consistent with the commenter's request.
    Comment 2: The commenter expresses concern with Missouri's 
expansion of the exemption for internal combustion engines. The 
commenter states EPA previously expressed concern with this change and 
argues the state did not adequately support the change nor address 
EPA's concerns. The commenter argues EPA's rationale for proposed 
approval of this expanded exemption is insufficient. Specifically, the 
commenter argues reliance on federal mobile source regulations is 
insufficient because the federal regulations are outdated and only 
apply to new engines. The commenter asserts that old, dirty engines 
continue to pollute along roads and highways, disproportionately 
affecting people of color. The commenter then references the State of 
Nevada's opacity standard as an example state opacity program that 
could limit visible emissions from certain vehicles. For these reasons, 
the commenter requests EPA not approve the proposed exemption for 
internal combustion engines or that EPA conditionally approve the 
revisions, provided the state removes the internal combustion exemption 
no later than one year after EPA's approval.
    Response 2: First, in response to the commenter's claim that 
Missouri did

[[Page 14271]]

not address EPA's comment on this exemption, this is in reference to 
Missouri's 2019 SIP revision. The change to this exemption was included 
in Missouri's 2016 SIP revision. Therefore, in Missouri's 2019 SIP 
revision, as referenced by commenter, Missouri explained that this 
exemption was not being changed, public comment was not solicited for 
this change and therefore Missouri did not make changes as a result of 
EPA's comment on this provision in the 2019 SIP revision. When this 
exemption was revised and proposed for public comment during Missouri's 
2016 SIP revision, EPA did comment requesting Missouri add supportive 
information to the TSD, which Missouri responded to and addressed as 
part of the 2016 SIP revision. EPA discussed this information in the 
proposed rule and associated TSD included in the docket for this 
action.
    As fully described in EPA's proposed rule and TSD in the docket for 
this action and as referenced by the commenter, the opacity limits 
currently in the Missouri SIP only apply to non-stationary internal 
combustion (IC) engines in the St. Louis and Kansas City metropolitan 
areas and the requested revision would expand the exemption to all 
internal combustion engines throughout the state. As the commenter 
references, the state explains the limits were first adopted in the 
1960's to address emissions from older and less efficient vehicles and 
fuels. Since that time, EPA has enacted more stringent requirements and 
limits for newer model year vehicles and cleaner fuels and the vehicle 
population has continued to turnover to newer and cleaner vehicles.
    As further explained in the NPRM and TSD, EPA's approval of this 
revision is consistent with CAA section 110(l) because the revision 
will not increase net emissions of criteria pollutants or their 
precursors. The primary basis for this determination is that the 
sources subject to the state opacity limit, for which Missouri is 
expanding this exemption in section (1)(A), continue to be subject to 
more stringent federal requirements. Therefore, sources that are in 
compliance with the more stringent federal requirements will not exceed 
the state opacity limit. Therefore, those sources subject to the 
federal requirements will not have a net increase in emissions. EPA's 
judgment that such SIP revisions do not ``interfere'' with attainment 
of the NAAQS is consistent with the plain and ordinary meaning of the 
statute, its structure, and EPA's past practice in conducting analyses 
under section 7410(l). The CAA, 42 U.S.C. 7410(l), provides, in 
relevant part that ``[t]he Administrator shall not approve a revision 
of a plan if the revision would interfere with any applicable 
requirement concerning attainment.'' For over fifteen years, EPA has 
interpreted section 7410(l) as permitting approval of a SIP revision as 
long as ``emissions in the air are not increased,'' thereby preserving 
``status quo air quality.'' Kentucky Resources Council, Inc. v. EPA, 
467 F.3d 986, 991, 996 (6th Cir. 2006); see also Indiana v. EPA, 796 
F.3d 803, 806 (7th Cir. 2015) (same); Alabama Environmental Council v. 
EPA, 711 F.3d 1277, 1292-93 (11th Cir. 2013) (same); Galveston-Houston 
Association for Smog Prevention v. EPA, 289 F. Appendix 745, 754 (5th 
Cir. 2008) (hereinafter ``GHASP'') (same). EPA implements this 
interpretation of section 7410(l) by approving SIP revisions if they do 
not result in a change to status quo air quality and thereby will not 
interfere with attainment or other CAA requirements. In doing so, ``the 
level of rigor needed for any CAA [section 7410(l)] demonstration will 
vary depending on the nature and circumstances of the revision.'' See 
EPA final rule 86 FR 48908, 48910; 86 FR 60172. Where EPA anticipates 
that a SIP revision may increase emissions, it typically requires that 
a state either (1) submit air quality analysis to demonstrate that the 
revision would not interfere with any applicable requirement or (2) 
substitute equivalent or greater emissions reductions in order to 
preserve status quo air quality. See 86 FR 48910; 86 FR 60172; see also 
Ky. Res. Council, 467 F.3d at 995 (denying petition challenging under 
section 7410(l) SIP revision approval where the revision would not 
increase net emissions). However, where the SIP revision does not relax 
or remove any pollution controls--and therefore does not involve an 
increase in emissions--such requirements are unnecessary, because there 
is no reason to believe that such a SIP revision will interfere with 
any applicable requirement concerning attainment, or, in other words, 
there is no reason to believe that such a SIP revision would make air 
quality worse. See 86 FR 48911; 86 FR 60173; see also WildEarth 
Guardians v. EPA, 759 F.3d 1064, 1074 (9th Cir. 2014). EPA applied the 
same interpretation of section 7410(l) in proposing to approve 
Missouri's SIP revision. Specifically, because the expanded exemption 
in section (1)(A) does relax the stringency of state rule 10-6.220, 
Missouri and EPA evaluated whether this expanded exemption would result 
in a net change to emissions or change in status quo air quality. As 
described previously, EPA agrees with Missouri's assertion that due to 
the continued implementation of the current federal requirements, which 
are the controlling requirements for this source sector rather than the 
state opacity limit, this revision will not result in increased net 
emissions or a change to status quo air quality.
    To the commenter's point that the EPA's currently implemented 
heavy-duty diesel regulations are outdated, the currently implemented 
heavy-duty vehicle regulations established stringent PM emission 
standards beginning with model year 2007 vehicles and engines.\1\ 
Therefore, all new heavy-duty vehicles and engines sold since then have 
been required to comply with those stringent emission standards for PM. 
On December 20, 2022, EPA finalized more stringent emission standards 
for PM from heavy-duty vehicles and engines, beginning with model year 
2027.\2\ Similarly, EPA has issued stringent PM emissions standards for 
various types of nonroad equipment and engines such as construction 
equipment and locomotives.\3\ EPA is not obligated to issue federal 
regulations on a specific time schedule and further, the state cannot 
be held responsible for EPA's regulations addressing emissions from 
this source sector becoming outdated in the commenter's opinion. The 
CAA provides EPA with the authority to regulate emissions from mobile 
source emissions, such as those from cars, trucks and various types of 
nonroad equipment and engines.\4\ Congress has generally preempted 
states from setting mobile source emissions standards. Jensen Family 
Farms, Inc. v. Monterey Bay Unified Air Pollution Control Dist., 644 
F.3d 934, 938 (9th Cir. 2011) (citing 42 U.S.C. 7543(a)). States such 
as Missouri do not have the authority to regulate mobile source 
emissions or fuels directly and per Missouri law may not adopt rules 
that are more stringent than federal law. In its demonstration, the 
state also referred to its vehicle emissions inspections in the St. 
Louis Metropolitan Area to ensure light-duty vehicle emissions control 
equipment is functioning properly (10 CSR 10-5.381

[[Page 14272]]

On-Board Diagnostics Motor Vehicle Emission Inspection), and 
regulations limiting heavy duty diesel vehicle idling in both Kansas 
City and St. Louis Metropolitan Areas (10 CSR 10-2.385 and 5.385 
Control of Heavy Duty Diesel Vehicle Idling Emissions).
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    \1\ See 66 FR 5002, January 18, 2001.
    \2\ See 88 FR 4296, January 24, 2023.
    \3\ For example, Control of Emissions of Air Pollution From 
Nonroad Diesel Engines and Fuel (69 FR 38958, June 29, 2004) and 
Control of Emissions of Air Pollution from Locomotive Engines and 
Marine Compression-Ignition Engines Less Than 30 Liters per 
Cylinder; Republication (73 FR 37096, June 30, 2008).
    \4\ See CAA sections 202(a) and 213(a).
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    Additionally, there are many voluntary programs being implemented 
by EPA and states that are targeted at replacing older diesel engines 
with new cleaner engines or retrofitting older diesel engines to reduce 
particulate matter emissions. For example, through the Diesel Emissions 
Reduction Act (DERA) EPA continues to provide millions of dollars of 
grant funding per year to state, local, and tribal air agencies as well 
as directly to nonprofit organizations through competitive grant 
opportunities to replace older diesel engines with new cleaner 
models.\5\ Specifically, previously awarded national competitive DERA 
grants included projects to replace school buses, trucks, and 
commercial marine engines with new cleaner versions in both of these 
metropolitan areas.\6\ Another example of a program that targets 
replacement of older diesel engines include the Volkswagen trust fund, 
which accounts for a major investment in Missouri, up to $41 million by 
2027 awarded to Missouri-specific projects to mitigate emissions from 
diesel engines in Missouri.\7\ While these are voluntary programs and 
therefore not federally enforceable, and EPA is thus not relying on 
these programs for its section 110(l) analysis, the replacements and 
upgrades funded through these programs have played a major role and 
will continue to result in real reductions of emissions in local 
communities including the Kansas City and St. Louis metropolitan areas.
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    \5\ EPA posts previously awarded grants to the national DERA 
website, https://www.epa.gov/dera.
    \6\ See listing of nationally awarded competitive grants sorted 
by state and local organization at https://www.epa.gov/dera/national-dera-awarded-grants. For example, St. Louis (Regional) 
Clean Cities, Mid America Regional Council, and Metropolitan Energy 
Center have previously managed nationally awarded DERA grants in the 
St. Louis and Kansas City metropolitan areas, respectively.
    \7\ https://dnr.mo.gov/air/what-were-doing/volkswagen-trust-funds/awarded-projects.
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    To the commenter's point about Nevada's opacity program, EPA agrees 
that states have this discretion to enforce opacity limits either 
through regularly required inspections or through roadside pullover 
programs in their state, however it is not in the scope of this 
rulemaking action to prescribe how Missouri could potentially alter its 
rulemaking and enforcement of opacity limits in the future. At issue, 
is the question of whether this rule revision will result in a net 
emissions increase. As described in the proposed rule and TSD, EPA 
finds that the information provided by the state and available to EPA 
supports the conclusion that this revision will not result in a net 
emissions increase and therefore will not interfere with attainment or 
other CAA requirements.
    Finally, to the commenter's point about disproportionate impacts 
from older diesel engines on people of color, in section I.C. of the 
final rule ``Control of Air Pollution from New Motor Vehicles: Heavy-
Duty Engine and Vehicle Standards'' EPA states that, ``Our 
consideration of environmental justice literature indicates that people 
of color and people with low income are disproportionately exposed to 
elevated concentrations of many pollutants in close proximity to major 
roadways.'' \8\ EPA includes additional discussion of the available 
literature in sections II.C and II.D. of that final rule.\9\
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    \8\ See 88 FR 4310, January 24, 2023.
    \9\ See Id.
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    For these reasons, EPA continues to find that this rule revision to 
expand the exemption to all IC engines in the state will result in no 
net emissions change in these areas and therefore will not interfere 
with attainment or maintenance of the NAAQS or any other CAA 
requirements.
    To further respond to the commenter's concern, EPA reviewed 
available emissions data for these areas, from the most recent complete 
national emissions inventory (NEI) for 2017. In that inventory, we 
evaluated what percentage of the total particulate matter 
(PM10) emissions in these areas are from the mobile source 
sector and more specifically from onroad mobile sources. All emissions 
data referenced here is included in the spreadsheet titled, ``2017 NEI 
MO PM Emissions Data'' included in the docket for this action. The key 
comparisons as shown in Table 1 are contained in the summary tab while 
the other tabs contain the full datasets.

 Table 1--2017 NEI PM10 Emissions for the Missouri Portions of the St. Louis and Kansas City Metropolitan Areas
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                                          PM10 emissions (tons per year)               Percent of total PM10
                                 ------------------------------------------------            emissions
   Missouri metropolitan area                                                    -------------------------------
                                       Total        All mobile     Onroad mobile    All mobile     Onroad mobile
                                                      sources         sources         sources         sources
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Kansas City.....................         137,622           1,755           1,248             1.3             0.9
St. Louis.......................          89,020           2,661           1,931             3.0             2.2
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    Table 1 shows the total PM10 emissions for the Missouri 
portion of each metropolitan area as well as the percentage 
attributable to the mobile source sector and the percentage 
attributable to onroad mobile sources. The mobile source category 
includes onroad, nonroad, airport, watercraft and rail source 
categories. The mobile source category accounts for 1.3% and 3.0% of 
total PM emissions in the Missouri portions of Kansas City and St. 
Louis, respectively. The onroad mobile source category includes sources 
such as heavy duty trucks, transit and school buses. And onroad mobile 
sources account for 0.9% and 2.2% of total PM emissions in the Missouri 
portions of Kansas City and St. Louis, respectively. As shown in the 
table, emissions from onroad mobile sources, including diesel engines, 
account for a relatively small percentage of overall PM emissions in 
these areas.
    As discussed above and as more fully described in the NPRM and TSD, 
in reviewing Missouri's requested rule revisions, EPA evaluated all 
available relevant information including information provided by the 
state. Based on EPA's review of that information, EPA finds that 
Missouri's revision to section (1)(A) of state rule 10-6.220, would not 
result in a net change to emissions or a change in status quo air 
quality and therefore will not interfere

[[Page 14273]]

with attainment of the NAAQS or any other applicable requirements, 
consistent with CAA section 110(l).
    Comment 3: The commenter expresses concern with Missouri's addition 
of an exemption for emission units burning certain fuels. The commenter 
questions whether AP-42 factors accurately estimate emissions from 
these fuels. The commenter then argues that while these fuels may 
generally have lower visible emissions, they may have the potential to 
emit levels of other pollutants that contribute to opacity.
    Response 3: First, with respect to the added section (1)(L) in 10-
6.220, EPA continues to find that the units burning the listed fuels 
are not physically capable of exceeding the state rule opacity limit as 
demonstrated by Missouri. For this reason, this rule revision will 
result in no net emissions change and subsequently no change to status 
quo air quality. Therefore, as explained in response to comment 2, will 
not interfere with attainment or maintenance or any other CAA 
requirement consistent with CAA section 110(l). Further, the EPA 
disagrees with the commenter's assertion that EPA's ``Compilation of 
Air Pollutant Emissions Factors,'' also known as AP-42, does not 
accurately estimate emissions associated with combustion of these 
fuels. As referenced by the commenter, Missouri includes the 
calculation used to estimate potential emissions associated with 
combustion of these fuels and references the appropriate sections of 
the publicly available AP-42 information maintained by EPA. Through 
these calculations, the state demonstrates that units combusting the 
fuels covered by this provision are not physically capable of emitting 
greater than the 20% opacity limits of the state rule. Further, the 
state calculations show that the maximum expected percent opacity 
emissions are at least 25% below the 20% state rule opacity limit 
(i.e., cannot exceed 15% opacity) and in most cases at least 50% below 
the 20% state rule opacity limit (i.e., cannot exceed 10% opacity) to 
allow for a reasonable margin of safety in the estimations. For these 
reasons, EPA continues to find that exempting units that combust only 
the gaseous fuels listed by Missouri in section (1)(L) of state rule 
10-6.220 will result in no net emissions change and therefore will not 
interfere with attainment or maintenance of the NAAQS or any other CAA 
requirements, consistent with CAA section 110(l).
    Comment 4: The commenter expresses concern with Missouri's added 
exemption for units subject to an equivalent or more restrictive 
emission limit under 10 CSR 10-6.075 or any federally enforceable 
permit. The commenter argues that Missouri did not satisfactorily 
support this added exemption with a demonstration for EPA to review. 
The commenter further argues that this exemption violates the Act's SIP 
revision requirements and EPA's SSM SIP Call policy by allowing sources 
to be exempt on a case-by-case basis outside the SIP revision process 
which the commenter argues could also limit the public's ability to 
participate in the public review process. For these reasons, the 
commenter requests EPA not approve this exemption or alternately 
conditionally approve, provided Missouri removes this added exemption 
no later than one year after EPA's approval.
    Response 4: As referenced in Missouri's submittals, the statewide 
opacity rule was consolidated from several area-specific rules which 
were originally promulgated in the late 1960's and early 1970's, prior 
to the enactment of the Clean Air Act. The opacity limits established 
in 10 CSR 10-6.220 were carried over from these early rules and apply 
to all sources of visible emissions in Missouri, including a vast array 
of air pollution sources. These air pollution sources are also subject 
to federal or state regulations with stricter emission limits and more 
comprehensive requirements. This has created redundancies in air 
pollution regulation and duplicative requirements. Missouri's basis for 
revising this rule was to remove the less stringent requirements on 
sources and thereby remove duplicative monitoring, reporting and 
recordkeeping (MRR) requirements to allow sources to focus on 
compliance with the more stringent requirements that are not being 
impacted by this rulemaking. Contrary to commenter's assertion, 
Missouri did provide support for this rule revision in the technical 
support document included in the submittal for the 2019 revision on 
page 12 of 38 in the document with Docket ID # EPA-R07-OAR-2022-0746-
0008. The state explains that State rule 10 CSR 10-6.075 Maximum 
Achievable Control Technology Regulations incorporates by reference the 
delegable federal subparts of 40 CFR part 63 National Emission 
Standards for Hazardous Air Pollutants for Source Categories. These 
federal Maximum Achievable Control Technology (MACT) regulations are 
source-specific and establish detailed requirements tailored to 
numerous processes and operations emitting hazardous air pollutants. 
The state goes on to note that many sources and emission units subject 
to stringent opacity and PM limits under 40 CFR part 63 are also 
subject to 10 CSR 10-6.220 due to the broad applicability of the 
opacity rule. The state further explains that since the opacity limits 
in 10 CSR 10-6.220 are less stringent than those specified in numerous 
subparts incorporated in 10 CSR 10-6.075, it is appropriate to add an 
exemption for emission units subject to an equivalent or stricter 
emission limit under 10 CSR 10-6.075 or a federally enforceable permit 
condition. The state concludes by stating the addition of this 
exemption to the opacity rule will eliminate regulatory overlap, 
simplify the Title V permit application process, streamline permit 
conditions, and decrease permit review time.
    As the commenter points out, Missouri provided a thorough 
demonstration correlating PM and opacity emissions to show limits for 
certain sources are indeed stricter than the state rule limit and EPA 
reviewed this demonstration as explained in the proposed rule and 
associated TSD. This correlation demonstration was necessary because 
the state was comparing different types of emission limits, 
specifically opacity and PM limits. For the ``equivalent or more 
restrictive emission limit'' that Missouri includes in this provision, 
EPA interprets this as a direct comparison between limits involving the 
same pollutant and same unit of measure. Specifically, EPA interprets 
this revision as allowing an exemption from the state rule opacity 
limits only when a limit is very clearly equivalent or more stringent 
in all cases such that the limits would in fact be duplicitous and that 
such an exemption be accompanied by a clear comparison demonstrating 
the stringency of the limits in order to support an exemption from the 
less stringent limit. This evaluation of stringency must clearly show 
that when the source complies with the more stringent requirement, the 
source can be considered to be in compliance with the less stringent 
requirement. Further, as discussed in the NPRM, in order for a limit to 
be equivalent or more stringent than the state opacity limit it must be 
continuous in nature and not allow for exemptions for periods of SSM 
given EPA's approval through this action to remove section (3)(C) from 
state rule 10-6.220 as discussed in our response to comment 1.
    With EPA's approval and Missouri's implementation of this 
provision, sources would still be subject to the more stringent limit 
but no longer be subject to the less stringent limit and its

[[Page 14274]]

associated MRR requirements. And as stated in our proposed rule and TSD 
and as referenced by the commenter, exemption from a less stringent 
limit while continuing to be required to comply with an equivalent or 
more stringent limit would indeed result in no net emissions change and 
subsequently no change to status quo air quality as a result of the 
rule revision. Further, the only material change would be the removal 
of the MRR requirements associated with the less stringent limit 
thereby removing unnecessary duplicative requirements.
    Missouri also added provisions in sections (1)(J) and (1)(M) of 10-
6.220 which, as further discussed in EPA's TSD included in the docket 
for this action, exempt sources from the state opacity rule that are 
also subject to specific National Emissions Standards for Hazardous Air 
Pollutants (NESHAP) regulations which require the covered sources to 
comply with more stringent emissions limits than the state opacity 
limits. Missouri's reference to state rule 10-6.075 in section (1)(P) 
of 10-6.220 is intended to encompass the other MACT and NESHAP 
regulations that Missouri has accepted delegation for through this 
state rule. Those MACT and NESHAP regulations incorporated by reference 
in 10-6.075 include emissions limits set by EPA for certain source 
categories. Similar to the provisions in sections (1)(J) and (1)(M), 
section (1)(P) relies on EPA's more stringent requirements for the 
relevant source categories in order to be exempt from the state opacity 
limit provided it is indeed shown to be less stringent. This intention 
is further supported by Missouri's response to comments from EPA 
(comment and response #2 on page 26 of 38 in Missouri's 2019 submittal 
in the docket for this action). Specifically, the state's intention in 
adding this exemption for sources subject to 10-6.075, and the MACT and 
NESHAP requirements that are incorporated by reference through this 
state rule, is to exempt emissions units subject to equivalent or more 
stringent emission limits contained in these federal regulations under 
40 CFR part 63 for which Missouri has accepted delegation without 
explicitly listing each NESHAP or federal regulation as a separate 
provision under the applicability section in 10-6.220. This method of 
referring to 10-6.075 where the MACT and NESHAP requirements are 
incorporated by reference, and for which Missouri has accepted 
delegation, is a reasonable way of streamlining requirements for 
impacted sources while maintaining that the most stringent or 
controlling limit and associated MRR requirements continue to apply.
    For these reasons, EPA continues to find there will be no net 
emissions change and subsequently no change to status quo air quality 
associated with this revision and therefore, as described at length in 
our response to comment 2, this revision would not interfere with 
attainment or other CAA requirements.
    Second, EPA disagrees with the commenter's assertion that approval 
of this exemption would be inconsistent with the Act's SIP revision 
requirements and EPA's SSM SIP Call policy. First, EPA's action on 
Missouri delegations and acceptance of enforcement authority for 
federal regulations, including 10 CSR 10-6.075, is also subject to 40 
CFR 51.102 requiring EPA's public notice and comment process. EPA last 
granted Missouri's delegation authority for 10 CSR 10-6.075, among 
other rules, on June 1, 2018 (83 FR 25382).
    In order for additional source categories subject to MACT and 
NESHAP regulations that are not already included in 10-6.075 to be 
exempted from the opacity limits of 10-6.220, Missouri must update 10-
6.075 through the normal state rulemaking process, including public 
notice and comment and submittal to EPA for action. Only after EPA's 
delegation to the state of the implementation and enforcement authority 
of the relevant requirements for any newly added source categories 
could these sources then be eligible for exemption from the opacity 
limits of 10-6.220 pending the evaluation of stringency showed the 
delegated limits incorporated in 10-6.075 were indeed equivalent or 
more stringent than the opacity limits of 10-6.220. Delegation confers 
primary responsibility for implementation and enforcement of the listed 
standards to the respective state air agency. However, EPA also retains 
the concurrent authority to enforce the standards so granting 
delegation to a state does not affect EPA's ability to enforce a 
standard nor does it prohibit the ability for citizens to file lawsuits 
under Clean Air Act Sec.  304, 42 U.S.C. 7604. Additionally, through 
the second clause of this provision, Missouri clarifies this revision 
is limited to federally enforceable permits which are subject to 
Missouri's SIP approved permitting program which also includes public 
notice and comment requirements. Further, EPA has an oversight role in 
permitting and has the ability to review and influence via comment 
permits which will be relied upon to exempt a source from the state 
rule opacity limit. EPA also retains authority and discretion pursuant 
to CAA section 110(k)(5) to require states to revise previously 
approved SIP provisions if EPA becomes aware that they do not meet CAA 
requirements. Finally, this revision does not violate EPA's SSM SIP 
Policy because as described in EPA's NPRM and above, in order to be 
considered equivalent or more stringent the emissions limit must be 
continuous in nature and not include exemptions for periods of SSM.
    For these reasons, EPA continues to find there will be no net 
emissions change associated with this revision and for the reasons 
described in Response to Comment 2, the revision would therefore not 
interfere with attainment or maintenance of the NAAQS or any other CAA 
requirements, consistent with CAA section 110(l).

V. What action is the EPA taking?

    The EPA is taking final action to approve the revisions to 10 CSR 
10-6.220 as requested by Missouri in submissions dated November 29, 
2016 and March 7, 2019.

VI. Environmental Justice Considerations

    Executive Order 12898 (Federal Actions To Address Environmental 
Justice in Minority Populations and Low-Income Populations, 59 FR 7629, 
Feb. 16, 1994) directs Federal agencies to identify and address 
``disproportionately high and adverse human health or environmental 
effects'' of their actions on minority populations and low-income 
populations to the greatest extent practicable and permitted by law. 
The EPA defines environmental justice (EJ) as ``the fair treatment and 
meaningful involvement of all people regardless of race, color, 
national origin, or income with respect to the development, 
implementation, and enforcement of environmental laws, regulations, and 
policies.'' The EPA further defines the term fair treatment to mean 
that ``no group of people should bear a disproportionate burden of 
environmental harms and risks, including those resulting from the 
negative environmental consequences of industrial, governmental, and 
commercial operations or programs and policies.''
    The state did not evaluate environmental justice considerations as 
part of its SIP submittal; the CAA and applicable implementing 
regulations neither prohibit nor require such an evaluation. While EPA 
did not perform an area-specific EJ analysis for purposes of this 
action, due to the nature of the action being taken here, i.e., to 
remove an exemption for excess emissions

[[Page 14275]]

during periods of SSM and add exemptions for sources subject to 
equivalent or more stringent limits, as explained in this preamble, the 
preamble to the proposed rule, and the technical support document in 
this docket, this action is expected to have a neutral to positive 
impact on air quality. Consideration of EJ is not required as part of 
this action, and there is no information in the record inconsistent 
with the stated goal of E.O. 12898 of achieving environmental justice 
for people of color, low-income populations, and Indigenous peoples.
    This action approves revisions to a Missouri state rule concerning 
visible emissions. As explained in this preamble, the preamble to the 
proposed rule, and technical support document, EPA finds the revisions 
will result in no net emissions change and subsequently no change to 
status quo air quality. Therefore, we expect that this action will not 
interfere with attainment or maintenance of the NAAQS, reasonable 
further progress, or other CAA requirements. For these reasons, this 
action is not expected to have a disproportionately high or adverse 
human health or environmental effects on a particular group of people.

VII. Incorporation by Reference

    In this document, the EPA is finalizing regulatory text that 
includes incorporation by reference. In accordance with requirements of 
1 CFR 51.5, the EPA is finalizing the incorporation by reference of the 
Missouri Regulation, 10 CSR 10-6.220, state effective March 30, 2019, 
which regulates visible air contaminant emissions from certain sources 
throughout the state. The EPA has made, and will continue to make, 
these materials generally available through www.regulations.gov and at 
the EPA Region 7 Office (please contact the person identified in the 
FOR FURTHER INFORMATION CONTACT section of this preamble for more 
information).

VIII. Statutory and Executive Order Reviews

    Under the Clean Air Act (CAA), the Administrator is required to 
approve a SIP submission 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 submissions, the EPA's role is to approve state 
choices, provided that they meet the criteria of the CAA. Accordingly, 
this action merely approves state law as meeting Federal requirements 
and does not impose additional requirements beyond those 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);
     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 the National Technology 
Transfer and Advancement Act (NTTA) because this rulemaking does not 
involve technical standards; and
     This action does not have disproportionately high and 
adverse human health or environmental effects on minority populations, 
low-income populations and/or indigenous peoples, as specified in 
Executive Order 12898 (59 FR 7629, February 16, 1994). The basis for 
this determination is contained in section VI of this action, 
``Environmental Justice Considerations.''
     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 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).
     This action is subject to the Congressional Review Act, 
and EPA will submit a rule report to each House of the Congress and to 
the Comptroller General of the United States. This action is not a 
``major rule'' as defined by 5 U.S.C. 804(2).
     Under section 307(b)(1) of the Clean Air Act, petitions 
for judicial review of this action must be filed in the United States 
Court of Appeals for the appropriate circuit by May 8, 2023. Filing a 
petition for reconsideration by the Administrator of this final rule 
does not affect the finality of this action for the purposes of 
judicial review nor does it extend the time within which a petition for 
judicial review may be filed, and shall not postpone the effectiveness 
of such rule or action. This action may not be challenged later in 
proceedings to enforce its requirements (see section 307(b)(2)).

List of Subjects in 40 CFR Part 52

    Environmental protection, Air pollution control, Carbon monoxide, 
Incorporation by reference, Intergovernmental relations, Lead, Nitrogen 
dioxide, Ozone, Particulate matter, Reporting and recordkeeping 
requirements, Sulfur oxides, Volatile organic compounds.

    Dated: February 28, 2023.
Meghan A. McCollister,
Regional Administrator, Region 7.

    For the reasons stated in the preamble, the EPA amends 40 CFR part 
52 as set forth below:

PART 52--APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS

0
1. The authority citation for part 52 continues to read as follows:

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

Subpart AA--Missouri

0
2. In Sec.  52.1320, the table in paragraph (c) is amended by revising 
the entry ``10-6.220'' to read as follows:


Sec.  52.1320  Identification of plan.

* * * * *
    (c) * * *

[[Page 14276]]



                                        EPA-Approved Missouri Regulations
----------------------------------------------------------------------------------------------------------------
                                                         State
     Missouri citation               Title          effective date    EPA approval date         Explanation
----------------------------------------------------------------------------------------------------------------
                                    Missouri Department of Natural Resources
----------------------------------------------------------------------------------------------------------------
 
                                                  * * * * * * *
----------------------------------------------------------------------------------------------------------------
    Chapter 6--Air Quality Standards, Definitions, Sampling and Reference Methods, and Air Pollution Control
                                      Regulations for the State of Missouri
----------------------------------------------------------------------------------------------------------------
 
                                                  * * * * * * *
10-6.220...................  Restriction of              3/30/2019  3/8/2023, [insert      Subsection (1)(I)
                              Emission of Visible                    Federal Register       referring to the
                              Air Contaminants.                      citation].             open burning rule,
                                                                                            10 CSR 10-6.045, is
                                                                                            not SIP approved.
 
                                                  * * * * * * *
----------------------------------------------------------------------------------------------------------------

* * * * *
[FR Doc. 2023-04507 Filed 3-7-23; 8:45 am]
BILLING CODE 6560-50-P