Document ID: EPA-R07-OAR-2022-0722-0001
Agency: epa
Document Type: Proposed Rule
Title: Air Quality State Implementation Plans; Approvals and Promulgations: Missouri; Ameren Sioux Sulfur Dioxide Consent Agreement
Posted Date: 2022-09-01T04:00Z

[Federal Register Volume 87, Number 169 (Thursday, September 1, 2022)]
[Proposed Rules]
[Pages 53703-53705]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2022-18724]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R07-OAR-2022-0722; FRL-10156-01-R7]

Air Plan Approval; Missouri; Ameren Sioux Sulfur Dioxide Consent 
Agreement

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: The Environmental Protection Agency (EPA) is proposing 
approval of source-specific revisions to the Missouri State 
Implementation Plan (SIP) received on April 21, 2022. In the 
submission, Missouri requests that the EPA incorporate into the SIP an 
additional sulfur dioxide (SO2) emissions limit for the 
Ameren Missouri (Ameren)--Sioux Energy Center (Sioux). Specifically, 
the EPA is proposing to approve, into the SIP, an additional 
SO2 emissions limit and associated operating restrictions, 
monitoring, recordkeeping, reporting (MRR) and testing compliance 
requirements established in a consent agreement as permanent and 
enforceable SO2 control measures.

DATES: Comments must be received on or before October 3, 2022.

ADDRESSES: You may send comments, identified by Docket ID No. EPA-R07-
OAR-2022-0722 to www.regulations.gov. Follow the online instructions 
for submitting comments.
    Instructions: All submissions received must include the Docket ID 
No. for this rulemaking. Comments received will be posted without 
change to www.regulations.gov/, including any personal information 
provided. For detailed instructions on sending comments and additional 
information on the rulemaking process, see the ``Written Comments'' 
heading of the SUPPLEMENTARY INFORMATION section of this document.

FOR FURTHER INFORMATION CONTACT: Jason Heitman, Environmental 
Protection Agency, Region 7 Office, Air Quality Planning Branch, 11201 
Renner Boulevard, Lenexa, Kansas 66219; telephone number: (913) 551-
7664; email address: [email protected].

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

Table of Contents

I. Written Comments
II. What is the background for this proposed action?
III. Have the requirements for approval of a SIP revision been met?
IV. What did Missouri submit in the source-specific SIP revision for 
Ameren Sioux?
V. What is the EPA's analysis of Missouri's source-specific SIP 
revision?
VI. What action is the EPA proposing?
VII. Environmental Justice Concerns
VIII. Incorporation by Reference
IX. Statutory and Executive Order Reviews

I. Written Comments

    Submit your comments, identified by Docket ID No. EPA-R07-OAR-2022-
0722, at www.regulations.gov. Once submitted, comments cannot be edited 
or removed from Regulations.gov. The EPA may publish any comment 
received to its public docket. Do not submit electronically any 
information you consider to be Confidential Business Information (CBI) 
or other information whose disclosure is restricted by statute. 
Multimedia submissions (audio, video, etc.) must be accompanied by a 
written comment. The written comment is considered the official comment 
and should include discussion of all points you wish to make. The EPA 
will generally not consider comments or comment contents located 
outside of the primary submission (i.e., on the web, cloud, or other 
file sharing system). For additional submission methods, the full EPA 
public comment policy, information about CBI or multimedia submissions, 
and general guidance on making effective comments, please visit 
www.epa.gov/dockets/commenting-epa-dockets.

II. What is the background for this proposed action?

    The Ameren Sioux facility is located in St. Charles County, 
Missouri, along the Mississippi River, just north of the City of St. 
Louis. The EPA designated the area surrounding Ameren Sioux as 
attainment/unclassifiable for the 2010 1-hour SO2 NAAQS in 
early 2018 (83 FR 1098, January 9, 2018). Unlike with a nonattainment 
designation, a designation of attainment/unclassifiable does not impose 
any new SO2 planning requirements on the Missouri Department 
of Natural Resources (MoDNR) for Ameren Sioux in Missouri's SIP.
    Ameren Sioux operates two coal-fired boilers that generate 
electricity for use in the region. In 2010, Ameren Sioux installed wet 
flue-gas desulfurization control technology at their two boilers. The 
existing enforceable SO2 emissions limit in the Missouri SIP 
for Sioux is much higher than recent actual emissions and therefore 
does not reflect operation of the control technology. This control 
technology reduced the actual SO2 emissions at Ameren Sioux 
by nearly 90 percent.
    Ameren Sioux is required to operate a continuous emission 
monitoring system (CEMS) for SO2 on both of their 
boilers.\1\ This allows for the reporting of actual hourly emissions 
levels coming from the two boilers at the facility. The Consent 
Agreement included in this proposed SIP revision also requires the use 
of their CEMS to demonstrate compliance with the additional enforceable 
limit in the Consent Agreement.
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    \1\ See 40 CFR part 75.
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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 this SIP revision from December 27, 
2021 to February 3, 2022 and received one comment. In addition, the 
revision meets the substantive SIP requirements of the CAA, including 
section 110 and implementing regulations.

IV. What did Missouri submit in the source-specific SIP revision for 
Ameren Sioux?

    The SO2 emissions limit and averaging time included in 
the Consent

[[Page 53704]]

Agreement for Ameren Sioux are provided in Table 1. The limit is listed 
as a facility-wide limit, but only applies to Boilers 1 and 2 at the 
facility.

                         Table 1--Ameren Missouri Sioux Energy Center SO2 Emission Limit
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                                                                Emission limit
                                                                  per source
                    Source                        Source ID     (pounds SO2 per           Averaging time
                                                                     hour)
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Ameren Missouri--Sioux Energy Center.........         1830001             7,342  24-hour block average.
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    Ameren will maintain all hourly data and computations related to 
demonstrating compliance with the 24-hour block average emissions limit 
and keep this data for a period of at least five years. Ameren shall 
report on compliance with the emissions limit in Table 1 on the same 
schedule as the annual compliance certification required in accordance 
with the operating permits issued under 40 CFR part 70.

V. What is the EPA's analysis of Missouri's source-specific SIP 
revision?

    The EPA is proposing to determine that the limit in the Consent 
Agreement is practically enforceable through the following analysis. 
The Consent Agreement requires Ameren to determine compliance with the 
emissions restrictions by use of the SO2 CEMS installed on 
Boilers 1 and 2 at Sioux. The CEMS will be operated in accordance with 
40 CFR part 75. The limit in the Consent Agreement is based on 24-hour 
block averages. The total pounds of SO2 emitted during each 
calendar day, as measured by the CEMS, is first summed for the subject 
units, then divided by the number of actual operating hours in that 
day. If this is less than or equal to the limit in Table 1, the 
facility is in compliance with the emissions limit. Only hours that 
meet the primary equipment hourly operating requirements of 40 CFR 
75.10(d) are used in calculating the daily 24-hour block average. For 
example, if the source only meets 40 CFR 75.10(d) operational 
requirements for one hour in a particular 24-hour block period, the 
compliance with the emissions limit would be calculated by the total 
emissions divided by the one hour of operation that meets 40 CFR 
75.10(d). Therefore, any day with at least one hour that meets 
operational requirements will have a calculated block average that will 
be used to demonstrate compliance with the emissions limit.
    While the Consent Agreement may be terminated under state law by 
mutual agreement by both parties at the current time, this action, once 
finalized, would approve that Agreement into the SIP. At that point the 
requirements of the Consent Agreement would be permanent and federally 
enforceable and would remain applicable until Missouri submits a SIP 
revision and the EPA approves that revision. That revision would be 
subject to CAA section 110(l), i.e., the state must demonstrate that 
the revision would not interfere with the attainment or maintenance of 
any NAAQS.

VI. What action is the EPA proposing?

    The EPA is proposing to approve Missouri's April 21, 2022, source-
specific SIP revision into the Missouri SIP. This revision includes a 
specific SO2 emissions limit and associated operating 
restrictions, MRR, and testing compliance requirements for the Ameren 
Sioux Facility as contained in Consent Agreement number APCP-2021-018. 
A copy of the Consent Agreement is included in the docket for this 
rulemaking.
    The purpose of the Consent Agreement is to provide for the new 
SO2 emissions limit at Ameren Sioux to be credited as an 
additional permanent and federally enforceable measure in Missouri's 
SIP. Ameren has voluntarily agreed to enter into this Consent Agreement 
to strengthen Missouri's SIP.
    The Consent Agreement includes a facility-wide 24-hour block 
average emissions limit. The additional SO2 emissions limit 
that the EPA proposes to approve is in addition to the SO2 
requirements currently in the SIP for Ameren Sioux. Incorporating an 
additional specific SO2 limit and associated operating 
restrictions, MRR, and testing compliance parameters for Ameren Sioux 
into the Missouri SIP would establish this additional specific 
SO2 limit and associated operating and compliance parameters 
as permanent and federally enforceable control measures and strengthen 
the Missouri SIP.
    The purpose of this rulemaking is to act on Missouri's request to 
approve into the SIP an additional specific facility-wide 
SO2 limit (listed in Table 1), and associated operating, 
MRR, and testing requirements established in a Consent Agreement, 
thereby making this limit permanent and federally enforceable to 
strengthen the Missouri SIP.

VII. Environmental Justice Concerns

    When the EPA establishes a new or revised NAAQS, the CAA requires 
the EPA to designate all areas of the U.S. as either nonattainment, 
attainment, or unclassifiable. Area designations address environmental 
justice concerns by ensuring that the public is properly informed about 
the air quality in an area. In this action, the EPA is proposing to 
approve an additional emissions limit for a source into the Missouri 
SIP.
    The EPA utilized the EJSCREEN tool to evaluate environmental and 
demographic indicators within the area. The tool outputs report is 
contained in the docket for this action. While the EPA's EJSCREEN tool 
demonstrates that demographic indicators are consistent or lower than 
national averages, there are vulnerable populations in the area 
including low-income populations and persons over 64 years of age.
    Based on the information presented in this document, this proposed 
action does not result in disproportionately high and adverse human 
health or environmental effects on minority populations, low-income 
populations and/or indigenous peoples.

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 the Missouri Consent Agreement discussed in 
section VI of this preamble and as set forth below in the proposed 
revision to 40 CFR part 52. 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).

[[Page 53705]]

IX. 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 VII of this action, 
``Environmental Justice Concerns.''
    The SIP is not approved to apply on any Indian reservation land or 
in any other area where the EPA or an Indian tribe has demonstrated 
that a tribe has jurisdiction. In those areas of Indian country, the 
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, Incorporation by 
reference, Intergovernmental relations, Reporting and recordkeeping 
requirements, Sulfur oxides.

    Dated: August 24, 2022.
Meghan A. McCollister,
Regional Administrator, Region 7.

    For the reasons stated in the preamble, the EPA proposes to amend 
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 (d) is amended by adding 
the entry ``(37)'' in numerical order to read as follows:

Sec.  52.1320   Identification of plan.

* * * * *
    (d) * * *

                            EPA-Approved Missouri Source-Specific Permits and Orders
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                                                            State
          Name of source             Order/permit No.     effective     EPA approval date        Explanation
                                                             date
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                                                  * * * * * * *
(37) Ameren Missouri--Sioux        Consent Agreement       3/31/2022  [Date of publication
 Energy Center.                     No. APCP-2021-018.                 of the final rule
                                                                       in the Federal
                                                                       Register], [Federal
                                                                       Register citation
                                                                       of the final rule].
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[FR Doc. 2022-18724 Filed 8-31-22; 8:45 am]
BILLING CODE 6560-50-P