[Federal Register Volume 85, Number 70 (Friday, April 10, 2020)]
[Proposed Rules]
[Pages 20342-20378]
[FR Doc No: 2020-07471]

Vol. 85

Friday,

No. 70

April 10, 2020

Part II

Environmental Protection Agency

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40 CFR Part 63

Mercury and Air Toxics Standards for Power Plants Electronic Reporting
Revisions; Proposed Rule

Federal Register / Vol. 85, No. 70 / Friday, April 10, 2020 /
Proposed Rules

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 63

[EPA-HQ-OAR-2018-0794; FRL-10007-27-OAR]
RIN 2060-AU70

Mercury and Air Toxics Standards for Power Plants Electronic
Reporting Revisions

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: The U.S Environmental Protection Agency (EPA) is proposing
amendments to the electronic reporting requirements for the National
Emission Standards for Hazardous Air Pollutants: Coal- and Oil-Fired
Electric Utility Steam Generating Units (also known as the Mercury and
Air Toxics Standards (MATS)). This proposed action would revise and
streamline the electronic data reporting requirements of MATS and
increase data transparency by requiring use of one electronic reporting
system, instead of two separate systems, and provide enhanced access to
MATS data. No new continuous monitoring requirements would be imposed
by this proposed action; instead, this action would reduce reporting
burden, increase MATS data flow and usage, make it easier for
inspectors and auditors to assess compliance, and encourage wider use
of continuous emissions monitoring systems (CEMS) for MATS compliance.
In addition, this proposed action would extend the current deadline for
alternative electronic data submission via portable document format
(PDF) files through December 31, 2023.

DATES:
    Comments. Comments must be received on or before May 11, 2020.
    Public hearing. If anyone contacts us requesting a public hearing
on or before April 15, 2020, we will hold a hearing. Additional
information about the hearing, if requested, will be posted at https://www.epa.gov/mats/regulatory-actions-final-mercury-and-air-toxics-standards-mats-power-plants. See SUPPLEMENTARY INFORMATION for
information on requesting and registering for a public hearing.

ADDRESSES: You may send comments, identified by Docket ID No. EPA-HQ-
OAR-2018-0794, by any of the following methods:
     Federal eRulemaking Portal: https://www.regulations.gov/
(our preferred method). Follow the online instructions for submitting
comments.
     Email<EMAIL_ADDRESS>Include Docket ID No. EPA-
HQ-OAR-2018-0794 in the subject line of the message.
    Instructions: All submissions received must include the Docket ID
No. for this rulemaking. Comments received may be posted without change
to https://www.regulations.gov/, including any personal information
provided. For detailed instructions on sending comments and additional
information on the rulemaking process, see the SUPPLEMENTARY
INFORMATION section of this document.
    Out of an abundance of caution for members of the public and our
staff, the EPA Docket Center and Reading Room will be closed to public
visitors beginning at the close of business on March 31, 2020 (4:30
p.m.) to reduce the risk of transmitting COVID-19. Our Docket Center
staff will continue to provide remote customer service via email,
phone, and webform. We encourage the public to submit comments via
https://www.regulations.gov/ or email, as there will be a delay in
process mail and no hand deliveries will be accepted. For further
information on EPA Docket Center services, please visit us online at
https://www.epa.gov/dockets.

FOR FURTHER INFORMATION CONTACT: Mr. Barrett Parker, Sector Policies
and Programs Division (D243-05), Office of Air Quality Planning and
Standards, U.S. Environmental Protection Agency, Research Triangle
Park, NC 27711; telephone number:<PHONE_NUMBER>; email address:
<EMAIL_ADDRESS>For general information concerning MATS,
contact Ms. Mary Johnson, Sector Policies and Programs Division (D243-
01), Office of Air Quality Planning and Standards, U.S. Environmental
Protection Agency, Research Triangle Park, NC 27711; telephone number:
(919) 541-5025. For questions concerning the Emissions Collection and
Monitoring Plan System (ECMPS) Client Tool and its implementation,
contact Mr. Christopher Worley, Clean Air Markets Division, Mail Code
6204M, U.S. Environmental Protection Agency, 1200 Pennsylvania Ave. NW,
Washington, DC 20460; telephone number:<PHONE_NUMBER>; email address:
<EMAIL_ADDRESS>
SUPPLEMENTARY INFORMATION: The information in this preamble is
organized as follows:

Table of Contents

I. Public Participation
II. General Information
    A. Does this action apply to me?
    B. What action is the Agency taking?
    C. What is the Agency's authority for taking this action?
    D. What are the incremental costs and benefits of this action?
III. Background
IV. What is the scope of these proposed amendments?
V. What specific amendments to 40 CFR part 63, subpart UUUUU, are
proposed by this action?
    A. Proposed Revisions to the Reporting Requirements of MATS
    B. Revisions to Appendix A
    C. Revisions to Appendix B
    D. Addition to Appendix C
    E. Addition to Appendix D
    F. Addition to Appendix E
VI. Proposed Revisions to Other Rule Text
VII. Statutory and Executive Order Reviews
    A. Executive Order 12866: Regulatory Planning and Review and
Executive Order 13563: Improving Regulation and Regulatory Review
    B. Executive Order 13771: Reducing Regulations and Controlling
Regulatory Costs
    C. Paperwork Reduction Act (PRA)
    D. Regulatory Flexibility Act (RFA)
    E. Unfunded Mandates Reform Act (UMRA)
    F. Executive Order 13132: Federalism
    G. Executive Order 13175: Consultation and Coordination With
Indian Tribal Governments
    H. Executive Order 13045: Protection of Children From
Environmental Health Risks and Safety Risks
    I. Executive Order 13211: Actions Concerning Regulations That
Significantly Affect Energy Supply, Distribution, or Use
    J. National Technology Transfer and Advancement Act (NTTAA)
    K. Executive Order 12898: Federal Actions To Address
Environmental Justice in Minority Populations and Low-Income
Populations

I. Public Participation

    Public hearing. Please contact Ms. Adrian Gates at<PHONE_NUMBER>
or by email at<EMAIL_ADDRESS>to request a public hearing, to
register to speak at the public hearing, or to inquire as to whether a
public hearing will be held.
    Docket. The EPA has established a docket for this rulemaking under
Docket ID No. EPA-HQ-OAR-2018-0794. All documents in the docket are
listed in Regulations.gov. Although listed, some information is not
publicly available, e.g., Confidential Business Information (CBI) or
other information whose disclosure is restricted by statute. Certain
other material, such as copyrighted material, is not placed on the
internet. Publicly available docket materials are available
electronically in Regulations.gov.
    The EPA is temporarily suspending its Docket Center and Reading
Room for public visitors to reduce the risk of transmitting COVID-19.
Written

comments submitted by mail will be delayed and no hand deliveries will
be accepted. Our Docket Center staff will continue to provide remote
customer service via email, phone, and webform. We encourage the public
to submit comments via https://www.regulations.gov/. For further
information and updates on EPA Docket Center services, please visit us
online at https://www.epa.gov/dockets.
    The EPA continues to carefully and continuously monitor information
from the Centers for Disease Control and Prevention, local area health
departments, and our Federal partners so we can respond rapidly as
conditions change regarding COVID-19.
    Instructions. Direct your comments to Docket ID No. EPA-HQ-OAR-
2018-0794. The EPA's policy is that all comments received will be
included in the public docket without change and may be made available
online at https://www.regulations.gov/, including any personal
information provided, unless the comment includes information claimed
to be CBI or other information whose disclosure is restricted by
statute. Do not submit information that you consider to be CBI or
otherwise protected through https://www.regulations.gov/ or email. This
type of information should be submitted by mail as discussed below.
    The EPA may publish any comment received to its public docket.
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 https://www.epa.gov/dockets/commenting-epa-dockets.
    The https://www.regulations.gov/ website allows you to submit your
comment anonymously, which means the EPA will not know your identity or
contact information unless you provide it in the body of your comment.
If you send an email comment directly to the EPA without going through
https://www.regulations.gov/, your email address will be automatically
captured and included as part of the comment that is placed in the
public docket and made available on the internet. If you submit an
electronic comment, the EPA recommends that you include your name and
other contact information in the body of your comment and with any
digital storage media you submit. If the EPA cannot read your comment
due to technical difficulties and cannot contact you for clarification,
the EPA may not be able to consider your comment. Electronic files
should not include special characters or any form of encryption and be
free of any defects or viruses. For additional information about the
EPA's public docket, visit the EPA Docket Center homepage at https://www.epa.gov/dockets.
    Submitting CBI. Do not submit information containing CBI to the EPA
through https://www.regulations.gov/ or email. Clearly mark the part or
all of the information that you claim to be CBI. For CBI information on
any digital storage media that you mail to the EPA, mark the outside of
the digital storage media as CBI and then identify electronically
within the digital storage media the specific information that is
claimed as CBI. In addition to one complete version of the comments
that includes information claimed as CBI, you must submit a copy of the
comments that does not contain the information claimed as CBI directly
to the public docket through the procedures outlined in Instructions
above. If you submit any digital storage media that does not contain
CBI, mark the outside of the digital storage media clearly that it does
not contain CBI. Information not marked as CBI will be included in the
public docket and the EPA's electronic public docket without prior
notice. Information marked as CBI will not be disclosed except in
accordance with procedures set forth in 40 Code of Federal Regulations
(CFR) part 2. Send or deliver information identified as CBI only to the
following address: OAQPS Document Control Officer (C404-02), OAQPS,
U.S. Environmental Protection Agency, Research Triangle Park, North
Carolina 27711, Attention Docket ID No. EPA-HQ-OAR-2018-0794. Note that
written comments containing CBI and submitted by mail will be delayed
and no hand deliveries will be accepted.

II. General Information

A. Does this action apply to me?

    Categories and entities potentially affected by this proposed
action include:

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                                                         Examples of
             Category                NAICS code 1        potentially
                                                     regulated entities
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Industry..........................          221112  Fossil fuel-fired
                                                     electric utility
                                                     steam generating
                                                     units (EGUs).
Federal government................        2 221122  Fossil fuel-fired
                                                     EGUs owned by the
                                                     Federal government.
State/local/tribal government.....        2 221122  Fossil fuel-fired
                                                     EGUs owned by
                                                     municipalities.
                                            921150  Fossil fuel-fired
                                                     EGUs in Indian
                                                     country.
------------------------------------------------------------------------
\1\ North American Industry Classification System.
\2\ Federal, state, or local government-owned and operated
  establishments are classified according to the activity in which they
  are engaged.

    This table is not intended to be exhaustive, but rather provides a
guide for readers regarding entities likely to be regulated by this
action. This table lists the types of entities that EPA is now aware
could potentially be regulated by this action. Other types of entities
not listed in the table could also be regulated. To determine whether
your entity is regulated by this proposed action, you should carefully
examine the applicability criteria in 40 CFR 63.9981 of the rule. If
you have questions regarding the applicability of this action to a
particular entity, consult either the air permitting authority for the
entity or your EPA Regional representative as listed in 40 CFR 63.13.

B. What action is the Agency taking?

    The EPA proposes this rule to streamline the electronic data
reporting requirements of MATS; to increase data transparency by making
more of the MATS data available in Extensible Markup Language (XML)
format; and to amend the reporting and recordkeeping requirements
associated with performance stack tests, particulate matter (PM) and
hydrogen chloride (HCl) CEMS, and PM continuous parameter monitoring
systems (CPMS).

C. What is the Agency's authority for taking this action?

    The Agency's authority for taking this action is found at 42 U.S.C.
7401 et seq.

D. What are the incremental costs and benefits of this action?

    As discussed in section VII.C of this preamble, this action is
expected to

reduce overall annual source burden by 11,000 hours per year, which
when monetized is $15,079,000.

III. Background

    These proposed amendments would revise the recordkeeping and
reporting requirements of the MATS rule, in response to concerns raised
by the regulated community. The MATS rule originally required affected
EGU owners or operators to report MATS rule emissions and compliance
information electronically using two data systems. See 40 CFR 63.10031
(77 FR 9304, February 16, 2012). Paragraph (a) of 40 CFR 63.10031
required EGU owners or operators that demonstrate compliance by
continuously monitoring mercury (Hg) and/or HCl and/or hydrogen
fluoride (HF) emissions to use the Emissions Collection and Monitoring
Plan System (ECMPS) Client Tool to submit monitoring plan information,
quality assurance test results, and hourly emissions data in accordance
with appendices A and B to subpart UUUUU of 40 CFR part 63. Paragraph
(f) of 40 CFR 63.10031 required performance stack test results,
performance evaluations of Hg, HCl, HF, sulfur dioxide
(SO2), and PM CEMS, 30-boiler operating day rolling average
values for certain parameters, Notifications of Compliance Status, and
semiannual compliance reports to be submitted to the EPA's WebFIRE
database via the Compliance and Emissions Data Reporting Interface
(CEDRI).
    Subsequent to the publication of the MATS rule, stakeholders
suggested to the EPA that the MATS rule electronic reporting burden
could be significantly reduced if all of the required information were
reported to one data system instead of two. The stakeholders also
suggested that using one data system would benefit the EPA and the
public in their review of MATS rule data, because the information would
be reported in a consistent format. In view of these considerations,
the stakeholders urged the EPA to consider amending the MATS rule to
require all of the data to be reported through the ECMPS, a familiar
data system that most EGU owners or operators have been using since
2009 to meet the electronic reporting requirements of the Acid Rain
Program.
    After careful consideration of the stakeholders' recommendations,
the EPA concluded that the increased transparency of the emissions data
and the reduction in reporting burden that could be achieved through
the use of a single data system are consistent with Agency priorities.
As a result, late in 2014 the EPA decided to take the necessary steps
to require all of the electronic reports required by the MATS rule to
be submitted through the ECMPS Client Tool. Those steps would include
revising the MATS rule, modifying the ECMPS Client Tool, creating a
detailed set of reporting instructions, and beta testing the modified
software. Recognizing that insufficient time was available to complete
these tasks before the initial compliance date for the MATS rule (April
16, 2015), the Agency embarked on a two-phased approach to complete
them.
    The first phase was completed when the EPA published a final rule
requiring EGU owners or operators to suspend temporarily (until April
16, 2017) the use of the CEDRI interface as the means of submitting the
reports described in 40 CFR 63.10031(f) introductory text and (f)(1),
(2), and (4), and to use the ECMPS Client Tool to submit PDF versions
of these reports on an interim basis (see 80 FR 15510, March 24, 2015).
The specific reports required to be submitted as PDF files included:
Performance stack test reports containing enough information to assess
compliance and to demonstrate that the testing was done properly;
relative accuracy test audit (RATA) reports for SO2, HCl,
HF, and Hg CEMS; RATA reports for Hg sorbent trap monitoring systems;
response correlation audit (RCA) and relative response audit (RRA)
reports for PM CEMS; 30-boiler operating day rolling average reports
for PM CEMS, PM CPMS, and approved hazardous air pollutants (HAP)
metals CEMS; Notifications of Compliance Status; and semiannual
compliance reports. Title 40 CFR 63.10031(f)(6) of the March 24, 2015,
final rule required each PDF version of a submitted interim report to
include information that identifies the facility (name and address),
the EGU(s) to which the report applies, the applicable rule citations,
and other information. The rule further specified that in the event
that implementation of the single data system initiative was not
completed by April 16, 2017, the electronic reporting of MATS data
would revert to the original two systems approach on and after that
date.
    In the preamble to the March 24, 2015, final rule, the EPA outlined
the second phase of the single data system initiative, to be executed
during the interim PDF reporting period. In phase two: (1) The Agency
would publish a direct final rule, requiring MATS-affected sources to
use the ECMPS Client Tool to submit all required reports; and (2) a
detailed set of reporting instructions would be developed and ECMPS
would be modified to receive and process the data.
    Considering the magnitude of the rule changes that would be
required to execute phase two, coupled with the need to specify data
elements to be reported electronically for PM CEMS, PM CPMS, and HCl
CEMS, the Agency decided to provide stakeholders an opportunity to
review and comment on the proposed changes. The EPA issued the proposed
rule on September 29, 2016.\1\ The comment period for the 2016 proposal
(or previous proposal) was scheduled to close on October 31, 2016, but
it was subsequently extended until November 15, 2016, in response to
requests from several stakeholders for an extension.
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    \1\ 81 FR 67062, September 29, 2016.
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    Commenters were generally supportive of the initiative to simplify
and streamline the MATS reporting requirements and to use the ECMPS
Client Tool as the single MATS rule reporting system. However, they
expressed serious concerns about the proposal to extend the interim PDF
reporting process from April 16, 2017, to December 31, 2017. Although
they favored an extension of the PDF reporting, they were unanimous in
asserting that the proposed end date of December 31, 2017, would not
allow enough time to finalize the rule, develop the necessary XML
reporting formats and reporting instructions, and reprogram the ECMPS
Client Tool. In addition, two data acquisition and handling system
vendors stated that more time would be needed for them to adapt to the
proposed changes and to develop the reporting software for their
customers. Some of the commenters recommended that the EPA should
extend the interim PDF reporting process through calendar year 2019;
others suggested that the process should be extended for 6 to 8
calendar quarters after finalization of the rule.
    In view of these considerations, on April 6, 2017, the EPA
published a final rule extending the interim PDF file reporting process
through June 30, 2018 (82 FR 16736). Technical corrections to appendix
A were also included in the rule package. The rule went into effect on
April 6, 2017. As the Agency was unable to compete the e-reporting
provisions, another extension to the interim PDF file reporting
process--through June 30, 2020--was promulgated on July 2, 2018 (83 FR
30879). This action proposes to further extend the interim PDF
reporting process through December 31, 2023, and proposes the remaining
needed amendments to the MATS rule on

electronic reporting. Note that these proposed amendments were
developed after consideration of the comments received on the September
29, 2016, proposal.

IV. What is the scope of these proposed amendments?

    This proposed action would amend the reporting requirements in 40
CFR 63.10031 of the MATS regulation, and, for consistency with those
changes, would amend related text in 40 CFR part 63, subpart UUUUU;
specifically, 40 CFR 63.10000, 63.10005, 63.10009, 63.10010, 63.10011,
63.10020, 63.10021, 63.10030, 63.10032, 63.10042, and Tables 3, 8, and
9. The recordkeeping and reporting sections of appendices A and B are
also proposed to be amended \2\ and three new appendices are proposed
to be added to the rule, i.e., appendices C, D, and E. Instead of using
the electronic reporting tool (ERT) to submit some of the MATS data via
CEDRI and submitting the remainder through the ECMPS Client Tool, as
was required by the original MATS rule, this proposed action would
allow EGU owners or operators to use the ECMPS Client Tool to report
all of the required information in XML and PDF files.
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    \2\ In 2015, the EPA published a technology-neutral performance
specification and associated quality assurance (QA) test procedures
for HCl monitors (see Performance Specification 18 (PS 18) and
Quality Assurance Procedure 6 (Procedure 6) in 80 FR 38628, July 7,
2015). That rule added certification and QA test requirements for
sources electing to monitor HCl according to PS 18 and Procedure 6.
This proposed action would require the results of the appendix B
certification and QA tests to be reported electronically for periods
beginning on January 1, 2024.
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V. What specific amendments to 40 CFR part 63, subpart UUUUU, are
proposed by this action?

    The proposed amendments to 40 CFR part 63, subpart UUUUU, are
discussed in detail in the paragraphs below.

A. Proposed Revisions to the Reporting Requirements of MATS

    The reporting requirements of MATS are proposed to be amended as
follows:
    (1) The ECMPS Client Tool would be used as the exclusive data
system for MATS reporting, in lieu of using both ECMPS and the CEDRI.
    (2) The interim PDF reporting process described in 40 CFR
63.10031(f) would be further extended through December 31, 2023, to
allow sufficient time for software development, programming, and
testing. Until then, compliance with the emissions and operating limits
would continue to be assessed based on the various PDF report
submittals described in 40 CFR 63.10031(f) and data from Hg, HCl, HF,
and SO2 CEMS and sorbent trap monitoring systems, as
reported through the ECMPS Client Tool. On and after January 1, 2024,
compliance with the emissions and operating limits would be assessed
based on: (1) Quarterly compliance reports; (2) hourly data from all
continuous monitoring systems (CMS) (including PM CEMS and PM CPMS) in
XML format; (3) detailed reference method information for stack tests
and CMS performance evaluations in XML format and PDF files; (4)
Notifications of Compliance Status (if any), in PDF files; and, (5) if
applicable, supplementary data in PDF files for EGUs using paragraph
(2) of the definition of ``startup'' in 40 CFR 63.10042. The ECMPS
Client Tool would be used to submit all of these reports and
notifications.
    (3) In order to properly close out the interim PDF reporting
process, 40 CFR 63.10031(f)(6) would state that PDF submittals will
still be accepted as necessary for the reports required under paragraph
(f) introductory text, (f)(1), (2), or (4) if the deadlines for
submitting those reports extend beyond December 31, 2023. As an
example, the last semiannual compliance report under the interim PDF
reporting process would cover the period from July 1, 2023, through
December 31, 2023; the deadline for submitting this report would be
January 30, 2024, and the report would be submitted using the interim
PDF reporting process.
    (4) Revised paragraph (f)(2) of 40 CFR 63.10031 would expand the
quarterly reporting of 30- or 90-boiler operating day rolling average
emission rates to include units monitoring Hg, HCl, HF, and/or
SO2 emissions, and units using emissions averaging. This
change is consistent with 40 CFR 63.10031(f)(2) of the current rule,
which requires quarterly reporting of 30-boiler operating day rolling
averages for EGUs using PM CEMS, PM CPMS, and approved HAP metals CEMS.
Therefore, starting with the first quarter of 2024, the 30- or 90-
boiler operating day rolling averages (or, if applicable, rolling
weighted average emission rates (WAERs) if emissions averaging is used)
would be reported quarterly in XML format for all parameters (including
Hg, HF, HCl, and SO2). However, instead of providing these
rolling averages in separate, stand-alone reports, they would be
incorporated into the quarterly compliance reports required under 40
CFR 63.10031(g) (see section IV.A.(9) of this preamble, below).
    (5) Revised paragraphs (a)(1), (2), and (5) of 40 CFR 63.10031
would clarify the electronic reporting requirements for the Hg, HCl,
HF, SO2, and auxiliary CMS. Specifically:
    (i) Paragraph (a)(1) would require the electronic reporting
requirements of appendix A to be met if Hg CEMS or sorbent trap
monitoring systems are used.
    (ii) Paragraph (a)(2) would require the electronic reporting
requirements of appendix B to be met, with one important qualification,
if HCl or HF monitoring systems are used. Until December 31, 2023, if
Performance Specification (PS) 18 in part 60, appendix B, is used to
certify an HCl monitor and Procedure 6 in part 60, appendix F, is used
for on-going quality assurance (QA) of the monitor, EGU owners or
operators would temporarily report only data that the existing
programming of ECMPS is able to accommodate, i.e., hourly HCl emissions
data and the results of daily calibration drift tests and RATAs;
records would have to be kept of all of the other required
certification and QA tests and supporting data. The reason for this
temporary, limited reporting is that PS 18 and Procedure 6 were not
published until July 7, 2015; therefore, it was not possible to specify
recordkeeping and reporting requirements for them in the original
version of appendix B. Now that PS 18 and Procedure 6 have been
finalized, this rule would add the necessary recordkeeping and
reporting requirements, and the interim reporting for HCl would be
discontinued as of January 1, 2024 (for further discussion, see section
IV.C of this preamble).
    (iii) Paragraph (a)(5) would clarify the electronic reporting
requirements for the SO2 CEMS and the auxiliary monitoring
systems under MATS. Sources currently reporting SO2 mass
emissions under the Acid Rain Program or Cross-State Air Pollution Rule
already meet these requirements, except for paragraphs (a)(5)(iii)(C)
and (E), which would require, respectively, quarterly reporting of an
hourly SO2 emission rate data stream in units of the
applicable MATS standard (i.e., pounds per British thermal units (lb/
MMBtu) or pounds per megawatt hours (lb/MWh)) and certification
statements from the responsible official. Separate certification
statements would be required for the 40 CFR part 75 programs and MATS.
(Note: For consistency with the changes described in items (i) through
(iii), immediately above, 40 CFR 63.10031(f)(3) would be removed and
reserved).
    (6) Paragraphs (b)(1) and (2) of 40 CFR 63.10031 would be amended
to recognize that some EGUs may have received extensions of their
compliance

date under 40 CFR 63.6(i)(4). References to postmark dates for
submittal of semiannual compliance reports paragraphs would be removed
from paragraphs (b)(2) and (4); these reports currently are, and would
continue to be, submitted electronically through ECMPS as PDF files,
until they are superseded by quarterly compliance reports, starting in
the first quarter of 2024.
    (7) The provision in 40 CFR 63.10031(b)(5), which allowed affected
EGU owners or operators to follow alternate submission schedules for
semiannual compliance reports would be removed. The uniform submission
schedule described in 40 CFR 63.10031(b)(1) through (4) would be
required for all affected EGUs, so that compliance with this reporting
requirement can easily be tracked.
    (8) Revised 40 CFR 63.10031(b)(5) would require EGU owners or
operators to discontinue submission of semiannual compliance reports
when the interim PDF reporting period ends. The final semi-annual
compliance report would cover the period from July 1, 2023, through
December 31, 2023.
    (9) EGU owners or operators would submit quarterly compliance
reports in lieu of the semiannual compliance reports, starting with
reports covering the first quarter of 2023 (see 40 CFR 63.10031(g)).
The quarterly compliance reports would retain many features of the
semiannual reports and consolidate them with other reports that were
originally required to be submitted separately on different schedules.
These compliance reports would be due within 60 days after the end of
each calendar quarter, which would allow sufficient time to receive the
results of stack tests (particularly PM, HCl, and HF tests) performed
at or near the end of a calendar quarter. Each quarterly compliance
report would include the applicable data elements listed in sections 2
through 13 of appendix E.
    The owner or operator's MATS compliance strategy determines which
of the data elements in sections 2-13 of appendix E would be included
in the quarterly compliance reports. If continuous emission monitoring
were used to demonstrate compliance on a 30- or 90-boiler operating day
rolling average basis, the quarterly compliance reports would include
all of the 30- or 90-day averages calculated during the quarter. If
emissions averaging were used, EGU owners or operators would report all
of the 30- or 90-group boiler operating day WAERs calculated during the
quarter. If periodic stack testing for compliance were performed
(including Hg Low-Emitting EGU (LEE) tests and PM tests to set
operating limits for PM CPMS), the EGU owner or operator would report a
summary of each test completed during the calendar quarter and indicate
whether the test has a special purpose (i.e., if it were to be used to
establish LEE status or for emissions averaging).
    The quarterly compliance reports would retain and incorporate the
following features of the semiannual compliance reports: (1) Boiler
tune-up dates; (2) monthly fuel usage data; (3) process and control
equipment malfunction information; (4) reporting of deviations; and (5)
emergency bypass information, for certain EGUs that qualify for and
elect to use the LEE compliance option for Hg. However, for EGU owners
or operators who elect to (or are required to) use CMS to demonstrate
compliance, these quarterly reports, to some extent, would move away
from traditional ``exception only'' reporting. Currently, reporting of
the excess emissions and monitor downtime information described in 40
CFR 63.10(e)(3)(v) and (vi) in PDF files has been required as part of
the semiannual compliance reports. That information includes, among
other things, identification of excess emissions periods,
identification of periods when the monitoring system was inoperative or
out of control, the reasons for the excess emission and monitor
downtime periods, corrective actions or preventative measures taken,
description of repairs or adjustments to inoperative or out-of-control
CMS, the total amount of source operating time in the reporting period,
and the excess emissions and monitor downtime, expressed as percentages
of the source operating time. As explained above, rather than this
traditional exception-only reporting, these proposed amendments would
require all of the 30- (or 90-) boiler operating day rolling averages
or WAERs for all parameters to be included in the quarterly compliance
reports. In addition, the following elements of the excess emissions
summary, with slight modifications, are proposed to be included in the
quarterly compliance reports: (1) The total number of source operating
hours in the quarter and (2) the total number of hours of monitoring
system downtime for various causes (known and unknown).
    As previously noted, the requirement to report deviations would be
retained in the quarterly compliance reports. Specifically, the
revisions to 40 CFR 63.10031(d) would require the applicable data
elements in section 13 of appendix E to be reported, which include the
nature of the deviation (section 13.2), a description of the deviation
(section 13.3), and any corrective actions taken (section 13.4).
Section 13.3 further specifies the minimum amount of information that
would be reported in the description of certain deviations (i.e.,
unmonitored bypass stack usage, emissions or operating limit
exceedances, monitoring system outages, and missed or late performance
stack tests).
    We believe that consolidating information in quarterly compliance
reports, as described above, rather than requiring separate submittals
of 30- (or 90-) boiler operating day rolling average reports, excess
emissions reports, and semiannual compliance reports that come in
separately at different times during the year, greatly simplifies
reporting and will make it easier for inspectors and auditors to assess
compliance with the standards. Also, quarterly, as opposed to
semiannual, reporting is advantageous because it shortens significantly
the interval between the time that deviation or exceedance reporting on
a term longer than quarterly occurs. Draft reporting instructions for
the quarterly compliance reports are provided in the rule docket and on
the OAQPS and Clean Air Markets Division (CAMD) websites. In response
to comments received, these instructions have been modified from a
previous draft version.
    (10) A new paragraph, (c)(10), is being proposed to be added to
Sec.  63.10031 and would require malfunction information to be included
in the semiannual compliance reports. This is not a new requirement; it
was previously found in paragraph (g). However, as explained above,
revised paragraph (g) would require quarterly compliance reports to be
submitted, starting in 2024. Therefore, to avoid losing the requirement
to report malfunction information in the semiannual compliance reports,
the former paragraph (g) would be renamed as paragraph (c)(10) and
would be added to the list of information that must be included in the
semiannual reports. The introductory text of paragraph (c) would also
be amended, to recognize the addition of paragraph (c)(10).
    (11) For consistency with the reporting requirements for the other
CMS, the Agency is not proposing a requirement for sources using PM
CPMS to submit separate quarterly excess emission summary reports in
addition to the quarterly compliance reports. After careful
consideration of comments on a previous proposal, we are persuaded that
sufficient information to assess compliance with the operating limits
of a PM CPMS would be provided

by: (1) The hourly PM CPMS response data reported in appendix D; (2)
the quarterly compliance reports, which specify the operating limit of
the PM CPMS, require deviations from the operating limit and monitoring
requirements to be reported, and include summarized results of the PM
tests used to develop the operating limits; and (3) the applicable
reference method data for the PM tests required to be reported under
sections 17-30 of appendix E.
    We are proposing to amend Table 9 to 40 CFR part 63, subpart UUUUU,
as follows to reflect the transition away from exception-only
reporting. The applicability of the recordkeeping and reporting
requirements for excess emission and monitor downtime summary reporting
in 40 CFR 63.10(c)(7), 63.7(c)(8), and 63.10(e)(3) would end on
December 31, 2023, with the phase-out of the semiannual compliance
reports.
    (12) One commenter on the previous proposal brought to light some
inconsistencies in the rule; regarding the way in which periods of
monitor downtime should be regarded and reported, i.e., whether or not
they are reportable deviations. The commenter pointed out that 40 CFR
63.10020(d) exempts monitoring equipment malfunctions and out-of-
control periods from being reported as deviations, whereas 40 CFR
63.10010(h)(6)(i), (i)(5)(i)(A) and (B), and (j)(4)(i)(A) and (B)
appear to say the opposite, requiring these downtime incidents to be
included in ``annual deviation reports.'' The EPA never intended to
exempt these particular monitor outages from being reported as
deviations; the Agency meant for the exemption to apply only to routine
QA and maintenance activities.\3\ Therefore, 40 CFR 63.10020(d) would
be clarified, and the statements in 40 CFR 63.10010(h)(6)(i),
(i)(5)(i)(A) and (B), and (j)(4)(i)(A) and (B) more closely represent
the Agency's position. But even there, the text is problematic, because
deviations are currently required to be reported in the semiannual
compliance reports (not in ``annual deviation reports'') and will
continue to be reported in the quarterly compliance reports when the
transition to quarterly reporting occurs. To address the
inconsistencies in 40 CFR 63.10020(d) and 63.10010(h)(6)(i),
(i)(5)(i)(A) and (B), and (j)(4)(i)(A) and (B), the proposed rule would
amend these rule sections by clarifying that monitor outages due to
monitoring equipment malfunctions and out-of-control periods are
deviations, and, therefore, would be reported as such in the compliance
reports.
---------------------------------------------------------------------------

    \3\ The following statement from the preamble of the original
MATS rule makes this clear: ``Hours when a monitoring system is out
of service would be counted as hours of monitor down-time and may be
a deviation from the monitoring requirements of this rule unless the
rule provides an exception for routine quality control and
maintenance activities.'' (77 FR 9375, February 16, 2012).
---------------------------------------------------------------------------

    The same commenter further asserted that there are other incorrect
statements in 40 CFR 63.10010(h)(6)(i), (i)(5)(i)(A), and (j)(4)(i)(A)
and (B), regarding the reporting of quality assurance/quality control
(QA/QC) activities for PM CPMS, PM CEMS, and HAP metals CEMS. These
rule sections all require the QA/QC activities to be reported ``per the
requirements of 40 CFR 63.10031(b).'' However, the reference to 40 CFR
63.10031(b), which provides the schedule for submitting semiannual
compliance reports, appears to be a typographical error. The commenter
recommended replacing it with a more general reference to 40 CFR
63.10031. The EPA agrees with the commenter that the reference to 40
CFR 63.10010(b) is inappropriate; but the comment led to examination of
inconsistencies between language in 40 CFR 63.10010(h)(6)(i),
(i)(5)(i)(A), and (j)(4)(i)(A) and (B) and language in 40 CFR
63.10010(h)(7), (i)(5)(ii), and (j)(4)(ii). The former sections require
QA/QC activities for PM CPMS, PM CEMS, and HAP metals CEMS to be
reported, while the latter sections state that the results of
monitoring system performance audits must only be made available ``upon
request.'' The Agency maintains reporting of QA test results is
mandatory for all CMS. In view of this, the EPA proposes the following
amendments. First, the reference to 40 CFR 63.10010(b) in the last
sentence in paragraphs (h)(6)(i) and (j)(4)(i)(A) and (B) would be
removed. Second, paragraphs (h)(7) and (j)(4)(ii) would be revised to
require the monitoring system performance evaluations of PM CPMS and
HAP metals CEMS to be reported. Third, a new paragraph, (k), would be
added to 40 CFR 63.10031, and would require the QA/QC activities for PM
CPMS and HAP metals CEMS to be reported quarterly in PDF files; these
reports would be due within 60 days after the end of each calendar
quarter, starting with a report for the first quarter of 2024 or, if
the methodology is not in use by the source owner or operator in the
first quarter of 2024, starting with the first calendar quarter in
which the PM CPMS or HAP metals CEMS methodology is used. Reporting as
PDF files is appropriate because there are no standardized QA test
procedures for these CMS in the CFR; their QA test requirements are
found only in source-specific MATS monitoring plans and will likely
vary from source-to-source. Finally, 40 CFR 63.10010(i) would be
revised in light of the addition of appendix C; paragraph (i) now
simply cross-references the appropriate sections of appendix C,
regarding the certification, operation, maintenance, on-going QA,
recordkeeping, and reporting requirements for PM CEMS.
    (13) In all cases in which periodic stack tests (including Hg LEE
tests and PM tests that are used to develop PM CPMS operating limits)
are performed to demonstrate compliance, the proposal would retain the
requirement for the EGU owner or operator to provide the applicable
reference method data in appendix E (i.e., sections 17 et seq.) for
each stack test that is performed to demonstrate compliance. Each of
these submittals would be required to accompany the quarterly
compliance report that covers the calendar quarter in which the test
was completed. For PM tests that are used to develop PM CPMS operating
limits, you would also be required to include the information in 40 CFR
63.10023(b)(2)(vi) as part of the Test Comment data element found in
section 17.25 of appendix E.
    (14) The applicable reference method data in sections 17 through 30
of appendix E would also be provided in XML format, starting with tests
completed on or after January 1, 2024, for each RATA of an Hg,
SO2, HCl, or HF monitoring system, and for each RRA, RCA, or
correlation test of a PM CEMS. The information in section 31 of
appendix E would also be provided in a PDF file for each test. The
appendix E information would be submitted concurrently with the
summarized electronic test results submitted to ECMPS under appendix A,
B, or C, or 40 CFR part 75 (for SO2 RATAs).
    (15) The ECMPS Client Tool would also be used to make the following
submittals in PDF files:
    (i) A detailed report of the current, active PS 11 correlation
test, if the EGU owner or operator is using a certified PM CEMS to
demonstrate compliance. For correlation tests completed prior to [DATE
60 DAYS AFTER DATE OF PUBLICATION OF THE FINAL RULE IN THE FEDERAL
REGISTER], the report would be due no later than 60 days after that
date. For correlation tests completed on or after [DATE 60 DAYS AFTER
DATE OF PUBLICATION OF THE FINAL RULE IN THE FEDERAL REGISTER], but
prior to January 1, 2024, the report would be due within 60 days after
the date on which the test is completed. (Note: For correlations
completed on and after January 1, 2024,

in lieu of a PDF report, the test results would be submitted
electronically according to section 7.2.4 of appendix C, together with
the applicable reference method data required under sections 17 through
31 of appendix E);
    (ii) Any initial Notification of Compliance Status issued on or
after January 1, 2024; and
    (iii) The information specified in 40 CFR 63.10031(c)(5)(ii) and
63.10020(e) for startup and shutdown incidents, if you are relying on
paragraph (2) of the definition of ``startup'' in 40 CFR 63.10042.
Starting with a report covering the first calendar quarter of 2024,
this information would be submitted along with the quarterly compliance
report. Note that 40 CFR 63.10031(c)(5)(iii) through (v), which require
the semiannual compliance reports to include the hourly CEMS and
operating parameter data recorded during startup and shutdown events
have not been carried over to this PDF report because this information
is duplicative of the hourly data reported electronically in the
quarterly emissions reports. Startup and shutdown hours are flagged in
the emissions reports and are identifiable for auditing purposes.
    (16) To accommodate the required PDF reports, the applicable data
elements in 40 CFR 63.10031(f)(6)(i) through (xii) would be proposed to
be entered into the ECMPS Client Tool at the time of submission of each
PDF file. Note that the amendment to data element (xii) would replace
the word ``conducted'' with the word ``completed.''
    (17) Although the ECMPS Client Tool would be used to submit the
required reports and notifications described in revised 40 CFR 63.10031
and Table 8, ECMPS would not evaluate any of the PDF submittals or any
of the XML-formatted reference method data from sections 17 through 31
of appendix E. Instead, these reports and notifications would be
transmitted directly through the EPA's Central Data Exchange using
CEDRI unaltered. ECMPS would, however, perform electronic checking of
the hourly PM CEMS data and the summarized RATAs, PM CEMS correlation
tests, RRAs, and RCAs that are submitted in XML format, in a manner
that is consistent with the way that certification and QA test results
are evaluated under the Acid Rain and Cross-State Air Pollution Rule
programs. ECMPS would use the results of these evaluations to assess
the quality-assured status of the Hg, HCl, HF, SO2, or PM
emissions data. In addition, ECMPS would perform basic checks of the
information in the quarterly compliance reports, e.g., checking for
completeness and proper formatting, but would leave compliance
assessment to those who review the reports. The EPA intends for all of
these various data submissions to work together in a complementary
fashion to enable meaningful compliance determinations. It is essential
that any problems with the data identified by the reviewers are
communicated to all involved and resolved appropriately. For example,
if, for a particular Hg RATA, a review of the reference method data
shows that the method was not done properly, the RATA would be
invalidated. If, at the time of this discovery, the deadline for
performing the RATA has passed and the allowable grace period has also
expired, this would result in invalidation of hourly emissions data,
from the expiration of the grace period until a valid RATA is performed
and passed. Consequently, resubmission of quarterly emissions reports,
recalculation of 30-day compliance averages, and resubmission of
quarterly compliance reports may become necessary.

B. Revisions to Appendix A

    We are proposing to amend four sections of appendix A, i.e.,
sections <IP_ADDRESS>, <IP_ADDRESS>, <IP_ADDRESS> and <IP_ADDRESS>, based on comments
received. The requirement in sections <IP_ADDRESS>, <IP_ADDRESS>, and <IP_ADDRESS> to
report Hg concentrations and emission rates to 3 significant figures
would be revised so that Hg concentrations in micrograms per standard
cubic meter ([mu]g/scm) and Hg emission rates in pounds per trillion
British Thermal Units or pounds per gigawatt-hour (lb/TBtu or lb/GWh)
would be reported with one leading non-zero digit and one decimal
place, in scientific notation. Conventional rounding would be used,
i.e., if the digit immediately following the first decimal place is 5
or greater, the digit in the first decimal place would be rounded
upward (increased by one); if the digit immediately following the first
decimal place is 4 or less, the digit in the first decimal place would
remain unchanged.
    The requirement in section <IP_ADDRESS> to submit monitoring plan
information at least 21 days before the applicable compliance date in
40 CFR 63.9984 would be revised. For new units or units that install Hg
monitoring systems in order to switch from another MATS-compliant
methodology to Hg monitoring, the monitoring plan information would be
submitted at least 21 days prior to the date on which certification
testing begins. However, for units implementing Hg monitoring with a
previously-certified Hg monitoring system, the monitoring plan could be
submitted prior to or concurrent with the first quarterly emissions
report--provided that the monitoring plan would be in place when the
first emissions report is submitted so that the ECMPS Client Tool would
be able to evaluate the data.

C. Revisions to Appendix B

    For affected source owners or operators desiring to continuously
monitor HCl emissions, the original version of appendix B required the
monitoring system to be certified according to PS 15 in appendix B to
40 CFR part 60. However, PS 15 applies only to Fourier Transform
Infrared (FTIR) Spectroscopy monitoring systems; therefore, the use of
other viable HCl monitoring technologies was excluded. In view of this,
the EPA regarded the requirement to use PS 15 exclusively as a
temporary measure, until a technology-neutral PS for HCl monitors could
be developed and published. In section 3.1 of appendix B, the Agency
stated its intention to publish such a PS in the near future together
with appropriate on-going QA requirements and to amend appendix B to
accommodate their use. This additional PS, (PS 18 in 40 CFR part 60,
appendix B), and the on-going QA test requirements (Procedure 6 in 40
CFR part 60, appendix F) were published on July 7, 2015 (80 FR 38628,
July 7, 2015).
    Now that technology-neutral certification and QA test requirements
for HCl monitors have been promulgated, EGU owners or operators may use
any viable HCl monitoring technology that can meet the PS. However, in
order for ECMPS to accommodate all of the tests required under PS 18
and Procedure 6, additional time must be allotted for software
development. In view of this, we are proposing to revise 40 CFR
63.10031(a)(2), as previously noted, to require only information that
is compatible with the existing programming of ECMPS to be reported
electronically through December 31, 2023; this includes hourly HCl
emissions data and the results of daily calibration drift tests and
RATAs. In the interim, EGU owners or operators would be required to
keep records of all of the other certification and QA tests, which
would be reported starting in 2024.
    We are proposing to revise the title to section 2.3 of appendix B
by deleting the reference to FTIR-only monitoring systems. In addition,
the recordkeeping and reporting sections of appendix B (i.e., sections
10 and 11) would be amended. Based on comments received, sections
<IP_ADDRESS> and <IP_ADDRESS>, HCl and

HF concentrations ([micro]g/scm) and emission rates (lb/MMBtu or lb/
MWh) would be reported with one leading non-zero digit and one decimal
place, in scientific notation, rather than reporting the concentrations
and rates to 3 significant figures. Conventional rounding would be
used, i.e., if the digit immediately following the first decimal place
is 5 or greater, the digit in the first decimal place would be rounded
upward (increased by one); if the digit immediately following the first
decimal place is 4 or less, the digit in the first decimal place would
remain unchanged. Sections 10 and 11 also specify the data elements
that would be recorded and reported for each of the tests required by
PS 18 and Procedure 6. The revisions would make a clear distinction
between the tests required for FTIR monitors that are following PS 15
and the test requirements of PS 18 and Procedure 6. Some of the tests
in PS 18 and Procedure 6 are similar to tests for which ECMPS
programming exists. For example, the ``measurement error test''
required for initial certification of the HCl monitor is structurally
the same as a 40 CFR part 75 linearity check. Other tests have no
counterpart in 40 CFR part 75 and would require special software
development and reporting instructions. Note that electronic reporting
of these tests through ECMPS would have been required if PS 18 and
Procedure 6 had been in place when the original MATS rule was
published. In view of this, for source owners or operators electing to
use HCl CEMS, the amendments to section 11 of appendix B would
introduce no unnecessary reporting burden. The results of certification
and on-going QA tests would be reported electronically for all CEMS
required under this rule in order for ECMPS to assess the quality-
assured status of the emissions data. The Agency also notes that not
all of the tests described in section 11 of appendix B would be
required for all HCl monitors. For example, some of the tests (i.e.,
beam intensity, temperature, and pressure verifications) are specific
to Integrated Path--Continuous Emission Monitoring Systems (IP-CEMS),
and Procedure 6 would offer a choice among three different types of
audits (i.e., cylinder gas audits, relative accuracy audits, or dynamic
spiking audits) for the required quarterly QA tests. In addition, based
on comments received, the reporting requirements for the interference
check (which is not necessarily performed on each individual analyzer)
would be reduced.
    For each RATA of HCl CEMS that are completed on and after January
1, 2024, the applicable reference method data in sections 17 through 31
of appendix E would be submitted along with the electronic summary of
results required under section 11 of appendix B. To the extent
practicable, these data would be submitted prior to or concurrent with
the relevant quarterly electronic emissions report. However, as
previously noted, this may not always be possible, particularly when
the RATA is done near the end of a calendar quarter. The EPA test
Methods 26 and 26A, unlike instrumental test methods, require
laboratory analyses of the collected samples and cannot provide test
results while the test team is on-site. In view of this, section 11.4
of appendix B would allow the test results to be submitted up to 60
days after the test completion date. ``Provisional'' status may be
claimed for the emissions data affected by the test, starting from the
date and hour in which the test was completed, and continuing until the
date and hour in which the test results are submitted. If the test is
successful, the status of the data in that time period would change
from provisional to quality-assured, and no further action is required.
However, if the test is unsuccessful, the provisional data would be
invalidated and resubmission of the affected emissions report(s) would
be required.
    Because a technology-neutral PS for HCl CEMS was not available
prior to April 16, 2015 (which was the compliance date for many of the
existing EGUs), EGU owners or operators interested in monitoring HCl
either had to use an FTIR system and follow PS 15 or implement another
compliance option (e.g., quarterly emission testing) while awaiting
publication of PS 18 and Procedure 6. In light of this, the EPA
proposes to revise and restructure section 11.5.1 of appendix B to
clarify when electronic reporting of hourly HCl emissions data begins.
There are two possibilities. In the first case, the monitor is used for
the initial compliance demonstration. This could either apply to a
certified FTIR monitor following PS 15 or to a certified monitor
following PS 18, if the owner or operator of the EGU received an
extension of the compliance date. In this case, EGU owners or operators
would begin reporting hourly HCl emissions through ECMPS with the first
operating hour of the initial compliance demonstration. In the second
case, another option, such as stack testing, is used for the initial
compliance demonstration and continuous monitoring is implemented at a
later time. In that case, EGU owners or operators would begin reporting
hourly HCl emissions reporting through ECMPS with the first operating
hour after successfully completing all required certification tests of
the CEMS. In either case, the first quarterly emissions report
submittal would be for the calendar quarter in which emissions
reporting begins.
    The requirement in section 11.3.1 to submit monitoring plan
information at least 21 days before the applicable compliance date in
40 CFR 63.9984 would be revised. For new units or units that install
HCl and/or HF monitoring systems in order to switch from another MATS-
compliant methodology to HCl and/or HF monitoring, the monitoring plan
information would be submitted at least 21 days prior to the date on
which certification testing begins. However, for units implementing HCl
and/or HF monitoring with a previously-certified monitoring system, the
monitoring plan could be submitted prior to or concurrent with the
first quarterly emissions report.

D. Addition of Appendix C

    A new appendix, i.e., appendix C, would been added to subpart UUUUU
of 40 CFR part 63. Appendix C sets forth the continuous monitoring and
reporting requirements for filterable PM. Appendix C is structurally
similar to appendices A and B, but there is one notable difference.
Appendix C would include provisions for installation and certification
of the PM CEMS, and for on-going QA of the data from the CEMS. The
monitoring system would be certified according to PS 11 in 40 CFR part
60, appendix B, and for the on-going QA tests, Procedure 2 to 40 CFR
part 60, appendix F, would be required.
    After consideration of comments received, the EPA has concluded
that all PM concentrations should be reported in units of measure that
are consistent with the PM CEMS correlation. For example, if the PM
CEMS measures in units of milligrams per actual cubic meter (mg/acm)
and the concentrations used to derive the correlation curve are in
those same units, then the hourly PM concentrations would be recorded
and reported in mg/acm. Section <IP_ADDRESS> of appendix C would also
require the reference method readings and the PM CEMS responses
obtained in the RRAs and RCAs to be reported in the same units of
measure as the PM CEMS correlation curve.
    Sections <IP_ADDRESS> and <IP_ADDRESS> would require PM concentrations and
emission rates (lb/MMBtu or lb/MWh) to be reported with one leading
non-zero digit and one decimal place, in scientific notation, rather
than reporting the

concentrations and rates to three significant figures. Conventional
rounding would be used, i.e., if the digit immediately following the
first decimal place is 5 or greater, the digit in the first decimal
place would be rounded upward (increased by one); if the digit
immediately following the first decimal place is 4 or less, the digit
in the first decimal place would remain unchanged.
    The proposed frequencies for the on-going QA tests and the rules
for data validation are presented in Section 5 of appendix C. In
response to numerous requests from commenters, the frequency and data
validation rules for the RCAs and RRAs are similar, but not identical
to, provisions of 40 CFR part 75. The frequency of these tests would
follow the familiar calendar quarter and grace period reporting plan.
An RRA would be required once every four calendar quarters and an RCA
would be required once every 12 calendar quarters. A grace period would
be provided (i.e., 720 operating hours or one calendar quarter,
whichever comes first), to cover cases where circumstances beyond the
control of the owner or operator prevent the required test from being
completed on schedule. In addition, as explained in detail below,
section 7.2.4 of appendix C would allow the use of provisional data for
up to 60 days after completion of an RRA, RCA, or PM CEMS correlation
test.
    The proposed procedures for calculating the PM emission rates in
units of the emission standard are found in section 6. These
calculation methods are basically the same as those used for Hg
monitoring systems and for HCl and HF CEMS in appendices A and B. The
proposed recordkeeping and reporting requirements are found in section
7. Section 7.1 proposed that monitoring plan records and hourly records
of operating parameters, PM concentration, diluent gas concentration,
stack gas flow rate and moisture content, and PM emission rate would be
kept. Sections 7.2.3 and 7.2.4, respectively, would require monitoring
plan information and the results of certification, recertification, and
QA tests to be reported electronically. For consistency with these
revisions to appendices A and B, section <IP_ADDRESS> would specify that for
new units or units installing PM CEMS in order to switch from another
MATS-compliant methodology to PM monitoring, the electronic monitoring
plan information would be submitted at least 21 days prior to the
commencement of certification testing. However, for units with
previously-certified PM CEMS that elect to implement PM monitoring, the
monitoring plan information could be submitted prior to or concurrent
with the first quarterly emissions report. Section 7.2.5 would require
quarterly electronic emissions reports to be submitted within 30 days
after the end of each calendar quarter. All electronic reports would be
submitted using the ECMPS Client Tool. However, for EGUs that have
begun using the PM CEMS compliance option prior to January 1, 2024,
electronic reporting of monitoring plan information, certification and
on-going QA test results, hourly PM emissions data, and the applicable
reference method data in appendix E would not begin until January 1,
2024, to allow time for software development and beta testing. Until
then, records of the required information and tests would be kept. For
EGUs that certify and begin using PM CEMS on or after January 1, 2024,
reporting of hourly PM emissions data would begin with the first
operating hour after successful completion of the initial PM CEMS
correlation test.
    For PM CEMS correlations, RRAs, and RCAs that are completed on and
after January 1, 2024, the applicable reference method data in sections
17 through 31 of appendix E would be submitted along with the
electronic test summary required under section 7.2.4 of appendix C. To
the extent practicable, the electronic test results and the appendix E
reference method data would be submitted prior to or concurrent with
the relevant quarterly electronic emissions report. However, the EPA
recognizes that this is not always possible, particularly when an RRA
or RCA is done near the end of a calendar quarter. The EPA test Methods
5 and 5D, unlike instrumental test methods, require laboratory analyses
of the collected samples and generally cannot provide test results
while the test team is on-site. In view of this, section 7.2.4 of
appendix C would allow the test results to be submitted up to 60 days
after the test completion date. ``Provisional'' status could be claimed
for the emissions data affected by the test, starting from the date and
hour in which the test was completed, and continuing until the date and
hour in which the test results are submitted. If the test is
successful, the status of the data in that time period would change
from provisional to quality-assured, and no further action is required.
However, if the test is unsuccessful, the provisional data would be
invalidated, and resubmission of the affected emission report(s) would
be required.

E. Addition of Appendix D

    We are proposing a second new appendix, i.e., appendix D, be added
to subpart UUUUU of 40 CFR part 63. Appendix D would set forth the
monitoring and reporting requirements for EGU owners or operators who
elect to use a PM CPMS to demonstrate continuous compliance.
Structurally, appendix D would be similar to appendices A, B, and C.
However, the criteria for system design and performance, the procedures
for determining operating limits, data reduction, and compliance
assessment, and certain recordkeeping requirements are not detailed in
the appendix; rather, the applicable sections of the MATS rule are
cross-referenced (see sections 2.1 through 2.4, 3.1 introductory text,
and section <IP_ADDRESS> of the appendix).
    Section <IP_ADDRESS> would require the ECMPS Client Tool to be used to
create and maintain an electronic monitoring plan. The PM CPMS would be
defined as a monitoring system with a unique system ID number. The
monitoring plan would also include the current operating limit (with
units of measure), the make, model, and serial number of the PM CPMS,
the analytical principle of the monitoring system, and monitor span and
range information.
    We are proposing to require operating parameter records for each
hour of operation of the affected EGUs, including the date and hour,
the EGU or stack operating time, and a flag to identify exempt startup
and shutdown hours. Hourly average PM CPMS output values would be
reported for each hour in which a valid value of the output parameter
is obtained, in units of milliamps, PM concentration, or other units of
measure, including the instrument's digital signal output equivalent. A
special code would be required to indicate operating hours in which
valid data are not obtained. The percent monitor data availability
would also be calculated in the manner established for SO2,
carbon dioxide (CO2), oxygen (O2), or moisture
monitoring systems in 40 CFR 75.32.
    Sections 3.2.2 and 3.2.3, respectively, would require notifications
(to be provided in accordance with section 63.10030) and electronic
monitoring plan submittals at specified times. For units using the PM
CPMS compliance option prior to January 1, 2024, the electronic
monitoring plan information would be submitted prior to or concurrent
with the first quarterly report. For units switching to the PM CPMS
compliance option on or after January 1, 2024, the electronic
monitoring plan would be submitted no

later than 21 days prior to the PM test that establishes the initial
operating limit. Section 3.2.4 would require the electronic quarterly
reports to be submitted within 30 days after the end of each calendar
quarter. Reporting of hourly responses from the PM CPMS would begin
either with the first operating hour of 2024 or the first operating
hour after completion of the stack test that establishes the initial
operating limit, whichever is later. Each quarterly report would
include a compliance certification with a statement by a responsible
official that to the best of his or her knowledge, the report is true,
accurate, and complete.
    In addition to the electronic quarterly reports, we are proposing
to require reporting of deviations from the operating limit in the
quarterly compliance reports required under 40 CFR 63.10031(g).
Further, section 3.2.5 of appendix D would require the results of each
performance stack test for PM that is used to establish an operating
limit to be reported electronically in the relevant quarterly
compliance report. For PM tests completed on and after January 1, 2024,
the applicable appendix E reference method data would also be submitted
along with the relevant quarterly compliance report.

F. Addition of Appendix E

    We are proposing to add a third new appendix, i.e., appendix E, to
subpart UUUUU of 40 CFR part 63. Sections 2 through 13 of appendix E
list the data elements that would be reported in XML format in the
quarterly compliance reports required under 40 CFR 63.10031(g),
starting with reports covering the first quarter of 2024.
    The MATS compliance strategy (e.g., whether the EGU owner or
operator elects to perform periodic stack testing, continuous
monitoring, or to use emissions averaging) and the events that occur
during each calendar quarter determine which data elements in sections
2 through 13 would be included in the quarterly compliance reports. As
noted in section V.A.(9), updated reporting instructions for these
compliance reports are found in the rule docket and are posted on the
CAMD and MATS websites.
    For reasons stated in the previous proposal's Response to Comments
document (which is available in the rule docket \4\), we are proposing
to retain the basic provisions of proposed sections 14 through 21 of
appendix E, requiring details of the reference methods used for
performance stack tests and continuous monitoring system performance
evaluations to be reported in XML format. The rule would also retain
the proposed requirement in section 22 of appendix E to provide
reference method test information that is incompatible with electronic
reporting as PDF files, although it has been renumbered as section 31
and modified to include a cross-reference to 40 CFR 63.7(g), which
describes the contents of a performance test report. The applicable
reference method information in appendix E would be provided for each
stack test; each RATA of a Hg, HCl, HF, or SO2 monitoring
system; and each RRA, RCA, or correlation test of a PM CEMS that is
completed on and after January 1, 2024.
---------------------------------------------------------------------------

    \4\ See EPA-HQ-OAR-2018-0794 at https://www.regulations.gov/.
---------------------------------------------------------------------------

    To address concerns raised by the commenters about portions of the
2016 proposed rule \5\ (the previous proposal), specifically, the
reporting requirements in sections 17 through 21 of proposed appendix
E, the Agency proposes to revise and reformat the data element lists to
correspond to the compliance options described in section 16 of
appendix E. Explicitly, sections 17 through 30 would replace previously
proposed sections 17 through 21. Commenters pointed out, and the Agency
concurs, that some of the previously proposed data elements are either
unnecessary, inapplicable to MATS, or duplicative of information in
other MATS reports; these elements are proposed to be removed from the
lists and include:
---------------------------------------------------------------------------

    \5\ As mentioned in footnote 1, see 81 FR 67062 from September
29, 2016.
---------------------------------------------------------------------------

     Previously proposed <IP_ADDRESS>.1 of appendix C to this
subpart;
     Previously proposed <IP_ADDRESS>.2 of appendix C to this
subpart;
     Previously proposed <IP_ADDRESS>.3 of appendix C to this
subpart;
     Previously proposed <IP_ADDRESS> of appendix C to this subpart;
     Previously proposed 10.4 of appendix E to this subpart;
     Previously proposed 10.5.1 of appendix E to this subpart;
     Previously proposed 10.5.2 of appendix E to this subpart;
     Previously proposed 10.5.7 of appendix E to this subpart;
     Previously proposed 17.28 of appendix E to this subpart;
     Previously proposed 17.30 of appendix E to this subpart;
     Previously proposed 17.37 of appendix E to this subpart;
     Previously proposed 18.21 of appendix E to this subpart;
     Previously proposed 19.29 of appendix E to this subpart;
     Previously proposed 20.4 of appendix E to this subpart;
     Previously proposed 20.15 of appendix E to this subpart;
     Previously proposed 20.17 of appendix E to this subpart;
     Previously proposed 20.21 of appendix E to this subpart;
     Previously proposed 20.25 of appendix E to this subpart;
     Previously proposed 20.30 of appendix E to this subpart;
     Previously proposed 20.36 of appendix E to this subpart;
     Previously proposed 20.37 of appendix E to this subpart;
     Previously proposed 20.41 of appendix E to this subpart;
     Previously proposed 20.42 of appendix E to this subpart;
     Previously proposed 20.44 of appendix E to this subpart;
     Previously proposed 20.46 of appendix E to this subpart;
     Previously proposed 20.52 of appendix E to this subpart;
     Previously proposed 21.14 of appendix E to this subpart;
and
     Previously proposed 21.28 of appendix E to this subpart.
    Reporting instructions for sections 17 through 30 have been
developed. These proposed, draft example instructions are included in
the rule docket and are posted on the MATS and CAMD websites.
    The reorganized data element lists and corresponding instructions
clarify which data elements are proposed to be reported for each
compliance option and explain how the data are to be reported. Several
new data elements are proposed for the lists, to enable the ECMPS
Client Tool to be used, to enhance the quality of the data, and to
facilitate compliance. As mentioned in VI.C of this preamble, this
proposed action is expected to reduce overall annual source burden. The
Agency believes that the proposed addition of these data elements is
offset by the proposed removal of others, the proposed change to a
consistent submission frequency, and the proposed merger of separate
electronic reporting systems into just one electronic reporting system
such that overall annual source reporting burden is reduced by 11,000
hours. The proposed new data elements to be reported are as follows:
     ``Part.'' The previous proposal would only have required
the ``Subpart'' to be reported. To avoid any possible confusion with
other EPA regulations, both the CFR part (63) and subpart (UUUUU) need
to be included in the reports.
     ``APS Flags.'' For 3-level pre-test calibrations, system
bias, and drift checks, instrumental EPA test Methods

3A and 6C require certain acceptance criteria to be met. For each of
these tests, there is a main PS and an alternative specification. The
main PS is expressed as a percentage of span, while the alternative
specification is the absolute difference between a reference value and
the measured value. In view of this, it is important to know which
specification has been applied to ascertain whether the test was
successful or not. Therefore, alternative performance specification
(APS) flags are proposed to be added for the pre- and post-test
calibrations, bias checks, and drift checks. An APS flag of ``0''
indicates that the reported test result is based on the main
performance specification, whereas an APS flag of ``1'' means that the
reported result is based on the alternative specification.
     ``Test Comment.'' This text field is proposed to be added
to allow the affected sources to provide additional, pertinent
information about a particular test.
     ``Run Begin Date'' and ``Run End Date.'' These two data
elements are proposed to replace the previous proposed element ``Run
Date'' to cover cases where a test run begins on one day and ends on
another (e.g., if a run begins late at night and ends early the next
morning).
     ``Converted Concentration and Units of Measure.'' These
proposed data elements apply to correlation tests and performance
audits (RRAs and RCAs) of PM CEMS. The reference method used for these
tests is EPA test Method 5 (or, if applicable, 5D). The PM
concentrations obtained from EPA test Method 5 or 5D are expressed in
units of grams per dry standard cubic meter (g/dscm). However,
consistent with section 8.6 of PS 11, appendix C of MATS proposes to
require all PM concentrations to be reported in units of measure that
are consistent with the PM CEMS correlation curve. Most PM CEMS measure
concentration in units of milligrams per actual cubic meter (mg/acm);
others may measure at a certain temperature (e.g., mg/acm at 160
[deg]Celsius), and still others may measure on a dry basis. Therefore,
in addition to reporting the EPA test Method 5 test results in units of
g/dscm, the converted PM concentrations would be reported in units
consistent with the PM CEMS correlation curve.
     ``Average Sampling Rate and Units of Measure.'' These
proposed data elements are specific to EPA test Method 30B. That EPA
test Method 30B requires a post-test leak check of each sampling train.
The leakage rate must not exceed 4 percent of the average sampling
rate. Therefore, to assess compliance with this specification, both the
leakage rate and the average sampling rate would be reported. The
previous proposed rule only required the leakage rate to be reported.
     ``Control Device Code.'' This proposed data element refers
to the control device code or control technology National Emission
Inventory (NEI) code associated with the EGU (or group of EGUs sharing
a common stack). Providing this data element would help in EGU
categorization and emission factor development.
     ``Corresponding Reference Method(s), if applicable.'' This
proposed data element allows pollutant reference method run data to be
associated with concurrent measurements of the stack gas flow rate
using EPA test Method 2, and/or CO2 or O2
concentration using EPA test Method 3A, and/or stack gas moisture
content using EPA test Method 4. Reporting this data element is
necessary to ensure test methods were conducted properly so that
emission rates can be calculated.
     ``Corresponding Reference Method(s) Run Number, if
applicable.'' This proposed data element provides the run number of
concurrent reference method tests. The assigned run number of the EPA
test Method 1 through 4 or EPA test Method 3A tests conducted at the
same time as a reference method test needs to be reported in order to
ensure the methods were conducted properly so that emission rates can
be calculated.
     ``Pollutant Concentration Units of Measure.'' This
proposed data element provides the appropriate units of measure code
for the pollutant or analyte concentration, and reporting it is
necessary for comparison to the standard.
     ``Pollutant Emission Rate.'' This proposed data element is
the pollutant emission rate expressed in the units of the standard, and
reporting it is necessary for comparison with the standard.
     ``Pollutant Emission Rate Units of Measure (in units of
the standard).'' This proposed data element is the units of the
standard specified in Table 1 or 2 of this subpart. Reporting it is
necessary for comparison to the standard.
     ``Process Parameter Units of Measure.'' This proposed data
element identifies the process rate parameter unit of measure: GWh/h,
MWh/h, TBtu/h, or MMBTU/h, and reporting it is necessary to ensure
accurate comparisons between runs and for emission factor development
purposes.
     ``Total Pollutant Mass Trap A'' and ``Total Pollutant Mass
Trap B.'' These proposed data elements refer to the total mercury mass
measured by Train A and Train B, respectively, in the appropriate units
of measure. Reporting these values is necessary for quality assurance
purposes and for comparison with the standard.
     ``Method Detection Limit (MDL).'' This proposed data
element refers to the minimum amount of analyte that can be detected
and reported. Reporting it is necessary for calculation checks and for
emissions factor development purposes.
     ``Percent Spike Recovery.'' This proposed data element
refers to the spike recovery in percent, which is required to be
reported by section <IP_ADDRESS> in EPA test Method 30B using Equation 30B-
1.
     ``F-Factor (Fc).'' This proposed data element
expands the current F-factor choices to include the carbon F-Factor,
which is based on the ratio of CO2 to heat content of fuel.
Reporting it allows conversion from mass per volume to mass per heat
input for those who choose to use emissions testing.
     ``Compliance Limit Basis (Heat Input or Electrical
Output).'' This proposed data element identifies the denominator of the
compliance units selected for an existing EGU by its owner or operator.
Reporting this decision is necessary for comparison of results with the
standard.
     ``Heat Input or Electrical Output Unit of Measure.'' This
proposed data element specifies the denominator of the compliance unit
that corresponds to the means of compliance selected for an existing
EGU by its owner or operator. Reporting this unit is necessary for
comparison of results with the standard and for emission factor
development purposes.
     ``Pollutant Concentration.'' This proposed data element
expands the already-existing ``Emissions Concentration'' data element
to include pollutants. Reporting this data element is necessary for
comparison of results with the standard and for emission factor
development purposes.
     ``Stack Gas Flow Rate--dscfm.'' This proposed data element
clarifies the already-existing ``Volumetric Flow Rate--scfm'' data
element so that reporters will know to report their EGU's dry stack gas
flow rate. Reporting this data element is necessary for calculation
purposes. Several commenters \6\ on the September 29, 2016, proposed
rule (i.e., the previous proposal) stated that those proposed revisions
included a significant amount of duplicative reporting, which should be
eliminated. In response to the

concerns expressed by the commenters, the Agency examined the XML data
element lists for stack tests and CMS performance evaluations in order
to identify duplicative reporting and eliminate it where possible. The
following evaluations were made:
---------------------------------------------------------------------------

    \6\ Commenters 20612, 20597, and 20609 on Docket ID No. EPA-HQ-
OAR-2009-0234.
---------------------------------------------------------------------------

    First, the data elements in sections 2 through 13 of appendix E
(for the quarterly compliance reports) were compared against the data
elements in sections 17 through 30 of appendix E (corresponding to the
detailed reference method data for stack tests and CMS performance
evaluations). The two lists were found to have 20 data elements in
common, but at least 9 of these elements (i.e., Source ID (Sampling
Location), Test Number, Run Number, Run Begin Date, and a few others)
are proposed to be included in both XML schemas to properly link the
individual stack test summaries in the compliance report with the
corresponding reference method data.
    Second, the data elements listed in the reporting sections of
appendices A, B, and C of MATS, requiring the results of CMS
performance evaluations (i.e., RATAs, RRAs, and RCAs) to be reported
using the ECMPS Client Tool, were compared against the corresponding
reference method data elements in sections 17 through 30 of appendix E.
Only 12 data elements common to the appendix E and ECMPS Client Tool
schemas were found. This is not surprising because appendices A, B, and
C require only summarized results of CMS performance evaluations--
details of the Reference Method tests are not reported. Of the 12 data
elements common to the appendix E and ECMPS lists, 10 of them are
proposed to be included in both schemas to properly link the CMS test
summaries with the corresponding reference method data. In view of
these two evaluations, EPA concludes that most of the duplicative
reporting found among the various data element lists is necessary to
ensure that the results of stack tests and CMS performance evaluations
summarized in the quarterly compliance reports and the QA test
submittals to the ECMPS Client Tool can be matched with the
corresponding Reference Method data. Further, the remainder of the
duplicative reporting is minimal, rather than ``significant'' as
asserted by the commenters. The Agency believes that it is best not to
modify the data element lists to eliminate this small amount of
duplicate reporting. Although the deadlines for submitting the
quarterly compliance reports and the corresponding reference method
data are the same (i.e., within 60 days after the end of the quarter),
the two XML reports might not be submitted concurrently. So, if, for
instance, the compliance report is submitted prior to the reference
method data, and certain data elements are found only in the reference
method report, a thorough assessment of compliance may not be possible
until the reference method report is received. Similar considerations
apply to the summarized CMS performance evaluations in the ECMPS Client
Tool and the corresponding reference method data, if the two XML
reports are not submitted concurrently.

VI. Proposed Revisions to Other Rule Text

    The revisions to 40 CFR 63.10031 necessitate changes to other
sections of the rule to ensure that the rule is internally consistent.
Based on comments received, revisions have also been made to clarify
certain reporting requirements, to rectify inadvertent omissions, and
to correct inconsistencies. The affected rule sections are as follows:
    (a) We are proposing to revise the introductory text of paragraphs
(a)(2) and (b) of 40 CFR 63.10005. The amendment to paragraph (a)(2)
would clarify that Hg compliance may either be determined on either a
30- or 90-boiler operating day rolling average basis. For consistency
with appendix E, revised paragraph (b) notes that when auxiliary stack
gas flow rate or moisture data are needed to supplement a performance
stack test conducted with an isokinetic method such as EPA test Method
5 or EPA test Method 26A, separate EPA test Method 2 or EPA Method 4
tests are not needed to satisfy the requirements of 40 CFR 63.10007 and
Table 5. Data from the isokinetic method can be used to determine the
stack gas flow rate and moisture content.
    (b) We are proposing to amend 40 CFR 63.10009 as follows. The
second and third sentences in paragraph (a)(2) would be revised to
clarify the types of data that may be used to determine WAERs. Data
from Hg CEMS, sorbent trap monitoring systems, but not LEE tests, may
be used for Hg emissions averaging. For other pollutants, both CEMS
data and stack test data may be used. The last sentence of paragraph
(a)(2) would be amended to clarify that if any EGU in an averaging
group operates on any of the days in a 30- or 90-group boiler operating
day compliance period (regardless of how many or how few), the
emissions data from that EGU on those days must be included in the
weighted average. Since averaging of Hg emissions is permitted on a 30-
group boiler operating day basis, Equations 2a and 2b in 40 CFR
63.10009 apply to Hg as well as other pollutants. Therefore, the words
``for pollutants other than Hg'' would be removed from the introductory
text of paragraph (b)(2), and in the nomenclature of Equation 2a, the
words ``or sorbent trap monitoring'' would be added after the words
``unit i's CEMS'' in the definition of the term ``Heri.''
Finally, for completeness, Equations 3a and 3b would be amended by
removing the terms that pertain to quarterly stack testing. Equations
3a and 3b apply only to the 90-group boiler operating day Hg WAER limit
for coal-fired units. Coal-fired EGUs do not have the option to use
quarterly stack testing to demonstrate compliance; if a coal unit does
not qualify as a LEE, Hg emissions must be continuously monitored.
    (c) As explained in section IV.A(11) above, we are proposing to
revise paragraphs (h)(6) and (7), (i), and (j)(4)(i) and (ii) of 40 CFR
63.10010 to resolve inconsistencies in the text.
    (d) We are proposing to revise 40 CFR 63.10011(e) to require
Notifications of Compliance Status for initial compliance
demonstrations to include the information specified in 40 CFR
63.10030(e), and to be submitted in accordance with 40 CFR
63.10031(f)(4) or (h), as applicable. This proposed change is necessary
to cover initial Notifications of Compliance Status for both new and
existing EGUs. The interim reporting process described in 40 CFR
63.10031(f)(4) and the on-going reporting process in 40 CFR 63.10031(h)
require these Notifications to be submitted as PDF files, through
ECMPS.
    (e) We are proposing to revise 40 CFR 63.10011(g)(3), 40 CFR
63.10021(i), and two sentences in Items 3 and 4 of Table 3 to be
consistent with 40 CFR 63.10031(i) and Table 8. For EGU owners or
operators relying on paragraph (2) of the definition of ``startup'' in
40 CFR 63.10042, 40 CFR 63.10031(i) retains the requirement for the
parametric data and other information in 40 CFR 63.10031(c)(5) to be
included in the semiannual compliance reports, for startup and shutdown
incidents that occur during the interim reporting period. However, in
view of the proposed phase-out of the semiannual compliance reports,
for startup and shutdown incidents that occur during each subsequent
calendar quarter, starting with the first quarter of 2024, the
supplementary information in 40 CFR 63.10031(c)(5)(ii) and 63.10020(e)
would be required to be provided as a separate PDF submittal, along
with the quarterly compliance report. As previously noted, the
requirements in 40 CFR

63.10031(c)(5)(iii), (iv), and (v) to report hourly average CEMS and
operating parameter values for startup and shutdown events are not
proposed to be incorporated into this PDF report because they are
duplicative of the hourly values reported under appendices A through D.
Startup and shutdown hours are flagged in the quarterly emissions
reports and can be identified for auditing purposes.
    (f) We are proposing revisions to paragraphs (e)(9), (f), and
(h)(3) of 40 CFR 63.10021 as follows. Paragraph (e)(9) is unchanged
from the previous proposal, except that the December 31, 2017, and
January 1, 2018, transition dates are replaced with December 31, 2023,
and January 1, 2024, respectively. We are proposing to remove
references to the EPA's ERT and the CEDRI interface from paragraph (f)
and replace it with a general statement requiring all applicable
notifications and reports to be submitted through the ECMPS Client
Tool. We are proposing to add three statements at the end of paragraph
(f). The first statement, regarding a submission deadline that occurs
on a weekend or Federal holiday, extends the deadline to the next
business day. The second statement addresses a submission deadline that
occurs when the ECMPS system is offline for maintenance; in that case,
the deadline is extended until the first business day after the system
outage. The third statement clarifies that using the ECMPS Client Tool
to submit a required MATS report or notification satisfies the
requirement in 40 CFR 63.13 of the General Provisions to submit that
same report or notification (or the information contained in it) to the
appropriate EPA Regional office or state agency whose delegation
request has been approved. Finally, we are proposing to remove
paragraph (h)(3) because it is redundant with paragraph (i) and,
therefore, unnecessary.
    (g) We are proposing to remove 40 CFR 63.10030(e)(7)(i) for the
following reasons. The requirement in the current rule for an initial
Notification of Compliance Status to include summarized results of
annual and triennial performance tests which have not been done yet is
in an incorrect location. The requirement to submit these test
summaries belongs in 40 CFR 63.10031, not 40 CFR 63.10030. Text similar
to 40 CFR 63.10030(e)(7)(i) does, in fact, exist in 40 CFR 63.10031.
Specifically, 40 CFR 63.10031(c)(7) requires the annual and triennial
test results to be summarized in the semiannual compliance reports.
Note, however, that when the semiannual compliance reports are phased
out in 2024, the requirement to provide summarized results of these
tests does not end; the test summaries must be included in the
quarterly compliance reports under 40 CFR 63.10031(g).
    We are proposing to amend 40 CFR 63.10030(e)(7)(iii) to rectify an
inadvertent oversight. In the 2016 Technical Corrections rule package,
the EPA proposed a set of conditions that would allow an EGU owner or
operator to submit a request for permission to switch from a heat
input-based standard to an output-based standard. One of the proposed
conditions, in paragraph (e)(7)(iii)(A)(3) required a demonstration of
compliance with both emission limits, based on ``performance stack test
results completed within 30 days prior to'' the request. A commenter
objected to limiting this demonstration to ``stack test'' data and
asked the EPA to allow any data collected up to 45 days prior to the
request, including CEMS data, to be used. In the Response to Comments
document, the EPA agreed with these commenters, but did not make the
necessary changes to paragraph (e)(7)(iii)(A)(3) in the final rule.
This rule corrects this oversight. In addition, we are proposing to add
a note to paragraph (e)(7)(iii) to clarify that requests to switch from
one standard to the other are made subsequent to, and are not part of,
the initial Notification of Compliance Status.
    (h) We are proposing to amend 40 CFR 63.10032(a) to include
references to the recordkeeping required under new appendices C (for PM
CEMS), D (for PM CPMS), and E (for quarterly compliance reports and
reference method test data). Also, in view of the move away from
semiannual compliance reporting to quarterly reporting, we are
proposing to replace the term ``semiannual compliance report'' with
references to both semiannual and quarterly compliance reports in
paragraph (a)(1).
    (i) We are proposing to remove the words ``or out of control
period'' from 40 CFR 63.10042, from the definition of ``monitoring
system malfunction or out of control period'' because that definition
does not describe an out of control period. We are proposing to add a
separate definition of ``out-of-control period,'' and that definition
is similar with the definition provided in the Acid Rain Program
definitions at 40 CFR 72.2.
    (j) We are proposing to revise Table 8 to subpart UUUUU of 40 CFR
part 63 to be consistent with the amendments to 40 CFR 63.10031 and the
proposed addition of appendices C, D, and E.
    (k) Finally, we are proposing to revise the recordkeeping and
reporting requirements in Table 9 to 40 CFR part 63, subpart UUUUU, as
follows. First, we are proposing changes to the requirement to provide
the information in 40 CFR 63.10030(e)(1) through (8), i.e., it only
applies to initial Notifications of Compliance Status; subsequent
notifications are not required. Second, in keeping with the earlier
discussion provided in section IV.A of this preamble, we are proposing
to add a statement to clarify that the excess emissions recordkeeping
and reporting requirements of 40 CFR 63.10(c)(7) and (8) and (e)(3)(v)
and (vi) apply through December 31, 2023, when the semiannual
compliance reports are phased out. On and after January 1, 2024, all
relevant information will be provided in quarterly, as opposed to
semiannual, reports.

VII. Statutory and Executive Order Reviews

    Additional information about these statutes and Executive orders
can be found at https://www.epa.gov/laws-regulations/laws-and-executive-orders.

A. Executive Order 12866: Regulatory Planning and Review and Executive
Order 13563: Improving Regulation and Regulatory Review

    This action is not a significant regulatory action and was,
therefore, not submitted to the Office of Management and Budget (OMB)
for review.

B. Executive Order 13771: Reducing Regulations and Controlling
Regulatory Costs

    This action is considered an Executive Order 13771 deregulatory
action. Details on the estimated cost savings of this proposed rule can
be found in the EPA's analysis of the potential costs and benefits
associated with this action.

C. Paperwork Reduction Act (PRA)

    The information collection activities in this proposed rule have
been submitted for approval to OMB under the PRA. The Information
Collection Request (ICR) document that the EPA prepared has been
assigned EPA ICR number 2137.09. You can find a copy of the ICR in the
docket for this proposed rule, and it is briefly summarized here.
    Respondents/affected entities: The respondents are owners or
operators of fossil fuel-fired EGUs. The United States Standard
Industrial Classification code for respondents affected by the rule is
4911 (Electric Services). The corresponding NAICS code is 2211100
(Electric Power Generation, Transmission, and Distribution).
    Respondent's obligation to respond: Mandatory per 42 U.S.C. 7414 et
seq.

    Estimated number of respondents: 1,414.
    Frequency of response: Quarterly for compliance reports.
    Total estimated burden: Reduction of 11,000 hours (per year).
Burden is defined at 5 CFR 1320.3(b).
    Total estimated cost: Savings of $15,079,000 (per year), includes
$0 annualized capital or operation and maintenance costs.
    An agency may not conduct or sponsor, and a person is not required
to respond to, a collection of information unless it displays a
currently valid OMB control number. The OMB control numbers for the
EPA's regulations in 40 CFR are listed in 40 CFR part 9.
    Submit your comments on the Agency's need for this information, the
accuracy of the provided burden estimates, and any suggested methods
for minimizing respondent burden to the EPA using the docket identified
at the beginning of this rule. You may also send your ICR-related
comments to OMB's Office of Information and Regulatory Affairs via
email to<EMAIL_ADDRESS>Attention: Desk Officer for the
EPA. Since OMB is required to make a decision concerning the ICR
between 30 and 60 days after receipt, OMB must receive comments no
later than May 11, 2020. The EPA will respond to any ICR-related
comments in the final rule.

D. Regulatory Flexibility Act (RFA)

    I certify that this action will not have a significant economic
impact on a substantial number of small entities under the RFA. In
making this determination, the impact of concern is any significant
adverse economic impact on small entities. An agency may certify that a
rule will not have a significant economic impact on a substantial
number of small entities if the rule relieves regulatory burden, has no
net burden, or otherwise has a positive economic effect on the small
entities subject to the rule. For purposes of assessing the impacts of
this rule on small entities, the EPA considered small entities to be
defined as: (1) A small business that is an electric utility producing
4 billion kilowatt-hours or less as defined by NAICS codes 221122
(fossil fuel-fired electric utility steam generating units) and 921150
(fossil fuel-fired electric utility steam generating units in Indian
country); (2) a small governmental jurisdiction that is a government of
a city, county, town, school district, or special district with a
population of less than 50,000; and (3) a small organization that is
any not-for-profit enterprise which is independently owned and operated
and is not dominant in its field. As required by the RFA, the EPA
proposed using this alternative definition in the Federal Register of
May 3, 2011, 76 FR 25083, sought public comment, consulted with the
Small Business Administration and finalized the alternative definition
in the Federal Register of February 16, 2012, 77 FR 9433. As stated in
that document, the alternative definition would apply to this
regulation. This action reduces annual burden on small and large
entities. We have, therefore, concluded that this action will relieve
regulatory burden for all directly regulated small entities.

E. Unfunded Mandates Reform Act (UMRA)

    This action does not contain an unfunded mandate of $100 million or
more as described in UMRA, 2 U.S.C. 1531-1538, and does not
significantly or uniquely affect small governments.
    As described earlier, this action reduces annual burden on
governments already subject to MATS; as a result, we have determined
that this action will not result in any ``significant'' adverse
economic impact for small governments.

F. Executive Order 13132: Federalism

    This action does not have federalism implications. It will not have
substantial direct effects on the states, on the relationship between
the National Government and the states, or on the distribution of power
and responsibilities among the various levels of government.

G. Executive Order 13175: Consultation and Coordination With Indian
Tribal Governments

    This action does not have tribal implications as specified in
Executive Order 13175. As described earlier, this action has no
substantial direct effect on Indian tribes already subject to MATS,
since this action reduces their annual burden. Thus, Executive Order
13175 does not apply to this action.

H. Executive Order 13045: Protection of Children From Environmental
Health Risks and Safety Risks

    The EPA interprets Executive Order 13045 as applying only to those
regulatory actions that concern environmental health or safety risks
that the EPA has reason to believe may disproportionately affect
children, per the definition of ``covered regulatory action'' in
section 2-202 of the Executive order. This action is not subject to
Executive Order 13045 because it does not concern an environmental
health risk or safety risk.

I. Executive Order 13211: Actions Concerning Regulations That
Significantly Affect Energy Supply, Distribution or Use

    This action is not subject to Executive Order 13211, because it is
not a significant regulatory action under Executive Order 12866.

J. National Technology Transfer and Advancement Act (NTTAA)

    This rulemaking does not involve technical standards.

K. Executive Order 12898: Federal Actions To Address Environmental
Justice in Minority Populations and Low-Income Populations

    The EPA believes that this proposed action is not subject to
Executive Order 12898 (59 FR 7629, February 16, 1994) because it would
not establish an environmental health or safety standard. This proposed
regulatory action revises the way in which information is reported to
the Agency, increasing submission frequency and making adaptions so
that just one reporting system can be used, but reducing overall
burden; this regulatory action does not have any impact on human health
or the environment.

List of Subjects in 40 CFR Part 63

    Environmental protection, Administrative practice and procedure,
Air pollution control, Hazardous substances, Intergovernmental
relations, Reporting and recordkeeping requirements.

Andrew Wheeler,
Administrator.

    For the reasons set forth in the preamble, EPA proposes to amend 40
CFR part 63 as follows:

PART 63--NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS
FOR SOURCE CATEGORIES

0
1. The authority citation for part 63 continues to read as follows:

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

Subpart UUUUU--National Emission Standards for Hazardous Air
Pollutants: Coal- and Oil-Fired Electric Utility Steam Generating
Units

Sec.  63.10000  [Amended]

0
2. In Sec.  63.10000, paragraph (d)(5)(vi) is amended by adding the
words ``, where appropriate,'' immediately after the words ``CMS that
is out of control consistent with Sec.  63.8(c)(7)(i)''.
0
3. Section 63.10005 is amended by:

0
a. Revising the first sentence in paragraph (a)(2) introductory text;
and
0
b. Revising paragraph (b) introductory text.
    The revisions read as follows:

Sec.  63.10005  What are my initial compliance requirements and by what
date must I conduct them?

    (a) * * *
    (2) To demonstrate initial compliance using either a CMS that
measures HAP concentrations directly (i.e., an Hg, HCl, or HF CEMS, or
a sorbent trap monitoring system) or an SO2 or PM CEMS, the
initial performance test shall consist of 30- or, if applicable for Hg,
90-boiler operating days. * * *
* * * * *
    (b) Performance testing requirements. If you choose to use
performance testing to demonstrate initial compliance with the
applicable emissions limits in Tables 1 and 2 to this subpart for your
EGUs, you must conduct the tests according to Sec.  63.10007 and Table
5 to this subpart. Notwithstanding the requirements in this subpart,
when Table 5 specifies the use of isokinetic EPA test Method 5, 5D,
26A, or 29 in appendices A-3 and A-8 to part 60 of this chapter for a
stack test, if concurrent measurement of the stack gas flow rate or
moisture content is needed to convert the pollutant concentrations to
units of the standard, separate determination of these parameters using
EPA test Method 2 or EPA test Method 4 in appendices A-1 and A-3 to
part 60 of this chapter is not necessary. Instead, the stack gas flow
rate and moisture content can be determined from data that are
collected during the EPA test Method 5, 5D, 6, 26A, or 29 test (e.g.,
pitot tube (delta P) readings, moisture collected in the impingers,
etc.). For the purposes of the initial compliance demonstration, you
may use test data and results from a performance test conducted prior
to the date on which compliance is required as specified in Sec.
63.9984, provided that the following conditions are fully met:
* * * * *
0
4. Section 63.10009 is amended by:
0
 a. Revising in paragraph (a)(2) the second, third, and last sentences;
0
 b. In paragraph (b)(2):
0
i. In the introductory text, removing the words ``for pollutants other
than Hg''; and
0
 ii. Adding in the definition for ``Heri'' the words ``or
sorbent trap monitoring system'' after the words ``unit i's CEMS''; and
0
c. Revising ``Equation 3a'' and ``Equation 3b'' in paragraph (b)(3).
    The revisions read as follows:

Sec.  63.10009   May I use emissions averaging to comply with this
subpart?

    (a) * * *
    (2) * * * Note that except for the alternate Hg emissions limit
from EGUs in the ``unit designed for coal >= 8,300 Btu/lb''
subcategory, the averaging time for emissions averaging for pollutants
is 30-group boiler operating days (rolling daily) using data from CEMS
and sorbent trap monitoring (for Hg), or a combination of data from
CEMS and emissions testing (for other pollutants). The averaging time
for emissions averaging for the alternate Hg limit (equal to or less
than 1.0 lb/TBtu or 1.1E-2 lb/GWh) from EGUs in the ``unit designed for
coal >= 8,300 Btu/lb'' subcategory is 90-group boiler operating days
(rolling daily) using data from CEMS, sorbent trap monitoring, or a
combination of data from CEMS and sorbent trap monitoring. * * * You
must calculate the weighted average emissions rate for the group in
accordance with the procedures in this paragraph (a)(2) using the data
from all units in the group including any that operate fewer than 30
(or 90) of the preceding 30 (or 90) group boiler operating days.
* * * * *
    (b) * * *
    (3) * * *
    [GRAPHIC] [TIFF OMITTED] TP10AP20.001

Where:

Heri = Hourly emission rate from unit i's Hg CEMS or Hg
sorbent trap monitoring system for the preceding 90-group boiler
operating days;
Rmi = Hourly heat input or gross output from unit i for
the preceding 90-group boiler operating days;
p = Number of EGUs in the emissions averaging group; and
n = Number of hours that hourly rates are collected over the 90-
group boiler operating days.
[GRAPHIC] [TIFF OMITTED] TP10AP20.002

Where:

Heri = Hourly emission rate from unit i's Hg CEMS or Hg
sorbent trap monitoring system for the preceding 90-group boiler
operating days;
Smi = Steam generation in units of pounds from unit i
that uses Hg CEMS or Hg sorbent trap monitoring for the preceding
90-group boiler operating days;
Cfmi = Conversion factor, calculated from the most recent
compliance test results, in units of heat input per pound of steam
generated or gross output per pound of steam generated, from unit i
that uses Hg CEMS or sorbent trap monitoring from the preceding 90-
group boiler operating days;
p = Number of EGUs in the emissions averaging group; and
n = Number of hours that hourly rates are collected over the 90-
group boiler operating days.
* * * * *
0
5. Section 63.10010 is amended by revising paragraphs (h)(6) and (7),
(i), and (j)(4) to read as follows:

Sec.  63.10010  What are my monitoring, installation, operation, and
maintenance requirements?

* * * * *
    (h) * * *
    (6) You must use all the data collected during all boiler operating
hours in assessing the compliance with your operating limit except:
    (i) Any data recorded during periods of monitoring system
malfunctions or repairs associated with monitoring system malfunctions.
You must report any monitoring system malfunctions as deviations in
your compliance reports under Sec.  63.10031(c) or (g) (as applicable);
    (ii) Any data recorded during periods when the monitoring system is
out-of-control (as specified in your site-specific monitoring plan),
repairs associated with periods when the monitoring system is out of
control, or required monitoring system quality assurance or quality
control activities conducted during out-of-control periods. You must
report any such periods as deviations in your compliance reports under
Sec.  63.10031(c) or (g) (as applicable);
    (iii) Any data recorded during required monitoring system quality
assurance or quality control activities that temporarily interrupt the
measurement of output data from the PM CPMS; and
    (iv) Any data recorded during periods of startup or shutdown.
    (7) You must record and report the results of PM CPMS system
performance audits, in accordance with Sec.  63.10031(k). You must also
record and make available upon request the dates and duration of
periods from when the PM CPMS is out of control until completion of the
corrective actions necessary to return the PM CPMS to operation
consistent with your site-specific monitoring plan.
    (i) If you choose to comply with the PM filterable emissions limit
in lieu of metal HAP limits, you may choose to install, certify,
operate, and maintain a PM CEMS and record and report the output of the
PM CEMS as specified in paragraphs (i)(1) through (8) of this section.
Compliance with the applicable PM emissions limit in Table 1 or 2 to
this subpart is determined on a 30-boiler operating day rolling average
basis.
    (1) You must install and certify your PM CEMS according to section
4 of appendix C to this subpart.
    (2) You must operate, maintain, and quality-assure the data from
your PM CEMS according to section 5 of appendix C to this subpart.
    (3) You must reduce the data from your PM CEMS to hourly averages
in accordance with section 6.1 of appendix C to this subpart.
    (4) You must collect data using the PM CEMS at all times the
process unit is operating except for periods of monitoring system
malfunctions, out-of-control periods, repairs associated with
monitoring system malfunctions or out-of-control periods, and required
monitoring system quality assurance, quality control, or maintenance
activities.
    (5) You must use all the data collected during all boiler operating
hours in assessing the compliance with your emissions limit except:
    (i) Any data recorded during periods of monitoring system
malfunctions and repairs associated with monitoring system
malfunctions. You must report any monitoring system malfunctions as
deviations in your compliance reports under Sec.  63.10031(c) or (g)
(as applicable);
    (ii) Any data recorded during periods when the monitoring system is
out-of-control (as specified in appendix C to this subpart), repairs
associated with periods when the monitoring system is out of control,
or required monitoring system quality assurance or quality control
activities conducted during out-of-control periods. You must report any
such periods as deviations in your compliance reports under Sec.
63.10031(c) or (g) (as applicable);
    (iii) Any data recorded during required monitoring system quality
assurance, quality control, or maintenance activities that temporarily
interrupt the measurement of emissions (e.g., calibrations, certain
audits, routine probe maintenance); and
    (iv) Any data recorded during periods of startup or shutdown.
    (6) You must keep records and report data from your PM CEMS in
accordance with section 7 of appendix C to this subpart.
    (7) You must record and make available upon request the dates and
duration of periods when the PM CEMS is out-of-control to completion of
the corrective actions necessary to return the PM CEMS to operation
consistent with your site-specific monitoring plan.
    (8) You must calculate each 30-boiler operating day rolling average
PM emission rate in units of the applicable emissions limit in Table 1
or 2 to this subpart, in accordance with section 6.2.4 of appendix C to
this subpart.
    (j) * * *
    (4) You must collect data using the HAP metals CEMS at all times
the process unit is operating and at the intervals specified in
paragraph (a) of this section, except for periods of monitoring system
malfunctions, out-of-control periods, repairs associated with
monitoring system malfunctions or out-of-control periods, and required
monitoring system quality assurance, quality control, or maintenance
activities.
    (i) You must use all the data collected during all boiler operating
hours in assessing the compliance with your emission limit except:
    (A) Any data collected during periods of monitoring system
malfunctions and repairs associated with monitoring system
malfunctions. You must report any monitoring system malfunctions as
deviations in your compliance reports under Sec.  63.10031(c) or (g)
(as applicable);
    (B) Any data collected during periods when the monitoring system is
out of control as specified in your site-specific monitoring plan,
repairs associated with periods when the monitoring system is out of
control, or required monitoring system quality assurance or quality
control activities conducted during out-of-control periods. You must
report any out of control periods as deviations in your compliance
reports under Sec.  63.10031(c) or (g) (as applicable);
    (C) Any data recorded during required monitoring system quality
assurance or quality control activities that temporarily interrupt the
measurement of emissions (e.g., calibrations, certain audits, routine
probe maintenance); and
    (D) Any data recorded during periods of startup or shutdown.
    (ii) You must record and report the results of HAP metals CEMS
system performance audits, in accordance with Sec.  63.10031(k) You
must also record and make available upon request the dates and duration
of periods when the HAP metals CEMS is out of control to completion of
the corrective actions necessary to return the HAP metals CEMS to
operation consistent with your site-specific performance evaluation and
quality control program plan.
* * * * *
0
 6. Section 63.10011 is amended by revising paragraphs (e) and (g)(3)
to read as follows:

Sec.  63.10011  How do I demonstrate initial compliance with the
emissions limits and work practice standards?

* * * * *
    (e) You must submit a Notification of Compliance Status in
accordance with Sec.  63.10031(f)(4) or (h), as applicable, containing
the results of the initial compliance demonstration, as specified in
Sec.  63.10030(e).
* * * * *
    (g) * * *
    (3) You must report the emissions data recorded during startup and

shutdown. If you are relying on paragraph (2) of the definition of
``startup'' in Sec.  63.10042, then for startup and shutdown incidents
that occur on or prior to December 31, 2023, you must also report the
applicable supplementary information in Sec.  63.10031(c)(5) in the
semiannual compliance report. For startup and shutdown incidents that
occur on or after January 1, 2024, you must provide the applicable
information in Sec. Sec.  63.10031(c)(5)(ii) and 63.10020(e) quarterly,
in PDF files, in accordance with Sec.  63.10031(i).
* * * * *

Sec.  63.10020  [Amended]

0
 7. In Sec.  63.10020, paragraph (b) is amended by removing the words
``(see Sec.  63.8(c)(7) of this part)''.
0
 8. Section 63.10021 is amended by:
0
a. Revising paragraphs (e)(9) and (f);
0
b. Removing and reserving paragraph (h)(3); and
0
c. Revising paragraph (i).
    The revisions read as follows:

Sec.  63.10021  How do I demonstrate continuous compliance with the
emission limitations, operating limits, and work practice standards?

* * * * *
    (e) * * *
    (9) Prior to January 1, 2024, report the tune-up date
electronically, in a PDF file, in your semiannual compliance report, as
specified in Sec.  63.10031(f)(4) and (6) and, if requested by the
Administrator, in hard copy, as specified in Sec.  63.10031(f)(5). On
and after January 1, 2024, report the tune-up date electronically in
your quarterly compliance report, in accordance with Sec.  63.10031(g)
and section 10.2 of appendix E to this subpart. The tune-up report date
is the date when tune-up requirements in paragraphs (e)(6) and (7) of
this section are completed.
    (f) You must submit the applicable reports and notifications
required under Sec.  63.10031(a) through (k) to the Administrator
electronically, using EPA's Emissions Collection and Monitoring Plan
System (ECMPS) Client Tool. If the final date of any time period (or
any deadline) for any of these submissions falls on a weekend or a
Federal holiday, the time period shall be extended to the next business
day. Moreover, if the EPA Host System supporting the ECMPS Client Tool
is offline and unavailable for submission of reports for any part of a
day when a report would otherwise be due, the deadline for reporting is
automatically extended until the first business day on which the system
becomes available following the outage. Use of the ECMPS Client Tool to
submit a report or notification required under this subpart satisfies
any requirement under subpart A of this part to submit that same report
or notification (or the information contained in it) to the appropriate
EPA Regional Office or State agency whose delegation request has been
approved.
* * * * *
    (i) If you are relying on paragraph (2) of the definition of
``startup'' in Sec.  63.10042, you must provide reports concerning
activities and periods of startup and shutdown that occur on or prior
to January 1, 2024, in accordance with Sec.  63.10031(c)(5), in your
semiannual compliance report. For startup and shutdown incidents that
occur on and after January 1, 2024, you must provide the applicable
information referenced in Sec. Sec.  63.10031(c)(5)(ii) and 63.10020(e)
quarterly, in PDF files, in accordance with Sec.  63.10031(i).
0
8. Section 63.10030 is amended by:
0
a. Revising the last sentence in paragraph (e) introductory text and
paragraph (e)(7) introductory text;
0
b. Removing and reserving paragraph (e)(7)(i);
0
c. Revising paragraphs (e)(7)(iii) introductory text and
(e)(7)(iii)(A)(3);
0
d. Adding in paragraph (e)(7)(iii)(B) the word ``must'' after the word
``You''; and
0
e. Adding in paragraph (e)(7)(iii)(C) the word ``must'' after the word
``you''.
    The revisions read as follows:

Sec.  63.10030  What notifications must I submit and when?

* * * * *
    (e) * * * The Notification of Compliance Status report must contain
all of the information specified in paragraphs (e)(1) through (8) of
this section that applies to your initial compliance strategy.
* * * * *
    (7) Except for requests to switch from one emission limit to
another, as provided in paragraph (e)(7)(iii) of this section, your
initial notification of compliance status shall also include the
following information:
* * * * *
    (iii) For each of your existing EGUs, identification of each
emissions limit specified in Table 2 to this subpart with which you
plan to comply initially. (Note: If, at some future date, you wish to
switch from the limit specified in your initial notification of
compliance status, you must follow the procedures and meet the
conditions of paragraphs (e)(7)(iii)(A) through (C) of this section.)
    (A) * * *
    (3) Your request includes performance stack test results or valid
CMS data, obtained within 45 days prior to the date of your submission,
demonstrating that each EGU or EGU emissions averaging group is in
compliance with both the mass per heat input limit and the mass per
gross output limit;
* * * * *
0
9. Section 63.10031 is amended by:
0
a. Revising paragraphs (a), (b) introductory text, (b)(1), (2), (4),
and (5), and (c) introductory text;
0
b. Removing paragraphs (c)(5)(iii), (iv), and (v);
0
c. Adding paragraph (c)(10);
0
d. Revising paragraphs (d), (e), (f) introductory text, and (f)(1) and
(2);
0
e. Removing and reserving paragraph (f)(3);
0
f. Revising paragraphs (f)(4), (f)(6) introductory text, (f)(6)(vii)
and (xi), and (g); and
0
g. Adding paragraphs (h) through (k).
    The revisions and additions read as follows:

Sec.  63.10031   What reports must I submit and when?

    (a) You must submit each report in this section that applies to
you.
    (1) If you are required to (or elect to) monitor Hg emissions
continuously, you must meet the electronic reporting requirements of
appendix A to this subpart.
    (2) If you elect to monitor HCl and/or HF emissions continuously,
you must meet the electronic reporting requirements of appendix B to
this subpart. Notwithstanding the requirement in this paragraph (a)(2),
if you opt to certify your HCl monitor according to Performance
Specification 18 in appendix B to part 60 of this chapter and to use
Procedure 6 in appendix F to part 60 of this chapter for on-going QA of
the monitor, then, on and prior to December 31, 2023, report only
hourly HCl emissions data and the results of daily calibration drift
tests and RATAs performed on or prior to that date; keep records of all
of the other required certification and QA tests and report them,
starting in 2024.
    (3) If you elect to monitor filterable PM emissions continuously,
you must meet the electronic reporting requirements of appendix C to
this subpart. Electronic reporting of hourly PM emissions data shall
begin with the later of: The first operating hour on or after January
1, 2024; or the first operating hour after completion of the initial PM
CEMS correlation test.
    (4) If you elect to demonstrate continuous compliance using a PM
CPMS, you must meet the electronic reporting requirements of appendix D
to this subpart. Electronic reporting of the hourly PM CPMS output
shall begin

with the later of: The first operating hour on or after January 1,
2024; or the first operating hour after completion of the initial
performance stack test that establishes the operating limit for the PM
CPMS.
    (5) If you elect to monitor SO2 emission rate
continuously as a surrogate for HCl, you must use the ECMPS Client Tool
to submit the following information to EPA (except where it is already
required to be reported or has been previously provided under the Acid
Rain Program or another emissions reduction program that requires the
use of part 75 of this chapter):
    (i) Monitoring plan information for the SO2 CEMS and for
any additional monitoring systems that are required to convert
SO2 concentrations to units of the emission standard, in
accordance with Sec. Sec.  75.62 and 75.64(a)(4) of this chapter;
    (ii) Certification, recertification, quality-assurance, and
diagnostic test results for the SO2 CEMS and for any
additional monitoring systems that are required to convert
SO2 concentrations to units of the emission standard, in
accordance with Sec.  75.64(a)(5) of this chapter; and
    (iii) Quarterly electronic emissions reports. You must submit an
electronic quarterly report within 30 days after the end of each
calendar quarter, starting with a report for the calendar quarter in
which the initial 30 boiler operating day performance test begins. Each
report must include the following information:
    (A) The applicable operating data specified in Sec.  75.57(b) of
this chapter;
    (B) An hourly data stream for the unadjusted SO2
concentration (in ppm, rounded to one decimal place), and separate
unadjusted hourly data streams for the other parameters needed to
convert the SO2 concentrations to units of the standard.
(Note: If a default moisture value is used in the emission rate
calculations, an hourly data stream is not required for moisture;
rather, the default value must be reported in the electronic monitoring
plan.);
    (C) An hourly SO2 emission rate data stream, in units of
the standard (i.e., lb/MMBtu or lb/MWh, as applicable), calculated
according to Sec.  63.10007(e) and (f)(1), rounded to the same
precision as the emission standard (i.e., with one leading non-zero
digit and one decimal place), expressed in scientific notation. Use the
following rounding convention: If the digit immediately following the
first decimal place is 5 or greater, round the first decimal place
upward (increase it by one); if the digit immediately following the
first decimal place is 4 or less, leave the first decimal place
unchanged;