[Federal Register Volume 89, Number 31 (Wednesday, February 14, 2024)]
[Rules and Regulations]
[Pages 11198-11208]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2024-02634]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 60

[EPA-HQ-OAR-2002-0049; FRL-8150.1-03-OAR]


New Source Performance Standards Review for Steel Plants: 
Electric Arc Furnaces and Argon-Oxygen Decarburization Vessels; 
Corrections

AGENCY: Environmental Protection Agency (EPA).

ACTION: Interim final rule; request for comment.

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SUMMARY: The Environmental Protection Agency (EPA) is taking interim 
final action on corrections and clarifications to the new source 
performance standards (NSPS) for electric arc furnaces and argon-oxygen 
decarburization vessels in the steel industry. The corrections and 
clarifications are being made to address unintended and inadvertent 
errors in the recently finalized standards.

DATES: This interim final rule is effective on February 14, 2024. 
Comments on this rule must be received on or before March 15, 2024.

ADDRESSES: You may send comments, identified by Docket ID No. EPA-HQ-
OAR-2002-0049 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 protected]. Include Docket ID No. EPA-
HQ-OAR-2002-0049 in the subject line of the message.
     Fax: (202) 566-9744. Attention Docket ID No. EPA-HQ-OAR-
2002-0049.
     Mail: U.S. Environmental Protection Agency, EPA Docket 
Center, Docket ID No. EPA-HQ-OAR-2002-0049, Mail Code 28221T, 1200 
Pennsylvania Avenue NW, Washington, DC 20460.
     Hand/Courier Delivery: EPA Docket Center, WJC West 
Building, Room 3334, 1301 Constitution Avenue NW, Washington, DC 20004. 
The Docket Center's hours of operation are 8:30 a.m.-4:30 p.m., Monday-
Friday (except Federal Holidays).
    Comments received may be posted without change to https://www.regulations.gov, including any personal information provided. For 
detailed instructions on sending comments, see the ``Public 
Participation'' heading of the General Information section of this 
document under SUPPLEMENTARY INFORMATION.

FOR FURTHER INFORMATION CONTACT: Donna Lee Jones, Sector Policies and 
Programs Division (D243-02), 109 T.W. Alexander Drive, P.O. Box 12055, 
Office of Air Quality Planning and Standards, United States 
Environmental Protection Agency, Research Triangle Park, North Carolina 
27711; telephone number: (919) 541-5251; email address: 
[email protected].
    Preamble acronyms and abbreviations. Throughout this document the 
use of ``we,'' ``us,'' or ``our'' is intended to refer to the EPA. We 
use multiple acronyms and terms in this preamble. While this list may 
not be exhaustive, to ease the reading of this preamble and for 
reference purposes, the EPA defines the following terms and acronyms 
here:

AOD argon-oxygen decarburization
APA Administrative Procedure Act
BLDS bag leak detection system
CAA Clean Air Act
CBI confidential business information
CFR Code of Federal Regulations
CRA Congressional Review Act
DCOT during the digital camera opacity technique
DEC direct shell evacuation control
EAF electric arc furnace
EPA Environmental Protection Agency
FR Federal Register
FTP File Transfer Protocol
NAICS North American Industry Classification System
NSPS new source performance standards
NTTAA National Technology Transfer and Advancement Act
OMB Office of Management and Budget
PM particulate matter
PRA Paperwork Reduction Act
RFA Regulatory Flexibility Act
UMRA Unfunded Mandates Reform Act of 1995
U.S. United States of America
U.S.C. United States Code

    Organization of this document. The information in this preamble is 
organized as follows:

I. General Information
    A. Public Participation
    B. Potentially Affected Entities
    C. Statutory Authority
    D. Judicial Review and Administrative Review
II. Regulatory Revisions
    A. Background and Summary
    B. Specific Regulatory Revisions
III. Rulemaking Procedures
IV. Request for Comment
V. Statutory and Executive Order Reviews
    A. Executive Order 12866: Regulatory Planning and Review, as 
Amended by Executive Order 14094: Modernizing Regulatory Review
    B. Paperwork Reduction Act (PRA)
    C. Regulatory Flexibility Act (RFA)
    D. Unfunded Mandates Reform Act of 1995 (UMRA)
    E. Executive Order 13132: Federalism
    F. Executive Order 13175: Consultation and Coordination With 
Indian Tribal Governments
    G. Executive Order 13045: Protection of Children From 
Environmental Health Risks and Safety Risks
    H. Executive Order 13211: Actions Concerning Regulations That 
Significantly Affect Energy Supply, Distribution, or Use
    I. National Technology Transfer and Advancement Act (NTTAA) and 
1 CFR Part 51
    J. Executive Order 12898: Federal Actions To Address 
Environmental Justice in Minority Populations and Low-Income 
Populations and Executive Order 14096: Revitalizing our Nation's 
Commitment to Environmental Justice for All
    K. Congressional Review Act (CRA)

[[Page 11199]]


SUPPLEMENTARY INFORMATION: 

I. General Information

A. Public Participation

    Submit your written comments, identified by Docket ID No. EPA-HQ-
OAR-2002-0049, at https://www.regulations.gov (our preferred method), 
or by the other methods identified in the ADDRESSES section. Once 
submitted, comments cannot be edited or removed from the docket. The 
EPA may publish any comment received to its public docket. Do not 
submit to the EPA's docket at https://www.regulations.gov any 
information you consider to be Confidential Business Information (CBI) 
or other information whose disclosure is restricted by statute. This 
type of information should be submitted as discussed in the Submitting 
CBI section of this document. 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). Please visit https://www.epa.gov/dockets/commenting-epa-dockets for additional submission 
methods; the full EPA public comment policy; information about CBI or 
multimedia submissions; and general guidance on making effective 
comments.
    Submitting CBI. Do not submit information containing CBI to the EPA 
through https://www.regulations.gov. 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, note the docket ID, 
mark the outside of the digital storage media as CBI, and 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 the Public Participation section of this document. 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 and note the docket ID. 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.
    Our preferred method to receive CBI is for it to be transmitted 
electronically using email attachments, File Transfer Protocol (FTP), 
or other online file sharing services (e.g., Dropbox, OneDrive, Google 
Drive). Electronic submissions must be transmitted directly to the 
OAQPS CBI Office at the email address [email protected], and as 
described above, should include clear CBI markings and note the docket 
ID. If assistance is needed with submitting large electronic files that 
exceed the file size limit for email attachments, and if you do not 
have your own file sharing service, please email [email protected] to 
request a file transfer link. If sending CBI information through the 
postal service, please send it to the following address: OAQPS Document 
Control Officer (C404-02), OAQPS, U.S. Environmental Protection Agency, 
109 T.W. Alexander Drive, P.O. Box 12055 RTP, North Carolina 27711, 
Attention Docket ID No. EPA-HQ-OAR-2002-0049. The mailed CBI material 
should be double wrapped and clearly marked. Any CBI markings should 
not show through the outer envelope.

B. Potentially Affected Entities

    The source category that is the subject of this interim final 
action is composed of steel manufacturing facilities that operate 
electric arc furnaces (EAF) and argon-oxygen decarburization (AOD) 
vessels regulated under CAA section 111 New Source Performance 
Standards (NSPS). The 2022 North American Industry Classification 
System (NAICS) code for the source category is 331110 for ``Iron and 
Steel Mills and Ferroalloy Manufacturing'' processes. The NAICS code 
serves as a guide for readers outlining the type of entities that this 
interim final action is likely to affect.
    There are approximately 88 EAF facilities in the United States of 
America (U.S.), with most (>95 percent) EAF facilities subject to one 
of the EAF NSPS that are described below.
    The information provided in this section on potentially affected 
entities is not intended to be exhaustive. If you have questions 
regarding the applicability of this action to a particular entity, 
consult the person listed in the FOR FURTHER INFORMATION CONTACT 
section.

C. Statutory Authority

    Statutory authority to issue the amendments finalized in this 
action is provided by the same Clean Air Act (CAA) provisions that 
provided authority to issue the regulations being amended: CAA section 
111(b)(1)(B) (requirement to review, and if appropriate, revise, NSPS 
standards at least every 8 years), and CAA section 301, 42 U.S.C. 7601 
(general rulemaking authority). Statutory authority for the rulemaking 
procedures followed in this action is provided by Administrative 
Procedure Act (APA) section 553, 5 U.S.C. 553.

D. Judicial Review and Administrative Review

    Under CAA section 307(b)(1), judicial review of this final action 
is available only by filing a petition for review in the United States 
Court of Appeals for the District of Columbia Circuit by April 15, 
2024. Under CAA section 307(b)(2), the requirements established by this 
final rule may not be challenged separately in any civil or criminal 
proceedings brought by the EPA to enforce the requirements.

II. Regulatory Revisions

A. Background and Summary

    In 1975, the EPA first promulgated the EAF NSPS (subpart AA) to 
regulate emissions of particulate matter (PM) from new, reconstructed 
or modified EAF that produce steel. These standards apply to sources 
that commenced construction, modification, or reconstruction after 
October 21, 1974, and on or before August 17, 1983. In 1984, the EPA 
promulgated an updated EAF NSPS as subpart AAa, which revised the 
standards for EAF and also addressed AOD units. These standards apply 
to sources that commenced construction, modification or reconstruction 
after August 17, 1983, and on or before May 16, 2022. On August 25, 
2023, the EPA promulgated amendments to the EAF NSPS (88 FR 58459), 
including a new NSPS subpart AAb that establishes standards applicable 
to units that are new, modified, or reconstructed after May 16, 2022, 
as well as certain amendments to NSPS subparts AA and AAa that are 
applicable to units that began construction or reconstruction by the 
earlier dates specified in those two subparts.
    Relevant to this action, the 2023 final rule included the 
following: (1) a new NSPS subpart AAb which maintained the requirement 
for facilities to meet a shop opacity of six percent during charging 
\1\--the same as is required

[[Page 11200]]

under subparts AA and AAa; and required opacity testing to be performed 
once a day during charging for 3 minutes using EPA Method 9 in appendix 
A to part 60 of this chapter, from the average of 12 consecutive 
observations recorded at 15-second intervals; (2) a provision under 
subparts AA, AAa, and AAb that permits EAF, AOD, or both facilities 
with direct shell evacuation control (DEC) that want to avoid the 
requirement to use a furnace static pressure monitoring device to, as 
an alternative, perform observations of shop opacity no less than once 
per week from the end of one EAF heat cycle to the end of the following 
heat cycle (a heat cycle means the period beginning when scrap is 
charged to an EAF shell and ending when the EAF tap is completed or 
beginning when molten steel is charged to an AOD vessel and ending when 
the AOD vessel tap is completed); and (3) a compliance date for 
provisions applicable to facilities subject to subpart AA or AAa of 
February 21, 2024. The standards and requirements under subpart AAb 
were effective immediately upon publication of the final rule on August 
25, 2023.
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    \1\ There are three stages of EAF operation, where one of the 
three stages is charging of raw materials (metal scrap) into the 
EAF. Charging typically occurs in periods of less than 1 minute to 
up to 3 minutes. Steel is produced in batches, where a single batch 
can last from 1 hour to 10 hours, where 5 hours is a typical batch 
time period. Charging, therefore, is a small subset of the time that 
an EAF is operating.
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    Following issuance of the final rule, the EPA was notified by 
industry representatives of several errors in the final regulatory text 
for subparts AA, AAa, and AAb. The American Iron and Steel Institute 
(``AISI''), the Steel Manufacturers Association (``SMA''), and the 
Specialty Steel Industry of North America (``SSINA'') (collectively, 
``the Steel Associations'') submitted letters on August 17 and 
September 29, 2023, detailing concerns with the final rule, including 
certain new requirements in the final regulatory text, and requested 
corrections. In addition, on October 24, 2023, the Steel Associations 
submitted a petition for reconsideration and a request for an 
administrative stay pursuant to CAA section 307(d)(7)(B), identifying, 
among other issues, concerns with new requirements in the final 
regulatory text.\2\
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    \2\ On the same day, the Steel Associations filed a petition for 
review of the 2023 final rule in the D.C. Circuit. Am. Iron & Steel 
Institute v. EPA, No. 23-1292. The litigation is presently in 
abeyance while the EPA undertakes this action.
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    This action addresses errors identified by the Steel Associations, 
which are described in the following paragraphs, as well as errors 
identified by the EPA. This action does not attempt to address all 
issues identified in the Steel Associations communications, as the EPA 
continues to review the other issues not directly addressed in this 
action. To the extent the EPA determines that additional action is 
appropriate to address these other issues, we will initiate a separate 
rulemaking action.
    In the 2023 final rule, the EPA inadvertently included a 
requirement under subparts AA, AAa and AAb for observations of shop 
opacity to be performed by a certified visible emission observer no 
less than once per week for all EAF facilities subject to subparts AA, 
AAa or AAb, starting at the end of one EAF heat cycle and stopping at 
the end of the following heat cycle. The EPA never proposed nor 
intended to include such a requirement in the final rule. Because this 
requirement had not been included in the 2022 EAF NSPS proposed rule 
(87 FR 29710), the public did not have an opportunity to comment on 
this requirement, and the effects of the requirement were not included 
in the EPA's cost estimates or economic impact analysis for the 2023 
final rule (88 FR 58459).
    In addition, after the 2023 final rule was promulgated, the EPA 
discovered that the charging period associated with the finalized 
opacity testing requirement in NSPS subpart AAb, despite being the 
shortest operational period for an EAF, AOD or both, could be broken up 
into multiple discrete time periods at some EAF, AOD, or both and that 
the opacity plume for charging sometimes lasts after charging has 
stopped. Therefore, testing opacity ``during charging'' for a 
continuous 3-minute period, as the final EAF NSPS rule required, would 
not be possible in the case of multiple discrete charges or if the 
charging plume continues to be observable after charging of materials 
ceases.
    We also discovered a typographical error in the standards section 
of subpart AAb for measurement of shop opacity, where charging was 
mentioned twice instead of once and with two different sets of 
requirements. The duplicative references to ``charging'' would require 
testing both for 3 minutes and 6 minutes, and require no testing for 
tapping. This was inconsistent with other provisions of the rule that 
accurately described the testing requirements and with the EPA's 
clearly stated intent in the preamble that the 6-minute opacity testing 
was intended for tapping and the 3-minute testing was intended for 
charging. (88 FR 58459).
    Additional errors we are addressing in this action include: (1) 
correcting in 40 CFR 60.273(d)(2), 60.273a(d)(2), and 60.273b(d)(2) the 
omitted timing of the requirement to conduct shop opacity monitoring 
when more than one EAF are located in a shop; and (2) correcting in 40 
CFR 60.273(c), 60.273a(c), and 60.273b(e) the erroneous requirement 
included in the final rule that all fabric filters must have a 
continuous opacity monitoring system (COMS) or bag leak detection 
system (BLDS) by renumbering the regulatory text as 40 CFR 
60.273(c)(1)-(c)(3)/60.273a(c)(1)-(c)(3) and removing the phrase ``on 
all fabric filters'' in 40 CFR 60.273b(e); and (3) renumbering rule 
text in 40 CFR 60.274b(c)(1)-(c)(5) to clarify that the requirements in 
paragraphs (c)(1)-(c)(3) of Sec. Sec.  60.274, 60.274a, and 60.274b are 
a choice, and that (c)(4) and (c)(5) apply to any of the choices made 
in (c)(1)-(c)(3).
    We also discovered that several paragraphs under ``Monitoring of 
operations'' in subpart AA Sec.  60.274(b), (c), and (i), subpart AAa 
Sec.  60.274a(b), (c), and (h), and subpart AAb Sec.  60.274b(b), (c), 
and (h) do not reflect what we plainly stated in the preamble (88 FR 
58465, 58466, 58484), in response to comments, that we were not 
adopting the proposed rule provisions that would have required 
continuously monitoring of volumetric flow rate at each separately 
ducted hood and furnace static pressure, and instead were finalizing 
provisions that require recording these parameters as no greater than 
15-minute integrated block averages. Relatedly, the 2023 final 
regulatory text was ambiguous as to whether facilities needed to 
monitor 15-minute rolling averages or integrated block averages. Our 
stated intent in the preamble to the final rule was to require 15-
minute integrated block averages; therefore, in this action, in 
Sec. Sec.  60.274 and 60.274a, we are clarifying that volumetric flow 
rates and furnace static pressure are to be recorded as no greater than 
15-minute integrated block averages.
    Finally, we also discovered a phrase under ``Recordkeeping and 
reporting'' in subparts AA, AAa, and AAb under 40 CFR 60.276(a)/
60.276a(c)/60.276b(c) that was unintentionally and inadvertently 
deleted in the final regulations in regard to operation of fan motors 
for owners and operators that elect to install a furnace static 
pressure monitoring device. Specifically, the regulatory text 
inadvertently omitted a provision stating that ``operation of control 
system fan motor amperes at values exceeding 15 percent of 
the value established under 40 CFR 60.274(c)/60.274a(c)/60.274b(c)'' 
also constitutes unacceptable operation and maintenance of the affected 
facility. Therefore, we are restoring this phrase

[[Page 11201]]

in subparts AA, AAa, and AAb under 40 CFR 60.276(a)/60.276a(c)/
60.276b(c).
    The EPA is issuing this interim final rule to correct these errors 
included in the EAF NSPS 2023 final rule.

B. Specific Regulatory Revisions

    The regulatory revisions to 40 CFR part 60, subparts AA, AAa, and 
AAb that are being revised in this action include the following:
1. Corrections to 40 CFR Part 60, Subparts AA and AAa
    In this action, we are removing the inadvertently included 
requirement in 40 CFR 60.273(d)(2) and 60.273a(d)(2) ``Emission 
monitoring'' for lengthy, conflicting, and costly weekly opacity 
monitoring from the end of one EAF, AOD, or both heat cycles to the end 
of the following heat cycle, a time period that lasts from 1 to 10 
hours, with an estimated average of 5 hours. As written, the 
promulgated 2023 final rule erroneously required hours-long testing 
that would have significant cost impacts, which are estimated to be 
approximately $6 million per year. This requirement was not proposed 
and was inadvertently added into the final rule, without appropriate 
analysis and opportunity for public comment. Moreover, this requirement 
is not necessary to ensure compliance with the standard and would cause 
a significant unintended financial impact on the EAF, AOD, or both 
currently subject to NSPS subpart AA and AAa.
    We are also clarifying when to conduct the weekly shop opacity 
monitoring when there is more than one EAF located in a shop by adding 
``during the heat cycle as defined in 40 CFR 60.271,'' which was 
inadvertently omitted from the final rule. As written in the 2023 final 
rule 40 CFR 60.273(d)(2) and 60.273a(d)(2), the regulations are unclear 
as to when opacity monitoring should be completed. The clarification 
being finalized in this interim final current rule will require that 
once a week, facility shops with more than one EAF are to perform the 
required daily opacity monitoring when all EAF in the shop are 
operating. Following these corrections, subparts AA and AAa retain the 
requirement for daily opacity testing during melting and refining, 
tapping, and charging for time periods of 6, 6, and 3 minutes, 
respectively, as well as the requirement that facilities with more than 
one EAF in a shop test opacity once a week with all EAF in operation.
    In this action, we are also correcting errors in 40 CFR 60.273(c) 
and 60.273a(c) by removing the erroneous requirement included in the 
final rule that all fabric filters would need to install COMS or BLDS. 
As written, the promulgated 2023 final rule required a large capital 
investment for existing facilities with multi-stack fabric filters to 
install COMS or BLDS on each fabric filter. This erroneous requirement 
in the final rule is in direct conflict with both the preamble text (88 
FR 58465) and our finalized regulations in 40 CFR 60.273(e) and 
60.273a(e), which only require BLDS for single stack fabric filters 
that do not have COMS. Therefore, by adding in paragraph and 
subparagraph numbers (1)(i), (1)(ii), (2), and (3) in 40 CFR 60.273(c) 
and 60.273a(c) to make clear that multi-stack fabric filters are not 
required to install COMS or BLDS if observations of the opacity of the 
visible emission from the control device are performed by a certified 
visible emission observer, we will align Sec.  60.273(c) and Sec.  
60.273a(c) with Sec.  60.273(e) and Sec.  60.273a(e), respectively, and 
eliminate the requirement for existing facilities to install COMS or 
BLDS by February 21, 2024.
    We are clarifying 40 CFR 60.274(c)(1)-(5) and 60.274a(c)(1)-(5), 
which, as written in the final regulations, could be interpreted to 
allow the owner or operator to choose from one of five ways to monitor 
EAF operation when demonstrating compliance with the shop opacity 
standards in 40 CFR 60.272(a)(3) and 60.272a(a)(3) where a hood is used 
for capture, as described in paragraphs 40 CFR 60.274 and 60.274a in 
subparagraphs (c)(1), (c)(2), (c)(3), (c)(4), and (c)(5). This was an 
error. We are correcting the requirements, as intended, to clearly 
allow three choices of subparagraphs (c)(1), (c)(2), or (c)(3) to 
demonstrate compliance, but also to require a demonstration of 
compliance with both subparagraphs (c)(4) and (c)(5). These three 
choices of monitoring in subparagraphs (c)(1), (c)(2), and (c)(3) are 
choices between (c)(1), monitoring fan motor amperes at each damper 
position; (c)(2), monitoring volumetric flow rate through each hood; or 
(c)(3), monitoring volumetric flow rate at the control device inlet and 
with damper position. The last two subparagraphs of 40 CFR 60.274 and 
60.274a, specifically, (c)(4) and (c)(5), were intended to apply to any 
of the three monitoring choices in (c)(1), (c)(2), or (c)(3), where 
(c)(4) sets the time requirement for the monitoring as a rolling 
averaging period not to exceed 15 minutes, and (c)(5) describes how 
facilities can petition the Administrator to change any of the 
operating conditions that they had previously chosen among (c)(1), 
(c)(2), or (c)(3). Without this correction, the regulations do not 
clearly indicate how facilities are to appropriately monitor EAF, AOD, 
or both when demonstrating compliance with the shop opacity standard in 
40 CFR 60.272(a)(3) and 60.272a(a)(3) where a hood is used for capture. 
Therefore, as written in the 2023 final rule, facilities already 
subject to the applicable standards could inadvertently become 
noncompliant.
    We also are correcting subparts AA and AAa, ``Monitoring of 
operations'' in 40 CFR 60.274(b), (c), and (i) and 60.274a(b), (c), and 
(h) for the parameters of volumetric flow rate through each separately 
ducted hood and furnace static pressure by removing the requirements to 
record a rolling 15-minute average on a continuous basis. As stated in 
the final rule preamble (88 FR 58465, 58466), we intended to change 
this proposed provision in response to comments and replace it with the 
requirement to record as no greater than 15-minute integrated block 
averages. Without these corrections, the regulations would be 
inconsistent with our intended final action as described in the 2023 
final rule preamble, would not clearly indicate how facilities are to 
appropriately monitor EAF, AOD, or both, and facilities already subject 
to the applicable standards could inadvertently become noncompliant.
    Finally, we are correcting a requirement that was unintentionally 
and inadvertently deleted in subparts AA and AAa, ``Recordkeeping and 
reporting'' in 40 CFR 60.276(a)/60.276a(c)/60.276b(c), regarding the 
operation of fan motors for owners and operators that elect to install 
a furnace static pressure monitoring device under 40 CFR 60.274(f)/
60.274a(f)/60.274b(f). We are restoring the provision specifying that 
``operation of control system fan motor amperes at values exceeding 
15 percent of the value established under 40 CFR 60.274(c)/
60.274a(c)/60.274b(c)'' also constitutes unacceptable operation and 
maintenance of the affected facility in addition to operation at flow 
rates lower than those established under 40 CFR 60.274(c)/60.274a(c)/
60.274b(c). We never proposed to modify this provision and its deletion 
in the final rule was unintended. As written in the final regulations, 
facilities already subject to the applicable standards could 
inadvertently become noncompliant if we do not make this correction.
2. Corrections to Subpart AAb
    We are making the same correction to subpart AAb as described in in 
II.B.1 for subparts AA and AAa because the requirement for lengthy, 
conflicting, and

[[Page 11202]]

costly weekly opacity monitoring from the end of one EAF, AOD, or both 
heat cycles to the end of the following heat cycle'' in 40 CFR 
60.273b(d)(2) ``Emission monitoring'' was not proposed in 2022 (87 FR 
29710), was not intended to be included in the promulgated 2023 final 
rule (88 FR 58459), and is not necessary to ensure compliance with the 
standards. In addition, this provision was not included in the cost 
estimates for the final rule or economic impact analysis. The 
correction for subpart AAb in this action returns the requirement in 40 
CFR 60.273b(d)(2) to what had been proposed (87 FR 29710), where 
opacity testing was required to be performed at least once per day when 
the furnace is operating. This correction is consistent with the 
requirements in the standards section of the rule, at 40 CFR 
60.272b(a)(3), which were unchanged between the proposed rule (87 FR 
29710) and promulgated final rule (88 FR 58459).
    We are also clarifying, as we are in subparts AA and AAa, when to 
conduct the weekly shop opacity monitoring when there is more than one 
EAF located in a shop, by adding ``during the heat cycle as defined in 
40 CFR 60.271b.'' This clarification requires that once a week, 
facility shops with more than one EAF perform the required daily 
opacity monitoring when all EAFs are operating.
    Additionally in this action, we are correcting procedures for 
opacity testing of shop emissions under Method 9 in subpart AAb at 40 
CFR 60.271b ``Definitions,'' 40 CFR 60.272b(a)(3) ``Standard for 
particulate matter,'' and 40 CFR 60.273b(d)(3) ``Emission monitoring,'' 
to address the situation where charging periods at some EAF, AOD, or 
both may be broken into multiple, shorter periods of charging rather 
than one continuous charge, and for delayed plumes from charging. The 
final rule promulgated in 2023 (88 FR 58442) defined the charging 
testing period in subpart AAb as ``12 15-second continuous opacity 
observations'' (a total of 3 minutes) to accommodate the shorter 
periods of charging that are less than the 6 minutes required for 
melting and refining, and for tapping. However, as promulgated in the 
2023 final rule, this requirement may not always be technically 
feasible for a facility to meet. In this interim final rule, we are 
clarifying that the 3 minutes of opacity observation does not need to 
be continuous (although the observation periods should still total 3 
minutes), to accommodate EAF, AOD, or both that are charged in multiple 
short batches of less than a duration of 3 minutes each.
    In some instances, the opacity due to charging can continue to be 
observable after the charging activity has stopped, but before melting 
and refining begins. As provided in the 2023 final rule, the compliance 
testing requirements cannot be accurately completed at some facilities 
due to short charging periods and the requirement to only test opacity 
during charging. In this action, we are thus clarifying that the 
charging opacity observations can continue after the activity of 
charging ceases, up until melting and refining begins, which is 
necessary when opacity observations during charging have not yet 
reached 3 minutes in total and the charging opacity continues up until 
melting and refining begins.
    Therefore, this action corrects the charging opacity measurement 
regulatory text to remove ``continuous,'' and define the opacity 
measurement period as beginning when charging is first initiated and 
continuing until melting and refining begins, for a minimum of three 
minutes of total opacity readings. The result of this change is that 
the opacity test result for charging should be calculated from the 
average of the highest twelve 15-second opacity observations (total of 
3 minutes) during the charging period that is defined as beginning when 
charging is first initiated and continuing until melting and refining 
begins, to produce a 3-minute opacity average in an integrated sample, 
as permitted under section 2.5 of Method 9.
    We are correcting in this interim final rule a typographic error in 
40 CFR 60.272b(a)(3) ``Standard for particulate matter'' promulgated in 
the final rule in 2023 (88 FR 58459), where charging was required to be 
tested both without modification of the 6-minute observation time 
period as well as with modification to reduce the observation time 
period to 3 minutes. The former time period of 6 minutes should have 
been attributed to tapping and not charging, as is done in two other 
places in the 2023 final rule (i.e., in 40 CFR 60.271b ``Definitions'' 
and 40 CFR 60.273b(d)(3) ``Emission monitoring''). Therefore, we are 
correcting the first mention in 40 CFR 60.272b(a)(3) from ``charging'' 
to ``tapping''.
    Additionally in this action, we are making the same correction to 
subpart AAb, as described in in II.B.1, for subparts AA and AAa, by 
removing the requirement erroneously included in the final regulations 
in 40 CFR 60.273b(e) that all fabric filters need to have COMS or BLDS 
installed. By removing the phrase ``on all fabric filters'' to make 
clear that multi-stack fabric filters are not required to install COMS 
or BLDS if observations of the opacity of the visible emission from the 
control device are performed by a certified visible emission observer, 
we will align 40 CFR 60.273b(e) with 40 CFR 60.273b(c) and eliminate 
the need for all new, modified or reconstructed facilities to install 
COMS or BLDS upon startup. We are also making the same correction to 
subpart AAb, as described in II.B.1 for subparts AA and AAa, to allow a 
choice between 40 CFR 60.274b(c)(1), (c)(2), or (c)(3) to demonstrate 
compliance, but then also require a demonstration of compliance with 
both subparagraphs (c)(4) and (c)(5). Without this edit, the 
regulations do not clearly indicate how facilities are to appropriately 
monitor EAF, AOD or both when demonstrating compliance with the shop 
opacity standard in 40 CFR 60.272b(a)(3) where a hood is used for 
capture. Therefore, as written in our final rule, facilities could 
inadvertently become noncompliant.
    We are making the same correction to subpart AAb under ``Monitoring 
of operations'' in 40 CFR 60.274b(b), (c), and (h), as described in 
II.B.1 for subparts AA and AAa, for the parameters of volumetric flow 
rate through each separately ducted hood and furnace static pressure. 
We are removing the requirements to record ``rolling 15-minute averages 
on a continuous basis'' for the values for these parameters and 
replacing with the requirement to ``record as no greater than 15-minute 
integrated block averages.''
    Finally, we are making the same corrections to subpart AAb under 
``Recordkeeping and reporting requirements,'' as described in II.B.1 
for subparts AA and AAa, for a requirement that was unintentionally and 
inadvertently deleted in the final rule for subpart AAb under 40 CFR 
60.276b(c), in regard to operation of fan motor for owners and 
operators that elect to install a furnace static pressure monitoring 
device under 40 CFR 60.274b(f). We are restoring the provision 
specifying that ``operation of control system fan motor amperes at 
values exceeding 15 percent of the value established under 
40 CFR 60.274b(c)'' also constitutes unacceptable operation and 
maintenance of the affected facility in addition to operation at flow 
rates lower than those established under 40 CFR 60.274b(c).

III. Rulemaking Procedures

    As noted in section I.C. of this document, the EPA's authority for 
the rulemaking procedures followed in this

[[Page 11203]]

action is provided by APA section 553.\3\ In general, an agency issuing 
a rule under the procedures in APA section 553 must provide prior 
notice and an opportunity for public comment, but APA section 553(b)(B) 
includes an exemption from notice-and-comment requirements ``when the 
agency for good cause finds (and incorporates the finding and a brief 
statement of reasons, therefore, in the rule issued) that notice and 
public procedure thereon are impracticable, unnecessary, or contrary to 
the public interest.'' This action is being issued without prior notice 
or opportunity for public comment because the EPA finds that the APA 
``good cause'' exemption from notice-and-comment requirements applies 
here.
---------------------------------------------------------------------------

    \3\ Under CAA section 307(d)(1)(C), the EPA's promulgation or 
revision of any standard of performance under CAA section 111 would 
normally be subject to the rulemaking procedural requirements of CAA 
section 307(d), including notice-and-comment procedures, but CAA 
section 307(d) does not apply ``in the case of any rule or 
circumstance referred to in subparagraphs (A) or (B) of [APA section 
553(b)].'' CAA section 307(d)(1).
---------------------------------------------------------------------------

    Following notice-and-comment procedures is impracticable and 
unnecessary for this action. The costly, conflicting, and burdensome 
opacity emissions monitoring requirements inadvertently included in 
subparts AA, AAa, and AAb were not proposed and were never intended to 
become part of the regulatory text of the 2023 final rule. These 
opacity monitoring requirements, as described in section II. of this 
action, would add significant cost impacts to new and currently 
operating sources that were not considered or included in the 2023 
final rule because the EPA neither intended nor anticipated finalizing 
such a provision. These erroneous requirements are already in effect 
with respect to facilities subject to subpart AAb and will apply to 
facilities subject to NSPS subparts AA and AAa on February 21, 2024. 
Thus, it is critical to timely avoid this unintended and significant 
burden.
    Regarding the correction to subpart AAb for procedures for opacity 
testing of shop emissions under Method 9, the regulations as finalized 
are technically impossible for some facilities to meet due to opacity 
plumes that could be delayed after charging stops, but before melting 
and refining begins. Accordingly, a new facility that is constructed, 
modified, or reconstructed would be subject to compliance assurance 
provisions in subpart AAb with which the facility may not be able to 
comply. This would create an unreasonable situation where a facility 
could be considered to be in violation because it cannot comply with 
these compliance assurance requirements, even though it would be able 
to technically meet the applicable performance standard. Therefore, it 
is imperative that the EPA make this correction to ensure new, 
modified, and reconstructed are subject to opacity testing requirements 
that are achievable.
    Finally, this action is correcting several inadvertent errors in 
the regulatory text of the final rule. First, this action is removing a 
duplicative and contradictory reference in 40 CFR 60.272b(a)(3) to the 
charging requirement, which does not change the substance of the 
testing requirements. Second, this action is correcting regulatory text 
in subparts AA, AAa, and AAb that accidentally retained certain 
proposed language, contrary to the EPA's expressly stated intent in the 
final rule preamble. And third, the EPA is restoring provisions that 
were unintentionally deleted without prior notice or explanation and 
which should have been retained. This action corrects these oversights 
which, as described in section II., could cause some facilities to 
become inadvertently noncompliant with the standards and subject to 
potential enforcement action if not expeditiously corrected.
    This action is effective immediately upon publication. Section 
553(d) of the APA requires publication of the final rule to precede the 
effective date by at least 30 days unless, as relevant here, the rule 
relieves a restriction (40 CFR 553(d)(1)) or the agency finds good 
cause to make the rule effective sooner (40 CFR 553(d)(3)). Under APA 
section 553(d)(1), an exception applies to a rule that ``grants or 
recognizes an exemption or relieves a restriction.'' Because the 
corrections in this action relieve restrictions placed on facilities 
from the 2023 final rule (e.g., removing an unintended, burdensome and 
costly opacity monitoring requirement and relaxing unachievable testing 
requirements), the normal 30-day minimum period between this action's 
dates of publication and effectiveness is not required. Additionally, 
as explained throughout this action, because the corrections to the 
final rule relieve impracticable regulatory burdens and make 
ministerial clarifications, there is a secondary good cause basis for 
immediate effectiveness under APA section 553(d)(3). See Omnipoint 
Corp. v. Fed. Commc'n Comm'n, 78 F.3d 620, 630 (D.C. Cir. 1996) (in 
determining whether good cause exists to make a rule immediately 
effective, an agency should ``balance the necessity for immediate 
implementation against principles of fundamental fairness which require 
that all affected persons be afforded a reasonable amount of time to 
prepare for the effective date of its ruling''). Because the rule does 
not impose any new regulatory requirements, the regulated community 
does not need time to prepare for the rule to come into effect.

IV. Request for Comment

    As explained in section III. of this document, the EPA finds good 
cause to take this interim final action without prior notice or 
opportunity for public comment. However, the EPA is providing an 
opportunity for comment on the content of the amendments and, thus, 
requests comment on the corrections described in this rule. The EPA is 
not reopening for comment any provisions of the 2023 final rule other 
than the specific provisions that are expressly amended in this interim 
final rule.

V. Statutory and Executive Order Reviews

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

A. Executive Order 12866: Regulatory Planning and Review, as Amended by 
Executive Order 14094: Modernizing Regulatory Review

    This action is not a significant regulatory action as defined in 
Executive Order 12866, as amended by Executive Order 14094, and was 
therefore not subject to a requirement for Executive Order 12866 
review.

B. Paperwork Reduction Act (PRA)

    This action does not impose any new information collection burden 
under the PRA. The Office of Management and Budget (OMB) has previously 
approved the information collection activities that apply to the EAF 
facilities affected by this action and has assigned OMB control number 
2060-0038. This action does not change the information collection 
requirements.

C. 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. This 
action will not impose any requirements on small entities.

D. Unfunded Mandates Reform Act of 1995 (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

[[Page 11204]]

uniquely affect small governments. The action imposes no enforceable 
duty on any state, local or tribal governments or the private sector. 
This rule corrects unintended errors in previous rule.

E. 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.

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

    This action does not have Tribal implications as specified in 
Executive Order 13175. This rule will implement corrections and 
clarifications to rule text applicable directly to the regulated 
industry that needed clarification or that were erroneously included in 
final rule. Thus, Executive Order 13175 does not apply to this action.

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

    Executive Order 13045 directs Federal agencies to include an 
evaluation of the health and safety effects of the planned regulation 
on children in Federal health and safety standards and explain why the 
regulation is preferable to potentially effective and reasonably 
feasible alternatives. This action is not subject to Executive Order 
13045 because it is not a significant regulatory action under section 
3(f)(1) of Executive Order 12866, and because the EPA does not believe 
the environmental health or safety risks addressed by this action 
present a disproportionate risk to children. The EPA does not believe 
there are disproportionate risks to children because of this action 
since it will not result in any changes to the control of air 
pollutants.

H. 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.

I. National Technology Transfer and Advancement Act (NTTAA) and 1 CFR 
Part 51

    This action does not involve technical standards; therefore, the 
NTTAA does not apply.

J. Executive Order 12898: Federal Actions To Address Environmental 
Justice in Minority Populations and Low-Income Populations and 
Executive Order 14096: Revitalizing Our Nation's Commitment to 
Environmental Justice for All

    The EPA believes that this type of action does not concern human 
health or environmental conditions and, therefore, cannot be evaluated 
with respect to potentially disproportionate and adverse effects on 
communities with environmental justice concerns.

K. Congressional Review Act (CRA)

    This action is subject to the Congressional Review Act (CRA), 5 
U.S.C. 801-808, and the EPA will submit a rule report to each House of 
the Congress and to the Comptroller General of the United States. The 
CRA allows the issuing agency to make a rule effective sooner than 
otherwise provided by the CRA if the agency makes a good cause finding 
that notice and comment rulemaking procedures are impracticable, 
unnecessary, or contrary to the public interest (5 U.S.C. 808(2)). The 
EPA has made a good cause finding for this rule as discussed in section 
III. of this document, including the basis for that finding.

List of Subjects in 40 CFR Part 60

    Environmental protection, Administrative practice and procedures, 
Air pollution control, Incorporation by reference, Reporting and 
recordkeeping requirements.

Michael S. Regan,
Administrator.

    For the reasons set forth in the preamble, the EPA amends 40 CFR 
part 60 as follows:

PART 60--STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES

0
1. The authority citation for part 60 continues to read as follows:

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

Subpart AA--Standards of Performance for Steel Plants: Electric Arc 
Furnaces Constructed After October 21, 1974, and On or Before 
August 17, 1983

0
2. Amend Sec.  60.273 by revising paragraphs (c) and (d)(2) to read as 
follows:


Sec.  60.273  Emission monitoring.

* * * * *
    (c)(1) A continuous monitoring system for the measurement of the 
opacity of emissions discharged into the atmosphere from the control 
device(s) is not required:
    (i) On any modular, multistack, negative-pressure or positive-
pressure fabric filter if observations of the opacity of the visible 
emission from the control device are performed by a certified visible 
emission observer; or
    (ii) On any single-stack fabric filter if observations of the 
opacity of the visible emissions from the control device are performed 
by a certified visible emission observer and the owner installs and 
operates a bag leak detection system according to paragraph (e) of this 
section whenever the control device is being used to remove particulate 
matter from the EAF.
    (2) Visible emission observations shall be conducted at least once 
per day of the control device for at least three 6-minute periods when 
the furnace is operating in the melting and refining period. All 
visible emissions observations shall be conducted in accordance with 
EPA Method 9 of appendix A to this part, or, as an alternative, 
according to ASTM D7520-16 (incorporated by reference, see Sec.  
60.17), with the caveats described under Shop opacity in Sec.  60.271.
    (3) If visible emissions occur from more than one point, the 
opacity shall be recorded for any points where visible emissions are 
observed. Where it is possible to determine that a number of visible 
emission points relate to only one incident of the visible emission, 
only one set of three 6-minute observations will be required. In that 
case, EPA Method 9 observations must be made for the point of highest 
opacity that directly relates to the cause (or location) of visible 
emissions observed during a single incident. Records shall be 
maintained of any 6-minute average that is in excess of the emission 
limit specified in Sec.  60.272(a)(2).
    (d) * * *
    (2) No less than once per week, during a heat time as defined in 
Sec.  60.271, a melt shop with more than one EAF shall conduct these 
readings while all EAFs are in operation. All EAFs are not required to 
be on the same schedule for tapping.
* * * * *

0
3. Amend Sec.  60.274 by revising paragraphs (b)(1), (b)(3), (c), and 
(i)(9) to read as follows:


Sec.  60.274  Monitoring of operations.

* * * * *
    (b) * * *
    (1) Monitor and record once per shift the block 15-minute average 
furnace static pressure (if a DEC system is in

[[Page 11205]]

use, and a furnace static pressure gauge is installed according to 
paragraph (f) of this section) and either:
    (i) Install, calibrate, and maintain a monitoring device that 
continuously records the capture system fan motor amperes and damper 
position(s); or
    (ii) Monitor and record as no greater than 15-minute integrated 
block average basis the volumetric flow rate through each separately 
ducted hood; or
    (iii) Install, calibrate, and maintain a monitoring device that 
continuously records the volumetric flow rate at the control device 
inlet and record damper position(s).
* * * * *
    (3) Parameters monitored pursuant to this paragraph, excluding 
damper position, shall be recorded as integrated block averages not to 
exceed 15 minutes.
    (c)(1) When the owner or operator of an affected facility is 
required to demonstrate compliance with the standards under Sec.  
60.272(a)(3) and at any other time that the Administrator may require 
(under section 114 of the CAA, as amended), the owner or operator 
shall, during periods in which a hood is operated for the purpose of 
capturing emissions from the affected facility subject to paragraph (b) 
of this section, either:
    (i) Monitor and record the fan motor amperes at each damper 
position, and damper position consistent with paragraph (i)(5) of this 
section; or
    (ii) Monitor and record as no greater than 15-minute integrated 
block average basis the volumetric flow rate through each separately 
ducted hood; or
    (iii) Install, calibrate, and maintain a monitoring device that 
continuously records the volumetric flow rate at the control device 
inlet and monitor and record the damper position consistent with 
paragraph (i)(5) of this section.
    (2) Parameters monitored pursuant to this paragraph, excluding 
damper position, shall be recorded as integrated block averages not to 
exceed 15 minutes.
    (3) The owner or operator may petition the Administrator or 
delegated authority for reestablishment of these parameters whenever 
the owner or operator can demonstrate to the Administrator's or 
delegated authority's satisfaction that the EAF operating conditions 
upon which the parameters were previously established are no longer 
applicable. The values of the parameters as determined during the most 
recent demonstration of compliance shall be the appropriate operational 
range or control set point throughout each applicable period. Operation 
at values beyond the accepted operational range or control set point 
may be subject to the requirements of Sec.  60.276(a).
* * * * *
    (i) * * *
    (9) Parameters monitored pursuant to paragraphs (i)(6) through (8) 
of this section shall be recorded as integrated block averages not to 
exceed 15 minutes.

0
4. Amend Sec.  60.276 by revising paragraph (a) to read as follows:


Sec.  60.276  Recordkeeping and reporting requirements.

    (a) Continuous operation at a furnace static pressure that exceeds 
the operational range or control setting under Sec.  60.274(g), for 
owners and operators that elect to install a furnace static pressure 
monitoring device under Sec.  60.274(f) and either operation of control 
system motor amperes at values exceeding 15 percent of the 
value established under Sec.  60.274(c) or operation at flow rates 
lower than those established under Sec.  60.274(c) may be considered by 
the Administrator or delegated authority to be unacceptable operation 
and maintenance of the affected facility. Operation at such values 
shall be reported to the Administrator or delegated authority 
semiannually.
* * * * *

0
5. Amend the subpart AAa heading by revising it to read as follows:

Subpart AAa--Standards of Performance for Steel Plants: Electric 
Arc Furnaces and Argon-Oxygen Decarbonization Vessels Constructed 
After August 17, 1983, and On or Before May 16, 2022

* * * * *

0
6. Amend Sec.  60.273a by revising paragraphs (c) and (d)(2) to read as 
follows:


Sec.  60.273a  Emission monitoring.

* * * * *
    (c)(1) A continuous monitoring system for the measurement of the 
opacity of emissions discharged into the atmosphere from the control 
device(s) is not required:
    (i) On any modular, multistack, negative-pressure or positive-
pressure fabric filter if observations of the opacity of the visible 
emission from the control device are performed by a certified visible 
emission observer; or
    (ii) On any single-stack fabric filter if observations of the 
opacity of the visible emissions from the control device are performed 
by a certified visible emission observer and the owner installs and 
operates a bag leak detection system according to paragraph (e) of this 
section whenever the control device is being used to remove particulate 
matter from the EAF or AOD.
    (2) Visible emission observations shall be conducted at least once 
per day of the control device for at least three 6-minute periods when 
the furnace is operating in the melting and refining period. All 
visible emissions observations shall be conducted in accordance with 
EPA Method 9 of appendix A to this part, or, as an alternative, 
according to ASTM D7520-16 (incorporated by reference, see Sec.  
60.17), with the caveats described under Shop opacity in Sec.  60.271.
    (3) If visible emissions occur from more than one point, the 
opacity shall be recorded for any points where visible emissions are 
observed. Where it is possible to determine that a number of visible 
emission points relate to only one incident of the visible emission, 
only one set of three 6-minute observations will be required. In that 
case, EPA Method 9 observations must be made for the point of highest 
opacity that directly relates to the cause (or location) of visible 
emissions observed during a single incident. Records shall be 
maintained of any 6-minute average that is in excess of the emission 
limit specified in Sec.  60.272(a)(2).
    (d) * * *
    (2) No less than once per week, during the heat cycle as defined in 
Sec.  60.271a, melt shop with more than one EAF shall conduct these 
readings while all EAFs are in operation. All EAFs are not required to 
be on the same schedule for tapping.
* * * * *

0
7. Amend Sec.  60.274a by revising paragraphs (b)(1), (b)(3), (c), and 
(h)(9) to read as follows:


Sec.  60.274a  Monitoring of operations.

* * * * *
    (b) * * *
    (1) Monitor and record once per shift the block 15-minute average 
furnace static pressure (if a DEC system is in use, and a furnace 
static pressure gauge is installed according to paragraph (f) of this 
section) and either:
    (i) Install, calibrate, and maintain a monitoring device that 
continuously records the capture system fan motor amperes and damper 
position(s);
    (ii) Monitor and record as no greater than 15-minute integrated 
block average basis the volumetric flow rate through each separately 
ducted hood; or
    (iii) Install, calibrate, and maintain a monitoring device that 
continuously records the volumetric flow rate at the

[[Page 11206]]

control device inlet and record damper positions(s).
* * * * *
    (3) Parameters monitored pursuant to this paragraph, excluding 
damper position, shall be recorded as integrated block averages not to 
exceed 15 minutes.
    (c)(1) When the owner or operator of an affected facility is 
required to demonstrate compliance with the standards under Sec.  
60.272a(a)(3) and at any other time that the Administrator may require 
(under section 114 of the CAA, as amended), the owner or operator 
shall, during periods in which a hood is operated for the purpose of 
capturing emissions from the affected facility subject to paragraph (b) 
of this section, either:
    (i) Install, calibrate, and maintain a monitoring device that 
continuously records the fan motor amperes at each damper position, and 
damper position consistent with paragraph (h)(5) of this section; or
    (ii) Monitor and record as no greater than 15-minute integrated 
block average basis the volumetric flow rate through each separately 
ducted hood; or
    (iii) Install, calibrate, and maintain a monitoring device that 
continuously records the volumetric flow rate at the control device 
inlet and monitor and record the damper position consistent with 
paragraph (h)(5) of this section.
    (2) Parameters monitored pursuant to this paragraph, excluding 
damper position, shall be recorded as integrated block averages not to 
exceed 15 minutes.
    (3) The owner or operator may petition the Administrator or 
delegated authority for reestablishment of these parameters whenever 
the owner or operator can demonstrate to the Administrator's or 
delegated authority's satisfaction that the affected facility operating 
conditions upon which the parameters were previously established are no 
longer applicable. The values of the parameters as determined during 
the most recent demonstration of compliance shall be the appropriate 
operational range or control set point throughout each applicable 
period. Operation at values beyond the accepted operational range or 
control set point may be subject to the requirements of Sec.  
60.276a(c).
* * * * *
    (h) * * *
    (9) Parameters monitored pursuant to paragraphs (h)(6) through (8) 
of this section shall be recorded as integrated block averages not to 
exceed 15 minutes.

0
8. Amend Sec.  60.276a by revising paragraph (c) to read as follows:


Sec.  60.276a  Recordkeeping and reporting requirements.

* * * * *
    (c) Continuous operation at a furnace static pressure that exceeds 
the operational range or control setting under Sec.  60.274a(g), for 
owners and operators that elect to install a furnace static pressure 
monitoring device under Sec.  60.274a(f) and either operation of 
control system fan motor amperes at values exceeding 15 
percent of the value established under Sec.  60.274a(c) or operation at 
flow rates lower than those established under Sec.  60.274a(c) may be 
considered by the Administrator or delegated authority to be 
unacceptable operation and maintenance of the affected facility. 
Operation at such values shall be reported to the Administrator or 
delegated authority semiannually.
* * * * *

Subpart AAb--Standards of Performance for Steel Plants: Electric 
Arc Furnaces and Argon-Oxygen Decarbonization Vessels Constructed 
After May 16, 2022

0
9. Amend Sec.  60.271b by revising the definition ``Shop opacity'' to 
read as follows:


Sec.  60.271b  Definitions.

* * * * *
    Shop opacity means the arithmetic average of 24 observations of the 
opacity of any EAF or AOD emissions emanating from, and not within, the 
shop, during melting and refining, and during tapping, taken in 
accordance with Method 9 of appendix A of this part; and during 
charging, according to the procedures in section 2.5 of Method 9 in 
appendix A to part 60 of this chapter, with the following 
modifications: begin reading opacity when charging is first initiated 
and continue reading until melting and refining begins, or for a 
minimum of 3 minutes total. From the readings collected, take the 
average of the highest 12 15-second opacity observations (total of 3 
minutes) during this period to determine the 3-minute opacity average 
associated with charging. For the daily opacity observation during 
melting and refining, facilities may measure opacity by EPA Method 22 
of appendix A of this part, modified to require the recording of the 
aggregate duration of visible emissions at 15-second intervals. 
Alternatively, ASTM D7520-16 (incorporated by reference, see Sec.  
60.17), may be used with the following five conditions:
    (1) During the digital camera opacity technique (DCOT) 
certification procedure outlined in section 9.2 of ASTM D7520-16 
(incorporated by reference, see Sec.  60.17), the owner or operator or 
the DCOT vendor must present the plumes in front of various backgrounds 
of color and contrast representing conditions anticipated during field 
use such as blue sky, trees, and mixed backgrounds (clouds and/or a 
sparse tree stand);
    (2) The owner or operator must also have standard operating 
procedures in place including daily or other frequency quality checks 
to ensure the equipment is within manufacturing specifications as 
outlined in section 8.1 of ASTM D7520-16 (incorporated by reference, 
see Sec.  60.17);
    (3) The owner or operator must follow the recordkeeping procedures 
outlined in Sec.  60.7(f) for the DCOT certification, compliance 
report, data sheets, and all raw unaltered JPEGs used for opacity and 
certification determination;
    (4) The owner or operator or the DCOT vendor must have a minimum of 
four independent technology users apply the software to determine the 
visible opacity of the 300 certification plumes. For each set of 25 
plumes, the user may not exceed 15 percent opacity of any one reading 
and the average error must not exceed 7.5 percent opacity;
    (5) Use of this approved alternative does not provide or imply a 
certification or validation of any vendor's hardware or software. The 
onus to maintain and verify the certification and/or training of the 
DCOT camera, software, and operator in accordance with ASTM D7520-16 
(incorporated by reference, see Sec.  60.17) and these requirements is 
on the facility, DCOT operator, and DCOT vendor.
* * * * *

0
10. Amend Sec.  60.272b by revising paragraph (a)(3) to read as 
follows:


Sec.  60.272b  Standard for particulate matter.

    (a) * * *
    (3) Exit from a shop and, due solely to the operations of any 
affected EAF(s) or AOD vessel(s) during melting and refining exhibit 
greater than 0 percent opacity, and during tapping exhibit greater than 
6 percent opacity, as measured in accordance with Method 9 of appendix 
A of this part; and during charging, exhibit greater than 6 percent 
opacity, as measured according to the procedures in section 2.5 of 
Method 9 in appendix A to part 60 of this chapter, with the 
modification of this section of Method 9, as follows: begin reading 
opacity when charging is first initiated and continue reading until 
melting and refining begins, or for a minimum of 3 minutes total. From 
the readings

[[Page 11207]]

collected, take the average of the highest 12 15-second opacity 
observations (total of 3 minutes) during this period to determine the 
3-minute opacity average associated with charging. For the daily 
opacity observation during melting and refining, facilities may measure 
opacity by EPA Method 22 of appendix A of this part, modified to 
require the recording of the aggregate duration of visible emissions at 
15-second intervals. As an alternative, facilities may measure opacity 
according to ASTM D7520-16 (incorporated by reference, see Sec.  
60.17), with the caveats described under Shop opacity in Sec.  60.271 
or, for the daily opacity observations during melting and refining, 
exhibit 0 seconds of visible emissions as measured by EPA Method 22 of 
appendix A of this part, modified to require the recording of the 
aggregate duration of visible emissions at 15-second intervals. Shop 
opacity shall be recorded for any point(s) during melting and refining, 
during charging, and during tapping where visible emissions are 
observed. Where it is possible to determine that a number of visible 
emission sites relate to only one incident of visible emissions during 
melting and refining, during charging, or during tapping, only one 
observation of shop opacity or visible emissions will be required 
during melting and refining, during charging, or during tapping. In 
this case, the shop opacity or visible emissions observations must be 
made for the point of highest emissions during melting and refining, 
during charging, or during tapping that directly relates to the cause 
(or location) of visible emissions observed during a single incident.
* * * * *

0
11. Amend Sec.  60.273b by revising paragraphs (c), (d)(2), (d)(3), and 
(e) introductory text to read as follows:


Sec.  60.273b  Emission monitoring.

* * * * *
    (c)(1) A continuous monitoring system for the measurement of the 
opacity of emissions discharged into the atmosphere from the control 
device(s) is not required:
    (i) On any modular, multistack, negative-pressure or positive-
pressure fabric filter if observations of the opacity of the visible 
emission from the control device are performed by a certified visible 
emission observer; or
    (ii) On any single-stack fabric filter if observations of the 
opacity of the visible emissions from the control device are performed 
by a certified visible emission observer and the owner installs and 
operates a bag leak detection system according to paragraph (e) of this 
section whenever the control device is being used to remove particulate 
matter from the EAF or AOD.
    (2) Visible emission observations shall be conducted at least once 
per day of the control device for at least three 6-minute periods when 
the furnace is operating in the melting and refining period. All 
visible emissions observations shall be conducted in accordance with 
EPA Method 9 of appendix A to this part, or, as an alternative, 
according to ASTM D7520-16 (incorporated by reference, see Sec.  
60.17), with the caveats described under Shop opacity in Sec.  60.271.
    (3) If visible emissions occur from more than one point, the 
opacity shall be recorded for any points where visible emissions are 
observed. Where it is possible to determine that a number of visible 
emission points relate to only one incident of the visible emission, 
only one set of three 6-minute observations will be required. In that 
case, EPA Method 9 observations must be made for the point of highest 
opacity that directly relates to the cause (or location) of visible 
emissions observed during a single incident. Records shall be 
maintained of any 6-minute average that is in excess of the emission 
limit specified in Sec.  60.272b(a)(2).
    (d) * * *
    (2) No less than once per week, during the heat cycle as defined in 
Sec.  60.271b, a melt shop with more than one EAF shall conduct these 
readings while all EAFs are in operation. All EAFs are not required to 
be on the same schedule for tapping.
    (3) Shop opacity shall be determined as the arithmetic average of 
24 consecutive 15-second opacity observations of emissions from the 
shop taken in accordance with Method 9 during melting and refining and 
during tapping; and during charging determined according to the 
procedures in section 2.5 of Method 9 in appendix A to part 60 of this 
chapter, with the modification as follows: begin reading opacity when 
charging is first initiated and continue reading until melting and 
refining begins, or for a minimum of 3 minutes total. From the readings 
collected, take the average of the highest 12 15-second opacity 
observations (total of 3 minutes) during this period to determine the 
3-minute opacity average associated with charging. For the daily 
opacity observation during melting and refining, facilities may measure 
opacity by EPA Method 22 of appendix A of this part, modified to 
require the recording of the aggregate duration of visible emissions at 
15-second intervals. As an alternative, facilities may measure the 
opacity according to ASTM D7520-16 (incorporated by reference, see 
Sec.  60.17), with the caveats described under Shop opacity in Sec.  
60.271, or, during melting and refining, as the total duration of 
visible emissions measured according to EPA Method 22 over a 6-minute 
period, modified to require the recording of the aggregate duration of 
visible emissions at 15-second intervals. Shop opacity shall be 
recorded for any point(s) where visible emissions are observed. Where 
it is possible to determine that a number of visible emission points 
relate to only one incident of visible emissions, only one observation 
of shop opacity will be required. In this case, the shop opacity 
observations must be made for the point of highest opacity that 
directly relates to the cause (or location) of visible emissions 
observed during a single incident. Shop opacity shall be determined 
daily during melting and refining, during charging, and during tapping.
    (e) A bag leak detection system must be installed and operated on 
all single-stack fabric filters whenever the control device is being 
used to remove particulate matter from the EAF or AOD vessel if the 
owner or operator elects not to install and operate a continuous 
opacity monitoring system as provided for under paragraph (c) of this 
section. In addition, the owner or operator shall meet the visible 
emissions observation requirements in paragraph (c) of this section. 
The bag leak detection system must meet the specifications and 
requirements of paragraphs (e)(1) through (8) of this section.
* * * * *

0
12. Amend Sec.  60.274b by revising paragraphs (b), (c), and (h)(9) to 
read as follows:


Sec.  60.274b  Monitoring of operations.

* * * * *
    (b) Except as provided under paragraph (e) of this section, the 
owner or operator subject to the provisions of this subpart shall 
conduct the following monitoring of the capture system to demonstrate 
continuous compliance:
    (1) If a DEC system is in use, according to paragraph (f) of this 
section, monitor and record once per shift the block 15-minute average 
furnace static pressure and any one of (2) through (4) in this 
paragraph:
    (2) Install, calibrate, and maintain a monitoring device that 
continuously records the fan motor amperes at each damper position, and 
damper position consistent with paragraph (h)(5) of this section; or
    (3) Monitor and record as no greater than 15-minute integrated 
block average basis the volumetric air flow rate at each separately 
ducted hood; or

[[Page 11208]]

    (4) Install, calibrate, and maintain a monitoring device that 
continuously records the volumetric flow rate at the control device 
inlet and monitor and record the damper position consistent with 
paragraph (h)(5) of this section.
    (5) The furnace static pressure monitoring device(s) shall be 
installed in an EAF or DEC duct prior to combining with other ducts and 
prior to the introduction of ambient air, at a location that has no 
flow disturbance due to the junctions.
    (6) The volumetric flow monitoring device(s) may be installed in 
any appropriate location in the capture system such that reproducible 
flow rate monitoring will result. The flow rate monitoring device(s) 
shall have an accuracy of 10 percent over its normal 
operating range and shall be calibrated according to the manufacturer's 
instructions. The Administrator may require the owner or operator to 
demonstrate the accuracy of the monitoring device(s) relative to EPA 
Methods 1 and 2 of appendix A of this part.
    (7) Parameters monitored pursuant to this paragraph, excluding 
damper position, shall be recorded as integrated block averages not to 
exceed 15 minutes.
    (c)(1) When the owner or operator of an affected facility is 
required to demonstrate compliance with the standards under Sec.  
60.272b(a)(3) and at any other time that the Administrator may require 
(under section 114 of the CAA, as amended), the owner or operator 
shall, during all periods in which a hood is operated for the purpose 
of capturing emissions from the affected facility subject to paragraph 
(b) of this section, either:
    (i) Install, calibrate, and maintain a monitoring device that 
continuously records the fan motor amperes at each damper position, and 
damper position consistent with paragraph (h)(5) of this section;
    (ii) Monitor and record as no greater than 15-minute integrated 
block average basis the volumetric flow rate through each separately 
ducted hood; or
    (iii) Install, calibrate, and maintain a monitoring device that 
continuously records the volumetric flow rate at the control device 
inlet, and monitor and record the damper position consistent with 
paragraph (h)(5) of this section.
    (2) Parameters monitored pursuant to this paragraph, excluding 
damper position, shall be recorded as integrated block averages not to 
exceed 15 minutes.
    (3) The owner or operator may petition the Administrator or 
delegated authority for reestablishment of these parameters whenever 
the owner or operator can demonstrate to the Administrator's or 
delegated authority's satisfaction that the affected facility operating 
conditions upon which the parameters were previously established are no 
longer applicable. The values of the parameters as determined during 
the most recent demonstration of compliance shall be the appropriate 
operational range or control set point throughout each applicable 
period. Operation at values beyond the accepted operational range or 
control set point may be subject to the requirements of Sec.  
60.276b(c).
* * * * *
    (h) * * *
    (9) Parameters monitored pursuant to paragraphs (h)(6) through (8) 
of this section shall be recorded as integrated block averages not to 
exceed 15 minutes.

0
13. Amend Sec.  60.276b by revising paragraph (c) to read as follows:


Sec.  60.276b  Recordkeeping and reporting requirements.

* * * * *
    (c) Operation at a furnace static pressure that exceeds the 
operational range or control setting under Sec.  60.274b(g), for owners 
and operators that elect to install a furnace static pressure 
monitoring device under Sec.  60.274b(f) and either operation of 
control system fan motor amperes at values exceeding 15 
percent of the value established under Sec.  60.274b(c) or operation 
ranges or control settings outside of those established under Sec.  
60.274b(c) may be considered by the Administrator or delegated 
authority to be unacceptable operation and maintenance of the affected 
facility. Operation at such values shall be reported to the 
Administrator or delegated authority semiannually.
* * * * *
[FR Doc. 2024-02634 Filed 2-13-24; 8:45 am]
BILLING CODE 6560-50-P